Citation Nr: 21067540 Decision Date: 11/04/21 Archive Date: 11/04/21 DOCKET NO. 16-02 610 DATE: November 4, 2021 ISSUES 1. Entitlement to service connection for sigmoid colon cancer (for accrued purposes only). 2. Entitlement to service connection for bladder cancer (for accrued purposes only). 3. Entitlement to Dependency and Indemnity Compensation (DIC) under 38 U.S.C.§ 1318. ORDER Entitlement to service connection for sigmoid colon cancer, for accrued purposes, is denied. Entitlement to service connection for bladder cancer, for accrued purposes, is denied. Entitlement to Dependency and Indemnity Compensation (DIC) under 38 U.S.C.§ 1318 is denied. FINDINGS OF FACT 1. The Veteran did not participate in a radiation-risk activity in service. 2. The Veteran's sigmoid colon cancer is a radiogenic disease; however, the evidence does not demonstrate exposure to ionizing radiation. 3. The Veteran's bladder cancer is a radiogenic disease; however, the evidence does not demonstrate exposure to ionizing radiation. 4. The most probative evidence weighs against a finding that the Veteran's sigmoid colon cancer had its onset during active service, manifested within one year of service discharge, or is otherwise related to active service, to include radiation exposure therein. 5. The most probative evidence weighs against a finding that the Veteran's bladder cancer had its onset during active service, manifested within one year of service discharge, or is otherwise related to active service, to include radiation exposure therein. 6. The Veteran was not rated totally disabled for a continuous period of at least 10 years immediately preceding his death, nor was he rated totally disabled continuously since his release from active duty and for at least 5 years immediately preceding death, nor was he a former prisoner of war (POW). CONCLUSIONS OF LAW 1. The Veteran's sigmoid colon cancer was not incurred in active service, nor may it be presumed to have been so incurred. 38 U.S.C. §§ 1110, 1112, 1113, 1131, 1137, 5103, 5103A, 5107 (2012); 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.311 (2018). 2. The Veteran's bladder cancer was not incurred in active service, nor may it be presumed to have been so incurred. 38 U.S.C. §§ 1110, 1112, 1113, 1131, 1137, 5103, 5103A, 5107 (2012); 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.311 (2018). 3. The Veteran was not rated totally disabled for a continuous period of at least 10 years immediately preceding his death, nor was he rated totally disabled continuously since his release from active duty and for at least 5 years immediately preceding death, nor was he a former prisoner of war (POW). 4. The criteria for entitlement to Dependency and Indemnity Compensation (DIC) under 38 U.S.C. § 1318 have not been met. 38 U.S.C. § 1318; 38 C.F.R. § 3.22. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served in the United States Army from March 1970 to June 1990. He died in October 2017. The Appellant is his surviving spouse. This matter comes to the Board of Veterans' Appeals (Board) on appeal from July 2015 and May 2018 rating decisions by a Regional Office (RO) of the Department of Veterans Affairs (VA). In January 2019, the appellant testified at a Travel Board hearing before the undersigned Veterans' Law Judge (VLJ). The Veteran's claim of service connection for colon and bladder cancer was initially denied in July 2015, because the VA determined that there was no link with the condition in the military service. The Veteran filed a timely Notice of Disagreement (NOD) in August 2015. A Statement of the Case (SOC) was issued in December 2015 and the Veteran appealed the claim to the Board in January 2016. In November 2017, the Appellant submitted a request for substitution as claimant upon the death of the Veteran, which has been approved. The Appellant's entitlement to Dependent Indemnity Compensation (DIC) benefits claim was denied in May 2018. The Appellant filed a timely NOD in June 2018 and appealed the claim to the Board in July 2018. This matter was previously before the Board in October 2019, December 2020 and March 2021. In that October 2019 decision, the Board remanded the matter for further development. In the December 2020 decision, the Board remanded the matter for the purpose of obtaining a retrospective medical opinion from a physician with sufficient expertise, preferably an oncologist to opine on the etiology of this Veteran's sigmoid colon and bladder cancer. The matter was remanded again in March 2021 to obtain this retrospective medical opinion from a physician with sufficient expertise, preferably an oncologist. Sun an opinion was obtained in August 2021. The Board finds that there has been substantial compliance with its remand directives. See Stegall v. West, 11 Vet. App. 268, 271 (1998). This matter has now returned to the Board for further appellate action. The Board's discussion below will first address the Veteran's claim on a presumptive basis, as due to exposure to radiation, followed by a discussion of his claim on the basis of direct service connection for accrued purposes. The last part of this decision will discuss the Appellant's DIC claim. This appeal has been advanced on the Board's docket pursuant to 38 C.F.R. § 20.900(c), 38 U.S.C. § 7107(a)(2) (2012). Service Connection Entitlement to service connection for sigmoid colon cancer (for accrued purposes only). Entitlement to service connection for bladder cancer (for accrued purposes only). The Appellant claims that the Veteran developed sigmoid colon and bladder cancer as a result of exposure to radiation from repairing ground surveillance radar at various locations including Hawaii, Ft. Hood, TX and Germany. See August 6, 2016 Notice of Disagreement (NOD). The Board will discuss these disabilities together due to the common factual background. The Appellant has also asserted that the Veteran was exposed to ionizing radiation in the course of his job duties repairing ground surveillance radar at various locations. The Veteran military occupational specialty shows that he was an Electronics Maintenance Support Chief, 16 years, Recruiter/Retention, Noncommissioned Officer, 6 years. Military Personnel records show that the Veteran's primary duties included Radar Repairman, Senior Radar Repairman, Combat Area Surveillance Radar Repairman, Radar maintenance non commissioner officer. See DD-214; See also Military Personnel Records. Service Connection Service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by active service. 38 U.S.C. §§ 1110, 1131 (2012); 38 C.F.R. § 3.303(a) (2018). To establish a right to compensation for a present disability, a Veteran must show: (1) the existence of a present disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a causal relationship between the present disability and the disease or injury incurred or aggravated during service - the so-called "nexus" requirement. Holton v. Shinseki, 557 F.3d 1362, 1366 (Fed. Cir. 2009) (quoting Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004)). Service connection may be granted for disability resulting from disease or injury incurred in or aggravated by active military service. 38 C.F.R. § 3.303. Service connection may be granted for any disease initially diagnosed after service, when all the evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d) (2018). In addition, service connection for certain chronic diseases, including malignant tumors, may be established on a presumptive basis by showing that the condition manifested to a degree of 10 percent or more within one year from the date of separation from service. 38 U.S.C. §§ 1101, 1112, 1113, 1131, 1137 (2012); 38 C.F.R. §§ 3.307, 3.309(a) (2018); Fountain v. McDonald, 27 Vet. App. 258, 271-72 (2015). Although the disease need not be diagnosed within the presumptive period, it must be shown, by acceptable lay or medical evidence, that there were characteristic manifestations of the disease to the required degree during that time. 38 U.S.C. §§ 1101, 1112, 1113; 38 C.F.R. §§ 3.307, 3.309(a). Service connection for the cause of a Veteran's death is warranted if a service-connected disability either caused or contributed substantially or materially to the cause of the Veteran's death. 38 C.F.R. § 3.312(a). To establish service connection for the cause of a Veteran's death, competent evidence must link the fatal disease to a period of military service or an already service-connected disability. 38 U.S.C. § 1310; 38 C.F.R. §§ 3.303, 3.312; Ruiz v. Gober, 10 Vet. App. 352 (1997). In order to establish service connection for the cause of a Veteran's death, the evidence must show that a disability incurred in or aggravated by active service was the principal or contributory cause of death. A service-connected disability will be considered as the principal, or primary, cause of death when such disability, singly or jointly with some other condition, was the immediate or underlying cause of death or was etiologically related thereto. 38 C.F.R. § 3.312(b). In rendering a decision on appeal, the Board must analyze the credibility and probative value of the evidence, account for the evidence which it finds to be persuasive or unpersuasive and provide the reasons for its rejection of any material evidence favorable to the claimant. See Gabrielson v. Brown, 7 Vet. App. 36, 39-40 (1994); Gilbert v. Derwinski, 1 Vet. App. 49, 57 (1990). Radiation Service connection for a condition, which is claimed to be attributable to ionizing radiation exposure during service, may be established in one of three different ways. First, it may be presumptively service connected under 38 U.S.C. § 1112(c) and 38 C.F.R. § 3.309(d) if it is a disease specific to a "radiation-exposed veteran". Second, it may be service connected on a direct basis after specified development procedures are conducted under the special framework of 38 C.F.R. § 3.311 if the claimed entity is a "radiogenic disease." Third, even if it is not a listed disease under 38 C.F.R. § 3.309 or a radiogenic disease under 38 C.F.R. § 3.311, direct service connection can be established by showing that the disease was incurred during or aggravated by service, including presumptive service connection for chronic disease. See Combee v. Brown, 34 F.3d 1039, 1043 (Fed. Cir. 1994); Ramey v. Brown, 9 Vet. App. 40, 44 (1996), aff'd sub nom. Ramey v. Gober, 120 F.3d 1239 (Fed. Cir 1997); Hardin v. Brown, 11 Vet. App. 74, 77 (1998). The initial inquiry must focus on whether the Veteran is actually claiming exposure to "ionizing" radiation. (Emphasis added.) The U.S. Court of Appeals for Veterans Claims (CAVC) has taken judicial notice that radar equipment emits microwave-type non-ionizing radiation which is not subject to review under the ionizing radiation statute and regulations. Rucker v. Brown, 10 Vet. App. 67 (1997) citing The Microwave Problem, Scientific American, September 1986; Effects upon Health of Occupational Exposure to Microwave Radiation (RADAR), American Journal of Epidemiology, Vol. 112, 1980; and Biological Effects of Radiofrequency Radiation, United States Environmental Protection Agency, September 1984. Ionizing radiation (radiation sufficiently energetic to dislodge electrons from an atom) claims generally involve claimed exposure through participation in nuclear weapons testing, presence at certain sites following the detonation of a nuclear bomb or the production of nuclear material, service aboard nuclear submarines or even medical procedures involving radiation therapy and x-ray examinations. Ionizing radiation generally comes in the form of particulate (alpha, beta, neutrons) and electromagnetic (gamma and x-ray) rays. Non-ionizing radiation (radiation insufficiently energetic to dislodge electrons from an atom) claims involve claimed exposure to various forms of electromagnetic radiation that are often mistakenly alleged to come under the ionizing radiation statute and regulations. These claims may involve ultraviolet, visible light, infrared heat, microwaves and radio waves in devices such as cellular phones and telephone base stations, lasers, mercury vapor lamps, microwave ovens and towers, magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR), radar, radio and television broadcast antennas; satellite earth station antennas, transmitters and receivers; electrical power lines and transformers, etc. The Board notes that medical records indicate the Veteran was initially diagnosed with sigmoid colon cancer and bladder cancer in March 2009, and that the Veteran's death certificate lists stage 4 colorectal cancer as the cause of death. Cancer of the colon and bladder cancer are listed as "radiogenic" diseases in both 38 C.F.R. § 3.309(d) and 38 C.F.R. § 3.311. The Board concedes that the Veteran was diagnosed with and died from a radiogenic disease, namely sigmoid colon cancer. Id. If the Veteran has a radiation exposed disease listed in 38 C.F.R. § 3.309(d), the second step in this analysis is to determine whether the Veteran was involved in a "radiation-risk activity" as defined in 38 C.F.R. § 3.309(d)(3)(ii). There are six (6) types of radiation risk activity for purposes of 38 C.F.R. § 3.309. They are as follows: 1) onsite participation in a test involving the atmospheric detonation of a nuclear device; 2) participation in the occupation of Hiroshima or Nagasaki between August 6, 1945, and July 1, 1946; 3) POW in Japan (or service in Japan immediately after internment) with opportunity for exposure comparable to occupation forces in Hiroshima or Nagasaki; 4) service for at least 250 days before February 1, 1992 at gaseous diffusion plant in Paducah, Kentucky, or Portsmouth, Ohio, or at K25 area at Oak Ridge, Tennessee; 5) service before January 1, 1974, on Amchitka, Island, "if exposed to ionizing radiation" during duty related to Long Shot (1965), Milrow (1969) or Cannikin (1971) underground nuclear tests; or 6) service equivalent to employee of Department of Energy member of Special Exposure Cohort. In determining whether the Veteran participated in radiation-risk activities, VA has the duty to gather all relevant evidence from various sources of information. Earle v. Brown, 6 Vet. App. 558 (1994). Development While the Veteran has asserted exposure to radiation during service, specifically as due to his military occupational specialty, the Veteran's service records do not indicate that he participated in a radiation-risk activity as defined by 38 C.F.R. § 3.309(d)(3)(ii). The Board notes that the RO contacted the United States Army Dosimetry Center, which responded by letter in March 2018 that there were no records of exposure to ionizing radiation for this Veteran. See March 12, 2018 Correspondence (Army Dosimetry Center). Additionally, The RO contacted the United States Army Dosimetry Center in January 2020 and August 2020 which responded by letter that there were no records of exposure to ionizing radiation for the Veteran. See September 15, 2020 Correspondence (Army Dosimetry Center). In September 2020 the RO provided more detail about the Veteran's military occupational specialty, his military units, dates of service and deployment locations. In October 2020, the United States Army Dosimetry Center responded that they researched the files for records of exposure to ionizing radiation for this Veteran and that they were unable to locate any records for this Veteran. See October 22, 2020 Correspondence. (Receipt Date, November 3, 2020.) The RO undertook no further efforts to obtain a dose estimate or to refer the case to the Under Secretary for Benefits for an advisory medical opinion. The Board notes that although sigmoid colon cancer and bladder cancer is included in the list of diseases specific to radiation-exposed veterans, and for which service connection may be granted by presumption pursuant to 38 U.S.C. § 1112 (c) and 38 C.F.R. § 3.309 (d), and is also included as a radiogenic disease listed in 38 C.F.R. § 3.311, without evidence showing that the Veteran was exposed to ionizing radiation in service, neither of these provisions are applicable. Upon review of the record before the Board (i.e., Personnel service records, findings of the United States Dosimetry Center), the evidence does not demonstrate the Veteran's exposure to ionizing radiation in service. As such, the Board finds that service connection on a presumptive basis for sigmoid colon and bladder cancer is not warranted. However, the Federal Circuit has found that even if a Veteran is unable to establish presumptive service connection pursuant to 38 U.S.C. § 1112(c), 38 C.F.R. § 3.309(d), and 38 C.F.R. § 3.311, that the "Radiation Compensation Act does not, however, preclude or authorize the VA to preclude the veteran from proving actual direct causation if the veteran is able to do so." Combee v. Brown, 34 F.3d 1039, 1044 (Fed. Cir. 1999). Here, the Board observes that the Appellant and the Veteran, when he was alive, provided detailed statements regarding the scope and frequency of his exposure to radiation during the course of his service. The following is a snapshot of the scope and frequency of his exposure to non-ionizing radiation during the course of this Veteran's service. The Appellant testified at his January 2019 Board Hearing that the Veteran worked with ground surveillance radar equipment from March 1971 to 1982. See January 2019 Board Hearing testimony, pg.16; See also Military Personnel Records. The Veteran worked on four different types of equipment, including AN/PPS4/4A, AN/PPS5, TPS 21, and TPS 33. According to a December 2016 statement from the Veteran, the radars were built in the 1950s and were used during the Vietnam war. Although the Veteran worked on different radar equipment, he was responsible for repairing the AN/PPS4/4A and AN/PPS5 equipment on a daily basis. He stated that most of the installations required his team to wear full lead aprons and remove any jewelry repairing an AN/PPS4/41. The Veteran reported that one of the repairmen placed a raw chicken on a stick, then held it in front of the antenna and it started to cook. The Veteran stated that hazardous warning signs were placed at all installations, which accounted for the isolation of the radar section. He said that he and his team were constantly warned not to get in front of antenna while it was transmitting because it could cause sterilization. See October 31, 2016 Correspondence. The Veteran reported that in March 1972, he was stationed at HQCOA 124th MAINT 2AD in Ft. Hood, Texas 26 C 30 and worked on a trailer which was located away from the main electronic shop. He repaired the AN/PPS4/4A and AN/PPS5 radars. The Veteran stated that there were no lead aprons available at that installation in Ft. Hood. In 1974, the Veteran was stationed on COB, 163rd MAINT BN in Ft. Hood, TX, 26 C 30 and worked underground in a tunnel in an isolated area from the electronic shop. The Veteran reported that lead aprons were available and that he performed daily repairs on the AN/PPS4/4A and AN/PPS5 radars. In 1976, the Veteran was stationed with the 15th MAINT Co. in Germany, 26 C 30. He stated that he worked in isolated areas from the main electronics shop, lead aprons were available, and he was responsible for repairing the AN/PPS4/4A and AN/PPS5 radars. In 1979, the Veteran was stationed with the 4th SPT CNT in Ft. Hood, TX, 26 C 30. He reported that no lead aprons were made available, he worked in isolated areas from the main electronics shop and repaired the AN/PPS4/4A and AN/PPS5 radars on a daily basis. The Veteran stated that he worked at this location until 1982 when he was drafted to go on recruiting duty. See October 31, 2016 Correspondence; See also Military Personnel Records. The Board notes that the evidence of record has established that the Veteran has a current disability, sigmoid colon and bladder cancer. With respect to the second element of service connection, an in-service event, the Board also notes that Veteran's service treatment records are silent regarding and complaint, treatment or diagnosis related to sigmoid colon or bladder cancer. The Veteran was not diagnosed with these disabilities until March 2009. See February 15, 2013 Intestinal Surgery Disability Benefits Questionnaire; February 15, 2013 Prostate Cancer Disability Benefits Questionnaire (re: diagnosis, March 29, 2009 sigmoid colon cancer and bladder cancer respectively.) Given the above discussion with respect to the Veteran's duties as a radar repairman, the Board concedes the Veteran's reported in-service event of being exposed to electromagnetic waves (non-ionizing radiation) from radar equipment at multiple locations during his period of active-duty service. Hence, the second element of service connection on a direct service basis has been met. See Holton, 557 F.3d at 1366; 38 C.F.R. § 3.303(d). The key issue before the Board is whether there exists a "nexus" between the Veteran's sigmoid colon and bladder cancer and his claimed exposure to radiation during service. Nexus The Veteran submitted a November 2016 private nexus opinion from his oncologist regarding his service connections claims. His oncologist opined in this correspondence that based on the need and instruction to wear lead aprons, as well as being told that he risked sterility, [the Veteran] was exposed to ionizing radiation. The oncologist also stated that the Veteran reported that the equipment he worked on was at ground level and at pelvis level. His oncologist further opined that "if this indeed caused the radiation exposure, there is a probability that he was exposed to ionizing radiation and this may have caused or, at least contributed to his rectal carcinoma with a probability of > 50%." See November 2016 Correspondence (A.W.T., M.D). The Board observes, however, that the oncologist did not have the benefit of reviewing the Veteran's claims file and service record before rendering this nexus opinion. Nor could the physician factor in his analysis, the findings from the U.S. Army Dosimetry Center in March 2018, September 2020 and October 2020 that there were no records of exposure to ionizing radiation with regards to this Veteran during his active-duty military service. See March 12, 2018, September 15, 2020 and October22, 2020 Correspondence (Army Dosimetry Center). As such, the Board finds that this November 2016 private nexus opinion was based on the inaccurate factual premise that the Veteran was exposed to ionizing radiation during the course of his service. Further, the Board observes that this same oncologist acknowledges in earlier correspondence that he was not familiar with the particular equipment used by the Veteran during service, nor whether or not there was exposure to radioactive material. See May 12, 2015 Correspondence (A.W.T., M.D.). Because this November 2016 nexus opinion was based on an inaccurate factual premise, the Board assigns no probative weight private opinion. Retrospective Medical Opinions The Veteran has also been afforded retrospective medical opinions in January 2021, May 2021 and August 2021 to determine whether there is a nexus between the Veteran's sigmoid colon and bladder cancer and service. Each examiner rendered a negative nexus opinion to service. Because the January 2021 retrospective medical opinion was not rendered by a physician or oncologist, the matter was remanded again in March 2021 for further development. The May 2021 retrospective medical opinion was rendered by a physician. The May 2021 physician examiner noted review of the Veteran's entire claims folder, including the Veteran's personnel records, the March 2021 Board Remand, the January 22, 2021 VA Medical Opinion, private Medical Opinion, dated November 18, 2016 and Correspondence from the Appellant from the World Health Organization, dated March 1, 2021. See May 1, 2021 Medical Opinion, pgs. 2-3. The physician-examiner opined that the Veteran's claimed condition was less likely than not (less than 50 percent probability) incurred in or caused by the claimed in-service injury, event, or illness. With respect to sigmoid colon cancer, the examiner opined that there is no objective evidence in the medical records of a significant exposure to electromagnetic radiation. Furthermore, electromagnetic radiation is not an established primary etiology of the condition in the medical literature. With respect to the Veteran's bladder cancer, the examiner reported that there is no objective evidence in the medical records of a significant exposure to electromagnetic radiation. Furthermore, electromagnetic radiation is not an established primary etiology of the condition in the medical literature. Id. at 3. The Board notes that although this May 2021 Retrospective Medical Opinion was rendered by a physician, the Remand Directives instructed the RO to obtain a medical opinion from a physician with sufficient medical expertise, preferably an oncologist. Because this Retrospective Medical Opinion was not rendered by an oncologist, the Board does not rely on this opinion for purposes of adjudication. In August 2021, the Veteran was afforded an August 2021 retrospective medical opinion from an oncologist. See August 12, 2021 Medical Opinion. In the August 2021 Retrospective Medical Opinion, the examiner reported that there was no primary bladder cancer; it manifests a metastasis from colorectal cancer. See August 12, 2012 Retrospective Medical Opinion, pg. 1. The examiner noted review of the Veteran's entire claims file, including the Veteran's (a) Military Personnel records regarding his duty assignments in connection with his Radar Repair work, i.e., AN/PPS-5B Ground Surveillance Radar Set. See Military Personnel Records, Receipt Date August 7, 2015; (b) December 2016 Lay Correspondence regarding the Veteran's use of lead aprons during service; (c) a November 2016 Nexus Opinion from the Veteran's private physician; (d) March 2021 Correspondence from the Appellant from the World Health Organization, titled Radiation: Radar, November 2007; Occupational Safety and Health (OSHA) excerpts; (e) Lay correspondence, dated March 1, 2021 regarding the World Health Organization Report, receipt date, March 1, 2021. See August 2021 Medical Opinion, pg. 1. After review of the evidence of record, the oncologist-examiner rendered a negative nexus opinion to service. The examiner opined that the Veteran's claimed condition was less likely than not (less than 50 percent probability) incurred in or caused by the claimed in-service injury, event, or illness. The Board notes that the August 2021 examiner incorporated by reference in the rationale, the January 2021 examiner who reasoned that "based on the fact that the record of evidence from service show that the claimant would have been exposed to non-ionizing radiation, specifically Radiofrequency (RF) radiation which is used in many broadcast and communications applications. The fact that RF radiations biological effect is heating of body tissue with exposure to intense, direct amounts of non-ionizing radiation may result in damage to tissue due to heat, such as the described by the statement, "one of the repairmen placed a raw chicken on a stick, then held it in front of the antenna and it started to cook." The fact that Army Dosimeter Center letter dated October 22, 2020, stated, The U.S. Army Dosimetry Center researched the files for records of exposure to ionizing radiation for Mr. [REDACTED] and no records were found to support exposure to ionizing radiation. The fact that colorectal cancer is a common disease with approximately 147,950 new cases being diagnosed each year in the United States, of which 104,610 originate in the colon and the rest originate in the rectum. The fact that annually, approximately 51,020 Americans die of CRC, accounting for approximately 9 percent of all cancer deaths; in the United States. The fact that CRC ranks third in both incidence and cause of cancer death in both men and women. The fact that Dr A.T., M.D did not have access to the claim file and the Army Dosimeter center research that shows no evidence of exposure to ionizing radiation for Mr. [REDACTED] when the opinion was given. The fact that the medical opinion in the affirmative by A.W.T., M.D was based on an assumption that the claimant was exposed to ionizing radiation which was understandable given the reported history and no other objective evidence to the contrary. However, the current evidence of record does not support that assumption. Therefore, it is less likely than not that the Veteran's diagnosed sigmoid colon and bladder cancer (Colorectal Cancer with Mets to bladder based on tissue biopsy) is related to his active-duty service, or are otherwise related to any in-service disease, event, or injury, to include exposure to electromagnetic radiations (non-ionizing) exposure. References: UpToDate 2020: "Clinical presentation, diagnosis, and staging of colorectal cancer "UpToDate 2020 "Molecular genetics of colorectal cancer" https: //www.cdc.gov/nceh/radiation/nonionizingt_radiation.html." See August 12, 2021 Retrospective Medical Opinion, pg. 10. Importantly, the Board notes that the August 2021 oncologist-examiner carefully reviewed evidence provided by the Appellant. This evidence included (1) excerpts from a report from the World Health Organization (WHO) entitled Radiation; Radar dated November 2007; (2) excerpts from an Occupational Safety and Health Administration (OSHA); (3) the Veteran's December 7, 2016 statement in support of his claim, including a description of his radar repairmen duties, (4) the November 2016 opinion letter from the Veteran's private physician and (5) the Veteran's Death Certificate. With consideration of the Appellant's evidence from the World Health Organization, OSHA, the Veteran's radar repair duties, the November 2016 opinion letter from the Veteran's private oncologist and the Veteran's death certificate, the examiner rendered a negative nexus to service. Addressing excerpts from the World Health Organization, the examiner determined that the Appellant quoted excerpts from the primary source document selectively. The examiner reasoned that there is absolutely no support for her claim, no matter how it is perceived, reinforcing [by adoption-by-reference] the extensive analysis quoted [almost] in its entirety above. The examiner reasoned that this analysis serves to reinforce the statute that discounts any oncologic impact of radar. The examiner further reasoned that "in the absence of "eye cataracts and skin burns," it's difficult to surmise that the radar exposure caused any adverse medical impact; the rest of the WHO report is corroborative, including its summary [that hasn't been countered during subsequent years]: "At present, there is no substantive evidence that adverse health effects, including cancer, can occur in people exposed to Radio Frequency levels at or below the limits set by international standards. However, more research is needed to fill certain gap." See August 12, 2021 Medical Opinion, pgs. 1-12. The Board finds this retrospective medical opinion, read as a whole, probative for the following reasons: First, it was rendered by an oncologist-examiner who reviewed the Veteran's entire medical record, including but not limited to the Veteran's in-service treatment records, post-service treatment records and previous examinations of record. Second, the examiner considered the favorable evidence of record (Private Nexus Opinion, World Health Organization Report & OSHA report, excerpts), the Veteran's lay statements with respect to scope and frequency of his in-service exposure to radiation during his period of service, as well as arguments advanced by the Appellant. Third, the examiner provided a reasoned explanation for the conclusion reached. Stefl v. Nicholson, 21 Vet. App. 120, 124 (2007) (holding that a medical opinion must be supported by an analysis that the Board can consider and weigh against contrary opinions). Nieves-Rodriguez v. Peake, 22 Vet. App. 295, 302-04 (2008) (noting that the central issue in determining probative value of a medical opinion is whether the examiner was informed of the relevant facts). Any adequate medical opinion with regard to etiology should consist of a thorough review of the claims file and discussion of the relevant evidence (including the disability in question), a consideration of the lay contentions of the Veteran, and clear conclusions with a supporting rationale. Barr v. Nicholson, 21 Vet. App. 303, 311 (2007); Stefl v. Nicholson, 21 Vet. App. 120, 123 (2007); Nieves-Rodriguez v. Peake, 22 Vet. App. 295, 301 (2008). The Board errs by relying on an inadequate opinion. Ardison v. Brown, 6 Vet. App. 405, 407 (1994). However, a medical opinion does not have to be perfect; rather, it has to be adequate. For instance, there is no requirement that a medical examiner comment on every favorable piece of evidence in a claims file., 26 Vet. App. 97, 105 (2012); see Acevedo v. Shinseki, 25 Vet. App. 286 Monzingo v. Shinseki, 293 (2012) (noting that the law imposes no reasons-or-bases requirement on examiners). And where the opinion is lacking in detail, "the Board is permitted to draw inferences based on the overall report so long as the inference does not result in a medical determination." Acevedo, 25 Vet. App. at 294. Because the examiner considered the Veteran's lay statements with respect to the scope and frequency of his in-service exposure to electromagnetic radiation during the course of his service (including use of lead aprons), and addressed the Appellant's arguments with respect to in-service exposure to radiation in the context of the World Health Organization report, the Board find this examination report, taken as a whole, adequate for purposes of adjudication and persuasive as to the etiology of this Veteran's sigmoid colon and bladder cancer. The August 2021 opinion supports a finding that the Veteran's sigmoid colon cancer and bladder cancer did not have onset in service and is not otherwise related to service, to include exposure to radar therein. The opinion also supports a finding that the Veteran's sigmoid colon and bladder cancer, did not manifest to a compensable degree within one year of the Veteran's separation from active duty. The Board notes that the Veteran first received a diagnosis of sigmoid colon and bladder cancer in 2009, more than 15 years post-service. See February 15, 2013 Intestinal Surgery Disability Benefits Questionnaire; February 15, 2013 Prostate Cancer Disability Benefits Questionnaire (re: diagnosis, March 29, 2009 sigmoid colon and bladder cancer respectively.) To the extent that the Appellant contends that his sigmoid colon and bladder cancer is related to service, her contentions are not competent lay evidence. Although it is error to categorically reject a lay person as competent to provide an etiological opinion, not all such questions are subject to non-expert opinion. Davidson v. Shinseki, 581 F.3d 1313, 1316 (Fed. Cir. 2009). Whether a layperson is competent to provide a medical opinion depends on the facts of the particular case. "Lay evidence can be competent and sufficient to establish a diagnosis of a condition when (1) a layperson is competent to identify the medical condition, (2) the layperson is reporting a contemporaneous medical diagnosis, or (3) lay testimony describing symptoms at the time supports a later diagnosis by a medical professional." Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed. Cir. 2007). Lay witnesses are competent to report that which they have observed with their own senses. See Layno v. Brown, 6 Vet. App. 465, 469 (1994). But here, the specific etiology of sigmoid colon and bladder cancer, which is an internal medical process not capable of lay observation, is clearly distinguishable from, for example, ringing in the ears, a broken leg, or varicose veins. See Jandreau, 492 F.3d at 1377; Barr v. Nicholson, 21 Vet. App. 303, 310 (2007); Charles v. Principi, 16 Vet. App. 370, 374 (2002). Notwithstanding, the Appellant's compelling assertions are outweighed by the medical evidence of record, which is more probative as it is based upon the medical expertise of an oncologist and included a review of the Veteran's entire claims file, a review of the WHO and OSHA reports provided by the Appellant, with consideration of the Veteran's lay statements, including the Veteran's description of the scope and extent of his radar repairman duties during the course of his active-duty military service. The Board reiterates that because the November 2016 nexus opinion from the Veteran's private oncologist was based on an inaccurate factual premise (that the Veteran was exposed to ionizing radiation during service) the Board does not assign any probative value to this nexus opinion. The August 2021 oncologist examiner reasoned that there is absolutely no support for the Appellant's claim, and that in the absence of "eye cataracts and skin burns," it's difficult to surmise that the Veteran's radar exposure caused any adverse medical impact. After reviewing all of the lay and medical evidence of record, the examiner concluded that "at present, there is no substantive evidence that adverse health effects, including cancer, can occur in people exposed to Radio Frequency levels at or below the limits set by international standards. However, more research is needed to fill certain gap." See August 12, 2021 Retrospective Medical Opinion, pg. 12. As a final point, with consideration of all theories of entitlement, the Board notes that sigmoid colon cancer is not included on the enumerated list of conditions for which service connection may be presumed based upon exposure to herbicide agents. 38 C.F.R. § 3.309 (e). The Board is also cognizant that while bladder cancer was recently added to the list of conditions for which service connection may be presumed based upon such exposure, as referenced above in this decision, the Board finds that the most probative evidence of record documents that the Veteran's bladder cancer had metastasized from his primary cancer site in the colon. In the August 2021 Retrospective Medical Opinion, the examiner reported that there was no primary bladder cancer; it manifests a metastasis from colorectal cancer. See August 12, 2012 Retrospective Medical Opinion, pg. 1. Accordingly, as colon cancer is not entitled to presumptive service connection based upon exposure to herbicide agents, and the Veteran's bladder cancer was metastatic from his primary colon cancer, presumptive service connection for metastatic bladder cancer is also not warranted. 38 C.F.R. §§ 3.307(a)(6), 3.309(e); see also Darby v. Brown, 10 Vet. App. 243, 246 (1997) (holding that the presumption of service connection for lung cancer was rebutted by medical evidence showing that the stomach was the primary site of the cancer, which metastasized to the lungs); Ramey v. Brown, 9 Vet. App. 40, 44 (1996), aff'd sub nom. Ramey v. Gober, 120 F. 3d. 1239 (Fed. Cir. 1997); cert den., 522 U.S. 1151 (1998) (presumptive service connection refers to the primary cancer site and not a metastatic site). Returning to our direct service discussion and analysis: In summary, upon review of the lay and medical evidence of record, the Board finds that the most probative evidence weighs against a finding that the Veteran's sigmoid colon and bladder cancer had its onset during active service, manifested within one year of service discharge, or is otherwise related to active service, to include radiation exposure. Accordingly, service connection for accrued benefit purposes on a direct basis and on presumptive bases for the Veteran's claimed sigmoid colon and bladder cancer must be denied. In reaching this decision, the Board has considered the doctrine of reasonable doubt, however, as the preponderance of the evidence is against the Veteran's claim, the doctrine is not for application. Gilbert v. Derwinski, 1 Vet. App. 49 (1990). Entitlement to Dependency and Indemnity Compensation (DIC) benefits under 38 U.S.C. § 1318 is denied. The Appellant is claiming entitlement to DIC benefits under 38 U.S.C. § 1318. Under 38 U.S.C. § 1318, VA death benefits may be paid to a deceased veteran's surviving spouse in the same manner as if the veteran's death is service-connected, even though the veteran died of non-service-connected causes, if the veteran's death was not the result of his or her own willful misconduct and at the time of death, the veteran was receiving, or was entitled to receive, compensation for service-connected disability that was rated by VA as totally disabling for a continuous period of at least 10 years immediately preceding death; or was rated totally disabling continuously since the veteran's release from active duty and for a period of not less than five years immediately preceding death; or was rated by VA as totally disabling for a continuous period of not less than one year immediately preceding death if the veteran was a former POW who died after September 30, 1999. The total rating may be either schedular or based upon unemployability. 38 U.S.C. § 1318; see Rodriguez v. Peake, 511 F.3d 1147 (Fed. Cir. 2008). At the time of the Veteran's death, as noted above, service connection was in effect for tinnitus, rated at 10 percent disabling. He was not receiving total disability compensation, and was not entitled to a total disability rating within the language of 38 C.F.R. § 3.22 (b). It is undisputed that the Veteran was not a former POW and, therefore, the requirements of 38 U.S.C. § 1318 has not been satisfied. As such, entitlement to DIC under 38 U.S.C. § 1318 is not warranted. (Continued on next page.) ( In rendering this decision, the Board is cognizant of the Veteran's significant honorable service to our country and sympathizes with the loss that the appellant has sustained in the Veteran's untimely death. Unfortunately, the criteria for establishing DIC under 38 U.S.C. §§ 1318 have not been met, and the DIC is denied as a matter of law. Where the law is dispositive, the claim must be denied on the basis of absence of legal merit. Sabonis v. Brown, 6 Vet. App. 426, 430 (1994). Michael A. Pappas Veterans Law Judge Board of Veterans' Appeals Attorney for the Board C. Little, Associate Counsel The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.