Citation Nr: 1312783 Decision Date: 04/17/13 Archive Date: 05/02/13 DOCKET NO. 08-07 926 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in Phoenix, Arizona THE ISSUE Entitlement to service connection for the cause of the Veteran's death. REPRESENTATION Appellant represented by: Paralyzed Veterans of America, Inc. WITNESS AT HEARING ON APPEAL The appellant and her daughter ATTORNEY FOR THE BOARD Russell P. Veldenz, Counsel INTRODUCTION The Veteran served on active duty from December 1960 to November 1964 and from November 1967 to October 1976. The Veteran died in January 2007. The Appellant is his surviving spouse. This matter comes before the Board of Veterans' Appeals (Board) on appeal from a June 2007 rating decision by the Department of Veterans Affairs (VA) Regional Office in Phoenix, Arizona (RO). In December 2009, the Appellant appeared at a hearing before the undersigned Veterans Law Judge. A transcript of the hearing is in the record. In August 2010, and September 2011, the Board remanded the case to the RO for additional development. As the requested development has been completed, no further action is necessary to comply with the Board's remand directives. Stegall v. West, 11 Vet. App. 268, 271 (1998). Following the issuance of the supplemental statement of the case in August 2012, the Appellant submitted additional evidence in support of her claims and, through her service representative, waived the right to have the evidence initially considered by the RO. 38 C.F.R. § 20.1304(c). FINDINGS OF FACT 1. The death certificate establishes that the Veteran died in January 2007 at the age of 63 and the immediate cause of death was colon cancer. 2. At the time of the Veteran's death, he was service connected for mood disorder, diagnosed as major depressive disorder, which resulted from stress due to his service connected medical conditions, a chronic muscle strain of the back and degenerative instability with nerve root impingement, left lower extremity radiculopathy, right lower extremity radiculopathy, tinnitus, multiple healed left rib fractures, bilateral pneumothorax with scars, and bilateral hearing loss. 3. The medical evidence does not establish that the service-connected mood disorder, chronic muscle strain of the left back, left lower extremity radiculopathy, right lower extremity radiculopathy, tinnitus, multiple healed left rib fractures, bilateral pneumothorax with scars, and bilateral hearing loss caused or contributed substantially or materially to cause the Veteran's death 3. Colon cancer was not present during service; colon cancer was first manifested beyond the one- year presumptive period for cancer as a chronic disease; and colon cancer is unrelated to an injury, disease, or event during service, including exposure to Agent Orange or other herbicide exposure. CONCLUSION OF LAW A disability incurred in or aggravated by service, including Agent Orange or other herbicide exposure, did not cause or contribute to the cause of the Veteran's death. 38 U.S.C.A. §§ 1110, 1112, 1116, 1131, 1137, 1310, 5107(b) (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.312. (2012).) REASONS AND BASES FOR FINDINGS AND CONCLUSION The Veterans Claims Assistance Act of 2000 (VCAA) The VCAA, codified in part at 38 U.S.C.A. §§ 5103, 5103A, and implemented, in part, at 38 C.F.R § 3.159, amended VA's duties to notify and to assist a claimant in developing information and evidence necessary to substantiate a claim. Duty to Notify Under 38 U.S.C.A. § 5103(a) and 38 C.F.R. § 3.159(b), when VA receives a complete or substantially complete application for benefits, it will notify the claimant of the following: (1) any information and medical or lay evidence that is necessary to substantiate the claim, (2) what portion of the information and evidence VA will obtain, and (3) what portion of the information and evidence the claimant is to provide. Also, the VCAA notice requirements apply to all five elements of a service connection claim. The five elements are: 1) veteran status; 2) existence of a disability; 3) a connection between the Veteran's service and the disability; 4) degree of disability; and 5) effective date of the disability. Dingess v. Nicholson, 19 Vet. App. 473, 484-86 (2006). In a claim for dependency and indemnity compensation, including a claim of service connection for the cause of the veteran's death, the VCAA notice must include (1) a statement of the conditions, if any, for which a veteran was service-connected at the time of his death, (2) an explanation of the evidence and information required to substantiate the claim based on a previously service-connected condition, and (3) an explanation of the evidence and information required to substantiate the claim based on a condition not yet service connected. Hupp v. Nicholson, 21 Vet. App. 342, 352-53 (2007). The VCAA notice, as required by 38 U.S.C.A. § 5103(a), must be provided to a claimant before the initial unfavorable adjudication by the RO. Pelegrini v. Principi, 18 Vet. App. 112, 119 (2004). The RO provided pre- and post- adjudication VCAA notice by letter, dated in April 2007 and September 2010. The notice included the type of evidence needed to substantiate the underlying claims of service connection, namely, evidence of an injury or disease or event, causing an injury or disease, during service; evidence of current disability; and evidence of a relationship between the current disability and the injury or disease or event, causing an injury or disease, during service. The Veteran was notified that VA would obtain service treatment records, VA records, and records from other Federal agencies, and that he could submit other records not in the custody of a Federal agency, such as private medical records or with his authorization VA would obtain any non-Federal records on his behalf. The notice included the provisions for the effective date of a claim and for the degree of disability assignable. As for content of the VCAA notice, the documents complied with the specificity requirements of Quartuccio v. Principi, 16 Vet. App. 183, 186-87 (2002) (identifying evidence to substantiate a claim and the relative duties of VA and the claimant to obtain evidence); of Charles v. Principi, 16 Vet. App. 370, 374 (2002) (identifying the document that satisfies VCAA notice); of Pelegrini v. Principi, 18 Vet. App. 112, 119-120 (2004) (38 C.F.R. § 3.159 notice); of Dingess v. Nicholson, 19 Vet. App. 473, 484-86 (2006) (notice of the elements of the claim); Vazquez-Flores v. Peake, 580 F.3d 1270 (Fed. Cir. 2009) (evidence demonstrating a worsening or increase in severity of a disability and the effect that worsening has on employment); and of Hupp v. Nicholson, 21 Vet. App. 342, 352-53 (2007) (an explanation of the evidence and information required to substantiate the claim based on a previously service-connected condition and for a condition not yet service connected, and a statement of the conditions for which a veteran was service connected at the time of his death). Further VCAA notice is not required. To the extent that the VCAA notice came after the initial adjudication, the timing of the notice did not comply with the requirement that the notice must precede the adjudication. The timing error was cured by content-complying VCAA notice after which the claims were readjudicated as evidenced by the supplemental statements of the case, dated in August 2011 and August 2012. Mayfield v. Nicholson, 499 F.3d 1317, 1323 (Fed. Cir. 2007) (Timing error cured by adequate VCAA notice and subsequent readjudication without resorting to prejudicial error analysis.) Duty to Assist Under 38 U.S.C.A. § 5103A, VA must make reasonable efforts to assist the claimant in obtaining evidence necessary to substantiate the claim. The RO has obtained service treatment records, VA records, records from the Social Security Administration, letters from the Veteran's primary care provider regarding the cause of the Veteran's death, and provided a VA opinion regarding the cause of death in November 2010 with an addendum in December 2011. The report of the VA physician who provided the opinion, included a review of the Veteran's medical history, including his service treatment records, and provided the reasons and basis for his opinions. Therefore, the Board concludes that the VA opinion is adequate. 38 C.F.R. § 4.2; see Barr v. Nicholson, 21 Vet. App. 303, 312 (2007) (holding that when VA undertakes to provide a VA examination or obtain a VA opinion, it must ensure that the examination or opinion is adequate). As the Veteran has not identified any additional evidence pertinent to the claim and as there are no additional records to obtain, the Board concludes that no further assistance to the Veteran in developing the facts pertinent to the claims is required to comply with the duty to assist. Facts and Analysis When any Veteran dies from a service-connected disability, VA will pay dependency and indemnity compensation to such Veteran's surviving spouse. 38 U.S.C.A. § 1310. The death of a Veteran will be considered as having been due to a service-connected disability when the evidence establishes that such disability was either the principal or a contributory cause of death. A service-connected disability will be considered as the 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. A contributory cause of death is inherently one not related to the primary cause. 38 C.F.R. § 3.312. The standards for determining whether or not a disability is service connected are: Service connection may be granted for disability resulting from disease or injury incurred in or aggravated by service. 38 U.S.C.A. § 1110. Service connection means that the facts, shown by evidence, establish that a particular injury or disease resulting in disability was incurred coincident with service, or if preexisting such service, was aggravated by service. This may be accomplished by affirmatively showing inception or aggravation during service. 38 C.F.R. § 3.303(a). If a Veteran served 90 days or more on active duty, service incurrence will be presumed for certain chronic diseases, including malignant tumors, if the disease becomes manifest to a compensable degree within one year after service. 38 U.S.C.A. §§1112, 1137; 38 C.F.R. §§ 3.307, 3.309. Service connection may be established by either continuity of symptomatology after service under 38 C.F.R. § 3.303(b) or by initial diagnosis of the medical condition after service under 38 C.F.R. § 3.303(d). The Federal Circuit recently held that continuity of symptomatology under 3.303(b) applies only to chronic diseases listed in 3.309. Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2013). As noted, colon cancer, as a malignant tumor, is listed as a disease under § 3.309 as a chronic disease. For the showing of chronic disease in service there is required a combination of manifestations sufficient to identify the disease entity and sufficient observation to establish chronicity at the time, as distinguished from merely isolated findings or a diagnosis including the word "chronic." Continuity of symptomatology after discharge is required where the condition noted during service is not, in fact, shown to be chronic or where the diagnosis of chronicity may be legitimately questioned. 38 C.F.R. § 3.303(b). In cases where, as here, it is asserted that service connection should be granted due to Agent Orange exposure, a Veteran who, during active military, naval, or air service, served in the Republic of Vietnam during the Vietnam era (beginning in January 1962 and ending in May 1975) shall be presumed to have been exposed during such service to certain herbicide agents, including a herbicide commonly referred to as Agent Orange, unless there is affirmative evidence to establish that the Veteran was not exposed to any such agent during that service. 38 U.S.C.A. § 1116(a)(3); 38 C.F.R. §§ 3.307, 3.309. As the Veteran served in Vietnam, it is presumed that he was exposed to Agent Orange under 38 U.S.C.A. § 1116. If a Veteran was exposed to Agent Orange certain diseases will be presumed to have been incurred in service if manifest to a compensable degree within specified periods, even if there is no record of such disease during service, the diseases include certain cancers, but colon cancer is not one of the cancers listed. 38 U.S.C.A. § 1116(a)(2); 38 C.F.R. §§3.307(a)(6), 3.309(e). A metastasis of a cancer not associated with herbicide exposure is not entitled to the presumption of service connection due to Agent Orange exposure. See VAOPGCPREC 18-97 (May 2, 1997) (metastasis represents the progress of the nonservice-connected primary cancer, and is affirmative evidence that the secondary cancer was not the result of some other cause, such as herbicide exposure). Whenever VA's Secretary determines, on the basis of sound medical and scientific evidence, that a positive association exists between (A) the exposure of humans to an herbicide agent, and (B) the occurrence of a disease in humans, the Secretary shall prescribe regulations providing that a presumption of service connection is warranted for that disease. 38 U.S.C.A. § 1116(b)(1). As noted, colon cancer is not on the list of diseases subject to presumptive service connection due to exposure to Agent Orange. VA's Secretary has determined that a presumption of service connection based on exposure to certain herbicides, including Agent Orange, used in the Republic of Vietnam during the Vietnam era is not warranted for any condition for which the Secretary has not specifically determined a presumption of service connection is warranted. Notice, 59 Fed. Reg. 341 -346 (1994); 61 Fed. Reg. 41442 -41449 and 57586-57589 (1996); 67 Fed. Reg. 42600 - 42608 (2002); 68 Fed. Reg. 27630 -27641 (2003); 72 Fed. Reg. 32395 -32407 (2007) and Notice, 72 Fed. Reg. 32395 -32407 (2007); and 75 Fed. Reg. 32540 (2010). Notwithstanding the aforementioned provisions relating to presumptive service connection, which arose out of the Veteran's Dioxin and Radiation Exposure Compensation Standards Act, Pub. L. No. 98-542, § 5, 98 Stat. 2 ,725, 2,727-29 (1984), and the Agent Orange Act of 1991, Pub. L. No. 102-4, § 2, 105 Stat. 11 (1991), a claimant is not precluded from establishing service connection with proof of direct causation. Combee v. Brown, 34 F.3d 1039, 1042 (Fed. Cir. 1994). In order to establish service connection for the claimed disorder, there must be (1) medical evidence of a current disability; (2) medical, or in certain circumstances, lay evidence of in-service incurrence or aggravation of a disease or injury; and (3) medical evidence of a nexus between the claimed in-service disease or injury and the current disability. Hickson v. West, 12 Vet. App. 247, 253 (1999). The absence of any one element will result in the denial of service connection. Coburn v. Nicholson, 19 Vet. App. 427, 431 (2006). Secondary service connection may be granted for a disability that is proximately due to or the result of a service-connected disability. 38 C.F.R. § 3.310(a). Secondary service connection includes the concept of aggravation of a nonservice-connected disability by a service-connected disability. Allen v. Brown, 7 Vet. App. 439 (1995). Secondary service connection requires (1) evidence of a current disability; (2) evidence of a service connected disability; and (3) medical nexus evidence establishing a connection between the service connected disability and the current disability. Wallin v. West, 11 Vet. App. 509, 512 (1998). With respect to claims of service connection for a disability due to drug and alcohol abuse filed after October 31, 1990, the law prohibits an award of VA compensation for such disability, whether the claim is based on a theory of direct or secondary service connection. 38 U.S.C.A. §§ 105(a), 1110; 38 C.F.R. §§ 3.1(m), (n), 3.301, 3.310(a); VAOPGCPREC 11-96; VAOPGCPREC 2- 97; Libertine v. Brown, 9 Vet. App. 521, 523 (1996). Service connection may be granted for a disability caused by alcohol or drug abuse if there is clear medical evidence establishing that the alcohol or drug abuse is caused by a primary service-connected disability, and the alcohol or drug abuse disability is not due to willful wrongdoing. Allen v. Principi, 237 F. 3d. 1368, 1381 (Fed. Cir. 2001). Service connection may also be granted for any disease diagnosed after discharge, when all the evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d). VA must give due consideration to all pertinent lay and medical evidence. 38 U.S.C.A. § 1154(a). Competency is a legal concept in determining whether medical or lay evidence may be considered, in other words, whether the evidence is admissible as distinguished from weight and credibility, a factual determination going to the probative value of the evidence, that is, does the evidence tend to prove a fact, once the evidence has been admitted. Rucker v. Brown, 10 Vet. App. 67, 74 (1997). Competency is a question of fact, which is to be addressed by the Board. Jandreau, v. Nicholson, 492 F.3d 1372, 1377 (2007). When the evidence is admissible, the Board must then determine whether the evidence is credible. "Credible evidence" is that which is plausible or capable of being believed. See Caluza v. Brown, 7 Vet. App. 478, 511 (1995), aff'd per curiam, 78 F. 3d 604 (Fed. Cir. 1996) (the determination of credibility is a finding of fact to be made by the Board in the first instance). If the evidence is credible, the Board, as fact finder, must determine the probative value or weight of the admissible evidence, that is, does the evidence tend to prove a material fact. Washington v. Nicholson, 19 Vet. App. 362, 369 (2005). When there is an approximate balance of positive and negative evidence regarding any issue material to the determination of a matter, the Secretary shall give the benefit of the doubt to the Veteran. 38 U.S.C.A. § 5107(b). In this case, the Appellant asserts that the Veteran's death from colon cancer was the proximate result of exposure to herbicides (Agent Orange) during the Veteran's Vietnam service. His service personnel records confirm that he had in-country service for the purposes of establishing herbicide exposure. The service treatment records, including both his service in the United States Navy from December 1960 to November 1964 and the United States Air Force from November 1967 to October 1976 do not demonstrate any diagnosis or treatment for colon cancer nor are there any complaints, symptoms, signs, or treatment of a gastrointestinal nature that appear related to colon cancer. A long history of heavy alcohol use is documented in a June 1982 VA inpatient treatment record as having begun prior to the Veteran's first service separation, and shown in the VA treatment records to have continued to exist as recently as 2000. There are indications the Veteran started drinking when he was as young as thirteen to fifteen years old. Additionally, the Veteran had a long history of tobacco abuse; VA outpatient treatment records dated beginning in the 1980s reflect use of between one-half and three packs per day, to include a habit of two packs per day as late as March 2006. Again, the Veteran started smoking tobacco before his first period of service, starting when he was a teenager. In an April 1987 Agent Orange exposure examination in April 1987, there was no family history of cancer and physical examination of the abdomen and rectum was negative. In September 1991, radiological studies of the upper gastrointestinal area were normal. A CT scan of the abdomen and kidney was negative in March 1999. In February 2001, the Veteran sought treatment for painful hemorrhoids that were noted to be on the outside. In July 2003, an x-ray demonstrated a probable or early small bowel obstruction with low density areas or 3 small lesions in the liver. The Veteran subsequently underwent a laporatomy and removal of a circumferential adenocarcinoma of the ascending colon. The lesions on the liver were determined to be metastasis of the colon cancer. The Veteran was still smoking although he had stopped using alcohol a year earlier. The cancer was determined to be at stage IV. After surgery, he underwent chemotherapy. In July 2005, the Veteran underwent a colonoscopy and three polyps were removed. The pathology diagnosis for two polyps was tubular adenocarcinoma. The Third polyp was diagnosed as a hyperplastic polyp. In January 2006, a CT scan of the abdomen demonstrated multiple metastasis lesions in the lungs, liver, and the left adrenal gland. By March 2006, the Veteran's physician stated the Veteran had metastatic incurable colon cancer which failed surgery and chemotherapy. The Veteran was considered to be terminally ill. In April 2006, a VA examiner evaluating the Veteran's mental health disability noted that the Veteran was dying of cancer and also concluded that the Veteran's health substance abuse was an attempt to ameliorate symptoms of anxiety and depression. The Veteran died in January 2007. The death certificate indicated he was 63 years old and the primary and only cause of death listed was colon cancer. A VA medical professional, who treated the Veteran prior to his death for his fatal adenocarcinoma of the colon, has provided opinions linking the Veteran's death to Agent Orange exposure, specifically dioxin as a part of the chemical make-up of a herbicide. In March 2006, prior to his death, the Veteran's treating nurse practitioner wrote a letter in which she concluded that since dioxin (herbicide) is known to cause adenocarcinoma of the colon, it was her opinion that the Veteran's colon cancer and subsequent metastasis was probably a direct result of his exposure to dioxin. After the Veteran's death, a nearly identical statement was received by VA from the VA nurse practitioner in January 2010, then noting that the colon cancer was more likely than not a direct result of the Veteran's exposure to dioxin. The surviving spouse in her claim for benefits stated that the Veteran's physicians said the cancer was caused by the toxic chemicals he handled in Vietnam. The spouse also asserts that her husband developed colon cancer due to Agent Orange exposure in service. She also states that he had no medical disabilities from service from1960 to 1964 in the United States Navy and was in sound medical condition when he entered the United States Air Force. The Board notes that the spouse was not married to the Veteran during either period of service. A VA physician in November 2010 reviewed the VA claims folder and offered a medical opinion that the Veteran's exposure to herbicides in Vietnam did not cause or contribute substantially or materially to his death from colon cancer, given that medical literature did not support a relationship between colon cancer and agent orange or other herbicide exposure. Regarding the impact of the Veteran's alcohol and tobacco abuse, the VA physician stated that a review of medical literature suggested an association between alcohol/tobacco abuse; however, that association was described as weak, with many other risk factors being of greater significance, including age, family history, ethnicity, colorectal polyps, inflammatory bowel disease, personal history of other cancers, and dietary factors. In an addendum to his opinion dated in December 2011, the physician cited an article discussing the overview of the association between Agent Orange and various types of cancer published in 2003. Three articles were cited to support his conclusion that the association between colon cancer and/or alcohol and tobacco use was weak. In October 2011, the VA nurse practitioner who submitted the March 2006 and January 2010 letters submitted another letter regarding her opinion that the Veteran's colon cancer resulted from exposure to herbicides such as Agent Orange. The letter was also signed by a VA physician, but the nurse practitioner, J. G. Ahlemeyer, made it clear she authored the letter as well as the earlier letters and all physicians signed only because internal VA procedures required the addition of a signature by a VA physician. The physicians were not involved in the Veteran's treatment. In the October 2011 history, the nurse practitioner stated the Veteran, while stationed in Vietnam, loaded spray planes and helicopters with Tetrachlorodibenzo-p-dioxin, or TCDD-Agent Orange. He also served as part of an aircraft recovery team for aircraft downed in the jungles, a sniper, and a tunnel rat. Nurse practitioner Ahlemeyer relied upon eight articles from the medical literature, including a 2010 medical study that at least as likely as not there is a casual relationship exists between Agent Orange and colon cancer although the article apparently also concludes the evidence is not sufficient to definitively say that the casual relationship exists. She also cited other medical articles relating the development of adenocarcinoma of the colon many years after exposure to Agent Orange. The relationship between Agent Orange and other cancers that develop as a result of exposure were cited as well. As to the Veteran's use of alcohol and tobacco use, the letter opinion noted that such use may compound the effect of herbicide exposure. Thus, the nurse practitioner admitted alcohol and tobacco abuse contributed to the diagnosis of colon cancer, but Agent Orange exposure was the catalyst for the disease. The alcohol and tobacco were used by the Veteran as coping mechanisms for PTSD symptoms. As for other factors, there was no family history for colon cancer, and the Veteran, a Caucasian, did not have a history of inflammatory bowel disease. Service Connection Other than as due to Agent Orange Exposure As a preliminary matter, the Veteran was connected for the following disabilities during his life time: mood disorder, diagnosed as major depressive disorder, which resulted from stress due to his service connected medical conditions, a chronic muscle strain of the back and degenerative instability with nerve root impingement, left lower extremity radiculopathy, right lower extremity radiculopathy, tinnitus, multiple healed left rib fractures, bilateral pneumothorax with scars, and bilateral hearing loss. The Board understands the Appellant as not claiming any service-connected disability caused or contributed to the Veteran's death, nor is there any medical evidence in the file suggesting such a relationship. Therefore, the Veteran's death is not service connected on the basis that an already service-connected disability caused or contributed to the cause of the Veteran's death. 38 U.S.C.A. § 1310. The Veteran was not service connected for PTSD. The Board notes that the file contains a prior Board decision involving service connection for the death of another Veteran. To the extent that it is asserted by the Appellant that the facts are essentially similar and that the Board should adopt the same holding of granting service connection for the Veteran's death. The Board notes that previously issued Board decisions are binding only with regard to the specific case involved and the Appellant's case will be decided on the basis of the individual facts of the case in light of applicable procedure and substantive law. 38 C.F.R. § 20.1303. On the basis of the service treatment records, colon cancer was not affirmatively shown to have had onset during service and direct service connection under 38 U.S.C.A. § 1110 and 38 C.F.R. § 3.303(a) is not established. And as there is no competent evidence either contemporaneous with or after service that colon cancer was noted during service, that is, observed during service, the principles of service connection pertaining to chronicity and continuity of symptomatology under 38 C.F.R. § 3.303(b) do not apply. Savage v. Gober, 10 Vet. App. 488, 495-96 (1997). After service, the record shows that colon cancer was first diagnosed in July 2003 well beyond the one year presumptive period following separation from service in 1976 for colon cancer as a chronic disease under 38 U.S.C.A. § 1112 and 38 C.F.R. §§ 3.307, 3.309. Excluding exposure to Agent Orange, which is addressed separately, there is no competent evidence in the current record that colon cancer, first diagnosed after service in 2003, is otherwise related to an injury, disease, or event of service origin under 38 C.F.R. § 3.303(d). Exposure to Agent Orange As for exposure to Agent Orange, a Veteran who, during service, served in the Republic of Vietnam during the Vietnam era, beginning in January 1962 and ending in May 1975, shall be presumed to have been exposed during such service to herbicide agents, including a herbicide commonly referred to as Agent Orange. 38 U.S.C.A. § 1116(a)(3); 38 C.F.R. §§ 3.307, 3.309. If a Veteran was exposed to Agent Orange the following diseases will be presumed to have been incurred in service if manifest to a compensable degree within specified periods, even if there is no record of such disease during service: chloracne or other acneform disease consistent with chloracne, type 2 diabetes, Hodgkin's disease, chronic lymphocytic leukemia, multiple myeloma, non-Hodgkin's lymphoma, acute and subacute peripheral neuropathy, porphyria cutanea tarda, prostate cancer, respiratory cancers (cancer of the lung, bronchus, larynx, or trachea), and soft-tissue sarcoma (other than osteosarcoma, chondrosarcoma, Kaposi's sarcoma, or mesothelioma). 38 U.S.C.A. § 1116(a)(2); 38 C.F.R. §§3.307(a)(6), 3.309(e). Colon cancer, including adenocarcinoma, is not on the list of diseases subject to presumptive service connection due to exposure to Agent Orange. And the Secretary of VA has determined that a presumption of service connection based on exposure to Agent Orange used in the Republic of Vietnam during the Vietnam era is not warranted for any condition for which the Secretary has not specifically determined a presumption of service connection is warranted. Notice, 72 Fed. Reg. 32,395 (2007). Notwithstanding the aforementioned provisions relating to presumptive service connection, which arose out of the Veteran's Dioxin and Radiation Exposure Compensation Standards Act, Pub. L. No. 98-542, § 5, 98 Stat. 2 ,725, 2,727-29 (1984), and the Agent Orange Act of 1991, Pub. L. No. 102-4, § 2, 105 Stat. 11 (1991), a claimant is not precluded from establishing service connection with proof of direct causation. Combee v. Brown, 34 F.3d 1039, 1042 (Fed. Cir. 1994). As the Veteran served in Vietnam, he is presumed to have been exposed to Agent Orange. And as colon cancer is not on the list of diseases for which the presumption of service connection due to exposure to Agent Orange applies, the remaining question is whether the Veteran's fatal colon cancer is actually caused by exposure to Agent Orange under Combee. To the extent the Appellant associates the colon cancer is due to the Veteran's service, including Agent Orange exposure the Appellant as a lay person is competent to offer an opinion on a simple medical condition. Davidson v. Shinseki, 581 F.3d 1313, 1316 (Fed. Cir. 2009). In this case, the question of an association between the Veteran's colon cancer and service because it does not involve a simple medical condition and such an association cannot be determined by the Appellant based on an inference based on personal observation without having specialized education, training, or experience. 38 C.F.R. § 3.159. See Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007) (noting that sometimes the lay person will be competent to identify the condition where the condition is simple, for example a broken leg, and sometimes not, for example, a form of cancer). Where, as here, the determinative question is whether there is medical evidence of an association or link between a type of cancer and exposure to Agent Orange, the Board finds that a lay assertion on medical causation is not competent evidence and competent medical evidence is required to substantiate the claim. Grottveit v. Brown, 5 Vet. App. 91, 93 (1993), Competent medical evidence means evidence provided by a person who is qualified through education, training, or experience to offer a medical diagnosis or medical opinion. 38 C.F.R. § 3.159. As a lay person, the Appellant is not qualified through education, training, and expertise to offer an opinion on medical causation, where a lay assertion on medical causation is not competent evidence. Therefore, the Appellant's opinion is not competent evidence favorable to the claim. Turning to the competent and credible evidence of record on the question of causation, the opinion of nurse practitioner is evidence favorable to the claim when she concluded that the Veteran developed colon cancer due to exposure to Agent Orange. Against the claim is the opinion of the VA expert, who expressed a negative opinion as to the link between the Veteran's colon cancer and death and also cited medical literature. In addition, the evidence against the claim includes the Secretary's position that there is no positive association exists between exposure to Agent Orange and a Colon cancer. 38 U.S.C.A. § 1116 and 38 C.F.R. § 1.17. Under 38 U.S.C.A. § 1116(b)(3) , an association between the occurrence of a disease in humans and exposure to a herbicide agent shall be considered positive if the credible evidence for the association is equal to or outweighs the credible evidence against such an association. Under 38 U.S.C.A. § 1116(b) and 38 C.F.R. § 1.17, the Secretary of VA is required by law to issue a presumption of service connection when sound medical and scientific evidence shows a positive association between a disease and exposure to Agent Orange so that the Veteran would have to produce medical or scientific evidence of equal or greater weight than that relied upon by the National Academy of Sciences and the Secretary in finding that no positive association exists between exposure to Agent Orange and an unlisted disease, such as colon cancer. The Secretary has specifically determined there is not positive association between Agent Orange exposure and gastrointestinal or colorectal cancer which would include cancers of the colon. Notice, 72 Fed. Reg. 32,395-32, 407 (2007); and 75 Fed. Reg. 32540 (2010). The Board recognizes that greater weight may be placed on one physician's opinion over another depending on factors such as reasoning employed and whether or not, and the extent to which they reviewed the record. Gabrielson v. Brown, 7 Vet. App. 36, 40 1994). The probative value of a medical opinion is generally based on the scope of the examination or review, as well as the relative merits of the analytical findings, and the probative weight of a medical opinion may be reduced if the physician fails to explain the basis for an opinion. Sklar v. Brown, 5 Vet. App. 140, 146 (1993). Although the nurse practitioner is competent to offer an opinion as to the relationship between colon cancer and Agent Orange, the Board assigns her opinion a lesser value than that of the VA physician who issued an opinion in November 2010 as her expertise is not as extensive as that of a physician. See Sklar v. Brown, 5 Vet. App. 140, 146 (1993) (professional credentials and experience of opinion providers are properly considered in assigning probative value). Furthermore, although nurse practitioner Ahlemeyer had access to VA treatment records, there is no indication she reviewed the entire claims file including service treatment and personnel records. The VA examiner stated that he review the file. This is another factor that the Board has considered in assigning the nurse practitioner's opinion less probative weight than that of the VA examiner. See Nieves-Rodriguez v. Peake, 22 Vet. App. 295, 303 (2008) (generally, the claims file is the most complete source of all available records and it is what the adjudicator is looking at); Sims v. Nicholson, 19 Vet. App. 453, 458-59 (2006) (affirming Board finding that a private medical opinion was not entitled to probative weight because the examiner did not have the veteran's claims file to review). Here, there is no indication the nurse practitioner took into account the medical information available from the service treatment records, or the information available from the Veteran's personnel records such as the records demonstrating his actual duties. Nurse practitioner Ahlemeyer also did not account for the findings by the National Academy of Science referenced earlier which concluded there is no demonstrable relationship between Agent Orange exposure and colon cancer. The nurse practitioner's conclusion and citation to medical literature that colon cancer was related to Agent Orange/herbicide exposure does not equal or is greater than the body of evidence relied upon by the National Academy of Sciences and the Secretary in finding that no positive association exists between exposure to Agent Orange and gastrointestinal cancers or colorectal cancers. For this reason, the nurse practitioner's statement is not persuasive evidence that the Veteran's colon cancer was actually caused by exposure to Agent Orange under Combee. As for the notations by other health-care professionals that the Veteran was exposed to Agent Orange, history recorded by a medical professional, which is unenhanced by any additional comment does not constitute competent medical evidence in case of direct causation, that is, that exposure to Agent Orange actually caused small bowel cancer. LeShore v. Brown, 8 Vet. App. 406, 409 (1995). Further, VA has already conceded that the Veteran has been exposed to Agent Orange, but the key question is whether the fatal colon cancer is the result of the exposure to herbicides. Based upon the Board's review, none of the notations by health care providers, other than nurse practitioner Ahlemeyer's letters, appear to connect the colon cancer to herbicide exposure. To the extent the cancer was discovered in other areas of the Veteran's body such as the liver, lung, and adrenal gland, the death certificate lists colon cancer as the only cause of death. Also, the medical evidence attributes any cancer found in the liver, lungs, or adrenal gland as cancer metastized from the colon cancer. Stated another way, the Veteran only had one type of cancer, colon cancer, that metastasized to other areas of the body. A metastasis of a cancer not associated with herbicide exposure is not entitled to the presumption of service connection due to Agent Orange exposure. See VAOPGCPREC 18-97 (May 2, 1997) (metastasis represents the progress of the nonservice-connected primary cancer, and is affirmative evidence that the secondary cancer was not the result of some other cause, such as herbicide exposure). Furthermore, even if the cancer found in the liver or adrenal cancer was a primary cancer, the Secretary has specifically determined there is not positive association between Agent Orange exposure and cancers of the liver or the adrenal gland. Notice, 72 Fed. Reg. 32,395 (2007). As to the cancer found in the lung, although respiratory cancers are entitled to presumptive service connection under 38 C.F.R. § 3.309, the death certificate does not list lung cancer as a significant condition contributing to the Veteran's death and there is no medical evidence to suggest it played a role in his death. The Board notes that medical evidence suggests that the Veteran's extensive alcohol and tobacco use may have played a role in his colon cancer and there is evidence of tobacco and alcohol use in service. With respect to claims of service connection for a disability due to drug and alcohol abuse filed after October 31, 1990, the law prohibits an award of VA compensation for such disability, whether the claim is based on a theory of direct or secondary service connection. 38 U.S.C.A. §§ 105(a), 1110; 38 C.F.R. §§ 3.1(m), (n), 3.301, 3.310(a); VAOPGCPREC 11-96; VAOPGCPREC 2- 97; Libertine v. Brown, 9 Vet. App. 521, 523 (1996). Furthermore, the VA examiner stated the association between colon cancer and alcohol and tobacco use was weak. Nurse Ahlemeyer determined the alcohol and tobacco use resulted from the veteran trying to cope with PTSD. The Veteran, however, was not service connected for PTSD. He was service connected for a mood disorder that resulted from the stress of his physical disabilities. Finally, the evidence demonstrates that the Veteran's tobacco and alcohol abuse is long standing. Therefore, the Board assigns little weight to her opinion regarding the alcohol or tobacco use. The Appellant also argues that she should be accorded the benefit-of-the-doubt in this case as the medical evidence presents a reasonable doubt regarding the cause of the Veteran's death. The reasonable doubt doctrine, however, requires that there be a "substantial" doubt and "one within the range of probability as distinguished from pure speculation or remote possibility." 38 C.F.R. § 3.102. As previously articulated, the favorable opinion of the nurse practitioner was deemed of less probative value than the VA physician and the NAS opinion that there is no association between Agent Orange exposure and colon cancer. The Board finds that this case is not one for which reasonable doubt has been raised as there is not an approximate balance of positive and negative evidence because the Board is placing greater probative weight on the negative opinions of the VA physician and the NAS studies than the opinion of the nurse practitioner who treated the Veteran. For the above reasons, the preponderance of the evidence is against the claim that the Veteran's death was related to service or to a service-connected disability, and the benefit-of-the-doubt standard of proof does not apply. 38 U.S.C.A. § 5107(b). ORDER Entitlement to service connection for the cause of the Veteran's death is denied. ____________________________________________ ROBERT C. SCHARNBERGER Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs