Citation Nr: 21071426 Decision Date: 11/30/21 Archive Date: 11/30/21 DOCKET NO. 19-27 769 DATE: November 30, 2021 ORDER Entitlement to service connection for primary sclerosing cholangitis due to exposure to herbicide agents is granted. Entitlement to service connection for ulcerative colitis due to exposure to herbicide agents is granted. Entitlement to service connection for a liver transplant with scarring and residuals secondary to service-connected primary sclerosing cholangitis is granted. Entitlement to chronic immunosuppression secondary to service-connected liver transplant residuals is granted. Entitlement to service connection for chronic renal disease secondary to service-connected liver transplant residuals is granted. Entitlement to service connection for a colectomy secondary to service-connected ulcerative colitis is granted. REMANDED Entitlement to service connection for osteoporosis, claimed as low bone density, to include as secondary to chronic immunosuppression is remanded. Entitlement to service connection to squamous cell carcinoma, to include as secondary to exposure to herbicide agents and/or as secondary to the Veteran's service-connected disabilities to include chronic immunosuppression is remanded. FINDINGS OF FACT 1. The Veteran served aboard the U.S.S. Floyd B. Parks, which served in the coastal waters of Vietnam. 2. Resolving all reasonable doubt in favor of the Veteran, the evidence is at least in equipoise that his currently diagnosed primary sclerosing cholangitis was caused by his in-service exposure to herbicides. 3. Resolving all reasonable doubt in favor of the Veteran, the evidence is at least in equipoise that his currently diagnosed ulcerative colitis was caused by his in-service exposure to herbicides. 4. Resolving all reasonable doubt in favor of the Veteran, his liver transplant residuals are etiologically related to service, to include his service-connected primary sclerosing cholangitis. 5. Resolving all reasonable doubt in favor of the Veteran, his currently diagnosed chronic immunosuppression was caused by medications required to treat his service-connected liver transplant residuals. 6. Resolving all reasonable doubt in favor of the Veteran, his currently diagnosed chronic renal disease was caused by medications required to treat his service-connected liver transplant residuals. 7. Resolving all reasonable doubt in favor of the Veteran, his colectomy is etiologically related to service, to include his service-connected ulcerative colitis. CONCLUSIONS OF LAW 1. The criteria for entitlement to service connection for primary sclerosing cholangitis as due to exposure to herbicides while in-service have been met. 38 U.S.C. §§ 1110, 1116, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309. 2. The criteria for entitlement to service connection for ulcerative colitis as due to exposure to herbicides while in-service have been met. 38 U.S.C. §§ 1110, 1116, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309. 3. The criteria for entitlement to service connection for a liver transplant, as secondary to the Veteran's now service-connected primary sclerosing cholangitis, have been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.159, 3.310. 4. The criteria for entitlement to service connection for chronic immunosuppression, as secondary to the Veteran's now service-connected liver transplant, have been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.159, 3.310. 5. The criteria for entitlement to service connection for chronic renal disease, as secondary to the Veteran's now service-connected immunosuppression, have been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.159, 3.310. 6. The criteria for entitlement to service connection for a colectomy, as secondary to the Veteran's now service-connected ulcerative colitis, have been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.159, 3.310. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty in the United States Navy from August 1967 to November 1968. These matters come before the Board of Veterans' Appeals (Board) on appeal from a June 2018 rating decision of the Department of Veterans Affairs (VA) Regional Office (RO). In December 2020, the Veteran testified before the undersigned Veterans Law Judge at a video conference hearing. A transcript of the hearing is of record. Service Connection Service connection may be granted if the evidence demonstrates that a current disability resulted from an injury or disease incurred or aggravated during active military service. 38 U.S.C. § 1110; 38 C.F.R. § 3.303(a). In general, service connection requires: (1) evidence of a current disability; (2) medical, or in certain circumstances, lay evidence of an 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. See Shedden v. Principi, 381 F.3d 1163, 1166-67 (Fed. Cir. 2004). Service connection may be granted for any disease diagnosed after discharge when all evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d). In addition, service connection may be established on a secondary basis for a disability which is shown to be proximately due to or the result of a service-connected disease or injury. 38 C.F.R. § 3.310. Establishing service connection on a secondary basis requires evidence sufficient to show that a current disability exists and that the current disability was either caused by or aggravated by a service-connected disability. 38 C.F.R. § 3.310; Allen v. Brown, 7 Vet. App. 439 (1995). Service connection may be presumed for certain chronic diseases which develop to a compensable degree within one year after discharge from service, even though there is no evidence of such disease during the period of service. This presumption is rebuttable only by probative evidence to the contrary. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. § 3.307, 3.309(a). Where the evidence, regardless of its date, shows that the Veteran had a chronic condition in service or during an applicable presumption period and still has that chronic disability, service connection can be granted. This does not mean that any manifestations in service will permit service connection. To show chronic disease in service, a combination of manifestations sufficient to identify the disease entity, and sufficient observation to establish chronicity at the time, are required. As distinguished from merely isolated findings, or a diagnosis including the word chronic. When the disease entity is established, evidence of continuity is not required. 38 C.F.R. § 3.303(b). If there is no evidence of a chronic condition during service or an applicable presumptive period, then a showing of continuity of symptoms after service may serve as an alternative method of establishing service connection. 38 C.F.R. § 3.303(b). Continuity of symptoms may be established if a claimant can demonstrate (1) that a condition was noted during service; (2) evidence of post- service continuity of the same symptomatology and (3) medical or, in certain circumstances, lay evidence of a nexus between the present disability and the post-service symptomatology. If service connection is established by continuity of symptomatology, there must be medical evidence that relates a current condition to that symptomatology. Continuity of symptoms applies only to those conditions explicitly recognized as chronic. 38 C.F.R. § 3.309(a); Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2013). Further, a Veteran who during active military, naval, or air service served in the Republic of Vietnam during the period beginning January 9, 1962, and ending on May 7, 1975, shall be presumed to have been exposed during such service to an herbicide agent, unless there is affirmative evidence establishing that the Veteran was not exposed to any such agent. 38 U.S.C. § 1116 (f); 38 C.F.R. § 3.307 (a)(6)(iii). In order to benefit from the presumption of service connection for diseases associated with herbicide agent exposure, the Veteran must have one of the diseases enumerated in 38 C.F.R. § 3.309(e). However, diseases not enumerated in said regulation do not preclude service connection on a direct basis. See Combee v. Brown, 34 F.3d 1039,1045 (Fed. Cir. 1994). In Procopio v. Wilkie, 913 F.3d 1371,1380-81 (Fed. Cir. 2019) (en banc), the U.S. Appeals for the Federal Circuit (Federal Circuit) held that Veterans who "served in the 12 nautical mile territorial sea of the 'Republic of Vietnam' " are entitled to presumptive service connection under 38 U.S.C. § 1116 so long as they meet the section's other requirements. Id; see also 38 U.S.C. § 1116. The Blue Water Navy Vietnam Veterans Act of 2019 extended the presumption of exposure to herbicide agents to those veterans who served within the 12 nautical miles of Vietnam. See Blue Water Navy Vietnam Veterans Act of 2019, H.R. 299, 116th Cong. (2019). In the current matter, the Veteran is presumed to have been exposed to herbicides based on his nautical service. 1. Entitlement to service connection for primary sclerosing cholangitis due to exposure to herbicide agents The Veteran seeks service connection for his diagnosed primary sclerosing cholangitis, including as due to exposure to herbicides. The Veteran's exposure to herbicide agents has been conceded based on service in the territorial seas of the Republic of Vietnam. See May 2020 VA memorandum. Although primary sclerosing cholangitis is not one of the diseases presumptively associated with exposure to herbicide agents, service connection may still be granted on a direct basis if there is evidence that the disease was actually caused by herbicide agent exposure. Combee v. Brown, 34 F.3d 1039 (Fed. Cir. 1994). Private and VA treatment records reflect that the Veteran has a current diagnosis of primary sclerosing cholangitis. VA treatment records document the Veteran's continued treatment for the claimed condition. As such, a current disability has been shown. The Veteran submitted an April 2017 letter from his private physician, Dr. S.E.H. The examiner reviewed the Veteran's claims file and interviewed him, stating that primary sclerosing cholangitis is associated with exposure to chemicals, particularly fluorinated or chlorinated hydrocarbons, and have been shown to be more common in countries that have Superfund Clear-up sites. He opined that it is at least as likely as not that his exposure to Agent Orange led to the development of his currently diagnosed primary sclerosing cholangitis. In May 2018, the Veteran underwent a VA examination to determine to nature and etiology of his primary sclerosing cholangitis. Upon examination, the examiner confirmed a diagnosis of primary sclerosing cholangitis. He opined that the Veteran's primary sclerosing cholangitis is less likely than not incurred in or caused by the claimed in-service injury, event, or illness, to include as due to exposure to herbicide agents, stating that there is no medical rationale to support a connection between drinking brown water while in service and development of primary sclerosing cholangitis many years later. He further stated that the etiology of the Veteran's condition is general autoimmune, but there is no specific etiology or cause. The examiner listed other risk causes but he did not offer an analysis according to the specific facts of the Veteran's case. When an opinion does not express the right degree of certainty, does not provide a rationale, is conclusory, does not consider all of the relevant evidence of record including lay statements, or does not consider all raised theories of entitlement then the examination is inadequate. As such, the Board finds that the opinion is entitled to minimal probative weight. Steff v. Nicholson, 21 Vet. App. 120 (2007); Bloom v. West, 12 Vet. App. 185, 187 (1999); Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008); Combee v. Brown, 34 F.3rd 1039, 1043-44 (Fed. Cir. 1994). Based on the foregoing and resolving all reasonable doubt in favor of the Veteran, the Board finds that the evidence supports a finding that the Veteran's primary sclerosing cholangitis was at least as likely as not related to his active-duty service, to include his exposure to herbicides while in service. Though the Veteran is not afforded the presumptive service connection associations of 38 C.F.R. § 3.309, direct service connection may still be established by showing that his primary sclerosing cholangitis was in fact causally linked to such exposure to herbicides. Based on the evidence in the Veteran's claims file and the opinion of the Veteran's private physician, the Board finds that such a link was established. The physician was clear in his finding that the Veteran's primary sclerosing cholangitis was at least as likely as not related to his in-service exposure to herbicides. The Board finds the April 2017 letter highly probative to the issue of whether the Veteran's primary sclerosing cholangitis was related to his active service. The Board finds that the physician examiner possessed the necessary education, training, and expertise to provide the opinion. Grottveit v. Brown, 5 Vet. App. 91, 93 (1993). In providing his opinion on the etiology of the Veteran's primary sclerosing cholangitis, the examiner relied upon examination of the Veteran, knowledge of service treatment records and post-service medical records. Given the evidence and legal authority discussed above, to include the probative April 2018 medical opinion, and resolving all reasonable doubt in the Veteran's favor, the Board finds that service connection for the Veteran's primary sclerosing cholangitis is warranted. 2. Entitlement to service connection for ulcerative colitis due to exposure to herbicide agents The Veteran seeks service connection for his diagnosed ulcerative colitis, including as due to exposure to herbicides. The Veteran's exposure to herbicide agents has been conceded based on service in the territorial seas of the Republic of Vietnam. See May 2020 VA memorandum. Although ulcerative colitis is not one of the diseases presumptively associated with exposure to herbicide agents, service connection may still be granted on a direct basis if there is evidence that the disease was actually caused by herbicide agent exposure. Combee v. Brown, 34 F.3d 1039 (Fed. Cir. 1994). Private and VA treatment records reflect that the Veteran has a current diagnosis of ulcerative colitis. VA treatment records document the Veteran's continued treatment for the claimed condition. As such, a current disability has been shown. The Veteran submitted an April 2017 letter from his private physician, Dr. S.E.L. The examiner reviewed the Veteran's claims file and interviewed him, stating that ulcerative colitis is associated with exposure to chemicals, particularly fluorinated or chlorinated hydrocarbons, and have been shown to be more common in countries that have Superfund Clear-up sites. He opined that it is at least as likely as not that his exposure to Agent Orange led to the development of his currently diagnosed ulcerative colitis. In May 2018, the Veteran underwent a VA examination to determine to nature and etiology of his ulcerative colitis. Upon examination, the examiner confirmed a diagnosis of ulcerative colitis. He opined that the Veteran's ulcerative colitis is less likely than not due to the Veteran's now service-connected primary sclerosing cholangitis, stating that the conditions of ulcerative colitis and primary sclerosing cholangitis are unrelated in the medical literature and that the ulcerative colitis occurred prior to the primary sclerosing cholangitis. The Board finds this opinion to be inadequate. The examiner did not address all theories of entitlement to service connection raised by the record, to include entitlement to service connection for ulcerative colitis as due to in-service exposure to herbicide agents. Moreover, the examiner's conclusory statement offered no rationale and is therefore inadequate. When an opinion does not express the right degree of certainty, does not provide a rationale, is conclusory, does not consider all of the relevant evidence of record including lay statements, or does not consider all raised theories of entitlement then the examination is inadequate. As such, the Board finds that the opinion is entitled to minimal probative weight. Steff v. Nicholson, 21 Vet. App. 120 (2007); Bloom v. West, 12 Vet. App. 185, 187 (1999); Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008); Combee v. Brown, 34 F.3rd 1039, 1043-44 (Fed. Cir. 1994). Based on the foregoing and resolving all reasonable doubt in favor of the Veteran, the Board finds that the evidence supports a finding that the Veteran's ulcerative colitis was at least as likely as not related to his active-duty service, to include his exposure to herbicides while in service. Though the Veteran is not afforded the presumptive service connection associations of 38 C.F.R. § 3.309, direct service connection may still be established by showing that his ulcerative colitis was in fact causally linked to such exposure to herbicides. Based on the evidence in the Veteran's claims file and the opinion of the Veteran's private physician, the Board finds that such a link was established. The physician was clear in his finding that the Veteran's ulcerative colitis was at least as likely as not related to his in-service exposure to herbicides. The Board finds the April 2017 letter highly probative to the issue of whether the ulcerative colitis was related to his active service. The Board finds that the physician examiner possessed the necessary education, training, and expertise to provide the opinion. Grottveit v. Brown, 5 Vet. App. 91, 93 (1993). In providing his opinion on the etiology of the Veteran's ulcerative colitis, the examiner relied upon examination of the Veteran, knowledge of service treatment records and post-service medical records. Given the evidence and legal authority discussed above, to include the probative April 2018 medical opinion, and resolving all reasonable doubt in the Veteran's favor, the Board finds that service connection for the Veteran's ulcerative colitis is warranted. 3. Entitlement to service connection for a liver transplant with scarring and residuals secondary to service-connected primary sclerosing cholangitis The Veteran contends that his liver transplant is etiologically related to service. Specifically, he argues that his liver transplant is caused or aggravated by his now service-connected primary sclerosing cholangitis. A May 2018 VA liver conditions examination notes that the Veteran underwent a liver transplant in April 2003. This is also reflected in the Veteran's VA and private treatment records. Further, service connection for primary sclerosing cholangitis has been granted herein. As such, the dispositive issue is whether the liver disability is causally related to the Veteran's primary sclerosing cholangitis. 38 C.F.R. § 3.310. In April 2003 VA treatment records from the Veteran's liver transplant, the need for the procedure is attributed to the Veteran's to the Veteran's primary sclerosing cholangitis, noting that the Veteran had progressive liver dysfunction since his diagnosis of primary sclerosing cholangitis in 1982, and a February 2016 VA treatment record noted that the liver transplant was due to the Veteran's primary sclerosing cholangitis. There is no evidence either of these assessments are not competent or credible, and therefore the Board finds they are entitled to significant probative weight. Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008). No other opinions concerning the etiology of the liver transplant are of record. Based on the foregoing, and in the interest of affording the Veteran the full benefit of the doubt, the evidence shows that the Veteran's liver transplant is related to his service-connected primary sclerosing cholangitis. As such, service connection for a liver transplant as secondary to primary sclerosing cholangitis is granted. 38 C.F.R. §§ 3.102, 3.310. 4. Entitlement to chronic immunosuppression secondary to service-connected liver transplant residuals The Veteran contends that his chronic immunosuppression is etiologically related to service. Specifically, he argues that his chronic immunosuppression is caused or aggravated by his now service-connected primary sclerosing cholangitis. Private and VA treatment records reflect that the Veteran has a current diagnosis of chronic immunosuppression. VA treatment records document the Veteran's continued treatment for the claimed condition. As such, a current disability has been shown. Further, service connection for primary sclerosing cholangitis has been granted herein. As such, the dispositive issue is whether the liver disability is causally related to the Veteran's primary sclerosing cholangitis. 38 C.F.R. § 3.310. Following a May 2018 VA examination, the VA examiner opined that while the Veteran is on immunosuppressant drugs, there is no history consistent with active immunosuppression, such as unusual infections. He further stated that although the Veteran does have infection, they are related to the total colectomy secondary to the ulcerative colitis. The VA examiner's conclusory statement offered no rationale and is therefore inadequate. Therefore, the Board finds this opinion to be conclusory and unsupported by sufficient rationale. See Nieves-Rodriguez v. Peake, 22 Vet. App. 295, 301 (2008); see also Stefl v. Nicholson, 21 Vet. App. 120, 124-25 (2007) (a mere conclusory opinion is insufficient to allow the Board to make an informed decision as to the weight to assign to a medical opinion). In numerous private treatment records, including in April 2009 and June 2016, the Veteran's private treating physicians attributed the Veteran's chronic immunosuppression to medications required due to the Veteran's status post liver transplant. There is no evidence either of these assessments are not competent or credible, and therefore the Board finds they are entitled to significant probative weight. Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008). No other opinions concerning the etiology of the liver transplant are of record. Based on the foregoing, and in the interest of affording the Veteran the full benefit of the doubt, the evidence shows that the Veteran's chronic immunosuppression is causally related to his service-connected primary sclerosing cholangitis and resultant liver transplant. As such, service connection for chronic immunosuppression as secondary to the now service-connected primary sclerosing cholangitis and medication required for the resultant service-connected liver transplant is granted. 38 C.F.R. §§ 3.102, 3.310. 5. Entitlement to service connection for chronic renal disease secondary to service-connected liver transplant residuals The Veteran contends that his chronic renal disease is etiologically related to service. Specifically, he argues that his chronic renal disease is caused or aggravated by his now service-connected primary sclerosing cholangitis and related chronic immunosuppression due to medications required following his April 2003 liver transplant. Private and VA treatment records reflect that the Veteran has a current diagnosis of chronic renal disease. VA treatment records document the Veteran's continued treatment for the claimed condition. As such, a current disability has been shown. Further, service connection for liver transplant residuals has been granted herein. As such, the dispositive issue is whether the liver disability is causally related to the Veteran's primary sclerosing cholangitis and/or other now service-connected disabilities. 38 C.F.R. § 3.310. Following a May 2018 VA examination, the VA examiner that the available records seem to indicate that the mild renal insufficiency is secondary to the immunosuppressants for the primary sclerosing cholangitis. However, I was not able to find any direct documentation, opining that this was possibly "hearsay reported based on the veteran's statements." However, a review of the Veteran's private treatment records shows that both February 2016 and May 2016 private treatment records, a private treating physician outlines the conclusion that the Veteran's immunosuppressive medications required following his liver transplant are the cause of his chronic renal disease. Therefore, the Board finds the VA examiner's opinion to be inadequate. Reonal v. Brown, 5 Vet. App. 458, 460 (1993) (medical opinions based on an incomplete or inaccurate factual premise are not probative). Therefore, the May 2018 opinion is inadequate. As such, the Board finds that the opinion is entitled to minimal probative weight. There is no evidence either of the assessments by the Veteran's private treating physicians regarding the nature and etiology of the Veteran's chronic renal disease are not competent or credible, and therefore the Board finds they are entitled to significant probative weight. Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008). No other opinions concerning the etiology of the liver transplant are of record. Based on the foregoing, and in the interest of affording the Veteran the full benefit of the doubt, the evidence shows that the Veteran's chronic renal disease is causally related to his now service-connected primary sclerosing cholangitis and immunosuppressive medication required due to his liver transplant. As such, service connection for chronic renal disease as secondary to primary sclerosing cholangitis and medication required for the resultant liver transplant is granted. 38 C.F.R. §§ 3.102, 3.310. 6. Entitlement to service connection for a colectomy secondary to service-connected ulcerative colitis The Veteran contends that his colectomy is etiologically related to service. Specifically, he argues that his colectomy is caused or aggravated by his now service-connected ulcerative colitis. A May 2018 VA intestinal surgeries examination notes that the Veteran underwent a total colectomy in 1996. This is also reflected in the Veteran's VA and private treatment records. Further, service connection for ulcerative colitis has been granted herein. As such, the dispositive issue is whether the colectomy is causally related to the Veteran's ulcerative colitis. 38 C.F.R. § 3.310. In the May 2018 VA intestinal surgeries examination, the VA examiner stated that the Veteran's colectomy was secondary to ulcerative colitis. Moreover, numerous VA and private treatment records, including an April 2003 VA treatment record and October 2008 private treatment record notes that the colectomy was due to the Veteran's ulcerative colitis. There is no evidence any of these assessments are not competent or credible, and therefore the Board finds they are entitled to significant probative weight. Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008). No other opinions concerning the etiology of the colectomy are of record. Based on the foregoing, and in the interest of affording the Veteran the full benefit of the doubt, the evidence shows that the Veteran's total colectomy is causally related to his now service-connected ulcerative colitis. As such, service connection for total colectomy as secondary to now service-connected ulcerative colitis is granted. 38 C.F.R. §§ 3.102, 3.310. REASONS FOR REMAND Unfortunately, the remaining claims must be remanded for further development. Although the Board regrets the additional delay, it is necessary to ensure that there is a complete record upon which to decide these matters so that the Veteran is afforded every possible consideration. 1. Entitlement to service connection for osteoporosis, claimed as low bone density, to include as secondary to chronic immunosuppression is remanded. The Board notes that the Veteran has consistently asserted that he has osteoporosis, claimed as bone density loss, that is etiologically related to his active service. In that regard, he asserted that he has osteoporosis as secondary to his now service-connected chronic immunosuppression. Indeed, the Veteran's post-service treatment records indicate he has osteoporosis. In light of the Veteran's statements and his current diagnosis for osteoporosis, the Board concludes that the Veteran should be afforded a VA examination to determine the nature and etiology of osteoporosis, to include whether the disability was caused by or aggravated by any service-connected disability to include chronic immunosuppression. 38 U.S.C. § 5103A(d); McLendon v. Nicholson, 20 Vet. App. 79, 83 (2006). 2. Entitlement to service connection to squamous cell carcinoma, to include as secondary to exposure to herbicide agents and/or as secondary to the Veteran's service-connected disabilities to include chronic immunosuppression The Veteran seeks service connection for nonmelanoma skin cancer, which he contends is due to exposure to herbicide agents and/or his now service-connected chronic immunosuppression. VA treatment records show that he has been treated for multiple occurrences of squamous cell carcinomas on his right forearm and scalp during the period of appeal. The Board notes that squamous cell carcinoma is not among the diseases listed as presumptively associated with herbicide exposure; however, service connection may still be granted on a direct basis if there is evidence that a disease is related to herbicide agent exposure. See 38 C.F.R. § 3.309(e); Combee v. Brown, 34 F.3d 1039 (Fed. Cir. 1994). The Veteran underwent a VA skin diseases examination in May 2018 to determine the nature and etiology of his squamous cell carcinoma. The VA examiner confirmed multiple occurrences of squamous cell carcinomas on his right forearm and scalp. The examiner then stated that there is no known medical rationale to support a connection between immunosuppression and the squamous cell carcinoma, noting that primary risk factor for this type of cancer is sun exposure. The Board finds this medical opinion to be inadequate. First, the examiner did not address all theories of entitlement to service connection raised by the record, to include entitlement to service connection for squamous cell carcinoma as due to in-service exposure to herbicide agents. Next, the Board finds the examiner's opinion to be inadequate as it does not contain a sufficient medical rationale to support its conclusion. Nieves-Rodriguez v. Peake, 22 Vet. App. 295, 302-04 (2008) (holding that it is the factually accurate, fully articulated, and sound reasoning for the conclusion that contributes to the probative value of a medical opinion); see also Stefl v. Nicholson, 21 Vet. App. 120, 124-25 (2007) (a mere conclusory opinion is insufficient to allow the Board to make an informed decision as to the weight to assign to a medical opinion). As such, the Board finds that the opinion is entitled to minimal probative weight. The Board acknowledges a November 2017 letter from the Veteran's private treating physician, Dr. J.H., stating that the Veteran is on chronic immunosuppressant medications which may be associated with an increased risk of skin malignancy. Although favorable to the Veteran, the Board is unable to use this opinion as a basis to grant service connection. The use of the words "possible," "may," or "can be" make a doctor's opinion speculative in nature. See Bostain v. West, 11 Vet. App. 124, 12728 (1998) (quoting Obert v. Brown, 5 Vet. App. 30, 33 (1993)). It is well established that medical opinions that are speculative, general, or inconclusive in nature do not provide a sufficient basis upon which to support a claim. McLendon v. Nicholson, 20 Vet. App. 79, 85 (2006). In light of the above, the Board finds that the record still does not contain a medical opinion that is adequate to allow the Board to fairly adjudicate the Veteran's claim. Therefore, the Board finds a remand is required to obtain an addendum medical opinion to determine the nature and etiology of his squamous cell carcinoma. On remand, an addendum medical opinion must be obtained that is adequate for the Board to make an informed decision on the Veteran's claim. See Barr v. Nicholson, 21 Vet. App. 303, 311-12 (2007); Douglas v. Shinseki, 23 Vet. App. 19, 26 (2009). Moreover, during the December 2020 hearing, the Veteran indicated that he receives on-going treatment for his squamous cell carcinoma from a private dermatologist. While some relevant private treatment records are associated with the file, the most recent records are from approximately 2013 or 2014. As there is an indication that there may be further outstanding private treatment records relevant to the Veteran's claim for service connection for squamous cell carcinoma, a remand is necessary so that the Veteran can be asked to either submit any relevant records or authorize them for release. Accordingly, the matters are REMANDED for the following action: Osteoporosis 1. Schedule the Veteran for a VA examination by an examiner with sufficient expertise to determine the nature and etiology of the Veteran's osteoporosis. The examiner should review the claims file and indicate that review in the report. Any indicated studies should be performed. Thereafter, the examiner is asked to provide a fully articulated medical opinion addressing the following: (a) Is it at least as likely as not (50 percent or greater probability) that the Veteran's osteoporosis was incurred in or caused by an in-service injury, event, or illness, to include presumed exposure to herbicide agents? (b) Is it at least as likely as not (50 percent probability or greater) that the Veteran's osteoporosis is caused by any of the Veteran's service-connected disabilities, including chronic immunosuppression? (c) Is it at least as likely as not (50 percent probability or greater) that the Veteran's squamous cell carcinoma is aggravated by (increased in severity beyond its natural progression) any of the Veteran's service-connected disabilities, including chronic immunosuppression? Squamous Cell Carcinoma 1. Contact the Veteran and request that he submit or authorize for release all private treatment records relevant to his squamous cell carcinoma. For private treatment records, make at least two (2) attempts to obtain records from any identified sources. If any such records are unavailable, inform the Veteran and afford him an opportunity to submit any copies in his possession. For all records authorized for release, if the search for these records is negative, that should be documented in the claims file, and the Veteran must be informed of this in writing in accordance with 38 C.F.R. § 3.159(e). 2. Then, forward the Veteran's claims file to a qualified VA examiner, who has not yet provided an opinion in this case, to provide an addendum opinion. VA examinations should not be scheduled unless deemed necessary by the examiner or otherwise required by the evidence. The examiner must review the claims file in its entirety, to include a copy of this REMAND, and that review must be noted in the report. Thereafter, the examiner is asked to provide a fully articulated medical opinion addressing the following: (a) Is it at least as likely as not (50 percent or greater probability) that the Veteran's squamous cell carcinoma was incurred in or caused by an in-service injury, event, or illness, to include presumed exposure to herbicide agents? (b) Is it at least as likely as not (50 percent probability or greater) that the Veteran's squamous cell carcinoma is caused by any of the Veteran's service-connected disabilities, including chronic immunosuppression? (c) Is it at least as likely as not (50 percent probability or greater) that the Veteran's squamous cell carcinoma is aggravated by (increased in severity beyond its natural progression) any of the Veteran's service-connected disabilities, including chronic immunosuppression? In responding to the above, the examiner must opine as to whether the skin condition is directly related to the Veteran's presumed herbicide agent exposure during service. A medical opinion that concludes that a disease is not related to herbicide exposure solely because there is no presumption of service connection is inadequate. The examiner is reminded that the term "at least as likely as not" does not mean "within the realm of possibility." Rather, it means that the weight of the medical evidence both for and against the claim is so evenly divided that it is as medically sound to find in favor of the claim as it is to find against it. The examiner is advised that the lack of documented treatment for the claimed disability during service cannot serve as the sole basis for a negative finding. The examiner is advised that the Veteran is competent to report his medical history and must be considered and weighed in making the determination as to whether a nexus exists between the claimed diseases and military service. The examiner must provide a complete rationale for any opinion expressed. If the examiner is unable to provide an opinion without resorting to speculation, he or she should fully explain why that is so. LESLEY A. REIN Veterans Law Judge Board of Veterans' Appeals Attorney for the Board Rosenthal, Ariana 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.