Citation Nr: 1756120 Decision Date: 12/06/17 Archive Date: 12/15/17 DOCKET NO. 11-12 070A ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in Waco, Texas THE ISSUES 1. Entitlement to service connection for cholangiocarcinoma/bile duct cancer, to include as due to Agent Orange exposure, for accrued benefits purposes. 2. Entitlement to service connection for cause of the Veteran's death. REPRESENTATION Appellant represented by: Katrina J. Eagle, Attorney ATTORNEY FOR THE BOARD A. N. Nolley, Associate Counsel INTRODUCTION The Veteran had active service in the United States Marine Corps from November 1968 to August 1971, and from April 1974 to September 1991. This appeal comes before the Board of Veterans' Appeals (Board) from a March 2009 rating decision issued by the Department of Veterans Affairs (VA) Regional Office (RO) in Waco, Texas. The Veteran served in the Republic of Vietnam and was the recipient of the Combat Action Ribbon. Unfortunately, the Veteran passed away in September 2009. The appellant is the surviving spouse and was substituted with regard to the claim on appeal. FINDINGS OF FACT 1. The Veteran served in the Republic of Vietnam during the Vietnam Era and is therefore presumed to have been exposed to herbicides. 2. The most probative evidence of record shows that the Veteran's bile duct cancer was causally related to service. 3. The Veteran died in September 2009 from cholangiocarcinoma. CONCLUSIONS OF LAW 1. The criteria for service connection for bile duct cancer have been met. 38 U.S.C.A. § 1110; 5107(b) (West 2014); 38 C.F.R. §§ 3.303, 3.307, 3.309 (2017). 2. The criteria for service connection for cause of the Veteran's death are met. 38 U.S.C.A. §§ 1310, 5107 (West 2014); 38 C.F.R. §§ 3.102, 3.312 (2017). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS Duties to Notify and Assist As explained below, the Board has determined that the evidence currently of record is sufficient to substantiate the Veteran's claims on appeal. Therefore, no further development is required under 38 U.S.C.A. §§ 5103, 5103A (West 2014) or 38 C.F.R. § 3.159 (2017). Law and Analysis The appellant asserted that service connection is warranted for the Veteran's bile duct cancer. She asserted that the Veteran was exposed to food and water borne parasites while serving in Vietnam. The appellant submitted various buddy statements regarding the Veteran's issues with loose stools and chills since he returned from Vietnam. In addition, the appellant submitted medical evidence to show that the Veteran's bile duct cancer was caused by his presumed exposure to Agent Orange. Following a thorough review of all the evidence of record, and resolving all doubt in the Veteran's favor, the Board finds that service connection for bile duct cancer is warranted. Service connection is granted for disability resulting from disease or injury incurred in or aggravated by active duty. 38 U.S.C.A. § 1131; 38 C.F.R. § 3.303. Service connection may 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). If a veteran was exposed to an herbicide agent during active military, naval, or air service, the diseases listed under 38 C.F.R. § 3.309 (e) shall be service-connected if the requirements of 38 C.F.R. § 3.307 (a)(6) are met, even though there is no record of such disease during service, provided further that the rebuttable presumption provisions of 38 C.F.R. § 3.307 (d) are also satisfied. The list of diseases associated with exposure to certain herbicide agents is as follows: AL amyloidosis; chloracne or other acneform disease consistent with chloracne; Type 2 diabetes (also known as Type II diabetes mellitus or adult-onset diabetes); Hodgkin's disease; ischemic heart disease; all chronic B-cell leukemias; multiple myeloma; non-Hodgkin's lymphoma; Parkinson's disease; early-onset 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 C.F.R. § 3.309 (e). The medical evidence includes a diagnosis of cholangiocarcinoma. As such, the Board finds the evidence does not reflect a diagnosis of a presumptive disease that results from exposure to herbicides. See 38 C.F.R. § 3.309 (e). Therefore, service connection for cholangiocarcinoma may not be granted on a presumptive basis. Notwithstanding the presumption provisions, a veteran is not precluded from establishing service connection for disability due to herbicide agent exposure with proof of actual direct causation. Combee v. Brown, 34 F.3d 1039, 1042 (Fed. Cir. 1994). To establish service connection for the cause of the veteran's death, the evidence must show that disability incurred in or aggravated by service either caused or contributed substantially or materially to the cause of death. For a service-connected disability to be the cause of death, it must singly or with some other condition be the immediate or underlying cause or be etiologically related thereto. For a service-connected disability to constitute a contributory cause, it is not sufficient to show that it casually shared in producing death but rather it must be shown that there was a causal connection. 38 U.S.C.A. § 1310; 38 C.F.R. § 3.312. The medical evidence includes a diagnosis of cholangiocarcinoma in September 2008. Service treatment records are negative for a diagnosis of bile duct cancer. An August 1970 service treatment record documented the Veteran's complaints of stomach cramps, headaches, diarrhea, and general malaise. It was noted that he probably had malaria. His military personnel records confirmed that the Veteran served in the Republic of Vietnam from February 1970 to January 1971. Prior to his death, the Veteran provided details regarding his experiences in Vietnam. He recalled a serious gastrointestinal illness shortly after he arrived in Vietnam. He reported that a medic removed a boil and a large worm that was buried in the skin of his forearm. He stated that he drank, swam, and bathed in water from rivers, lakes, creeks, and even the impressions left from tire marks. He also stated that he often had to prepare his food without heat. He explained that clarification tablets were not always available. The medical evidence includes conflicting competent etiological opinions from a VA examiner, a private doctor, and the Veteran's VA oncologist. In July 2016, the Veteran's VA oncologist, K.C., M.D. opined that it was as likely as not that his exposure to parasites contributed to his development of cholangiocarcinoma, which eventually took his life. Dr. C. noted that the Veteran was likely exposed to food and water borne parasites, known as liver flukes. Dr. C. explained that parasitic infection was one of the established risk factors for cholangiocarcinoma. Dr. C. also noted that parasites such as clonorchi sinesis and Opisthorchis viverrini are endemic in Vietnam and are causally related to cholangiocarcinoma. A VA medical opinion was obtained in August 2016. The examiner concluded that medical literature did not show an association between mosquitoes or mosquito borne disease, including malaria, and cholangiocarcinoma. With respect to the assertion that a parasite infection caused the Veteran's cholangiocarcinoma, the VA examiner acknowledged that there was an association between liver flukes and cholangiocarcinoma. The VA examiner also acknowledged that individuals infected with liver flukes are asymptomatic and have a benign course. It was noted that chronic symptoms could occur late in the course of the infection and usually involve serious complications such as cholangiocarcinoma, cholangitis, and cholangiohepatits. Such complications result from chronic irritation to the epithelial cells and generally develop after the third decade of life. However, the VA examiner concluded that the Veteran did not have any symptoms of a liver fluke infection. The examiner noted that the Veteran separated from service in 1991 and had no symptoms of a parasite infection during service. He also did not have any symptoms until August 2008, just before his cancer diagnosis. Therefore, the examiner concluded that it was less likely than not that the Veteran had any parasitic fluke type infection, especially which remained asymptomatic without any evidence until 2008. The appellant submitted an October 2017 private medical opinion by J.B., M.D. Dr. B. opined that it was at least as likely as not that the Veteran's cholangiocarcinoma, the most common and aggressive cancer of the biliary tract, was caused by his in-service exposure to dioxin in Agent Orange and liver flukes. It was noted that the Veteran's risk factor for cholangiocarcinoma was a liver fluke infection from water in Vietnam, specifically his consumption of uncooked fish present in the water, which was the most common way the water borne parasite entered the body in Asia. The Veteran's report of dysentery and a boil on his arm that contained a worm was evidence that the Veteran ingested a water borne parasite. Therefore, Dr. B. concluded that based on the extreme conditions in Vietnam, the Veteran became infected with liver flukes which significantly contributed to his cholangiocarcinoma. In addressing the conflicting August 2016 VA medical opinion, Dr. B. stated that the Veteran did not show symptoms of liver fluke parasites post service because the effects of parasitic infections were typically subclinical, thereby avoiding detection, and then lie dormant for decades. Dr. B. also opined that there was a very likely causal relationship between the Veteran's exposure to dioxin in Agent Orange and the development of cholangiocarcinoma. Dr. B. stated that Agent Orange exposure caused insulin resistance, which contributed to the development of a number of different cancers. Specifically, the Veteran's obesity, hypertension, increased cholesterol, and increased blood glucose, indicated that the Veteran had hyperlipidemia and early diabetes. Dr. B. explained that weight gain due to Agent Orange, accelerated the onset of his diabetes, and that his hypertension, hyperlipidemia, diabetes, and insulin resistance, were components of Metabolic Syndrome, which is associated with an increased susceptibility to cancer. Medical literature was also referenced for the conclusion that elevated insulin levels foster an environment that promotes the development of a number of neoplasms, including those of the biliary tract, by promoting the production and release of growth-promoting hormones such as insulin-like growth factor-1. Dr. B. noted that the insulin-like growth factor-1 was shown to activate carcinogenic pathways in malignant cholangiocytes that line the biliary tract. Finally, Dr. B. noted that the studies completed by the Institute of Medicine demonstrate that dioxin is a carcinogen for the entire hepatic-biliary system and that the liver and biliary tract are contiguous tissues and share exposure to the same or similar toxic substances. Both hepatocytes and cholangiocytes can detoxify and eliminate many potential harmful substances from the body. Dr. B. stated that the biliary tract is a critical conduit through which potential carcinogens like dioxin exits the body, but can also internalize toxic substances in the process. After considering the conflicting medical opinions, the Board finds that the Veteran is entitled to service connection for bile duct cancer. In cases where there are conflicting statements or opinions from medical professionals, it is within the Board's province to weigh the probative value of those opinions. Guerrieri v. Brown, 4 Vet. App. 467, 470-71 (1993) (holding that the credibility and weight to be attached to medical opinions is within the province of the adjudicators). 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 expert's qualifications and analytical findings. See Sklar v. Brown, 5 Vet. App. 140 (1993). So long as the Board provides an adequate reason or basis for doing so, the Board does not err by favoring one competent medical opinion over another. See Owens v. Brown, 7 Vet. App. 429, 433 (1995). The VA benefits system does not favor the opinion of a VA examiner over a private examiner, or vice versa. See 38 U.S.C.A. § 5125 (West 2014); White v. Principi, 243 F.3d 1378, 1381 (Fed. Cir. 2001) (declining to adopt the treating physician rule for adjudicating VA benefits). Regardless of the source, an examination report must minimally meet the requirement of being sufficiently complete to be adequate for the purpose of adjudicating the claim. See 38 U.S.C.A. § 5125; 38 C.F.R. § 4.2 (2017). The Board notes that the VA examiner, Dr. C., and Dr. B. all agreed that exposure to water-borne parasites, known as liver flukes, was a known risk factor for cholangiocarcinoma. The August 2016 VA examiner and Dr. B. both acknowledged that liver fluke infections can remain asymptomatic for many decades. The August 2016 VA examiner concluded that the Veteran did not have liver flukes based on his lack of symptoms for many years after service. The Board affords significant probative value to the opinion provided by Dr. B. Dr. B., unlike the VA examiner, considered the Veteran's gastrointestinal symptoms in service and the Veteran's statements that he had a boil on his arm with a worm in it during his service in Vietnam. Furthermore, the Board affords probative value to Dr. B.'s opinion regarding the association between cholangiocarcinoma and the dioxin in Agent Orange. There is no other medical opinion of record addressing the relationship between cholangiocarcinoma and Agent Orange. Accordingly, the Board affords significant probative value to the etiological opinion of Dr. B. The opinion was based on a review of the Veteran's medical records and medical and scientific literature. Dr. B. also provided a clear conclusion with a reasoned medical explanation. Accordingly, service connection for bile duct cancer is warranted, as the most probative evidence shows that the Veteran's bile duct cancer was causally related to his active duty service. Gilbert v. Derwinski, 1 Vet. App. 49 (1990). The Veteran's October 2009 death certificate indicates that he died from progressive cholangiocarcinoma. As determined above, service connection for the Veteran's bile duct cancer is warranted. Accordingly, service connection for the cause of the Veteran's death is also warranted. ORDER Service connection for bile duct cancer is granted. Service connection for the cause of the Veteran's death is granted. ____________________________________________ B. MULLINS Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs