Citation Nr: 21006148 Decision Date: 02/03/21 Archive Date: 02/03/21 DOCKET NO. 19-33 507 DATE: February 3, 2021 ORDER Entitlement to service connection for rectal cancer, as due to herbicide exposure is granted. Entitlement to service connection for oral cancer, as due to herbicide exposure is granted. Entitlement to service connection for peripheral neuropathy of the left upper extremity, secondary to chemotherapy treatment is granted. Entitlement to service connection for peripheral neuropathy of the right upper extremity, secondary to chemotherapy treatment is granted. Entitlement to service connection for peripheral neuropathy of the left lower extremity, secondary to chemotherapy treatment is granted. Entitlement to service connection for peripheral neuropathy of the right lower extremity, secondary to chemotherapy treatment is granted. FINDINGS OF FACT 1. The Veteran is presumed to have been exposed to herbicide agents during active duty. 2. Resolving reasonable doubt in favor of the Veteran, his rectal cancer is related to in-service herbicide exposure. 3. Resolving reasonable doubt in favor of the Veteran, his oral cancer is related to in-service herbicide exposure. 4. The Veteran’s peripheral neuropathy of the left upper extremity is secondary to chemotherapy treatment for rectal cancer. 5. The Veteran’s peripheral neuropathy of the right upper extremity is secondary to chemotherapy treatment for rectal cancer. 6. The Veteran’s peripheral neuropathy of the left lower extremity is secondary to chemotherapy treatment for rectal cancer. 7. The Veteran’s peripheral neuropathy of the right lower extremity is secondary to chemotherapy treatment for rectal cancer. CONCLUSIONS OF LAW 1. The criteria for service connection for rectal cancer have been met. 38 U.S.C. §§ 1110, 1116, 1116A, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309. 2. The criteria for service connection for oral cancer have been met. 38 U.S.C. §§ 1110, 1116, 1116A, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309. 3. The criteria for service connection for peripheral neuropathy of the left upper extremity have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. 4. The criteria for service connection for peripheral neuropathy of the right upper extremity have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. 5. The criteria for service connection for peripheral neuropathy of the left lower extremity have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. 6. The criteria for service connection for peripheral neuropathy of the right lower extremity have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty from November 1966 to August 1968. This matter comes before the Board of Veterans’ Appeals (Board) on appeal from a June 2018 rating decision issued by a Department of Veterans Affairs (VA) Regional Office (RO). In January 2021, the Veteran testified at a virtual hearing before the undersigned Veterans Law Judge (VLJ). A transcript of that proceeding has been associated with the record. 1. Entitlement to service connection for rectal cancer, as due to herbicide exposure is granted. 2. Entitlement to service connection for oral cancer, as due to herbicide exposure is granted. Service connection may be granted for a disability resulting from a disease or injury incurred in or aggravated by active service. See 38 U.S.C. § 1110; 38 C.F.R. § 3.303. A veteran seeking compensation under these provisions must establish three elements: “(1) the existence of a present disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a causal relationship between the present disability and the disease or injury incurred or aggravated during service.” Saunders v. Wilkie, 886 F.3d 1356, 1361 (Fed. Cir. 2018) (quoting Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004)). VA regulations provide that if a veteran was exposed to herbicides during service and meets the requirements for a presumption of herbicide exposure under 38 C.F.R. § 3.307, certain listed diseases are presumptively service connected. 38 U.S.C. § 1116(a)(1); 38 C.F.R. § 3.309(e). The Board notes that VA has conceded the Veteran’s exposure to herbicides, as his service records reflect that he had foreign service in Vietnam. However, only certain listed medical conditions may be granted service connection on a presumptive basis due to exposure to a tactical herbicide. 38 C.F.R. § 3.309(e). Although rectal cancer and oral cancer are not among the diseases afforded a presumption of service connection, the availability of presumptive service connection does not preclude a grant of service connection on a direct basis with proof of causation. See Combee v. Brown, 34 F.3d 1039, 1043-44 (Fed. Cir. 1994); 38 C.F.R. § 3.303. In a January 2020 independent medical opinion, Dr. C. K. opined that, following his review of the Veteran’s medical records and medical literature, the Veteran’s oral and rectal cancer were at least as likely as not related to his herbicide exposure in service. Medical records reflected the Veteran’s extensive history of malignancy. He was diagnosed with oral cancer in 2002 and underwent multiple excisions and experimental therapies for treatment. Human papilloma virus (HPV) was indicated as a possible etiology of the Veteran’s oral cancer. Dr. C. K. explained that there was increasing evidence indicating that some cancers of the oral cavity and oropharynx can have a viral (HPV) etiology consistent with the mechanistic hypothesis explaining an excess of these cancers in Vietnam veterans: immune alterations associated with Agent Orange exposure may have increased susceptibility to HPV infection in the oral cavity and tonsils of Vietnam veterans, thereby making them more prone to the development of squamous-cell carcinomas in these tissues. Dr. C. K. also noted that a chemical in Agent Orange, TCDD, may increase the incidence or progression of human cancers through an interplay of multiple cellular factors. He pointed to studies in laboratory animals where an increase in neoplasms, most notably of the liver, lungs, tyroid, and oral mucosa was seen following TCDD exposure. For these reasons, Dr. C. K. found it was at least as likely as not that the Veteran’s oral cancer was related to Agent Orange exposure, as it increased his risk for the development of oral cancer due to his increased susceptibility to HPV infection. With regard to rectal cancer, Dr. C. K. explained there was similar evidence linking HPV to rectal cancer, which the Veteran was diagnosed with in 2010 and treated with a combination of surgery, chemotherapy, and radiation. Dr. C. K. pointed to a study that found quantitative evidence for the association between HPV and colorectal cancer risk. Therefore, Dr. C. K. opined that the Veteran’s rectal cancer was at least as likely as not related to Agent Orange exposure, as it increased his risk for the development of rectal cancer due to his increased susceptibility to HPV infection. Based on the above, the probative evidence of record is in support of the Veteran’s claims; and as the record does not contain any evidence to the contrary, resolving all reasonable doubt in favor of the Veteran, the Board finds that service connection for oral cancer and rectal cancer as due to exposure to herbicides is warranted and the claims are granted. Gilbert v. Derwinski, 1 Vet. App. 49, 54-56 (1990); 38 U.S.C. § 5107 and 38 C.F.R. § 3.102. 3. Entitlement to service connection for peripheral neuropathy of the left upper extremity, secondary to chemotherapy treatment is granted. 4. Entitlement to service connection for peripheral neuropathy of the right upper extremity, secondary to chemotherapy treatment is granted. 5. Entitlement to service connection for peripheral neuropathy of the left lower extremity, secondary to chemotherapy treatment is granted. 6. Entitlement to service connection for peripheral neuropathy of the right lower extremity, secondary to chemotherapy treatment is granted. Service connection may be established on a secondary basis for a disability which is proximately due to or the result of service-connected disease or injury. 38 U.S.C. § 1131; 38 C.F.R. § 3.310(a). Establishing service connection on a secondary basis requires evidence sufficient to show (1) that a current disability exists and (2) that the current disability was either (a) proximately caused by or (b) proximately aggravated by a service-connected disability. Allen v. Brown, 7 Vet. App. 439, 448 (1995) (en banc). In order to prevail on the issue of secondary service connection, the record must show: (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. See Wallin v. West, 11 Vet. App. 509, 512 (1998); see also Allen, supra. In the January 2020 independent medical opinion, Dr. C. K. opined that the Veteran’s bilateral upper and lower extremity peripheral neuropathy was at least as likely as not due to his chemotherapy treatment. Dr. C. K. indicated that oncology notes attributed the Veteran’s peripheral neuropathy to his oxaliplatin chemotherapy treatment for rectal cancer. Dr. C. K. explained that oxaliplatin was a third-generation platinum compound and was the backbone treatment of colorectal cancer. Peer reviewed medical literature indicated that neuropathic pain-like symptoms during and immediately following the first treatment in 65 to 98 percent of patients predisposed this group to increasingly severe neuropathy in the subsequent cycles. Symptoms were noted to generally persist between cycles and increase in intensity with cumulative dose. Impaired sensation, sensory ataxia, and/or deficit in fine sensory-motor coordination could ultimately occur, with symptoms severe enough to limit patients from performing their activities of daily living. Taking this evidence into consideration, in addition to the lack of any other explanation for the Veteran’s neuropathy (such as diabetes), Dr. C. K. determined that the Veteran’s peripheral neuropathy was at least as likely as not due to his previous chemotherapy treatment. (Continued on the next page)   As there is a medical opinion of record that attributes the Veteran’s peripheral neuropathy to chemotherapy treatment related his service-connected rectal cancer, the Board finds that service connection for peripheral neuropathy of the bilateral upper and bilateral lower extremities on a secondary basis is warranted and the claims are granted. Gilbert v. Derwinski, 1 Vet. App. 49, 54-56 (1990); 38 U.S.C. § 5107 and 38 C.F.R. § 3.102. KRISTI L. GUNN Veterans Law Judge Board of Veterans’ Appeals Attorney for the Board L. Silverblatt, Counsel The Board’s decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.