Citation Nr: 1324050 Decision Date: 07/29/13 Archive Date: 08/07/13 DOCKET NO. 05-09 022 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in St. Petersburg, Florida THE ISSUE Entitlement to service connection for chronic myeloid leukemia (CML), claimed as secondary to herbicide exposure. REPRESENTATION Appellant represented by: Mr. Daniel G. Krasnegor, Attorney at Law WITNESS AT HEARING ON APPEAL The Veteran ATTORNEY FOR THE BOARD J. Murray, Associate Counsel INTRODUCTION The Veteran served on active duty in the United States Navy from June 1964 to June 1966. Service in the Republic of Vietnam is indicated by the record. This matter comes before the Board of Veterans' Appeals (Board) on appeal from a January 2004 rating decision of the Department of Veterans Affairs (VA) Regional Office (RO) in Philadelphia, Pennsylvania, which denied the Veteran's claim. During the course of the appeal, the Veteran moved to Florida, and the jurisdiction now resides with the St. Petersburg, Florida RO. In October 2006, the Veteran presented sworn testimony during a personal hearing in Washington D.C., which was chaired by the undersigned. The Veteran was provided an opportunity to set forth his contentions at the hearing. The record reflects that at this hearing the undersigned set forth the issues to be discussed at the hearing, focused on the elements necessary to substantiate the claims, and sought to identify any further development that was required to help substantiate the claims. These actions satisfied the duties a Veterans Law Judge has to explain fully the issue and to suggest the submission of evidence that may have been overlooked. See Bryant v. Shinseki, 23 Vet. App. 488, 492 (2010) (holding that the requirements of 38 C.F.R. § 3.103(c)(2) apply to a hearing before the Board). A copy of the hearing transcript has been associated with the claims folder. In a July 2008 decision, the Board denied the Veteran's claim of entitlement to service connection for chronic myeloid leukemia. The Veteran appealed that decision to the United States Court of Appeals for Veterans Claims (the Court). In January 2009, the Court vacated the Board's July 2008 decision and remanded the issue to the Board for further consideration pursuant to a Joint Motion for Remand dated earlier in January 2009. In September 2009, August 2010 and December 2011, the Board remanded the claim for further evidentiary development. Additionally, in December 2012, the Board requested an advisory medical opinion from the Veterans Health Administration (VHA) in the matter of this claim. A VHA advisory opinion report was received in January 2013. In a letter dated in February 2013, the Board wrote to the Veteran and notified him of the receipt of the VHA opinion and return of the case to the Board for further appellate proceedings. In response, the Veteran's representative submitted additional arguments in support of claim, including assertions against the adequacy of the VHA opinion. The Veteran has not submitted any additional evidence for initial consideration. See 38 C.F.R. § 20.1304 (2012). The case is now ready for appellate review. A review of the Virtual VA paperless claims processing system does not reveal any additional documents pertinent to the present appeal. FINDINGS OF FACT 1. The Veteran had service in the Republic of Vietnam during the Vietnam War era, and his exposure to herbicides, including Agent Orange, is presumed. 2. The Veteran has not been diagnosed with a B-cell leukemia, to include chronic lymphocytic leukemia or hairy-cell leukemia. 3. The Veteran's chronic myeloid leukemia (CML) did not manifest during service or within his post-service year, and the preponderance of the evidence is against a finding that a relationship exists between the Veteran's currently diagnosed CML and his military service, to include his presumed exposure to herbicides in Vietnam. CONCLUSION OF LAW The criteria for service connection for chronic myeloid leukemia (CML) are not met. 38 U.S.C.A. §§ 1101, 1110, 1112, 1113, 1137 (West 2002 & Supp. 2011); 38 C.F.R. §§ 3.303, 3.307, 3.309 (2012). REASONS AND BASES FOR FINDINGS AND CONCLUSION 1. Stegall Concerns As noted in the Introduction, the Board remanded the Veteran's service-connection claim in September 2009, August 2010 and December 2011 for additional development and readjudication. The Board finds that substantial compliance with its prior remand instructions has been achieved, and that Board adjudication on the merits of this issue is now appropriate. In its September 2009 remand, the Board instructed the RO to send the Veteran corrective notice complying with the requirements of the Veterans Claims Assistance Act of 2000 (VCAA); obtain a copy of a bone marrow report from Armed Forces Institute of Pathology (AFIP); to provide the Veteran with a VA examination to determine the etiology of his claimed disorder; and then readjudicate the claim based on the additional evidence. The record shows that a November 2009 notice letter was sent and a June 2002 AFIP report has been associated with the claims folder. The Veteran underwent a VA examination in March 2010. The Veteran's claim was readjudicated in an April 2010 supplemental statement of the case (SSOC). After the issuance of the April 2010 SSOC, the Veteran submitted additional medical articles in support of his claim without a waiver of initial consideration, and the Board remanded the matter again in August 2010. The Veteran was provided with a September 2011 SSOC, in which the additional evidence was considered. When the matters returned, the Board found that an addendum opinion was needed to address the inadequacy of the March 2010 VA examination report. A June 2012 addendum to the March 2010 VA examination report has been associated with the claims folder and the claim was readjudicated in a July 2012 SSOC. Additionally, in December 2012, the Board solicited an expert medical opinion from a physician with the Veterans Health Administration (VHA) concerning the nature and etiology of the Veteran's claimed disorder. In January 2013, the Board received the requested VHA opinion. The Veteran submitted additional argument in response to this medical opinion in an April 2013 brief, which has been associated with the claims folder. The Board finds that it's September 2009, March 2010, and December 2011 remand instructions have been fully complied with. See Stegall v. West, 11 Vet. App. 268, 271 (1998) [where the remand orders of the Board are not complied with, the Board errs as a matter of law when it fails to ensure compliance]. 2. VA's Duty to Notify and Assist The Veterans Claims Assistance Act of 2000 (VCAA), codified in pertinent part at 38 U.S.C.A. §§ 5103, 5103A, and the pertinent implementing regulation, codified at 38 C.F.R. § 3.159, provide that VA will assist a claimant in obtaining evidence necessary to substantiate a claim but is not required to provide assistance to a claimant if there is no reasonable possibility that such assistance would aid in substantiating the claim. They also require VA to notify the claimant and the claimant's representative, if any, of any information, and any medical or lay evidence, not previously provided to the Secretary that is necessary to substantiate the claim. As part of the notice, VA is to specifically inform the claimant and the claimant's representative, if any, of which portion, if any, of the evidence is to be provided by the claimant and which part, if any, VA will attempt to obtain on behalf of the claimant. Although the regulation previously required VA to request that the claimant provide any evidence in the claimant's possession that pertains to the claim, the regulation has been amended to eliminate that requirement for claims pending before VA on or after May 30, 2008. The Board also notes that the United States Court of Appeals for Veterans Claims (Court) has held that the plain language of 38 U.S.C.A. § 5103(a) requires that notice to a claimant pursuant to the VCAA be provided "at the time" that, or "immediately after," VA receives a complete or substantially complete application for VA-administered benefits. Pelegrini v. Principi, 18 Vet. App. 112, 119 (2004). The Court further held that VA failed to demonstrate that "lack of such a pre-AOJ-decision notice was not prejudicial to the appellant, see 38 U.S.C. § 7261(b)(2) (as amended by the Veterans Benefits Act of 2002, Pub. L. No. 107-330, § 401, 116 Stat. 2820, 2832 ) (providing that '[i]n making the determinations under [section 7261(a)], the Court shall...take due account of the rule of prejudicial error')." The timing requirement enunciated in Pelegrini applies equally to the initial-disability-rating and effective-date elements of a service-connection claim. Dingess v. Nicholson, 19 Vet. App. 473 (2006). The record reflects that the Veteran was provided all required notice by correspondence dated in September 2008, and November 2009. Although the Veteran was not provided complete notice until after the initial adjudication of the claim, the Board finds that there is no prejudice to him in proceeding with the issuance of a final decision. See Bernard v. Brown, 4 Vet. App. 384, 394 (1993). In this regard, the Board notes that following the provision of the required notice and the completion of all indicated development of the record, the originating agency readjudicated the Veteran's claim. There is no indication in the record or reason to believe that the ultimate decision of the originating agency on the merits of the claim would have been different had complete VCAA notice been provided at an earlier time. See Overton v. Nicholson, 20 Vet. App. 427, 437 (2006) (A timing error may be cured by a new VCAA notification followed by a readjudication of the claim). Regarding VA's duty to assist, all appropriate development to obtain the Veteran's pertinent medical records, including service treatment records and VA and private treatment records, has been completed. The Veteran has not identified any pertinent, outstanding records that could be obtained to substantiate his claim, including any records of post-service treatment. The Board is also unaware of any such records. The Board notes that the Veteran is in receipt of disability benefits from the Social Security Administration (SSA), and records related to these benefits are not of record. In this regard, after being contacted by VA, SSA responded that, after an exhaustive and comprehensive search, these records are not available. As such, VA has fulfilled its duty to assist the Veteran in obtaining necessary evidence. See 38 U.S.C.A. § 5103A(d); see also 38 C.F.R. § 3.159 (c)(4) (2007); Wells v. Principi, 327 F. 3d 1339, 1341 (Fed. Cir. 2002). Moreover, the Veteran has been afforded appropriate VA examination in March 2010 with a VA addendum medical opinion dated in June 2012. Additionally, the Board obtained a VHA advisory opinion in January 2013 that considered all the previous medical statements as well as discussed relevant medical literature. The report demonstrates that the medical examiner reviewed the evidence of record and rendered an appropriate opinion based on the question presented by the Board. This opinion was rendered after a thorough review of the claims file and is supported by the evidence of record. Despite the representative's April 2013 argument to the contrary, the Board finds that this medical opinion adequately addresses the relevant information and includes well-supported opinions. Therefore, the Board finds that the evidence of record is adequate for rating purposes. See Barr v. Nicholson, 21 Vet. App. 303, 311 [affirming that a medical opinion is adequate if it provides sufficient detail so that the Board can perform a fully informed evaluation of the claim]. Accordingly, the Board concludes that VA has complied with its duty to assist the Veteran. Parenthetically, the Board notes that the May 2007 examination relied upon by the Board in its now-vacated 2009 decision will not be addressed as it has been deemed inadequate by the parties to the aforementioned joint motion. In short, the Board has carefully considered the provisions of the VCAA, in light of the record on appeal and, for the reasons expressed above, finds that the development of the Veteran's claims has been consistent with said provisions. The Board is satisfied that any procedural errors in the originating agency's development and consideration of the issues on appeal were insignificant and nonprejudicial to the Veteran. The Veteran has been accorded ample opportunity to present evidence and argument in support of his claims. See 38 C.F.R. § 3.103. He has retained the services of a representative, and he has had an opportunity to testify at a personal hearing before the undersigned Veterans Law Judge. 3. Service Connection Service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by service. 38 U.S.C.A. §§ 1110, 1131; 38 C.F.R. § 3.303(a). Service connection may also be granted for any disease diagnosed after discharge when all of the evidence establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d). 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. If a condition noted during service is not shown to be chronic, then generally, a showing of continuity of symptoms after service is required for service connection. See 38 C.F.R. § 3.303(b). The chronicity provision of 38 U.S.C.A. § 3.303(b) is applicable 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 such condition. Regulations also provide that service connection may be granted for a disability diagnosed after discharge, when all the evidence, including that pertinent to service, establishes that the disability is due to disease or injury which was incurred in or aggravated by service. 38 C.F.R. § 3.303(d). Certain chronic diseases, including leukemia, although not shown in service, may be presumed to have incurred in or aggravated by service if they become manifested to a compensable degree within one year of separation from active duty. 38 U.S.C.A. §§ 1101, 1112, 1113; 38 C.F.R. §§ 3.307, 3.309. To prevail on the issue of service connection, 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. See Hickson v. West, 12 Vet. App. 247, 253 (1999). A veteran who served in the Republic of Vietnam during the Vietnam era is presumed to have been exposed to certain herbicide agents (e.g., Agent Orange). 38 U.S.C.A. § 1116(f); 38 C.F.R. § 3.307(a)(6)(iii). A veteran must actually set foot within the land borders of Vietnam, to include the contiguous waterways, in order to be entitled to the statutory presumptions for disabilities claimed as a result of exposure to herbicides. See Haas v. Peake, 525 F.3d 1168 (Fed. Cir. 2008); see also VAOPGCPREC 27-97. When such a veteran contracts a disease associated with exposure to herbicides (listed in 38 C.F.R. § 3.309(e)) that becomes manifest to a compensable degree within the time period specified in 38 C.F.R. § 3.307(a)(6)(ii), the disease will be considered to have been incurred in service, even though there is no evidence of such a disease during the period of service. These conditions include: chloracne or other acneform diseases consistent with chloracne, Type 2 diabetes, Hodgkin's disease, ischemic heart disease, all chronic B-cell leukemias (including, but not limited to, hairy-cell leukemia and chronic lymphocytic leukemia), multiple myeloma, non-Hodgkin's lymphoma, Parkinson's disease, acute and subacute peripheral neuropathy, porphyria cutanea tarda, prostate cancer, respiratory cancers (cancer of the lung, bronchus, larynx, or trachea) and soft-tissue sarcomas (other than osteosarcoma, chondrosarcoma, Kaposi's sarcoma, or mesothelioma). 38 C.F.R. § 3.309(e). VA has determined that there is no positive association between exposure to herbicides and any other condition for which it has not specifically determined that a presumption of service connection is warranted. See Notice, 59 Fed. Reg. 341-46 (1994); see also 61 Fed. Reg. 57,586-57,589 (1996); 72 Fed. Reg. 32,345 -32,407 (Jun. 12, 2007). Notwithstanding the foregoing, the United States Court of Appeals for the Federal Circuit has determined that the Veterans' Dioxin and Radiation Exposure Compensation Standards (Radiation Compensation) Act, Pub. L. No. 98-542, § 5, 98 Stat. 2724, 2727- 29 (1984), does not preclude a veteran from establishing service connection with proof of actual direct causation. Combee v. Brown, 34 F.3d 1039(Fed.Cir. 1994). The Court has specifically held that the provisions of Combee are applicable in cases involving herbicide exposure. McCartt v. West, 12 Vet. App. 164, 167(1999). The determination as to whether the requirements for service connection are met is based on an analysis of all the evidence of record and the evaluation of its credibility and probative value. 38 U.S.C.A. § 7104(a); Baldwin v. West, 13 Vet. App. 1 (1999); 38 C.F.R. § 3.303(a). If there is at least an approximate balance of positive and negative evidence regarding any issue material to the claim, the claimant shall be given the benefit of the doubt in resolving each such issue. 38 U.S.C.A. § 5107; Ortiz v. Principi, 274 F.3d 1361, 1364 (Fed. Cir. 2001); 38 C.F.R. §§ 3.102. On the other hand, if the Board determines that the preponderance of the evidence is against the claim, it has necessarily found that the evidence is not in approximate balance, and the benefit of the doubt rule is not applicable. Ortiz, 274 F.3d at 1365. Presumptive Basis for Service Connection In this case, the Veteran's DD Form 214 and available personnel records indicate that he had service in Vietnam during the Vietnam era; therefore, exposure to herbicides is presumed. Nonetheless, service connection for chronic myeloid leukemia (CML) on a presumptive basis is not available because this condition is not one which may be presumed to be caused by herbicide exposure under VA regulations. Specifically, CML is a disease process not included in the category of chronic B-cell leukemias listed in 38 C.F.R. § 3.309(e). See 75 Fed. Reg. 53202 (August 10, 2010). The Board is cognizant that the lay and medical evidence that reflects the Veteran was informed that he was diagnosed with both CML and non-Hodgkin's lymphoma based on the findings from a May 2002 bone marrow biopsy and aspiration study pathology study. See An April 2004 statement from the Veteran's treating VA oncologist. In the April 2004 letter from the Veteran's VA oncologist, he noted a May 2002 bone marrow biopsy indicating the presence of a cell which could represent non-Hodgkin's lymphoma, a disease process that is presumptively service-connected based on Agent Orange exposure. However, the subsequent obtained report of a June 2002 Armed Forces Institute of Pathology of the findings from the bone marrow biopsy and aspiration study contains an impression of CML, only. The staff pathologist concluded that the histologic findings were consistent with clinical history of CML. The January 2013 VHA medical advisor confirmed that a review of the reports from an April 2001 and the May 2002 bone marrow studies confirmed a diagnosis of CML, and did not reveal evidence of other leukemic diagnosis. See the January 2013 VHA medical advisor opinion report. There is no diagnostic evidence of record that confirms a diagnosis of non-Hodgkin's lymphoma. In light of the foregoing, the Board concludes that the weight of the evidence is against a finding that the Veteran currently has, or has had at any time during the course of this appeal, a leukemic disorder other than CML. As the weight of the probative evidence shows that the Veteran has CML rather than non-Hodgkin's lymphoma, and VA regulations do not provide for the award of service connection for CML on a presumptive based on in-service herbicide exposure, service connection on a presumptive basis is not warranted. See 38 C.F.R. § §3.307, 3.309(e). Direct Basis for Service Connection Notwithstanding the inapplicability of the regulations pertaining to presumptive service connection, the Board is obligated to fully consider the Veteran's claim on a direct basis. See Combee, 34 F.3d at 1039. As noted above, in order to establish service connection for the claimed disorder, there must be (1) evidence of a current disability; (2) evidence of in-service incurrence or aggravation of a disease or injury; and (3) evidence of a nexus between the claimed in-service disease or injury and the current disability. See Hickson, 12 Vet. App. at 253. It is undisputed that the Veteran currently has CML. Accordingly, Hickson element (1) is satisfied. With respect to Hickson element (2), the Board will separately address in-service disease and injury. Concerning in-service disease, the Veteran does not contend that he developed CML during service or within the one year presumptive period found in 38 C.F.R. § 3.309(a). Rather, the private treatment records indicate that his condition was diagnosed in October 1998 on a physical examination involving blood work, with positive Philadelphia chromosome diagnosed in April 1998. This diagnosis comes more than three decades after the Veteran's separation from service in 1966. The basis of the Veteran's claim is that his condition results from his exposure to Agent Orange and benezene exposure during his period of service. Again, the Veteran's exposure to herbicides, including Agent Orange, is presumed. The Veteran also reports that he was exposed to benezene contained in kerosene fuel while he was stationed in Okinawa. He reports during his deployment he lived in a hut which was heated by a kerosene portable heater and he was exposed to the fumes regularly. He also reports direct contact with kerosene when he used kerosene to clean his arms and hands after working with roofing tar and creosote timber construction. The Board has no reason to doubt the credibility of the Veteran's reported exposure to kerosene. Therefore, the second Hickson element has arguably been met with respect to in-service injury due to exposure to herbicides and benzene. With respect to crucial Hickson element (3), nexus or relationship, between the Veteran's diagnosed CML and his herbicides and benzene exposure during service. As this question is essentially medical in nature, the Board is prohibited from exercising its own independent judgment to resolve medical questions. See Colvin v. Derwinski, 1 Vet. App. 171, 175 (1991). The Veteran has submitted medical literature and articles from various sources and websites on the subjects of Agent Orange, cancer, dioxin, benzene, toxic substances and leukemia. In addition, the Veteran has submitted several private medical statements in support of his claim. The record also contains the reports of VA medical opinion and VHA medical advisory opinion that weigh against the Veteran's claims. A June 2005 letter from S. C. G. M.D., PhD, reflects that he had known the Veteran since 1998 and that he is concerned about his leukemia. Dr. G. noted that leukemia is a type of sarcoma that responds to a drug called Gleevac. He then noted that sarcomas and many types of leukemias are associated with Agent Orange exposure. Considering that the Veteran's leukemia is now controlled by Gleevac, the doctor opined that one could likely blame Agent Orange for the leukemia. Dr. G. stated that he had spoken to several physicians and they agree that Agent Orange is a likely culprit in causing the Veteran's leukemia. In a June 2005 written statement from another treating physician, C. I. J. M.D., he noted that since Agent Orange contains the well-known carcinogen dioxin, it is reasonable that his relatively rare cancer is at least in some part related to dioxin exposure. Dr. J. observed that Agent Orange had been linked to soft tissue sarcomas. He also noted links to acute myelogenous leukemia in childhood, including the children of veterans. Dr. J. felt it was reasonable to suspect a link between the Veteran's CML and his exposure, and he felt that future epidemiological studies would demonstrate this in all likelihood. Dr. G. submitted an additional letter in support of the Veteran in August 2009. He stated that many blood disorders, especially CML are multi-lineage disorders and symptoms in each patient can be different but most have red cell, granulocyte and platelet disorders. Dr. G. remained concerned that the Veteran's blood disorder is a complication of Agent Orange. Dr. G. attached relevant literature on benzene, dioxin, Agent Orange, and Veterans Health from the National Academies of Science and the Agency for Toxic Substances and Disease Registry. The Veteran underwent a VA examination for hemic disorders in March 2010 by a VA physician who reviewed the claims folder and examined the Veteran. It was noted that the Veteran was still on Gleevac for his CML. The diagnosis was CML, noted to be in remission. There was no evidence of non-Hodgkins lymphoma (NHL). The March 2010 VA examiner noted that the CML was not manifested in service and was not related to Agent Orange exposure. He explained that multiple studies have been done and CML is not an associated condition. The VA examiner added that Agent Orange was studied in totality including all its chemical agents. In December 2011, the Board found that the March 2010 examination report did not fully address all of the questions posed in the Board's remand, nor did it phrase the answer using the proper standard of review. An addendum report was prepared in June 2012 by a VA physician's assistant who noted that the case and the opinion rendered were discussed with the VA physician who was the CMO (chief medical officer) of the Bay Pines VA medical center. The report reflects that the Veteran has CML, initially diagnosed in 1998. In the June 2012 addendum report, the VA examiner explained that the Veteran's CML is less likely than not related to events that occurred in service or within one year of separation from service. The June 2012 VA examiner noted that the Veteran was noted to have been diagnosed 32 years after separation. The examiner further noted that although dioxin is a known carcinogen it is not associated with the development of CML. The letters written by Dr. J. and Dr. G. were reviewed and the June 2012VA examiner stated that attributing Agent Orange exposure as an etiologic factor is not supported in medical literature nor have government studies revealed an association. In the addendum report, the VA examiner also indicated that the Veteran's CML is not secondary to benzene, and continued that benzene is known to cause certain cancers but is not associated with CML. The only accepted risk factor for CML is ionizing radiation exposure. The 2006 study from the Mount Sinai Medical Center linking CML to benzene was reviewed and noted to be not supported by current medical literature and standards. The June 2012 VA examiner concluded by stating that it is medically accepted that CML is not caused by benzene exposure. The Veteran submitted another medical statement from a hematologist-oncologist, Dr. W. W. M. L., dated in October 2012. Dr. M. L. reviewed the medical records associated with the claim and stated the following: "It is nearly impossible to provide definitive evidence proving that there is no association between [the Veteran's] military service and his illness. On the other hand, there is certainly a potential causative association between the totality of Agent Orange exposure and his CML disease. Therefore, I feel that one can come to the opinion that it is as likely as not that his Chronic Myeloid Leukemia is secondary to herbicide exposure." The Board obtained a VHA medical advisory opinion in January 2013. The VHA medical advisor noted that he reviewed the Veteran's claims file, to include the medical treatise evidence of record, the opinion of Dr. M.L., as well as outside medical literature and research. The VHA medical advisor noted that there has been no evidence linking CML to Agent Orange exposure, despite ample epidemiological data, and he concluded that it was not likely that the Veteran's CML is linked to his presumed herbicide exposure. The VHA medical advisor also noted that Dr. M. L., in his October 2012 medical statement, admitted that "there was no causal link between chronic myeloid leukemia and herbicide exposure." With regard to the Veteran's reported exposure to benezene, the VHA medical advisor concluded that it was also not likely that the Veteran's CML is related to his in-service benezene exposure. The VHA medical advisor noted that the medical literature submitted by the Veteran did not demonstrate a causal relationship. Rather, the articles only noted that the overall risk was non-significantly elevated. Based on a review of the foregoing medical, the Board finds that the preponderance of the evidence is against the finding of a medical nexus between the Veteran's CML and his military service, including herbicide and benzene exposures. The January 2013 VHA medical advisory opinion in combination with the June 2012 VA medical opinion are afforded considerable weight in the determination that the Veteran's current CML is not related to in-service to exposure to herbicides and benzene. Both of these opinions were based on a review of the Veteran's claims files and the specific evidence outlined by the Board as being potentially favorable to the claim. In the combined reports, the VA examiners summarized the Veteran's relevant in-service and post-service medical history, to include Agent Orange and benzene exposures in service and diagnosis of CML in 1998. When viewed in this context, the January 2013 VHA medical expert's opinion and June 2012 VA examiner's opinions are accompanied by a sufficient explanation. Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008); see also Wray v. Brown, 7 Vet. App. 488, 493 (1995) (holding that the adoption of an expert medical opinion may satisfy the Board's statutory requirement of an adequate statement of reasons and bases if the expert fairly considered the material evidence seemingly supporting a veteran's position); Lee v. Brown, 10 Vet. App. 336, 338 (1997) (an etiological opinion should be viewed in its full context, and not characterized solely by the medical professional's choice of words). The Board finds these opinions to be highly credible and probative of the issue of nexus, or the lack thereof. While the Board has considered the other medical opinions of record, it finds them less probative as to the issue of the etiology of the Veteran's CML. The private opinions of Drs. G. and J. were addressed in the June 2012 VA examiner's medical opinion and the private opinion of Dr. M. L. was discussed in the January 2013 VHA expert's medical opinion. The Board is satisfied that these private opinions do not establish a link between the CML and service in light of the 2012 and 2013 VA opinions. Medical opinions expressed in speculative language do not provide the degree of certainty required for medical nexus evidence. Stegman v. Derwinski, 3 Vet. App. 228, 230 (1992); Bostain v. West, 11 Vet. App. 124, 127-28 (1998). The opinions of Dr. G. ("one could likely blame Agent Orange for the leukemia"[emphasis added]), Dr. J. ("it is thus reasonable to suspect a linkage to his [CML]" [emphasis added]), and Dr. M. L. ("certainly a potential causative association between the totality of Agent Orange exposure and his CML disease" [emphasis added]) are all couched in language too speculative to be probative. Both the 2013 and 2012 VA opinions definitively explained that it is medically accepted that CML is not caused by benzene or herbicide exposure. Thus, the other medical evidence is considered to have lesser probative value as to establishing a nexus between current disability and service. VA must consider all favorable lay evidence of record. 38 USCA § 5107(b); Caluza v. Brown, 7 Vet. App. 498 (1995). Accordingly, in addition to the medical evidence above the Board has considered the lay evidence of record in the form of the Veteran's correspondence to VA and his testimony. In this regard, the Board notes the Veteran's own statements which suggest that his leukemia is associated with herbicide exposure. While the Veteran is competent to describe his symptoms, as a layperson he is not competent to determine the cause of his leukemia. The Board must stress that this type of etiology opinion, as opposed to an opinion predicated on continuity-of-symptomatology since service or symptoms capable of lay observation, is not competent evidence in the absence of medical training or credentials. See 38 C.F.R. § 3.159(a)(2); see also Routen v. Brown, 10 Vet. App. 183, 186 (1997) ("a layperson is generally not capable of opining on matters requiring medical knowledge"). Regarding the medical treatise evidence referenced by the Veteran throughout the course of this appeal, the Court has held that a medical article or treatise, "can provide important support when combined with an opinion of a medical professional," if the medical article or treatise evidence discussed generic relationships with a degree of certainty such that, under the facts of a specific case, there is at least "plausible causality" based upon objective facts rather than on an unsubstantiated lay medical opinion. Sacks v. West, 11 Vet. App. 314 (1998). The medical treatise, [textbook, or article] must provide more than speculative, generic statements not relevant to the appellant's claim but must discuss generic relationships with a degree of certainty for the facts of a specific case. Wallin v. West, 11 Vet. App. 509, 514 (1998). In this case, the articles do not provide statements for the facts of the Veteran's specific case. Moreover, the literature is discussed in detail in the June 2012 report and the theories asserted were noted to be not currently medically accepted. For these reasons, the Board finds that the articles do not contain the specificity to constitute competent evidence of the claimed medical nexus. See Sacks, 11 Vet. App. at 317; see also Libertine v. Brown, 9 Vet. App. 521, 523 (1996). In summary, CML did not begin in service or within one year of separation. It is not shown by competent evidence to be causally related to service, to include as secondary to herbicide exposure, and service connection may not be presumed. Thus, the criteria for service connection for CML are not met, and the claim is denied. In reaching this decision, the Board has considered the benefit of the doubt doctrine but has determined that it is not applicable to these claims because the preponderance of the evidence is against the claim. ORDER Entitlement to service connection for chronic myeloid leukemia (CML) is denied. ____________________________________________ DAVID L. WIGHT Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs