Limiting the number of providers who can order genetic testing helps maintain quality control and ensure a comprehensive database of patient testing. At the Albuquerque VAMC, Dr. Lin is currently the only provider who can order genetic testing for cancer risk assessment. Nearly all GCRA consultations, from obtaining a detailed family history to providing education on the risks, benefits, and limitations of genetic testing, can be conducted via telemedicine. The VA GCRA program in Utah has established a number of telemedicine collaborations with VA facilities around the country, beginning with BRCA consultations and branching out into a national LS screening program.
The first few years of the program have shown some unexpected results, including a much higher referral rate for HBOC referrals than was anticipated. The reasons for this are not clear. The high rate of polyposis referrals can be attributed in large part to the robust CRC screening program in the VA system. Veterans are routinely screened for CRC with occult blood tests, and positive results are referred for colonoscopy. Nearly 400 veterans per year have a colonoscopy at the Albuquerque VAMC.
Because the VA screening program begins at age 50 years, nearly all the veterans referred to date have had their first polyp diagnosed at age ≥ 50 years. Unfortunately, the 1 patient who had polyps and CRC at a young age was not tested due to lack of budget when she was evaluated. By contrast, in a large study, the median age of first polyp diagnosis in patients with APC mutation was 30 years, and with biallelic MUTYH mutations was 47 years. 7
The difficulty in distinguishing which veterans should be tested for attenuated FAP lies in the fact that age of onset and personal or family history alone or in
combination do not seem to be adequate discriminators to screen out low-risk veterans who do not need testing. 7 Considering the number of veterans referred each year and the incidence of attenuated FAP, if every veteran who fit the current criteria of 20 adenomatous polyps lifetime were tested, about 35 to 70 veterans would have to be tested to detect 1 mutation carrier. The development of clinical criteria to identify low-risk patients would be very helpful.
On the other hand, referrals for LS were uncommon. This is consistent with results reported elsewhere. 8 For this reason, diagnosis of LS has shifted from clinical identification to pathologic screening for the molecular hallmarks of LS in tumor specimens. 8,9 Shortly after the GCRA clinic was established, a pathologist with an interest in GI malignancies developed and validated a pathologic screening program using immunohistochemistry (IHC) staining for mismatch repair (MMR) gene expression, with the assistance of a pathologist who had been involved in a community-based LS screening program.9 For the past 3 years, all CRC patients aged ≤ 60 years have been screened for loss of expression of MMR IHC. Patients identified have been seen in the GCRA clinic to discuss possible genetic testing. This screening program is now extending to all patients with CRC aged ≤ 70 years, in line with consensus recommendations. 10