Zhirui et al. (2018) describes the case of a 37-year-old trans women who is BRCA2-positive, has already undergone genital surgery, and has since been taking daily estradiol for several years. Notably, as male-assigned people with BRCA mutations are at an increased risk of prostate cancer and reassignment surgery does not remove the prostate, regular screening for prostate cancer was recommended:
Given the fact that she had undergone transgender surgery including bilateral orchiectomy with ongoing hormonal supplementation, her cancer risks were difficult to estimate. However, she was counseled regarding the risks of breast and prostate cancer. Chemoprevention with anti‐estrogen agents for breast cancer was also discussed, but she was not a good candidate given her ongoing estrogen supplementation. Subsequent referrals were made to general surgery and urology to further discuss her breast and prostate cancer risks, respectively. …
Screening for prostate cancer is recommended for men who are carriers of BRCA mutation. The serum PSA levels that trigger a diagnostic prostate biopsy in this patient population are currently set at 3 ng/mL. We do believe, however, that in the case of a transgender BRCA mutation carrier who is already castrated and has undetectable levels of PSA, any change in DRE or detectable PSA levels should trigger a diagnostic prostate biopsy.
In this case, the patient chose to undergo prophylactic mastectomy and reconstruction:
Her breast cancer risk, however, is increased due to her requirement for hormonal replacement. She decided to proceed with bilateral prophylactic nipple sparing mastectomies with immediate reconstruction using deep inferior epigastric artery perforator (DIEP) flap in 2016. Pathology revealed no evidence of malignancy.
An earlier publication (Corman et al., 2016) reports on the case of a trans woman with a BRCA2 mutation who developed breast cancer after 7 years of hormone therapy, with recurrence 30 months after right mastectomy. The authors offered the following treatment and screening recommendations for trans women with BRCA mutations:
A BRCA2 mutation complicates management and follow-up in MtF TG persons. In those who have a BRCA2 mutation diagnosed before initiation of hormonal therapy, cancer risks and alternatives to hormonal therapy (e.g., prosthetic breast augmentation) should be discussed. Male BRCA2 mutation carriers should undergo surveillance that includes regular self and clinical breast examination, but in men, imaging studies and prophylactic mastectomy are not part of guideline recommendations (National Comprehensive Cancer Network 2016). In BRCA2-positive MtF cases that have hormone-induced breast formation, it would seem prudent to adopt yearly screening mammography and/ or MRI, as would be the case in adult genetic females (Balmaña et al. 2011, National Comprehensive Cancer Network 2016). BRCA2-positive patients have higher risks for prostate cancer. As complications of prostatectomy can be significant, removal of the prostate is generally not part of the sex reassignment surgery of MtF patients (Hembree et al. 2009). Prostate examinations should be performed at least once a year along with prostatespecific antigen measurement. During follow-up, the risk of other potential BRCA2-associated cancers should be kept in mind.
Overall, trans women on hormone therapy are not at any greater risk of breast cancer than cis women (Joint et al., 2018). However, for those with an elevated risk of cancer due to these mutations, regular screening and surveillance is essential. ■