General approach to cancer screening among transgender persons

We know from the medical literature that there is ‘no solid evidence on whether or not there is an increased risk for trans persons with hormonal treatment to develop cancer more than any other control group’. However, this misconception persists. Existing studies are rather small and must of course be approached with caution. Oncological data in trans men and nonbinary people assigned female at birth are limited to few case reports, recently summarized: one vaginal, one cervical, 7 breast, 3 ovarian, and one endometrial cancers have been described to date. The prevalence of hormone sensitive cancers seems to be low among trans women and nonbinary people assigned male at birth during hormonal treatment (Braun et al, 2017).

When screening for cancer, it is important to conduct exams and tests based on which organs or body parts the person has. As a general rule, we can say that if an individual has a specific body part or organ and meets the criteria for screening based on risk factors or symptoms, this screening must be done, regardless of whether the person is using hormones. We will discuss a few specific hormonal cancers here.

Breast cancer

Breast cancer has been recorded in transgender women, but this relates to very low numbers. We know from extensive research that the risk of breast cancer for trans women or nonbinary persons taking oestrogen hormone treatments is just as low as if the person was not taking hormone treatments, similar to the risk of cisgender men. So far, medical literature has been very reassuring, concluding that the risk of developing breast cancer may be lower than that in the non-transgender female population. Breast cancer screening for trans women or nonbinary persons taking oestrogen hormone treatments is best to still be carried out just like with other women, following several years of hormonal treatment. A mammography can be used as a screening method.

For trans men and nonbinary people assigned female at birth who have not undergone chest surgery or who only have partial breast removal, the detection measures for cisgender women continue to apply. In general breast screening after mastectomy is not performed, but in theory, rest tissue is possible. In case of worries or complaints, further investigation is recommended, especially in cases where there is a genetic/familial background of breast cancer.

Prostate and testicular cancer

With regards to prostate cancer, there are some known cases of trans women taking hormone therapy being affected. In principle, the anti-androgen treatment and the oestrogen treatment are protective against prostate cancer. It is therefore thought that the prostate cancers described were already present before hormonal treatment started. The doctor examining the patient should always be aware of the potential for prostate cancer in transgender women and nonbinary people assigned male at birth, even if they underwent surgeries. Research by Ghent University Hospital on 50 trans women concluded that there were neither clinical nor ultrasound reasons to suspect prostate pathology.

In literature there is only one known story of a trans woman with testicular cancer. Chances are that androgen suppression reduces the risk of testicular cancer. A routine testicle test is not specifically necessary for transgender women and nonbinary people who have testes and are under hormonal treatment.

Cervix, endometrium, ovarian cancer

Transgender men and nonbinary people assigned female at birth who have a cervix have a risk of developing cervical cancer, regardless of if they are taking testosterone therapy. This is the third most frequent cancer globally. This cancer is usually caused by infection with the human papilloma virus. Having a smear test performed is sometimes a challenge. This can stem from the relationship of the trans person with their body, from frequent hostility/prejudice/lack of knowledge in these settings or from the vagina becoming drier or more fragile and internal exams becoming painful during use of testosterone therapy. A specific understanding and trusting relationship with the doctor is recommended. Getting an HPV vaccination at a young age reduces the risk of developing cervical, oral and anal cancer. Vaccination at an older age has no proven effect. Obtaining a cervical smear can be done through a doctor or gynaecologist or through the Gender Wellbeing Clinic.

Transgender men and nonbinary people assigned female at birth who have not undergone a uterus removal (hysterectomy) have the risk of developing endometrial cancer, but the chance of this is extremely small. There are no specific guidelines for undergoing routine screening. In the case of unexpected vaginal bleeding when under testosterone treatment, a gynaecological check-up should follow, especially if menstruation had previously ceased and bleeding reappears. Some patients with ovarian cancer have also been recorded, but at this point there is no evidence to suggest that trans men or nonbinary people assigned female at birth under testosterone treatment have an increased risk of developing ovarian cancer.

References:

• ​Braun H., Nash R., Tangpricha V., Brockman J., Ward K., & Goodman M. 2016. Cancer in Transgender People: Evidence and Methodological Considerations. Epidemiol Rev 2017; 39: 93–107.