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We present an unusual case of a 46,XX phenotypic male with short stature, low testicular volume, and bilateral gynaecomastia since puberty not attributable to elevated BMI, who was found to carry a pathogenic BRCA2 variant in his early 40s. Karyotype showed 46,XX with no SRY detectable on FISH. No internal or external female organs were present.The literature lacks data on cancer risk in 46,XX males with BRCA2. Through extrapolation of breast cancer risk from cisgender women, cis-men and women with BRCA2, and emerging evidence of breast cancer risk in transgender populations with high-risk cancer susceptibility genes, our multidisciplinary team concluded his breast cancer risk may exceed that of cis-men with BRCA2, and could approach cis-female risk due to longstanding breast tissue. Emerging evidence from transgender populations, for instance trans women on long-term HRT and trans men post-chest surgery provided further insights into possible risks.Very high-risk breast screening was offered to our patient, with the option of risk-reducing mastectomy, which the patient is still considering. This case highlights the limitations of binary risk models and the importance of individualised patient care. Rare presentations require multidisciplinary input, ethical considerations, and patient-centred counselling.