Background: Women with an increased hereditary risk of breast cancer can undergo prophylactic mastectomy (PM), which provides a significant, but not total, risk reduction. There is an ongoing discussion about how much skin and subcutaneous tissue should be resected to perform an adequate PM while leaving viable skin flaps.
Methods: Forty-five women who had undergone PM were examined with magnetic resonance tomography (MRT), ultrasound (US) and clinical examination (CE) by a plastic surgeon and a general surgeon to estimate skin flap thickness.
Results: The estimated mean skin flap thickness after PM was 13.3 (± 9.6), 7.0 (± 3.3), 6.9 (± 2.8) and 7.4 (± 2.8) mm following MRT, US, and CE performed by a plastic surgeon and a general surgeon, respectively. The mean difference in estimated skin flap thickness was significant between MRT and the other measuring methods, while there was no significant difference between US and CE, nor between CE performed by the surgeons. The mean skin flap thickness was significantly affected by the age at PM. Following PM, necrosis was detected in 7/23 (30.4%) of the breasts in skin flaps ≤ 5 mm and in 5/46 (10.9%) of the breasts in skin flaps > 5 mm (OR 6.29; CI 1.20–32.94; p = 0.03).
Conclusion: The odds of getting postoperative necrosis was > 6 times higher in skin flaps ≤ 5 mm. Thus, if the degree of remaining glandular tissue is acceptably low, it is desirable to create skin flaps thicker than 5 mm to prevent wound healing problems after the PM procedure.