BACKGROUND: Subcutaneous mastectomy in female to male transsexuals is one first important step in gender adjustment. Beside proper surgical technique, operative management of mastectomy procedures is important to allow for an optimised process of gender transformation including all necessary individual operations. METHODS: 126 female-to-male transsexuals were prospectively included in the observation period, all undergoing a step 1 operation of gender adjustment. The mastectomy procedure is conventionally embedded in an overall approach for gender transformation and was regularly combined with procedures like colpectomy, extension of the urethra as well as hysterectomy and ovariectomy. 4 different methods for mastectomy were introduced at our institution, depending on and adjusted to the breast volume, grade of breast ptosis, the breast size and envelope and skin elasticity. For patient evaluation a standardised survey was conducted using a semiquantitative score (1-4) for grading aesthetic results and nipple sensibility. RESULTS: Between 2006 and 2009 a total of 126 patients underwent a step 1 procedure of gender adjustment, 63 had mastectomy and 29 a revision procedure after external prior mastectomy. In 64/126 (50.8%) mastectomy was performed using a one-third edge cut, 30/126 (23.8%) were operated by a submammarian approach and pedicled nipples technique, in another 22/126 cases (17.5%) mastectomy was performed using circular tightening and 10/126 (7.9%) received freely transplanted nipples. For improving the aesthetic results, additional procedures were performed on 29 patients (46%). The patient survey revealed a high level of satisfaction with the aesthetic result, 42/50 (84%) of the patients rated results as good or very good. CONCLUSIONS: We newly introduced an operative concept of mastectomy being embedded and adjusted in an overall approach for gender adjustment (Munich Modular Operative Kit; MMOK). Using the presented individualised surgical techniques of mastectomy, all procedures were conducted in a very scar-saving manner, however, a higher rate of correction procedures was necessary to individually adjust skin shrinking and thereby optimising the prior aesthetic results. The new Munich Modular Operative Kit allows for gender reassignment including breast corrections usually using 4 operative steps.