[Conservative treatment of multifocal breast cancer: a comparative study].

Conservative treatment of multifocal breast cancer is still very controversial. This retrospective study concerns 56 patients with stage I or II multifocal breast cancer who underwent conservative treatment at the Institut Curie from January 1983 to December 1989. These patients (group 1) were matched with 132 patients with multifocal lesions treated by mastectomy (group 2). Surgical treatment consisted of a single wide lumpectomy followed by external radiotherapy. Adjuvant systemic therapy and regional nodal irradiation were administered as indicated by current protocols. The actuarial 5-year overall survival rate was 94% 6 in group 1, and 90% 6 in group 2 (NS). The actuarial 5-year ipsilateral breast recurrence rate was 11% 8 in group 1, and 11% 5 in group 2 (NS). In group 1 patients, the ipsilateral breast recurrence rate was related neither to type of multifocality nor to presence of intra ductal breast carcinoma, nodal status, tumor margins, radiotherapy boost, or distance between tumors. Consequently, conservative treatment of multifocal breast cancers which can be completely removed by a single lumpectomy seems, when technically feasible, an alternative to mastectomy.