A randomized trial was conducted at the Institut Gustave-Roussy (IGR) between 1972 and 1980 comparing tumorectomy and breast irradiation with modified radical mastectomy. One hundred and seventy-nine patients with an infiltrating breast carcinoma up to 20 mm in diameter at macroscopic examination were included: 88 had conservative management, and 91 a mastectomy. All patients had a low-axillary dissection with immediate histological examination. For the patients with positive axillary nodes, a complete axillary dissection was undertaken. Overall survival, distant metastasis, contralateral breast cancer and locoregional recurrence rates were not significantly different between the two treatment groups.