From 1969 to 1983, 122 patients with unifocal breast cancer, equal or more than 3 centimeters in diameter, NON1a or N1b, were treated at the Institut Curie with conservative surgery after pre-operative external irradiation. Among them were 68% T2NON1a, and 26% N1b (with 21% T2N1b); 80% of the tumors were located in the upper part of the breast. Initial radiotherapy with a moderate dose (50 to 55 Gy for the breast and the lower axillary area) was followed 6 weeks later by a lumpectomy either alone (42 cases) or associated to an axillary node resection (80 cases). Five year survival rate with non evident disease T2NON1a cases is 79%, similar to the radical surgery rate in this group. We noted 8% local recurrences with no axillary recurrences. Post operative courses were a little more troubled than with initial lumpectomy. We noted 8% of upper limb oedema, only in patients who received both radiotherapy and surgery in the axilla. Cosmetic results are good in 65% of the cases, while they are good in 80% for initial lumpectomy. So this therapeutic method gives satisfactory results, but we need more cases with a longer follow-up to draw definitive conclusions.