Lumpectomy (breast-conserving surgery)

Overview

• In triple-negative breast cancer chemotherapy is usually given first, and Cancer Research UK says shrinking the cancer may allow breast-conserving surgery instead of a mastectomy. Macmillan says breast-conserving surgery with radiotherapy is usually as effective as a mastectomy and that a second operation is needed if cancer is at the margin; NICE NG101 (2024) asks for further surgery when invasive cancer is at the radial margin and to consider it within 1 mm.
• Breast cancer, the long-term comparison with mastectomy. In the Milan trial, 701 women with breast cancers no larger than 2 cm were randomly assigned between 1973 and 1980 to radical (Halsted) mastectomy (349) or quadrantectomy followed by radiotherapy (352). After a median 20 years of follow-up, death from any cause had occurred in 41.2 percent of the radical mastectomy group and 41.7 percent of the conserving surgery group (P equals 1.0), and death from breast cancer in 24.3 and 26.1 percent (P equals 0.8). What differed was the breast: 30 women in the conserving group had a recurrence in the same breast against 8 local recurrences after radical mastectomy, a crude cumulative incidence of 8.8 against 2.3 percent, with no significant difference in contralateral cancers, distant metastases or second primary cancers.
• In NSABP B-06, 1,851 women were randomly assigned to total mastectomy, lumpectomy alone, or lumpectomy with breast irradiation, and followed for 20 years. Recurrence in the same breast occurred in 14.3 percent of those given radiotherapy against 39.2 percent of those not (P less than 0.001), and no significant difference was found between the three groups in disease-free survival, distant-disease-free survival or overall survival: the hazard ratio for death was 1.05 (0.90 to 1.23) for lumpectomy alone against total mastectomy and 0.97 (0.83 to 1.14) for lumpectomy with irradiation.
• NICE NG101 (1.13.3) says to offer whole-breast radiotherapy to women with invasive breast cancer who have had breast-conserving surgery with clear margins, and (1.13.4, 1.13.5) to consider partial-breast radiotherapy for women aged 50 and over with tumours 3 cm or less that are N0, ER-positive, HER2-negative and grade 1 to 2 who will take endocrine therapy for at least 5 years, telling them that local recurrence at 5 years is equivalent, that the risk beyond 5 years is not yet known, and that late adverse effects may be reduced.