BREAST CONSERVATION - LONG-TERM AUSTRALIAN DATA

Long-term data on the management of early breast cancer in Australia by conservative surgery and radiation therapy is limited. To examine this issue we reviewed our experience of 131 patients with Stage I or II breast cancer treated between November 1979 and December 1985. Ninety patients had a T1 tumor and 41 a T2 tumor. The extent of surgery varied from a local excision (LE), a wide local excision, to a quadrantectomy or partial mastectomy. Sixty-two per cent of patients also had an axillary dissection. One hundred and nineteen patients were treated using 6Mev photons to the whole breast (Median dose; 50 Gy) +/- regional nodes followed by a single plane Iridium-192 boost to the primary tumor site (median dose; 30 Gy). Ten patients did not receive a boost and two elderly patients were treated with an implant only. The median follow-up of surviving patients was 83 months (range, 51-133 months). Six other patients were lost to follow-up at a median of 48 months (range, 4-62). The pattern of first relapse is: breast alone, 7.0%; breast + distant, 0.75%; breast + nodes, 0.75%; regional nodes only, 0.75%; and distant disease, 18%. The extent of surgery did not influence the probability of a recurrence in the primary tumor region. The time to a breast recurrence ranged from 12 to 127 months (median, 61 months). The 5-year actuarial rate of a breast recurrence was 4.5%. The 5-year freedom from distant relapse was 80%. The complications of treatment were acceptable. These included rib fracture (5%), symptomatic pneumonitis (4%), fat necrosis or fibrosis requiring surgery (4.5%), severe arm edema (4.5%). The treatment of the axilla by both surgery plus radiation therapy was associated with a moderate or severe arm edema rate of 29% compared to 8% for surgery alone and 6% for radiation therapy alone. Our long-term data indicate that conservative surgery plus radiation therapy is associated with low rates of breast cancer recurrence which are independent of the extent of surgical resection. Complications were acceptably low provided that the axilla was treated by surgery or radiation therapy but not by both modalities.