THE IMPORTANCE OF POSTOPERATIVE RADIATION-THERAPY IN MULTIMODALITY MANAGEMENT OF LOCALLY ADVANCED BREAST-CANCER - A PHASE-II TRIAL OF NEOADJUVANT MVAC, SURGERY, AND RADIATION

Purpose: To determine the impact of postoperative radiation on locoreg ional relapse and overall survival rate in a multimodality protocol fo r locally advanced breast cancer (LABC). Material and Methods: Of the patients entered in the protocol, 55 were evaluable. Treatment consist ed of: neoadjuvant MVAC (methotrexate, vinblastine, adriamycin, and ci splatin) until a maximum response had been achieved; modified radical mastectomy; 6 courses of postoperative adjuvant MVAC chemotherapy, and chest wall irradiation (CWXRT). Multivariate analysis of locoregional response and overall survival was done. Results: Of the total, 42 pat ients received chest wall radiation; 28 of these also received radiati on to regional lymph nodes. Chest wall doses ranged from 45 Gy to 50.4 Gy to the whole chest wall, with 31 patients receiving an additional chest-wall boost. The incidence of locoregional relapse with and witho ut radiation was 7% vs. 31%, respectively (p = 0.026). An overall surv ival benefit was seen in those receiving radiation, with a mean overal l survival of 50 months vs. 20 months, and a 3-year overall survival o f 88% vs. 46% with and without radiation, respectively (p = 0.003). Mu ltivariate analysis showed that overall survival was affected by the p resence of pathological CR (p = .047), the number of pre-operative che motherapy cycles (p = .036) and whether or not they received radiation (p = 0.003). Neither the interval between surgery and radiation, tech nique of radiation, nor radiation modality significantly affected loca l control. Conclusion: The significant improvement in local regional c ontrol and overall survival with the addition of radiation suggests th at radiation should be an integral part of multimodality management of locally advanced breast cancer. (C) 1998 Elsevier Science Inc.