Introduction. In the last 20 years, anthracycline and taxanes (AT) have been implemented in breast cancer treatment.The aim of this work is to estimate the prognostic factors and long-term disease-free survival in breast cancer patientsafter radical mastectomy and postoperative radiotherapy before implementation of AT.

Material and methods. The retrospective analysis included 470 post-mastectomy breast cancer patients in stage I–IIIB consecutively irradiated in the Cancer Center and Institute of Oncology in Warsaw from 1985 to 1994. The women were aged 26–77 years with a median of 56 years, and there were 80% with pN1-2 stage, and 20% with pN0. Simultaneously with radiotherapy 32% of patients received chemotherapy (CMF and/or Ansfield’a regimen) and 39% hormonotherapy (Tamoxifen). The median follow-up was 17.5 years. Disease free survival (DFS) and overall survival (OS) were analyzed by the Kaplan-Meier method, and prognostic factors were studied using the Cox’s proportional hazards regression model. To assess the function of the cumulative percentage of loco-regional recurrences (CPLRR) the competing risk method was used.

Results. 10-and 20-year DFS and OS rates were respectively 32% and 19%; 40% and 24%. 10-year and 20-year CPLRR rates and competing events: distant metastases, deaths from unknown causes, cancer of the second breast and other malignant tumours were respectively: 21% and 21%; 36% and 40%; 7.3% and 11.3%; 3.2% and 4.7%; 1.3% and 1.8%. Within the first 5 years, 69%, in 10 years 86%, and after 10 years 14% of breast cancer failures occurred. It was confirmed, that the strongest prognostic factor influencing both the DFS and OS was the number of involved axillary lymph nodes — above three (p = 0.0001). There were no statistically significant differences in the groups of patients with pN0 vs pN1-3 in both PB and PC. The presence of lymphoedema of the upper extremity and brachial plexopathy was correlated with post-mastectomy radiotherapy in 13.6% and 0.9% of patients. In one patient after 19 years of irradiation, squamous cell lung cancer was diagnosed in an area of low dose.

Conclusions. Post-mastectomy treatment resulted in a not very satisfactory survival of breast cancer patients. The 5-year follow-up period for breast cancer patients is too short to assess the results of the treatment, because even after 10 years the probability of recurrence or death due to breast cancer is high.