ABSTRACT
To evaluate the treatment results and the prognostic factors after postmastectomy radiotherapy in patients with breast cancer.
One thousand four hundred ninety four patients treated with radiotherapy after mastectomy during January 1982-December 2002 were evaluated retrospectively. Radiotherapy was applied to the chest wall and also to the regional lymphatics in patients carrying high risk factors with 1.8-2 Gy daily fractions up to the total median dose of 50 Gy.
Median age was 49. Twenty-two patients (1.5%) had Stage I, 222 (14.9%) had Stage IIA, 421 (28.2%) had Stage IIB, 607 (40.6%) had Stage IIIA, 174 (11.6%) had Stage IIIB disease, 48 patients (3.2%) could not be staged due to Tx or Nx status. During a median follow-up duration of 46 months (range:6-276 months) 73 patients (4.8%) developed locoregional recurrence and 439 patients (29.3%) developed distant metastases. Five-year local-recurrence- free, disease-free and overall survival rates were 94.2%, 65.5% and 82.9% respectively. In multivariate analysis the only prognostic factor influencing local control was the number of metastatic axillary lymph nodes (p=0.029) and the prognostic factors affecting disease-free survival were T stage (p=0.042), nodal stage (p=0.041) and number of metastatic axillary lymph nodes (p=0.000) and the factors influencing overall survival were T stage (p=0.008), nodal stage (p=0.005), number of metastatic axillary lymph nodes (p=0.001), lymphovascular invasion (p=0.004) and histologic grade (p=0.042).
In the present study prognostic factors that affect loco-regional control, disease-free and overall survival after postmastectomy radiotherapy in patients with breast cancer were T stage, nodal stage, stage, the number of metastatic axillary lymph nodes, skin invasion and lymphovascular invasion.