Postmastectomy radiotherapy in intermediate risk stage I-II breast cancer patients.
OBJECTIVE
To evaluate the correlation of postmastectomy radiotherapy (PMRT) with local relapse rate, disease-free survival (DFS) and overall survival (OS) in a group of breast cancer (BC) patients at intermediate risk for locoregional relapse (stage I-II with either 1-3 positive axillary nodes, or node-negative grade III BC) treated with radical mastectomy.


METHODS
We evaluated 482 stage I-II BC patients, with either node-negative grade 3 tumors or with 1-3 positive nodes irrespective of tumor grade, treated with radical mastectomy at our Institute from 1986 to 1994. After mastectomy they received either adjuvant CMF (cyclophosphamide, methotrexate, 5-fluorouracil) chemotherapy (N=172), or adjuvant endocrine therapy (N=310). Postoperative radiotherapy (RT group) to the regional lymph nodes with tumor dose (TD) 48 Gy in 22 fractions was delivered to 199 patients.


RESULTS
After a median follow-up of 79.5 months, no difference in relapse rate between the two groups was seen (30.6% in the RT group vs. 36.7% in the no RT group; x(2), p=0.1). Local recurrence rate occurring alone or with distant metastases was 4.52% in the RT group vs. 7.77% in the no RT group (x(2), p=0.1). However, local recurrence rate alone was significantly higher in the RT group compared to the no RT group (2.01 vs. 6.01%, x(2), p=0.041). In premenopausal patients local relapses occurred in 3.2% of patients with postoperative RT and in 8.2% in patients without RT (Fisher's exact test, p=0.48). Non significant difference was registered in postmenopausal patients with (4.76%) or without RT (6.58%). Ten-year DFS and OS were 53.5% and 68.7% in the RT group vs. 52.9% and 75.2% in the no RT group (non significant difference).


CONCLUSIONS
Our results did not show that PMRT significantly influences the incidence of disease relapse, DFS and OS in stage I-II BC patients with intermediate risk for disease relapse. However, it seems that PMRT might influence the occurrence of locoregional recurrence in these patients.
Mladenovic
J
J
Department of Radiotherapy, Institute for Oncology and Radiology of Serbia, Belgrade, Serbia. mladenovicj@ncrc.ac.yu
Susnjar
S
S
Gavrilovic
D
D
Borojevic
N
N
D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D044584:Carcinoma, Ductal / Q000532:radiotherapy* / Q000556:secondary / Q000601:surgery; D018275:Carcinoma, Lobular / Q000532:radiotherapy* / Q000556:secondary / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008408:Mastectomy; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D015996:Survival Rate