Postmastectomy Radiotherapy in Intermediate-Risk Patients: Long Term Carcinologic and Quality of Life Results of the Montpellier Cancer Center.

Abstract

Abstract Background:The impact of postmastectomy radiotherapy (PMRT) on survival has been controversial for decade in intermediate-risk patients.We present here our monocentric long-term carcinologic and quality of life results in the subset of patients classified at intermediate risk and treated with PMRT.Material and Methods: From 1990 to 2000, 1622 patients received adjuvant radiotherapy after mastectomy. Among them, 421 were defined at intermediate risk of local recurrence i.e. (i) one to 3 positive nodes (ii) negative node but younger than 35 years old and/or pT3-T4 and/or grade 3 and/or invasive multifocality and/or lymphovascular invasion. PMRT consisted in a 50 Gy-electron therapy to the chest wall with node irradiation if indicated. Adjuvant chemotherapy and/or hormonotherapy were administered according to our local guideline. Patients were visited every 6 months for at least 10 years. Quality of life questionnaires (EORTC QLQC30/BR23) were filled in at the last medical visit.Results: Median age was 57 years (range, 27-80). One-hundred thirty five patients (32%) and 286 (68%) were premenopausal and menopausal, respectively. Seventy-five percent of the patients presented a ductal invasive carcinoma and 55% one to three positive axillary nodes. The median number of nodes was 13 (range, 3-27). 77% of the patients presented an axillary dissection with more than 10 nodes. 32% of the nodes were associated with capsular effraction. In the node negative subgroups, grade 3, lymphovascular invasion, multifocality, pT3-4, and age < 35 were found in 57%, 19%, 33%, and 4%, respectively. Extensive DCIS was found in 227 patients (54%). Hormonal receptors (ER and/or PR) were positive in 321 patients (76%) and therefore treated with postoperative tamoxifen for 5 years. Adjuvant chemotherapy was delivered in 126 patients and mainly included anthracyclin. HER2 status was not available at that time in our center. Chest wall RT was delivered in all patients to a median total dose of 50 Gy (range, 43-62). Sus-clavicular and internal mammary chain were irradiated in 294 and 346 patients, respectively. With a 10-y median follow-up, 12 (2.8%) and 74 (17.6%) patients presented locoregional and metastatic recurrences, respectively. Locoregional-free survival (LRFS) was 98.3% and 97.1% at 5 and 10 years, respectively. None of the 12 patients presented metastasis before local recurrence. Multifactorial analysis showed a significant impact of LRFS on metastatic-free survival (p<0.001). Quality of life was good to excellent.Conclusion: In this study, only 2.8% recurrences were observed with a very long-term follow-up. Local recurrence is one of the main prognostic factors for metastatic progression. RT in this population seems to be clearly indicated. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4112.