Primary breast lymphoma: a pooled analysis of prognostic factors and survival in 93 cases

Primary breast lymphoma is a rare disease. The small number of patients and the paucity of data make large-series studies difficult. We conducted a pooled analysis to evaluate the treatment outcome and prognostic factors in patients with primary breast lymphoma. In a search of PUBMED and MEDLINE we found 7 observational studies with 93 patients that were eligible for inclusion. Treatments included single therapy or combined surgery, chemotherapy and radiotherapy. We analyzed the correlation between treatment protocols, tumor relapse and survival. Histopathology and cancer stage were analyzed to evaluate their significance in treatment outcome. All 93 patients were female, with a mean age of 57 years. The histopathology of 63 patients (68%) was diffuse large cell lymphoma. According to Ann Arbor classification, 57% were stage 1, 23% were stage II, 4% were stage III, and 16% were stage IV. Thirteen percent received surgery alone, 27% received chemotherapy alone, 7% received radiotherapy alone, 10% received surgery and chemotherapy, 10% received surgery and radiotherapy, 22% received chemotherapy and radiotherapy, and 11% received surgery combined with chemotherapy and radiotherapy. With a median follow-up duration of 34 months (mean, 53months), 48% had relapse of disease, 50% had no relapse, while 2% had disease progression. The mean time to first tumor relapse after treatment was 20 months. The 3-year and 5-year overall survival rates were 70% and 56% respectively. Radiotherapy was a significant prognostic factor predicting tumor relapse (P=0.044). Tumor stage was a significant prognostic affecting overall survival, disease-free survival and disease-specific survival (P=0.0231, 0.0015, 0.0124, respectively). With a 3-year overall survival rate of 70%, the high relapse rate of 48% is a cause for concern. Patients who received chemotherapy and radiotherapy had better survival outcome and a lower relapse rate. We suggest that chemotherapy and radiotherapy be the initial treatment for patients with primary breast lymphoma. (author)