Primary breast lymphoma.

Primary breast lymphoma (PBL) is a rare form of localized extranodal lymphoma. Few reports are available in the literature concerning its treatment and outcome. Of the 34 cases of PBL seen at our institution over a 25-year period, 20 consecutive cases were treated with CHOP or CHOP-like chemotherapy regimen and had adequate biopsy specimens for histological review. All these 20 PBL were of B-cell origin including one case of Burkitt lymphoma, and 2 cases of low-grade histologic type. Sixteen of the 20 patients achieved a complete remission (CR) and 2 achieved a partial remission (PR) (>75% tumor regression). Two patients had progressive disease while on therapy. With a median follow-up period of 80 months, 6 patients relapsed. Median time to relapse from diagnosis was 23 months (range, 3-41 months). Two of the relapses involved the central nervous system (CNS): isolated CNS relapse in one case and associated with other relapse sites in 1 case. The two patients who achieved a PR after chemotherapy also had disease progression to the CNS, 4 and 8 months after the end of CHOP chemotherapy. All 4 patients died of their disease 3, 6, 10 and 13 months after CNS involvement. Of the 16 centroblastic diffuse large B-cell lymphoma (DLCL), 3 had CNS disease at relapse. Three (15%) of our study patients developed a controlateral breast relapse. Twelve of the initial 20 patients were alive, including 11 with a persistent CR, 6 patients died of their lymphoma and 2 of unrelated diseases. In conclusion, we observed a high incidence of CNS relapse in this group of localized extranodal lymphoma, strongly suggesting that CNS prophylaxis should be associated with systemic chemotherapy in localized PLB.