Primary breast lymphomas: a multicentric experience

The Primary Breast Lymphomas (PBL) represent 0,38-0,70% of all non-Hodgkin lymphomas (NHL), 1,7-2,2% of all extranodal NHL and only 0,04-0,5% of all breast cancer. Most frequent PBLs are the diffuse large B cell lymphomas; in any case-reports MALT lymphomas lack or are a rare occurrence. Their incidence is growing. From 1880 (first breast resection for "lymphadenoid sarcoma" carried out by Gross) to the recent past the gold standard treatment for such diseases was surgery. At present such role has lost some of its importance, and it is matter of debate.

Twenty-three women affected by PBL underwent surgery. Average age was 63 years (range: 39-83). Seven suffered of hypothyroidism secondary to autoimmune thyroiditis. Fourteen patients underwent mastectomy, nine patients received quadrantectomy (average neoplasm diameter: 1,85 cm, range: 1,1-2,6 cm). In 10 cases axillary dissection was carried out. Pathologic examination revealed 16 diffuse large B cell lymphomas and 7 MALT lymphomas.

Seven patients in the mastectomy group had a recurrence (50%), and all of them with diffuse large B cell lymphomas at stage II. Two of these had not received chemotherapy. No patient undergoing quadrantectomy had recurrence. In the mastectomy group disease free survival (DFS) at 5 and 10 years was 57 and 50%. Overall survival (OS) at 5 and 10 years was 71.4% and 57.1% respectively. All recurrences were systemic. DFS and OS at 5 and 10 years was 100% in the quadrantectomy group. In the patients with recurrence mortality was 85.7%. For stage IE DFS and OS at 5 and 10 years were 100%. For stage II DFS at 10 years was 62.5% and 56.2% respectively; OS at 5 and 10 years was 75% and 62.5% respectively. For MALT lymphomas DFS and OS at 5 and 10 years were 100%. For diffuse large B cell lymphomas DFS at 5 and 10 years was 62.5% and 56.2% respectively; OS at 5 and 10 years was 75% and 62,5% respectively.

The role of surgery in this disease should be limited to get a definitive diagnosis while for the staging and the treatment CT scan and chemio/radioterapy are repectively mandatory. MALT PBLs have a definitely better prognosis compared to large B cell lymphomas. The surgical treatment must always be oncologically radical (R0); mastectomy must not be carried out as a rule, but only when tissue sparing procedures are not feasible. Axillary dissection must always be performed for staging purposes, so avoiding the risk of under-staging II o IE, due to the possibility of clinically silent axillary node involvement.