Pathological features of mucinous carcinoma of the breast are favourable for breast-conserving therapy

Aim: The effectiveness of breast-conserving therapy for mucinous carcinoma has not been well documented. We examined clinical and pathological feature s of cases to determine whether patients with mucinous carcinoma were suita ble candidates for this treatment. Method: Cases of pure type (n=52) and mixed type (n=24) mucinous carcinomas were reviewed with emphasis on the risk factors associated with local recu rrences after breast-conserving therapy. Results: Large pure mucinous carcinomas had a low incidence of extensive in traductal spreading (EIS). An inverse correlation existed between the incid ence of EIS and tumour size (P <0.05). Comedic, type EIS was infrequent (11 %) in pure mucinous carcinoma. Incidences of lymphatic vessel invasion (4%) and nodal involvement (4%) were lower in pure mucinous carcinoma than in m ixed carcinoma (P <0.05). No nodal involvement occurred in patients with pu re mucinous carcinoma less than 3 cm in diameter. Conclusions: Patients with pure mucinous carcinomas, except those invading the local skin, are suitable candidates for breast-conserving therapy. Most pure mucinous carcinomas, including a large tumour up to 5 cm in diameter, can be treated with this therapy. (C) 2001 Harcourt Publishers Ltd.