Acta chir belg, 2005, 105, 658-659 Introduction Breast hamartoma is a rare benign lesion of the breast and has an uncertain origin (1). It is incidentally discov- ered during screening mammography (2). It is also referred to lipofibroadenoma, fibroadenolipoma or ade- nolipoma, based on predominant components. This tumour is generally diagnosed by mammographic exam- ination but its sonographic appearance varies greatly and is not helpful for differential diagnosis (3). Case report A 36-year old woman was admitted to our general surgery with complaint of a right breast mass since two months. Physical examination revealed a mass of about 10 cm diameter in the right breast. No axillary lympha- denopathy or contralateral mass was discovered. Ultra- sonographic and mammographic examinations revealed a 10 cm mass diagnosed as fibroadenolipoma (Fig. 1). Laboratory values were all within normal limits. Excisional biopsy was performed with circumareolar incision extending 1 cm long transversally on both sites of the areola. The lesion was 15 cm in diameter with a fatty appearance and a thin capsula (Fig. 2). There were multiple irregular pink areas of different sizes at cross section. These sites were examined for malignancy with frozen section histopathological exam- ination. The patient had no postoperative complications and was discharged on the 3 rd postoperative day. Histopathological examination of the 15  10  10 cm mass revealed a fibromatous hamartoma. No problem was noted during the follow-up, after 2 months. Discussion Hamartoma of the breast is first described in 1971 by ARRIGONI et al. (4). The frequency of the tumour is reported between 0,04%-1,15% (5), it accounts for 4,8% of all benign breast tumours (6). Pregnancy and lactation are considered to be related to the pathogenesis (7). However, in the study by HELVIS et al. (10), 53% of the patients were nulliparous. The lesions are usually pain- less and palpable as a relatively soft mass. Occasionally, the masses may grow to 9 cm and remain non palpable. Mammographic examinations usually describe mam- mary hamartoma as a circumscribed, non homogeneous tumour, consisting of fatty tissue interspersed with an area of density similar to that of normal glandular tissue. Breast Hamartoma : a Case Report U. Barbaros, U. Deveci,Y. Erbil, D. Budak Department of General Surgery, Istanbul Medical School, Istanbul University, Istanbul, Turkey. Key words. Hamartoma ; breast. Abstract. Breast hamartoma is a benign and rare tumour consisting of glandular fat and fibrous tissue. A 36-year old woman was admitted to our clinic, complaining of a mass in her right breast since two months. Ultrasonographic and mammographic examinations revealed a 10 cm mass diagnosed as fibroadenolipoma. Total excision of the mass was performed without any complication. Histopathological examination revealed fibroadenomatous hamartoma. Fig. 1