Hamartoma of the breast: a clinicopathological review

Abstract

Aims: To review 25 cases of breast hamartoma and discuss the pathological criteria, and the usefulness of imaging modalities, fine needle aspiration cytology (FNAC), and needle core biopsy in the diagnosis. Methods: The hamartomas were assessed for interlobular fibrotic stroma, stromal adipose tissue content, pseudo-angiomatous stromal hyperplasia, and epithelial changes (hyperplasia, adenosis or apocrine metaplasia, and cyst formation). All imagings, previous FNACs, and biopsies were also reviewed. Results: Imaging (mammography, ultrasound, and magnetic resonance imaging) was performed in 18 cases, and mostly showed encapsulated masses with a heterogeneous appearance. Microscopically, all hamartomas demonstrated good demarcation with fibrous tissue condensation. Adipose tissue was noted in all cases (5-90%; mean, 31%), and interlobular fibrosis in 21 cases. Benign epithelial hyperplasia occurred in 10 cases, and pseudo-angiomatous stromal hyperplasia or cystic ducts in eight cases each. Apocrine metaplasia, calcification, stromal giant cells, and adenosis occurred in four cases or less. Two cases showed coexisting ductal carcinoma in situ limited to within the hamartoma. Needle core biopsies (four cases) and FNAC (14 cases) were largely insufficient, inconclusive, or nonspecific. Conclusions: Hamartomas do not possess specific diagnostic histological features. The role of FNAC and needle core biopsy in making the diagnosis is limited, and requires clinical and radiological correlation to avoid underdiagnosis.

Advanced MRI findings of breast hamartoma

“…However, hamartomas do not have specific diagnostic histological findings (4,5). Fine needle aspiration biopsy and core biopsy have limited roles in the diagnosis of hamartomas; therefore, the diagnosis of hamartomas may be fairly difficult.…”

“…Although they are benign, there is always a possibility of recurrence. Moreover, these lesions may coexist with in situ or invasive carcinomas (4,12,13). The malignancy itself may arise from glandular parts of hamartomatous tissues (13).…”

“…Breast hamartomas are benign lesions that appear with a frequency of 0.1−0.7% within all benign mammary masses (4). These lesions are also called fibroadenolipomas, lipofibroadenomas and adenolipomas.…”

Giant Breast Hamartoma: A Case Report in Togo

“…It can be associated with a mastodynia. The hamartoma is revealed most of the time during a palpation as a firm nodule, mobile benign characters such as adenofibroma [4] [10] [13] and this was the case of our patient. In addition, the absence of axillary adenomegaly, a criterion of benignity noted in our patient has also been reported [1] [12].…”

Concomitant Phyllodes Tumour and Hamartoma of the Breast

“…A simple surgical excision and removal of the entire Hamartoma of breast is normally sufficient treatment for big and symptomatic tumours, but a 'wait and watch' approach may be considered for asymptomatic hamartomas [3,4].…”