The First Case of HER2+ Invasive Ductal Carcinoma Arising From a Breast Hamartoma and Literature Review

Breast Hamartoma: Clinical, Radiological, and Histopathological Evaluation

Objective

Breast hamartomas are rare, benign, and slow-growing breast tumors that can be definitively diagnosed by combining the results of clinical, radiological, and histopathological examination. This study aimed to evaluate the clinical, radiological, and histopathological features of hamartomas and summarize our clinical approach to hamartomas.

Materials and Methods

Patients diagnosed with breast hamartoma between 2010 and 2020 in our clinic were retrospectively analyzed. Demographic information, clinical examination, radiological findings, histopathological features, changes during follow-up, and follow-up data were obtained and analyzed.

Results

Of the 1,429 patients operated on in our clinic for benign breast diseases between January 2010 and March 2020, 39 (2.7%) were diagnosed with breast hamartomas with histopathological examination. All patients were women with a median age of 37 (19-62) years. Most of the patients (64%) were in the premenopausal period. Radiological examinations were conducted using mammography (66%), breast ultrasonography (100%), and breast magnetic resonance imaging (48%). Biopsy was performed in 14 preoperative patients, and nine (64%) patients were diagnosed with hamartoma. All patients were operated on; 37 patients underwent a lumpectomy, and two had a mastectomy. No patients had hamartoma recurrence during an average follow-up period of 39 months.

Conclusion

Hamartomas are similar to other benign breast pathologies. Definitive diagnosis can be achieved by combining the results of clinical, radiological, and histopathological examination. Given its similar composition to normal breast tissue, hamartoma has a low rate of malignancy. Definitive diagnosis and appropriate surgical treatment are required.

Our 20-Year Institutional Experience with Surgical Approach for Breast Hamartomas

Objective

Hamartomas are rare, slowly-growing breast tumours. Clinical, radiological and histopathological examination together increase the diagnostic accuracy. To evaluate the clinicopathologic features of hamartomas and outline our clinical approach to hamartomas in our 20-year experience at our Breast Clinic.

Materials and Methods

Between 1995 and 2015, 24 cases were retrospectively analyzed with a diagnosis of breast hamartoma at our Breast Clinic followed by excisional biopsy. Data was obtained on patient demographics, clinical examination, radiological findings and histopathological subtypes.

Results

Of 1338 benign breast tumours excised from January 1995 to January 2015, 24 (1.8%) were identified as breast hamartoma. Median age of patients was 42 (range, 13-70), whereas the median tumour size was 5 cm (1-10 cm). On preoperative imaging, hamartoma was most commonly misdiagnosed as fibroadenoma. Pathological examination of the 24 biopsy specimens revealed 3 cases with pseudoangiomatous stromal hyperplasia, and another hamartoma associated with a radial scar within the centre of the lesion. Of those, one patient was diagnosed with malignant phylloides tumour in the same breast. At a median follow-up 58.4 months, none of the patients recurred or developed malignancy.

Conclusion

Hamartomas can often be missed by clinicians, due to its benign nature which is poorly understood. Despite their slow growth, hamartomas can reach large sizes and can cause breast asymmetry. Although it is rare, hamartoma can be seen along with malignancy, as it is formed from similar components of breast tissue. Therefore, careful diagnosis and appropriate management including surgery are required.