Intramuscular Cavernous Hemangioma of the Breast

Breast hemangiomas represent only 0.4 per cent of all breast tumors, and cavernous hemangioma is the most common subtype.1 These vascular tumors are generally found in the breast tissue itself, but can also arise from the chest wall, as an intramuscular hemangioma. Intramuscular cavernous hemangioma is a rare pathological finding, accounting for less than 1 per cent of all hemangiomas. These benign vascular tumors are congenital in origin, with the majority presenting before age 30 years.2 The etiology is not completely understood, but patients with hemangiomas in other anatomical locations are more likely to develop a breast hemangioma. Most hemangiomas of the breast are small and asymptomatic and are found incidentally on mammogram or other imaging. They rarely present as a palpable breast mass. The pathology of the tumor is benign, and they carry an excellent prognosis. Providers may choose to closely observe asymptomatic hemangiomas, or they can be removed with complete surgical excision, which has a very low recurrence rate. The high rate of growth or development of significant signs or symptoms can be concerning for a malignant vascular tumor such as an angiosarcoma, which has a very poor prognosis.3 Our patient was a 54-year-old black postmenopausal woman who presented with a painless palpable breast mass, which had been present for three years. The patient reported a mass in the upper inner quadrant of the left breast, which had increased in size over the past year. The patient had a diagnostic bilateral mammogram one month before presentation because of concern for a left breast mass. Of note, there was no mammographic abnormality in the region of the mass felt by the patient in the upper inner quadrant, although there was a small area of increased density directly posterior to the palpable mass, which suggested a possible chest wall mass unable to be adequately included in the mammographic field of view. Left breast–targeted ultrasound demonstrated a solid mass in the left breast at the 10 o’clock position 10 cm from the nipple, measuring 1.7 · 1.6 · 0.9 cm, and a small adjacent mass, measuring 0.6 · 0.2 · 0.3 cm. An ultrasound-guided core needle biopsy was performed approximately one week later, with placement of a wing clip in the left breast mass. Pathology showed nonproliferative fibrocystic and fibroadenomatous changes with focal lymphoid aggregates. Although there was no evidence of malignant atypia, pathology only revealed a minute fragment of mammary tissue for evaluation. The lesion was considered suspicious on ultrasound, BI-RADS category 4. Because of discordant needle biopsy results, an excisional biopsy was recommended. Ultrasound demonstrated no evidence of suspicious lesions in the remainder of the left breast or the axilla. Ultrasound-guided excisional lumpectomy was performed, and it was discovered intraoperatively that the clip was not present in the initially excised breast tissue.