A rare case of giant cell tumor of the anterior rib presenting as a breast mass.

Initial diagnostic ultrasound of a 22-year-old female patient presenting with a palpable breast mass revealed a suspicious mass initially thought to arise from the breast. However, follow-up diagnostic mammography was normal without evidence of the 5 cm mass seen on ultrasound, and pathology results from ultrasound-guided core needle biopsy raised suspicion for giant cell tumor, making chest wall origin of the mass more likely. Further CT and MRI imaging indeed revealed a locally invasive mass arising from the anterior fifth rib. The patient was treated with denosumab to decrease tumor burden before surgery, and subsequently underwent successful surgical resection of the tumor with mesh overlay and flap reconstruction of the chest wall defect. This case highlights the importance of keeping chest wall lesions in the differential for lesions presenting clinically as breast lesions. Despite the rarity of giant cell tumor of the anterior rib and its unusual presentation as a breast mass, appropriate diagnostic imaging work-up allowed for successful diagnosis and treatment in this case.

A rare case of primary breast lymphoma presenting as calcifications on screening mammography.

Extranodal marginal zone lymphoma (EMZL) is a low-grade subtype of B-cell non-Hodgkin lymphoma that can affect any mucosal tissue, most commonly the GI tract. Primary involvement of the breast, known as primary breast lymphoma (PBL), is a very rare manifestation. We report an unusual case of a 65-year-old woman with primary breast EMZL presenting as calcifications discovered during screening mammography. This represents an exceedingly atypical appearance of primary breast lymphoma that is rarely described in the literature.

A rare case of synchronous mucosa-associated lymphoid tissue (MALT) lymphoma involving bilateral breasts and subcutaneous tissues.

Marginal zone lymphoma of mucosa-associated lymphoid tissue is a B-cell lymphoma which arises in extranodal sites, most commonly the stomach. Involvement of the breast is very rare. We present a case of an asymptomatic 63-year-old woman with synchronous mucosa-associated lymphoid tissue lymphoma involving both breasts and subcutaneous tissues. This represents a form of secondary breast lymphoma (given the concurrent involvement of the breast and non-mammary organ systems) and is an exceedingly rare diagnosis which, to our knowledge, has only been discussed in a few case series.