DIAGNOSIS: Cardiac myxoma
This lesion features myxoid stroma and bland stromal cells which cluster around blood vessels. There’s a background of chronic inflammation, and hemosiderin deposition onto elastic fibers. Also on the slide there are areas of superimposed organizing thrombus. These findings are diagnostic of a cardiac myxoma.
An organizing thrombus would lack the extensive myxoid areas with characteristic perivascular spindle cells of cardiac myxoma. Mucinous carcinoma and myxofibrosarcoma would show greater degrees of cytologic atypia, and can also be excluded by clinical history.
Cardiac myxomas are part of the Carney Complex, which includes cutaneous pigmentation around the lips, cardiac myxoma, cutaneous angiomyxoma, myxoid fibroadenoma, pigmented nodular adrenal cortical disease, large cell calcifying Sertoli cell tumor of the testis, pituitary adenoma, blue nevi and, psammomatous melanotic schwannoma.
Source: Johns Hopkins Surgical Pathology Conference