Extraskeletal Myxoid Chondrosarcoma Presenting as a Plantar Fibroma: Case Report and Review of the Literature.

BACKGROUND: Extraskeletal myxoid chondrosarcoma is a rare tumor with an indolent course, high propensity for local recurrence, metastases, and propensity for the proximal extremities of middle-aged males. CASE REPORT: We present the case of a 44-year-old man with an extraskeletal myxoid chondrosarcoma in the plantar fascia of the medial arch initially thought to be a plantar fibroma. Magnetic resonance imaging of the lesion demonstrated a lobulated subcutaneous mass plantar to the tarsal bones and inseparable from the fascia. Microscopic examination revealed a lobulated lesion composed of cords and nests of round to spindled malignant cells in a blue-gray myxoid matrix surrounded by fibrous septae. The malignant cells displayed variable positivity for S-100. CONCLUSION: Plantar extraskeletal myxoid chondrosarcoma is a rare occurrence. It should always be considered in the differential diagnosis of masses arising in the plantar fascia of the foot.

Concurrent primary peritoneal low-grade serous carcinoma and endometrial high-grade serous carcinoma.

A 64-yr-old postmenopausal woman with high-grade squamous intraepithelial lesion and atypical glandular cell of undetermined significance on her Pap test was found to have endometrial serous carcinoma (high grade) involving a polyp in a subsequent endometrial biopsy. She underwent hysterectomy and bilateral salpingo-oophorectomy with multiple biopsies of the peritoneum. Microscopic examination of the entirely submitted uterus showed no residual serous carcinoma. Multiple foci of low-grade serous tumor with extensive calcifications and psammoma bodies were identified on the surfaces of the left fallopian tube, ovaries, and biopsies of the peritoneum, consistent with peritoneal primary low-grade serous carcinoma. To our knowledge, this is the first reported case of low-grade serous carcinoma of the peritoneum with a concurrent (high-grade) serous carcinoma of the endometrium arising from an endometrial polyp.