Pleomorphic leiomyosarcoma of the adrenal gland with osteoclast-like giant cells.

Pleomorphic leiomyosarcoma (PLMS) of the adrenal gland is a rare tumor in an unusual location. A primary PLMS of the left adrenal gland is reported in a 59-yr-old Mexican woman who presented progressive flank pain and weight loss. The tumor measured 16 cm in diameter, showed markedly pleomorphic and osteoclast-like giant cells, necrosis, and high mitotic activity (average 15 per 10 high-power fields). The phenotype was supported by light microscopy and corroborated by immunohistochemistry. The neoplastic cells were strongly positive for muscle-specific actin, desmin, vimentin, and p53. They were negative for CD34, HMB45, estrogen receptors, and S-100 protein. The percentage of Ki-67 positive neoplastic cells was 7.6%. DNA content analysis by flow cytometry showed that tumor was diploid, with a high level of apoptosis. Extra-adrenal primary sites of origin were clinically excluded. The patient developed local recurrence and liver metastases 12 mo after initial treatment. She then received adjuvant chemotherapy and radiotherapy and the metastasis was resected. Twenty-four months later, she is alive with no evidence of disease. This is the second case of adrenal PLMS reported. This case exhibited a high histologic grade, aggressive behavior, and p53 overexpression, but diploid DNA content.