A 64-year-old man was admitted to our hospital complaining of non-productive cough and right chest pain. Chest radiographs showed bilateral hilar lymphadenopathy, diffuse granular nodules and right pleural effusion. Serumangiotensin-II-converting enzymeand lysozyme levels were elevated. Since thoracentesis indicated bloody pleurisy, video-assisted thoracoscopy was performed and revealed multiple white nodules on both the visceral and parietal pleura. Resected pleural biopsy specimens showed non-caseous granulomas. Furthermore, somenodules were observed to compress and involve small vessels and capillaries. The bloody pleurisy was assumed to have been derived from the rupture of small vessels that had been compressed and affected by the granuloma with sarcoidosis.

We report an unusual case of stromal sarcoma of the breast with leiomyosarcomatous pattern, which recurred locally and was finally treated by radical mastectomy. The tumor was composed of pleomorphic and hyperchromatic spindle-shaped cells arranged in an interdigitating fascicle. The nuclei were of moderate to severe atypia. An average of 10 mitoses per 10 high-power fields was seen. Immunohistochemically, the stromal cells were positive for vimentin and alpha-smooth muscle actin, but negative for S-100 protein, cytokeratin and desmin. The average Ki-67 (MIB1) labeling index in the stromal cells was 34%. Electron microscopic evaluation revealed further evidence of smooth muscle differentiation; stromal cells had frequently indented nuclei, well-developed rough endoplasmic reticulum, thin basal lamina and dense patch-like structures within the cytoplasm. Analysis of previous literature on 17 cases reveals mitotic activity of the tumor seemingly of little prognostic value. This case indicated difficulty in diagnosing leiomyosarcoma. The risk of local recurrence remains even if the surgical margin is free of tumor cells.