Abstract
A 60-year-old woman was admitted to our hospital with chief complaints of left axillary lump and pain. A chest computed tomography (CT) scan and magnetic resonance imaging scan revealed a tumor (diameter, 4 cm) on the 3rd rib within the left chest wall. Ultrasonography showed a hypoechoic mass measuring 4 cm in diameter. Histological examination of the tumor after needle biopsy revealed benign granular cell tumor ; therefore, we resected the tumor that did not invade the left 3rd rib. Histological test revealed that the tumor was partly composed of vesicular nuclei with large nucteoli and pleomorphic cells and showed increased mitotic activity and vessel invasion. On the basis of these findings, we made a diagnosis of malignant granular cell tumor. The patient was free from recurrence and metastasis 1 year after the operation. Malignant granular cell tumor has a poor prognosis because of the high frequency of metastases, especially local metastasis and metastasis to the lymph nodes and lungs. Malignant granular cell tumor of the chest wall is very rare, and only 11 cases have been reported in the Japanese literature so far.
