An ultrastructural and histochemical study of alveolar soft part sarcoma with special reference to the nature of crystals

We have presented a case of typical alveolar soft part sarcoma probably originating from the soft tissues of the retroperitoneum with metastasis to the brain. An ultrastructural study including histochemical observation of the metastatic lesion was performed to clarify the nature of the crystals characteristic to the tumor cells of this disease. The crystalline structures have acid phosphatase activity at a histological and ultrastructural level. Our results suggested that they might be derived from coalescence of primary lysosomes or by digestive disintegration of some protein.