Abstract
A 62-year-old man has had a walnut-sized, asymptomatic, subcutaneous tumor on the left thigh for longer than 1 year without remarkable change. The tumor did not migrate from the primary site, but the tumor volume reduced to fingertip-size during the course of 3 months. Total resection was performed under a possible diagnosis of epidermal cyst. A histopathological examination revealed parasite bodies in adipose tissue, which had several characteristic features for plerocercoid and granulomatous change with infiltrarion of lymphocytes and eosinophils around parasites. From these findings, a diagnosis of Sparganosis mansoni was made. Although the ingestion of uncooked flesh or untreated water usually causes Sparganosis, the infection route in the present case was not defined. The specific anti-plerocercoid antibody with multiple-dot ELISA method was strongly positive 3 months after surgical removal of the lesion, and decreased but still positive 3 months later. Then praziquantel was orally administered without recurrence for almost 1 year after resection.
