We report a case of myiasis of a rectocutaneous fistula in a subject suffering from bone metastases after surgical resection of a neoplastic bladder. The fistula was infested by maggots identified as third-instar larvae of flies belonging to the family Sarcophagidae, genus Sarcophaga. The infestation was neither intestinal nor pseudointestinal; it was probably caused by a fly ovipositing on the fistula of the patient while having wound care at home, even though the possibility that the infestation might have occurred during hospitalization cannot be ruled out.