[Differentialdiagnostic problems in fibrosarcoma of the foot (author's transl)]

3 cases of fibrosarcoma of the foot are presented. Despite a history of pain up to several years the first radiological examination did not reveal any signs of a malignant tumor. X-rays taken 1/2 to one year later showed a localized osteolytic process. Then the diagnosis was established by biopsy. Consecutive x-rays and timing for a biopsy are discussed.