[Carcinomatous degeneration of chronic osteomyelitic fistulae. 4 cases].

The occurrence of epidermoid carcinoma on fistulae of osteomyelitis has been known since the 19th century, and the four cases reported here show that this complication is still present. CASE-REPORTS. Four new cases developed on the tibia 33 to 54 years after the formation of fistulous osteomyelitis are presented here. The patients were three men and one woman, aged from 58 to 78 years. The lesions observed were ulcero-granuloma in three cases and common superficial ulceration in the fourth patient. In two out of four cases the diagnosis was difficult to ascertain and required deep surgical biopsy. The bone was invaded in three cases, but no regional or visceral metastases could be found. All patients were amputated, after failure of conservative radiotherapy in two of them. No recurrence was observed after a 2 to 3 1/2 years' follow-up. DISCUSSION. The frequency of this late complication cannot be measured precisely, but it has been estimated at 0.5 p. 100 of fistulous osteomyelitis. The warning signs are often not specific and delay the diagnosis; they consist of unusual pain, ulceration, granulation and discharge. The diagnosis rests on histology and requires a deep and wide surgical biopsy involving the entire sinus tract, but uncertainties sometimes persist concerning atypical pseudoepitheliomatous hyperplasia. The best treatment is amputation with removal and biopsy of regional lymph nodes when present, but it does not always avoid the occurrence of metastases which appear in 20 p. 100 of the cases, usually during the first three years following diagnosis. CONCLUSION. These four cases exemplify the need to consider this diagnosis in all patients showing changes in an old fistulous osteomyelitis and to confirm it by deep and wide biopsy.