A case of metacarpal coloboma caused by Tumor-induced Osteomalacia treated with bone cement prosthesis and literature review

Abstract Tumor-induced osteomalacia (TIO) is a rare disease known as hypophosphoric osteomalacia (HO). Phosphaturic mesenchymal tumor (PMT) is the pathological basis of most TIO patients and is caused by abnormal secretion of fibroblast growth factor 23 (Fibroblast Growth Factor 23, PMT). FGF-23 causes abnormal renal phosphate consumption and hypophosphatemia and is often subject to repeated examination and treatment before diagnosis, and the process of definitive diagnosis usually lasts several years. Most of these patients can be cured by surgical resection of the tumor, but the tumor causing this disease is often small in size, hidden in location, and difficult to detect. Multiple examination methods are needed to determine the location of the tumor, and cases of complete bone loss caused by direct tumor erosion have not been reported in the literature. We report a case in which the third metacarpal bone was lost due to direct tumor erosion, which was treated with prostheses made of bone cement. We also reviewed the relevant literature to explore the diagnosis of tumor-related osteomalacia and the treatment strategy used for this extremely rare case.