Osteosarcoma associated with absent thumbs: A report of two cases

An 8-year-old Hispanic boy with a hypoplastic left thumb, absent right thum b, and short stature experienced right leg pain and limp. A right tibial le sion was imaged and found to be osteosarcoma on biopsy. A 6-year-old Hispan ic girl with congenitally absent thumbs experienced a pathologic fracture o f her left femur after a minor sports injury. The radiologic abnormality se en was diagnosed as osteosarcoma on biopsy. Both patients continue to do we ll after intensive preoperative and postoperative high-dose chemotherapy an d definitive reconstructive limb surgery. Osteosarcoma has been linked to s everal congenital syndromes in which absent thumbs are a feature. These two patients with absent thumbs and no definable syndrome experiencing osteosa rcoma suggest that congenitally absent thumbs might be a risk factor for os teosarcoma in the absence of a syndrome.