Irradiated autografts effective following bone tumor removal

In a study, extracorporeally irradiated autografts led to significantly lower nonunion rates compared to segmental allografts.

Extracorporeally irradiated autografts can be an effective graft option following removal of malignant bone tumors, according to a study by surgeons in Taiwan.

Tain-Hsiung Chen, MD, and colleagues at the Taipei Veterans General Hospital and National Yang-Ming University, Taipei, reviewed 29 patients with malignant tumors who underwent intercalary resection between 1993 and 2001 at a mean 74 years of age. Diagnoses included 23 cases of high-grade osteosarcoma, two malignant fibrous histiocytomas, two chondrosarcomas, one leiomyosarcoma and one solitary plasmacytoma. The tumor locations included the femur in 20 cases, the tibia in six cases and the humerus in three cases, according to the study.

After surgeons removed a mean 16.8 cm length of bone, 14 patients underwent reconstruction using segmental allografts and 15 patients received extracorporeally irradiated autografts. The groups had no significant differences in terms of age, primary tumor type, tumor site or length of bone resected, according to the study.

Surgeons used extracorporeally irradiated autografts only if the patient’s resected bone had not been extensively destroyed, the authors noted. Before implantation, the autograft specimen had been treated with a radiation dose of 30,000 rads using a linear accelerator, followed by removal of the tumor and all soft tissues surrounding it, they said.

Graft fixation involved plates in 10 cases, intramedullary nails in four cases and intramedullary nails combined with one to two plates in 15 cases. All patients received neoadjuvant and adjuvant chemotherapy postop except the two patients diagnosed with chondrosarcoma, according to the study.

After a mean 71 months follow-up, 20 of the 29 patients (69%) were disease free. Five patients had died (17%), four patients (14%) survived but developed pulmonary metastases and one patient in each graft group required amputation following a local tumor recurrence, according to the study.

Three of the 15 irradiated autograft patients and two allograft patients suffered fractures seven to 83 months after implantation, but were treated successfully using immobilization or fixation. Patients implanted irradiated autografts had a higher but nonstatistically significant fracture rate, the authors said.

The segmental allograft group had a significantly higher rate of nonunion compared to the irradiated autograft group, having six of the seven cases seen in the study (P=.031). All cases healed uneventfully after additional plating or replacement of broken nails and implantation of autogenous bone grafts, however.

No patients required removal of either graft type and no patients developed infection, the authors noted.

“On the basis of our data, we conclude that intercalary allograft transplantation or extracorporeally irradiated autograft can provide a satisfactory solution to large skeletal defects created by wide intercalary excisions,” the authors said.

“The use of extracorporeally irradiated autograft could be an acceptable method of reconstruction after intercalary resection, especially in countries where it is difficult to obtain allografts,” they added.

For more information:
Chen TH, Chen WM, Huang CK. Reconstruction after intercalary resection of malignant bone tumors. J Bone Joint Surg Br. 2005;87-B:704-709.