The Use of Irradiated Allografts in Reconstruction of Tumor Defects – the Tata Memorial Hospital Experience

Abstract

A Tissue Bank is a valuable adjunct to tumour management. In bone tumours, the defects produced by ablative surgery can be reconstructed using banked tissue, thereby obviating the donor site morbidity associated with autografts. Allografts are especially useful in large defects or in children where the quantity of available autograft is limited. The use of bone allografts in India has been limited by the availability of good quality, affordable grafts. In this article we share our experience with the use of indigenously produced allografts in limb salvage, as bone graft expanders and as struts. Lyophilised, irradiated bone allografts were morcellised and used in 32 patients. In 21 of these patients the allograft was used in contained cavities. Complete incorporation of the graft was seen between 6-9 months in all the 25 cases available for follow-up. In 4 patients the allograft was layered onto autograft. The allograft incorporated with the host bone in only one of these patients.Struts were used in 9 cases (3 cases complete intercalary segmental defect, 3 cases of hemicortical defects, 2 cases of allograft-prosthesis composite around the hip, 1 case an iliac-crest block was used to stop bleeding from an anterior sacral defect). Of these, no incorporation of the full segment struts was observed in 2 patients who were on chemotherapy and radiotherapy. The sacral defect case was lost to follow-up. All the other struts incorporated with the host bone within 6-9 months. In 5 cases there was sterile postoperative drainage. Overall infection was observed in 4 patients (10%). In one the graft was removed, another settled uneventfully with subsequent incorporation of graft, and two have a persisting sinus but good incorporation. Since radiation and lyophilisation are known to affect the material properties of bone, the grafts were rehydrated in saline for 30 minutes prior to transplantation. Autogenous marrow or autograft was used to provide osteoinductive properties. In selected cases the lyophilised, irradiated bone allografts proved to be clinically useful in the reconstruction of large tumour defects.

Total hip replacement for proximal femoral tumours: our midterm results

“…The integration of the graft into the host bone may provide a more secure long-term reconstruction. A specimen of the appropriate size and shape is easy to obtain, and this facilitates reconstruction [9,19].…”

Fresh‐frozen allogeneic bone blocks grafts for alveolar ridge augmentation: Biological and clinical aspects

“…Nevertheless, harvesting an AT bone block, has drawbacks; surgery is relatively cumbersome, as it often necessitates the use of a second surgical site, thus adding to patient suffering due to donor site morbidity, extended surgical time, and increased post-surgical pain; there is also a risk for nerve and soft tissue injuries; and occasionally, the quality and quantity of available bone does not allow harvesting of a bone block, for example, in small size jaws after long-term edentulism. 28,29 Allogeneic (AL) bone, in particular fresh-frozen bone (FFB) blocks (i.e., collected from another human, deceased or alive) have been proposed as an alternative to AT bone blocks 30,31 ; AL bone is in general a widely used material, not only in dentistry, but also in orthopedics, with the obvious advantages of unlimited availability and reduced surgical time. 32 Concerns of the past about the use of AL bone, in terms of risk of disease transmission (e.g., hepatitis or HIV) and antigenicity 33,34 have been lessened during recent years due to the very strict guidelines for donor bone tissue sources and processing.…”

“…Therefore, AT bone grafts are often referred to as the gold standard. Nevertheless, harvesting an AT bone block, has drawbacks; surgery is relatively cumbersome, as it often necessitates the use of a second surgical site, thus adding to patient suffering due to donor site morbidity, extended surgical time, and increased post‐surgical pain; there is also a risk for nerve and soft tissue injuries; and occasionally, the quality and quantity of available bone does not allow harvesting of a bone block, for example, in small size jaws after long‐term edentulism 28,29 …”