Evaluation of bone grafting for treatment of low-grade chondrosarcoma of long bones

Abstract

Objective: To retrospectively analyze the biological compatibility and oncologic outcomes of autogenous, allogeneic, or combined bone grafting.

Methods: From April 2000 to December 2016, 37 patients with histologically confirmed low-grade intramedullary chondrosarcoma of the long bones at Kyungpook National University Hospital were enrolled in this retrospective study. All 37 patients underwent intralesional curettage (with or without cryotherapy) followed by bone grafting. Among the 24 patients who underwent cryotherapy, 13 were treated by prophylactic internal fixation (10 in the femur, 1 in the tibia, and 2 in the humerus). Thirteen patients underwent the same treatment without cryotherapy, whereas 12 did not undergo preventive internal fixation.

Results: A single intraoperative fracture was managed by plate fixation. One patient who underwent cryotherapy and internal fixation developed a fracture distal to the operation site 25 days after surgery, and this fracture was repaired with a long plate. None of the 37 patients showed any recurrence or metastasis.

Conclusions: Adequate intralesional curettage (with or without cryosurgery) combined with bone grafting using autogenous and allogeneic bone chips was effective for the treatment of low-grade intramedullary chondrosarcoma. Therefore, prophylactic internal fixation using a plate is recommended in the cryotherapy of definite cortical invasion in weight-bearing bones.

Keywords: Low-grade chondrosarcoma; bone graft; cryosurgery; curettage; internal fixation; long bone.

Figure 1.

(a, b) Calculation of tumor volume using the ellipsoid volume formula 4/3 π ×  $\frac{a}{2}$ × $\frac{b}{2}$ × $\frac{c}{2}$ , where a is the maximum transverse diameter in the coronal section, b is the longitudinal diameter in the coronal section, and c is the maximum transverse diameter in the sagittal section obtained by T2-weighted magnetic resonance imaging.

Figure 2.

(a, b) A large amount of lobulated cartilage-like stroma was observed in the intramedullary femoral shaft with low signal intensity on T1-weighted magnetic resonance imaging and high signal intensity on T2-weighted magnetic resonance imaging. (c, d) Computed tomography and preoperative radiography showing massive chondrogenic punctate calcification in the intramedullary femoral shaft. (e) Radiography immediately after intralesional curettage with cryotherapy followed by bone grafting and internal fixation. (f) Radiography 2.3 years after surgery showing that the bone had healed well after removal of the plate and screws because of discomfort from the heaviness of the plate.

Figure 3.

(a) Preoperative radiography showing a lytic lesion with slight chondrogenic calcification in the proximal humerus. (b, c) The intramedullary low signal intensity on T1-weighted magnetic resonance imaging and high signal intensity on T2-weighted magnetic resonance imaging indicates the presence of a chondromatous matrix in the lesion. (d) Technetium-99m bone scintigraphy showing characteristic hot uptake. (e) Computed tomography showing the presence of dense intramedullary calcifications in the proximal humerus. (f) Postoperative pathology showing mild atypical cells and extensive mucinous degeneration of cartilage-like matrix (×100, hematoxylin–eosin).

Figure 4.

(a, b) T1- and T2-weighted magnetic resonance imaging 2.5 years after the surgery showing that the incorporated bone graft appeared healthy. A slightly increased signal of bone marrow edema was present. (c) Radiography 4.5 years after the surgery showing good healing of the bone graft. (d) Technetium-99m bone scintigraphy showing only slightly increased uptake at the operation site.