Malignancy, aggressiveness, and recurrence in giant cell tumor of bone

Abstract

Eighty-six cases of giant cell bone tumor were reviewed with particular attention to frank sarcomatous changes, abnormal mitoses, permeation of vascular channels, and the number of mitoses per square millimeter, and the results were analyzed in relation to malignancy, aggressiveness, and recurrence. There were 4 cases of malignant (Grade III) tumor (about 5%) showing frank sarcomatous changes. Eight (9%) were considered cases of borderline (Grade II+) tumor, without frank sarcomatous changes but showing abnormal mitoses or vascular permeation. Seventy-four (86%) were cases of conventional giant cell tumor (Grades I and II). Mitotic counts did not categorically distinguish the three groups because of overlap. Recurrence essentially reflected the inadequacy of treatment. Metastases were observed only in the malignant group. About a quarter of conventional giant cell tumors were considered aggressive on clinical or radiologic grounds, but these could not be identified on a histologic basis. Tumors with minimal mitotic activity (1/mm2 or less) were almost exclusively nonaggressive. Post-irradiation sarcomas, best regarded as independent new tumors, developed in 4 cases (about 5%).

Metastatic Giant Cell Tumor of Bone: Are There Associated Factors and Best Treatment Modalities?

“…Authors have suggested several etiologies and mechanisms of metastasis in GCT including transformation from a self-limited benign course and true arterial metastasis [4,8,15,16,18]. Postulated mechanisms could be either embolism or active ''biologic predeterminism'' of the giant cells to invade the interstitium, destroy vessel walls, and intravasate by means of enzymes with subsequent lodgment and growth in target organs [4].…”

“…Postulated mechanisms could be either embolism or active ''biologic predeterminism'' of the giant cells to invade the interstitium, destroy vessel walls, and intravasate by means of enzymes with subsequent lodgment and growth in target organs [4]. There also is debate regarding whether surgical manipulation promotes pulmonary metastasis [4,8,15,16,18].…”

The prognostic significance of DNA cytophotometry and proliferation index (Ki-67) in giant cell tumors of bone

“…Jaffe et al [18], Dahlin et al [8], and Huvös [17] classified GCT into 3 grades by its histological appearance, but the clinical and prognostic value of this grading has been disputed because these criteria are, in part, subject to personal bias [9,26].…”

Distribution and prognostic significance of human telomerase reverse transcriptase (hTERT) expression in giant-cell tumor of bone

“…Unfortunately, the usual lightmicroscopic features associated with aggressive clinical behavior in most neoplasms, including necrosis, mitotic activity and even vascular invasion, do not predict outcome in giant-cell tumor. 1,8 The discrepancy between histopathology and clinical course may stem from the heterogeneous population of cells that constitute giant-cell tumor. More specifically, culture experiments suggest that the neoplastic cells of giant-cell tumor represent only a small subset of a mixed population of cells that include monocyte-macrophages, osteoclast-like giant cells and others.…”

“…Some authors have suggested that radiologic grade simply predicts the likelihood of adequate treatment, and it is the latter that influences clinical behavior. 8 Giant-cell tumor is typically treated with intralesional curettage, burring and packing with cement or bone graft. More aggressive treatment protocols involve resection so as to achieve wider margins than are customarily accomplished with intralesional curettage procedures.…”