Over 20 years, 470 cases of giant cell tumor of bone diagnosed at a tertiary cancer hospital were analyzed. Male predominance (57%), predilection for bones around the knee joint (42%), and occurence in the 21- to 30-year-old age group (49.1%) with 6% being in the immature skeleton are well known facts. Accurate diagnosis was possible in 66% and 88% of cases on radiology and biopsy, respectively. Tumors measured 6 to 20 cm and, in 402 cases, showed "usual" histology comprising uniformly scattered multinucleate giant cells amidst mononuclear stromal cells, together imparting a syncitium-like appearance. Presence of osteoid, hemorrhage, and aneurysmal bone cyst-like areas; spindle cells in sheets (devoid of giant cells); or storiform pattern and intravascular osteoclasts were less common. The less common histologic features posed diagnostic difficulty in the setting of a small biopsy. Treatment included intralesional curettage (33.19%), marginal excision (4.2%), wide excision (31%), or radical surgeries (14.25%). Recurrences seen in 170 cases were multiple in 47 cases. Metastases largely to the lung were recorded in 24 cases. The histology of all the tumors, namely, primary, recurrent, or metastatic was identical. Statistical analysis using the computer software SPSS (SPSS Inc, Chicago, Ill)was performed with particular reference to the unusual histologic features vs recurrence and metastasis by chi(2) test. The only statistically significant factors were occurrence in the axial skeleton vs appendicular skeleton (P = .001) and primary treatment elsewhere vs at this hospital (P = .045), each of these being associated with increased frequency for local recurrence but not metastasis.