Giant-cell tumor (GCT) of the pelvis is uncommon, accounting for only 1.5 to 6% of cases of GCT.Cheng MT, Chen TH, Chen WM. Periacetabular giant cell tumor treated with intralesional excision and allograft reconstruction. J Chin Med Assoc 2004;67:537-41 In pelvis ilium is the most common site of involvement; ischium and pubis are less frequently involved.Patne SC, Kumar M, Sadaf L. Giant-cell tumor of the pubic bone: A case report. Int J Orthop Surg 2009;15:1148 It typically presents in adults between age of 20 to 50 with localized swelling and pain.Blake SM, Gie GA. Large pelvic giant cell tumor: A case report and a review of current treatment modalities. J Arthroplasty 2004;19:1050-4 Females are slightly more affected than males.Sanjay BK, Frassica FJ, Frassica DA. Treatment of giant-cell tumor of the pelvis. J Bone Joint Surg Am 1993;75:1466-75

Average size of the tumor in this region is 9.5 cm.Sanjay BK, Frassica FJ, Frassica DA. Treatment of giant-cell tumor of the pelvis. J Bone Joint Surg Am 1993;75:1466-75

There are different modalities of treatment of pelvic GCT. Radiotherapy has high rate of recurrence (44%) and risk of soft tissue sarcomas (12%).Leggon RE, Zlotecki R, Reith J. Giant Cell Tumor of the pelvis and sacrum. Clin Orthop Relat Res 2004;423:196-207 Thus treatment should be essentially surgical which includes surgical excision. Excision can be extralesional which achieves 90% local tumor control but poor functional outcome Gitelis S, Mallin BA, Piasecki P. Intralesional excision compared with en bloc resection of giant cell tumors of bone. J Bone Joint Surg 1993;17:1648-55 or it can be intralesional which has 90% local recurrence rate with good functional outcome.Bloodgood JC. The conservative treatment of giant cell sarcoma, with the study of bone transplantation. Ann Surg 1912;56:210-39

Massive GCT of pelvis, which is static, not amenable to excision and presenting with mechanical symptoms, can be managed by de-bulking the portion of tumor responsible for mechanical symptoms. And patients need to be followed for local invasion or metastasis.Ali N, Bhat A, Muzzafar K, Bhat SA. Giant 'giant cell tumor' of pelvis. J Sci Soc 2012;39:98-9

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