Population-Based Study of Giant Cell Tumour of the Bone in Sweden

Abstract

ABSTRACT Aim: Giant-cell tumour of the bone (GCTB) is a locally aggressive and histologically benign neoplasm with a less common malignant counterpart. Sources of data on GCTB are sparse, and most published data are from individual case reports or case series. The Swedish Cancer Registry is one of the few national population-based databases that routinely records GCTB; representing a unique source to study the epidemiology of GCTB. The primary goal was to estimate the incidence rate (IR) and mortality rates of GCTB as recorded in the registry. Methods: We identified patients with a GCTB diagnosis in the Swedish Cancer Registry from 1983-2011: benign (ICD-7 196.0-196.9; PAD 741) and malignant (PAD 746). Results were stratified by age at diagnosis, gender, and anatomical lesion location. Mortality was described for patients diagnosed 1997-2011. Results: The cohort included 337 GCTB cases, corresponding to an IR of 1.3 per million persons per year. The majority (n=310) were primary benign (b)GCTB with population IR of 1.2 per million per year. Median age was 34 years (range 10–88) with 54% (n=183) female. Malignant to benign ratio was higher among women 0.095 (16/167) than men 0.077(11/143). Incidence was highest in the 20–29 years age group with an IR of 2.5 per million per year. The most common lesion site for both bGCTB and malignant (m)GCTB was the lower extremity (Table). Overall mortality at 14 years since diagnosis was 9% (n=14) and was higher for pelvic lesions (n=2; 15%). bGCTB mGCTB N Incidence * N Incidence * Age 0–19 43 0.67 2 0.03 20–39 133 1.86 15 0.21 40–59 90 1.31 5 0.07 60+ 44 0.74 5 0.08 Location Axial 33 0.13 2 0.01 Pelvic 19 0.07 4 0.02 Upper extremity 81 0.32 4 0.02 Lower extremity 143 0.56 13 0.05 Non-spec 34 0.13 4 0.02 * per million, per year Conclusions: This population-based, retrospective cohort study confirmed that GCTB is a rare disease in Sweden. Consistent with the published literature, malignant cases were uncommon (8%), peak incidence between 20–39 years, slight predominance in women, and most common lesion location was lower extremity. Further work is ongoing to elucidate risk factors associated with outcomes of patients with GCTB. Disclosure: J. Amelio: JA is employed by and owns stock in Amgen; J. Sandberg: JS is employed at IMS and are consultants for Amgen; R. Hernandez: RH is employed by and own stocks in Amgen; P. Sobocki: PS is employed at IMS and are consultants for Amgen; S. Stryker: SS is employed by and owns stock in Amgen; J. Engellau: JE is a board member of Genovis Inc. He has participated advisory board meetings for Amgen and lectured for Amgen on the topic GCTB; B. Bach: BB is employed by and owns stock in Amgen; A. Liede: AL is employed by and owns stock in Amgen