Epidemiologic trend of mobile spine and sacrum chordoma: A National population-based study

Introduction: Chordoma is a rare sarcoma of the axial skeleton. The incidence of this tumor is different between races. To understand the epidemiologic characteristic and due to rarity of this pathology, large number of cases should be evaluated through national data registries. Materials and Methods: All pathologically confirmed cases of chordoma were derived from the Iran National Cancer Registry. Descriptive analysis was performed to extract age-standardized and age-specific incidence rates. Data regarding tumor location and chordoma subtypes were derived and analyzed. Results: One hundred twenty-two cases of chordoma including 80 male and 42 female were identified. One hundred seven cases of nonotherwise specified chordoma, 14 chondroid chordoma, and one dedifferentiated chordoma were detected. The age-standardized incidence rate (ASIR) of chordoma was 0.28. Chordoma of the sacrum composed 67.2% of cases. The mean survival time was 4.5 years. Conclusion: Epidemiology characteristic of chordoma in Iran is similar to other studies; however, the total ASIR was lower and the incidence in sacrum is nearly twice respect to the mobile spine. While men affected by sacral chordoma in relatively older age, the female patients had higher mean age in case of mobile spine involvement. The survival rate of chordoma is significantly lower in comparison with other studies.