Two hundred eighty-six cases of parathyroid carcinoma treated in the U.S. between 1985-1995: A National Cancer Data Base report

BACKGROUND. In combination with other Commission on Cancer programs, the National Cancer Data Base (NCDB), a national electronic registry system currently capturing > 60% of incident cancers in the U. S., offers a working example of voluntary, accurate, cost-effective 'outcomes management' on a both a local and national scale. In addition, it is proving to be of particular value in capturing clinical information concerning rare cancers. METHODS. For accession years 1985-1995, the NCDB captured prospectively collected demographic, stage, treatment, and outcome information for a national hospital-based sample of 286 parathyroid carcinoma cases (0.005% of the total NCDB cancer cases). This report describes clinical and demographic features as well as patterns of care and 5-year and 10-year relative survival rates. RESULTS. The NCDB's 10-year accrual of parathyroid carcinoma cases exceeded the cumulative number reported in the English literature though 1991. Gender distribution was equal. The authors were unable to detect any disproportionate clustering by race, income level, or geographic region. Treatment overwhelmingly was surgical. The data from the current study suggest that neither tumor size nor lymph node status are significant prognostic factors. Overall relative survival at 5 years and 10 years was 85.5% and 49.1%, respectively. CONCLUSIONS. At 5 years of follow-up, and possibly beyond, neither tumor size nor lymph node status were found to be significant prognostic factors and basing a staging system on them would be useless. Although complete, en bloc resection of all tumor represents the best opportunity for cure, a substantial proportion of patients fail to receive such treatment. The authors speculate that the rarity of this condition and late intraoperative recognition occasionally prevent optimal treatment.