Incidence and Management of Primary Malignant Small Bowel Cancers: A Well-defined French Population Study

Abstract

Few data are available from population-based statistics on small bowel cancers. The aim of this study was to report on their incidence and management. Data were obtained from the population-based Digestive Cancer Registry of Burgundy over a 26-yr period. Incidence rates were calculated by gender, age group, histological type, and 5-yr period. Treatment and stage at diagnosis were investigated. Prognosis was determined using crude and relative survival rates. A multivariate relative survival analysis was performed. Age-standardized incidence rates were 1.2/100,000 inhabitants for men and 0.8/100,000 inhabitants for women. The mean 5-yr variation in incidence were, respectively, +46.7% (P < 0.01) and + 53.2% (P < 0.05). There were four main histological types: adenocarcinoma (40.4%), malignant endocrine tumors (30.5%), lymphoma (20.1%), and sarcoma (9.0%). Resection for cure was performed in 56.6% of the cases. Cancer was not extending beyond the organ in 33.2% of the cases, was associated with lymph node metastasis in 32.1%, and with distant metastasis or unresectability in 34.7%. The 5-yr relative survival rate was 37.4%. It varied between 56.8% for endocrine tumors and 17.8% for sarcoma. In the multivariate analysis, age, histology, and stage at diagnosis significantly influenced the prognosis. Small bowel cancers represent a heterogeneous group of rare tumors. Prognosis at a population level is worse than in hospital series. In the short term, new therapeutic possibilities represent the best way to improve prognosis.