Incidence, clinical features and possible etiology of early onset (≤40 years) colorectal neoplasms.

The aim of the study was to investigate the clinical features, including survival, of patients with colorectal malignancies developed at a very early age (≤40 years), together with possible factors involved in the pathogenesis of these rare neoplasms. The study took advantage of the existence of a specialized colorectal cancer Registry active from 1984. 57 patients met the criteria of early onset cancer; main epidemiological data, morphology, stage, familial aggregation, possible role of inheritance and survival were analyzed. Despite the relevant increase over time of all registered patients, joiningpoint analysis of crude incidence rate of early onset colorectal neoplasms revealed a certain stability of these tumors (EAPC: 2.4, CI 14-22) with a constant prevalence of the male sex. Stage at diagnosis did not show significant variations between early onset and maturity onset colorectal neoplasms. Hereditary as well as familial cases were significantly (P < 0.005 and 0.03) more frequent among patients with early onset tumors, although in the majority of them no specific etiological factor could be identified. Survival was more favorable in patients with early onset tumors, though this had to be attributed to the higher presence of some histological types in early onset cases. Survival was significantly more favorable for patients of all ages registered in the last decade. Incidence of early onset colorectal cancer was relatively stable between 1984 and 2008. A male preponderance was evident through the registration period. Hereditary and familial cases were significantly more frequent among early onset case. A well defined etiology could be observed in 16% of the cases (versus 2-3% in older individuals). Five-year survival showed a significant improvement over time.