Early-onset well-differentiated neuroendocrine neoplasms see uneven rise in last two decades

The past two decades have seen a disproportionate increase in cases of early-onset, well-differentiated neuroendocrine neoplasms (age 20‒34 years) compared with other age groups, driven primarily by midgut tumours, according to a recent study.

The authors accessed the Surveillance, Epidemiology, and End Results (SEER)-18 database to review patients with well-differentiated lung or digestive tract neuroendocrine neoplasms diagnosed from 2000 to 2018. They calculated annual percent changes (APCs) for the three disease subsites (ie, foregut, midgut, and hindgut) stratified by age group.

Differences in overall survival (OS) across age groups were assessed using Kaplan-Meier survival estimates/log-rank testing. Finally, factors affecting OS and cancer-specific survival were examined through multivariable Cox regression analyses.

The greatest APC was observed in patients with early-onset disease (age 20‒34 years: 9.7; 35‒49 years: 5.4; ≥50 years: 4.1) throughout the study period. Stratifying APCs by disease subsite showed that the main driver of such difference was midgut tumours (20‒34 years: 19.2; 35‒49 years: 8.4; ≥50 years: 3.8).

Multivariate analysis revealed the following variables contributing to a higher risk of all-cause death (worse OS): male sex (hazard ratio [HR], 1.27, 95 percent confidence interval [CI], 1.22‒1.31), African American race (HR vs White race, 1.20, 95 percent CI, 1.15‒1.26), nonhindgut primary (HR foregut vs hindgut primary, 2.02, 95 percent CI, 1.91‒2.13; HR midgut vs hindgut primary, 2.09, 95 percent CI, 1.95‒2.24), distant disease (HR vs regional disease, 2.06, 95 percent CI, 1.96‒2.18), no surgery to the primary (HR, 2.34, 95 percent CI, 2.24‒2.46), and older age (HR, 5.80, 95 percent CI, 4.87‒6.91).