Age as a Predictor of Overall Survival in Colorectal Cancer

The diagnosis of colorectal cancer (CRC) at early ages has become a challenging trend for oncology due to high rates of mortality worldwide. The correlation of clinical features with young-age prognosis in CRC remains unclear. Therefore, we aimed to describe the clinicopathological features and their impact on the overall survival of young Mexican adults diagnosed with CRC treated in the National Cancer Institute.

This was a retrospective, observational study. The included patients were treated at the National Cancer Institute between 2004 and 2020. The statistical analyses comprised the X² and t tests, Kaplan-Meier, log rank, and Cox regression. Statistical significances were assessed when p was bilaterally < 0.05.

A total of 3652 patients diagnosed with CRC attended the National Cancer Institute. Cases of early onset of CRC increased over the 16 years under study, with significant differences between the median age, from 57 in 2004 to 55 years old in 2020 (F = 5.49; gl: 12 p = 0.019). For this analysis, the population was divided in three groups: young (≤30 years), adults (31-70), and elderly (>70). The young population was mostly composed of men (62%; (n = 63), (p = 0.020), with high rates of metastatic disease (44%) (p = 0.001) and right-side tumors (57%), (p = 0.046), and with 44% with a moderate grade (p = 0.750). According to the overall survival (OS) analysis, the median OS was 29 months for young, versus 170 months for adult and 56 months for elderly patients (p <0.001, HR 1.53, 95% CI 1.11-2.10). A sub-analysis was performed considering only patients with metastatic disease. The median OS was 12 months for young, versus 17 and 9 months for adults and elderly (p = 0.08, HR 1.27, 95% CI 1.02-1.46).

CRC diagnosis in the young population is increasing due unhealthy lifestyle habits and lack of screening. This population have clinical features of bad prognosis, such as left side, poor grade differentiation, and metastatic disease, precluding prognosis and OS.