Comparable survival for young rectal cancer patients, despite unfavourable morphology and more advanced-stage disease

Young patients with rectal cancer tend to present with more advanced-stage disease and unfavourable tumour morphology. The effects of these tumour characteristics on survival in this particular patient group are unclear.

Population-based data from the Netherlands Cancer Registry (NCR) were used. Data from patients diagnosed with rectal cancer between 1989 and 2010 were selected. Younger patients (⩽ 40 years) were compared with middle-aged patients (41-70 years) with respect to disease stage, tumour characteristics, treatment and outcomes. Patients aged older than 70 years were excluded. Relative excess risk (RER) models were used to perform uni- and multivariate survival analyses.

A total of 37.056 patients were included (⩽ 40 years n = 1.102). Compared with middle-aged patients, young patients were more likely to have stage III (33.8% versus 27.8%) and stage IV (24.3% versus 19.6%) disease (p < 0.001). Young patients also presented more frequently with mucinous tumours (10.8% versus 9.0%), signet cell carcinomas (2.6% versus 0.6%) and poorly differentiated tumours (16.6% versus 12.3%) (p = 0.001). The treatment of stage I-III patients did not differ between the two groups, except regarding adjuvant chemotherapy, which was more often given to young patients (24.3% versus 14.4%, p < 0.001). Young age was a prognostic factor for better survival in stage I-III patients (RER 0.82 CI 0.71-0.94). Adjuvant chemotherapy was associated with improved survival in stage I-III patients (RER 0.76, 95%CI 0.70-0.83). In an exploratory analysis, adjuvant chemotherapy in young stage III and pN1 patients was associated with improved survival.

Young patients present with more advanced disease and have more unfavourable tumour characteristics compared with middle-aged patients. Despite these characteristics, survival rates are equal, and young age is a prognostic factor for better survival. Although the use of adjuvant chemotherapy is controversial, a positive correlation with survival was found in this study.