Unraveling the Etiology of Early-Onset Colorectal Cancer

Individualised prediction of chemotherapy benefit in early-onset colorectal cancer

PURPOSES

Whether patients with early-onset colorectal cancer (EOCRC) receive chemotherapy has been controversial, so our study aimed to screen patients with EOCRC who benefit from chemotherapy.

METHODS

A total of 2166 EOCRC patients were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Patients were divided into chemotherapy and non-chemotherapy groups, propensity score matching (PSM) was performed to balance the differences between the groups, and the Kaplan-Meier method was used to calculate the cancer-specific survival (CSS) of EOCRC patients. Multifactorial COX regression analysis was used to identify independent prognostic factors for CSS and to construct a nomogram for predicting CSS in EOCRC patients. The overall risk score was calculated based on Nomogram, and EOCRC patients were classified into high-risk and low-risk groups to assess further chemotherapy's therapeutic effect on patients with different risk stratification.

RESULTS

Before PSM, patients in the chemotherapy group had poorer CSS (p < 0.001). After PSM, there was no significant difference in patient CSS between the two groups (p = 0.057). Independent prognostic factors (Race, Grade, Pathology, AJCC.N, AJCC.M, CEA, Marital. Status) were screened according to multifactorial COX regression analyses and included in the Nomogram predicting CSS in EOCRC patients. A risk stratification system for EOCRC patients was further developed, and the results showed that chemotherapy had no significant effect on CSS in the low-risk group of patients, but in the high-risk group, chemotherapy significantly improved CSS in EOCRC patients.

CONCLUSIONS

We developed a clinical risk model by combining different risk factors, which can accurately screen those with high-risk EOCRC for benefit from chemotherapy. For low-risk EOCRC patients, our results did not observe a better survival benefit from chemotherapy, and more prospective studies are needed in the future to prove our conclusions.

Colorectal Cancer: Epidemiology, Risk Factors, and Prevention

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer mortality worldwide. There are disparities in the epidemiology of CRC across different populations, most probably due to differences in exposure to lifestyle and environmental factors related to CRC. Prevention is the most effective method for controlling CRC. Primary prevention includes determining and avoiding modifiable risk factors (e.g., alcohol consumption, smoking, and dietary factors) as well as increasing protective factors (e.g., physical activity, aspirin). Further studies, especially randomized, controlled trials, are needed to clarify the association between CRC incidence and exposure to different risk factors or protective factors. Detection and removal of precancerous colorectal lesions is also an effective strategy for controlling CRC. Multiple factors, both at the individual and community levels (e.g., patient preferences, availability of screening modalities, costs, benefits, and adverse events), should be taken into account in designing and implementing CRC screening programs. Health policymakers should consider the best decision in identifying the starting age and selection of the most effective screening strategies for the target population. This review aims to present updated evidence on the epidemiology, risk factors, and prevention of CRC.

Significant Rise of Colorectal Cancer Incidence in Younger Adults and Strong Determinants: 30 Years Longitudinal Differences between under and over 50s

(1) Background: There is evidence in the recent literature that the incidence patterns of colorectal cancer (CRC) have changed considerably over the years, tending to rise rapidly in individuals under 50 years old compared with those over 50 years. The current study aimed to assess the incidence of CRC in Crete from 1992−2021 and compare them among younger and older adults. (2) Methods: Data on malignant neoplasms of colon, rectosigmoid junction, and rectum have been extracted from the database of the Regional Cancer Registry of Crete. (3) Results: The number of these cases for the period 1992−2021 was 3857 (n = 2895 colon and n = 962 rectum). The mean age-specific incidence rate (ASpIR/100,000/year) of colon cancer patients <50 years was 7.2 (95% CI 5.1−9.7), while for patients ≥50 years the ASpIR was 149 (95% CI 146.2−153.4). ASpIR presented a 29.6% increase from 2001 to 2011 in the age group of 20−34 years and further increase is expected from 2022−2030 (projected change, 42.8%). The main risk factors were the pack years (p = 0.01), alcohol consumption (0.02), and farmer occupation (0.04), especially during 2012−2021. (4) Conclusions: We confirmed an increased incidence of CRC in young adults <50 in a European population with low cancer incidence in the past and a worrisome prediction for the near future. The observed trends clearly indicate that starting CRC screening at an earlier age may be essential.

Advances in Understanding Early-Onset Colorectal Cancer

Since the 1990s, the incidence of early-onset colorectal cancer (at <50 years of age) in the US has increased by more than 50%; similar increases have also been observed internationally. These increases are found particularly among individuals born during and after the 1960s, raising the possibility that the increased rates of early-onset colorectal cancer are attributable to changes in risk-factor patterns throughout successive generations. The reasons for these alarming epidemiologic patterns for early-onset colorectal cancer worldwide are only recently being investigated and major gaps in our knowledge remain. In the current issue of this journal, Arif and colleagues differentiated characteristics and outcomes of early-onset colorectal cancer in patients with the predisposing conditions of inflammatory bowel disease or hereditary genetic syndromes, compared with patients who have sporadic disease. Also, in this issue, Schumacher and colleagues investigated risk factors for early-onset colorectal adenocarcinoma in a nested case-control study among Kaiser Permanente Southern California (KPSC) health plan members. The research presented on characteristics and outcomes points to the importance of sporadic disease in the rise of early-onset colorectal cancer, while the research presented on risk factors points to the importance of obesity as a potential explanatory factor for this rise.See related articles by Arif et al., p. 1785 and by Schumacher et al., p. 1792.