Pain in abdomen, diarrhea, rectal bleeding and iron deficiency anemia may be linked to increased risk of colorectal cancer (CRC) in adults younger than 50 years of age, according to a new study of more than 5000 cases of early-onset CRC published May 4, 2023 in the Journal of the National Cancer Institute.1 In many patients, these symptoms had been present for up to two years before they were diagnosed with the cancer.

In this study, the researchers examined data of 5075 newly diagnosed cases of early-onset CRC sourced from commercial insurance databases in the United States between 2006 and 2015. Through this, the researchers aimed to identify “warning signs” that were suggestive of colorectal cancer between 3 months and 2 years preceding the day of diagnosis. For this, they evaluated 17 pre-specified signs and symptoms.

The risk of CRC in patients younger than 50 years of age was found to be associated with four signs and symptoms namely abdominal pain, rectal bleeding, diarrhea and iron deficiency anemia with odds ratios ranging from 1.34 to 5.13. Having one of these doubled their risk of developing the cancer with OR of 1.94. Presence of two signs and symptoms increased the risk nearly four times (OR 3.59), whereas the risk increased by nearly 7-folds among those having three or more of these signs and symptoms with OR of 6.52.

The first sign or symptom appeared between 3 months to 2 years before diagnosis in 19.3% cases with a median diagnostic interval of 8.7 months. In half of the patients, the first sign or symptom occurred within 3 months of diagnosis with a median diagnostic interval of 0.53 month.

This study has identified four signs and symptoms that could be indicative of increased risk of CRC. Their presence should not be ignored, especially if persistent. Early recognition of these potential red flags in younger adults may facilitate “early detection and timely diagnosis of early-onset CRC”. Rectal bleeding and iron-deficiency anemia in particular pointed to a need for timely endoscopy and follow-up, according to a press release from the Washington University School of Medicine in St. Louis in the US.2 A healthy lifestyle and undergoing routine screening for CRC when recommended may help lower the risk.

References

1. Fritz CDL, et al. Red-flag signs and symptoms for earlier diagnosis of early-onset colorectal cancer. J Natl Cancer Inst. 2023 May 4;djad068. doi: 10.1093/jnci/djad068.
2. https://www.eurekalert.org/news-releases/988066. May 4, 2023. Accessed on May 15, 2023.