Abdominal pain and bloody stool may be important warning signs of early-onset colorectal cancer

In a recently published review, JAMA Network OpenThe team of researchers discussed common presenting symptoms and warning signs seen in patients with early-onset colorectal cancer, the association between these signs and the risk of early-onset colorectal cancer, and the differences in the time that elapses between the onset of these signs and diagnosis.

study: Warning Signs and Symptoms in Patients with Early-Onset Colorectal CancerImage credit: Jo Panuwat D / Shutterstock

background

Recent trends show a decline in the incidence of colorectal cancer among older adults, but the incidence of early-onset colorectal cancer diagnosed under age 50 is rapidly increasing. Studies suggest that while global trends are similar, the incidence of early-onset colorectal cancer in the United States could increase by 140% by 2030.

These alarming predictions have led to updated colon cancer screening guidelines, with screening for those who may be at average risk for colon cancer beginning at age 45. Furthermore, early detection is a priority, as patients' chances of survival are significantly increased if colon cancer is diagnosed and treated early.

Given that diagnostic delays may occur for a variety of reasons, including clinicians' lack of knowledge about common symptoms of CRC, patients downplaying the severity of symptoms, or failing to recognize common warning signs, it is essential to gain a better understanding of the common symptoms and warning signs of early-onset CRC.

About the Research

This study aimed to answer three questions through a systematic review and meta-analysis of studies on early-onset CRC. First, we aimed to identify the most common symptoms and signs in patients with early-onset CRC, second, to understand the association between these symptoms and signs and the risk of early-onset CRC, and finally, to investigate the time period between the first appearance of these symptoms and the diagnosis of early-onset CRC.

The review included studies that reported on symptoms, signs, or time of diagnosis of non-hereditary colorectal cancer in individuals under the age of 50. However, studies with fewer than 15 patients or in which the majority of patients were under the age of 18 were excluded.

Relevant information was extracted from studies, including the proportion of patients with early-onset CRC who presented with each symptom or sign, estimates of the association between symptoms and risk of early-onset CRC, and patient reports and medical records of the time elapsed between symptom presentation and diagnosis.

Stratified analyses were performed to assess whether variations in risk estimates were based on factors such as age group, geographic location, risk of bias, etc. The researchers assessed the heterogeneity of risk estimates across different studies and further stratified according to study characteristics.

Researchers reported symptoms and signs that were described in at least three studies and risk estimates for early-onset CRC. Reporting of time to diagnosis, defined as the period from the date of symptom or sign onset to the date of diagnosis, was also stratified by type of data source, as measurements varied across studies.

result

The results showed that more than 50% of early-onset colon cancer patients abdominal pain Symptoms include hematochezia, or blood in the stool, and changes in bowel habits were seen in 25% of patients.

Having bloody stool was associated with a 5- to 54-fold increased risk of colon cancer, and abdominal pain was associated with a 1.3- to 6-fold increased likelihood of colon cancer. Furthermore, they found that a delay of 4 to 6 months between the first appearance of one of the symptoms and diagnosis of the disease was common.

While some studies have reported that younger patients with CRC take longer to be diagnosed than middle-aged patients, other studies have argued that the reason younger patients are diagnosed with more advanced stages of CRC at presentation compared to older patients may not be due to a delay in diagnosis, but rather to other genetic and biological factors.

The researchers believe these findings highlight the need for clinicians to consider early-onset CRC in their differential diagnosis when patients present with warning signs such as bloody stools or abdominal pain. Additional tests such as colonoscopy, ultrasound, and computed tomography should be considered to confirm or exclude early-onset CRC in the differential diagnosis.

Conclusion

Overall, the findings showed that symptoms such as abdominal pain and bloody stools were present in more than 50 percent of patients with early-stage colorectal cancer, and a quarter of patients experienced changes in bowel habits.

The researchers believe that when these warning signs are present, early-onset CRC should be considered part of the differential diagnosis and that clinicians should perform additional testing to confirm or exclude early-onset CRC and avoid further delays in diagnosis.