Tag Archive for: rectal cancer

By Parker Lynch

In a recent study conducted in Korea, it was found that higher levels of alcohol consumption increase an individual’s risk of early-onset colorectal cancer (early-onset CRC), specifically distal colon and rectal cancers. Using data from the Korean National Health Insurance Service, investigators retrospectively compared the drinking habits of 5.7 million Korean adults (all younger than fifty years old) and their corresponding CRC risk. 

The study’s population was split into four groups (after being adjusted for age, sex, smoking status, exercise, income, and comorbidities): 

  1. Nondrinkers (no alcohol consumption)
  2. Light drinkers 
  3. Moderate drinkers 
  4. Heavy drinkers.

During the mean follow-up period of 7.4 years, there were 8,314 cases of early-onset CRC overall. When being compared with the light drinking group, those in both the moderate and heavy drinking categories had a significantly higher CRC risk, though the most intense discrepancy was demonstrated among men. Among men, there was a:

  • 26% increase in risk of distal colon cancer 
  • 17% higher risk of rectal cancer 
  • 29% higher risk of unspecified colon cancer when comparing the heavy versus light drinking group. 

Among women, there was a: 

  • 47% increased risk of distal colon cancer among moderate drinkers 
  • 14% reduced risk of rectal cancer among the light drinkers. 

Overall, this study provides strong evidence that higher levels of alcohol consumption can increase one’s risk of early-onset CRC. 

What Are the Implications of These Findings?

Although the aforementioned study is limited to generalizability among Korean citizens, its findings are still very important to consider when looking at the diverse American population.

In fact, the dangers of excessive alcohol use and its connection to increased CRC risk are not something that American researchers or doctors are unfamiliar with. In an article published by the Ocean Endosurgery Center, less than half of Americans are even aware that alcohol consumption has an impact on cancer risk at all. Additionally, the official Dietary Guidelines for Americans strongly suggests that men should not consume more than two alcoholic drinks per day, while women should drink no more than one. In terms of what is best for an individual’s health, researchers have determined that people really should only be drinking on special occasions.

Many Americans don’t know this information, and there must be a push for increased education and awareness so that people are able to make informed decisions about their own health. Regardless of whether or not people choose to drink after discovering the risks involved, everyone deserves to know the implications of potential lifestyle choices. 

 

Parker Lynch is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

 Photo credit: CHUTTERSNAP on Unsplash

Locally advanced rectal cancer may involve multistep neoadjuvant therapy to shrink the tumor before the main treatment, which is often surgery. Although this approach results in a complete pathological response in up to 25% of patients, it involves the risk of complications and toxic effects, including bowel, urinary, and sexual dysfunction; infertility; and altered quality of life in a significant number of patients. A new study, published in the New England Journal of Medicine, has found that patients with mismatch repair-deficient, locally advanced rectal cancer can be effectively treated with neoadjuvant programmed death-1 (PD-1) blockade.  

Approximately 5-10% of rectal adenocarcinomas are attributed to mismatch-repair deficiency, and this subset of tumors respond poorly to standard chemotherapy treatments. Immune checkpoint blockade could be an effective treatment option for this subset of patients. PD-1 elicits an immune checkpoint response of T-cells, allowing tumor cells to bypass the immune system defense, as well as resist the effects of chemotherapy. To test this hypothesis, researchers at Memorial Sloan Kettering Cancer Center and Yale University School of Medicine conducted a phase 2 investigation to analyze the overall response and frequency of sustained clinical complete response to neoadjuvant treatment with a PD-1 inhibitor, dostarlimab. 

PD-1 Blockade Eliminated Rectal Tumors

Of the sixteen patients enrolled in the study, twelve were enrolled for more than six months and completed nine cycles of dostarlimab. The resulting clinical complete response was measured by a combination of rectal MRI, visual endoscopic inspection, and digital rectal examination in twelve patients who had at least six months of follow-up. Endoscopic biopsies were performed at baseline and during visual inspection of tumor response at six weeks, three months, and 6 months, and then every four months thereafter. Serial FDG-PET scans to evaluate tumor eradication presented similar results to that seen with pathological examination and genomic analysis of the evolution of tumor eradication. 

The elimination of tumors after six months of therapy with PD-1 blockade allowed Dr. Cercek and her team to be able to omit both chemoradiotherapy and surgery and to move forward with observation alone. Single-agent dostarlimab was significantly influential in treating mismatch repair-deficient, locally advanced rectal cancer. It provided a clinical complete response in all 12 patients who completed treatment to date. 

Surgery and radiation can permanently impact fertility, sexual health, and bowel and bladder function. With the rise in incidence of rectal cancer among young patients of child-bearing age, anti-PD-1 antibodies can be a good alternative to chemoradiotherapy and surgery and may specifically benefit this cohort of patients. Dostarlimab promotes a refined approach toward treatment that can significantly improve the quality of life of patients, especially younger patients who may not yet have started a family. These findings also encourage the potential for using PD-1 inhibitors in the treatment of other mismatch repair-deficient tumors, such as localized pancreatic, gastric, and prostate cancers.

 

Sahar Alam is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.