Preoperative Chemoradiotherapy Versus Upfront Surgery for Early-Onset Clinical Stage II–III Rectal Cancer: A Multicenter Asian Registry Study

Rectal cancer is a disease where abnormal cells grow in the last section of the large intestine, the part closest to the exit of the body. When doctors find this cancer early, before it has spread far, they often have a choice about how to treat it. One path is to operate immediately to remove the tumor. The other path is to give the patient a combination of radiation and strong medicines, known as chemotherapy, before the surgery. This pre-treatment aims to shrink the tumor and kill hidden cells, theoretically making the operation easier and the outcome better. For many years, the standard approach for certain stages of this cancer has been to use that pre-treatment first. However, a specific group of patients has raised a question: does this extra step actually help young people? Patients who develop this disease before they turn fifty often have tumors that behave differently than those in older adults, and doctors have wondered if the standard heavy treatment is truly necessary for them or if it might even cause more harm than good without adding real benefit.

A team of researchers from eleven hospitals across East and Southeast Asia decided to look closely at this question. They gathered medical records from 415 young adults, aged between 18 and 49, who were diagnosed with stage II or stage III rectal cancer between 2013 and 2023. These patients had all undergone surgery to remove their cancer. The researchers split the group into two categories based on what happened before the operation: 270 patients had gone straight to surgery, while 145 patients had received the preoperative chemoradiotherapy first. To make a fair comparison between these two groups, the scientists used a statistical method that balanced the differences in their medical histories, ensuring that the comparison focused on the treatment itself rather than other factors like tumor size or patient health. They then watched these patients for a median of 4.17 years to see how long they lived without the cancer returning and how long they lived overall.

The results of this large study challenged the assumption that pre-treatment always leads to better survival for young patients. When the researchers compared the two groups, they found that the patients who received radiation and chemotherapy before surgery did not live longer or stay cancer-free for a longer time than those who went straight to the operating room. In fact, the data showed a slight trend, though not a statistically proven one, suggesting that the pre-treatment group might have had slightly lower survival rates, but the difference was small enough that it could have happened by chance. Specifically, about 58.6% of the patients who had pre-treatment were still alive and cancer-free five years after their surgery, compared to 66.4% of those who had upfront surgery. Similarly, the overall survival rate at five years was 84.9% for the pre-treated group and 89.8% for the surgery-only group. The number of patients whose cancer came back in the same area was very similar for both groups, with nine cases in the surgery-only group and eight in the pre-treatment group.

The study concludes that for these young patients who underwent successful surgery, adding radiation and chemotherapy beforehand did not significantly improve their chances of survival. The researchers are careful to note that this does not prove the two approaches are exactly the same, but rather that the extra treatment did not show a clear benefit in this specific group. The findings suggest that the decision to use preoperative chemoradiotherapy should not be automatic. Instead, doctors should look closely at the specific risks of the tumor in the local area before deciding on a treatment plan. While this study provides a clear picture of survival outcomes, the authors point out that future research is needed to understand how these treatments affect the patients' daily lives and whether they can complete the full course of therapy without severe side effects. For now, the data indicates that for early-onset rectal cancer in this region, the standard heavy pre-treatment may not be the necessary first step for everyone.