A comparison between two types of radiation therapy in the treatment of rectal cancer

This study compared the effectiveness of two different types of radiation therapy to treat rectal cancer. Researchers suggested that high-dose endorectal brachytherapy (HDEB) is associated with improved tumor response.

The standard treatment for rectal cancer that has spread outside the rectum lining (T3 tumor) is radiation therapy followed by surgery. There are several types of radiation therapy. External beam radiotherapy (EBRT) is the standard radiation therapy. However, it is associated with a high rate of side effects. High dose endorectal brachytherapy (HDEB) uses a radioactive seed implanted in the tumor. It delivers radiation directly to the affected area. It might be a good treatment option because it treats the tumor without affecting other organs.

Prior studies showed that HDEB is associated with less toxicity, shorter treatment duration, and less inflammation. It is still not clear if HDEB is associated with improved tumor response when compared to the standard method in patients with rectal cancer.

This study included 99 patients with T3 rectal cancer. 64 patients (64.6%) underwent HDEB and 35 (35.4%) underwent EBRT before surgery. Patients from the HDEB group had less cancer spread. They were followed up for 38.9 months.

12 (18.8%) patients in the HDEB group and 6 (17.1%) from the EBRT group had complete tumor response (shrinkage). HDEB led to downstaging in 75.1% of patients compared to 57.1% in the EBRT group.

A partial response was seen in 56.2% of the HDEB and in 40% of the EBRT group. However, EBRT was more effective on the lymph nodes (51.4%) compared to HDEB (35.9%). Disease-free survival was better for the HDEB group compared to EBRT.

This study concluded that HDEB might be a safe and effective option to treat patients with T3 rectal cancer before receiving surgery.

This study had a limited number of participants. It also looked at medical records. Further studies are needed for stronger evidence.