Adenocarcinoma of the Rectum

This trial examines colorectal cancer incidence in participants with 1 to 2 non-advanced adenomas randomized to surveillance colonoscopy at 10 years compared to participants randomized to surveillance colonoscopy at 5 and 10 years.

The purpose of the study is to learn more about how the body responds to standard treatment (chemoradiation and chemotherapy). The study will use the results of testing down on participants' blook, tissue, and scans to learn more about how people with rectal cancer respond to chemoradiation and chemotherapy treatment and if it is useful for predicting whether a person's cancer get better, gets worse, or stats the same after treatment.

The study researchers believe that a combination of the drugs trastuzumab and tucatinib, given with standard chemotherapy (capecitabine and oxaliplatin/FOLFOX), may help participants with rectal cancer.

The purpose of this research study is to determine whether testing of stool for a panel of markers will enable us to detect polyps and cancer compared to standard testing.

The purpose of this study is to study the way radioembolization works by collecting biopsy samples of participants' tumors after the procedure. This research may improve the way that radioembolization is performed, which could help people whose cancer has spread to the liver. The research may also provide information about how tumors respond to radioembolization.

This study compares two standard radiotherapy approaches (short-course vs. long-course) given before surgery in patients with locally advanced rectal cancer. The goal is to see which treatment is more effective and better tolerated.

Any patient with a suspected primary adenocarcinoma of the colon, sigmoid or rectum undergoing surgery are eligible. The date of surgery must be known prior to registration. This trial aims to determine if image mapping techniques can improve the concordance between imaging and pathology detection of tumour deposits. Lymph nodes and tumour deposits will be identified on pre-operative scans and mapped by radiologists then shared with pathologists prior to processing the resected specimen. Patients will be managed at their local hospital with standard follow-up. Patients will be followed up for 5 years.