Quicksilver II Non-inferiority Randomized Controlled Trial: Direct-to-surgery or Neoadjuvant Chemotherapy and Surgery in Margin-clear Stage II or III Rectal Cancer

Before patients with rectal cancer go for surgery, tests determine tumour stage and if there are cancer cells near the edge of the rectum - if there are no cancer cells near the edge the tumour is called 'margin-clear'. Surgeons operate just outside the 'margin' to best remove all cancer cells. In Canada, patients with stage 2 or 3 cancer are almost always given radiation and chemotherapy before surgery to lower the risk the cancer will return. However, these treatments can cause life-long side effects like poor bowel function or nerve damage in the hands. A small study of patients with margin-clear stage 2 and 3 rectal cancer showed that radiation and chemotherapy is likely not needed before surgery. However, researchers would like to test these findings in a larger trial called "Quicksilver II". Before applying for Quicksilver II funding, the researchers have to show the trial steps are possible. This will be accomplished through a feasibility/pilot trial at several high-volume rectal cancer centres. Patients with margin-clear stage 2 or 3 rectal cancer will be randomized to 'surgery' or 'chemotherapy and surgery'. If the pilot study works and if Quicksilver II is positive, it may change the way patients with margin-clear tumours are treated around the world.