A prospective observational study to determine the feasibility of tumor response assessment by circulating tumor DNA (ctDNA) in patients with locally advanced rectal cancer (LARC) undergoing total neoadjuvant therapy (TNT).
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request. ### Instruction: Identify all the mentioned drugs in the given text. Text may or may not contain drug. If they contain more than 1 drug, use ";" as delimiter and join them. ### Input: A prospective observational study to determine the feasibility of tumor response assessment by circulating tumor DNA (ctDNA) in patients with locally advanced rectal cancer (LARC) undergoing total neoadjuvant therapy (TNT). ### Output: 