Abstract:

Locally advanced rectal cancer (LARC) is defined as a tumour that has invaded the entire bowel wall and may have spread to adjacent tissues or lymph nodes, but has not yet developed distant metastasis.The goals of treatment for LARC are to reduce local recurrence, improve anal retention, and reduce the risk of distant metastasis.Currently, the standard treatment options for LARC mainly include neoadjuvant radiotherapy (nCRT), total mesorectal excision (TME), and adjuvant chemotherapy.Although nCRT and TME have significantly reduced the rate of local recurrence, distant metastasis and low overall pathological complete remission (pCR) rates remain major challenges.In recent years, immunotherapy, especially immune checkpoint inhibitors (e.g., PD-1/PD-L1 inhibitors), has shown significant promise in cancer treatment.Studies have shown that the combination of immunotherapy and nCRT can significantly increase the pCR rate and clinical complete remission (cCR) rate, and enhance anal retention, especially for microsatellite-stabilised (MSS) patients who are usually insensitive to single immunotherapy.In this paper, we will discuss the issues related to neoadjuvant radiotherapy combined with immunotherapy in locally progressive rectal cancer.

Key words: Locally Advanced Rectal Cancer, Neoadjuvant Chemoradiotherapy, Immunotherapy