Non Metastatic Rectal Cancer

Rectal cancer care is increasingly complex and may include systemic therapy, radiation therapy, surgery, or nonoperative watch-and-wait surveillance. These treatments can have both short- and long-term effects on bowel, urinary, sexual, and stoma-related function. Prior studies have often assessed quality of life and treatment decision experiences at a single time point or after one type of treatment, resulting in limited information about how patients' experiences change throughout their course of care. This study will evaluate health-related quality of life and experiences with treatment decisions among patients with non-metastatic rectal cancer using validated patient-reported outcome measures over the course of treatment.

This prospective observational, non-therapeutic study for patients with T3, T4, or node positive rectal cancer eligible to undergo total neoadjuvant therapy. This research study involves the collection of data and biospecimens (blood and tissue) to see if the presence of circulating tumor DNA (genetic material) ctDNA will help monitor rectal cancer more closely and potentially detect a recurrence before routine scans, performed per standard of care C2i Genomics, a biotechnology company, and the Spier Foundation are supporting this research study by providing funding for the study.

This is a multicenter, prospective, phase II study evaluating total neoadjuvant therapy (TNT) consisting of short-course radiotherapy (SCRT; 5×5 Gy) followed by QL1706 (a bifunctional MabPair antibody targeting PD-1 and CTLA-4, code name only) plus mFOLFOX6 chemotherapy in patients with locally advanced rectal cancer (LARC) with proficient mismatch repair/microsatellite-stable (pMMR/MSS) biology. Patients with pMMR/MSS disease derive limited benefit from immune checkpoint inhibition alone. Preclinical and clinical evidence suggests that SCRT and oxaliplatin-based chemotherapy can enhance antitumor immunity (e.g., antigen release, T-cell infiltration), providing a biological rationale for combining QL1706 with SCRT-primed TNT. Eligible adults with cT3-4 and/or N+ mid-to-low rectal adenocarcinoma (without distant metastasis), confirmed pMMR/MSS, and ECOG 0-1 will receive: SCRT (total 25 Gy over 5 fractions), then several cycles of QL1706 plus mFOLFOX6 as neoadjuvant systemic therapy. Definitive total mesorectal excision (TME) is planned per multidisciplinary assessment; a watch-and-wait approach may be considered for patients achieving a stringent clinical complete response per institutional criteria. Standard perioperative care and postoperative follow-up will be performed. Primary endpoint is pathologic complete response (pCR, ypT0N0) rate at surgery. Key secondary endpoints include: clinical complete response (cCR) rate, major pathologic response rate, R0 resection rate, tumor downstaging, radiologic response, disease-free survival (DFS), overall survival (OS), organ preservation rate (for patients managed non-operatively), surgical morbidity, and safety/tolerability (CTCAE v5.0). Exploratory endpoints include correlations between efficacy and baseline clinicopathologic features; optional translational analyses may investigate immune-inflammation markers related to response and resistance. This trial aims to determine whether SCRT-primed QL1706 plus mFOLFOX6 TNT can improve tumor eradication and organ preservation while maintaining acceptable safety in pMMR/MSS LARC-a population with unmet need for effective immunotherapy-based strategies.