Feasibility Study of Huangqi Yangyuan Formula for Capecitabine-Induced Adverse Reactions in Advanced Colorectal Cancer

This is a single-center, prospective, open-label, single-arm feasibility study. Thirty-five patients with stage IIIB-IV colorectal adenocarcinoma undergoing capecitabine monotherapy will be enrolled. All participants will receive oral capecitabine (1250 mg/m2, twice daily, 14 days on/7 days off, 21-day cycle, up to 8 cycles) combined with Huangqi Yangyuan Formula (a Chinese herbal decoction, 150 mL twice daily). The primary objective is to evaluate the completion rate of standardized capecitabine chemotherapy at 4 and 8 cycles. Secondary outcomes include chemotherapy-related adverse events (CTCAE v5.0), quality of life (EORTC QLQ-C30), traditional Chinese medicine constitution scores (BCQ), disease-free survival at 3-month follow-up, peripheral blood T-lymphocyte subsets, and safety laboratory indicators.

Inclusion Criteria: * 1\. Aged 18-80 years. * 2\. Histologically confirmed stage IIIB-IV colorectal adenocarcinoma. * 3\. Eligible for planned or ongoing capecitabine monotherapy. * 4\. Expected survival ≥ 6 months. * 5\. ECOG performance status 0-2. * 6\. Baseline bone marrow, hepatic, and renal function adequate for chemotherapy. * 7\. Able to comply with oral medication, scheduled visits, and quality-of-life assessments. * 8\. Willing to provide written informed consent. Exclusion Criteria: * 1\. Pregnant or breastfeeding women; * 2\. History of other systemic malignancies or gastrointestinal in situ cancer within the past 5 years; * 3\. Presence of severe underlying organic diseases affecting the heart, liver, kidneys, respiratory system, or hematopoietic system; * 4\. Persistent severe diarrhea, hand-foot ulcers, or severe malnutrition at baseline that precludes tolerance of chemotherapy; * 5\. Consciousness disorders or psychiatric conditions preventing independent completion of scale assessments and follow-up; * 6\. Known allergy to any ingredient in Huangqi Yangyuan Formula or capecitabine; * 7\. Regular use of anti-tumor Chinese patent medicines, traditional Chinese herbal decoctions, long-term acupuncture/moxibustion for cancer treatment, or anti-cancer dietary supplements within the 2 weeks prior to enrollment, making washout period unfeasible; * 8\. Receipt of radiation therapy, other chemotherapy drugs, targeted therapy, or immunotherapy within the month prior to enrollment; * 9\. Patients currently undergoing double-agent chemotherapy or immunotherapy; * 10\. Refusal to discontinue other anti-cancer traditional Chinese medicine interventions or inability to truthfully report concomitant medications.