Preoperative sequential short-course radiation therapy and FOLFOX chemotherapy versus long-course chemoradiotherapy for locally advanced rectal cancer: a multicenter, randomized controlled trial (SOLAR trial).

BACKGROUND: Preoperative (chemo)radiotherapy has been widely used as an effective treatment for locally advanced rectal cancer (LARC), leading to a significant reduction in pelvic recurrence rates. Because early administration of intensive chemotherapy for LARC has more advantages than adjuvant chemotherapy, total neoadjuvant therapy (TNT) has been introduced and evaluated to determine whether it can improve tumor response or treatment outcomes. This study aims to investigate whether short-course radiotherapy (SCRT) followed by intensive chemotherapy improves oncologic outcomes compared with traditional preoperative long-course chemoradiotherapy (CRT). METHODS: A multicenter randomized phase II trial involving 364 patients with LARC (cT3-4, cN+, or presence of extramural vascular invasion) will be conducted. Patients will be randomly assigned to the experimental or control arm at a ratio of 1:1. Participants in the experimental arm will receive SCRT (25 Gy in 5 fractions, daily) followed by four cycles of FOLFOX (oxaliplatin, 5-fluorouracil, and folinic acid) as a neoadjuvant treatment, and those in the control arm will receive conventional radiotherapy (45-50.4 Gy in 25-28 fractions, 5 times a week) concurrently with capecitabine or 5-fluorouracil. As a mandatory surgical procedure, total mesorectal excision will be performed 2-5 weeks from the last cycle of chemotherapy in the experimental arm and 6-8 weeks after the last day of radiotherapy in the control arm. The primary endpoint is 3-year disease-free survival, and the secondary endpoints are tumor response, overall survival, toxicities, quality of life, and cost-effectiveness. DISCUSSION: This is the first Korean randomized controlled study comparing SCRT-based TNT with traditional preoperative LC-CRT for LARC. The involvement of experienced colorectal surgeons ensures high-quality surgical resection. SCRT followed by FOLFOX chemotherapy is expected to improve disease-free survival compared with CRT, with potential advantages in tumor response, quality of life, and cost-effectiveness. TRIAL REGISTRATION: This trial is registered at Clinical Research Information under the identifier Service KCT0004874 on April 02, 2020, and at Clinicaltrial.gov under the identifier NCT05673772 on January 06, 2023.

Oncological impact of intraperitoneal chemotherapy after cytoreductive surgery for patients with colorectal peritoneal metastasis: A bi-institutional retrospective analysis.

BACKGROUND AND OBJECTIVES: There is a paucity of evidence on the value of intraperitoneal chemotherapy (IPC) following cytoreductive surgery (CRS) for colorectal peritoneal metastasis. This study aimed to evaluate the association between mitomycin C-IPC and survival outcomes following CRS. METHODS: The institutional databases of two tertiary hospitals were reviewed to identify patients who underwent CRS for colorectal peritoneal metastasis. The outcomes of patients who underwent CRS without IPC were compared with those of patients who underwent CRS plus early postoperative intraperitoneal chemotherapy (EPIC) or CRS plus hyperthermic intraperitoneal chemotherapy (HIPEC). The primary endpoints were cancer-specific survival (CSS), progression-free survival (PFS), and peritoneal PFS (P-PFS). RESULTS: In 149 patients with peritoneal metastasis alone, EPIC and HIPEC use was significantly associated with better CSS, PFS, and P-PFS in the multivariate analysis. CSS was also significantly associated with perioperative systemic chemotherapy. Among 42 patients with both peritoneal and extraperitoneal metastases, CSS was independently related to the completeness of cytoreduction score, location of extraperitoneal metastasis, and grade 3-4 complications. CONCLUSIONS: Mitomycin C-IPC after CRS was associated with better survival outcomes than CRS alone in patients with resectable peritoneal metastasis of colorectal cancer. This study found that IPC had beneficial effects regarding P-PFS in patients with both peritoneal and extraperitoneal metastases.

Initial experience of preoperative short-course radiotherapy followed by oxaliplatin-based consolidation chemotherapy for locally advanced rectal cancer.

PURPOSE: We analyzed the safety and feasibility of preoperative short-course radiotherapy (SCRT) followed by consolidation chemotherapy for patients with locally advanced rectal cancer (LARC). METHODS: From April 2018 to May 2019, 19 patients with LARC were treated with SCRT followed by three cycles of consolidation chemotherapy with leucovorin, fluorouracil, and oxaliplatin (FOLFOX6) before surgery. Adjuvant chemotherapy relied on oxaliplatin. Tumor response, patient compliance, and toxicities were analyzed. RESULTS: The median age was 60 years (range 44-71), and 16 of the patients were male. The median tumor height was 5 cm (range 0-9) from anal verge. All patients received a total dose of 25 Gy in five fractions. The number of cycles of FOLFOX6 before surgery was three in 17, four in one, five in one. Five patients required dose reductions in consolidation chemotherapy. The median interval between initiation of SCRT and surgery was 10.6 weeks (range 8.6-16.4). A pathologic complete response was seen in two patients (11%). Grade III toxicities to the preoperative treatment were seen in five patients (26%): diarrhea in two, a decreased white blood cell count in one, and anemia in two. Postoperative complications arising within 30 days developed in five patients (26%). During the median follow-up period of 20.4 months, there was no tumor recurrence. CONCLUSION: Preoperative SCRT followed by oxaliplatin-based consolidation chemotherapy showed acceptable toxicity and feasibility in patients with LARC. Prospective randomized trials are warranted to verify the efficacy and safety of this treatment strategy compared with conventional long-course concurrent chemoradiotherapy.

Impact of Anatomic Extent of Nodal Metastasis on Adjuvant Chemotherapy Outcomes in Stage III Colon Cancer.

BACKGROUND: An oxaliplatin-based chemotherapy regimen improves the survival outcomes of patients with stage III colon cancer. However, its complications are well-known. OBJECTIVE: The purpose of this study was to distinguish between the survival outcomes of patients who underwent curative resection for stage III colon cancer with oxaliplatin chemotherapy and those who underwent such resection without oxaliplatin chemotherapy. DESIGN: This was a retrospective analytical study based on prospectively collected data. SETTINGS: This study used data on patients who underwent surgery at our hospital between January 2010 and December 2014. PATIENTS: A cohort of 254 consecutive patients who underwent curative resection for stage III colon cancer was included in this study. The patients were divided into 2 groups: patients with isolated pericolic lymph node metastasis (n = 175) and those with extrapericolic lymph node metastasis (n = 79). MAIN OUTCOME MEASURES: Clinicopathologic features and 3-year survival outcomes were analyzed with and without oxaliplatin therapy in the pericolic lymph node group. RESULTS: The pericolic lymph node group showed significantly improved overall survival compared with the extrapericolic lymph node group at a median follow-up of 48.5 months (95.8% vs 77.8%; p < 0.001). In contrast, there was no significant difference in overall survival (99.0% vs 92.0%; p = 0.137) and disease-free survival (89.1% vs 88.2%; p = 0.460) between the oxaliplatin and nonoxaliplatin subgroups of the pericolic lymph node group. Multivariate analysis showed that the administration of oxaliplatin chemotherapy to the pericolic lymph node group did not lead to a significant difference in the overall survival (p = 0.594). LIMITATIONS: The study was limited by its retrospective design and single institutional data analysis. CONCLUSIONS: This study suggests that the anatomic extent of metastatic lymph nodes could affect patient prognosis, and the effect of oxaliplatin-based adjuvant chemotherapy may not be prominent in stage III colon cancer with isolated pericolic lymph node metastasis.