FOLFOX and intensified split-course chemoradiation as initial treatment for rectal cancer with synchronous metastases

Abstract

Background: Optimal initial management of rectal carcinoma with synchronous metastases (RCSM) is controversial–both for patients being treated with curative and palliative intent. This study aims to evaluate the use of an upfront treatment strategy combining FOLFOX chemotherapy with split-course pelvic chemoradiation (FOLFOX + CRT) for patients with RCSM. Material and methods: An analysis of all patients who commenced treatment with FOLFOX + CRT at our institutions between January 2009 and June 2014 was performed. The regimen consisted of a total of 12 weeks of treatment with split-course pelvic chemoradiation (50.4Gy with concurrent oxaliplatin and 5-FU) alternating with FOLFOX chemotherapy. Restaging imaging was performed following treatment, with subsequent management as per local standard of care. Results: 78 patients (15 with resectable liver-only metastases) were identified. 77 (99%) completed at least 45Gy of radiation and 87% completed ≥75% of planned dose intensity of both oxaliplatin and 5FU. Two (2.6%) patients died within 30 days of treatment. Rates of radiological complete or partial response for local and metastatic disease were 90% and 66%, respectively. 24% patients had radiological disease progression of metastatic disease. Median overall survival for patients with unresectable metastatic disease at baseline was 23 months (95%CI: 19–28). 12 patients underwent radical surgery to both the rectum and liver and had an estimated 3-year overall survival rate of 62% (95%CI: 37–100). For those patients who did not proceed to rectal surgery, only 7% required palliative re-irradiation or surgery at a later date and all >20months from initial treatment. Conclusions: In patients with unresectable metastatic disease, FOLFOX + CRT provides durable pelvic control for the majority without the need for additional local treatment. For patients with an advanced primary tumor and synchronous resectable liver-only metastases, FOLFOX + CRT can be considered a feasible and tolerable upfront treatment option.