Chemoradiotherapy with Concurrent Regional Arterial Chemotherapy for Locally Bulky Unresectable Rectal Cancer: A Case Series

<b><i>Introduction:</i></b> We evaluated the feasibility and efficacy of chemoradiotherapy with concurrent regional arterial chemotherapy (CRT/RAC) for locally bulky unresectable rectal cancer (LBURC). <b><i>Case Presentation:</i></b> We retrospectively reviewed 9 patients with LBURC who received CRT/RAC between January 2012 and December 2018. The regimen consisted of chemoradiotherapy and 3 cycles of regional arterial chemotherapy. Surgery was performed 6 weeks after completion of radiotherapy. The median longest tumor diameter was 10 cm (range 8.2–13.6). Grade 3 toxicity and postoperative complications occurred in 3 and 4 patients, respectively. All patients showed partial response according to the Response Evaluation Criteria in Solid Tumors (RECIST). One patient refused the operation after completion of the scheduled regimen but then had a bowel obstruction and had to undergo urgent surgery. Of the 8 patients who underwent scheduled surgery, all had R0 resection without multivisceral resection; 3 achieved pathological complete response and 5 exhibited good tumor regression. The median follow-up period was 35 months (range 9–63). Recurrences occurred in 3 of 9 patients (pelvic relapses in 2 and lung in 1). <b><i>Conclusion:</i></b> CRT/RAC appeared to be beneficial to LBURC, as it achieves remarkable rates of R0 resection, good tumor regression, and pathologic complete response. These preliminary results have to be confirmed in larger cohorts of patients.