Induction Chemotherapy for Locally Advanced Rectal Cancer: A Potential Role and Room for Improvement

Purpose: Pre-operative long course chemo-radiotherapy (LCRT) facilitates resection of locally advanced rectal cancers (LARC). Distant metastasis is however, the most common pattern of failure. We aimed to study our experience in treating LARC patients and the role of induction chemotherapy. Methods: This was a retrospective study of electronic records of our patients with LARC. Results: Ninety three such patients were treated under our oncology team in the City General Hospital, Stoke-On-Trent, between September 2010 and Sept 2014. The median age was 65 years. Fifty two patients (55.9%) were staged as IIIB (T3-4 N1 M0) and 24 patients (25.6%) were staged as IIIC (T1-4 N2 M0). All patients had preoperative down-staging LCRT. In addition, 6 weeks of flouorpyrimidines based induction chemotherapy was used in 54 patients (58.1%) prior to LCRT. Ninety patients had surgical treatment; 86 patients (95.6%) had negative resection margin (R0) and 4 (4.4%) had residual microscopic tumours (R1). Sixteen patients (17.7%) had pathological complete response (pCR) and 61 (67.8%) pathological partial response (pPR). Down-staging with LCRT was possible in 87% of patients who had initial induction chemotherapy compared to 83.3% of patients who had no induction chemotherapy. Forty three patients (47.8%) had postoperative adjuvant chemotherapy with flouropyrimides based chemotherapy. On follow-up, 8 patients (8.9%) had distant metastases but there were no local recurrences. The median disease free (DFS) and overall survival (OS) probabilities have not been reached over the follow up period. The 3 years DFS and OS probabilities for all patients was 85% and 94% respectively. Conclusion: The current LCRT is highly effective in down-staging LARC. Induction chemotherapy has increased the resectability rate in patients with high risk locally advanced disease (T3 T4) but further progress is need in that area for long term benefits of patients with LARC.