Induction chemotherapy with capecitabine and oxaliplatin followed by chemoradiotherapy before surgery in patients with locally advanced rectal cancer

Abstract

Background: Locally advanced rectal cancer (LARC) has a high incidence of local and distant relapse even after adequate treatment. The emerging role of neoadjuvant induction chemotherapy may allow initial down staging of the primary tumor, less toxicity and early treatment of micrometastatic disease followed by chemoradiation with the hope of increased complete response rates before surgery OBJECTIVES: To identify the effect of induction chemotherapy before concurrent chemoradiation (CCRTH) in locally advanced rectal cancer in terms of response and toxicity. Primary end point is assessment of pathological complete response rate after surgery. Secondary end points are disease free survival (DFS) and overall survival (OS) after 3 years follow up.

Patients and methods: Patients with MRI based criteria for staging high-risk LARC (T4 tumors, tumors within 2 mm of mesorectal fascia, T3 tumors at or below levators and T2-4 with LN +ve tumors) were included. Thirty-five patients were recruited. Patients received 12 weeks of induction capecitabine/oxaliplatin followed by concomitant capecitabine and conventional 3D-conformal radiotherapy. Surgery was done at least 6 weeks later .

Results: Five patients (20.8%) had a pathological complete response (TRG 0) (ypT0N0). Another three patients (12.5%) had near complete pathological response (TRG 1). Regarding OS and pathological complete response corrlelation, it was statistically not significant in relation to patients with incomplete pathological response (p = 1).

Conclusion: Induction chemotherapy could be a promising option for better response rates either clinical or pathological for high risk LARC patients with acceptable toxicity.

Keywords: Induction chemotherapy; Locally advanced rectal cancer; Overall survival; Pathological complete response.