Use of octreotide as second-line treatment for concurrent chemoradiation induced diarrhea refractory to loperamide

Abstract

3704 Background: To prospectively evaluate efficacy of octreotide in treatment of chemoradiation induced diarrhea refractory to conventional loperamide treatment. Methods: Our study consists of 38 intractable diarrhea patients resistant to loperamide, out of 56 colon/rectum adenocarcinoma patients (T3–4NXM0) treated at Department of Radiation Oncology, Inonu University, between September 2002 and April 2003. All patients were treated with conventional radiotherapy (50.4 Gy, 1.8 Gy/fraction) with high-energy photons and concurrent 500mg/m2/week i.v. bolus 5FU. Thirty-eight patients had Grade 3 or 4 gastrointestinal toxicity during chemoradiation, according to National Cancer Institute Common Toxicity Criteria (NCI-CTC). Diarrhea failed to improve after 48 hours of p.o. loperamide (4 mg tid) administration on outpatient basis. As 38 patients were assigned to receive octreotide (150 mg tid) subcutaneously for 5 consecutive days, 8 patients who required parenteral support due to severe cramping, incontinence, gross bloody diarrhea were not included in the trial. Complete resolution of diarrhea was considered therapeutic response, whereas partial or no improvement in diarrhea to octreotide application for 5 days was documented as therapeutic failure. Results: Diarrhea, recorded as NCI-CTC Grade 3 & 4, was largely experienced in the first two weekly cycles of 5FU administration concurrent with radiotherapy; 19 (50%) patients in the 1st, 11 (31.6%) in the 2nd, 4 (10.5%) in the 3rd, and 3 (7.9%) in the 4th cycles. Octreotide application resolved diarrhea completely in 33 patients out of 38 cases (86.8%) without any side effects (1st day, 5; 2nd day, 10; 3rd day, 15; 4th day, 2; and 5th day, 1 cases). Five octreotide irresponsive patients (13.2%) discontinued chemoradiation to receive further supportive treatment by parenteral support of fluids and electrolytes with alternative antidiarrheal treatments. Conclusions: Daily subcutaneous octreotide application for five days seems to be an effective, tolerable second-line treatment for concurrent chemoradiation induced diarrhea refractory to loperamide. No significant financial relationships to disclose.