[Chemotherapy-induced diarrhea]

Chemotherapy-induced diarrhea is a well-documented side effect of many cancer treatments and is associated with increased morbidity and mortality. Chemotherapy-induced diarrhea negatively impacts patient quality of life and treatment outcome by requiring dose limitations or treatment interruption. The chemotherapeutic agent CPT-11 (irinotecan) has shown promising results as a single agent and in combination chemotherapy for the treatment of colorectal and small cell lung cancer. However, delayed onset diarrhea is considered to be its major dose-limiting toxicity. In some cases, it can be life threatening. To prevent CPT-11-induced delayed diarrhea, oral alkalization (OA) and control of defecation (CD) [Int J Cancer 92: 269-275, 2001] were developed based on fundamental studies [Int J Cancer 83: 491-496, 1999; Cancer Res 62: 179-187, 2002]. Oral administration of antibiotics [Cancer Res 56: 3752-3757, 1996; Clin Cancer Res 7: 1136-1141, 2001] or kampo medicine [Jpn J Cancer Res 86: 978-984, 1995; Jpn J Cancer Res 86: 985-989, 1995] to decrease beta-glucuronidase activity derived from bacteria in the large intestine was also reported to be successful in preventing delayed diarrhea. When CPT-11-induced delayed diarrhea occurs, the conventional treatment is loperamide [J Natl Cancer Inst 86: 446-449, 1994], and the early recognition and treatment of diarrhea with this opioid has reduced, although not entirely eliminated, patient morbidity. Other therapies are needed to treat patients with loperamide-refractory CPT-11 induced diarrhea, and the successful use of the somatostatin analogue octreotide has been reported [Support Care Cancer 9: 258-260, 2001; Ann Oncol 12: 227-229, 2001; Proc Am Soc Clin Oncol 21: 387a, 2002].