Skip to main content

Advertisement

Log in

Preferential activation of capecitabine in tumor following oral administration to colorectal cancer patients

  • ORIGINAL ARTICLE
  • Published:
Cancer Chemotherapy and Pharmacology Aims and scope Submit manuscript

Abstract

Purpose: Capecitabine (Xeloda) is a novel fluoropyrimidine carbamate rationally designed to generate 5-fluorouracil (5-FU) preferentially in tumors. The purpose of this study was to demonstrate the preferential activation of capecitabine, after oral administration, in tumor in colorectal cancer patients, by the comparison of 5-FU concentrations in tumor tissues, healthy tissues and plasma. Methods: Nineteen patients requiring surgical resection of primary tumor and/or liver metastases received 1,255 mg/m2 of capecitabine twice daily p.o. for 5–7 days prior to surgery. On the day of surgery, samples of tumor tissue, adjacent healthy tissue and blood samples were collected simultaneously from each patient, 2 to 12 h after the last dose of capecitabine had been administered. Concentrations of 5-FU in various tissues and plasma were determined by HPLC. The activities of the enzymes (CD, TP and DPD) involved in the formation and catabolism of 5-FU were measured in tissue homogenates, by catabolic assays. Results: The ratio of 5-FU concentrations in tumor to adjacent healthy tissue (T/H) was used as the primary marker for the preferential activation of capecitabine in tumor. In primary colorectal tumors, the concentration of 5-FU was on average 3.2 times higher than in adjacent healthy tissue (P=0.002). The mean liver metastasis/healthy tissue 5-FU concentration ratio was 1.4 (P=0.49, not statistically different). The mean tissue/plasma 5-FU concentration ratios exceeded 20 for colorectal tumor and ranged from 8 to 10 for other tissues. Conclusions: The results demonstrated the preferential activation of capecitabine to 5-FU in colorectal tumor, after oral administration to patients. This is explained to a great extent by the activity of TP in colorectal tumor tissue, (the enzyme responsible for the conversion of 5′-DFUR to 5-FU), which is approximately four times that in adjacent healthy tissue. In the liver, TP activity is approximately equal in metastatic and healthy tissue, which explains the lack of preferential activation of capecitabine in these tissues.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Author information

Authors and Affiliations

Authors

Additional information

Received: 4 June 1999 / Accepted: 28 October 1999

Rights and permissions

Reprints and permissions

About this article

Cite this article

Schüller, J., Cassidy, J., Dumont, E. et al. Preferential activation of capecitabine in tumor following oral administration to colorectal cancer patients. Cancer Chemother Pharmacol 45, 291–297 (2000). https://doi.org/10.1007/s002800050043

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1007/s002800050043

Navigation