Taichi Yoshida, Koji Fukuda, Daiki Taguchi, Kazuhiro Shimazu, Masahiro Inoue and Hiroyuki Shibata
Introduction: New drugs have improved the outcome of metastatic colorectal cancer treatment. In Japan, more than 10 agents with at least seven different mechanisms such as 5-fluorouracil (5-FU), irinotecan (IRI), oxaliplatin, angiogenesis inhibitors, anti-epidermal growth factor receptor antibodies, regrafenib, and TAS-102, have been approved. With the increase in the number of alternatives, the importance of choosing the agents increases. To suppress the toxicities of agents is also necessary. To increase the quality of life of the patients should be taken into consideration for their longer survival. TAS-102 has proved to be an effective and safe agent for the 3rd or 4th lines of advanced colorectal cancer.
Presentation of case: We report a case of a patient who had suffered severe adverse events from standard firstline chemotherapy with 5-FU derivative and IRI. She did not want to undergo any more intensive chemotherapy. Toxicity and anxiety made her evade the standard combination chemotherapy. For this patient, TAS-102 achieved over 30% tumor shrinkage and more than 1-year progression-free survival with acceptable toxicities.
Conclusion: TAS-102 can result in a better outcome for a responder when given as an earlier line of therapy. In future, predictive biomarkers of TAS-102 should be identified for better use of this agent.