When you first start chemotherapy for colorectal cancer, you'll likely be treated with a combination of drugs. The standard treatment for colorectal cancer is 5-FU, which was the first chemotherapy drug to be proven effective in colorectal cancer and has become the standard treatment option for colorectal cancer, plus oxaliplatin and irinotecan.

However, you have changed drugs as the cancer was not controlled well by the therapy mentioned above, and the medications have been changed to fewer drugs in the new therapy. What could be the reason?

"Because the patient may have become a little weaker during chemotherapy, or the cancer may have progressed from the beginning. In such cases, it is more positive in terms of the patient's quality of life to administer a targeted therapy or a combination of one or two drugs that are effective than to administer a large number of chemotherapy drugs all at once," explained Professor Jeong Hee-cheol of the Department of Oncology at Gangnam Severance Hospital on the YouTube channel with the same name as the hospital.

Colorectal cancer patients often wonder why they can take fewer medicines even though they did not get better with many before. They tend to think they should use stronger medicines if the existing ones don't work, but Professor Jeong says this is not necessarily the case.

"Even if the number of drugs is reduced, the survival period does not decrease that much, so for patients who do not respond well to initial chemotherapy, we have a strategy of administering targeted therapies or chemotherapy drugs that are effective alone or in combination with one or two drugs," Jeong said.