OBJECTIVES: Anti-cancer chemotherapeutic pharmaceutical agents have some toxic effects to normal cells. Therefore, the main factors to increase therapeutic effects are to destroy cancer cells specifically and appropriate dosage of anti-cancerous agents. Cancer cells are have being studied in many ways by using cell culture technologies in developed countries. We aimed to determine the chemosensitivity of colorectal cancer cases.METHODS: From February 2013 through February 2014, Histoculture drug response assay data were obtained from 6 colorectal cancer surgical specimens held in State Central Hospital. Cultures and culture media were prepared by R. Hoffmans methods. We examined chemosensitivities of the tissue to carboplatin, irinotecan, doxorubicin, 5-fluorouracil and oxalaplatin. Cutoff inhibition rates were determined with each drug for colorectal cancer and were used to calculate predictabilities for chemosensitivity responses.   We also prepared double samples from the culture and made histologic and cytologic analysisRESULTS: The evaluability of the histoculture drug response assay was at 83,3%. Predictability including true-positive and true-negative rates of 83,3% and 100% was observed. CONCLUSIONS: Cancer cells deaths are dependent from dosages of the candidate medications and it shows it is possible to use drug sensitivity methods in oncologic clinical practice.