Cryptosporidium spp.is a parasite more common in immunocompromised individuals and causes a symptomatic enteritis. In this study, we were aimed to investigation of relationship between the process of chemotherapy and incidence of Cryptosporidium spp. in cancer patients. The stool samples were obtainedfrom 57 cancer patientsduring chemotherapy atthe Oncology Center of Cumhuriyet University Hospital and also from 65 healty person as control groups. Personal characteristicsandclinical data of paDCERFVtientswere writtentoa questionnaire such as how long they havereceived chemotherapy. All samples were examined for Cryptosporidium spp. by Direct Fluoresan Antibody (DFA).The Cryptosporidium antigen was determined17.5% by DFA in 57 cancer patients.Also, antigen was determined6.1% by DFA in control group (χ2=3.87 p<0.05). The relationship between the length of the chemotherapy of cancer patients and incidance of Cryptosporidiosis was determined to be statistically significant. Chemotherapy treatment process of individuals who were DFA positive on average 19.4 weeks, while the group of patients who were DFA negative average of 12.7 weeks (p<0,05 Mann-Whitney U=81,0 ).In Conclusion, immun-suppressed individuals against easly transmitted parasites from environment such as Cryptosporidium spp. must be protected. Particularly in patients receiving cancer treatment, if chemotherapy process becomes longer, may increase the risk of cryptosporidiosis
