Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 18 4 2023 11 22 526 534 EN Latif Mohammed Department of Microbiology, College of Medicine, University of Sulaimani, Sulaimani, Iraq Ahmed Amin Department of Biology, College of Science, University of Sulaimani, Sulaimani, Iraq Rezan Mohammed Department of Biology, College of Science, University of Sulaimani, Sulaimani, Iraq Shad Mohammed Department of Biology, College of Science, University of Sulaimani, Sulaimani, Iraq Lava Ahmed Department of Biology, College of Science, University of Sulaimani, Sulaimani, Iraq Vania Ahmed Wise Private Preparatory School for Girls, Sulaimani, Iraq Shaz Majid Ashty Private Elementary School, Sulaimani, Iraq Bryar Mohammed Hiwa Cancer Hospital, Sulaimani, Iraq 2023 04 26 2023 11 22 Introduction: Toxoplasma gondii is an opportunistic protozoan parasite that causes a life-threatening disease – toxoplasmosis – in immunocompromised individuals, including patients with cancer. This prospective cross-sectional study set out to determine the prevalence of toxoplasmosis in patients with cancer compared with that of healthy individuals. Materials & Methods: Anti-T.gondii IgG and IgM antibodies were measured in the blood samples of 113 patients with cancer (80 with solid organ tumours and 33 with haematological malignancies) and 82 healthy controls, using chemiluminescence microparticle immunoassay (CMIA). Results: The prevalence of anti-T.gondii IgG was 39.8% in the patient group and 24.4% in the control group, which amounted to a significant difference (p = 0.024). Only one case of anti-T.gondii IgM positivity was observed in the patient group, and no IgM seropositivity was reported in the control group. Moreover, the seroprevalence of anti-T.gondii IgG was non-significantly higher (p = 0.102) in the patients with haematological malignancies (51.5%) than in those with solid organ tumours (35%). Conclusion: These results demonstrate that the prevalence of T. gondii infection is higher in patients with cancer than in healthy individuals. Therefore, T. gondii screening in patients with cancer is recommended. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/3929 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/3929/1329