Prevalence and Associated Risk Factors of Helminthic Parasites among the Patients with Colorectal Cancer in Western Iran; A Case-Control Study
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Alireza Moayyedkazemi
,
Amal Khudair Khalaf
,
Abdolreza Mirjani
,
Maryam Sepahvand
,
Parastoo Baharvand
,
Hossein Mahmoudvand
Abstract
Background: Helminths modulate host immune responses through immunoregulatory mechanisms that may influence carcinogenesis. We investigated the prevalence and risk factors of helminthic infections among colorectal cancer (CRC) patients in Lorestan Province, western Iran.
Methods: This case-control study enrolled 87 CRC patients and 87 healthy controls from general hospitals between October 2022 and August 2024. Stool samples were examined via direct wet mount and formol-ether concentration, with agar plate culture used to detect Strongyloides stercoralis.
Results: Helminthic infections were found in 15 of 87 CRC patients (17.2%) versus 6 of 87 controls (6.9%). Trichostrongylus spp. was most common (52.4%), followed by Enterobius vermicularis (19%) and S. stercoralis (14.3%). Among CRC patients, age under 40 years was associated with higher infection odds versus those ≥60 years (OR=12.33, 95% CI: 1.38–110.2, P=0.025), while animal contact was protective (OR=0.06, 95% CI: 0.01–0.30, P=0.008). Among controls, rural residence (OR=15.25, 95% CI: 1.70–136.5, P=0.015) and animal husbandry (OR=12.61, 95% CI: 1.32–120.5, P=0.024) increased odds, while frequent fast-food consumption was protective (OR=0.16, 95% CI: 0.03–0.94, P=0.045).
Conclusion: Intestinal helminthic infections were significantly more prevalent among CRC patients than healthy controls, indicating potential clinical relevance in this population. Detection of S. stercoralis in CRC patients, along with links to environmental exposure factors, supports systematic parasitological screening in endemic regions, particularly before immunosuppressive treatment. Larger multicenter studies with molecular diagnostics are needed to clarify the association between helminthic infection and CRC.
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| Files | ||
| Issue | Vol 21 No 3 (2026) | |
| Section | Original Article(s) | |
| Keywords | ||
| Colorectal cancer Infection Malignancy Parasites Iran | ||
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