Psoriasis May Be a Protective Factor for Certain Forms of Cancer, Research Suggests

A recent Mendelian randomization (MR) study indicates psoriasis may be inversely associated with uterine corpus cancer in women and prostate cancer in men, which suggests that it may be a protective factor for both diseases.1

Prior studies have indicated a correlation between psoriasis and an increased risk of various forms of cancer, exhibiting an overall prevalence of 4.78% and an incidence of roughly 11.75 per 1000 people annually among patients with psoriasis. A meta-analysis from 2020 indicated additional associations between psoriasis and lung cancer, bladder cancer, keratinocyte cancer, and lymphomas.2

Although MR studies have explored the causal relationship between psoriasis and lung cancer, investigators have noted the results were inconsistent.1

“To obtain a more comprehensive perspective, we used Mendelian randomization analysis to systematically assess the association of psoriasis with the risk of 33 common cancers and synthesized the results by meta-analysis,” wrote Mengsi Liu, Guangdong Cardiovascular Institute and Guangdong Provincial People’s Hospital, Southern Medical University, and colleagues. “The results of this study could provide a valuable reference for cancer screening and surveillance of patients with psoriasis.”1

Investigators collected data from multiple independent databases, UK Biobank, FinnGen Consortium, and other cancer databases. Results were combined using meta-analysis. The trial followed a 2-sample MR approach to find associations between psoriasis and risk of 33 cancers.1

A total of 13,229 patients with psoriasis and 21,543 control cases were utilized to identify psoriasis susceptibility loci, of which 63 were found. Investigators selected instrumental variables by extracting single-nucleotide polymorphisms (SNPs) that were significantly associated with exposure at the genome-wide level (P < 5e-8). SNPs that were associated with cancer, smoking, alcohol consumption, or obesity in previous studies were excluded; only 1 was excluded, as it was found to be directly associated with lung cancer.1

The FinnGen database provided medical and biological data from 500,348 individuals, which included 2502 available disease endpoints. The UK Biobank sample consisted of 420,531 patients between the ages of 40 and 69, including large-scale gene-wide association data for several cancer categories.1

Investigators found a suggestive association between predicted psoriasis and high-risk colon cancer (odds ratio [OR], 1.055; 95% CI, 1.001-1.113; P = .046) and low-risk uterine corpus cancer (OR, .922; 95% CI, .852-.997; P = .042) in the UK Biobank data. The FinnGen consortium saw psoriasis exhibit a suggestive association with vulvar cancer (OR, 1.182; 95% CI, 1.023-1.366; P = .024), uterine corpus cancer (OR, .937; 95% CI, .883-.993; P = .028), and prostate cancer (OR, .973; 95% CI, .948-.999; P = .045). An additional large-scale cancer dataset exhibited a suggestive association between psoriasis and prostate cancer (OR, .968; 95% CI, .942-.995; P = .02).1

Meta-analysis confirmed the association between psoriasis and uterine corpus (OR, .931; 95% CI, .889-.976; P = .003) and prostate cancer (OR, .976; 95% CI, .955-.997; P = .023), while the effect of psoriasis on colon and vulvar cancer was not in the same direction across different populations. No associations with other cancers were observed.1

Ultimately, the team noted that these data exhibit some discrepancies with existing observational cohort studies. This was explained as the MR approach circumventing the influence of environmental confounders, as patients with psoriasis often receive immunomodulatory therapies that may influence cancer risk.1

“This comprehensive MR study based on multiple large-scale data sources suggests that psoriasis may be a potential protective factor for uterine corpus cancer in women and prostate cancer in men,” Liu and colleagues wrote. “Further validation by prospective studies and mechanistic investigations is warranted.”1

References

1. Liu M, Sun Z, Tan P, et al. Associations between psoriasis and risk of 33 cancers: a Mendelian randomization study. BMC Cancer. 2025;25(1):837. Published 2025 May 7. doi:10.1186/s12885-025-14243-4

2. Vaengebjerg S, Skov L, Egeberg A, Loft ND. Prevalence, Incidence, and Risk of Cancer in Patients With Psoriasis and Psoriatic Arthritis: A Systematic Review and Meta-analysis. JAMA Dermatol. 2020;156(4):421-429. doi:10.1001/jamadermatol.2020.0024