Hidradenitis suppurativa and malignancy risk: a systematic review

Background: Researchers are increasingly focused on the long-term health implications of hidradenitis sup purativa (HS), a chronic and inflammatory skin condition. A key area of investigation is whether the persistent inflammation and immune system dysfunction seen in HS could lead to a higher risk of cancer for patients. While this connection is biologically plausible, the actual level of risk and the specific types of malignancies involved are still not fully understood and require further study. Methodology: This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive search of PubMed, Web of Science, and CENTRAL from 2015 onward identified relevant observational studies and qualifying case series that assessed cancer risk in defined HS populations. Data on study characteristics, cancer outcomes, and risk measures were extracted. Methodological quality was assessed using the Newcastle-Ottawa Scale and the Murad et al. tool. Results: Four studies met the inclusion criteria, encompassing over 230,000 participants from Denmark, South Korea, and the United States. The synthesis confirms a significantly elevated risk of squamous cell carcinoma (SCC) arising within chronic HS lesions, a distinct entity marked by anogenital location, aggressive histology, and high mortality. Furthermore, large-scale cohort studies demonstrate increased overall cancer risk in HS patients, with notably elevated risks for Hodgkin lymphoma, non-melanoma skin cancer, and cancers of the oral cavity, digestive system, respiratory tract, and prostate. The evidence does not support a consistent role for HPV in these malignancies. Persistent inflammation, tissue remodeling, and immune dysregulation are proposed as key pathogenic drivers. Conclusion: This review confirms that HS is associated with an increased risk of certain malignancies, underscoring its nature as a systemic inflammatory disease and the need for heightened clinical vigilance, particularly for SCC and lymphoma. Further research is required to clarify underlying mechanisms, refine risk stratification, and guide surveillance strategies.