Basal cell carcinoma prevalance in psoriasis patients

Introduction Psoriasis is a chronic inflammatory disease of the skin and joints that affects 3–4% of the population worldwide. It has been suggested that patients with chronic inflammatory diseases such as rheumatoid arthritis, Crohn's disease or psoriasis might be at increased risk of cancer. Due to the exposure to immunosuppressive agents, methotrexate, cyclosporine, and UV therapies, there seems to be increased systemic cancer risk in patients with psoriasis. However, the association between psoriasis and the risk of non-melanoma skin cancer (NMSC) is still controversial. In NMSC types, there are many studies about relationship between squamous cell carcinoma (SCC) with psoriasis, but there are limited studies about basal cell carsinoma (BCC). In this study, it was aimed to evaluate the frequency of BCC in psoriasis patients and to compare it with controls and to examine BCC-related factors. Material and methods The study was carried out with patients who were followed up with a diagnosis of psoriasis between January 1, 2020 and July 1, 2020 to the Dermatology Outpatient Clinic of Bezmialem Vakıf University Medical Faculty Hospital. The study was conducted with 346 psoriasis patients and 306 age and sex matched controls. The pharmacological treatments, demographic and clinical characteristics of the patients,was recorded. Psoriasis severity was evaluated with Psoriasis Area and Severity Index (PASI). BCC diagnosis was made histopathologically in clinically suspected cases. Results The mean age of the patients and controls was 49.9 ± 15.8 vs 49,4 ± 13,4 years, respectively. 53.7% of the patients and 52.2% of controls were female. Demographic characteristics of patients and controls were similar. BCC was observed in 6.6% (n = 23) of the patients and in 2.9% (n = 9) of the control group. The frequency of BCC in psoriasis patients was higher than in controls (p=0,029). The most common BCC type in patients was nodular BCC (39.1%). In psoriasis patients, the mean age of those with BCC was higher (p<0.001), the presence of arthritis (p<0.001) and smoking (p=0.003) were more frequent. Among the psoriasis treatments, the frequency of BCC was higher only in patients with treated PUVA treatment (p<0.001). The number of PUVA sessions was higher in patients with BCC, compared to those without BCC (p=0.010). Conclusion The frequency of BCC increases in psoriasis patients. PUVA therapy may increase the risk of BCC, therefore patients with psoriasis receiving PUVA therapy should be screened for BCC.