Abstract 761P
Background
Bowen's disease (BD) is defined as an in-situ squamous cell carcinoma (SCC) of the epidermis. It has an incidence of 20-28 cases per 100,000 population per year. The major etiological factors of BD include ultraviolet light exposure, immunosuppression, and Human Papilloma Virus (HPV) infections. The development of melanoma, sarcoma, and non-epithelial skin as second primary malignancies (SPMs) following BD is a very unusual event rarely mentioned in the literature. No Studies discussed the association between Skin SPMs and BD. So, the purpose of this study was to evaluate the risk of all skin SPMs following BD across all age groups.
Methods
The Surveillance Epidemiology and End Result (SEER) database was used to obtain the data of patients diagnosed with BD from 2020 to 2021. We used MP-SIR session with multiple outcome analysis and the event was defined skin melanoma, Kaposi sarcoma and non-epithelial skin neoplasms. Excess absolute risk (EAR) was measured per 10,000. The Standardized Incidence ratio (SIR) was computed as observed/expected (O/E) with a 95% confidence interval (CI).
Results
Out of 1331 patients with BD, 15 patients developed skin SPMs. Kaposi sarcoma SPMs following BD had an O/E of 02.49 (P>0.05, EAR = -0.09) in the 2–11-month interval. Along a decade of follow-up, the O/E was 9.45 (P>0.05, 95%CI: 0.24 - 52.64, EAR = 0.62). There was a decreased risk of melanoma SPMs (P>0.05, 95%CI: 0.00-6.35, EAR = -5.30) in the 2–11 months interval while after 120+ months of follow-up, the O/E was 1.04 (P>0.05, 95%CI: 0.22–3.05, EAR = -0.31). The overall risk of developing additional non-epithelial skin SPMs had an O/E of 3.82 (P>0.05, 95%CI: 0.10-21.27, EAR = -1.54). For middle-aged, the risk of skin excluding basal and squamous SPMs had an O/E of 0.99 (P>0.05, 95%CI: 0.20-2.88, EAR = 0.04) while the elderly had an O/E of 0.36 (P>0.05, 95%CI: 0.04-1.30, EAR = -7.46).
Conclusions
The results of this study show BD had no significant risk to develop Kaposi sarcoma, melanoma and non-epithelial skin SPMs. Thus, decreasing the burden of skin SPMs among the survivors of BD and improving the psychological status. However, we recommend middle-aged and elderly to undergo routine follow up for the suspicious lesions putting into consideration the other risk factors associated with skin SPMs.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.