The following is a summary of “Prognostic factors for treatment failure of photodynamic therapy and 5-fluorouracil in Bowen’s disease,” published in the September 2024 issue of Dermatology by Ahmady et al.
Researchers conducted a retrospective study to determine the factors associated with treatment failure after 5-fluorouracil and PDT in Bowen’s disease (BD) and to test the hypothesis that lesion thickness and follicular extension predict treatment outcome.
They derived data from a non-inferiority randomized trial in which 169 patients were treated with 5% 5-fluorouracil cream twice daily for 4 weeks or 2 sessions of MAL-PDT with 1-week intervals. All patients had histologically confirmed BD of 4–40 mm. The initial 3 mm biopsy specimens were re-examined to measure the maximum histological lesion thickness and extension along the hair follicle. Univariate and multivariate logistic regression analyses were used to calculate ORs with 95% CI and P-values to evaluate the association between potential risk factors for treatment failure at one-year follow-up.
The results showed that histological lesion thickness was not significantly associated with treatment failure (OR 0.84, P=0.806), nor was involvement of the hair follicle (OR 1.12, P=0.813). Lesion diameter was the only risk factor significantly associated with a one-year risk of treatment failure (OR=1.08 per mm increase, P=0.021). When using the median value of 10 mm as a cut-off point, the risk of treatment failure was 23.4% for lesions > 10 mm compared to 10.3% for lesions ≤10 mm (OR 2.66, P=0.028).
They concluded that only clinical lesion diameter was identified as a prognostic factor for response to non-invasive therapy in BD.
Source: karger.com/drm/article/doi/10.1159/000541396/913257/Prognostic-factors-for-treatment-failure-of
