Periocular basal cell carcinoma worldwide distribution - a systematic review

A systematic literature review was performed across seven databases to identify studies reporting the prevalence of PM tumors. Using the Rayyan app, two independent reviewers screened articles published up to 2024, extracting reference center, study period, geographic location, climate, tumor type, prevalence, and case numbers. Statistical analysis was conducted with R software using the "META" package. A random-effects meta-analysis estimated the pooled prevalence of BCC.

Seventy-two studies were included, encompassing 148,497 PM tumors. BCC demonstrated a mean prevalence of 54.53 ± 28.39%, with a pooled prevalence of 61.11% (95% CI: 53.48-68.49). Heterogeneity was high (I² = 99.82%; p < 0.0001). Prevalence was ≤50% in 33 studies, 50-80% in 20, and ≥80% in 19. Of the studies reporting <50% prevalence, 81.8% originated from Asia; among those with ≥80%, 68.4% were from Europe.

BCC accounts for more than half of PM lesions worldwide. It is most prevalent in Western regions, whereas sebaceous gland carcinoma predominates in Eastern countries. Geographic and environmental factors likely shape these differences, warranting further investigation to enhance global understanding.