Anatomic Subtype Differences in Extramammary Paget Disease: A Meta-Analysis.

Importance: Extramammary Paget disease (EMPD) is a rare, highly recurrent cutaneous malignant neoplasm of unclear origin. EMPD arises most commonly on the vulvar and penoscrotal skin. It is not presently known how anatomic subtype of EMPD affects disease presentation and management.

Objective: To compare demographic and tumor characteristics and treatment approaches for different EMPD subtypes. Recommendations for diagnosis and treatment are presented.

Data Sources: MEDLINE, Embase, Web of Science Core Collection, and Cochrane Reviews CENTRAL from December 1, 1990, to October 24, 2022.

Study Selection: Articles were excluded if they were not in English, reported fewer than 3 patients, did not specify information by anatomic subtype, or contained no case-level data. Metastatic cases on presentation were also excluded.

Data Extraction And Synthesis: Abstracts of 1295 eligible articles were independently reviewed by 5 coauthors, and 135 articles retained. Reporting was in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. The analysis was cunducted in August 2019 and updated in November 2022.

Findings: Most vulvar EMPD cases were asymptomatic, and diagnosis was relatively delayed (mean, 25.1 months). Although most vulvar EMPD cases were intraepidermal (1247/1773 [70.3%]), radical surgeries were still performed in almost one-third of cases. Despite this aggressive surgical approach, 481 of 1423 (34%) recurred, commonly confined to the skin and mucosa (177/198 [89.4%]). By contrast, 152 of 1101 penoscrotal EMPD cases (14%) recurred, but more than one-third of these recurrences were regional or associated with distant metastases (54 of 152 [35.5%]). Perianal EMPD cases recurred in one-third of cases (74/218 [33.9%]), with one-third of these recurrences being regional or associated with distant metastasis (20 of 74 [27.0%]). Perianal EMPD also had the highest rate of invasive disease (50% of cases).

Conclusions And Relevance: The diagnosis and treatment of EMPD should differ based on anatomic subtypes. Considerations for updated practice may include less morbid treatments for vulvar EMPD, which is primarily epidermal, and close surveillance for local recurrence in vulvar EMPD and metastatic recurrence in perianal EMPD. Recurrences in penoscrotal subtype were less common, and selective surveillance in this subtype may be considered. Limitations of this study include the lack of replication cohorts and the exclusion of studies that did not stratify outcomes by anatomic subtype.