Reviewing vulvar Paget's disease molecular bases. Looking forward to personalized target therapies: a matter of CHANGE

OBJECTIVES: To review the published literature on vulvar Paget's disease (VPD) molecular bases, aiming to support the need for tailored treatment in women affected by this 'orphan' tumor. METHODS: MEDLINE-PubMed and Scopus were interrogated using the following algorithm: (extramammary OR extra mammary OR vulvar) AND (paget OR pagets OR paget's) AND (molecular OR biological OR marker OR protein OR target OR expression). The inclusion criteria for papers were: peer-reviewed English-language journals, articles published in the last 30 years, studies focused on fixed research questions, quality assessment on the basis of the relevance and contribution to the selected topics. RESULTS: A total of 42 studies were selected, providing the following results. Molecular markers implicated in cell cycle transitions seem to be related to prognosis and could help to tailor conventional treatments. Fragmented but consistent preliminary data exist on hormonal receptor expression, ERBB2 amplification/overexpression and abnormal vascular proliferation, offering a concrete possibility for target therapy trials. Conversely, other fields linked to the possible use of immunotherapy are currently relatively unexplored, such as the tumor 'immune contexture', programmed death ligand-1 (PD-L1) expression and defects in the mismatch repair system, which is involved in genomic instability and potentially promotes a consistent response to treatment. CONCLUSIONS: Additional effort is needed to further characterize these aspects. Centralization of patients in dedicated units would be beneficial for concentrating patient numbers, collecting valuable clinical data and conducting clinical trials. Interdisciplinary study platforms should be developed and integrated into wider multicentric networks.