Treatment combinations with immunotherapy tend to provide better responses in patients with undifferentiated penile intra-epithelial neoplasia (PeIN), despite p16 status.
PeIN is a known precursor for penile cancer; it is related to high-risk human papilloma virus (HPV) and is associated with p16 over-expression.
A new study, led by the Departments of Urology at the Christie NHS Foundation Trust in Manchester, assessed associations between p16 status, patient parameters, treatment choice and outcomes. Data were collected on patients diagnosed with PeIN, who were referred to a single European Network, between 2008 and 2018.
Patient records were used to collect data on demographics, smoking status, performance status, co-morbidities, HPV/p16 status, lichen sclerosus (LS) status, treatment and clinical response.
A total of 137 patients were identified with PeIN and no invasive cancer. Staining for p16 was available in 91 patients, and 74 patients were p16+.
There were no significant differences in disease-free survival (DFS) for smoking status, performance status, co-morbidities and LS, although patients with LS tended to recur sooner.
Overall, p16+ patients showed significantly better DFS over p16− patients (n=67; 10.4 vs 7.4 months; P=.023).
In p16+ patients receiving treatment with imiquimod alone or with surgery, response rates were 100 per cent versus 54 per cent without imiquimod (n=56; P=.017).
In p16− patients receiving treatment with imiquimod alone or with surgery, response rates were 100 per cent versus 56 per cent without imiquimod (n=17; P=.99). Overall, 13.6 per cent of patients progressed to cancer.
The authors say that the results indicate treatment combinations with immunotherapy tend to provide better responses despite p16 status. However, given the limitations in this study, further research is required to confirm the findings.
