PD-L1-Expression in primary and recurrent vulvar squamous cell cancer

Squamous cell vulvar carcinoma is a rare malignant disease of women. In higher tumor stages survival rates are poor. Therapy options are limited. Immunoncology plays an increasing role in the treatment of gynecology cancers. Data on the expression of PD-L1 in vulvar cancer are rare and contradictory. We sought to describe the expression of PD-L1 in VSCC in respect to the clinicopathologic characteristics of the tumor.

We conducted a retrospective analysis including women with primary and recurrent vulvar cancer between 2000 and 2021. A next generation tissue micro array (ngTMA) was constructed for the analysis of PD-L1 expression.

In total 238 women with primary VSCC and 66 cases of local or distant recurrent vulvar cancer were included. 80 women with primary VSCC (33.6 %) had tumors with common positive score (CPS) <1 and 63 women (26.5 %) had tumors with CPS 1- < 10 and 95 women with CPS ≥10 (39.9 %). In the PD-L1 positive group the rates of p53+, groin metastasis, lymphatic invasion and tumor infiltration lymphocytes were higher as compared to PD-L1 negative (CPS <1). There was no significant influence of CPS in overall survival in addition to other prognostic factors (P = 0.13, likelihood ratio test).

PD-L1 expression in primary vulvar cancer is associated with poorer prognosis. Hence, PD-L1 is a possible target for immune checkpoint inhibitors and women might benefit from special treatment options.