The prognostic significance of HPV, p16, and p53 protein expression in vaginal cancer: A systematic review

Introduction Human papillomavirus (HPV), p16, and p53 have been investigated as prognostic markers in various HPV-related cancers. Within the field of vaginal cancer, however, the evidence remains sparse. In this systematic review, we have compiled the presently published studies on the prognostic significance of HPV and immunohistochemical expression of p16 and p53 among women with vaginal cancer. Material and methods We conducted a systematic search of PubMed, Embase, and Cochrane Library to identify relevant studies published until April 2021. We included studies reporting survival after histologically verified vaginal cancers tested for HPV, p16, and/or p53. Survival outcomes included overall survival, disease-free survival, disease-specific survival, and progression-free survival. Results We included a total of 12 studies. The vast majority of vaginal cancer cases included in each study were squamous cell carcinomas (84%-100%). Seven studies reported survival after vaginal cancer according to HPV status, and the majority of these studies found a tendency towards improved survival for women with HPV-positive vaginal cancer. Three out of four studies reporting survival according to p16 status found an improved survival among women with p16-positive vaginal cancer. For p53, only one of six studies reported an association between p53 expression and survival. Conclusions This systematic review suggests that women with HPV- and p16-positive vaginal cancer have an improved prognosis compared with those with HPV- or p16-negative vaginal cancer. Results for p53 were varied, and no conclusion could be reached. Only 12 studies could be included in the review, of which most were based on small populations. Hence, further and larger studies on the prognostic impact of HPV, p16, and p53 in vaginal cancer are warranted.

Automated summary

This systematic review suggests that women with HPV- and p16-positive vaginal cancer have a better prognosis compared to those with HPV- or p16-negative vaginal cancer. Results for p53 were varied, and no definitive conclusion could be drawn. Further larger studies are needed to determine the prognostic impact of HPV, p16, and p53 in vaginal cancer.