INTRODUCTION

Invasive adenocarcinoma (IAC) accounts for about 25% of invasive cervical carcinomas (ICC), a significant proportion of IAC are Human papillomavirus (HPV) independent. Thus, HPV vaccination and screening will not prevent nor detect some IAC.

We aimed to investigate p16, a surrogate marker for hrHPV, in a series of IAC from Mozambique, a country where ICC is the most frequent cancer in women and with a high prevalence of HIV, in order to evaluate if the proportion of HPV associated and independent IAC may differ from a non-endemic HIV milieu.

METHODS

Tissue micro arrays with material from 41 IAC diagnosed at Maputo Central Hospital (MCH) were stained for p16 by immunohistochemistry and classified in a four-grade scale as: strong diffuse (3+), strong focal/moderate intensity (2+), weak sporadic (1+) or no visible staining (0). Histopathological classification was done according to WHO 2020 into HPV-associated and HPV independent types. Ethical approval was received from relevant Mozambican authorities.

RESULTS

38/41 cases had HPV-associated morphology (usual type n=30, mucinous; NOS n=1, intestinal type n=5, signet ring cell type n=1 and villoglandular n=1). 3/41 presented with HPV independent morphology (serous n=2, mesonephric n=1).

p16 was positive in all cases except in one (97.3%). Positivity was strong diffuse in 86%, strong focal or moderate in 11% and sporadic weak in 3% of the cases. The negative case was a serous carcinoma.

CONCLUSION

These data support the relevance of the present morphological classification system in a HIV endemic milieu. However, 2/3 cases with HPV independent morphology tested p16 positive, which needs to be further assessed by hrHPV analyses.

Thus, since 97% of the IAC cases where p16 positive, our data supports the value of hrHPV based screening and HPV vaccination in Mozambican women with potentially an even higher potential to prevent IAC than in an HIV non-endemic setting.