HPV infection is responsible for approximately 5% of the total global cancer cases. Among HPV-related cancers in women, cervical cancers constitute 93% [1].
In 90% of cases, the body controls the infection so those who develop lesions mount an effective cell-mediated immune (CMI) response, and the lesions regress. Failure to develop such a response results in persistent infection and, in the case of the high-risk HPVs, an increased probability of progression to CIN 2+. Regular screenings and HPV vaccinations can significantly reduce the risk of HPV-related cancers.
HPV is known to cause several types of cancer. The following are the most common types of cancer that can be caused by HPV:
Cervical cancer was the fourth leading cause of cancer and cancer deaths in women in 2020, with an estimated 604 000 new cases and over 340 000 deaths (8% of all female cancer deaths). HPV16 and HPV18 together are responsible globally for 71% of cases of cervical cancer. HPV45 accounts for 6%, HPV31 for 4%, HPV33 for 4%, HPV52 for 3% and HPV58 for 2% of cervical cancer cases [2]. Together, these 7 HPV types account for approximately 90% of the squamous-cell carcinomas that are positive for HPV DNA. Most cervical cancer cases in 2020 (88%) occurred in LMICs, where they account for 17% of all cancers in women, compared with only 2% in high-income countries (HICs).
HPV types 16 and 18 are associated with 85% of HPV-related head and neck cancers and 87% of all anal cancers – the second and third most frequent HPV related cancers with, respectively, 52 000 and 29 000 estimated cases in 2018.
A multicenter clinical trial in heterosexual men showed a prevalence of HPV (all types) of 19% at the penis, 13% at the scrotum, 8% at the perineal/perianal region and 21% at any site. A systematic review of genital HPV prevalence in men aged over 18 years concluded that prevalence peaked at slightly older ages than in women and then remained constant or decreased slightly with increasing age.
HPV6, HPV11 and other types can also cause a rare condition (incidence <4 cases per 100 000 persons) known as recurrent respiratory papillomatosis (RRP), in which warts form on the larynx or other parts of the respiratory tract with the risk of airway obstruction [4].
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