From the Guidelines
Human papillomavirus (HPV) type 16 is most likely to cause Squamous cell carcinoma of the anus (SCCA), as it is strongly associated with this type of cancer, representing the causative agent in 80%–85% of patients, usually from HPV16 or HPV18 subtypes, as stated in the study by 1. The association between HPV type 16 and SCCA is well-established, with factors such as anal intercourse, a high lifetime number of sexual partners, and immune suppression increasing the risk of persistent HPV infection and eventually leading to malignancy, as noted in the study by 1. Some key points to consider include:
- HPV type 16 is a high-risk oncogenic strain that can integrate its DNA into the host cell genome, leading to the expression of viral oncoproteins E6 and E7, which interfere with tumor suppressor genes p53 and pRb, disrupting normal cell cycle regulation and promoting cellular transformation.
- The incidence of anal cancer is higher among men who have sex with men (MSM), particularly those who are HIV seropositive, with an incidence of 75–135 per 100 000, as reported in the study by 1.
- Regular screening and HPV vaccination are essential for early detection and prevention of HPV-related cancers, including SCCA. Other options, such as Tubular adenoma of the colon, Condylomata, and Low-grade squamous intraepithelial lesion (LSIL) of the anal canal, are not as strongly associated with HPV type 16 as SCCA, and are therefore less likely to be the correct answer, based on the evidence provided by 1.
From the Research
Lesions Associated with Human Papillomavirus (HPV) Type 16
The following lesions are associated with HPV type 16:
- Squamous cell carcinoma of the anus
- Squamous cell carcinoma in hidradenitis suppurativa 2
- Oropharyngeal squamous cell carcinoma (OPSCC) 3, 4, 5
- Cervical cancer 6
- Low-grade squamous intraepithelial lesion (LSIL) of the anal canal
Specific Lesions and Their Association with HPV Type 16
- Squamous cell carcinoma of the anus: This type of cancer is associated with HPV type 16, among other types 2.
- Tubular adenoma of the colon: There is no direct evidence linking this lesion to HPV type 16.
- Condylomata: These are associated with low-risk HPV types, such as HPV 6 and 11, rather than HPV type 16.
- Low-grade squamous intraepithelial lesion (LSIL) of the anal canal: LSIL can be associated with high-risk HPV types, including HPV 16, but the provided evidence does not specifically link LSIL of the anal canal to HPV type 16.
HPV Type 16 and Its Implications
HPV type 16 is a high-risk strain of the virus that can lead to various cancers, including oropharyngeal squamous cell carcinoma and cervical cancer 3, 6, 4, 5. The association between HPV type 16 and specific lesions can inform diagnosis, treatment, and prevention strategies. Vaccination against HPV, including type 16, is a crucial preventive measure for reducing the risk of associated cancers 6, 2.