HPV associated HNSCC
HPV infection is a known risk factor for a subset of head and neck
squamous cell carcinomas (HNSCC). HNSCC refers to cancers that arise in
the squamous cells lining the mucosal surfaces of the head and neck
region, including the oral cavity, oropharynx, larynx, and
hypopharynx.93-103 HPV-associated HNSCC primarily
involves the oropharynx, which includes the tonsils, base of the tongue,
and the soft palate. The most prevalent HPV types associated with HNSCC
are HPV16 and, to a lesser extent, HPV18. These high-risk HPV types are
known to have oncogenic potential and can contribute to the development
of cancer.100-103 The incidence of HPV-related HNSCC
has been increasing over the past few decades, particularly in younger
individuals and those without traditional risk factors such as tobacco
and alcohol use. It is estimated that approximately 70-80% of
oropharyngeal cancers are associated with HPV
infection.100-104
HPV-associated HNSCC is primarily linked to sexual transmission,
particularly through oral-genital contact. It has been suggested that
performing oral sex on an HPV-infected individual may increase the risk
of acquiring HPV infection in the oral cavity and subsequently
developing HPV-related HNSCC.93-103
The oncogenic potential of HPV in HNSCC is mainly attributed to the
expression of the viral oncoproteins E6 and E7. These oncoproteins
interfere with cellular regulatory mechanisms, promoting uncontrolled
cell growth, inhibiting cell cycle control, and evading immune
responses. The disruption of tumor suppressor proteins, such as p53 and
pRb, by HPV oncoproteins contributes to the malignant transformation of
cells.102-104
HPV-related HNSCC often presents with distinct clinical and pathological
characteristics compared to non-HPV-related HNSCC. Patients with
HPV-associated tumors tend to be younger, have a better response to
treatment, and have a more favorable prognosis compared to those with
non-HPV-related HNSCC.100-103
HPV status in HNSCC is typically determined by detecting HPV DNA or by
assessing the expression of specific viral proteins, such as p16. The
presence of HPV in the tumor is associated with improved overall
survival and disease-free survival rates in patients with HNSCC,
particularly in oropharyngeal cancers. HPV status is considered an
important prognostic factor and may influence treatment
decisions.100,103
The treatment of HPV-related HNSCC follows similar principles as
non-HPV-related HNSCC. Treatment options may include surgery, radiation
therapy, chemotherapy, or a combination of these modalities, depending
on the stage and extent of the disease. HPV-positive tumors may have a
better response to treatment and may require less aggressive therapy
compared to HPV-negative tumors.100,103,105