HPV and oral cancer

Human papillomavirus (HPV) is a group of more than 200 related viruses that are spread through direct contact, including sexual contact. While many of these strains cause no symptoms and clear up on their own, some types can lead to serious health issues, including oral cancer. Oral cancer, a type of head and neck cancer, refers to cancers that affect the mouth, throat, lips, and surrounding areas. While tobacco and alcohol use have long been considered the primary risk factors for oral cancers, HPV, particularly the high-risk strains such as HPV-16, has increasingly been recognized as a major contributor to the development of oral cancers.

The Link Between HPV and Oral Cancer

HPV infections are common, with most sexually active individuals acquiring the virus at some point in their lives. The relationship between HPV and oral cancer has become more apparent in recent decades as the rates of HPV-positive oropharyngeal cancers (cancers that affect the back of the throat, including the base of the tongue and tonsils) have risen significantly, particularly among younger adults who do not have a history of tobacco or heavy alcohol use.

The types of HPV most strongly associated with oral cancers are HPV-16 and HPV-18. These strains are known for their ability to integrate into the host’s DNA, causing mutations that can lead to the uncontrolled cell growth typical of cancer. When HPV infects the cells of the mouth or throat, it can lead to changes in the DNA of those cells, promoting the development of cancer.

HPV-Positive Oral Cancer

Oral cancers caused by HPV tend to occur in the oropharyngeal region, which includes the tonsils, soft palate, and the back of the throat. The typical risk factors for oral cancer, such as smoking and drinking, are not present in HPV-related oral cancers, leading to a distinct set of characteristics for these patients. HPV-positive oral cancers are generally diagnosed in individuals who are younger (under 50) and who may not have the usual lifestyle risk factors associated with oral cancer.

Research has shown that HPV-positive oral cancers may have a better prognosis compared to those caused by tobacco and alcohol use. One reason for this is that HPV-related cancers tend to respond better to treatment, including radiation therapy and chemotherapy. Additionally, people with HPV-positive oral cancers are often diagnosed at an earlier stage when treatment options are more effective.

Risk Factors for HPV-Related Oral Cancer

While HPV infection is the primary cause of HPV-related oral cancer, there are certain risk factors that increase the likelihood of contracting the virus and developing cancer:

1. Oral Sex: HPV is most commonly transmitted through sexual contact, including oral sex. Those who engage in oral sex with multiple partners or who begin sexual activity at an early age are at higher risk for HPV infection and its potential to lead to oral cancer.

2. Immune System Weakness: Individuals with weakened immune systems, such as those living with HIV/AIDS or undergoing immunosuppressive treatments (e.g., organ transplant recipients), are more susceptible to persistent HPV infections, which increases the risk of cancer development.

3. Age: The majority of HPV-related oral cancers are found in individuals between the ages of 40 and 60, with the highest rates observed in people in their 50s and 60s. However, as HPV-related oral cancers are more common in younger people, the demographic of those affected is changing.

4. Smoking and Alcohol Use: While smoking and alcohol use are not the primary causes of HPV-related oral cancer, they can still contribute to the development of cancer in people who have persistent HPV infections. These behaviors can increase the likelihood of an HPV infection leading to cancer.

Prevention of HPV and Oral Cancer

There are several ways to reduce the risk of developing HPV-related oral cancer, though no method is entirely foolproof. The following are some preventative measures:

1. HPV Vaccination: The most effective way to prevent HPV-related cancers is vaccination. The HPV vaccine, which is recommended for both boys and girls between the ages of 11 and 12, helps protect against the high-risk strains of HPV, including HPV-16. Vaccination can significantly reduce the risk of oral, cervical, and other cancers caused by HPV.

2. Safe Sexual Practices: Using barrier methods, such as condoms or dental dams, during oral sex can reduce the risk of HPV transmission. While these methods do not eliminate the risk entirely, they can significantly lower the chances of contracting the virus.

3. Regular Oral Cancer Screenings: Early detection is key when it comes to treating oral cancer. Regular checkups with a dentist or healthcare provider can help identify abnormal growths or lesions in the mouth and throat. If any suspicious areas are detected, a biopsy can be performed to determine if cancer is present.

4. Limit Smoking and Alcohol Consumption: Avoiding or quitting smoking and limiting alcohol consumption can help reduce the risk of developing oral cancer. Smoking and alcohol use are known to increase the chances of HPV infections leading to cancer and can also negatively impact the immune system’s ability to fight the virus.

Symptoms of HPV-Related Oral Cancer

HPV-related oral cancers may not present symptoms in the early stages, which is why they are often diagnosed at a more advanced stage. However, when symptoms do occur, they may include:

• A persistent sore throat or feeling of something being stuck in the throat

• Pain or difficulty swallowing

• Hoarseness or voice changes

• Swollen lymph nodes in the neck

• Unexplained weight loss

• Mouth sores or ulcers that don’t heal

• Bleeding from the mouth or throat

Anyone experiencing these symptoms, especially those with known risk factors for HPV or oral cancer, should seek medical attention promptly.

Treatment for HPV-Related Oral Cancer

Treatment for oral cancer caused by HPV typically involves a combination of surgery, radiation therapy, and chemotherapy. The specific treatment plan depends on the size, location, and stage of the cancer. In general, HPV-positive cancers tend to be more responsive to treatment, and patients may experience a higher survival rate compared to those with HPV-negative cancers. The presence of HPV infection in the cancer cells may also influence the type of treatment that doctors recommend.

• Surgery: If the cancer is localized, surgery may be performed to remove the tumor or affected tissue. In some cases, reconstructive surgery may be necessary to restore function and appearance after the removal of cancerous tissue.

• Radiation Therapy: Radiation therapy is often used to target cancer cells that remain after surgery or to shrink tumors before surgery. It can be used alone or in combination with chemotherapy.

• Chemotherapy: Chemotherapy may be used alongside radiation therapy to treat more advanced cases of oral cancer. It is often given in cycles and may be combined with targeted therapies to improve outcomes.

Conclusion

HPV has become a significant factor in the rise of oral cancers, particularly in the oropharyngeal region. With the understanding that HPV, particularly HPV-16, is a leading cause of these cancers, prevention methods like the HPV vaccine, safe sexual practices, and regular screenings have become essential in reducing the burden of this disease. While HPV-related oral cancers often present a better prognosis than tobacco-related oral cancers, early detection and treatment are crucial for a favorable outcome.