Oropharyngeal Cancer

Overview

Oropharyngeal cancer is a type of head and neck cancer that arises from the oropharynx, which is part of your throat. The middle section of the throat, including the soft palate, the back third of the tongue, the tonsils, and the side and back walls of the throat, make up the oropharynx. It is distinct from oral cancer, which affects the mouth’s structures (the lips, gums, the front two-thirds of the tongue, and the lining of the cheeks and lips).

Risk factors for oropharyngeal cancer include:

• Human papillomavirus (HPV) infection: Infection with certain strains of HPV, especially HPV-16, is by far the leading cause of cancer of the oropharynx. HPV-related oropharyngeal cancers tend to occur in younger individuals and have a better prognosis compared to tobacco-related cancers. Early data suggest that HPV vaccines could help prevent oropharyngeal cancer.
• Number of sexual partners: A higher number of sexual partners could be a risk factor, as number of oral sexual partners has been linked to higher risk of HPV infection and oropharyngeal cancers.
• Tobacco use: The most significant risk factor includes smoking cigarettes, cigars, or pipes, and using smokeless tobacco (chewing tobacco).
• Alcohol consumption: Heavy use of alcohol can increase the risk, and concurrent use of alcohol and tobacco magnifies this risk.

Oropharyngeal cancer symptoms may include a sore throat, swallowing difficulty, a lump in your neck, weight loss, pain or ringing in your ears, or changes in your voice.

Diagnosis is generally made through physical examination, imaging studies (like CT or MRI), and biopsy of the suspicious area. Treatment depends on the stage and location of the tumor. It can include surgery, immune therapy, radiation therapy, targeted therapy, chemotherapy, or a combination thereof. The prognosis and treatment approach can also vary based on whether the cancer is HPV-related or not.

Anatomy of the Throat

The throat is a tube wrapped in muscle that starts behind your nose and mouth and extends down the neck to the larynx (or voice box). You use it to bring air into your lungs and food into your stomach.

It includes the orpharynx:

• The back of your nose and mouth
• Soft part of the palate/roof of your mouth
• Tonsils
• The back third of the tongue

And also:

• Epiglottis (the flap that prevents solids and liquids from entering your windpipe)
• Voice box (larynx)
• Windpipe (trachea)
• Esophagus

Symptoms of oropharyngeal cancer include:

• A persistent sore throat that doesn’t go away for several weeks
• Difficulty swallowing (dysphagia) or feeling like you have something stuck in your throat
• A lump in the back of your mouth, throat, or neck
• Unexplained weight loss
• Pain or ringing in your ears
• Changes in your voice
• Persistent cough
• Coughing or spitting up blood
• Unexplained mouth pain or an ulcer that doesn’t heal
• Swelling or white or red patches
• Difficulty moving the jaw or tongue
• Numbness or weakness in certain areas of the throat or tongue
• Persistent bad breath
• Swollen lymph nodes in the neck
• Breathing difficulties

Many of these symptoms are caused by conditions other than cancer, such as infections, benign tumors, or other health problems. However, if you or a loved one experiences any of these symptoms, especially if they persist for weeks, it’s crucial to see a healthcare professional for evaluation. Early diagnosis and rapid treatment can improve your prognosis.

Diagnosis

Your doctor will use a combination of medical history evaluation, physical examination, and various diagnostic tests and procedures to determine if you have oropharyngeal cancer. Diagnosing oropharyngeal cancer typically involves:

1. Medical History and Physical Examination: Your doctor or healthcare provider will conduct a thorough medical history and physical examination. They will ask about your symptoms, risk factors (such as tobacco use, alcohol use, HPV infection, and family history), and any relevant medical conditions.
2. Clinical Evaluation: During the physical examination, the healthcare provider will examine your throat, mouth, and neck for any signs of abnormalities, including lumps, masses, or enlarged lymph nodes.
3. Biopsy: A definitive diagnosis of oropharyngeal cancer requires a tissue sample (biopsy) from the affected area. This can be done in several ways:
   • Fine needle aspiration (FNA): A small sample of tissue or fluid is drawn from a suspicious lump or lymph node using a thin needle.
   • Incisional biopsy: A portion of the abnormal tissue is removed for examination.
   • Excisional biopsy: In some cases, the entire tumor or suspicious area may be removed for examination.
4. Imaging Studies: To determine where the cancer is located, imaging tests (CT, MRI, X-rays) may be ordered.
5. Endoscopy: In some cases, an endoscope (a thin, flexible camera) may be used to examine the throat, larynx, and esophagus. This procedure is called a laryngoscopy or pharyngoscopy, and may be done during your initial office visit if oropharyngeal cancer is suspected.
6. HPV Testing: If your healthcare provider suspects that the oropharyngeal cancer may be HPV-related, a specific test may be performed to detect the presence of HPV in the tumor tissue.
7. Blood Test: HPV related cancers can also often be detected by certain blood tests. 

Once the diagnosis is confirmed, additional tests and evaluations will determine the cancer stage, which helps guide treatment decisions. Staging involves assessing the size and spread of the tumor and whether it has invaded nearby tissues or distant parts of your body.

After a definitive diagnosis and staging, a multidisciplinary team of healthcare professionals, including head and neck cancer surgeons, medical oncologists, radiation oncologists, and others, will develop a treatment plan tailored to the specific characteristics of the cancer and your overall health. Treatment options for oropharyngeal cancer may include surgery, radiation therapy, chemotherapy, immunotherapy, or a combination of these approaches.

Transoral robotic surgery (TORS) and transoral laser microsurgery (TLM) are minimally invasive surgical techniques that use either a robot or a microscope and a laser to remove tumors from the throat through the mouth.

Your head and neck cancer surgeon may remove the lymph nodes in your neck if there is concern that the cancer has spread to them.

Following the removal of larger tumors, free flap microvascular reconstructive surgery may be needed to help restore the structure and function of affected areas.

Radiation Therapy

Radiation therapy uses X-rays, gamma rays, electrons, or protons to bombard cancer cells while attempting to spare healthy tissue nearby. The high energy of these particles makes them lethal to tissue in high doses, so they are directed and concentrated so that only the tumor receives enough radiation to cause damage.

External beam radiation therapy is the most common form of radiation therapy for oropharyngeal cancers.

Chemotherapy

Chemotherapy uses medicines to kill cancer cells or prevent them from growing and dividing. It can be used before surgery to shrink tumors, postoperatively to kill remaining cancer cells, or in combination with radiation therapy.

Immunotherapy

Immunotherapy helps your body’s immune system recognize and attack cancer cells. Some immunotherapy drugs have shown promise in treating head and neck cancers.

Rehabilitation

Due to the location of oropharyngeal cancer, treatments can affect your ability to speak, swallow, and breathe. Rehabilitation may involve speech and swallowing therapy, dietary counseling, and other supportive care measures.

Regular follow-up care after treatment is essential to monitor for recurrence, manage any long-term side effects, and ensure your overall well-being. Your team of specialists will encourage you to discuss the potential benefits and risks of each treatment and help you make informed decisions.

Targeted Therapy

Targeted therapy describes therapeutics that target specific cancer cell proteins or processes without affecting normal cells. Targeted therapies are rarely used for oropharyngeal cancer, with the exception of extremely rare salivary gland cancers of the oropharynx.