Head & Neck Oncology
Malignant tumors frequently develop in the head and neck region. Among all the malignancies being formed in the head and neck area, the most common is squamous cell carcinoma. This tumor arises from cells covering the throat, as well as oral and nasal cavities. Other frequently encountered head and neck cancers diseases are tumors of the salivary glands, sarcomas, lymphomas.
Cancer spreads in three different ways:
- Metastasis of cancer cells from the original foci to nearby tissues.
- Hematogenous – when cancer cells travel through the blood vessels to other organs and tissues.
- Lymphogenous – this is when the spread of the tumor occurs through the lymphatic vessels. Tumors, which are formed in the head or neck, most often metastasize through the lymphatic system.
Cancers of the head and neck often affect the lymph nodes. Cancer frequently targets a node in the vicinity of the internal jugular vein. The likelihood of further spread of cancer cells through the blood vessels, to a large extent, depends on the number of lesions and the location of lymph nodes in the neck area. The risk of metastasis increases when there are lesions in lymph nodes of the lower neck region.
The clinical presentation of tumors in the head and neck area depends on the tumor location and stage of the disease. Most often, these symptoms are observed:
- Presence of oral and/or nasal mucosa defects
- Skin defect;
- Enlargement of regional lymph nodes;
- Difficulty in swallowing;
- Weakness, loss of appetite, exhaustion and fever.
General examination plays an important part in the diagnostics of head and neck cancers. Based solely on the examination, experienced oncologists already might have a reason to suspect the diagnosis. Next, the patient is asked to undergo a series of additional studies, usually including imaging.
The main method for head and neck cancer evaluation is a biopsy of the tumor, followed by histological examination of the extracted tissues.
Treatment tactics depend on how advance the malignant processes are, and decided upon individually for each patient . Doctors take into the account the results of medical evaluation, age, general health condition of the patient, and also presence or absence of concomitant somatic pathology. Treatment of malignant tumors in head and neck region usually includes surgery, radiotherapy and chemotherapy. Most often those methods are used in combination. Generally, treatment starts with radiation therapy, which focuses on reducing the size of the tumor. Next phase is surgical removal of cancer growth. The final stage of the cancer treatment is chemotherapy course, consisting of several cycles.
External beam radiation therapy is a method widely used in treatment, allowing to direct a focused beam of radiation directly on the tumor. The radiation is generated by a linear accelerator and focused on the pathological zone. Radiation kills abnormal cells, while the impact on normal tissues and organs remains minimal. Modern radiotherapy shows high efficiency in the treatment of head and neck cancer. This method of treatment used by oncologists in cancer treatment centers worldwide.
There is also another, newer method of radiotherapy using computerized linear accelerators, called intensity-modulated radiation therapy (iMRT). This technology allows the specialists to send a radiation beam directly into the tumor. It is configured in a special advanced way, which allows them to aim specifically at cancer cells. based on the tumor’s 3D representation, without affecting healthy tissue. The effect on healthy cells is minimal.
Before the radiotherapy can be conducted, the patient is evaluated by the radiation oncologist, studying all available information about the patient’s condition, and taking into account the individual characteristics of the disease to offer the best options for treatment. Also, the patient undergoes examination by a pathologist and surgeon.
Before the radiation therapy begins, specialists conduct its simulation using a CT machine, that allows to calculate accurately the radiation dose and treatment duration. Then, within 2 or 3 days, radiotherapy begins. It can be conducted 1 or 2 times a day, five times a week. Radiotherapy can last for a month or two, depending on the requirements of the patient’s treatment process. The first few treatments last about an hour, and subsequent sessions are held for several minutes. During the treatment process the patient does not feel any pain. Side effects of radiation therapy usually begin not earlier than on the second week of treatment progress.
Doctors responsible for the treatment always warn of possible side effects, that occur depending on the location of the tumor, as well as on the degree of spread of the malignant process and therapy’s intensity.
In modern oncology new methods, protocols and drugs are constantly being introduced into the battle against head and neck cancer. Doctors also combine old methods with the new ones to achieve maximum effect, for example combination of chemo-radiotherapy with immunotherapy in growing tumors. In recent years, new effective drugs were developed that increase sensitivity of malignancies to radiotherapy.
Due to the fact that many patients with head and neck cancer treatment begin treatment on advanced stages, the prognosis is not always favorable. The average five-year survival rate is 45-55%.