Salivary gland cancer is a term used to interpret the uncontrolled proliferation of malignant cells in the salivary glands. The salivary glands are placed in the mouth and throat and their main function is to produce saliva or spit. This saliva is the primary component of digestion as it mixes with the food eaten to form a bolus and then assists in breaking it down into smaller pieces.
Additionally, they retain moisture in the mouth and aid in keeping the teeth healthy. Every individual has three pairs of major salivary glands under and behind the jaw, mainly; Parotid, Sublingual and Submandibular. There are many other tiny salivary glands in the lips, inside the cheeks, and throughout the mouth and throat.
Salivary gland cancers are quite rare and contribute to only 1% of tumours affecting head and neck cancers. The most widespread types of salivary gland cancer are mucoepidermoid carcinoma and adenoid cystic carcinoma.
Identical to any other form of cancer or tumorous growth, there is no laid path for salivary gland cancers, but certain pieces of research indicate that when there is a genetic mutation in the DNA of the salivary gland cell, it rapidly turns the normal, healthy cells into abnormal ones. These abnormal cells don't thrive and multiply like the normal ones, rather they evolve and multiply uncontrollably without perishing, eventually assembling to form a cancerous growth.
These cancerous cells gradually attack the nearby healthy cells and tissues and become metastatic by getting detached from the initial tumour to slowly spread to other parts of the body.
Specific causative factors that may increase the incidence of salivary gland cancers include:
Age: Salivary gland cancers are more widespread in people aged 55 or above
Gender: This form of cancer is diagnosed more in men than in their female counterparts
Exposure To Radiation: People who are subjected to radiation therapy to the head or neck have a higher risk of salivary gland cancer
Professional Risk: People who are working in certain occupations, like rubber products manufacturing, asbestos mining, plumbing, and leather work are more susceptible to salivary gland cancer
Unhealthy Lifestyle Habits: Constant smoking or extreme intake of tobacco or alcohol aggravates the risk of salivary gland cancer
Viral Infection: The common HMV or Human Papillomavirus makes a person more vulnerable to getting this type of cancer
Without any proper symptoms in the initial stage, salivary gland cancers are quite difficult to diagnose. The distinct symptoms mainly develop as the tumours gradually grow in size and number. Some of these characteristic manifestations of salivary gland cancer include:
- Presence of a lump or swelling on or near the jaw or in the neck or mouth
- Sudden numbness in a part of the face
- Muscle weakness on one or both sides of the face
- Development of a sore lesion in the mouth
- Loosening of teeth
- Pain or numbness of the teeth
- Continual pain in the area of the salivary gland
- Difficulty in swallowing food or water
- Difficulty in talking
- Intense pain while opening the mouth widely
- Bleeding from the mouth
On partly confirming the malignancy of the salivary gland cells, the doctor may perform a detailed physical examination by feeling your jaw, neck and throat for lumps or swelling. He or she then acknowledges the past medical history, and exposure to radiation or other carcinogens and performs the following diagnostics:
- Imaging procedures like CT-Scan, MRI-Scan, and Positron Emission Tomography (PET) to deduce the size and location of the salivary gland tumour
- Biopsy of a sample of salivary gland tissue to infer what category of cells are involved in the tumour and whether the cells are malignant
Stages Of Salivary Gland Cancer
Stage I: Development of a 2cm or smaller tumour without metastasizing up to the lymph nodes
Stage II: Size of the tumour, varying from 2-4 cm without spreading to the lymph nodes
Stage III: The size of the tumorous mass becomes more than 4cm but it still hasn't spread to the lymph nodes or has spread to only one lymph node but not to other parts of the body
Stage IV: Termed as the last or advanced stage of cancer when the tumours become quite huge and the cancer cells have metastasized onto the surrounding healthy tissues and other parts of the body
Just like any other form of carcinoma, salivary gland cancer is usually treated depending on the type of cells involved, the location of the tumour and the particular stage of cancer. The current treatment options involve:
- Surgery: This involves removing a portion of the affected salivary gland or removing the entire salivary gland or removing just the lymph nodes in the neck and finally reconstruction of the face
- Radiation therapy
- Palliative Care