Head and neck cancer includes cancers of the mouth, nose, sinuses, salivary glands, throat, and lymph nodes in the neck. Most begin in the moist tissues that line the mouth, nose, and throat. Symptoms include
- A lump or sore that does not heal
- A sore throat that does not go away
- Trouble swallowing
- A change or hoarseness in the voice
Head and neck cancers are twice as common in men. Using tobacco or alcohol increases your risk. In fact, around 75 percent of head and neck cancers are linked to tobacco use, including smoking and smokeless tobacco. Infection with HPV is a risk factor for some head and neck cancers.
To diagnose head and neck cancer, your doctor will do a physical exam and diagnostic tests. You will have a biopsy, where a sample of tissue is taken out and examined under a microscope. It is the only test that can tell for sure if you have cancer.
If found early, these cancers are often curable. Treatments may include surgery, radiation therapy, chemotherapy, or a combination. Treatments can affect eating, speaking or even breathing, so patients may need rehabilitation.
Central Nervous System Cancer
Secondary tumors are those that develop in the brain as a result of the spread of cells from a malignant tumor that can be located in any organ of the body.
The location where a cancer initially originates is called the primary tumor. When malignant cells spread out to other organs, they are implanted and grow in them as a secondary tumors or metastases. The cells that form these metastases are similar to those of the primary tumor.
Secondary brain tumors are also called brain metastases.
Cancers that most often produce brain metastases are lung, breast, colon, kidney, bladder, and melanoma cancers.
Types of primary tumor
Primary CNS tumors are named based on the cell in which they originate. The most frequent are the following:
• Gliomas: originate from the supporting cells of the nervous tissue, called glial cells. More than half of the CNS tumors are gliomas. They are classified according to the speed of division and the appearance of the cells when viewed under a microscope. Gliomas are divided into 4 degrees:
• Grade 1 and 2: also called low-grade gliomas. They are made up of cells that divide slowly and are usually less aggressive.
• Grade 3 and 4: or high-grade gliomas. In both cases their cells divide more rapidly and are higher malignancy than grade 1 and 2 gliomas.
Treatment and prognosis depend fundamentally on the degree of the tumor.
Types of gliomas
Grade 3 astrocytomas are also called anaplastic astrocytomas and grade 4 tumors are called multiform glioblastomas (accounting for 30% of all adult brain tumors). Both are the most common glial cell tumors in adults and come from astrocytes.
They come from the oligodendrocytes, which are the cells responsible for the production of the tissue that covers the different nerves (myelin, which is responsible for facilitating the conduction of nerve impulses between nerve fibers). They are slower growing than astrocytomas.
• Mixed Glioma:
It is constituted by several types of cells, being the most frequent the oligo-astrocytomas.
They are rare tumors, accounting for 9% of all brain tumors. It is more common in childhood and adolescence. They come from the cells that line the ventricles and the medullary canal. Through the cerebrospinal fluid can spread throughout the central nervous system. They are divided into low grade or benign ependymomas, which are the most frequent or high grade or anaplastic ependymomas.
It is the second most frequent brain tumor in the child, although 30% appears in adults. Its usual location is in the cerebellum. Medulloblastoma is an invasive, rapidly growing tumor that often spreads to other parts of the central nervous system.
• Meningioma or primitive neuroectodermal tumor:
It is a tumor, usually benign that develops from the meninges (tissue that covers the central nervous system). It accounts for 20% of all primary brain tumors and is most commonly located in the cerebral hemispheres, although they may also occur in the spinal cord.
The symptoms of this tumor are secondary to the compression of healthy brain tissue, rather than an invasion of it.
It is a benign congenital tumor and appears mainly in childhood and adolescence.
They grow in an area of the brain called the Turkish saddle, where the pituitary gland is placed, and very close to the optic nerves. Symptoms are usually due to increased intracranial pressure.
It accounts for 2% of all primary tumors of the central nervous system, being more frequent in young adults (between the 2nd and 4th decade). They are located at the base of the skull and at the end portion of the spinal cord. This tumor is usually benign, although it usually invades bone by contiguity.
• Primary lymphoma of the central nervous system:
Its most frequent location is in the hemispheres of the brain. They are tumors of the lymphatic system, which is part of the body’s immune system, so they usually appear in immunosuppressed patients (patients undergoing organ transplantation or with AIDS).
• Adenomas of the pituitary gland:
The pituitary gland produces a series of hormones that are in charge of controlling the hormonal production of the other glands of the body.
Pituitary adenomas are benign, slow-growing tumors and account for 8% of all primary CNS tumors.
These tumors are classified into secretory and non-secretory tumors depending on their ability to segregate or secrete a particular hormone.