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What is Cancer?

Cancer is a group of more than 100 different diseases. It occurs when cells become abnormal and keep dividing and forming more cells without control or order.

All organs of the body are made up of cells. Normally, cells divide to produce more cells only when the body needs them. If cells divide when new ones are not needed, they form a mass of excess tissue, called a tumor.

Not all tumors are cancer – they can be benign (not cancer) or malignant (cancer). A few types of cancer, such as blood cancers, do not form tumors at all. The cells in malignant tumors can invade and damage nearby tissue and organs.

Cancer cells can also break away form a malignant tumor and travel through the bloodstream or the lymphatic system to form new tumors in other parts of the body. The spread of cancer is called metastasis.

To determine how far a cancer has spread, your cancer care team uses a process of analysis known as staging. The stage of your cancer impacts your treatment and the prognosis for recovery.

A number of different staging systems can be used to classify tumors. The TNM staging system assesses tumors in three ways:

  • Size of the primary tumor (T)
  • Whether it has spread to lymph nodes (N)
  • Whether it has spread (metastasized) to other organs (M).

Once the T, N, and M are determined, a number of I, II, III, or IV is assigned, with stage I being early stage and IV being advanced. In general, the lower the number, the less the cancer has spread. A higher number, such as stage IV, denotes a more serious case. Your doctor will review your test results and tell you the stage of your cancer.

Cancer is treated with surgery, radiation therapy, chemotherapy, hormone therapy, or biological therapy. Your doctor may use one or a combination of methods. The type treatment depends on the type and location of the cancer, whether the disease had spread, your age and general health, and other factors.

Side effects of radiation (usually temporary) can include mild skin irritation (similar to sunburn), nausea, bladder irritation, diarrhea, or fatigue. Side effects of chemotherapy can include diarrhea, nausea, loss of hair, rashes on hands and feet, mouth sores and fatigue. Most of these side effects disappear once treatment ends. Be sure to ask your physician for specific information on side effects of your cancer treatment.

Can cancer be prevented?

Many types of cancer can be prevented through healthy choices such as not using tobacco, avoiding harmful sunrays, and choosing foods with less fat and more fiber. Scheduling regular check-ups and self-exams can reveal cancer at an early stage when treatment is most likely to be effective.

What is a biopsy?

A biopsy is the microscopic examination of a surgically removed piece of tissue. A biopsy determines whether cancer cells are present. A biopsy is the most important procedure in diagnosing cancer.

What are calcifications?

Calcifications are small calcium deposits in the breast, detected from a mammography. Microcalcifications are tiny specks of calcium that can be found in an area of rapidly dividing cells. When many of these are seen in one area, they are called a cluster and may indicate a small cancer. About half of the cancers detected by mammography appear as a cluster of microcalcifications, the other half appears as lumps. Macrocalcifications are coarse calcium deposits that are found in about half of all women over age 50 and are associated with benign conditions. They are often seen in both breasts and are most likely due to aging or old injuries.

What is metastasis?

Metastasis refers to the spread of cancer cells to distant areas of the body by way of the lymph system or bloodstream.

What are risk factors for cancer?

Unprotected exposure to strong sunlight is a risk factor for skin cancer and smoking is a risk factor for cancers of the lungs, larynx, mouth, throat, esophagus, kidneys, bladder and several other organs. A diet high in animal fats is a risk factor for several types of cancers, including stomach, colorectal, breast and prostate cancer.


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You are Unique

At St. John Providence Health System, we know that you’re a unique individual and not just a condition or a list of symptoms. We treat the whole person.

Get in touch with us so we can learn about you and give you the help you need for your individual situation.

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