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Cancer Basics: Home

What Is Cancer?

Cancer begins in your cells, which are the building blocks of your body. Normally, your body forms new cells as you need them, replacing old cells that die. Sometimes this process goes wrong. New cells grow even when you don't need them, and old cells don't die when they should. These extra cells can form a mass called a tumor. Tumors can be benign or malignant. Benign tumors aren't cancer while malignant ones are. Cells from malignant tumors can invade nearby tissues. They can also break away and spread to other parts of the body.

Cancer is not just one disease but many diseases. There are more than 100 different types of cancer. Most cancers are named for where they start. For example, lung cancer starts in the lung, and breast cancer starts in the breast. The spread of cancer from one part of the body to another is called metastasis. Symptoms and treatment depend on the cancer type and how advanced it is. Most treatment plans may include surgery, radiation and/or chemotherapy. Some may involve hormone therapy, immunotherapy or other types of biologic therapy, or stem cell transplantation.

Source: MedlinePlus - Cancer

Helpful Websites

Materials at the Cancer Resource Library

Videos

What is cancer? - Macmillan Cancer Support

This cancer information animation shows how cancer starts in our cells. Abnormal cells can keep dividing and making more abnormal cells which form a lump called a tumor.

When the Doctor Says Cancer

In this video, Dr. Jonathan Berek and patient advocate Angela Lee discuss steps to take after a cancer diagnosis, including coping with the news, locating an oncologist, and finding support.

Recommended Apps

Cancer.Net Mobile

Cancer.Net Mobile includes up-to-date guides on more than 120 types of cancer, with information about treating cancer, managing side effects, managing the cost of care, and living with cancer. Use interactive tools to keep track of questions to ask doctors and record voice answers. Save information about prescribed medications, including photos of labels and bottles. Track the time and severity of symptoms and side effects.

Cancer.Net Mobile is free and available for iOS (iPhone and iPad) and Android

Resources provided by the Cancer Resource Library are for informational purposes only. The information in these materials may or may not apply to your specific condition, and should not be construed as medical advice. We strongly encourage you to consult your healthcare provider to review anything you learn through these resources.

Ridley-Tree Cancer Center provides comprehensive cancer treatment and support programs for patients and families. We are recognized for medical excellence, a strong clinical research program, and a multidisciplinary approach to cancer prevention.

Cancer Resource Library | 540 West Pueblo Street, Santa Barbara, CA 93105 | (805) 563-5807 | library@ridleytreecc.org | www.ridleytreecc.org