Learning about Cancer
The word cancer describes many
diseases, but all cancers are caused by
cells that grow quickly and may spread
to other parts of the body. In normal
body tissues, cell growth and death
are kept in balance. This is the body’s
natural cycle — to get rid of old cells
with new ones. Cancer cells change this
cycle.
Cells that grow fast may form lumps or
masses of tissue called tumors. Some
tumors grow quickly, others slowly. All
tumors will increase in size because new
cells are being made faster than old cells
die.
Metastasis
• Occurs when cancer cells travel
through blood and lymph fl uid from
the tumor (called the primary site) to
another part or parts of the body
• Example — prostate cancer that has
metastasized to the bone is not bone
cancer, but rather prostate cancer that
has spread to the bone
Common
Types of Cancer
Carcinomas
Benign Tumors
• Are named for body parts
• Are the most common types of
cancers
• Include lung, colon, breast, and
ovarian cancers
• Are not cancer
• Are made up of cells that look like
healthy tissue cells
• Remain in tight groups
• Do not invade nearby healthy tissues
and organs
• Include fatty tumors called lipomas
Sarcomas
• Develop in cells found in the support
tissues of the body
• Include cancer of the bone, cartilage,
fat, and muscle
Malignant Tumors
• Are made up of cancer cells
• May develop from normal cells, but
over time and through many steps
become unhealthy cancer cells
• May invade nearby healthy tissues and
organs
• May spread to other parts of the body
Lymphomas
• Begin in lymph nodes and tissues of
the body’s immune system
• Include cancers such as Hodgkin’s
and non-Hodgkin’s lymphomas
Leukemias
• Begin in immature blood cells that
grow in the bone marrow
• Grow quickly and collect in large
numbers in the bloodstream
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