Cancer- Basics, terminology, Types and staging

"Where there is life, there is cancer. Although the types of cancer and their inci- dence (the number of new types diagnosed each year) may vary by geography, sex, race, age, and ethnicity, cancer exists in every population and has since ancient times."
"The name itself comes from the Greek word for crab, used by Hippocrates to describe the appearance of the most common type of cancer, carcinoma."
"Oncology is the study of tumors, both benign (noncancerous) and malignant (cancerous). An oncologist is a specialist in the diagnosis, treatment, and pre- vention of tumors."
"Current research suggests that there is no single cause of cancer. Radiation, bacteria, viruses, genetics, diet, smoking (or exposure to tobacco smoke), alcohol, and other factors all contribute to the development of cancer termed carrion (Cancer)- genesis (production or origin)."

"Each of these factors is instrumental in disrupting the normal balance of cell growth and destruction within the body by causing a mutation (mutation (mut/a = change -tio) in the origin DNA of cells "

"Once this mutation takes place, a process of uncon-trolled cell growth may begin. It is important to note that the cancer cells that replace normal cells no longer function to keep the body working. The only mission of cancer cells is to reproduce. Apoptosis is the process of, the body’s normal restraining function to keep cell growth in check."

See the breakdown meaning of words below:

apoptosis (apo- = away from -ptosis = falling)
hyperplasia (hyper-plasia = excessive -plasia = condition of formation)
dysplasia (dys- = abnormal -plasia = condition of formation)

"Cancers are capable of destroying not only the tissue in which they originate (the primary site), but also other tissues, through the process of metastasis, the spread of cancer. Metastasis ("meta- = beyond, change -stasis = controlling, stopping") can occur by direct extension to contiguous organs and tissues or to distant sites through blood".

"All cancers are neoplasms (new growths), but not all neoplasms are cancerous. Cancerous tumors are termed malignant, whereas noncancerous tumors are termed benign."

"Carcinomas: Approximately 80% to 90% of malignant tumors are derived from the outer (ectodermal- Outer Skin) and inner (endodermal- within skin) layers of the embryo that develop into epithelial tissue that either covers or lines the surfaces of the body."

"If derived from an organ or gland, it is an adenocarcinoma; if derived from squamous "epithelium, it is a squamous cell carcinoma. Examples include gastric
adenocarcinoma and squamous cell carcinoma of the lung.

Sarcomas are derived from the middle (mesodermal) layer, which becomes connective tissue (bones, muscle, cartilage, blood vessels, and fat). Most end in the suffix -sarcoma. Examples include osteosarcoma, chondrosarcoma, hemangiosarcoma, mesothelioma, and glioma.

Lymphomas develop in lymphatic tissue (vessels, nodes, and organs, including the spleen, tonsils, and thymus gland). Lymphomas are solid cancers and may also appear outside of the sites of lymphatic organs in the stomach, breast, or brain; these are called extranodal lymphomas. All lymphomas may be divided into two categories: Hodgkin lymphoma and non-Hodgkin lymphoma.

• Leukemia is cancer of the bone marrow. An example is acute myelocytic leukemias.

• Myelomas arise from the plasma cells in the bone marrow. An example is multiple myeloma.

• Mixed tumors are a combination of cells from within one category or between two cancer categories. Examples are teratocarcinoma and carcinosarcoma.

"Grading is the first means of affixing a value to a clinical opinion of the degree of dedifferentiation (anaplasia) of cancer cells, or how much the cells appear different from their original form. Healthy cells are well differenti- ated; cancer cells are poorly differentiated. The pathologist determines this dif- ference and assigns a grade ranging from I to IV. The higher the grade, the more cancerous, or dedifferentiated, is the tissue sample. Grading is a measure of the cancer’s severity.
The other means of determining the size and spread of the cancer from its original site, which is called staging. A number of systems are used to describe staging. Some are specific to the type of cancer; others are general systems. If staging is determined by various diagnostic techniques, it is referred to as clini- cal staging. If it is determined by the pathologist’s report, it is called "pathologic staging. An example is TNM staging. In this system, T stands for the size of the tumor, N stands for the number of lymph nodes positive for cancer, and M stands for the presence of distant metastasis (meh TAS tuh sis)." more