Understanding+Cancer

=What is Cancer?= Cancer is the uncontrollable growth of cells. When there is a cluster of these cells, it's called a tumor.

[|Beast Cancer Site]

Some Basic Background Information:

 * **Tumor suppressor gene:** acts as a “brake,” and regulates the checkpoints (P53, BRCA, MEN1)
 * **Proto-oncogenes:** makes body produce growth factors (RAS, MYC)
 * If not working properly/mutated…can rapidly produce GF or may stop division of cells
 * **Benign tumor:** grade 1
 * **Malignant tumor:** (abnormal cells) can cause/damage nearby tissue/spread (__metastasize)__


 * **Description of cancer cells:**
 * Non-uniform shape
 * Nuclei are much bigger in size (sometimes multiple nucleoli)
 * Small amounts of cytoplasm
 * Multiple nuclei

The Cell Cycle:
Cell Cycle Animations
 * G0:** Cell carries out normal functions not dividing
 * G1**: Another stage of cell growth
 * S:** (Synthesis) Replicates the DNA
 * G2**: Growth: more cytoplasms/organelles are made
 * M**: (Mitosis) cell splits, nuclear division and cytokinesis. [__fastest stage]__
 * Interphase: G1, S, G2**
 * Checkpoints: **
 * **Purpose of Checkpoints**: make sure DNA is replicated, make sure DNA matches properly (not mutated), make sure each side receives the same amount of DNA
 * **If checkpoints do not work**: cell might grow uncontrollably even if it is mutated. When checkpoints fail and produce mutated cells it’s called cancer.
 * **What causes cells to divide**: presence of growth factors signals chemicals
 * **What causes cells to stop**: signals within cells or environment
 * **Apoptosis:** programmed cell death of damaged cells
 * **UV Radiation:** can cause mutation in tumor suppressor genes/proto-oncogenes



=**__Interpreting Pathology Reports__**=
 * **Clinical history**: see what has already been done, what treatments have been tried
 * **Gross Description**: look at size mainly
 * **Description**: find as much information as possible here describing the cancer
 * **Specimen type**: where it was taken from
 * **Tumor size**: helps in diagnosis of stage
 * **Histological grade: shows difference between cancerous cells and healthy cells (3 grades)**
 * **Stage**: 0-IV
 * **Number of nodes examined**: Shows how much it has spread
 * **Number of positive nodes**: more important, shows how many lymph nodes contain cancer cells. Large number of positive may mean cancer is more serious
 * Under arm: **auxiliary nodes**
 * Within Breast: **sentinel nodes**
 * **Lymphovascular invasion:** bloodstream=bad. If cells invade blood of lymphatic tissue the cancer has a higher risk of returning after tumor is removed.
 * Cell is **hormone positive** if it has many **ER or PR receptors**(rated 0-3)
 * ER AND pr POSITIVE RESPOND WELL TO HORMONE THERAPIES
 * **HER-2/neu**is involved in normal cell growth. If it has too many copies of HER2 it tends to grow very fat.
 * HER2/neu positive respond well to __biological therapy__ which uses antibodies