Principles of Oncology Flashcards
G1 Checkpoint
- To initiate apoptosis if DNA is damaged beyond repair
G2 Checkpoint
- To prevent starting of mitosis till DNA has replicated
M Checkpoint
- To stop mitosis till chromosomes are properly aligned
Smallest clinically detectable tumor
- 10^9 cells (1gm)
*30 population doublings (2^30)
Anaplasia
- Lack of differentiation
*characteristic of MALIGNANT tumors; although most malignant tumors are monoclonal in origin, by the time they become clinically evident their constituent cells are highly heterogenous
*benign tumors are well differentiated
American Joint Committee on Cancer Staging system
- TNM system
*T- tumor number and size
*N- regional lymph node invasion
*M- metastasis
Most prominent sites of metastases
- Liver and lung
*portal area drainage flows to the liver
*all caval blood flows to the lungs
Cancers with preferences
- Breast carcinoma
*prefer bone and brain metastasis
- Bronchogenic carcinomas
*prefer adrenals and brain
- Prostate cancer
*prefer bone
*Skeletal and muscles and spleen are rarely the metastasis sites*
Anaplerosis vs. Cataplerosis
- Anaplerosis: synthesizing and replenishing the intermediates of the TCA cycle
- Cataplerosis: intermediates escaping from the TCA cycle and synthesizing other molecules
- In cancer cells, cataplerosis>anaplerosis
- Mobilizing proteins and fat to feed cancer cells
- Cachexia
Carcinomas
- Tumors derived from the epithelial cells
Sarcomas
- Tumors from the connective tissue
Leukemias
- Tumors derived from blood cells
Do all malignant cancers metastasize?
- Most malignant cancers can metastasize
- Eceptions: gliomas (brain cancer) and basal cell carcinoms of the skin
Cancer trends between 1930 and 2005
- Lung cancer increased dramatically
Diet, physical inactivity and obesity responsible for what % of cancer deaths
- 30-35%
