Cancer

• Proto oncogenes


  Cells that promote growth
• Mutation in proto oncogenes

  Cells become independent to regulatory mechanisms leading to uncontrolled growth
• Tumor suppressor genes

  Cells that suppress growth
• Mutation in tumor suppressor genes

  Will lose its function - no stopping the tumor growth
• Cancer development stages

  • Initiation
  • Promotion
  • Progression
• Initiation stage

  1. Mutation in cell’s genetic structure

  2. Causes cells to die

  3. Repair itself

  4. Replication, passing genetic mutation onto daughter cells
• Promotion stage

  1. Proliferation

  2. Presence of promotion factors that worsen cancer

  3. Cancer should be a mass to become clinically evident
• Progression stage

  1. UP tumor growth

  2. UP spreading to other sites
• Benign tumors

  • Slow growth
  • Well-differentiated
  • Don't spread
• Malignant tumors

  • Rapid growth
  • Poorly differentiated
  • Metastasize
• Main sites of metastasis

  • Lungs
  • Liver
  • Brain
  • Bones
  • Adrenals
• Once cancer enters main sites of metastasis it is harder to control
• Cancer classification

  • Anatomical site
  • Histological analysis
  • Extent of disease
• Localized cancer

  Stage 1/2
• Metastasized cancer

  Stage 3/4
• Local effects of tumors

  • Occlusion
  • Ulceration
  • Pain
  • Infarction
• Systemic effects of tumors

  • Weight loss
  • Bleeding
  • Anemia
  • Infection
• Pain in cancer: Little to no pain during early stages
• Causes of pain in cancer

  • Direct pressure
  • Obstruction
  • Invasion
  • Tissue destruction
  • Infection
  • Inflammation
• Pain can be at the tumor or due to metastasis
• Bone metastasis causes pain
• Brain tumors cause headaches
• Fatigue in cancer doesn't improve with rest
• Causes of fatigue in cancer

  • Anemia
  • Bleeding
  • Infection
  • Weight loss
• Cachexia

  Significant weight loss and inflammation, and weight loss as a result of skeletal muscle and body fat loss
• Pancytopenia

  Most common in bone marrow, lymphatic cancers
• Anemia


  Related to chronic bleeding, malnutrition, and cancer in blood forming organs
• Tumor invasion of bone marrow

  Causes leukopenia
• Anemia is more common in colorectal, genitourinary, pancreatic, gastric, and upper intestinal cancers
• Infection can be caused by

  Ulceration and obstruction
• Paraneoplastic syndromes


  Body’s attempt to destroy tumor causes unintended damage
• Unintended damage from paraneoplastic syndromes

  • Fever
  • High blood pressure
  • Low blood pressure
  • Edema
• WBC: early sign -> few hours to days -> notice early because lifespan is very short
• Platelets: 10 days - how long you will see the effects
• RBC: 120 days -> later sign
• Lymphoma

  Cancer of the lymphatic system that starts anywhere lymph is found
• Main types of lymphoma

  • Hodgkin’s lymphoma
  • Non-Hodgkin’s lymphoma
• Hodgkin’s lymphoma

  • Characterized by proliferation of Reed-Sternberg cells
  • Rare
  • 80% of patients will be cured
  • More common in men
  • Ages 15-30 years old and less than 55 years old
  • Often originates in cervical nodes but sometimes inguinal and axillary nodes
• Clinical manifestations of Hodgkin’s lymphoma

  • Weight loss
  • Fatigue
  • Weakness
  • Fever
  • Night sweats
• Risk factors for Hodgkin’s lymphoma

  • Occupational toxins
  • Genetic predisposition
  • HIV