L3.4.3: Causes & Risk Factors

• Cancer is Idiopathic

  ○ The main cause is unknown
• Risk Factors/Causes

  ○ Heredity / Family hx (history)

  ○ Exposure to Carcinogens – chemicals that cause cancer

  ■ Chemicals & environmental agents

  ■ Benzopyrene (tobacco smoke, vehicle exhaust, grilled or charred food)

  ■ Nitrosamines (processed meats)

  ■ Radiation (medical imaging and cancer treatment (secondary type of cancer is developed due to too much radiation as treatment)

  ■ Viruses (HPV/Human Papillomavirus causes breast cancer and Hepatitis B–causes liver cancer)
• Types of Cancer

  • Lung Cancer
  • Oral Cancer
  • Laryngeal Cancer (Respiratory)
  • Bladder Cancer
  • Renal Cancer (Kidney Cancer)
  • Cervical Cancer
  • Esophageal Cancer (Esophagus; Gastrointestinal)
  • Breast Cancer
  • Colon Cancer
  • Prostate Cancer
  • Liver Cancer
  • Skin Cancer
  • Uterine or Endometrial Cancer
• Lung Cancer

  ● Leading cancer in males.

  ● Tobacco Use:

  ○ Cigarettes

  ○ Cigars

  ○ Chewing tobacco

  ○ Snuff
• Lung Cancer

  ● Radiation exposure

  ● Second-hand smoke (more potent than first-hand smoking)
• Oral Cancer

  ● Tobacco use (Top 1 reason)

  ○ Cigarette

  ○ Cigar

  ○ Pipe

  ○ Smokeless Tobacco
• Oral Cancer

  ● Excessive alcohol use

  ● Chronic irritation (ill-fitting dentures → infection → bleeding)

  ● Vitamin A deficiency
• Laryngeal Cancer (Respiratory)

  ● Tobacco use

  ○ Cigarette

  ○ Cigar

  ○ Pipe

  ○ Smokeless tobacco

  ● Poor nutrition

  ● Alcohol
• Laryngeal Cancer (Respiratory)

  ● Weakened immune system

  ● Occupational exposure to wood dust, paint fumes

  ● Gender: 4-5x more common in men

  ● Age: more than 60 yrs old
• Bladder Cancer

  ● Tobacco use

  ○ Cigarette

  ○ Cigar

  ○ Pipe

  ○ Smokeless Tobacco
• Bladder Cancer

  ● Occupation Exposure: dyes, solvents

  ● Chronic bladder inflammation (continuous inflammation leads to the development of cancer)
• Renal Cancer (Kidney Cancer)

  ● Tobacco use

  ○ Cigarette

  ○ Cigar

  ○ Pipe

  ○ Smokeless Tobacco (increase risk by 40%)

  ● Obesity
• Renal Cancer (Kidney Cancer)

  ● Proper Diet: well-cooked meat (In kidney problems, proteins are restricted)

  ● Occupational Exposure: Asbestos and Organic Solvents

  ○ Asbestos – Age 50-70 y/o
• Cervical Cancer

  ● Tobacco use

  ○ Cigarette

  ○ Cigar

  ○ Pipe

  ○ Smokeless Tobacco
• Cervical Cancer

  ● Human Papillomavirus Infection (Contributors to genital warts)

  ○ cancer-causing virus that have vaccines

  ● Chlamydia Infection

  ● Diet: Low in fruits and Vegetables

  ● Family hx of cervical cancer
• Esophageal Cancer (Esophagus; Gastrointestinal)

  ● Tobacco use

  ○ Cigarette

  ○ Cigar

  ○ Pipe

  ○ Smokeless Tobacco
• Esophageal Cancer (Esophagus; Gastrointestinal)

  ● Alcohol

  ● Gender: 3x more common in men

  ● Diet: Low in fruits and Vegetables
• Breast Cancer

  ● Leading cancer in females

  ● Early menarche / Late Menopause

  ○ Exposure to hormones

  ■ Too much exposure to hormones of estrogen and progesterone can cause hormones
• Breast Cancer

  ● Physical inactivity

  ○ High physical activity = High levels of estrogen = low risk of cancer

  ● Family hx

  ● Alcohol consumption

  Mastectomy is surgery to remove a breast.
• Colon Cancer

  ● Personal/family hx of polyps

  ○ growth inside the digestive tract (in the colon/large intestine)
• Colon Cancer

  ● Diet: High fat or Low fiber

  ● Hx of ulcerative colitis (development of lesions and craters in the colon)

  ● Age: more than 50 years old
• Prostate Cancer

  ● Common in men

  ○ Prostates are only found in men.

  ● Enlarged Prostate = Urinary Obstruction
• Prostate Cancer

  ● Urethral Obstruction

  ○ Urinary frequency

  ■ Not completely emptied

  ○ Nocturia (urination at night)

  ○ Decrease in stream

  ○ Post void dribbling

  ■ Small amount of urine that leaks out of the urethra after a complete urination.
• Prostate Cancer

  ● Screening of Prostate Cancer

  ○ Digital Rectal Examination (DRE)

  ■ kakapain/physical examination

  ○ Prostate Specific Antigen (PSA)

  ■ Laboratory test

  ■ High PSA level = Risk of Prostate Cancer
• Liver Cancer

  ● Viral Hepatitis (Hepatitis B)

  ● Liver Cirrhosis: Scarring of the lining of the liver (too much alcohol)

  ● Long-term exposure to aflatoxin (aflatoxicosis → jaundice → affected liver)
• Skin Cancer

  ● Unprotected exposure to strong sunlight

  ● Higher Sun Protection Factor (SPF) = Longer protection from sun

  ○ SPF# x 20 (sun time) = # of minutes of sun time
• Skin Cancer

  ● Females have less risks of skin cancer due to their high number of melanocytes.

  ● Fair Complexion (less melanin) (melanin protects DNA from getting damaged)

  ● Occupational exposure
• Uterine or Endometrial Cancer

  ● Estrogen replacement therapy

  ○ A risk factor

  ○ Done by menopausal women

  ○ Intake of synthetic estrogen

  ● Early menarche or Late Menopause
• PRIMARY PREVENTION OF CANCER

  1. Smoking Cessation

  2. Proper Diet / Nutrition

  3. Alcoholic Beverages in Moderation

  4. Avoid / Control Obesity

  5. Early Diagnosis

  ● If stage 3, incurable