Cancer

Dr. Raid Jastania

Cancer

• In the US: 1.3 million new cancer cases in 2002

• >500,000 death of cancer

• Increase cancer death in men due to lung cancer

• Drop cancer death in women due to drop in gastric, uterine and colon cancer

Cancer: Geographic and Environmental Factors

• In a study 65% of cancer is due to environmental factors

• 26-42 % due to inherited factors

– Breast cancer common in the US– Stomach cancer common in Japan– Liver cancer common in Africa

2007 Estimated US Cancer Cases2007 Estimated US Cancer Cases

*Excludes basal and squamous cell skin cancers. Source: American Cancer Society, 2007.

Men766,860

Women678,060

•26% Breast

•15% Lung & bronchus

•11% Colon & rectum

•6% Uterine corpus

• 4% Non-Hodgkin lymphoma

•4% Melanoma of skin

• 4% Thyroid

• 3% Ovary

• 3% Kidney

•3% Leukemia

•21% All Other Sites

Prostate 29%

Lung & bronchus 15%

Colon & rectum 10%

Urinary bladder 7%

Non-Hodgkin4% lymphoma

Melanoma of skin 4%

Kidney 4%

Leukemia 3%

Oral cavity 3%

Pancreas 2%

All Other Sites 19%

KSA-CIR 2003KSA-CIR 2003

Cancer

• Age:– Generally cancer increases with age– Most mortality 55-75 years– 10% of death in children <15y

• Heredity:– Inherited cancer syndromes– Familial cancer– Autosomal recessive syndromes of defective DNA

repair

• Carcinogens

Preneoplastic Disorders• Persistent regeneration:

– Ulcer, fistula: resulting in squamous cell carcinoma– Liver cirrhosis: resulting in hepatocellular carcinoma

• Hyperplasia and dysplasia:– Endometrial carcinoma– Adenoma of colon

• Metaplasia:– Barrett’s esophagus– Squamous metaplasia of bronchial epithelium

• Atrophy:– Chronic atrophic gastritis

• Inflammatory diseases– Ulcerative colitis

Screening for Cancer

• Breast cancer screening

• Cervical cancer screening

• Colon cancer screening

• Others: lung, prostate

Clinical Features

• Mass

• Local effect: function, structure

• Generalized (systemic) effect

• Complications

Clinical Features• Local effect:

– Location: small 1 cm pituitary adenoma is more serious than 10 cm leiomyoma of the uterus

– Eg. GI cancer: causes abdominal pain, intestinal obstruction, change in bowel habits.

– Lung cancer: causes cough, hemoptysis, chest pain

– Pancreatic cancer: causes obstructive jaundice.– Prostate cancer: causes urine obstruction.

Clinical Features• Local effect:

– Functional effect:– Pituitary adenoma may secrete: ACTH, TSH,

GH, LH, FSH– Adrenal cortical adenoma: steroid hormone,

aldosterone– Thyroid cancer: usually non functional

Clinical Features• Generalized effect:

– Cancer cachexia:• Loss of body mass (weight loss)

• Weakness, anorexia, anemia

• Mechanism:– Anorexia, taste change, CNS change, appetite change

– Increase in the basal metabolic rate by mediators eg. TNF, IL-1

– Paraneoplastic Syndormes• 10-15% of cancer

• Hypercalcemia due to PTH-related protein

• Cushing syndrome due to ACTH-like hormone

• Hypercoagulability and endocarditis

Clinical Features• Complications of tumors

– Ulceration– Bleeding– Infections– Infarction– obstruction

Diagnosis• Pathology

– Biopsy, excisional biopsy, incisional biopsy, core biopsy, tru-cut biopsy

– Ultasound-guided biopsy, CT-guided biopsy– FNA– Cytology– Excision, resection: local, wide excision

• Biochemical markers for tumors– Hormones, enzymes, and other markers– PSA (prostatic specific antigen): Prostate cancer– CEA (carcino embryonic antigen): colon cancer– Uses: detection, determine response, follow up

Diagnosis• Pathology

• Biochemical markers for tumors

• Molecular/Genetic studies:– Cytogenetics– PCR– FISH

Grading of Cancer

• Grading is estimation of tumor aggressiveness based on morphology– Nuclear grade (cytology)– Architectural grade

• Grades: different systems– 2 grades: low, high grade– 3 grades: well, moderately, poorly

differentiated– 4 grades: grade1, 2, 3, 4

Staging of Cancer

• Staging is determination of the extent of the spread of the tumor

• Include: tumor size, spread and metastasis• Different systems for staging• TNM staging: T: tumor, N: lymph node, M:

metastasis• AJC staging: American Joint Committee• Use: for planning of management, and

determining prognosis

Outcome of cancer

• Prognosis:– Usually estimated by 5-year survival– For statistical purposes– To plan management