G I TRACK: CANCER

Sumit Mohite 11

Vishal Mangukiya 12

Jitendra Mourya 13

Prasad Bhandlikar 14

Sanjeev Kumar 15

Cancer: General Etiology and Pathogenesis

What is cancer?

Abnormal cell growth (neoplasia)

Malignant as opposed to benign

Benign: slow growth, non-invasive, no metastasis

Malignant: rapid growth, invasive, potential for metastasis

What causes the mutations that lead to

cancer?

Viruses: HPV --> cervical cancer

Bacteria: H. pylori --> gastric cancer

Chemicals --> B[a]P --> lung cancer

UV and ionizing radiation --> skin cancer

What do these agents have in common?

Mutagens

Viruses: insertional mutagenesis

Chemicals: DNA adducts

UV and ionizing radiation: single

and double strand DNA breaks

What types of genes get mutated in

cancer?

Oncogenes are activated

Normal function: cell growth, gene transcription

Tumor suppressor genes are inactivated

Normal function: DNA repair, cell cycle control, cell death

Phenotype of a cancer cell

The Six Hallmarks of Cancer

Self-sufficient growth signals Constitutively activated growth factor signalling

Resistance to anti-growth signals Inactivated cell cycle checkpoint

Immortality Inactivated cell death pathway

Phenotype of a cancer cell (cont'd)

The Six Hallmarks of Cancer

Resistance to cell death Activated anti- cell death signalling

Sustained angiogenesis Activated VEGF signalling

Invasion and metastasis Loss of cell-to-cell interactions, etc.

p53—a classic tumor suppressor

“The guardian of the genome”

Senses genomic damage

Halts the cell cycle and initiates DNA repair

If the DNA is irreparable, p53 will initiate the cell

death process

Esophageal cancer :-

Esophageal cancer usually develops in the inner layer cells

and grows outward.

Treatment :-

Endoscopic treatments such

as photodynamic therapy

Radiofrequency ablation

Sign & Symptoms :-

chronic irritation and inflammation

resulting from a backwash of acidic

stomach.

Painful or difficult swallowing.

Weight loss.

Pain behind the breastbone.

Hoarseness and cough.

Indigestion and heartburn.

Stomach Cancer

What is Stomach Cancer? Stomach Cancer (Gastric cancer)-malignant tumor arising

from the lining of the stomach.

Stomach cancers are classified according to the type of tissue

where they originate.

Most common type of stomach cancer-

Adenocarcinoma(Starts in the glandular tissue of the

stomach)

Accounts-90% to 95% of all stomach cancers.

Other forms of stomach cancer-lymphomas, which involve

the lymphatic system, and sarcomas, which involve the

connective tissue (such as muscle, fat, or blood vessels).

Who Does it Effect?Males over the age of 55.

A diet low in fruits and vegetables.

A diet high in salted, smoked, or preserved foods.

Chronic gastritis.

Pernicious anemia.

Family history of gastric cancer.

Smokers

People who use tobacco or drink alcoholic beverages regularly.

Workers in certain industries-the coal mining, nickel refining, and rubber and timber processing industries.

Causes Gender - men have more than double the risk of getting stomach

cancer than women.

Genetics - genetic abnormalities and some inherited cancer syndromes may increase your risk.

Advanced age -stomach cancer occurs more often around ages 70 and 74 in men and women, respectively.

Family history of gastric cancer can double or triple the risk of stomach cancer.

Lifestyle factors such as smoking, drinking alcohol, and eating a diet low in fruits and vegetables or high in salted, smoked, or nitrate-preserved foods may increase your risk

Helicobacter pylori (H. pylori) infection of the stomach. H. pylori is a bacterium that infects the lining of the stomach and causes chronic inflammation and ulcers.

Signs and Symptoms In the early stages of stomach cancer,

Indigestion and stomach discomfort

A bloated feeling after eating

Mild nausea

Loss of appetite

Heartburn

Cont… In more advanced cancer,

Discomfort in the upper or middle part of the abdomen.

Blood in the stool (which appears as black, tarry stools).

Vomiting or vomiting blood.

Weight loss.

Pain or bloating in the stomach after eating.

Weakness or fatigue associated with mild anemia (a deficiency in red blood cells).

Stomach Cancer Diagnosis

By physical examination-enlarged lymph nodes, an enlarged

liver, increased fluid in the abdomen (ascites), or abdominal

lumps felt during a rectal exam.

Test such as

Upper GI series

Gastroscopy and biopsy

CT scans, PET scans, bone scans, laparoscopy and

endoscopic ultrasound.( to check if cancer is spread)

How Is Stomach Cancer Treated?

Stomach cancer may be treated with the following, in

combination, or alone:

Surgery, called gastrectomy, to remove all or part of

the stomach, as well as some of the tissue surrounding

the stomach.

Chemotherapy.

Radiation therapy.

Prognosis/ Survival Rate

Prognosis depends on the stage of the disease.

Stomach cancer metastasizes in as many as 80% of

cases, resulting in a very poor prognosis.

In Japan, where stomach cancer often is diagnosed

early, the 5-year survival rate is about 50%.

In the United States and most of the Western world, the

5-year survival rate ranges from 5–15%.

Management

Follow-up care is necessary for stomach cancer

patients.

Regular physical examination and tests (e.g., CT scan,

MRI scan) are used to detect recurrent or advanced

disease.

In addition, patient’s dietary intake must be monitored

regularly to promote health.

Liver cancer :-

•Starts somewhere else and spreads to the liver.

•Reason viral hepatitis

4 main types :-

1) Angiosarcoma,

A rare type of cancer that starts in the blood vessels of the liver.

2) Hepatoblastoma,

Another rare type of liver cancer occurring chiefly in young

children.

3) Cholangiocarcinoma,

Which starts in the bile ducts

4) Hepatocellular carcinoma,

Also known as Hepatoma.

The most common liver cancer is hepatocellular carcinoma

which accounts for

approximately 84% of liver cancers.

As is the case with stomach cancer, liver cancer is hard to

diagnose.

Treatment :-

•Chemotherapy

•Radiofrequency Ablation

•Gene Therapy

•Magnetic-Chemotherapy

Colorectal cancers :-

• Colorectal cancers are common, and occur more frequently in

people over the age of 50.

• Colorectal cancers are highly treatable when detected early,

but the symptoms are often not obvious in early stages.

Sign & Symptoms :-

•Blood (either bright red or very dark) in the stool.

•Diarrhea & constipation.

•Stools that are narrower than usual.

•Frequent gas pains, bloating, fullness, or cramps.

•Weight loss for no known reason.

•Feeling very tired.

•Vomiting.

Treatment :-

•Surgery (most often a colectomy) to remove cancer cells

•Chemotherapy to kill cancer cells

Chemotherapy drugs are :-

capecitabine, fluorouracil, irinotecan, leucovorin, oxaliplatin

•Radiation therapy to destroy cancerous tissue

Management of Cancer

Keep to a normal weight

Avoid alcohol

Take regular exercise

Avoid smoking

Add Garlic to everything you Eat

Eat plenty of Fruits and Vegetables

Limit Fats and oily food

Avoid unnecessary Scans