Also called malignancy, is represented by an abnormal growth and division of cells that interfere with the body´s normal functioning. This abnormal growth can occur in any part of the body and lead to the development of tumors (due to the fact that cells multiply out of control, new ones are made when they’re not needed and the older ones cease to undergo cellular death). Tumors can be benign (that don’t spread to other parts of the body) or malignant (that grow out of control and can invade other tissues – process called metastasis). There are more than 100 types of cancer, but among the most frequent are: breast cancer, lung cancer, prostate cancer, colon cancer, skin cancer and lymphoma (cancer of the immune cells – lymphocytes). When a certain type of cancer metastasizes, the cells from the initially affected part of the body travel to another part and start growing there, but they are still specific to the initial part of the body and the cancer does not change its name (e.g. if lung cancer metastasizes and affects the bones, it is still called lung cancer (that has spread), because the cells where it initially started are lung cells).

 

Types of cancer:

 

Carcinomas – most common type, starts in the epithelial cells (the cells that cover inside and outside surfaces of the body:

 

Adenocarcinoma – forms in the epithelial cells that produce fluids or mucus (most of the breast, colon and prostate cancers)

 

Basal cell carcinoma – cancer that begins in the lowest layer of the epidermis (the outer layer of skin)

 

Squamous cell carcinoma (epidermoid carcinomas) – cancer that forms in the squamous cells (epithelial cells beneath the outer layer of the skin); cell that form the lining of different organs: stomach, lungs, bladder, kidneys, intestines

 

Transitional cell carcinoma – cancer of the transitional epithelium or urothelium; this epithelium is found in the lining of the ureters, parts of the kidneys, bladder

 

Sarcoma – cancers of the bone and soft tissues (muscle, fat, blood vessels, lymph vessels, tendons, ligaments)

 

Leukemia – cancers that start in the blood-forming tissue of the bone marrow; these cancers do not form solid tumors.

Types of leukemia are based on the rate of the disease’s evolution (acute or chronic) and on the type of blood cells in which the cancer started.

 

Lymphoma – cancer of the white blood cells (part of the immune system)

Two main types:

Hodgkin lymphoma – abnormal lymphocytes that develop from B cells (type of white blood cells)

Non-Hodgkin lymphoma – large group of cancers that begin in the lymphocytes; form in the B cells or T cells

 

Multiple myeloma – cancer that begins in plasma cells (cells of the immune system) and leads to the formation of tumors in the bones throughout the body

 

Melanoma – cancer of the cells that make melanin (pigment): skin cancers and intraocular melanoma

 

Brain and spinal cord tumors

 

Stages of cancer:

Stage 0 – the cancer is still located at the site where it initially occurred and has not spread to surrounding tissues

Stage I – early stage cancer that has not spread to the lymph nodes or other parts of the body

Stage II and III – stages that indicate larger tumors that have grown into surrounding tissue and spread to lymph nodes but not to other parts of the body

Stage IV – advanced or metastatic cancer – spread to other organs or parts of the body

Causes

Cancer is caused by changes in the genes that control cell function (giving them signals to grow out of control, divide and “forget” to die)

 

Only a small percent (5-10%) are inherited, while the rest of the mutations occur during a person’s lifetime probably due to infections, diseases or environmental factors that can affect the genes

 

Risk factors:

 

Carcinogenic substances: arsenic, benzene, cadmium, coal tar, formaldehyde, emissions from coal combustion, nickel compounds, radon, soot, thorium, etc

Tobacco smoke

Radiation (ionizing radiation: x-rays, gamma rays, etc)

Sunlight (UV radiation)

Infectious agents (viruses, bacteria, parasites)

Chronic inflammation

Diet

Age

Immunosuppression

Hormone therapy (increases cancer risk in menopausal women)

Obesity (increase the risk of colon, rectum, endometrium, kidney, pancreas and gallbladder cancer)

Alcohol (increases the risk of mouth, throat, esophagus, larynx, liver and breast cancer)

Lack of physical activity

Air pollution

Symptoms and signs

An unusual lump on the body

Abnormal bleeding or discharge

A persistent cough

Unintended weight loss

Difficulties regarding bowel movements

Difficulties swallowing

Digestive system problems

Unexplained pain

Unexplained fatigue

Skin changes, changes in a mole on the skin

Persistent sores or ulcers

Unexplained abdominal discomfort

Jaundice (yellow coloring of the skin)

Unexplained fever

Advice

Diagnostic tests and procedures:

 

Tumor marker tests (biomarkers): increased levels of tumor markers in the blood, urine or body tissue can indicate cancer

 

Ultrasounds and imaging tests such as MRIs (magnetic resonance imaging), PET scans (positron emission tomography), CT scans (computerized tomography) – that offer detailed images of the internal organs and tissues

 

Bone scans

 

Bone marrow aspiration and biopsy

 

Biopsies of the suspected cancerous tissues

 

Colonoscopy – examination of the large intestine

 

Endoscopy – procedure that consists in examining the inside of the body through an endoscope

 

Digital rectal examination – screening test to check the prostate, lower colon

 

Electrocardiograms and echocardiograms – to check heart function and detect possible problems

 

Mammography – type of x-ray that can detect tumors/abnormalities in the breasts

 

Pap test/Pap smear – for cervical cancer detection

 

 

Treatment options:

Treatment options are based on the cancer’s type, stage, prognosis, possible side-effects, overall health and patient’s preference.

 

Surgery – the removal of the cancerous tissue and surrounding tissues (depending on how advanced the cancer is)

 

Chemotherapy – drugs are used to destroy cancer cells; it can be used before – to reduce the size of a large tumor and make it more easily operable – or after surgery; common side-effects may include: nausea, vomiting, fatigue, muscle pain, headaches, stomach pain, diarrhea, constipation, blood disorders, loss of appetite, hair loss

 

Radiation therapy: external beam radiation (intense energy beams are used to destroy cancer cells while avoiding healthy tissue) and brachytherapy (radioactive material is places inside the body and gives off low-dose radiation over a period of time)

 

Immunotherapy (biotherapy) – type of cancer treatment that implies using the body’s own immune system to fight cancer: the immune cells are genetically engineered (in some cases even to carry drugs or radiation directly to the cancer cells) and put back into the patient’s body, non-specific immunotherapies (interferons and interleukins), cancer vaccines (prevention vaccine such as Gardasil and Cervarix for cervical cancer, and treatment vaccines such as sipuleucel-T: Provenge)

 

Stem cell transplant – often recommended in treating leukemia, multiple myeloma, some types of lymphoma

 

Personalized and targeted therapy – therapies (oral or intravenous medication) that target the cancer’s specific genes, proteins, receptors; e.g. HER2 (human epidermal growth factor receptor) inhibitors in breast cancer, EGFR (epidermal growth factor receptor) blocker in colorectal cancer, BRAF gene inhibitors in melanoma

MISCONCEPTIONS
  • A cancer diagnosis is a death sentence

     

    Consuming sugar can provoke or worsen cancer

     

    Some types of cancer can be contagious

     

    If cancer is exposed to air during surgery, it will spread

     

    If a family member has cancer, you will most likely develop cancer too

     

    Antiperspirants and hair dyes can cause cancer

     

    Any lump on the body is cancerous

     

    Cancer is actually a fungal infection

     

    Cancer treatments do more harm than good

     

    Sharks don’t develop cancer

     

    To undergo cancer treatment you have to be hospitalized

     

    The medical world has made no progress regarding cancer treatment in the last 20 years

Statistics

Around 25% of all the new cancer cases diagnosed are in the age group 65-74 years old

 

The average age of cancer diagnosis: 66 years

 

Median age of diagnosis for: breast cancer – 61, colorectal cancer – 68, lung cancer – 70, prostate cancer – 66

 

Estimated cancer deaths in the US in 2014: 310,010 men and 275,710 women (the leading cause being lung and bronchus cancers)

 

Cancer death rates are higher among men than among women in every racial and ethnic group:

3/100,000 men and 153.6/100,000 women (Non-Hispanic white)

6/100,000 men and 171.2/100,000 women (African American)

4/100,000 men and 92.1/100,000 women (Asian/Pacific)

191/100,000 men and 139/100,000 women (American Indian)

2/100,000 men and 101.3/100,000 women (Hispanic)

 

The highest cancer mortality is recorded among black men and women

 

Estimated new cancer cases in 2016: 1,685,210 (US)

 

Worldwide, the annual number of cancer cases is expected to rise over the next two decades, from 14 million (2012) to 22 million