What is Cancer?
- Cancer is a disease characterized by the uncontrolled and abnormal growth of cells.
- In cancer, the body loses its contact inhibition property.
- Undifferentiated, it invites and destroys surrounding healthy tissues.
- Cancer can occur in different parts of the body and can spread to other areas through the bloodstream or lymphatic system.
- The causes of cancer are complex and can include genetic factors, environmental factors, and lifestyle choices.
- Cancer is a harmful disease. Nearly 609,360 people die of cancer each year in the USA and worldwide. According to the data, nearly 10 million deaths will take place in 2020.
- There are various types of cancer, each with its own causes, risk factors, symptoms, and treatment options. Let us know more about cancer.
What is a tumor?
A tumor is an abnormal mass of tissue that is often the result of uncontrolled cell growth. Umors can be either benign or malignant.
What are the types of tumors?
- Benign tumor
- Malignant tumor
- Benign tumor: A benign tumor (non-malignant tumor) is a non-cancerous tumor that does not transfer to other parts of the body. A benign tumor grows slowly and has a distinct border. It causes only limited damage.
- Malignant tumor: Malignant tumors are cancerous in nature. They grow rapidly and spread to distant sites via the bloodstream or the lymphatic system. This spread is called metastatic. It is very dangerous and can cause death.
What is metastatic?
The property of cancerous cells is to transfer from one part of the body to another via body fluid and create new tumors.
Causes of cancer
Cancer is a complex disease with many contributing factors. Some of the common causes of cancer include:
- Physics
- Chemical
- Genetic
- Physical
- Lifestyle
- Hormone
- Infection and inflammation
- Virus
- Bacteria
- Genetic factors
- Parasite
- Radiation
- Environmental
- Non-iionizing radiation
- Viral infections
- Age
- Immune system dysfunction
- Physical agents: Physical agents of cancer: alcohol consumption, tobacco use, betel nut smoking, an unhealthy diet, air pollution, and Kangri-Kashmiri. All these factors are the cause of physical cancer.
- Neoplastic transformation: Normal cells convert to cancerous cells Neoplastic transformation refers to the process by which normal cells acquire genetic mutations that enable them to grow and divide uncontrollably, leading to the formation of a tumor. This transformation can result in the development of cancer. Neoplastic transformation is often accompanied by the ability of these cells to invade surrounding tissues and spread to other parts of the body, a process known as metastasis.
- Chemical agents: Chemical agents are chemicals that are known to be carcinogenic or linked to cancer development. For example, constant use of artificial sweeteners, tobacco smoke (which contains many carcinogenic chemicals), arsenic, asbestos, benzene, vinyl chloride, formaldehyde, nitrosamines, aflatoxins, radon, polycyclic aromatic hydrocarbons (PAHs), and certain pesticides, as well as dye work, alcohol, an excess fat diet, red meat, beef, the bowel, hormonal influence on the breast, etc. All such agents cause cancer.
- Radiation: Certain types of radiation can increase the risk of developing cancer. Such as X-rays, gamma rays, cosmic rays, alpha particles, beta particles, UV rays, nuclear booms, neutrons, etc.) can damage DNA and cause cancer.
- Biological agents: Cancer can be caused by a variety of biological agents, including genetic mutations, bacteria, hormones, environmental carcinogens, parasites, schistosomiasis, hepatitis B, and hepatitis C viruses. human papilloma virus family: the T-cell lympotropic virus type 1 (HTLV-1) and two herpes viruses, the Epstein-Barr virus (EBV) and the Kaposi sarcoma-associated herpes virus (KSHV).
- Ogcogenic virus: An oncogenic virus is a virus that can cause cancer in infected hosts. Like the ras gene family (rasH, rasK, and rasN), human papillomavirus (HPV), Epstein-Barr virus (EBV), and hepatitis B and C viruses. These viruses are able to manipulate the host's cell cycle, promote cell division, and inhibit cell death, leading to the uncontrolled proliferation of cells, which can eventually develop into cancerous tumors.
- Cellular or proto-oncogenes: found in normal cells, become cancerous when they are mutated. Ex-HHER2 gene.
Types of cancer
There are many different types of cancer. Some common types include:
- Carcinoma: Carcinoma is a type of cancer that is derived from epithelial tissue. 80% of all tumors worldwide are carcinomas. Ex: esophagus, skin, breast, kidney, liver, lungs, pancreas, prostate gland, colon, cervix, stomach, The term "carcinoma" is often used to describe many types of cancer that arise from epithelial cells. Treatment for carcinoma typically involves a combination of surgery, radiation therapy, chemotherapy, or targeted therapy, depending on the location and stage of the cancer. Early detection and treatment are essential for a better prognosis.
- Melanoma: Melanoma is the most serious type of skin cancer and develops in the cells (melanocytes) that produce malian, the pigment that gives your skin color. It is often linked to ultraviolet (UV) radiation from the sun or tanning beds as a major risk factor. Melanoma can occur anywhere on the skin, but it is most commonly found on the back in men and on the legs in women.
- Sarcoma: Sarcoma is a type of cancer that derives from connective tissue and muscular tissue in the mesoderm. Sarcoma tumors generally develop in the bone and soft tissue muscules, tendon, cartilage, nerves, fat, and blood vessels of your arms and legs, more specifically (osteoma), cartilage, tendon, and adipose.
- Leukemia: leukemia, also called blood cancer, usually involves the white blood cells (WBC), which are characterized by abnormally growing WBC cells. Symptoms may include fatigue, weight loss, frequent infections, and easy bruising. Treatment options include chemotherapy, radiation therapy, targeted therapy, and stem cell transplants. Early detection and treatment are crucial for managing leukemia effectively.
- Lymphoma: Lymphoma is a type of cancer that originates in the lymphatic system, which is a part of the body's immune system. There are two main types of lymphoma: Hodgkin lymphoma and non-Hodgkin lymphoma. Both types of lymphoma affect the lymphocytes; in this cancer, cells fight each other in the immune system.
Treatment of cancer
Various types of treatments are available, like surgery, chemotherapy, hormone therapy, immunotherapy, hyperthermia, radiation therapy, photodynamic therapy, stem cell transplant, targeted therapy, and stem cell or bone marrow transplant.
- Surgery: In surgery, a surgeon removes affected parts of the patient’s body.
- Hormone therapy: the use of hormones to treat cancer. EX: prostate and breast cancer The most common drugs used in hormone therapy are Tamoxifen, Toremifene (Faston), and Fulvestrant (Faslodex).
- In breast cancer, hormone therapy may involve blocking the action of estrogen or progesterone, as these hormones can stimulate the growth of some types of breast cancer cells. This can be achieved through medications like selective estrogen receptor modulators (SERMs), aromatase inhibitors, or estrogen receptor downregulators.
- In prostate cancer, hormone therapy aims to reduce the levels of androgens (male hormones), such as testosterone, which can promote the growth of prostate cancer cells. This can be done through medications that either block the production of androgens or inhibit their action on prostate cancer cells.
- Hormone therapy may be used alone or in combination with other treatments like surgery,chemotherapy, or radiation therapy, depending on the type and stage of cancer. It is often used as a long-term treatment for certain types of cancer to help manage the disease and prevent its recurrence.
- Radiation therapy: In radiation therapy, beams of intense energy are used to kill cancerous cells. E.g., X-rays destroy rapid-growing cells.
- Radiation therapy: Radiation therapy, also known as radiotherapy, is a common treatment method used by cancer patients. It utilizes high-energy radiation beams to target and destroy cancer cells or shrink tumors. Radiation therapy can be delivered externally using a machine that directs radiation beams towards the affected area (external beam radiation) or internally by placing radioactive materials near the cancer site (brachytherapy).
- Radiation therapy works by damaging the DNA within cancer cells, preventing them from dividing and growing. While normal cells can also be affected by radiation, they can usually repair themselves better than cancer cells. The goal of radiation therapy is to destroy cancer cells while minimizing damage to surrounding healthy tissues.
- Radiation therapy is planned and delivered by a team of radiation oncologists, radiation therapists, medical physicists, and other healthcare professionals. Treatment planning is tailored to each individual patient based on factors such as the type and stage of cancer, the location of the tumor, the size of the tumor, and the patient's overall health. The side effects of radiation therapy may vary depending on the area being treated and can include fatigue, skin changes, nausea, and hair loss.
- Chemotherapy: In chemotherapy, drugs are used to kill cancerous cells. The most common anti-cancer drugs used are methotrexate, vinblastine, busulfan, bendamustine, vinblastine, gemcitabine, paclitaxel, gemcitabine, and cisplatin. Side effects of chemotherapy The most common side effects are: hair fall, anemia, feeling sick all the time, sore mouth, loss of appetite, fatigue, etc.
- Immunotherapy: Your body's immune system is used to find and destroy cancerous cells. E.g., monoclonal antibodies, cancer vaccines, adoptive cell therapy, T-cell transfer therapy, CAR-T cell therapy, checkpoint inhibitors, and cytokines.
How to diagnose cancer
A diagnosis of early-stage cancer can be treatable.
- Biopsy: During a biopsy, a surgeon cuts a small portion of the affected part, collects a sample of tissue, and tests it in a laboratory under a microscope.
- The PAP test (Papanicolaou test): The PAP test, or Pap smear, is a screening test commonly used to detect cervical cancer in women. It involves collecting cells from the cervix to check for any abnormalities that may indicate the presence of pre-cancerous or cancerous cells. Regular Pap tests are essential for the early detection and treatment of cervical cancer. It is usually recommended that women start getting Pap tests around the age of 21 and continue to have them regularly as advised by their healthcare provider.
- Radiology: Cancer is diagnosed using machines like X-rays, computed tomography (CT scan), magnetic resonance imaging (MRI), and positron emission tomography (PET).