CANCER IN ENGLISH

                                                    

                                                CANCER IN ENGLISH

                          watch my YouTube video to understand this topic in easy way-

         https://www.youtube.com/watch?v=j6jyv8LnJFg

CANCER

•        Cancer is a condition in which some of the body’s cells grow uncontrollably (uncontrolled multiplication of cells) and spread to other parts of the body. 

•        Most cancers occur in people older than 65 years of age and the incidence of cancer is higher in men than in women. Cancer can start almost anywhere in the human body, which is made up of trillions of cells.

•        CANCER SYMBOL

•        Cancer ribbons are loops of ribbon that people wear to show their support for those with cancer or to spread awareness about the disease. There are 43 different colors. eg, pink for breast cancer and orange for leukemia.

•        PATHOPHYSIOLOGY OF CANCER

•        The disease process in cancer begins when an abnormal cell which is transformed by the genetic mutation of the cellular DNA. This abnormal cell forms a clone and begins to proliferate abnormally. These cells are knon as malignant cells or cancer cells.

•        CHARACTERISTICS OF CANCER CELLS

•        cancer cells share some common cellular characteristics related to the cell membrane, special proteins, the nuclei, chromosomal abnormalities, and the rate of mitosis and growth.  

•        The cell membranes are altered in cancer cells, which affect fluid movement in and out of the cell. The cell membrane of malignant cells also contains proteins called tumor-specific antigens.    

•        For example, carcinoembryonic antigen [CEA] and prostate-specific antigen [PSA]), which develop over time as the cells become less differentiated (mature). These proteins distinguish malignant cells from benign cells of the same tissue type.

•        Malignant cellular membranes also contain less fibronectin, a cellular cement. They are therefore less cohesive and do not adhere to adjacent cells readily that’s why they metastasize easily

•        nuclei of cancer cells are large and irregularly shaped .

•        Nucleoli are larger and more numerous in malignant cells .

•        Chromosomal abnormalities and fragility of chromosomes are commonly found 

•        Cell division occurs more frequently in malignant cells than in normal cells. As the cells grow and divide, more glucose and oxygen are needed. If glucose and oxygen are unavailable, cancer cells use anaerobic metabolism  to produce energy and continue to grow rapidly.

•        INVASION AND METASTASIS

•        Cancer have the ability to spread by invasion and metastasis.

•        Invasion, which refers to the growth of the primary tumor into the surrounding host tissues. Malignant cells are less adherent and may break off from the primary tumor and invade adjacent structures.

•        Metastasis is the dissemination or spread of malignant cells from the primary tumor to distant sites (another organ) by direct spread of tumor cells to body cavities or through lymphatic and blood circulation.

•        CAUSATIVE FACTORS

•        Cancer is a multifactorial disease. Factors responsible for cancer include-

•         Viruses and bacteria 

•         Physical agents,

•         Chemical agents, 

•          Genetic or

•           familial factors,

•         Dietary factors, and

•         Hormonal agents.

•        VIRUS AND BACTERIAS- Viruses are thought to incorporate themselves in the genetic structure of cells leading to cancer. For example, the Epstein-Barr virus is highly suspect as a cause in Burkitt lymphoma, nasopharyngeal cancers, and some types of non-Hodgkin and Hodgkin lymphoma.

•        Some bacteria may also cause cancer. Helicobacter pylori (H. pylori) was the first bacterium to be termed a definite cause of cancer in humans. H. pylori has been associated with an increased incidence of gastric malignancy related to chronic superficial gastritis.

•        PHYSICAL FACTORS- Physical factors associated with carcinogenesis include exposure to

•         sunlight or radiation,

•        chronic irritation or inflammation, and

•        tobacco use.

•        Excessive exposure to the ultraviolet rays of the sun, Exposure to ionizing radiation can occur with repeated diagnostic x-ray procedures and exposure to radioactive materials at nuclear weapon manufacturing sites or

•        nuclear power plants are associated with a higher incidence of leukemias, multiple myeloma, and cancers of the lung, bone, breast, thyroid, and other tissues

•        CHEMICAL FACTORS- Exposure to hazardous chemicals produce their toxic effects by altering DNA structure in body sites distant from chemical exposure. The liver, lungs, and kidneys are the organ systems most often affected

•        Tobacco, including more than 60 chemicals that are known carcinogens. Tobacco may also act with other chemical substances, such as alcohol, asbestos and  uranium to promote cancer development.

•        There is extensive list of suspected chemical substances and continues to grow and includes aromatic amines and aniline dyes; pesticides and formaldehydes; arsenic, soot, and tars;

•        asbestos; benzene; betel nut and lime; cadmium; chromium compounds; nickel and zinc ores; wood dust; beryllium compounds; and polyvinyl chloride.

•        GENETICS AND FAMILY FACTORS-  Genetic factors also play a role in cancer cell development. Specific cancers with underlying genetic abnormalities include Burkitt lymphoma, chronic myelogenous leukemia, meningiomas, acute leukemias, retinoblastomas, Wilms tumor, and skin cancers, including malignant melanoma.

•        DIETARY FACTORS-  Dietary factors to increase the risk of cancer include fats, alcohol, salt-cured or smoked meats, nitrate- containing foods, and red and processed meats. Alcohol increases the risk of cancers of the mouth, pharynx, larynx, esophagus, liver, colorectum,  and breast.

•        HORMONAL FACTORS- Cancers of the breast, prostate, and uterus are thought to depend on endogenous hormonal levels for growth. Diethylstilbestrol (DES) has long been recognized as a cause of vaginal carcinomas.    

•        Oral contraceptives and prolonged estrogen therapy are associated with an increased incidence of hepatocellular, endometrial, and breast cancers. Hormonal changes related to the female reproductive cycle are also associated with cancer incidence.

•        Early onset of menses (under age 12) and delayed onset of menopause (after age 55), nulliparity (never giving birth), and delayed childbirth (after age 30) are all associated with an increased risk of breast cancer.

•        INVESTIGATION AND MANAGEMENT- Diagnostic investigations and management of cancers will be discussed during upcoming lectures under specific cancer topics like breast cancer, skin cancer, blood cancer etc.