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Tuesday, July 30, 2013

PPT On Types of Cancer

Presentation On Types of Cancer

Types of Cancer Presentation Transcript:

2.What is Cancer?
Cancer is a renegade system of growth that originates within the biosystem of a patient, more commonly known as the human body. There are many different types of cancers, but they all share one characteristic: unchecked growth that progresses toward limitless expansion.

Because cancer is so common, people have many questions about the biology, detection, diagnosis, possible causes and strategies for cancer prevention.

3.Different Types of Cancer
Cancer can originate almost anywhere in the body.

Carcinomas, The most common types of cancer, arise from the cells lining the and external surfaces internal the body. The cancers of lung of breast (Breast) and Colon are the cancers frequent.

The sarcomas are cancers that originate in cells that are in the supporting tissues of the body, such as bone, cartilage, fat, connective tissue and muscle.

Lymphomas are cancers that originate in the lymph nodes and tissues of the body's immune system.

Leukemias are cancers of immature blood cells that grow in the bone marrow and which have the tendency to accumulate in large quantities into the bloodstream blood.

4.Naming Cancers
Scientists use a variety of technical names to distinguish the many different types of carcinomas, sarcomas, lymphomas and leukemias. In general, these names are created using different Latin prefixes that correspond to the location where the cancer began its uncontrolled growth. For example, the prefix "osteo" means bone, a cancer that originates in the bone is called an osteosarcoma. Similarly, the prefix "adeno" means gland, which glandular cell cancer is called adenocarcinoma - for example, an adenocarcinoma of the breast.


6.Loss of Normal Growth Control
The cancer is caused by a loss of normal growth control. In normal tissues, the rates of new cell growth and old cell death are kept in balance. In the case of cancer, this balance is disrupted. This alteration may occur as a result of uncontrolled cell growth or the loss of a cell's ability to undergo cell suicide by a process known as "apoptosis". The apoptosis or "cell suicide" is the mechanism by which old or damaged cells normally self-destruct.

7.Example of Normal and Cancerous Growth
The outermost thin layer of normal skin known as the epidermis, has a thickness of about a dozen cells. The cells in the lower row of this layer, known as the basal layer, are divided accurately fast enough to replace cells that are constantly shed from the skin surface. Whenever one of these basal cells divide, produce two cells. One remains in the basal layer and retains the ability to divide. The other migrates outward from the basal layer and lose the ability to divide. The number of cells with the capacity to divide in the basal layer, therefore, remains the same.
 During the development of skin cancer, the normal balance between cell division and cell loss altered. Basal cells divide more rapidly now than it is necessary to replace cells that are shed from the surface of the skin. Whenever one of these basal cells divide, the two newly formed cells will often retain the ability to divide, which leads to an increase in the total number of cells with the capacity to divide.

8.The tumors (neoplasms) The Invasion and Metastasis
This gradual increase in the number of cells with the capacity to split creates a growing tissue mass known as a "tumor" or "neoplasm". If the rate of cell division is relatively quick and there are no signs of "suicide" in place to trigger cell death, the tumor will grow rapidly in size, if cells divide more slowly, tumor growth will be slower. Regardless of the rate of growth, tumors eventually become enlarged because new cells are being produced in larger amounts than necessary. As more and more of these cells with the capacity to accumulate divide the normal tissue organization gradually altered.
Cancers are able to spread throughout the body through two mechanisms: invasion and metastasis. Relates to the invasion and penetration direct migration of cancer cells in the surrounding tissues. Metastasis refers to the ability of cancer cells to penetrate into lymphatic and blood vessels, circulate through the bloodstream, and then invade normal tissues elsewhere in the body. 

9.The malignant and benign tumors and dangerousness 
Depending on whether they can spread or not by invasion and metastasis, tumors are classified as benign or malignant. Benign tumors are tumors that can not be spread by invasion or metastasis, and therefore, they only grow locally. Malignant tumors are tumors that are capable of spreading by invasion and metastasis. By definition, the term "cancer" applies only to malignant tumors
A malignant tumor, a "cancer" is a more serious health problem that a benign tumor because cancer cells can spread to distant parts of the body. For example, a melanoma (a cancer of pigmented cells) that originates in the skin may have cells that enter the bloodstream and spread to distant organs, such as liver or brain. Cancer cells in the liver is called metastatic melanoma, not liver cancer. Metastases share the name of the original tumor ("primary"). Melanoma cells growing in the brain or liver can alter the functions of these vital organs and thus jeopardize potentially life

10.Hyperplasia and Dysplasia
Instead of detecting a benign or malignant tumor, microscopic examination of the biopsy specimen detects a condition sometimes called "hyperplasia". Hyperplasia refers to the increase in size of a tissue occurs by excessive cell division rate, which leads to a larger number of cells than normal. However, the cell structure and the orderly arrangement of the cells within the tissue remain normal and hyperplastic process is potentially reversible. Hyperplasia may be a normal reaction to an irritating stimulus tissue. An example of hyperplasia is a callus that has formed in your hand when you first learn to use a tennis racket or a golf club.
 In addition to hyperplasia, microscopic examination of the biopsy specimen can detect other noncancerous condition called "dysplasia". Dysplasia is an abnormal type of excessive cell proliferation characterized by loss of normal tissue arrangement and cell structure. These cells often return to normal, but sometimes gradually become malignant. The areas of dysplasia should be monitored closely by a medical professional because of its potential to become malignant. Sometimes they need treatment.

11.Carcinoma In Situ
The most severe cases of dysplasia are sometimes referred to as "carcinoma in situ". In Latin, the term "in situ" means "in place", so carcinoma on-site refers to an uncontrolled growth of cells that remains on its original site. However, carcinoma on-site can become invasive, metastatic malignancy and, therefore, are generally surgically removed if possible.

12.The Classification and Staging of Tumor
Microscopic examination also provides information about the likely behavior of the tumor and its response to treatment. Cancers with more abnormal appearing cells and numerous cells with the capacity to divide, they tend to grow more quickly, spread to other organs more frequently and be less responsive to therapy than cancers whose cells have a more normal appearance. Based on these differences in microscopic appearance, medical assign a numerical "grade" the majority of cancers. In this classification system, a low grade (grade I or II) refers to cancers with fewer cell abnormalities unlike those with higher numbers (grade III or IV). After cancer is diagnosed, doctors formulated the following three questions to determine how the disease: How large the tumor is and how far it has invaded surrounding tissues?
Do cancer cells have spread to regional lymph nodes?
Is it has spread (metastasized) cancer to other parts of the body?
Based on the answers to these questions, the cancer is assigned a "stage". The probability of survival for the patient is best when the cancer is detected at an earlier stage.

13.Cancer Detection and Diagnosis

14.Cancer Detection and Diagnosis
The detect cancer in its early stage can affect the outcome of the disease of certain cancers. When cancer is found, the doctor will determine what kind it is and how fast it is growing. He or she will also determine if cancer cells have invaded nearby healthy tissue or have spread (metastasized) to other parts of the body. In some cases, early detection of cancer can reduce the risk of a person dying because of cancer. For this reason, the highest priority currently cancer researchers is to improve methods for early detection
Some people visit the doctor only when they feel pain or when they notice changes such as a lump or nodule in the breast or bleeding or unusual discharge. But do not wait until then to be examined (a) because the early stage cancer may not have any symptoms. That is the reason why screening for some cancers are important, particularly as you get older. The detection methods are designed to detect cancer in people without symptoms

15.Review of Cervical Cancer Screening
A detection technique known as the Pap test allows for early detection of cervical cancer (cancer of the cervix or uterus), the narrow portion of the uterus that extends downward into the upper vagina. In this procedure, a doctor uses a small brush or wooden scraper to remove a sample of cells from the cervix and upper vagina. The cells are placed on a slide and sent to a laboratory where it uses a microscope for abnormalities. Since the 1930s, early detection through the use of the Pap test has helped reduce the rate of death from cervical cancer (cancer of the cervix or uterus) in more than 75 percent.

May be required if additional evidence come to find abnormalities. Currently there are 13 high-risk types of human papillomavirus (HPV, by its initials in English) recognized as the leading cause of cervical cancer. The Food and Drug Administration of the USA. has approved an HPV test that can identify its presence in a tissue sample. This test can detect the virus even before there are any conclusive visible changes in cervical cells.

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