Reseach Paper

Cancer

Cancer is an abnormal growth of cells. These cancer cells reproduce nonstop no matter the space available, nutrients needed or hormones sent to the cells to stop bone growth. Cancer cells differ from regular cells in shape, they can spread to other parts of the body and they never function properly. These cells grow into tumors which divide uncontrollably and spread into other parts of the body like the cancer cells themselves. There are two types of cancers benign and malignant. Benign tumors grow very slowly and do not spread to other parts of the body. Malignant tumors grow rapidly destroy and spread to other tissue quickly. Malignant tumors are classified by two ways, "locally invasive" and "metastatic". A locally invasive cancer sends out strings of cancer into other healthy tissue. Metastatic cancer would send cells into other parts of the body and the cells traveling through the body would anchor themselves in another part of the body developing into a tumor.

There are many forms of cancer and along the many forms of cancer are different risk factors. As humans develop in age they are more prone for cancer thats why different tests for different types of cancer are encouraged as people become elderly. Tobacco and alcohol usage also is a risk factor for certain mouth cancers. Also if one does not eat the proper fruits and vegetables there cannot be proper tooth growth which leads to teeth using cancerous ways to grow. Having a certain diseases can also lead to lead someone to develop a cancer. For example having the hepatitis B or C virus can lead to liver cancer. Also human papilloma virus, an STD and a virus that affect women, can lead to cervical cancer. Various skin cancers are caused by excess exposure to ultra-violet radiation. Along with light skin color can increase your chances of getting melanoma (a skin cancer). Also genes play a large part in your risk of getting cancer. For example if you have the genes BRCA-1 or BRCA-2 it plays a large role in a person's ability to acquire breast cancer. Genes control how your body works and if there are genes that would cause your cells to behave abnormally, thus then cancer can be a posiibility.

As stated abovethere are various forms of cancer. One of the forms of cancer that affect many children is Osteosarcoma. Osteosarcoma is a malignant cancer of the bone that develop in the osteoblast cells that form the outer shell of bones. It occurs most often in children, adolescents, and young adults. It occurs most often in younger people because at these ages a grow spurt occurs in humans. The cells are reproducing more quickly thus if a cancer forms it is harder to get rid of it fast enough to stop it from becoming a tumor. About 900 new cases occur each year in the United States and it also occur twice as much in males than females. The cause of this cancer is still unknown. Long bones are more afected than other bones in the body, such as flat bones in the skull and in the pelvis. In the leg this cancer arises the most, with the femur in the upper leg being the most commonly place for tumors, followed by the tibia in the lower leg and the humerus in the upper arm. The growth sites of the bones, which are at the ends of the long bones, are the locations where usually the cancer is situated. This cancer can develops after 7-15 years after treatment of another cancer most commonly retinoblastoma. It most commonly arises due to complications of the treatment . The complications with radiation often cause his cancer at the site of radiation. This cancer is associated with pain in the area which the cancer is present. The pain is caused by the limited movement in the are caused by the tumor in the area, or enlarged lymph nodes. Tenderness and increased heat in the affected area is often the point where parents get medical attencion for the young person affected. MRI's and x-ray images are used in the diagnosis of the cancer. X-rays allows the doctor to see the damage already done. They can see how far the cancer has gone in to the affected area. MRI's allow the doctor to see the actual extent of the cancer into the bone and the soft tissue around the end of the bone where the cancer has developed. Osteosarcoma can be mistaken for a benign tumor, as well as for other types of malignant tumor such as Ewing's sarcoma, so it is important to rule out these other possibilities during diagnosis. Other bone conditions such as osteochondroma, osteoid osteoma, osteoblastoma, and aneurysmal bone cyst can also be confused with osteosarcoma. Primary osteosarcoma must also be differentiated from metastatic bone tumors that are associated with another primary tumor. Finally, noncancerous conditions such as osteomyelitis, benign bone defects, and certain metabolic abnormalities involving the bone may require more specialized tests in order to be identified.(Steen and Mirro 419)

Under the microscope this cancer looks like a cluster of cells that are round, plump, or fusiform. The moe defined cells would have a more plasmacytoid look. The tumor would look like it has filaments coming out of it, like roots. These roots are what spread the cancer into other parts of the body.

There are supressor genes that take upon major roles in Osteosarcoma. Germline mutations of P53 were found in 3-4 percent of the children with Osteosarcoma. The P53 gene acts as a cell cycle control gene. It stops the transfected cell from entering the S phase. P53 acts as a checkpoint to stop the cell cycle from continuing and acepting any input from the body just to continue dividing. Also the greatest genetic disposition to Osteosarcoma is hereditary Retinoblastoma. The Rb gene was also found in many of the children that had Osteosarcoma, this gene is what causes Retinoblastoma. Retinoblastoma is a malignant tumor that arises in the back of the retina. It develops in the fetal stages or in early childhood. How Osteosarcoma is sometmes caused by complications with radiation during the healing process of Retinoblastoma, this gene can provoke two cancers.

Treatment of Osteosarcoma is usually individualized for each patient, depending on the site of the tumor, and the extent of the cancer into the bone. Often amputation is used if the cancer hasn\'t

spread, or also limb replacement. After the procedure chosen

is done(amputation or limb replacement) chemotherapy is given for about 6-12 weeks. Chemotherapy is used as long as the patient tolerates it affects.There are different chemicals used to give chemotherapy ( See apendix 1) Reliable Chemotherapy treatment has been available since 1973. Prognosis for the patient with osteosarcoma has improved considerably since chemotherapy was first used to prevent