Cancer

Cancer is a general term for a group of diseases that occur when there is an uncontrolled growth of abnormal cells in one or more organs or tissues of the body.

Cancer is one of the leading causes of death globally. The top cancer killers include lung cancer, colorectal cancer, breast cancer, prostate cancer, and pancreatic cancer. The most common types of cancer include prostate cancer, breast cancer, lung cancer, colorectal cancer, and bladder cancer.

Normally, the body’s cells that are old or damaged will stop dividing and die before they can become cancerous. These cells replaced by healthy young cells. Cancer occurs when a genetic mutation causes old or damaged cells to continue to divide and multiply uncontrollably. This results in the development of a malignant tumor or other abnormalities that interfere with the functioning of the affected organ or tissue. Left untreated, cancerous cells can continue to multiply and spread to other parts of the body and interfere with more of the body’s vital processes.

There are two main types of cancer. Primary cancer is the first type of cancer that develops. Secondary cancer is caused by a cancer that has begun in another part of the body and spreads to another site, such as primary lung cancer or breast cancer that spreads to the brain, causing secondary brain cancer.

Secondary cancer is also called metastatic cancer. Cancer can metastasize by growing directly into nearby tissues and organs or by spreading through the circulatory system or lymphatic system to other areas of the body.

The cause of cancer differs depending on the specific type of cancer. In general, cancer is caused by inherited genes that increase susceptibility to cancer and/or by environmental factors. Environmental factors include exposure to certain chemicals, such as chemicals found in pollution, smoking, and tobacco. Other environmental factors include specific viruses and bacteria, such as HPV, and/or exposure to excessive radiation, such as from the sun.

Risk factors for cancer vary depending on the specific type of cancer, but common risk factors include smoking, obesity, excessive alcohol consumption, engaging in unsafe sexual practices, having a family history of cancer and excessive exposure to the sun.

Symptoms and complications of cancer vary greatly between different types of cancer. For more details on key symptoms and complications, refer to symptoms of cancer.

Diagnosing cancer begins with taking a thorough personal and family medical history, including symptoms and risk factors for cancer. The diagnostic process also includes completing a thorough physical exam.

Diagnostic testing varies depending on the suspected type of cancer. Testing can include a combination of imaging tests, such as MRI, PET scan and/or CT scan, which use computer technology to create detailed pictures of the body. An angiogram may also be done to illuminate blood vessels that feed blood to a tumor.

Diagnostic testing generally also includes a biopsy. In a biopsy a sample of cells or tissues are taken from the tumor and examined under a microscope for the presence of cancer cells or abnormal changes in tissue that can lead to cancer. This will determine if a tumor is cancerous or benign.

A diagnosis of cancer can be missed or delayed because some symptoms of cancer are similar to symptoms of other conditions. For more information about other diseases, disorders and conditions that can mimic cancer, refer to misdiagnosis of cancer.

Cancer is most treatable and curable if it is caught in the earliest stages of the disease. The prognosis for people with cancer varies depending on the location and stage of advancement of the cancer, age of the patient, general health status, and other factors. For details about treatments, refer to treatment of cancer.

Cancer: Cancer is caused by an abnormal overgrowth of cells with more than 100 cancer subtypes depending on which cell grows. In many cancers, the cells clump together to form solid tumors, but in some the cells are dispersed around the blood stream (leukemia) or the lymphatic system (lymphoma).

Prognosis of cancer has improved greatly in modern times owing to treatment advances and early detection programs. However, although survival rates have improved, cancer still remains the 2nd top cause of death, second only to heart disese in the USA.

Misdiagnosis of cancer is naturally possible but not common if professional medical advice is sought, because physicians will usually perform comprehensive diagnostic testing if cancer is a possibility. Diagnostic tests have also improved in accuracy including newer tumor marker blood tests. Self-diagnosis of cancer is usually incorrect and quite common is for people to fear that they have cancer based on a symptom (e.g. weight loss, persistent cough, lumps, or frequent urination), only to find out they have other less severe conditions. On the other hand, sadly common is for people to have cancer but be unaware of it, because many types have a slow insidious onset without early symptoms. For this reason, regular screening for particular types of cancer is valuable in preventing severe cancer cases.

 

Cancer: Symptoms

The symptoms of cancer differ depending on the specific type of cancer. Symptoms also vary among individuals and are different depending on the stage of advancement of cancer, where it is located, and what types of organs and tissues are affected. There are often no symptoms in very early cancer.

Cancer: Treatments

The general goal of treatment of cancer is to bring about a complete remission of the disease, in which there is no longer any sign of the cancer in the body. The prognosis for people with cancer varies greatly depending on the specific type of cancer, location and stage of advancement of the cancer, age of the patient, general health status, and other factors.

Cancer: Misdiagnosis

A diagnosis of cancer can be delayed or missed because in early stages there may not be any symptoms. In addition, some symptoms of cancer can be vague and similar to symptoms of other diseases or conditions. For example, symptoms of brain cancer may mimic symptoms of a migraine headache or transient ischemic attack. Symptoms of breast cancer may resemble symptoms of mastitis.

Symptoms of Cancer

  • Cancer symptoms depend on the type of cancer but may include:
    • Abscess
    • Bowel symptoms
    • Bladder symptoms
    • Poorly healing skin sore

 

Treatments for Cancer

  • Treatments depend on the specific type of cancer but some types of treatments are common
  • Chemotherapy
  • Radiation therapy
  • Surgery
  • Biological therapy (immunotherapy)