What is Cancer? Overview, Warning Signs, Symptoms, and Causes

Cancer is one of those words nobody wants to hear in diagnostic tests or their doctor’s appointments. For many of us, it is a synonym for severe disease, and people think it is impossible or very difficult to treat, which is sometimes right. In other cases, cancer is slow-growing and not a cause of death. Thus, therapeutic options are always laid down depending on the type of cancer, its stage, and the patient’s health and life expectancy.

Without a doubt, cancer is difficult to treat, and there is no single treatment for all types. Besides the location, every cancer has different features, including specific signs and symptoms, predisposing genes, and therapeutic options.

However, cancer does have many things in common regardless of the type and location. In this article, we’re reviewing those aspects in common, primarily focusing on the cause of cancer and the most common warning signs and symptoms to suspect the diagnosis of this disease.

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Most of us have heard about radiotherapy and chemotherapy as the leading cancer therapeutic approaches. They often prompt the image of baldness, weight loss, and other health problems. But what is cancer exactly? What causes cancer?

What is cancer?

Cancer Cells

Cancer is the clinical name given to the uncontrolled growth of cells in a given tissue. Sometimes this causes an increase in size and a tumor, but not always. There are also cancers without a solid tumor, and leukemia is one of the best examples.

We give cancer its name depending on the tissue that is involved. For example, breast cancer is the uncontrolled cell growth in the mammary duct tissue or the mammary glands.

As noted in the example of breast cancer, a single organ has different tissues and types of cells. Thus, cancer can be subdivided into different types depending on the cells involved in the malignant process. For example, in breast cancer, the breast has glandular tissue that synthesizes milk after pregnancy, and ductal tissue is made up of epithelium and its extracellular matrix, which supports functional tissue.

Depending on the type of tissue involved in uncontrolled growth, we can divide it into the following types:

  • Carcinoma: It is a prevalent type of cancer that originates in the internal or external lining of the skin or any other organ. It is subdivided into adenocarcinoma (cancer in glands) and squamous cell carcinoma (cancer in the epithelium).
  • Sarcoma: It is another common type of cancer that originates in connective tissue that supports organs and other tissues. It is given a name depending on the main tissue. For example, in the bones, it is called osteosarcoma, and in the skeletal muscle, it is called rhabdomyosarcoma.
  • Myeloma and leukemia: This type of cancer originates from the bone marrow cells or affects stem cells in various ways. Different from other types of cancer, leukemia does not always develop a tumor. Instead, it causes the overpopulation of cells in the blood.