Cancer is a type of tumor: a malignant neoplasm that originates in epithelial tissue. "Neoplasm" is a broader term, encompassing both benign and malignant tumors. Among malignant tumors, in addition to carcinomas, it also includes sarcomas, lymphomas, and leukemias. In everyday speech, these two words are used interchangeably, but in medicine, they mean different things. All cancers are neoplasms, but not all neoplasms are cancer.
To sum it up
- Cancer - is an abnormal, excessive growth of cells that does not meet the needs of the body; it can be benign or malignant.
- Cancer always represents a malignant tumor of epithelial origin (for example, lung cancer, breast cancer, colon cancer).
- Sarcoma, lymphoma and leukemia — these are malignant tumors, but not cancerous diseases, since they arise in other tissues.
- Cone - It is simply a noticeable or visible thickening and does not always mean cancer.
Are cancer and tumor the same thing?
No. Cancer (lat. neoplasm ) is abnormal tissue whose cells divide uncontrollably and do not obey the mechanisms that regulate the body's normal functioning. This name is given to a whole group of diseases.
Cancer (lat. carcinoma ) is a narrower term: a malignant tumor arising from epithelium , tissue covering the body's surface and lining organs and cavities, such as the bronchi, gastrointestinal tract, milk ducts, or prostate gland. Carcinomas constitute the largest and best-known group of malignant tumors, so their name has come to be commonly applied to all neoplastic diseases.
The English language only adds to the confusion: the word cancer refers to any malignant tumor, not just "karna" in the strict Polish sense. Therefore, in translations, the word "rak" is sometimes used in a broader sense than is implied by medical terminology.
Benign and malignant tumor
The main classification of cancer diseases is divided into benign (non-cancerous) и malignant . Both types grow uncontrollably, but behave differently.
- benign tumor Typically grows slowly, is clearly demarcated from surrounding tissues (often surrounded by a capsule), and does not invade adjacent tissues or metastasize. Examples include lipoma and fibroma.
- Malignant tumor penetrates and destroys surrounding tissues, can recur after removal and – most importantly – can metastasize , that is, spread through the blood or lymph to other organs.
«"Benign" doesn't always mean "harmless." A benign tumor can compress important structures, such as the skull, and require treatment. However, some growths, such as colon adenomas (polyps), are considered precancerous—most colon cancers develop from these growths, so they are removed during a colonoscopy.
What malignant tumors are not cancer?
Malignant tumors are classified primarily by the type of fabric from which they come . In addition to carcinomas, these include:
- Sarcomas arise from mesenchymal cells that form tissues such as adipose tissue, muscle, fibrous tissue, cartilage , bone and blood vessel walls. These are malignant tumors, but they should not be called cancer.
- Lymphomas — malignant neoplasms of immune system cells (lymphocytes), developing primarily in the lymph nodes.
- Leukemia — malignant neoplasms of the hematopoietic system that develop in the bone marrow.
- Tumors of the central nervous system , for example, gliomas.
- Melanoma – a malignant tumor that arises from pigment cells (melanocytes), and not from the epithelium.
Carcinoma in situ and invasive cancer
The diagnosis often includes the term «"carcinoma in situ"» (Latin for "in situ"). This refers to early-stage cancer, when cancer cells remain within the epithelium and have not yet crossed the basement membrane separating the epithelium from deeper tissues. At this stage, the cancer does not invade surrounding tissues or metastasize.
When cells break through the basement membrane, it is called invasive cancer , which can spread to the lymph nodes and other organs. This is why screening tests like Pap smears and colonoscopies are so important: they allow us to detect changes before they become invasive. Talk to your family doctor about which preventative tests are recommended for your age.
Cancer, tumor, tumor - comparison table
| Characteristic | Tumor | Cancer | Tumor |
|---|---|---|---|
| Scope of the concept | A whole group of diseases characterized by uncontrolled cell growth. | One of the types of malignant tumors | Any lump or growth of tissue |
| Is it always done with malicious intent? | No – it can be either harmless or malicious. | Yes, always. | No, it may not be cancer. |
| Fabric of origin | Any | Epithelium | Any (including cyst, inflammation) |
| Metastases | Malignant tumors only | This can give | It depends on the diagnosis. |
| Latin name | neoplasm | carcinoma | tumor |
| Examples | Lipoma, sarcoma, lymphoma, cancer | Lung, breast, prostate, and colon cancer | Lipoma, cyst, abscess, tumor |
Tumor and cancer – how to understand the diagnosis?
«"Consolidation"» A lump is a descriptive term: it refers to a mass that can be felt or seen on an X-ray. A lump may be a tumor, a cyst, an enlarged lymph node due to infection, or a lesion of inflammation. However, some cancers, such as most forms of leukemia, do not form masses at all.
As a rule, the malignancy of the formation and its type are determined histopathological examination — microscopic analysis of a tissue sample. Only this allows us to accurately identify the disease (e.g., adenocarcinoma, sarcoma, lymphoma) and choose the appropriate treatment. If you notice a worrisome lump, skin lesion, or other persistent symptoms, consult a doctor—only they can prescribe the necessary diagnostic tests.
Frequently Asked Questions (FAQ)
Is every tumor cancer?
No. Only malignant tumors of epithelial origin are called cancer. Benign tumors, sarcomas, lymphomas, and leukemia are not cancer, although they are often called that in common parlance.
Are there benign malignant tumors?
No. Cancer, by definition, is a malignant tumor. A tumor can be benign, but not cancerous.
Is sarcoma cancer?
No. Sarcoma is a malignant tumor, but it arises from tissues of mesenchymal origin (e.g., muscle, fat, bone), not from epithelial tissue, which is why it is not called cancer.
Does a lump always mean cancer?
No. A tumor is any thickening or growth of tissue; it can be a cyst, an inflammatory lesion, a benign or malignant tumor. The nature of the lesion is determined by a doctor based on tests, most often histopathological.
What is the difference between a benign and a malignant tumor?
A benign tumor typically grows slowly, has clear boundaries, and does not metastasize. A malignant tumor invades adjacent tissues and can recur and metastasize to other organs.
See also
- What is the difference between the circulatory and lymphatic systems?
- What is the difference between an animal cell and a plant cell?
- What is the difference between the abdomen and the stomach?
- What is the difference between smooth and striated muscle?