| Metastasis Classification and external resources |
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| CT scan with metastatic tumour in lung (upper left lobe, seen on the right side of picture) | |
| DiseasesDB | 28954 |
| MedlinePlus | 002260 |
Metastasis (Greek: displacement, μετά=next + στάσις=placement, plural: metastases), sometimes abbreviated mets, is the spread of a disease from one organ or part to another non-adjacent organ or part. Greek (el ελληνική γλώσσα or simply el ελληνικά — "Hellenic" is an Indo-European language, spoken today by 15-22 million people mainly A disease is an abnormal condition of an organism that impairs bodily functions and can be deadly In Biology, an organ ( Latin: organum, "instrument tool" from Greek όργανον - organon "organ instrument Only malignant tumor cells and infections have the capacity to metastasize. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled See also Cancer A tumor or tumour is the name for a swelling or lesion formed by an abnormal growth of cells (termed neoplastic An infection is the detrimental Colonization of a host Organism by a foreign Species. Metastatic disease is a synonym of metastasis.
Cancer cells can "break away", "leak", or "spill" from a primary tumor, enter lymphatic and blood vessels, circulate through the bloodstream, and settle down to grow within normal tissues elsewhere in the body. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled Primary tumor is the nomenclature used when the Tumor has originated in the same organ and has not Metastasized to it In Anatomy, lymph vessels are thin walled Valved structures that carry Lymph. The blood vessels are part of the Circulatory system and function to transport Blood throughout the body This is an article about the rock music band "Circulatory System" Tissue is a cellular organizational level intermediate between cells and a complete organism Metastasis is one of three hallmarks of malignancy (contrast benign tumors). Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled A benign tumor is a Tumor that lacks all three of the Malignant properties of a Cancer. [1] Most tumors and other neoplasms can metastasize, although in varying degrees (e. See also Cancer A tumor or tumour is the name for a swelling or lesion formed by an abnormal growth of cells (termed neoplastic g. , glioma and basal cell carcinoma rarely metastasize). A glioma is a type of Cancer that starts in the brain or spine Basal cell carcinoma is a type of skin cancer It is a malignant epithelial cell tumor that begins as a papule (a small circumscribed solid elevation of the skin and enlarges peripherally developing [1]
When tumor cells metastasize, the new tumor is called a secondary or metastatic tumor, and its cells are like those in the original tumor. This means, for example, that, if breast cancer spreads (metastasizes) to the lung, the secondary tumor is made up of abnormal breast cells, not of abnormal lung cells. Breast cancer is a Cancer that starts in the cells of the Breast in women and men The tumor in the lung is then called metastatic breast cancer, not lung cancer.
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Modes and sites of metastatic dispersal
Metastatic tumors are very common in the late stages of cancer. The spread of metastases may occur via the blood or the lymphatics or through both routes. The most common places for the metastases to occur are the adrenals, liver, brain, and the bones. In Mammals the adrenal glands (also known as suprarenal glands) are the triangle-shaped Endocrine glands that sit on top of the Kidneys their The liver is a vital organ in the human body and is present in Vertebrates and some other animals The brain is the center of the Nervous system in animals All Vertebrates and the majority of Invertebrates have a brain Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce There is also a propensity for certain tumors to seed in particular organs. This was first discussed as the "seed and soil" theory by Stephen Paget over a century ago in 1889. Stephen Paget (1855-1926 was an English surgeon, the son of the distinguished surgeon and pathologist Sir James Paget, who has been long credited For example, prostate cancer usually metastasizes to the bones. In a similar manner, colon cancer has a tendency to metastasize to the liver. Colorectal cancer, also called colon cancer or large bowel cancer, includes Cancerous growths in the colon, Rectum and Stomach cancer often metastasizes to the ovary in women, then it is called a Krukenberg tumor. Stomach or gastric cancer can develop in any part of the Stomach and may spread throughout the stomach and to other organs particularly the Esophagus and "Ovaria" redirects here This is also a proposed section and a Synonym of Solanum. A Krukenberg tumor, also Krukenberg tumour, classically refers to a secondary ovarian malignancy whose primary site arose in the gastrointestinal tract It is difficult for cancer cells to survive outside their region of origin, so in order to metastasize they must find a location with similar characteristics.
For example, breast tumor cells, which gather calcium ions from breast milk, metastasize to bone tissue, where they can gather calcium ions from bone. An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge Malignant melanoma spreads to the brain, presumably because neural tissue and melanocytes arise from the same cell line in the embryo. Melanoma is a Malignant Tumor of Melanocytes which are found predominantly in skin but also in the Bowel and the Eye (see The nervous system is a Network of specialized cells that communicate information about an animal's surroundings and itself Melanocytes are cells located in the bottom layer (the Stratum basale) of the skin's epidermis and in the middle layer of the eye (the Uvea) Cell culture is the process by which prokaryotic, or eukaryotic cells are grown under controlled conditions An embryo (from Greek:, plural, lit "that which grows" from en- "in" + bryein "to swell be full" is a multicellular [2]
Cancer cells may spread to lymph nodes (regional lymph nodes) near the primary tumor. A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system. This is called nodal involvement, positive nodes, or regional disease. Localized spread to regional lymph nodes near the primary tumor is not normally counted as metastasis, although this is a sign of worse prognosis. A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system. Prognosis (older Greek πρόγνωσις modern Greek πρόγνωση - literally fore-knowing foreseeing) is a medical term denoting the
In addition to the above routes, metastasis may occur by direct seeding, e. g. , in the peritoneal cavity or pleural cavity. The peritoneal cavity is a potential space between the parietal Peritoneum and visceral peritoneum [1]
Factors involved
Metastasis is a complex series of steps in which cancer cells leave the original tumor site and migrate to other parts of the body via the bloodstream or the lymphatic system. To do so, malignant cells break away from the primary tumor and attach to and degrade proteins that make up the surrounding extracellular matrix (ECM), which separates the tumor from adjoining tissue. Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl In Biology, the extracellular matrix ( ECM) is the Extracellular part of animal tissue that usually provides structural support to the cells By degrading these proteins, cancer cells are able to breach the ECM and escape. When oral cancers metastasize, they commonly travel through the lymph system to the lymph nodes in the neck. Oral cancer is any cancerous tissue growth located in the Mouth. A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system. The body resists metastasis by a variety of mechanisms through the actions of a class of proteins known as metastasis suppressors, of which about a dozen are known. A metastasis suppressor is a protein that acts to slow or prevent Metastases (secondary Tumors from spreading in the body of an organism with Cancer. [3]
Cancer researchers studying the conditions necessary for cancer metastasis have discovered that one of the critical events required is the growth of a new network of blood vessels, called tumor angiogenesis. Angiogenesis is a physiological process involving the growth of new Blood vessels from pre-existing vessels [4] It has been found that angiogenesis inhibitors would therefore prevent the growth of metastases. An angiogenesis inhibitor is a substance that inhibits Angiogenesis (the growth of new blood vessels [1]
Metastasis and primary cancer
It is theorized that metastasis always coincides with a primary cancer, and, as such, is a tumor that started from a cancer cell or cells in another part of the body. However, over 10% of patients presenting to oncology units will have metastases without a primary tumor found. Oncology is the branch of medicine that studies Tumors ( Cancer) and seeks to understand their development diagnosis treatment and prevention In these cases, doctors refer to the primary tumor as "unknown" or "occult," and the patient is said to have cancer of unknown primary origin (CUP) or Unknown Primary Tumors (UPT). It is estimated that 3% of all cancers are of unknown primary origin. [5] Studies have shown that, if simple questioning does not reveal the cancer's source (coughing up blood -'probably lung', urinating blood - 'probably bladder'), complex imaging will not either. Lung cancer is a Disease of uncontrolled Cell growth in tissues of the Lung. Bladder cancer refers to any of several types of malignant growths of the Urinary bladder. [5] In some of these cases a primary may appear later.
The use of immunohistochemistry has permitted pathologists to give an identity to many of these metastases. Immunohistochemistry or IHC refers to the process of localizing proteins in cells of a tissue section exploiting the principle of antibodies binding specifically However, imaging of the indicated area only occasionally reveals a primary. In rare cases (e. g. , of melanoma), no primary tumor is found, even on autopsy. Melanoma is a Malignant Tumor of Melanocytes which are found predominantly in skin but also in the Bowel and the Eye (see It is therefore thought that some primary tumors can regress completely, but leave their metastases behind.
Common sites of origin
Diagnosis of primary and secondary tumors
The cells in a metastatic tumor resemble those in the primary tumor. Lung cancer is a Disease of uncontrolled Cell growth in tissues of the Lung. Breast cancer is a Cancer that starts in the cells of the Breast in women and men Melanoma is a Malignant Tumor of Melanocytes which are found predominantly in skin but also in the Bowel and the Eye (see Colorectal cancer, also called colon cancer or large bowel cancer, includes Cancerous growths in the colon, Rectum and "Kidney Cancer" redirects here For Wilms' Tumor/Nephroblastoma see Wilms' tumor. Pancreatic cancer is a malignant tumor of the Pancreas. Each year about 37680 individuals in the United States are diagnosed with this condition and 34290 Once the cancerous tissue is examined under a microscope to determine the cell type, a doctor can usually tell whether that type of cell is normally found in the part of the body from which the tissue sample was taken.
For instance, breast cancer cells look the same whether they are found in the breast or have spread to another part of the body. Breast cancer is a Cancer that starts in the cells of the Breast in women and men So, if a tissue sample taken from a tumor in the lung contains cells that look like breast cells, the doctor determines that the lung tumor is a secondary tumor. Still, the determination of the primary tumor can often be very difficult, and the pathologist may have to use several adjuvant techniques, such as immunohistochemistry, FISH (fluorescent in situ hybridization), and others. Immunohistochemistry or IHC refers to the process of localizing proteins in cells of a tissue section exploiting the principle of antibodies binding specifically FISH ( Fluorescent In situ hybridization) is a cytogenetic technique that can be used to detect and localize the presence or absence Despite the use of techniques, in some cases the primary tumor remains unidentified.
Metastatic cancers may be found at the same time as the primary tumor, or months or years later. When a second tumor is found in a patient that has been treated for cancer in the past, it is more often a metastasis than another primary tumor.
Treatments for metastatic cancer
Whether or not a cancer is local or has spread to other locations affects treatment and survival. If the cancer spreads to other tissues and organs, it may decrease a patient's likelihood of survival. However, there are some cancers (i. e. , leukemia, brain) that can kill without spreading at all. Leukemia or leukaemia (Greek leukos λευκός, "white" aima αίμα, "blood" is a Cancer of the Blood
When cancer has metastasized, it may be treated with radiosurgery, chemotherapy, radiation therapy, biological therapy, hormone therapy, surgery or a combination of these. Radiosurgery, also known as stereotactic radiotherapy is a Medical procedure which allows non-invasive treatment of benign and malignant conditions avascular malformations Chemotherapy, in its most general sense refers to treatment of disease by chemicals that kill cells specifically those of micro-organisms or Cancer. Radiation therapy (or radiotherapy) is the medical use of Ionizing radiation as part of Cancer treatment to control Malignant Immunotherapy in medicine refers to an array of treatment strategies based upon the concept of modulating the Immune system to achieve a prophylactic and/or Hormone therapy, or hormonal therapy is the use of Hormones in medical treatment Surgery (from the χειρουργική cheirourgikē, via chirurgiae meaning "hand work" is a medical specialty that uses operative manual and instrumental The choice of treatment generally depends on the type of primary cancer, the size and location of the metastasis, the patient's age and general health, and the types of treatments used previously. In patients diagnosed with CUP, it is still possible to treat the disease even when the primary tumor cannot be located.
The treatment options currently available are rarely able to cure metastatic cancer, though some tumors, such as testicular cancer, are usually still curable. Testicular cancer is Cancer that develops in the Testicles a part of the Male reproductive system
References
- ^ a b c d Kumar, Abbas, Fausto; Robbins and Cotran: Pathologic Basis of Disease; Elsevier, 7th ed.
- ^ Robert Weinberg, The Biology of Cancer, cited in Basics: A mutinous group of cells on a greedy, destructive task, by Natalie Angier, New York Times, April 3, 2007
- ^ Yoshida, BA, Sokoloff, MM, Welch, DR, Rinker-Schaeffer CW. 2000. Metastasis-suppressor genes: a review and perspective on an emerging field. Journal of the National Cancer Institute 92: 1717-1730.
- ^ N Weidner, JP Semple, WR Welch, and J Folkman; Tumor angiogenesis and metastasis--correlation in invasive breast carcinoma; The New England Journal of Medicine, Volume 324:1-8, January 3, 1991; Number 1.
- ^ a b Evangelos Briasoulis, Nicholas Pavlidis; Cancer of Unknown Primary Origin; The Oncologist, Vol. 2, No. 3, 142–152, June 1997
See also
External links
Medical information about metastatic cancer
- Q&A: Metastatic Cancer – from the National Cancer Institute
- Invasion and Metastases – from Cancer Medicine e. Disseminated disease refers to a diffuse Disease process generally either infectious or Neoplastic, but sometimes also referring to Connective tissue The National Cancer Institute (NCI is part of the United States Federal government's National Institutes of Health. 5
- How Cancer Grows and Spreads – an interactive Flash presentation that explores the progression of a carcinoma from a single cell to metastasis; from the research department of Children's Hospital Boston
- Metastasis photo at the Atlas of Pathology website
Charities and advocacy groups dealing with metastatic cancer
- The MetaCancer Foundation – resources and support for metastatic cancer survivors and their caregivers
- Metastatic Breast Cancer Network
- Children's Cancer Research Charity for Metastatic Cancer in Kids
Not specifically about metastatic cancer
- Understanding Cancer Types and Staging – a patients' guide at the CancerGuide website
- Cancer Forums – physicians answering questions about cancer
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