HOME

TheInfoList



OR:

Bone metastasis, or osseous metastatic disease, is a category of
cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...
metastases Metastasis is a pathogenic agent's spread from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, the ...
that results from primary tumor invasion to
bone A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, ...
. Bone-originating primary tumors such as
osteosarcoma An osteosarcoma (OS) or osteogenic sarcoma (OGS) (or simply bone cancer) is a cancerous tumor in a bone. Specifically, it is an aggressive malignant neoplasm that arises from primitive transformed cells of mesenchymal origin (and thus a sarcoma ...
, chondrosarcoma, and Ewing's sarcoma are rare; the most common bone tumor is a metastasis Bone metastases can be classified as
osteolytic Osteolysis is an active resorption of bone matrix by osteoclasts and can be interpreted as the reverse of ossification. Although osteoclasts are active during the natural formation of healthy bone the term "osteolysis" specifically refers to a pat ...
, osteoblastic, or both. Unlike hematologic malignancies which originate in the blood and form non-solid tumors, bone metastases generally arise from
epithelial Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellu ...
tumors and form a solid mass inside the bone. Bone metastases, especially in a state of advanced disease, can cause severe pain, characterized by a dull, constant ache with periodic spikes of incident pain.


Types of lesions

Under normal conditions, bone undergoes continuous remodeling through
osteoclast An osteoclast () is a type of bone cell that breaks down bone tissue. This function is critical in the maintenance, repair, and remodeling of bones of the vertebral skeleton. The osteoclast disassembles and digests the composite of hydrated pro ...
-mediated bone resorption and
osteoblast Osteoblasts (from the Greek language, Greek combining forms for "bone", ὀστέο-, ''osteo-'' and βλαστάνω, ''blastanō'' "germinate") are cell (biology), cells with a single Cell nucleus, nucleus that synthesize bone. However, in the p ...
-mediated bone deposition. These processes are normally tightly regulated within bone to maintain bone structure and calcium
homeostasis In biology, homeostasis ( British also homoeostasis) (/hɒmɪə(ʊ)ˈsteɪsɪs/) is the state of steady internal, physical, and chemical conditions maintained by living systems. This is the condition of optimal functioning for the organism and ...
in the body. Dysregulation of these processes by tumor cells leads to either osteoblastic or
osteolytic Osteolysis is an active resorption of bone matrix by osteoclasts and can be interpreted as the reverse of ossification. Although osteoclasts are active during the natural formation of healthy bone the term "osteolysis" specifically refers to a pat ...
lesions, reflective of the underlying mechanism of development. Typically, osteolytic metastases are more aggressive than osteoblastic metastases, which have a slower course. Regardless of the phenotype, bone metastases commonly show osteoclast proliferation and
hypertrophy Hypertrophy is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It is distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number.Updated by Linda J. ...
. Primary tumors * Osteoblastic lesions **
Prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that su ...
**
Carcinoid A carcinoid (also carcinoid tumor) is a slow-growing type of neuroendocrine tumor originating in the cells of the neuroendocrine system. In some cases, metastasis may occur. Carcinoid tumors of the midgut (jejunum, ileum, appendix, and cecum) ...
**
Small cell lung cancer Small-cell carcinoma is a type of highly malignant cancer that most commonly arises within the lung, although it can occasionally arise in other body sites, such as the cervix, prostate, and gastrointestinal tract. Compared to non-small cell ca ...
**
Hodgkin lymphoma Hodgkin lymphoma (HL) is a type of lymphoma, in which cancer originates from a specific type of white blood cell called lymphocytes, where multinucleated Reed–Sternberg cells (RS cells) are present in the patient's lymph nodes. The conditio ...
** Medulloblastoma * Osteolytic lesions **
Non-small cell lung cancer Non-small-cell lung cancer (NSCLC) is any type of epithelial lung cancer other than small-cell lung carcinoma (SCLC). NSCLC accounts for about 85% of all lung cancers. As a class, NSCLCs are relatively insensitive to chemotherapy, compared to s ...
**
Thyroid cancer Thyroid cancer is cancer that develops from the tissues of the thyroid gland. It is a disease in which cells grow abnormally and have the potential to spread to other parts of the body. Symptoms can include swelling or a lump in the neck. Ca ...
**
Kidney cancer Kidney cancer, also known as renal cancer, is a group of cancers that starts in the kidney. Symptoms may include blood in the urine, lump in the abdomen, or back pain. Fever, weight loss, and tiredness may also occur. Complications can include sp ...
**
Multiple myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, ...
**
Melanoma Melanoma, also redundantly known as malignant melanoma, is a type of skin cancer that develops from the pigment-producing cells known as melanocytes. Melanomas typically occur in the skin, but may rarely occur in the mouth, intestines, or eye ( ...
**
Non-Hodgkin lymphoma Non-Hodgkin lymphoma (NHL), also known as non-Hodgkin's lymphoma, is a group of blood cancers that includes all types of lymphomas except Hodgkin lymphomas. Symptoms include enlarged lymph nodes, fever, night sweats, weight loss, and tiredne ...
** Langerhans cell histiocytosis * Mixed lesions **
Breast cancer Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or ...
**
Testicular cancer Testicular cancer is cancer that develops in the testicles, a part of the male reproductive system. Symptoms may include a lump in the testicle, or swelling or pain in the scrotum. Treatment may result in infertility. Risk factors include a ...
**
Ovarian cancer Ovarian cancer is a cancerous tumor of an ovary. It may originate from the ovary itself or more commonly from communicating nearby structures such as fallopian tubes or the inner lining of the abdomen. The ovary is made up of three different ...
**
Gastrointestinal cancer Gastrointestinal cancer refers to malignant conditions of the gastrointestinal tract (GI tract) and accessory organs of digestion, including the esophagus, stomach, biliary system, pancreas, small intestine, large intestine, rectum and anus. Th ...
s ** Squamous cell skin cancers **
Hepatocellular carcinoma Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults and is currently the most common cause of death in people with cirrhosis. HCC is the third leading cause of cancer-related deaths worldwide. It occurs in t ...
s


Signs and symptoms

Bone metastases can cause severe pain,
bone fractures A bone fracture (abbreviated FRX or Fx, Fx, or #) is a medical condition in which there is a partial or complete break in the continuity of any bone in the body. In more severe cases, the bone may be broken into several fragments, known as a '' ...
,
spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the sp ...
compression,
hypercalcemia Hypercalcemia, also spelled hypercalcaemia, is a high calcium (Ca2+) level in the blood serum. The normal range is 2.1–2.6  mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), with levels greater than 2.6 mmol/L defined as hypercalcem ...
,
anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, t ...
, spinal instability, decreased mobility, and rapid degradation in the quality of life for patients. Patients have described the pain as a dull ache that grows worse over time, with intermittent periods of sharp, jagged pain. Even under controlled pain management, periods of
breakthrough pain Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...
can occur rapidly, without warning, several times a day. Pain may be worse at night and partially relieved by activity. Metastases to weightbearing bones may become symptomatic early in the course of disease, as compared to metastases to the flat bones of the rib or sternum. ; Effects of bone metastasis Major complications secondary to bone metastases are termed Skeletal-Related Events (SREs). * Occurrence of pathological long bone and vertebral fractures * Development of spinal cord compression * Need for radiation for pain relief or to treat or prevent pathological fractures or spinal cord compression * Requirement for surgery to bone * Episodes of
hypercalcemia Hypercalcemia, also spelled hypercalcaemia, is a high calcium (Ca2+) level in the blood serum. The normal range is 2.1–2.6  mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), with levels greater than 2.6 mmol/L defined as hypercalcem ...
of malignancy Other symptoms include: * Spinal Instability * Compression of the
Cauda Equina The cauda equina () is a bundle of spinal nerves and spinal nerve rootlets, consisting of the second through fifth lumbar nerve pairs, the first through fifth sacral nerve pairs, and the coccygeal nerve, all of which arise from the lumbar enlarg ...
* Cranial Nerve Palsies * Suppression of bone marrow function (i.e.
anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, t ...
) * Decreased mobility


Sources of bone metastases

Bone is the third most common location for
metastasis Metastasis is a pathogenic agent's spread from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, the ...
, after the
lung The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of ...
and
liver The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it i ...
. While any type of cancer is capable of forming metastatic tumors within bone, the microenvironment of the marrow tends to favor particular types of cancer, including
prostate The prostate is both an accessory gland of the male reproductive system and a muscle-driven mechanical switch between urination and ejaculation. It is found only in some mammals. It differs between species anatomically, chemically, and phys ...
,
breast The breast is one of two prominences located on the upper ventral region of a primate's torso. Both females and males develop breasts from the same embryological tissues. In females, it serves as the mammary gland, which produces and sec ...
, and
lung cancer Lung cancer, also known as lung carcinoma (since about 98–99% of all lung cancers are carcinomas), is a malignant lung tumor characterized by uncontrolled cell growth in tissues of the lung. Lung carcinomas derive from transformed, mali ...
s. In
prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that su ...
, bone metastases tend to be the only site of metastasis. The most common sites of bone metastases are the spine, pelvis, ribs, skull, and proximal femur. Common primary tumors *
Breast cancer Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or ...
*
Prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that su ...
*
Lung cancer Lung cancer, also known as lung carcinoma (since about 98–99% of all lung cancers are carcinomas), is a malignant lung tumor characterized by uncontrolled cell growth in tissues of the lung. Lung carcinomas derive from transformed, mali ...
*
Kidney cancer Kidney cancer, also known as renal cancer, is a group of cancers that starts in the kidney. Symptoms may include blood in the urine, lump in the abdomen, or back pain. Fever, weight loss, and tiredness may also occur. Complications can include sp ...
*
Thyroid cancer Thyroid cancer is cancer that develops from the tissues of the thyroid gland. It is a disease in which cells grow abnormally and have the potential to spread to other parts of the body. Symptoms can include swelling or a lump in the neck. Ca ...


Mechanism


Initial Seeding

Many cancers spread to bone, but not all bones are implicated in cancerous metastasis. The microenvironment of differing bone types is thought to play a role in its predisposition to tumor seeding.Fornetti, J., Welm, A.L. and Stewart, S.A. (2018), Understanding the Bone in Cancer Metastasis. J Bone Miner Res, 33: 2099-2113. https://doi-org.ucsf.idm.oclc.org/10.1002/jbmr.3618 For example, trabecular bone rich in red marrow and bone subject to frequent turnover are more likely to be seeded at ''premetastatic niches'' formed by interactions between cancerous cells and bone substrate Tumor cells are then attracted to the metastatic niche in the bone. However, the characteristics of these niches have yet to be fully elucidated. Initial seeding can occur prior to the discovery of the primary tumor.


Vascular Seeding

The pathogenesis of bone metastasis via the vasculature is hypothesized to be related to the Batson vertebral vein plexus, a longitudinal valveless system connected to the breast, lung, kidney, thyroid, and prostate gland that extends from the sacrum to the skull. The most common locations of metastases are the
pelvis The pelvis (plural pelves or pelvises) is the lower part of the trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis, or pelvic skeleton). The ...
,
vertebral bodies The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic i ...
,
ribs The rib cage, as an enclosure that comprises the ribs, vertebral column and sternum in the thorax of most vertebrates, protects vital organs such as the heart, lungs and great vessels. The sternum, together known as the thoracic cage, is a semi- ...
and ends of long bones.


Dormancy

Once established, the tumor cells can remain dormant on the bone microenvironment, radiologically undetectable, for many years. The triggers which eventually awaken metastatic tumor cells are an active field of study as they could elucidate mechanisms of controlling dormancy.


Tumor Cell-Bone Interactions

Tumor cells may have paraneoplastic effects, such as via the secretion of
Prostaglandin E Prostaglandin E is a family of naturally occurring prostaglandins that are used as medications. Types include: * Prostaglandin E1 also known as alprostadil * Prostaglandin E2 also known as dinoprostone Both types are on the World Health Orga ...
, TGF-alpha,
TGF-beta Transforming growth factor beta (TGF-β) is a multifunctional cytokine belonging to the transforming growth factor superfamily that includes three different mammalian isoforms (TGF-β 1 to 3, HGNC symbols TGFB1, TGFB2, TGFB3) and many other ...
, TNF, and
interleukin Interleukins (ILs) are a group of cytokines (secreted proteins and signal molecules) that are expressed and secreted by white blood cells (leukocytes) as well as some other body cells. The human genome encodes more than 50 interleukins and related ...
s to increase bone resorption. The destruction of bone affected by bone metastases are caused by
osteoclast An osteoclast () is a type of bone cell that breaks down bone tissue. This function is critical in the maintenance, repair, and remodeling of bones of the vertebral skeleton. The osteoclast disassembles and digests the composite of hydrated pro ...
-mediated
osteolysis Osteolysis is an active resorption of bone matrix by osteoclasts and can be interpreted as the reverse of ossification. Although osteoclasts are active during the natural formation of healthy bone the term "osteolysis" specifically refers to a pa ...
. The uncoupled regulation of
osteoclast An osteoclast () is a type of bone cell that breaks down bone tissue. This function is critical in the maintenance, repair, and remodeling of bones of the vertebral skeleton. The osteoclast disassembles and digests the composite of hydrated pro ...
s and
osteoblast Osteoblasts (from the Greek language, Greek combining forms for "bone", ὀστέο-, ''osteo-'' and βλαστάνω, ''blastanō'' "germinate") are cell (biology), cells with a single Cell nucleus, nucleus that synthesize bone. However, in the p ...
s leads to malformation of the bone. Lytic bone lesions may also lead to the pathogenesis of
hypercalcemia Hypercalcemia, also spelled hypercalcaemia, is a high calcium (Ca2+) level in the blood serum. The normal range is 2.1–2.6  mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), with levels greater than 2.6 mmol/L defined as hypercalcem ...
in cancers that have spread to bone


Diagnosis


Skeletal Radiography

A plain film
x-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10  nanometers, corresponding to frequencies in the range 30&nb ...
of the entire body can identify bone metastasis. However, the sclerotic or osteolytic lesions must be at least 1 cm in diameter. A combination of X-ray, CT and MRI scans may be most sensitive in the diagnosis of cancerous bone metastasis.


Radionuclide Bone Scan

A
radionuclide A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transfer ...
bone scan or
scintigraphy Scintigraphy (from Latin ''scintilla'', "spark"), also known as a gamma scan, is a diagnostic test in nuclear medicine, where radioisotopes attached to drugs that travel to a specific organ or tissue ( radiopharmaceuticals) are taken internally an ...
can identify bone metastasis. Technetium-99m–labeled
bisphosphonate Bisphosphonates are a class of drugs that prevent the loss of bone density, used to treat osteoporosis and similar diseases. They are the most commonly prescribed drugs used to treat osteoporosis. They are called bisphosphonates because they ...
attaches to calcium at sites of active bone formation. Bone scans are more sensitive and can identify lesions earlier than plain radiographs. However, these methods are less effective at identifying purely osteolytic lesions and will also highlight other areas of bone formation, such as those caused by trauma or inflammation unrelated to cancer. Additionally, bladder activity may mask the detection of certain pelvic lesions.


CT Scan

A CT scan can detect bone metastases before they present with symptoms in patients diagnosed with tumors that are high-risk for spread to the bone. Even sclerotic bone metastases are generally less radiodense than enostoses, and it has been suggested that bone metastasis should be the favored diagnosis between the two for bone lesions lower than a cutoff of 1060 Hounsfield units (HU). If a biopsy is indicated, a CT scan is often used to localize the lesion before biopsy.


MRI

MRIs can be used to detect bone metastasis with a sensitivity of 82-100% and a specificity of 73-100%.


PET Scan

Positron emission tomography Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, ...
(PET) with fluorine 18–labeled fluorodeoxyglucose ( 18 F-FDG) is a powerful diagnostic tool to visualize the activity of bone metastasis. Bone metastases on PET scan are usually multiple, irregularly distributed foci of increased tracer uptake without relationship to a single anatomic structure. A PET scan can directly identify tumor cells with significant metabolic rate. However, it is a costly procedure and device availability may be limited.


Bone Markers

Due to the high rate of bone turnover, metabolites are theorized to be capable of detecting bone metastasis. Use of bone markers for detection and screening is an active field of research, though radiographic evidence remains the gold standard. However, once the presence of a bone metastasis has been established, tumor metabolic markers can provide useful diagnostic and prognostic information.


Treatment

The goals of treatment for bone metastases include pain control, prevention and treatment of fractures, maintenance of patient quality of life, and local tumor control. Optimal treatment requires a multidisciplinary team of physicians, including medical and radiation oncologists, orthopedic surgeons, radiologists, nuclear medicine physician, palliative medicine specialists, and more. Assessment of treatment is determined by multiple factors, including performance status, pain score, impact on quality of life, and overall status of clinical disease. Important therapies include external-beam radiotherapy, targeted radioisotope therapy, image guided tumor ablation
chemotherapy Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs (chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemother ...
, and bone-targeting chemotherapeutic agents such as
Bisphosphonate Bisphosphonates are a class of drugs that prevent the loss of bone density, used to treat osteoporosis and similar diseases. They are the most commonly prescribed drugs used to treat osteoporosis. They are called bisphosphonates because they ...
s and Denosumab. Orthopedic interventions such as
internal fixation Internal fixation is an operation in orthopedics that involves the surgical implementation of implants for the purpose of repairing a bone, a concept that dates to the mid-nineteenth century and was made applicable for routine treatment in the ...
or
spinal decompression Spinal decompression is the relief of pressure on the spinal cord or on one or more compressed nerve roots passing through or exiting the spinal column. Decompression of the spinal neural elements is a key component in treating spinal radiculopath ...
may be necessary in the case of loss of structural stability due to bone destruction.


Pain management

The World Health Organization's pain ladder was designed for the management of cancer-associated pain. The original ladder details the management of pain using a sequence of analgesic medications, starting with non-steroidal anti-inflammatory medications and progressing to weak and strong
opioid Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid use ...
s Other treatments include
corticosteroid Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are inv ...
s,
radiotherapy Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is a therapy using ionizing radiation, generally provided as part of cancer treatment to control or kill malignant cells and normally delivered by a linear accelerator. Rad ...
, and radionucleotides. Percutaneous osteoplasty involves the use of bone cement to reduce pain and improve mobility. In
palliative therapy Palliative care (derived from the Latin root , or 'to cloak') is an interdisciplinary medical caregiving approach aimed at optimizing quality of life and mitigating suffering among people with serious, complex, and often terminal illnesses. Wit ...
, the main options are external radiation and radiopharmaceuticals. Thermal ablation techniques are increasingly being used in the palliative treatment of painful metastatic bone disease. Although the majority of patients experience complete or partial relief of pain following external radiation therapy, the effect is not immediate and has been shown in some studies to be transient in more than half of patients. For patients who are not eligible or do not respond to traditional therapies ( i.e.
radiation therapy Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is a therapy using ionizing radiation, generally provided as part of cancer treatment to control or kill malignant cells and normally delivered by a linear accelerator. Rad ...
,
chemotherapy Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs (chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemother ...
, palliative surgery,
bisphosphonate Bisphosphonates are a class of drugs that prevent the loss of bone density, used to treat osteoporosis and similar diseases. They are the most commonly prescribed drugs used to treat osteoporosis. They are called bisphosphonates because they ...
s or analgesic medications), thermal ablation techniques have been explored as alternatives for pain reduction. Several multi-center clinical trials studying the efficacy of
radiofrequency ablation Radiofrequency ablation (RFA), also called fulguration, is a medical procedure in which part of the electrical conduction system of the heart, tumor or other dysfunctional tissue is ablated using the heat generated from medium frequency alternati ...
in the treatment of moderate to severe pain in patients with metastatic bone disease have shown significant decreases in patient reported pain after treatment. These studies are limited, however, to patients with one or two metastatic sites; pain from multiple tumors can be difficult to localize for directed therapy. More recently,
cryoablation Cryoablation is a process that uses extreme cold to destroy tissue. Cryoablation is performed using hollow needles (cryoprobes) through which cooled, thermally conductive, fluids are circulated. Cryoprobes are positioned adjacent to the target in ...
has also been explored as a potentially effective alternative as the area of destruction created by this technique can be monitored more effectively by CT than radiofrequency ablation, a potential advantage when treating tumors adjacent to critical structures. A Cochrane review of calcitonin for the treatment of metastatic bone pain suggests calcitonin yields no significant benefit in the reduction of bone pain or improvements in quality of life.


Bone-Targeted Agents

Bone-Targeted Agents (BTAs) including
Bisphosphonate Bisphosphonates are a class of drugs that prevent the loss of bone density, used to treat osteoporosis and similar diseases. They are the most commonly prescribed drugs used to treat osteoporosis. They are called bisphosphonates because they ...
s and Denosumab, can interrupt osteoclast-mediated
osteolysis Osteolysis is an active resorption of bone matrix by osteoclasts and can be interpreted as the reverse of ossification. Although osteoclasts are active during the natural formation of healthy bone the term "osteolysis" specifically refers to a pa ...
. Osteoclast inhibitors, most frequently used in the treatment of osteoporosis, can allow for bone healing and delay complications. BTAs have been shown to decrease the incidence of Skeletal Related Events (SREs) like pathological fractures, thereby decreasing the need for surgical intervention or pain medication.


Prognosis

Many cancers are predisposed to metastasize to bone. The list below details the likelihood of a cancer, if in a stage of advanced metastasis, to have spread to bone at time of death: * Breast: 65-75% * Prostate: 65-75% * Thyroid: 60% * Kidney: 20-25% * Lung: 30-40% Given the high incidence of breast, lung and prostate cancer, these patients account for > 80% of patients with bone metastases. For patients with advanced metastatic disease involving the bone, median survival from the time of diagnosis of a bone metastasis varies by primary tumor type. A list is included below: * Breast: 19–25 months * Prostate: 12–53 months * Thyroid: 48 months * Kidney: 12 months * Lung: 6–7 months


See also

*
Bone tumor A bone tumor is an abnormal growth of tissue in bone, traditionally classified as noncancerous (benign) or cancerous (malignant). Cancerous bone tumors usually originate from a cancer in another part of the body such as from lung, breast, thyro ...


References


Further reading

* * * * {{Authority control Skeletal disorders Osseous and chondromatous neoplasia