metastasis

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Related to metastatic tumor: Cancer, metastasize

metastasis

1. Pathol the spreading of a disease, esp cancer cells, from one part of the body to another
2. a rare word for metabolism

Metastasis

 

a secondary pathological focus arising from the transfer of a pathogenic principle (tumor cells, infectious agent) from the primary site of affection by the lymph or blood.

In the modern view, the term “metastasis” generally applies to the spread (dissemination) of malignant tumor cells; the spread of an infectious principle is usually described by the term “metastatic infectious focus.”

Benign tumors are also known to metastasize, and the capacity to do so is inherent in normal cells of various origin (in placental villi, adipose and hematopoietic bone-marrow cells). A distinctive feature of metastasizing tumor cells is the uncontrollable growth of the metastasis, relating it to primary foci of malignant growth. Metastatic tumor nodes retain other properties of primary tumors as well, such as microstructural features and the capacity to form the same products; however, metastatic nodes often have a more primitive structure and consist of functionally less mature cells than do the original tumors.

When tumor cells spread chiefly through the lymphatic vessels, metastases generally appear in the lymph nodes closest to the primary site. Although much research has been devoted to the routes and anatomical patterns of lymphogenous metastasis, the biological patterns of formation of lymphogenous metastases remain obscure. The mechanisms of hematogenous metastasis (to the lungs, liver, bones, and other viscera) are better understood. Four stages in the development of hematogenous metastasis are distinguished: (1) the detachment of cells from the primary tumor node and their penetration of the blood through the vascular wall; (2) the circulation of the tumor cells in the blood; (3) the attachment of the cells to the vascular wall and the start of intravascular growth; and (4) the rupture of the vascular wall by the tumorous masses and the subsequent growth of the metastasis into the tissue of the affected organ. The presence of metastasis indicates that a tumorous process has shifted from a local growth phase to a phase of generalization. A distinction is made between solitary metastasis, which generally can be removed surgically, and multiple metastases, which require combined treatment using radiation and chemotherapy.

N. S. KISELEVA

metastasis

[mə′tas·tə·səs]
(medicine)
Transfer of the causal agent (cell or microorganism) of a disease from a primary focus to a distant one through the blood or lymphatic vessels.
(physics)
A transition of an electron or nucleon from one bound state to another in an atom or molecule, or the capture of an electron by a nucleus.
References in periodicals archive ?
Metastatic tumors to the oral and maxillofacial region: A retrospective study of 19 cases in West China and review of the Chinese and English literature.
Because many different targeted drugs were being used for different tumor types, finding the exact primary focus of the metastatic tumors is necessary in oncology practice.
Breast carcinoma, pulmonary carcinoma and prostatic cancer are the most common primary lesions for patients with bone metastasis tumors.1,2 Patients with spinal metastatic tumors usually have clinical manifestations such as intense pain, neurological disorders and paralysis, which brings huge pains for patients and also severely affects the living quality and survival period of patients.3
Patients with a high Cav-1 metastatic tumor showed significantly higher LNR levels (0.229 [+ or -] 0.195) compared to those with low metastatic tumoral Cav-1 expression (0.416 [+ or -] 0.255, P = 0.015).
We reported a case of metastatic tumors of the pancreas arising from RCC at a long-term follow-up after curative nephrectomy.
Furthermore, it is important to remark that metastatic tumors originating from primary kidney masses are highly vascularized and surgeons should expect significant haemorrhage during surgical removal.
After radical prostatectomy, radiation, cryotherapy, chemotherapy, or other treatments, CSCs remaining in the tissue or in the circulation may induce the development of recurrent or metastatic tumors. As most cancer therapies cause DNA damage in rapidly dividing cells or target hormonal or signaling pathways, they may not affect CSCs which are functionally different from the bulk tumor cells [66].
Contrastingly, both wtIL15 and ttIL15 equally inhibited metastatic tumor growth in the K7M3 osteosarcoma model (Figure 3(a)).
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Administered clinically by simple intravenous infusion, the Epeius tumor-targeted gene delivery system enables Rexin-G to seek out and accumulate selectively in cancerous tissues and remote metastatic tumor nodules that have spread throughout the body.
As tumor cells begin to aggregate, they form homotypic clumps, consisting only of potentially metastatic tumor cells, or heterotypic clumps, consisting of tumor cells, platelets and lymphocytes.
(2005) inferred that tungsten somehow played a role in the Fallon leukemias while presenting data suggesting that implanted tungsten alloy caused metastatic tumor formation, readers may confuse the issues and assume that somehow the two effects (rhabdomyosarcoma and childhood leukemia) are related.