Chapter14

Primary tumor

Tumor growing at the anatomical site where tumor formation began and proceeded to yield this mass.

Metastasis

Malignant growth forming at one site in the body, the cells of which derive from a malignancy located elsewhere in the body.

Intravasation

Process of invading a blood or lymphatic vessel from the surrounding tissue.

Extravasation

Process of leaving a blood or lymphatic vessel and invading the surrounding tissue

Micrometastases

A single cell or small clump of disseminated cancer cells that can be visualized only using one or another form of light microscopy.

Colonization

Proliferation of cells within a micrometastasis that leads to the formation of a macroscopic metastasis.

Tissue Factor

A cell surface glycoprotein expressed by many cell types in the body that interacts with clotting factors in the plasma, thereby initiating the coagulation cascade.

Macrometastases

A metastatic tumor of a size that allows it to be detected by a variety of clinically used imaging procedures and thus does not require microscopy for its detection.

Cytokeratin

Forms of the intermediate filament protein keratin that constitute part of the cytoskeleton of an epithelial cell.

Gastrulation

An early stage of embryogenesis in which cells of the outer ectodermal layer invaginate into the interior of the embryo, where they serve as precursors of the endodermal and mesodermal cell layers.

Motogenic

Referring to an agent or signal that stimulates cell movement or motility.

Lamellipodium

A broad, sheetlike ruffle extending from the plasma membrane into the extracellular space that is typically found at the leading edge of a motile cell.

Hematogenous

Depending upon or facilitated by circulating blood.

Surrogate marker

A measurable parameter, often a diagnostic parameter, that serves to indicate the behavior of another process whose behavior it parallels and reflects.

Uveal melanoma

A tumor arising from the melanocytes of the uvea, more specifically located in the iris, the ciliary body, or the choroids of the eye.

Tumor self-seeding

Process whereby circulating tumor cells originating in a primary tumor or in its derived metastases return to the primary tumor, in which they proceed to spawn new subpopulations of neoplastic cells.

Tropism

(1) Tendency of a cell to face or move toward a specific location or signaling source. (2) Tendency of a cell to migrate in a specific direction or, in the case of metastatic cancer, to appear to home to a specific tissue site in the body.

Vascular ZIP code

The display by the luminal surfaces of endothelial cells of specific proteins that reflect or are specific to the tissue in which the endothelial cells and the vessels they form reside; one theory of metastasis proposes that circulating cancer cells adhere to the vessel walls by recognizing the specific homing address created by these displayed proteins.

Osteoclast

Cell type of monocyte origin that functions to degrade and demineralize already-assembled bone.

Resorption

The osteoclast-mediated process of dissolving mineralized bone with attendant mobilization of calcium into the circulation.

Osteoblast

Mesenchymal cell type related to fibroblasts that constructs mineralized bone through the deposition of a collagenous matrix and apatite crystals.

Osteolytic

Referring to a bone lesion that involves localized dissolution of mineralized bone.

Osteoblastic

Referring to a class of bone lesions that involve localized increases in the amount of mineralized bone.

Osteoid

The extracellular matrix that forms during bone formation prior to mineralization.

Bisphosphonate

A class of drugs, characterized by a chemical backbone with the structure P–C–P, that are incorporated into bone apatite and subsequently become available to poison osteoclasts that might later dissolve the bone.

Hypercalcemia

Presence of elevated concentrations of calcium ions in the blood.