Angiotropic melanoma and extravascular migratory metastasis: a review

Spontaneous migration of cancer cells under conditions of mechanical confinement

When cancer cells spread away from the primary tumor, they often follow the trajectories of lymphatic vessels, nerves, white matter tracts, or other heterogeneous structures in tissues. To better understand this form of guided cell migration we designed a series of microfluidic devices that mechanically constrain migrating cancer cells inside microchannels with cross-section comparable to cell size. We observed unexpectedly fast and persistent movement in one direction for several hours of cancer cells of different types. The persistent motility occurs spontaneously, in the absence of external gradients, suggesting the presence of intrinsic mechanisms driving cancer cell motility that are induced in conditions of mechanical confinement. To probe the mechanisms responsible for this behavior, we exposed cancer cells inside channels to drugs targeting the microtubules, and measured a significant reduction in the average migration speed. Surprisingly, a small number of cells appeared not to be affected by the treatment and displayed fast and persistent migration, comparable to the untreated cells. The new matrix-free, 3D-confined motility assay replicates critical interactions that cancer cells would normally have inside tissues, is compatible with high-content, high-throughput analysis of cellular motility at single cell level, and could provide useful insights into the biology of cancer cell migratory phenotype.

Conspicuous angiotropism of malignant melanoma involving the brain: implications for extravascular migratory metastasis

Angiotropism is the presence of tumor cells closely apposed to the abluminal surfaces of blood and lymphatic vessels without intravasation. Previous studies have strongly suggested that angiotropism in melanoma could be a marker for extravascular migratory metastasis, the migration of tumor cells along the external surfaces of vessels. We describe for the first time a patient with malignant melanoma of the brain most likely metastatic, which was floridly angiotropic as evidenced by extensive spread of melanoma cells along the external surfaces of brain microvessels. The location of this angiotropic melanoma in the brain, together with the analogies between extravascular migratory metastasis and the neoplastic glial invasion of the nervous system, reinforces the hypothesis of extravascular migration of melanoma cells as a means of tumor spread, particularly along the abluminal surfaces of vessels, in the brain and in other organs.

Melanoma prognostic factors found in the dermatopathology report

Significant prognostic information is available in a routine melanoma dermatopathology report. Features that are enumerated in the pathology report and that portend a potentially poorer prognosis are older age, site (acral, head, neck), male sex, increasing Breslow tumor thickness, increasing Clark's level, ulceration, increasing number of mitoses, vertical growth phase, regression, absence of a host inflammatory response, increased tumor vascularity, angiotropism, vascular invasion, neurotropism, marked atypia, and satellite metastasis.

Endoscopic ultrasound fine-needle aspiration detection of extravascular migratory metastasis from a remotely located pancreatic cancer

BACKGROUND & AIMS

Tumor cell migration along the periphery of blood vessels to remote sites has been termed extravascular migratory metastasis, which is distinct from direct gross tumor infiltration of blood vessels and from intravascular dissemination. Our objective was to report the presence of malignant perivascular cuffing of the celiac axis in a patient with an apparently early T stage and resectable pancreatic cancer.

METHODS

Case report is presented.

RESULTS

Endoscopic ultrasound (EUS) examination was performed with targeted fine-needle aspiration (FNA) of previously unrecognized perivascular cuffing by computed tomography, which established the presence of celiac axis malignant perivascular cuffing in the setting of a T1 pancreatic cancer.

CONCLUSIONS

EUS FNA might allow identification and tissue confirmation of otherwise unrecognized extravascular migratory metastasis. This finding suggests the potential for EUS FNA to further improve pancreatic cancer staging and to enhance patient care and outcomes.