Histologically, there are anastomosing
networks of blood vessels with highly atypical spindled cells that show enlarged, irregular hyperchromatic nuclei.
All of the cases described in those two series consisted of unilocular cysts, filled with lamellar keratin and exhibited minute, peripheral, anastomosing
Microscopically, at low-power magnification the tumors were composed of a compact anastomosing
capillary network supported in the edematous and myxoid background (Figure 2, A).
Pseudoangiomatous stromal hyperplasia is a rare, benign, breast stromal lesion that is classified under benign mesenchymal breast neoplasms in the WHO classification of breast disease.2 It is characterized by proliferation of stromal spindle cells with an intervening network of complex anastomosing
channels lined by slender spindle cells.
Current data indicate that this secondary modification of the pelvic kidney collecting ducts is restricted to salamanders with the complex anastomosing
pelvic kidney morphology; however, it must be recognized that kidneys from seasonal collections of salamanders exhibiting the nonanastomizing kidney morphology have not yet been investigated.
The histological features of ESFA are diagnostic and include multiple thin anastomosing
cords and strands of benign appearing epithelial cells which are connected to the undersurface of the epidermis and with or without formation of lumina which is embedded in a loose fibrovascular stroma.
In camels, the RERM had a spongy appearance, and consisted of a dense network of anastomosing
arteries occupying the entire cavity of the cavernous sinus.
The architectural patterns were quite variable from region to region, with neoplastic cells lining microcystic structures (Figure 1, A) or pseudoacini, or arranged in trabeculae or cords, anastomosing
in a plexiform or filigree pattern (Figure 1, B).
(8,10) Histologically, tumors contain a proliferation of ramifying and anastomosing
vascular channels that "dissect" through surrounding structures.
These branches leave the main trunk of the artery, pass between the two layers of mesentery, and form anastomosing
arches or arcades as they pass outward to supply the small intestine.
The following parameters regarding the branches of axillary artery were evaluated: (1) Locations; (2) origins; (3) diameters of the branches at their origin; (4) length of the branches; (5) courses; (6) distance between origin of the branches and lateral margin of the first rib; (7) anastomosing
and crossing patterns of the branches; (8) relations with the adjacent structures; (9) innervations and (10) the blood supplying patterns of the serratus anterior slips according to the muscle zones.
They display several growth characteristics: glandular spaces, trabeculae, festoons, ribbonlike patterns, anastomosing
cords, and solid sheets with variable cohesiveness.