What is meant in the pathology report that the stained tumor cells tended to "palisade around the periphery"?

Tumor cell pattern: Tumor cells grow in different patterns. One of the tools that pathologists use to identify different types of tumors is the pattern that the cells grow together. A peripheral palisading pattern is one where the majority of the cell nuclei are lined up at the outside edge of the tumor and there less cells in the center.

Description: Of the tumor under the microscope is part of pathology, but light microscopy patterns are being replaced by markers that define the tumor source, and help provide prognostic information. The art of description is fading, for the boring brown of immunohistochemistry. Clear spaces used to be pas+ for glycogen, or mucicarmine+ for fat. Some moderns mix this up.