Storiform

Storiform is a descriptive term used in histology and pathology to denote a pattern of cell arrangement in which spindle-shaped cells are organized in interlacing fascicles that radiate from a central point, producing a cartwheel- or woven-mat-like appearance. The name stems from the pattern’s resemblance to interlinked, woven strands.

The storiform pattern is most often discussed in the context of soft tissue neoplasms. It is classically described in dermatofibrosarcoma protuberans and fibrous histiocytoma (dermatofibroma), where spindle cells form intersecting, radial or whorled fascicles. Storiform architecture can also be observed in other spindle cell lesions and in certain inflammatory or fibrous conditions. Because many entities can exhibit a storiform arrangement, the pattern by itself is not diagnostic; interpretation depends on the full morphologic context and, when needed, ancillary studies.

Pathologists identify storiform patterns on light microscopy of hematoxylin and eosin–stained sections. In practice, recognition of this pattern aids differential diagnosis but must be integrated with clinical information and, if appropriate, immunohistochemical or molecular data to distinguish among similar-appearing lesions.

Related architectural patterns in spindle cell pathology include herringbone, fascicular, and whorled arrangements. Storiform thus serves as one of several descriptive tools used to characterize tissue architecture in histopathology.