Pathology of desmoid tumors

Desmoid fibromatosis is an uncommon locally aggressive fibroblastic/myofibroblastic neoplasm with no metastatic ability. The pathologic diagnosis is usually straightforward but can be difficult in small biopsies and in recurrences associated with scars from a prior procedure. Immunohistochemistry, specifically ß-catenin, and more recently, molecular diagnostics can play an important role in its diagnosis. This chapter reviews the clinical and pathological features, highlights the role of immunohistochemistry and molecular studies in distinguishing desmoids from potential mimics, and briefly discusses the clinical behavior with reference to possible predictors of recurrence.