Hyalinizing spindle cell tumor with giant rosettes: a distinctive tumor closely resembling low-grade fibromyxoid sarcoma

Am J Surg Pathol. 1997 Dec;21(12):1481-8. doi: 10.1097/00000478-199712000-00011.


We report the findings of 19 cases of a previously undescribed spindle cell tumor of soft tissues that resembles a low-grade fibromyxoid sarcoma but contains distinctive rosettelike structures. The tumors occurred principally as a painless, slowly growing, deeply situated mass of the proximal extremities in young to middle-aged adults (age range 14-65 years; mean 38). Although grossly circumscribed, the tumors had infiltrative borders microscopically and were composed of bland spindled cells situated in a hyalinized to myxoid stroma. The most characteristic feature of the tumor was scattered large rosettelike structures that often merged with serpinginous areas of dense hyalinization. The rosettes consisted of a central collagen core surrounded by a rim of rounded cells morphologically and immunophenotypically different from the cells of the spindled stroma. These cells expressed a number of antigens, including S-100 protein, neuron-specific enolase, and leu 22, in contrast to the stroma, which usually lacked these antigens. Of the 12 patients with available follow-up information, one patient treated with simple excision clinically developed local recurrence of the tumor 20 months after initial biopsy. No other recurrences were reported during the limited follow-up period, and no patient developed metastatic disease. However, the favorable prognosis of the patients in our series to date may relate to the limited follow-up period (approximately 3 years), as well as initial treatment by wide excision in nearly half of the patients. We regard the hyalinizing spindle cell tumor with giant rosettes as a distinctive type of low-grade fibroblastic tumor that with time may prove to behave similar to a low-grade fibromyxoid sarcoma and, hence, to represent an unusual variant thereof.

MeSH terms

  • Actins / analysis
  • Adolescent
  • Adult
  • Aged
  • Antigens, CD / analysis
  • Desmin / analysis
  • Diagnosis, Differential
  • Female
  • Fibroma / pathology
  • Fibroma / surgery
  • Fibrosarcoma / pathology*
  • Fibrosarcoma / surgery
  • Humans
  • Keratins / analysis
  • Male
  • Middle Aged
  • Neurilemmoma / pathology
  • Neurilemmoma / surgery
  • Peripheral Nervous System Neoplasms / pathology
  • Peripheral Nervous System Neoplasms / surgery
  • Retrospective Studies
  • S100 Proteins / analysis
  • Soft Tissue Neoplasms / classification
  • Soft Tissue Neoplasms / pathology*
  • Soft Tissue Neoplasms / surgery
  • Vimentin / analysis


  • Actins
  • Antigens, CD
  • Desmin
  • S100 Proteins
  • Vimentin
  • Keratins