Low-grade myofibroblastic sarcoma of the distal femur.

Abstract

INTRODUCTION:

Low-grade myofibroblastic sarcoma (myofibrosarcoma) is described to be a distinct atypical myofibroblastic tumor often with fibromatosis-like features and predilection for head and neck. Low-grade myofibroblastic sarcoma of bone is extremely rare.

PRESENTATION OF CASE:

A 50-year-old woman was admitted to our hospital because she had experienced right knee pain for 2 years. Plain radiography showed a honeycombed lesion on the right distal femur, and computed tomography showed a bone tumor with cortex destruction invading the soft tissue. A biopsy specimen from the intraosseous lesion showed a hypocellular area of spindle cell proliferation with dense collagen deposition, which is reminiscent of a histological feature of desmoplastic fibroma. However, histological examination of the extraosseous lesion indicated a slightly hypercellular area containing scattered spindle-shaped atypical cells with enlarged nuclei, suggestive of low-grade sarcoma. Spindle-shaped atypical cells were immunohistochemically positive for SMA. A final diagnosis of low-grade myofibroiblastic sarcoma of the bone was made from a surgically resected specimen.

DISCUSSION:

The patient was alive and well with no evidence of disease at 15 months after the surgery without any additional therapy.

CONCLUSION:

Extensive sampling of a tumor may be necessary to determine the true nature of the tumor and to make an accurate diagnosis.

• Authors: Tsuyoshi Saito, Hiroyuki Mitomi, Aiko Kurisaki, Tomoaki Torigoe, Tatsuya Takagi, Yoshiyuki Suehara, Taketo Okubo, Kazuo Kaneko, Takashi Yao
• Journal: International journal of surgery case reports (Int J Surg Case Rep) Vol. 4 Issue 2 Pg. 195-9 ( 2013) ISSN: 2210-2612 [Print] Netherlands
• PMID: 23276766 (Publication Type: Journal Article)
• Copyright: Copyright © 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.