RESEARCH ARTICLE


Malignant Pigmented Villonodular Synovitis in the Knee - Report of a Case with Rapid Clinical Progression



Naoaki Imakiire 1, Takashi Fujino 2, Takeshi Morii*, 1, Keita Honya 3, Kazuo Mochizuki 1, Kazuhiko Satomi 1, Yasunori Fujioka 2
1 Department of Orthopaedic Surgery, Kyorin University Faculty of Medicine. 6-20-2 Shinkawa Mitaka Tokyo 181-8611 Japan
2 Department of Pathology, Kyorin University Faculty of Medicine. 6-20-2 Shinkawa Mitaka Tokyo 181-8611 Japan
3 Department of Radiology, Kyorin University Faculty of Medicine. 6-20-2 Shinkawa Mitaka Tokyo 181-8611 Japan


© Imakiire et al.; Licensee Bentham Open.

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.

* Address correspondence to this author at the Department of Orthopaedic Surgery, Kyorin University Faculty of Medicine. 6-20-2 Shikawa Mitaka Tokyo 181-8611 Japan; Tel: +81-422-47-5511; Fax: +81-422-48-4206; E-mails: t-morii@gb3.so-net.ne.jp, t-morii@ks.kyorin-u.ac.jp


Abstract

Malignant pigmented villonodular synovitis (PVNS) (or malignant giant cell tumor of tendon sheath (GCTTS) is an extremely rare condition defined as a malignant lesion occurring with concomitant or previously documented PVNS at the same site. To date, only less than 20 cases have been reported in English literatures. We report a case of malignant PVNS in the knee in a 56-year-old woman with unpredictable rapid progression. This case raised a caution that when atypical components in specimens of recurrent benign PVNS are detected, even if low-grade or tiny, both pathologists and surgeons should consider the risk of malignant PVNS, which could display aggressive clinical progression.

Keywords: Soft tissue tumor, malignant pigmented villonodular synovitis, malignant giant cell tumor of tendon sheath.