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
Identifiers and Pagination:Year: 2011
First Page: 13
Last Page: 16
Publisher Id: TOORTHJ-5-13
Article History:Received Date: 30/7/2010
Revision Received Date: 30/8/2010
Acceptance Date: 2/9/2010
Electronic publication date: 7/1/2011
Collection year: 2011
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.
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.