A Rheumatoid Nodule Mimicking Soft Tissue Sarcoma on MR: A Case Report.
10.3348/jkrs.2000.42.2.349
- Author:
Joon il CHOI
1
;
Keun Young KONG
;
Heung Sik KANG
Author Information
1. Department of Radiology, Seoul National University College of Medicine and the Institute of Radiation Medicine, SNUMRC, Korea.
- Publication Type:Case Report
- Keywords:
Arthritis, rheumatoid;
Magnetic resonance (MR)
- MeSH:
Adult;
Arthritis, Rheumatoid;
Biopsy;
Diagnosis;
Diagnosis, Differential;
Female;
Humans;
Knee;
Middle Aged;
Rheumatoid Factor;
Rheumatoid Nodule*;
Sarcoma*;
Skin;
Subcutaneous Tissue
- From:Journal of the Korean Radiological Society
2000;42(2):349-352
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
We report a case of rheumatoid nodule of the right knee in a 55-year-old woman which on the basis of MR images was misdiagnosed as soft tissue sarcoma. Rheumatoid nodules occur in up to 20% of adult patients with rheumatoid arthritis and most patients with rheumatoid nodules are rheumatoid factor positive. The nod-ules are most commonly located between the skin and an underlying bony prominence. In this case, the patient had a history of rheumatoid arthritis and a soft tissue mass was present in the lateral aspect of the right knee. T1-weighted images revealed a mass of similar signal intensity to that of muscle, and on T2 weighted im-ages, a central portion of high signal intensity was noted. Enhanced T1 weighted images demonstrated periph-eral rim enhancement. The mass extended to subcutaneous tissue, with penetration of lateral patellar retinacu-lum. Excisional biopsy was performed, and the pathologic diagnosis was rheumatoid nodule. Although its radi-ologic findings are non-specific, rheumatoid nodule should - in appropriate clinical settings - be included in the differential diagnosis of a predominently solid or centrally necrotic periarticular soft tissue.
