Epithelioid sarcoma with muscle metastasis detected by positron emission tomography.
BACKGROUND
Epithelioid sarcoma is an uncommon high-grade sarcoma, mostly involving the extremities.


METHODS
A 33-year-old man was referred to our institute with a diagnosis of Volkmann's contracture with the symptom of flexion contracture of the fingers associated with swelling in his left forearm. Magnetic resonance imaging (MRI) showed abnormal signal intensity, comprising iso-signal intensity on T1- and high-signal intensity on T2-weighted images surrounding the flexor tendons in the forearm. Diagnosis of epithelioid sarcoma was made by open biopsy, and amputation at the upper arm was then undertaken. [18F]-2-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) detected multiple lesions with an increased uptake in the right neck, the bilateral upper arms and the right thigh, as well as in the left axillary lymph nodes, with maximum standardized uptake value (SUVmax) ranging from 2.0 to 5.5 g/ml. Magnetic resonance imaging confirmed that there was a lesion within the right thigh muscle which was suggestive of metastasis, even though the lesion was occult clinically.


CONCLUSIONS
Increased uptake on FDG-PET might be representative of epithelioid sarcoma, and for this reason FDG-PET may be useful for detecting metastasis. Muscle metastasis is not well documented in epithelioid sarcoma. Accordingly, the frequency of muscle metastasis, including occult metastasis, needs to be further analyzed.
Sakamoto
Akio
A
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Fukuoka, 812-8582, Japan. akio@med.kyushu-u.ac.jp
Jono
Osamu
O
Hirahashi
Minako
M
Oya
Masafumi
M
Iwamoto
Yukihide
Y
Arai
Ken
K
D000328:Adult; D001706:Biopsy; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D019042:Muscle Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D049268:Positron-Emission Tomography; D011859:Radiography; D019275:Radiopharmaceuticals; D012509:Sarcoma / Q000000981:diagnostic imaging* / Q000556:secondary; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18