|Year : 2015 | Volume
| Issue : 1 | Page : 87-90
Giant cell tumors of the tendon sheath: Sonographic and magnetic resonance findings
Guneet Singh, Abhijit Patil, Harsh Kumar, Vilas Kulkarni
Department of Radiodignosis, Padmashree Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth, Pimpri, Pune, Maharahtra, India
|Date of Web Publication||8-Jan-2015|
3-B, Khalsa College Colony, Patiala - 147 001, Punjab
Source of Support: None, Conflict of Interest: None
Giant cell tumors of the tendon sheath (GCTTS) are the second most common tumor affecting the hand. Lesions are often solitary, painless, slow growing, and sub-cutaneous masses. We present here a case of GCTTS involving the dorsal aspect of little finger with sonographic and magnetic resonance findings favoring the disease, which was further confirmed by biopsy. Most of the cases mentioned previously in literature however show these tumors to occur more commonly on the volar aspect whenever there is involvement of the hand.
Keywords: Extensor tendon, giant cell tumors of the tendon sheath, proximal phalanx
|How to cite this article:|
Singh G, Patil A, Kumar H, Kulkarni V. Giant cell tumors of the tendon sheath: Sonographic and magnetic resonance findings. Med J DY Patil Univ 2015;8:87-90
| Introduction|| |
Giant cell tumors of the tendon sheath (GCTTS) of the tendon sheath is a benign synovial tumor of unknown etiology and is a rare entity.  It is considered to be a form of focal pigmented villonodular proliferative synovitis and has similar histological findings. These lesions are usually found in the tendon sheaths of the hand and wrist and less commonly in those of the ankle and feet. The lesion is commonly seen to affect the volar aspect of the involved digit.  There is slight female (64.3%) predominance noted. The age of distribution is 8-80 years but is more commonly diagnosed between 30 and 50 years.  They usually present as painless and nontender lesions that do not interfere with the movements of the involved joint and only rarely erode the underlying bone.
| Case Report|| |
A 26-year-old male patient presented with solitary soft tissue swelling in the dorsal aspect of the right little finger, which he noticed following blunt trauma 3 months back. The swelling was initially painful and small, which later gradually increased to the present size.
On examination, the lesion was poorly defined and nontender to touch and appeared to be attached to the extensor tendon. There were no local signs of inflammation.
Plain radiographs [Figure 1]a and b showed soft tissue swelling around the proximal phalanx of the little finger. The underlying dorsal cortex of the proximal phalanx showed subtle scalloping. The surrounding metacarpo-phalangeal and inter-phalangeal joints were normal.
Ultrasonography: [Figure 2]a and b A hypoechoic focal soft tissue lesion measuring approximately 2.6 cm (cranio-caudal) × 1.5 cm (transverse) × 0.3 cm (antero-posterior) was seen extending from metacarpo-phalangeal joint to proximal inter-phalangeal joint of the right little finger beneath the extensor tendon. The underlying bony cortex and joint appeared normal.
|Figure 2: A hypoechoic focal soft tissue lesion which was seen extending from metacarpo-phalangeal joint to proximal inter-phalangeal of the right little fi nger beneath the extensor tendon with normal underlying bony cortex and joints (a) (grey scale image) and (b) (color image)|
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Subsequently magnetic resonance right hand was done for the patient, which showed an altered signal intensity lesion measuring approximately 0.6 cm (antero-posterior) × 1.9 cm (transverse) × 3 cm (cranio-caudal) over the dorsal aspect of the right little finger extending from metacarpo-phalangeal joint to proximal inter-phalangeal joint involving the extensor tendon. It appeared hypointense on T1-weighted [Figure 3]a and b and T2-weighted [Figure 4]a-c, hyperintense on proton density fat-saturated [Figure 5]a and b and showed uniform postcontrast enhancement [Figure 6]a and b without any underlying marrow signal abnormality. Minimal sub-cutaneous edema was seen in the dorsal aspect of the little finger over the lesion. The metacarpo-phalyngeal joint and the proximal inter-phalangeal joints appear normal without any joint effusion.
|Figure 3: An altered signal intensity lesion over the dorsal aspect of the right little fi nger extending from metacarpo-phalangeal joint to proximal inter-phalangeal joint involving the extensor tendon which appeared hypointense on T1-weighted (a) (sagittal T1-weighted) and (b) (axial T1-weighted)|
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|Figure 4: An altered signal intensity lesion over the dorsal aspect of the right little fi nger extending from metacarpo-phalangeal joint to proximal inter-phalangeal joint involving the extensor tendon which appeared hypointense on T2-weighted (a) (coronal T2-weighted), (b) (sagittal T2-weighted) and (c) (axial T2-weighted)|
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|Figure 5: An altered signal intensity lesion over the dorsal aspect of the right little fi nger extending from metacarpo-phalangeal joint to proximal inter-phalangeal joint involving the extensor tendon which appeared hyperintense on proton density fat-saturated (PD fs) (a) (axial PD fs) and (b) (sagittal PD fs)|
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|Figure 6: Uniform postcontrast enhancement (a) (sagittal T1-weighted postcontrast image) and (b) (axial T1-weighted postcontrast image)|
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Biopsy [Figure 7] showed that the sample largely consisted of round to oval cells with pale nuclei and scanty cytoplasm. There was no significant mitosis seen. There were numerous benign giant cells (multinucleated). The stroma showed cleft like spaces and peri-vascular collection of inflammatory cells was also noted. These findings were suggestive of Giant cell tumor of tendon sheath.
|Figure 7: Biopsy showing large round to oval cells with pale nuclei and scanty cytoplasm along with numerous benign giant cells. The stroma is showing cleft like spaces and peri-vascular collection of infl ammatory cells. There was no signifi cant mitosis seen|
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| Discussion|| |
Giant cell tumor of the tendon sheath is a benign tumor, presenting as the second most common mass of the hand after ganglion cysts.  This entity has been referred to by multiple names, including localized nodular tenosynovitis, pigmented villonodular tenosynovitis, benign synovioma, giant cell fibrohemangioma and fibrous histiocytoma. The multiple nomenclatures indicate disagreement to the etiology of giant cell tumors.  Malignant changes are rare, though reports with pigmented villonodular synovitis do exist. In most reports, GCTTS involve predominantly palmar surface of the fingers more often than the dorsal surface.  However, Ushijima et al.  and Jones et al.  in their study have reported dorsal tumors to be more prevalent. This was true in our patient as the lesion was on the dorsal aspect of the right little finger along the extensor tendon. Because the lesions arise from the tendon sheath, close contact with a tendon is expected as seen in our case.
Histologically these tumors contain histiocyte like foamy or multinucleated giant cells and fibroblast like cells and may have hemosiderin deposits. Pathologically, giant cell tumors are identical to pigmented villonodular synovitis. Some lesions can be cellular and show atypical nuclei, but mitotic activity is usually absent. 
No characteristic radiographic appearance is seen with GCTTS. Radiographic findings are soft tissue mass in the majority of cases. Occasionally, they may cause pressure erosions and scalloping on the underlying bone.
Sonography also describes the relationship of the lesion to the surrounding structures. Information regarding the extent of contact with underlying tendon and the percentage of circumferential involvement is possible with sonography. Sonography shows a solid, homogeneous, hypoechoic mass generally in relation to the flexor tendons of the fingers, with increased vascularity on Doppler studies.  The lesion in our study was also homogenous and hypoechoic, however it was in relation to extensor tendon and showed no significant vascularity on Doppler study. No calcifications were seen.
Magnetic resonance imaging (MRI) typically shows a well-defined mass adjacent to or enveloping a tendon. Characteristically, the mass reveals decreased signal intensity on T1-weighted and usually low signal on T2-weighted weighted images. Blooming artifact may occur with gradient echo sequences. There may be areas of low signal and high signal on T2-weighted images due to the presence of hemosiderin and fluid respectively. Uniform enhancement can be seen postintravenous gadolinium. 
The differentials considered for a soft tissue swelling around the phalanx of the finger were ganglion cyst, tubercular tenosynovitis, periosteal chondroma and glomus tumor. Sonography is useful to distinguish between the localized GCTTS and the ganglion cyst by showing the generally cystic appearance of the ganglion cyst. However, one pitfall which has been described in the literature was that of a ruptured ganglion cyst, which could appear solid and mimic GCTTS.  Tubercular tenosynovitis generally demonstrates soft tissue swelling on plain radiograph, osteopenia can be observed indicating areas of hyperemia. On MRI serous exudates can be seen along the tendon appearing hyperintense on T2-weighted images.  Underlying involvement of the bone seen as marrow edema is commonly associated and isolated involvement of the tendon is rare. Periosteal chondroma appears as soft tissue mass with calcification in nearly half cases and pressure erosion of adjacent cortical bone seen in almost all plain radiographs. On MRI signal intensity of cartilaginous tumor tissue is typically hypo-or isointense relative to muscle on T1-weighted and hyperintense relative to fat on T2-weighted.  A rare differential of glomus tumor around proximal phalanx appear hyperintense on T2-weighted images in contrast to GCTTS, which has a low signal on T2-weighted images and is commonly subungual in location. 
| Conclusion|| |
Soft tissue lesions with involvement of the tendon and tendon sheaths with hypointense appearance on T1-weighted and T2-weighted with uniform postcontrast enhancement are sufficient for diagnosis of GCTTS. There have been studies showing common involvement of the flexor tendons by GCTTS, whereas some studies showed that extensor tendons were commonly involved as seen in our case. Hence possibility of GCTTS should always be kept in mind for soft tissue lesions of the digits in relation to the tendons.
| References|| |
Fotiadis E, Papadopoulos A, Svarnas T, Akritopoulos P, Sachinis NP, Chalidis BE. Giant cell tumour of tendon sheath of the digits. A systematic review. Hand (N Y) 2011;6:244-9.
Murphey MD, Rhee JH, Lewis RB, Fanburg-Smith JC, Flemming DJ, Walker EA. Pigmented villonodular synovitis: Radiologic-pathologic correlation. Radiographics 2008;28:1493-518.
Ushijima M, Hashimoto H, Tsuneyoshi M, Enjoji M. Giant cell tumor of the tendon sheath (nodular tenosynovitis). A study of 207 cases to compare the large joint group with the common digit group. Cancer 1986;57:875-84.
Jones FE, Soule EH, Coventry MB. Fibrous xanthoma of synovium (giant-cell tumor of tendon sheath, pigmented nodular synovitis). A study of one hundred and eighteen cases. J Bone Joint Surg Am 1969;51:76-8.
Rosenberg A. Bones, joints, and soft tissue tumors. In: Cotran RS, Kumar V, Collins T, editors. Robbins Pathologic Basis of Disease. 6 th
ed. Philadelphia: Saunders; 1999. p. 1258.
Middleton WD, Patel V, Teefey SA, Boyer MI. Giant cell tumors of the tendon sheath: Analysis of sonographic findings. AJR Am J Roentgenol 2004;183:337-9.
Wu JS, Hochman MG. Soft-tissue tumors and tumorlike lesions: A systematic imaging approach. Radiology 2009;253:297-316.
Sanders CJ, Schucany WG. Tuberculous tenosynovitis. Proc (Bayl Univ Med Cent) 2008;21:71-2.
Woertler K, Blasius S, Brinkschmidt C, Hillmann A, Link TM, Heindel W. Periosteal chondroma: MR characteristics. J Comput Assist Tomogr 2001;25:425-30.
Teh J, Whiteley G. MRI of soft tissue masses of the hand and wrist. Br J Radiol 2007;80:47-63.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]