Age / Sex : 54 / F

Age / Sex : 54/F

Chief complaint : palpable mass in the right 1^st web foot dorsum area.
                          (Onset: 3 months ago)

giant cell tumor of tendon sheath

Discussion

Findings:
MR : There is a intermediate signal intensity lobulated contoured, well demarcated mass in the 2^nd phalanx extensor digitorum tendon on the T1-weighted images.  The mass is shown as intermediate signal on the T2 –weighted images. The mass shows moderate well enhancement on the post-contrast enhancement fat suppression T1-weighed MR images.

Diagnosis: Giant Cell Tumor of tendon sheath

Discussion:

Definition: Non-neoplastic benign tumor of giant cells in vicinity of joints, most commonly the hand, closely related to pigmented villonodular synovitis

Abbreviations and synonyms : Extraarticular pigmented villonodular synovitis, GCTTS, histiocytoma, benign synovioma

Imaging findings

Best diagnostic clue: intermediate signal intensity soft tissue mass on T1 & T2WIs

Two-thirds of masses located volar aspect of fingers-index and long finger most common

Morphology: Well-circumscribed fibrous mass

Fibrous septations-hypointense

Sharply defined interface without reactive edema of adjacent subcutaneous tissue

Pathology

 Accepted theory-reactive or regenerative hyperplasia

 2^nd most common mass on hand behind ganglion

 High rate of recurrence

 Firm, well-circumscribed lobulated mass

Clinical Issues

 Most common signs/symptoms: Painless slow growing mass present for weeks to years

May cause limited function of digit due to size of lesion

Osseous erosions related to lesion hypervascularity

References:

1.       Stoller DW, Tirman PFJ, Bredella MA. Diagnostic imaging Orthopaedics. A medial reference publishing company. 2004, 3-90 to 3-93.