A 39-year-old female patient was referred with a slowly growing soft tissue mass at the right hand, the mass was located at the palmar site of proximal phalanx of the fourth finger.
A 39-year-old female patient was referred to our hospital with a slowly growing soft tissue mass at the left hand over a period of approximately 18 months, the mass was located at the palmar site of proximal phalanx of the fourth finger , and it was well circumscribed with lobulations and easily movable over the neighboring bone on physical examination. MRI study of the right hand was performed on a 1.5 T MR scanner, with SE T1, FSE T2, GRE T2, and post-gadolinium SE T1 sequences in three planes.
The localized form of a giant-cell tumor of the tendon sheath is uncommon. Giant cell tumor of the tendon (GCTT), also called extraarticular pigmented villonodular sinovitis of the tendon, presents as an extraarticular soft tissue swelling. This highly cellular lesion has a fibrous capsule which also separates the lobules, seen on microscopic and histopathological examination. Cytologic findings on smears obtained by fine-needle aspiration are rather characteristic and include a mixture of oval or polygonal mononuclear cells showing vacuolation and/or pigment deposition along with a population of multinucleated giant cells. The most common location of GCTT is the soft tissue of the hand, however it may be seen occasionally in the lower extremities, even in the spine. Gross morphology consists of a well delineated, lobulated mass lesion, tumor lobules reaching a diameter of several cm. The most characteristic feature is its location along the tendon sheath. The adjacent joint is not involved. The lesion has a low to intermediate signal intensity on T1- and T2- weighted SE images due to the paramagnetic effect of hemosiderin deposition in xanthoma cells and abundant collagenous proliferation. On GRE T2-weighted images signal intensity is increased. After IV injection of Gadolinium, GCTT usually exhibits a strong contrast enhancement which is due to the presence of numerous capillaries in the collagenous stroma.
Giant cell tumor of the tendon sheath of the hand
1. Location: The lesion is situated in the palmar tendon sheath region of the proximal phalanx of the 4th finger on the right hand, appearing as a localized soft tissue mass.
2. Morphology: The lesion has relatively well-defined margins, presenting a rounded or lobulated shape with a fibrous capsule, and is clearly demarcated from surrounding structures.
3. Signal/Density Characteristics:
• On T1WI, the lesion demonstrates relatively low to intermediate signal intensity;
• On T2WI, it also appears as low to intermediate signal, possibly related to hemosiderin deposition and abundant collagen within the tumor;
• On GRE T2WI (gradient echo sequence), relatively bright high-signal areas are often visible;
• Notable enhancement after contrast administration, suggesting rich blood supply.
4. Adjacent Tissues: The lesion is located around the tendon/tendon sheath, with no obvious bony erosion or destruction, and the joint is not involved.
Based on the above MRI characteristics and clinical history, the following differential diagnoses are considered:
1. Giant Cell Tumor of the Tendon Sheath (GCTT):
• Commonly found in the tendon sheath region of the fingers or dorsal hand, presenting as a locally slow-growing solid mass;
• Imaging typically shows low to intermediate signal intensity (on T1 and T2) with marked enhancement, often featuring hemosiderin deposits;
• Clinically and pathologically closely related to the tendon sheath, consistent with the features of this case.
2. Ganglion Cyst:
• Although frequently seen near joints or tendon sheaths, these are usually cystic lesions, appearing high signal on T2WI, with mild or no internal enhancement;
• The marked enhancement seen in this case does not strongly support a ganglion cyst.
3. Lipoma:
• On MRI, lipomas show high signal on both T1 and T2, and are suppressed on fat-saturation sequences;
• The pronounced enhancement and hemosiderin content observed in this lesion do not match the typical characteristics of a lipoma.
Considering the patient’s age, the slow growth observed clinically, and the typical MRI signal characteristics, the most likely diagnosis is:
Giant Cell Tumor of the Tendon Sheath (GCTT).
If uncertainty remains, a biopsy or postoperative histopathological examination is recommended for definitive confirmation.
1. Treatment Strategy:
• Surgical Excision: For lesions confirmed or highly suspected to be GCTT, complete resection is the primary treatment. Care should be taken to protect key neurovascular structures;
• Follow-up and Recurrence Monitoring: Postoperative regular imaging follow-up is necessary to monitor for possible local recurrence.
2. Rehabilitation and Exercise Prescription (FITT-VP Principle):
(1) Early Postoperative Period:
• Frequency: 2–3 times a day of gentle joint exercises to prevent finger stiffness;
• Intensity: Low intensity; avoid significant pain or swelling;
• Time: 5–10 minutes each session, adjusted according to pain and swelling;
• Type: Active or passive range-of-motion exercises, such as making a fist or finger flexion-extension;
• Progression: Gradually restore basic joint mobility before increasing exercise frequency and difficulty. Strengthening exercises such as grasping can be added as healing permits.
(2) Mid to Late Rehabilitation:
• Frequency: ≥3 times per week, with rest days in between to allow tendon sheath recovery;
• Intensity: Moderate intensity exercises using grip balls or elastic bands, closely monitoring pain and swelling;
• Time: 15–20 minutes per session, divided into sets with rest intervals to avoid fatigue-related injuries;
• Type: In addition to continuous range-of-motion training, incorporate hand muscle and gripping exercises, such as pinch strength and towel wringing;
• Progression: Gradually increase resistance and complexity of movements depending on soft tissue healing.
(3) Special Considerations:
• If redness or worsening pain occurs, reduce exercise intensity or temporarily stop and consult a physician or rehabilitation therapist;
• For patients with significant joint motion limitations, additional physical therapies (e.g., ultrasound therapy, warm compresses) may be employed to facilitate soft tissue relaxation and improve circulation.
Disclaimer:
This report is a reference analysis based on the available imaging and clinical information and does not replace an in-person consultation or professional medical advice. Patients should follow their specialist’s detailed guidance for treatment and rehabilitation, which is based on their specific clinical condition.
Giant cell tumor of the tendon sheath of the hand
