CASE 99

By: Dr. Aliya Sarhan Al Barwani

HISTORY: 27-year-old male with pain in distal index finger.

What are the findings?

List three differential diagnosis?

FINDINGS:

Plain Radiograph: A small soft tissue mass along the ulnar aspect of distal phalanx of the index finger. It shows adjacent smooth cortical erosion and sclerotic rim (typical for a slow growing process).

MRI: The nodular mass is hypointense on T1WI and hyperintense on T2WI fat sat image.

DIFFERENTIAL DIAGNOSIS:

·        Glomus tumor.

·        Epidermal inclusion cyst.

·        Giant cell tumor of tendon sheath.

DIAGNOSIS:

Glomus tumor.

PEARLS AND DISCUSSION:

Glomus tumor is actually a hamartoma that arises from the glomus body, typically seen at the distal extremities. These lesions are most common in females in the third and fourth decades. Patients are present with painful small firm red-blue nodule under the finger nail.

The literature varies, with the prevalence of bone erosion estimated at 15-65%. On MR images, osseous involvement in glomus tumors results in smooth bony expansion, with plain films revealing a sclerotic rim typical for a slow growing process. Treatment is surgical excision. MRI can visualize the rare recurrence in affected individuals.

FURTHER READING:

1.      Karegowda LH1 and Shenoy.  Importance of radiological imaging in a case of subungual glomus tumour. BMJ Case Rep. (2014)

2.      Baek HJ and Lee SJ. Subungual tumors: clinicopathologic correlation with US and MR imaging findings. Radiographics. (2010)

3.      Horcajadas AB, Lafuente JL. Ultrasound and MR findings in tumor and tumor-like lesions of the fingers. Eur Radiol. (2003)