CASE 46
By: Dr. Mai Mattar, MD and Dr. Nizar Al-Nakshabandi MD, FRCPC
HISTORY: 60-year-old female with ring finger pain and sensitivity to cold.
What are your findings?
What is the differential diagnosis?
What are the causes?
FINDINGS:
Plain Radiography: Scalloping of the radial and palmar aspect of the distal phalanx of the ring finger, with no destruction, suggesting that the findings are long-standing and non-aggressive.
On Ultrasound: Well-defined, ovoid, soft-tissue lesion at the palmar aspect of the tip of the distal phalanx.
MRI: Axial T1, T2FS and post contrast images: A well-defined lesion that is iso-intense to the nail bed on T1, bright on the T2FS images with intense post-contrast enhancement.
DIFFERENTIAL DIAGNOSIS:
Glomus tumor.
Epidermal inclusion cyst.
Subungual exostosis.
Soft tissue chondroma.
DIAGNOSIS:
Glomus tumor.
PEARLS AND DISCUSSION:
Glomus tumors are benign tumors (hamartomas) of the glomus body.
Up to 75% occur in the hand, 65% of these are in the fingertips, particularly in the subungual space.
They occur between 30 and 50 years of age with equal gender prevalence.
Clinical presentation: excruciating pain, intense tenderness that may be provoked by mild trauma, and temperature sensitivity. The nail may be ridged and discolored.
The lesions are well-circumscribed and usually smaller than 2 cm.
Treatment is by surgical excision.
Best diagnostic clue: Well-defined lesion within the subungual region with bone scalloping.
FURTHER READING:
Hye Jin Baek, Sun Joo Lee, Kil Ho Cho, Hye Jung Choo, Sung Moon Lee, Young Hwan Lee, Kyung Jin Suh, Tae Yong Moon, Jang Gyu Cha, Jae Hyuck Yi, Myung Hee Kim, Soo-Jin Jung, and Joon Hyuk Choi. Subungual Tumors: Clinicopathologic Correlation with US and MR Imaging Findings. RadioGraphics 2010 30:6, 1621-1636
