Abstract
Glomus tumors are benign lesions similar in structure to a normal glomus body with thermoregulatory action. These are mostly found in extremities with 75% in the hand and rarely in the foot. Though presence of glomus tumors in the foot is documented in literature, most have been in the medial three toes. In our study, though one was in the second toe, one was found in the fourth toe, which is even rarer. This report describes two female patients in their second decade of life who presented with gradually progressive painful swelling over the fourth toe since 10 years and second toe with associated nail deformation since 2 years, respectively. Clinically both revealed point tenderness over the swelling and cold intolerance relieved on taking non-steroidal anti-inflammatories(NSAIDs). Love test and Hildreth test were positive. Radiographs revealed no intralesional mineralization or osseous erosion. MRI revealed hypointense mass on T1 with hyperintensity on T2/STIR imaging. Clinically and radiologically the diagnosis of glomus tumor was confirmed. En masse excision was performed in both and histopathological examination confirmed the diagnosis. Patients were pain free on subsequent follow-ups. Glomus tumors of the foot are often misdiagnosed and need high clinical suspicion to avoid high morbidity associated with it.
Introduction
Glomus bodies are thermoregulatory cells functioning as special modified myoarterial structures in the deep dermis and play a key role in temperature and blood flow regulation. Glomus tumors are a group of benign lesions histologically similar in structure to a normal glomus body, originally described by Wood in 1812 as a “painful subcutaneous tubercle”. There are three subtypes of glomus tumors: glomangioma (prominent vessels), glomangiomyoma (prominent vasculature and smooth muscles) and malignant glomus tumors (marked nuclear atypia or abnormal mitotic figures). Representing less than 2 % of all soft tissue tumors, these lesions can be solitary or multiple and are most commonly located in extremities, particularly in the hand, which accounts for nearly 75 % of reported cases. In the largest published series of extradigital glomus tumors accumulated over 20 years at the Mayo clinic, only 2 out of 56 tumors were located in the foot. Foot glomus tumors are rare due to lower concentration of glomus bodies in foot even in the subungual region of toes. Delayed diagnosis is frequent due to lower incidence of glomus tumors in the foot and due to variable presentation. A glomus tumor most commonly presents as a solitary blue/purple nodular lesion with a classical triad of pain, point tenderness and temperature sensitivity. Clinical examination includes Hildreth test (91 % specificity and 92 % sensitivity) and Love test(100 % Sensitivity, 78 % specificity). Eliciting exquisite localized pain on application of direct pressure with pin head is considered a positive Love test. A reduction in pain on transient induction of ischemia using tourniquet with sudden return of pain on releasing tourniquet is a positive Hildreth test. Imaging that can assist diagnosis include plain x-ray, which may highlight scalloping of cortical bone of the distal phalanx in subungual tumors and Doppler ultrasonography indicative of a hypoechoic tumor. Magnetic resonance imaging shows well defined mass hypoechoic on T1 weighted image and hyperechoic on T2 weighted images. Differential diagnosis include ganglion cyst, myxoid cyst, epidermoid cyst, angioma, melanoma, leiomyoma, venous malformation, foreign body, melanoma, neuroma, blue nevi, Maffucci syndrome. Excision of the mass remains the mainstay of treatment in symptomatic patients. Histopathological examination of excised tumors is necessary for definitive diagnosis despite the advances in imaging modalities and resemblance with glomus cells.
Case details
Two female patients in second decade of life presented with painful swelling around toe nail of foot for ten and two years respectively. Details have been mentioned in the table below
| CASE 1( Fig. 1 ) | CASE 2( Fig. 3 ) | |
|---|---|---|
| Patient profile | 28year/female | 20year/female |
| Site | subungual region | subungual region |
| Toe involved | Right foot 4th toe | Left foot 2nd toe |
| Solitary/multiple | Solitary | Multiple |
| Associated nail deformation | Nil | Overlying nail deformity |
| Duration of symptoms | 10 years | 2 years |
| Gross dimension | 0.2 cm X 0.2 cm | 0.4 cm X 0.4 cm with a satellite lesion 0.3 cm X 0.2 cm |
| Management | excisional biopsy under spinal anaesthesia ( Fig. 1 ) | Excisional biopsy and en masse removal of mass with its satellite lesion under ring block with nail bed reconstruction ( Fig. 3 ) |
| Histopathology | well circumscribed tumor composed of small uniform round to oval cells with centrally located punched out nuclei, myxoid stroma and thin blood vessels around tumor nests cells with no evidence of malignancy suggestive of glomus tumor.( Fig. 2 ) | well circumscribed tumor composed of glomus cells, prominent vasculature with thick wall and fibromyxoid stroma. No signs of atypia or malignancy noted suggestive of glomangioma.( Fig. 4 ) |
| Recurrence | Nil | Nil |
CASE 1
( Figs. 1 and 2 )
