A glomus tumor is a rare, typically benign growth originating from specialized cells. Though usually non-cancerous, they can cause significant discomfort due to their location. Accounting for less than 2% of all soft tissue tumors, these growths are often small and challenging to identify without medical evaluation.
Understanding Glomus Tumors
Glomus tumors develop from glomus cells, modified smooth muscle cells found within glomus bodies. These microscopic glomus bodies are part of the body’s neuromyoarterial apparatus, primarily functioning in thermoregulation by controlling blood flow to the skin. They regulate body temperature by shunting blood away from or toward the skin surface.
While glomus bodies are distributed throughout the dermis, they are most concentrated in the hands and feet. Consequently, glomus tumors most frequently occur in these distal extremities, often found beneath the fingernail (subungual), in the palm, or on the sole of the foot. These tumors are usually solitary and small, typically measuring less than one centimeter, though they can occasionally reach up to two centimeters.
Although less common, glomus tumors can also appear in other areas of the body, or even in deeper soft tissues and internal organs like the stomach, lungs, or bones. These growths are slow-growing. The vast majority of glomus tumors are benign, but in rare instances, they can exhibit malignant characteristics.
Recognizing the Signs
Glomus tumors cause intense and often disproportionate localized pain. This pain can be excruciating, particularly when the affected area is exposed to cold temperatures or direct pressure. Patients frequently report sensitivity to cold, where immersing the affected part in cold water can elicit severe pain.
Another common symptom is point tenderness, meaning the pain is highly localized to a specific, small area. For tumors beneath the fingernail, additional signs may include a bluish or reddish discoloration visible through the nail. The nail itself might also show changes such as elevation or deformity as the tumor grows underneath it.
Diagnosis and Identification
Diagnosing a glomus tumor begins with a thorough clinical examination. Several specific clinical tests can help indicate its presence. The “Love’s test” involves applying pinpoint pressure to the suspected area, which elicits exquisite localized pain.
Another diagnostic aid is “Hildreth’s test,” where a tourniquet is applied to the limb to reduce blood flow; if pain and tenderness decrease, it suggests a glomus tumor. Both Love’s and Hildreth’s tests demonstrate high sensitivity in identifying these tumors. Imaging techniques are also crucial for confirming the diagnosis and pinpointing the tumor’s location and size.
Magnetic Resonance Imaging (MRI) is considered the standard for diagnostic imaging due to its high resolution, capable of revealing the tumor’s presence and characteristics. Ultrasound and X-rays can also be used, with X-rays sometimes showing bone erosion in subungual tumors. While clinical and imaging findings strongly suggest a glomus tumor, a definitive diagnosis is confirmed through histopathological examination after surgical removal.
Treatment Approaches
The most effective treatment for a symptomatic glomus tumor is surgical excision. This procedure offers a high success rate in resolving the patient’s symptoms, particularly the severe pain associated with these growths. The goal of surgery is to remove the entire tumor capsule to ensure complete symptom relief and minimize the chance of recurrence.
For subungual tumors, this often involves removing the nail plate to access and excise the tumor from the nail bed. The recovery process following surgery varies depending on the tumor’s location, size, and depth. While surgical removal is curative, there is a possibility of recurrence, especially if any part of the tumor is not completely excised during the initial procedure.