Glomus tumor: revitalizing concepts

A female, caucasian, 22-year-old patient with no comorbidity, complaining of incapacitating crises of subungual pain in her left hallux, strong enough to wake her up in the middle of the night, starting four years ago, with progressive worsening. The symptom was triggered by a physical stimulus such as cold temperature , local pressure, and even wind causing the crises which improved as she immersed her feet into tepid water. The patient had already sought medical assistance several times, receiving multiple , different treatments, including treatment for mycosis, ten-dinitis and neuritis. Amongst the prescribed pharmaceuticals, she reported the use of analgesic, nonsteroidal anti-inflammatory and corticosteroid drugs, all of them with no response. Both plain radiography and ultrasonography of the first digit of her left foot did not characterize any pathological finding. Magnetic resonance imaging of her left hallux demonstrated the presence of a subungual solid, well-delimited nodule with hyposignal and homogeneous contrast uptake at T1-weighted-image (Figure 1). Such findings suggested the diagnosis of a glomus tumor , confirmed by histopathological analysis of surgical specimen following the surgical removal of the lesion (Figure 2). Complete symptoms resolution was observed after the surgical intervention. Glomus bodies are arterio-venous shunts present in several parts of the body, with greater concentration in the reticular layer of the dermis, especially located in the digits, palms of the hand and sole of the feet (1). Such structures are responsible for ther-moregulation by means of skin blood flow control, being constituted by an afferent arteriole, an anastomotic vessel named Soucquet-Hoyer canal involved by smooth muscle fibers, an af-ferent vein, nervous fibers and a peripheral capsule (1,2). Glomus tumors are rare benign lesions characterized by hamartomatous proliferation originating from glomus bodies. Such tumors correspond to 2% of all primary soft part tumors and to 1%-5% of all soft part tumors in the hand (1,3). Approximately 75% of glomus tumors occur in the hand, and 60% of them are subungual (a typical location of such tumors) (1,4). Glomus tumors were first described by William Wood in 1812, as a painful, sub-cutaneous, slow-growing tumor susceptible to temperature variations. Only later, in 1901, Grosser described the lesion as arterio-venous anastomoses, associating them with the body temperature regulation (2). Glomus tumors affect young adult individuals, particularly between their fourth and fifth decade of life, being seven times more frequent in women (5) , at a mean age of 39 (6). Clinically, Figure 2. …