What is Glomus Cancer?
Glomangiomas, also known as glomuvenous malformations (GVM), are uncommon skin conditions where specific venous cells, known as glomus cells, along with the vein system show up when tested. These glomus cells are special cells similar to muscle cells and help control body temperature.
The first mention of glomangiomas and their in-depth study were done by a doctor named Masson and then further detailed by Papoff. There are three categories of these conditions, which are labeled according to the most abundant component in each case:
1. Solid: Mostly contains glomus cells.
2. Glomangioma: Mostly made up of blood vessels.
3. Glomangiomyoma: Majorly composed of smooth muscle cells.
These types of glomangiomyomas are then divided into three specific types as follows: regional (seen in specific areas), disseminated (spread throughout the body), and congenital plaque-like (present at birth).
Glomangiomas are typically present in large numbers, frequently appearing at birth or during childhood, and usually, they don’t spread to the subungual region (the area underneath the fingernails or toenails). Most glomangiomas are not harmful, but there have been cases where they were cancerous. The disseminated type, which spreads throughout the body, is not common.
What Causes Glomus Cancer?
Glomangiomas, which are a type of skin growth, can sometimes run in families or be passed down from parents. About 38% to 68% of glomangiomas are inherited. This inherited trait is often dominant, meaning that one copy of the altered gene in each cell is sufficient to cause the disorder. Despite this, the appearance and severity of the condition can vary. The abnormal gene, known as Glomulin, is located within a particular area of chromosome 1. Mutations, or changes, in this gene can cause the condition. In fact, 14 different mutations related to this condition have been identified in patients. These mutations can result in a decrease in the gene’s normal function, which ends up increasing the levels of certain proteins, cyclin E and c-Myc, in the body. In roughly 60% of cases, another family member also has the condition. This condition can appear at birth or may develop in adolescence.
There’s a type of inherited glomangioma called the ‘segmental type 2.’ It starts with one main growth, which is then followed by several smaller growths appearing on distant parts of the body.
There’s also another type, where glomangiomas occur due to spontaneous or new changes to the genes. This is called sporadic or de novo mutation and often appears at birth.
Risk Factors and Frequency for Glomus Cancer
Glomangiomas, a type of skin tumor, are relatively rare, accounting for 1.6% to 2.0% of all soft skin tumors and 20% of all glomus tumors. An even rarer type, called plaque-like glomangiomas, have been reported in just 4 cases. They are seen more often in males. Approximately one-third of all patients with glomangiomas are diagnosed before they turn 20. Around 10% of glomangiomas are of a kind known as disseminated.
The most common reason that people with vascular abnormalities are referred to a specialist is because they have venous malformations.
Signs and Symptoms of Glomus Cancer
Glomangiomas typically manifest as purple skin bumps at birth, appearing in a pattern similar to cobblestones. The skin bumps usually have a bluish-purple color and vary in both size (from 2 to 10mm) and quantity. These lesions can hurt when touched. Tenderness and pain are commonly triggered by pressure and cold. They are usually found in areas with a lot of glomus bodies, such as the ends of the limbs, particularly the palms, wrists, forearms, feet, and areas under the nail. Around 75% of the cases have these skin bumps on the hands.
It’s very rare, but these lesions can sometimes affect internal organs. Such instances have been reported in various body parts like the nasal cavity, areas around the heart, gastrointestinal tract, respiratory tract, urogenital tract, and the liver and gallbladder system. There have been instances of patients with Glomangiomas having heart abnormalities, such as ventricular septal defects and transposition of the great vessels.
There’s even a rare case where glomangiomas affected nerves, but generally, human nerves don’t contain glomus bodies. When the glomangiomas develop in the trachea, it might cause shortness of breath, coughing up blood, and discomfort or pain behind the breastbone.
Glomangiomas are bigger and not as sharply defined as solitary tumors. They tend to grow slowly over time. These skin lesions are sometimes accompanied by a specific set of symptoms known as the ‘classic triad’. This includes hypersensitivity, intermittent pain, and pinpoint pain. However, most of the time, they don’t come with these specific symptoms.
There’s also a type of glomangiomas called the ‘plaque-like’ type, which appears as hardened, bumpy, or discolored lesions. They don’t usually hurt, but they can bleed even with slight injuries. They’re also bigger than other types of glomangiomas, and they’re the least common type.
Testing for Glomus Cancer
The way we confirm a diagnosis is by looking at the tissue under a microscope, a process known as histopathology. Sometimes, a tumor might look unusual, and in this scenario, we use a technique called immunohistochemistry to help with the diagnosis. In these cases, we look for smoothelin, which tells us about the smooth muscle cell.
We also use a tool called an electron microscope to look at the cells in more detail. For this particular condition, we look for a specific type of cell called glomus cells, and the presence of dense bodies and smooth muscle strings within these cells can provide important information.
An X-ray might be performed to look for any bone defects. Additional tests such as MRIs and color Doppler ultrasounds can give us more information about the shape, size, and precise location of a tumor, if there is one. A specific type of MRI called dynamic time-resolved contrast-enhanced MR angiography gives us insight into the blood supply to the tumor, which can be critical for planning any treatment.
Treatment Options for Glomus Cancer
The aim of the treatment is to reduce the symptoms. For pain-free regions, it’s usually best to simply keep an eye on them and observe any changes. Various treatment methods are available including surgery, a type of radiation called electron-beam radiation, a technique called ‘sclerotherapy’ which involves using saline (salt solution) or a substance called sodium tetradecyl sulfate, as well as different types of laser treatments.
Lesions that cause pain are typically removed through a process called excision therapy. Sclerotherapy, the saline or sodium tetradecyl sulfate technique, has been found to be more effective for problems related to veins rather than glomuvenous malformations, which are specific clusters of veins and cells. For nasal cases, it’s usually recommended to do surgery or a minimally invasive procedure called endoscopic excision.
In certain cases where the glomangiomas, a type of benign blood vessel tumor, are large and hard to remove, a specific type of laser known as a 1064-nm Nd: YAG laser is effective. This laser has also produced positive results in symptomatic cases that run in families.
Interestingly, using external pressure from tight garments to compress the area has been found to actually increase the pain.
What else can Glomus Cancer be?
Glomus tumors are often mistaken for other conditions because of similarities in their appearances or symptoms. Doctors consider the following when diagnosing a glomus tumor:
- Venous malformations, such as glomangiomas that are limited to skin and mucosa. Other venous malformations can extend to deeper tissue layers like muscles.
- Schwannoma, which is a tumor of the tissue that covers nerves.
- Blue rubber bleb nevus syndrome (BRBNS), characterized by multiple soft and compressible skin and internal organ lesions. It is sporadic and could lead to gastrointestinal bleeding and death.
- Neuroma, a benign growth of nerve cells.
- Hemangiopericytoma, a rare type of soft tissue cancer.
- Angioleiomyoma, a benign tumor that originates from the smooth muscle cells of a vessel wall.
- Hamartoma, a non-cancerous growth seen in a variety of tissues.
- Hemangioma, benign tumors formed by a collection of excess blood vessels.
- Subdermal mass, which is any growth that appears under the skin.
- Carcinoid tumors, a type of slow-growing cancer that can arise in several places throughout your body.
- Paraganglioma, a rare growth of certain cells.
- Maffucci syndrome, where multiple vascular nodules appear subcutaneously on fingers and toes.
Glomus tumors are typically seen in adults. They often cause pain and commonly involve nail beds. The dominant cells in these tumors are called glomus cells. Other conditions resembling glomus tumors include Spiradenoma, Leiomyoma, and compressible painful Venous malformations.
What to expect with Glomus Cancer
If a glomangioma, a type of skin growth, is completely removed through surgery, the outlook is generally positive. However, if the glomangioma has spread to other parts of the body (a condition known as metastasis), the prognosis or likelihood of recovery is less positive.
Possible Complications When Diagnosed with Glomus Cancer
Recurrence or the reappearance of surgically removed lesions is observed in 10% to 33% of cases.
The chance of these lesions turning malignant or cancerous is very low. Risk factors for malignancy include:
- Size larger than 2 cm
- Deep lesions
- Invasion into muscle and bone
- High cell growth activity
Cases of lesions spreading to other parts of the body (metastasis) have been reported, but are exceedingly rare.
Lesions can also cause nerve compression.
These lesions can become life-threatening due to the risk of growth, bleeding, or blocking vital organs.
There has been a known case where a kind of mole commonly found in children, known as Spitz nevi, grew on an unusual vascular birthmark known as a congenital glomuvenous malformation. It’s believed that the increased blood supply in the birthmark can help nourish hair follicles. There’s also a possibility that a mutation in a protein called glomulin may play a part in this.
Preventing Glomus Cancer
If the patient observes any additional growth, experiences bleeding, or feels their condition is recurring, they should not hesitate to go back to their doctor immediately.
