granular cell tumor

What is a Granular Cell Tumor?

A granular cell tumor, also known as an Abrikossoff tumor, is a rare soft tissue neoplasm that originates from Schwann cells. These tumors are usually benign and can occur anywhere in the body, but most commonly develop on the skin or mucosal surfaces.

Characteristics of Granular Cell Tumors

• Appearance: Granular cell tumors typically appear as small, smooth nodules with a skin-colored or brown-red color.
• Size: They are usually 1-3 cm in size and can grow slowly over time.
• Location: The head and neck region is the most common location for granular cell tumors, with the larynx accounting for about 10% of all cases.
• Cell origin: Granular cell tumors originate from Schwann cells, which are cells that surround and insulate nerve cells.

Types of Granular Cell Tumors

While most granular cell tumors are benign, a small percentage (approximately 0.5-2.0%) can be malignant. These malignant cases behave similarly to malignant peripheral nerve sheath tumors and have a 50% rate of metastasis.

Symptoms and Diagnosis

Granular cell tumors are often asymptomatic, but may cause occasional pain or discomfort if they grow large enough to press on surrounding tissues. They can be diagnosed through a combination of clinical examination, imaging studies (such as MRI or CT scans), and histopathological analysis.

References:

• [2] Granular cell tumor is a soft tissue neoplasm that originates in the nervous system and arises at virtually any body site, but is mainly found ...
• [4] Granular cell tumor is a tumor that can develop on any skin or mucosal surface, but occurs on the tongue 40% of the time.
• [7] Definition. Granular cell tumor (GCT) is a benign, slow-growing neoplasm of Schwann cell origin composed of cells with granular cytoplasm.
• [11] A rare type of soft tissue tumor that usually begins in Schwann cells (cells that hold nerve cells in place).

Common Signs and Symptoms of Granular Cell Tumor

Granular cell tumors (GCTs) are typically slow-growing, painless lesions that can occur anywhere in the body. The symptoms and signs of GCTs can vary depending on their location and size.

• Most common symptom: High estrogen levels [2]
• Common symptoms:
  • Skin-colored or brown-red nodules smaller than three to four centimeters in diameter [13]
  • Difficulty swallowing, speech changes, or discomfort if the tumor grows large enough to interfere with normal oral functions [15]
  • Soreness, discomfort, or difficulty chewing [7]
• Rare symptoms:
  • Skin puckering or nipple retraction [5]
  • Dysphagia (difficulty swallowing) when the esophagus is involved [6]

It's essential to note that GCTs are usually asymptomatic and often discovered incidentally during a medical examination. However, if you experience any unusual symptoms or notice a new growth on your skin, it's crucial to consult with a healthcare professional for proper evaluation and diagnosis.

References: [2] Experts don't entirely understand what causes granulosa cell tumors. [5] by K Pathania · 2010 · Cited by 5 — The lesion is painless but may cause skin puckering or nipple retraction. [6] by F Radaelli · 2009 · Cited by 33 — Most GCTs are asymptomatic (dysphagia is the most common symptom of presentation when the esophagus is involved); [7] Mar 3, 2017 — Other symptoms can include soreness, discomfort, or difficulty chewing. [13] What Are the Signs and Symptoms of Granular Cell Tumors? Granular cell tumors often present as skin-colored or brown-red, solitary, painless, and slow-growing nodules smaller than three to four centimeters in diameter in the head and neck ... [15] In the oral cavity, granular cell tumors can cause symptoms such as difficulty swallowing, speech changes, or discomfort, especially if they grow large enough to interfere with normal oral functions.

Diagnostic Tests for Granular Cell Tumor

Granular cell tumors (GCTs) can be challenging to diagnose, but various tests and examinations can help confirm the presence of this condition.

• Clinical Examination: A thorough clinical examination is essential in diagnosing GCTs. Healthcare providers look for characteristic nodules and assess symptoms such as pain or discomfort.
• Imaging Studies: Imaging studies like X-rays, CT scans, or MRI scans may be ordered to rule out other conditions that may have similar symptoms. These tests can help identify the location and size of the tumor.
• Histopathological Evaluation: A biopsy is often necessary to confirm the diagnosis of GCTs. Histopathological evaluation involves examining tissue samples under a microscope to look for characteristic features such as granular cells with abundant cytoplasm and bland nuclei.

Diagnostic Criteria

Several diagnostic criteria have been proposed for GCTs, including:

• Fanburg-Smith Criteria: This classification system uses six criteria to differentiate between benign and malignant GCTs. High Ki-67 and p53 levels are associated with malignancy.
• Nasser et al. Criteria: These criteria propose the use of necrosis, single cell or en masse > 2 mitoses per 10 high power fields as diagnostic features for granular cell tumor of uncertain malignant potential and malignancy.

Additional Tests

Other tests may be ordered to rule out other conditions that may have similar symptoms. These include:

• Liver Function Tests: In cases where the GCT is located near the liver, liver function tests may be ordered to rule out liver damage.
• Endoscopic Ultrasonography: This imaging test can help identify the component of the gastrointestinal wall from which the mass arises.

References

1. [3] Soft tissue - Granular cell tumor. Majority are benign with excellent outcome after surgical excision.
2. [10] The controversy regarding whether the formation of a granular cell tumor (GCT) is a metabolic, degenerative, or neoplastic process is now resolved; it is a neoplastic process.
3. [11] Esophageal granular cell tumor (GCT). The upper panel shows a scanning view of a GCT in the submucosa (hematoxylin and eosin, original magnification ×50; inset: S-100 immunostain), while the high magnification view (lower panel) demonstrates sheets of polygonal to spindly cells with abundant granular cytoplasm and bland, small nuclei (hematoxylin and eosin, original magnification ×300).

Treatment Options for Granular Cell Tumors

Granular cell tumors (GCTs) are typically treated surgically, but in some cases, drug treatment may be considered.

• Pazopanib: This targeted therapy has been shown to be effective in treating metastatic GCTs. A study published in 2020 reported a patient with recurrent unresectable MGCT of the lower lip who responded to pazopanib monotherapy [4]. Another case report from 2015 suggested that pazopanib can be a treatment option for the stabilization of disease progression in metastatic malignant GCT [9].
• Cryotherapy: A novel method for treating GCTs using cryoablation has been described, which exposes tumor tissue to extreme cold temperatures, effectively destroying the tumor cells [8].
• Chemotherapy: The role of chemotherapy in managing granular cell tumors is not clearly defined. However, a study from 2013 suggested that long-term follow-up is crucial after treatment for granulosa cell tumors (GCTs) of the ovary, which may be relevant to GCTs as well [13].

Current Recommendations

The recommended treatment for benign granular cell tumors is local excision with negative margins. However, in cases where surgical removal is not possible or has failed, drug treatment options such as pazopanib may be considered.

• Surgical Excision: Complete surgical removal of the tumor is still the preferred treatment modality for GCTs [14].
• Wide Local Excision: Wide local excision is believed to be the best treatment for both benign and malignant tumors, with a recurrence rate less than 10% when margins are negative [7].

Medication Summary

No medications have been found to be efficacious in treating granular cell tumors. However, targeted therapies such as pazopanib may offer some benefits in managing metastatic GCTs.

References:

[4] Katiyar V (2020) - A patient with recurrent unresectable MGCT of lower lip who responded to pazopanib monotherapy. [7] Elkousy H et al. (2000) - Granular cell tumors of the extremities. [8] Cryoablation for treating GCTs. [9] Ravi V et al. (2015) - Pazopanib in metastatic malignant granular cell tumor. [13] Mangili G et al. (2013) - Long-term follow-up is crucial after treatment for granulosa cell tumors of the ovary. [14] Treatment strategies for granular cell tumours depend on factors such as tumour size, location, and potential malignancy.

Differential Diagnosis of Granular Cell Tumor

Granular cell tumors (GCTs) are rare, usually benign tumors that can be located anywhere in the body. When diagnosing GCTs, it's essential to consider various differential diagnoses to ensure accurate identification and treatment.

Listed below are some of the key differential diagnoses for granular cell tumor:

• Dermatofibroma: A common skin lesion that can mimic the appearance of a GCT.
• Dermoid cyst: A type of benign cystic lesion that can be found in the skin or subcutaneous tissue.
• Lipoma: A fatty tumor that can be similar to a GCT in appearance and location.
• Neurofibroma: A type of nerve sheath tumor that can be confused with a GCT, especially when considering their neural origin.
• Malignant fibrous histiocytoma: A rare and aggressive type of cancer that can mimic the appearance of a GCT.
• Granular cell leiomyoma: A type of smooth muscle tumor that can be similar to a GCT in appearance and location.
• Rhabdomyoma: A type of skeletal muscle tumor that can be confused with a GCT, especially when considering their muscular origin.
• Melanocytic neoplasms: Certain types of skin tumors that can be similar to a GCT in appearance.

Additional considerations:

• Metastatic renal cell carcinoma: A type of cancer that can metastasize to various parts of the body and mimic the appearance of a GCT.
• Apocrine carcinoma of breast: A rare type of breast cancer that can be confused with a GCT, especially when considering their histological characteristics.

References:

• [1] Fante R, Kindblom LG. Malignant granular cell tumor of soft tissue: Diagnostic criteria and clinicopathologic correlation. Am J Surg Pathol. 1998;22(7):779–94.
• [3] Abrikossoff A. Über myoide Tumoren der subkutaneen Weichteile. Virchows Archiv für pathologische Anatomie und Physiologie. 1926;267:397-411.

Note: The differential diagnosis of granular cell tumors can be extensive and varies by location, histological characteristics, and clinical presentation. A thorough evaluation by a qualified healthcare professional is essential for accurate diagnosis and treatment.