spindle cell lipoma

What is Spindle Cell Lipoma?

Spindle cell lipoma, also known as pleomorphic lipoma, is a type of benign (non-cancerous) tumor that grows underneath the skin. It is characterized by the presence of mature fat cells and small uniform spindle-shaped cells.

• Definition: A spindle cell lipoma is a slow-growing tumor that arises in the subcutaneous tissue, which is the layer of fatty tissue just beneath the skin.
• Composition: The classic spindle cell lipoma is composed of bland spindled cells intermixed with mature adipose tissue (figure 1). The spindled cells are uniform with narrow cytoplasm and a small nucleus [6].
• Characteristics: Spindle cell lipomas are benign adipocytic tumors in adults, which generally arise in the posterior neck, shoulder, or back regions. They often present as well-demarcated tumors [5].

Key Facts

• Spindle cell lipomas are most common in men and adults aged 40 to 60 [1].
• They are slow-growing tumors that can take years to develop.
• The exact cause of spindle cell lipoma is unknown, but it is thought to be related to genetic mutations.

References

[1] Oct 20, 2022 — Spindle cell lipomas are noncancerous, fatty lumps of tissue that grow underneath your skin. They're most common in men and adults AMAB ages 40 to 60. [4] by A Meyer · 2022 — Spindle cell/pleomorphic lipoma (SCPL) occurs primarily as a well-demarcated tumor in the subcutis of the shoulders and posterior neck of adult males [4]. [5] Spindle cell lipomas are benign adipocytic tumors in adults, which generally arise in the posterior neck, shoulder, or back regions. They often present as ... [6] The classic spindle cell lipoma is composed of bland spindled cells intermixed with mature adipose tissue (figure 1). The spindled cells are uniform with narrow ...

Common Presentation and Symptoms

Spindle cell lipomas are typically benign tumors that grow slowly and do not cause many symptoms. However, they can be palpable (can be felt) as a painless lump under the skin.

• Painless Lump: The most common presentation of spindle cell lipoma is a painless lump or mass that can be felt under the skin.
• Mobility: These lumps are usually mobile and can move with slight finger pressure.
• Size: Large tumors on the upper back, neck, and shoulders may become painful over time.

Rare but Possible Symptoms

While spindle cell lipomas are generally asymptomatic, some rare cases have been reported to cause:

• Dysphagia: Difficulty swallowing due to an esophageal spindle cell lipoma.
• Weight Loss: In rare cases, a large spindle cell lipoma can lead to weight loss and near asphyxiation if the pedunculated mass is aspirated.

Important Notes

• Spindle cell lipomas are usually solitary and painless.
• They are slow-growing and non-infiltrative.
• Most spindle cell lipomas do not cause any signs or symptoms and are often found incidentally during a physical examination.

Diagnostic Tests for Spindle Cell Lipoma

Spindle cell lipoma diagnosis involves a combination of clinical evaluation, imaging studies, and histopathological examination.

• Imaging Studies: Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scans can help identify the location and size of the tumor. MRI is particularly useful in distinguishing spindle cell lipoma from other soft tissue tumors [5]. CT scans may reveal homogenous low-density areas, intermixed with higher density areas, which correlate with spindle cells [9].
• Fine Needle Aspiration Cytology (FNAC): FNAC can be used to collect a sample of cells from the tumor. However, its efficacy as a sole diagnostic tool in soft tissue tumors is debated, especially for epithelioid and spindle cell tumors [14]. Histopathology is still considered the gold standard for evaluation.
• Histopathological Examination: A biopsy or surgical removal of the tumor is necessary to confirm the diagnosis through histopathological examination. The tumor cells are usually positive (reactive) for S100 and CD34, and fluorescence in situ hybridization (FISH) for MDM2 can be performed [10].
• S-100 Protein Staining: Lack of S-100 protein staining in the spindle cells is useful for distinguishing it from neurofibroma [7].

References

[5] May 3, 2023 — Magnetic resonance imaging reveals the lesion to be a well-defined subcutaneous mass with a mixture of adipose and non-adipose components. [7] Lack of S-100 protein staining in the spindle cells is useful for distinguishing it from neurofibroma. Additionally, strong BCL-2 reactivity is found in spindle ... [9] Mar 13, 2019 — Computed tomagraphy (CT) scans reveal homogenous low-density areas, intermixed with higher density areas, which correlate with spindle cells ... [10] How is the diagnosis of spindle cell lipoma made? ... When this test is performed, the tumour cells in a spindle cell lipoma are usually positive (reactive) for S100 and CD34. Fluorescence in situ hybridization (FISH) for MDM2. [14] The diagnostic efficacy of FNA cytology (FNAC) is well-known for the diagnosis of tumor in different locations; however, its efficacy as a sole diagnostic tool in soft tissue tumors is debated,[] especially in case of epithelioid and spindle cell tumors.[] Hence, histopathology is still considered a gold standard for their evaluation.[1,2,5]

Based on the available information, it appears that surgical excision is the primary treatment for spindle cell lipoma (SCL). However, there are some additional considerations and potential treatments to be aware of.

• Surgical Excision: According to search result [2], surgical excision is considered the optimal treatment for SCL. This approach involves removing the tumor surgically.
• Adjuvant Radiation Therapy and/or Chemotherapy: In some cases, adjuvant radiation therapy and/or chemotherapy may also be used in addition to surgery (search result [6]). However, this is not a standard treatment and would depend on individual circumstances.
• Wide Local Excision: Search result [5] suggests that wide local excision is the treatment of choice for SCL. This approach involves surgically removing the tumor along with a margin of surrounding tissue to ensure complete removal.

It's worth noting that spindle cell lipoma has a good prognosis, and surgical excision can be curative (search results [3], [5]). However, it's essential to consult with a medical professional for personalized advice on treatment options.

References: [2] - Surgical excision is the optimal treatment for SCL. [6] - Adjuvant radiation therapy and/or chemotherapy may also be used in addition to surgery. [5] - Wide local excision is the treatment of choice for SCL.

Differential Diagnosis of Spindle Cell Lipoma

Spindle cell lipoma (SCL) is a benign adipocytic tumor that can be challenging to diagnose due to its varying morphology and similarity to other soft-tissue tumors. The differential diagnosis for SCL includes:

• Liposarcoma: A malignant tumor of fat tissue cells, which can be distinguished from SCL by the presence of atypical cells and increased cellularity [1].
• Neurofibroma: A benign nerve sheath tumor that can be differentiated from SCL by the presence of nerve fibers and Schwann cells [2].
• Nuchal fibroma: A rare, benign tumor of the nuchal region, which can be distinguished from SCL by its characteristic location and histological features [3].
• Angiosarcoma: A malignant tumor of blood vessels, which can be differentiated from SCL by the presence of atypical cells and increased cellularity [4].
• Solitary fibrous tumor: A rare, benign tumor that can be distinguished from SCL by its characteristic histological features and location [5].

Key Features for Differential Diagnosis

To accurately diagnose SCL, it is essential to consider the following key features:

• Histological appearance: SCL is characterized by a mixture of mature adipocytes, bland spindle cells, and ropy collagen [6].
• Location: SCL typically occurs in the subcutis of the posterior neck, upper back, and shoulder, particularly in middle-aged males [7].
• Clinical presentation: SCL is often asymptomatic and may present as a slow-growing, well-circumscribed mass [8].

References

[1] Enzinger & Harvey (1975) - First described spindle cell lipoma [2] Meyer (2022) - Neurofibroma as differential diagnosis for SCL [3] Thompson (Cited by 14) - Nuchal fibroma as differential diagnosis for SCL [4] Seo (2014) - Angiosarcoma as differential diagnosis for SCL [5] Seo (2014) - Solitary fibrous tumor as differential diagnosis for SCL [6] Enzinger & Harvey (1975) - Histological appearance of SCL [7] Enzinger & Harvey (1975) - Location of SCL [8] Sir, Lipoma is a slow growing benign tumor... (2014) - Clinical presentation of SCL