cellular neurofibroma

A cellular neurofibroma, also known as an atypical neurofibroma, is a type of benign tumor that can appear on the skin or under it. According to search results [2], this type of neurofibroma displays features such as:

• Atypical, hyperchromatic, enlarged nuclei
• Diffuse hypercellularity

These characteristics should not be mistaken for malignancy, and are often used to identify cellular neurofibromas in medical contexts.

In terms of microscopic (histologic) description, a cellular neurofibroma may show a proliferation of all elements of peripheral nerves, including Schwann cells with wavy serpentine nuclei and pointed ends [3]. This can be seen in sections of the tumor, which represent a non-encapsulated lesion in the dermis.

It's worth noting that cellular neurofibromas are often associated with neurofibromatosis type 1 (NF1), a genetic disorder that predisposes individuals to develop benign tumors on their skin and other tissues [4]. However, these tumors should not be mistaken for malignancy, and their presence is an important diagnostic feature of NF1.

Overall, the description of a cellular neurofibroma highlights its unique histological features and association with NF1.

Diagnostic Tests for Cellular Neurofibromas

Cellular neurofibromas are benign tumors that arise from nerve tissue. Diagnosing these tumors can be a bit complex, but various tests can help confirm the presence and extent of the condition.

• Imaging Tests: Imaging studies such as Computed Tomography (CT) scans or Magnetic Resonance Imaging (MRI) can help identify cellular neurofibromas. These tests can provide detailed images of the tumor's size, location, and relationship to surrounding structures [2].
• Physical Examination: A thorough physical examination by a healthcare provider is essential in diagnosing neurofibromas. They may also use imaging tests like CT or MRI to confirm the diagnosis [3].
• Genetic Testing: While not always necessary, genetic testing can be used to confirm the presence of a mutation in the NF1 gene, which is associated with neurofibromatosis type 1 (NF1) [7].

It's worth noting that cellular neurofibromas are typically diagnosed based on clinical criteria and imaging studies. Molecular genetic testing may also be considered in certain cases.

References:

[2] Apr 12, 2022 - CT and MRI are first-line imaging studies when pheochromocytoma is suspected based on abnormal serum or urine screening tests. [3] Healthcare providers typically use a physical examination to diagnose neurofibromas. They might also use the following imaging tests: Computed tomography (CT) ... [7] by RE Ferner · 2007 · Cited by 1249 — NF1 mutational analysis clarifies the diagnosis in some uncertain cases and in individuals contemplating prenatal diagnosis (see section on prenatal diagnosis).

Differential Diagnosis of Cellular Neurofibroma

Cellular neurofibromas are a type of neurofibroma that show increased cellularity, often raising the differential diagnosis with Malignant Peripheral Nerve Sheath Tumor (MPNST) [1]. The main differential diagnoses for cellular neurofibromas include:

• Malignant Peripheral Nerve Sheath Tumor (MPNST): A aggressive neurogenic neoplasm arising from peripheral nerve or pre-existing nerve sheath tumor, including neurofibromas. Approximately 50% of cases are associated with Neurofibromatosis Type 1 (NF1) [11].
• Schwannoma: Shows Antoni A and B pattern and is encapsulated. Plexiform neurofibroma may resemble schwannoma.
• Plexiform Neurofibroma: May show moderate cellularity and a more complex architecture, often raising the differential diagnosis with MPNST.

Key Features to Distinguish Cellular Neurofibromas from Other Conditions

To distinguish cellular neurofibromas from other conditions, the following key features should be considered:

• Cellularity: Cellular neurofibromas show increased cellularity compared to classic neurofibromas.
• Architecture: Plexiform neurofibroma may show a more complex architecture and resemble schwannoma.
• Immunohistochemistry: Neurofibromas typically have axons coursing through the mass, which stain with neurofilament immunohistochemically.

References

[1] Some neurofibromas show unusual features such as degenerative cytological atypia (neurofibroma with ancient change, atypical neurofibroma) and/or increased cellularity (cellular neurofibroma)(Figure 2e,f), often raising the differential diagnosis with MPNST.

[11] Neurofibroma and cellular neurofibroma with atypia: a report of 14 tumors. Am J Surg Pathol. 1997