Mateusz Gładysz FESSH prep

FESSH prep Hand tumours Relative frequency of schwannoma and neurofibroma, recurrence after excision, internal plexiform neurofibroma and malignant peripheral nerve sheath tumour in neurofibromatosis type 1, Tinel sign, fascicular involvement and enucleation

Schwannoma and neurofibroma

Last reviewed v1.0

FESSH-086Hand tumours●○○ basic

Regarding benign peripheral nerve sheath tumours (schwannoma and neurofibroma):

  1. 1.Schwannomas outnumber neurofibromas among surgically excised benign peripheral nerve sheath tumours.

  2. 2.After excision, neurofibromas recur less often than schwannomas.

  3. 3.In neurofibromatosis type 1, internal plexiform neurofibromas are strongly associated with malignant peripheral nerve sheath tumour.

  4. 4.A positive Tinel sign over the mass is a typical clinical feature of a schwannoma.

  5. 5.Excision of an upper-limb schwannoma may require resection of nerve fascicles that cannot be separated from the tumour.

FESSH marking: +1 per correct statement, 0 for blank, −1 for incorrect. Click the same TRUE/FALSE button twice to clear it.

Question ID
FESSH-086
First published
Last reviewed
Version
v1.0
Answer key and explanations — open after answering

  1. 1. Schwannomas outnumber neurofibromas among surgically excised benign peripheral nerve sheath tumours.

    True

    In a series of 228 patients who had a benign peripheral nerve sheath tumour excised, schwannomas made up 76.3% and neurofibromas 22.4%; the series covered all body sites, and the upper (45.2%) and lower extremities were the commonest. Adani and colleagues likewise describe schwannomas as the most common benign tumours arising in peripheral nerves.

    • Raasveld FV, Hanna T, Pacheco FJ, Johnston BR, Valerio IL, Eberlin KR. Benign Peripheral Nerve Sheath Tumors: Recurrence Rates and Pain Outcomes Following Excision. Plast Reconstr Surg. 2026. PMID 41874286
    • Adani R, Tarallo L, Mugnai R, Colopi S. Schwannomas of the upper extremity: analysis of 34 cases. Acta Neurochir (Wien). 2014;156(12):2325-30. PMID 25223747

  2. 2. After excision, neurofibromas recur less often than schwannomas.

    False

    In the same series of 228 patients, the overall recurrence rate was 7.0%, and neurofibromas recurred more often than schwannomas (15.7% against 4.6%). Recurrence was also more frequent in patients with neurofibromatosis type 1 (NF1). Median follow-up was short, about one year.

    • Raasveld FV, Hanna T, Pacheco FJ, Johnston BR, Valerio IL, Eberlin KR. Benign Peripheral Nerve Sheath Tumors: Recurrence Rates and Pain Outcomes Following Excision. Plast Reconstr Surg. 2026. PMID 41874286

  3. 3. In neurofibromatosis type 1, internal plexiform neurofibromas are strongly associated with malignant peripheral nerve sheath tumour.

    True

    In 476 probands with neurofibromatosis type 1 (NF1), people with internal plexiform neurofibromas were 20 times more likely to have a malignant peripheral nerve sheath tumour (MPNST) than those without, and this was the only association that remained significant in the combined analysis. The authors note that clinical evidence suggests most MPNSTs in NF1 arise from pre-existing plexiform neurofibromas, and they recommend closer surveillance of patients with these tumours.

    • Tucker T, Wolkenstein P, Revuz J, Zeller J, Friedman JM. Association between benign and malignant peripheral nerve sheath tumors in NF1. Neurology. 2005;65(2):205-11. PMID 16043787

  4. 4. A positive Tinel sign over the mass is a typical clinical feature of a schwannoma.

    True

    In their series of 34 upper-limb schwannomas, Adani and colleagues advise looking for the typical signs of a schwannoma when assessing a palpable mass, such as a positive Tinel sign and peripheral paraesthesia. They note that magnetic resonance imaging and ultrasound show which nerve the tumour arises from.

    • Adani R, Tarallo L, Mugnai R, Colopi S. Schwannomas of the upper extremity: analysis of 34 cases. Acta Neurochir (Wien). 2014;156(12):2325-30. PMID 25223747

  5. 5. Excision of an upper-limb schwannoma may require resection of nerve fascicles that cannot be separated from the tumour.

    True

    Microsurgical dissection aims to preserve nerve fascicles, but some upper-limb schwannomas have fascicles that cannot be separated from the tumour. Resection may therefore involve these fascicles; use of a microscope does not guarantee complete fascicle preservation.

    • Adani R, Tarallo L, Mugnai R, Colopi S. Schwannomas of the upper extremity: analysis of 34 cases. Acta Neurochir (Wien). 2014;156(12):2325-30. PMID 25223747
    • Akambi Sanoussi K, Dubert T. [Schwannomas of the peripheral nerve in the hand and the upper limb: Analysis of 14 cases]. Chirurgie de la main. 2006;25(3-4):131-5. PMID 17175798
    • Sá Â, Azevedo LN, Cunha L. [Schwannoma of the Upper Extremity: Retrospective Analysis of 17 Cases]. Acta medica portuguesa. 2016;29(9):519-524. PMID 28060689