AtlasBenignOral Schwannoma

Benign Tumors

Oral Schwannoma

aka Neurilemmoma

Benign encapsulated tumour of Schwann cells arising from peripheral nerve sheath; solitary, slow-growing and eccentric to the parent nerve.

Cell
Schwann cell
Marker
S-100+
Rx
Excision

§ overviewOverview

Benign, encapsulated peripheral nerve sheath tumour composed exclusively of well-differentiated Schwann cells.

§ icdICD Classification

D36.1

§ epidemiologyEpidemiology

Tongue is the most common oral site; 25–55% of head-and-neck schwannomas are in the oral cavity; adults 20–50 y.

§ clinicalClinical Features

  • 01Slow-growing, painless, firm, submucosal nodule
  • 02Usually solitary
  • 03May cause paraesthesia if involving lingual/IAN

§ differentialDifferential Diagnosis

  • 01Neurofibroma
  • 02Fibroma
  • 03Lipoma
  • 04Salivary gland tumour

§ histopathHistopathology

  • 01Encapsulated tumour with Antoni A (compact spindle cells, Verocay bodies) and Antoni B (loose myxoid) areas
  • 02Verocay body: nuclear palisading around anuclear zones

§ investigationsInvestigations

  • 01MRI: 'target sign' (central low, peripheral high T2)
  • 02Fine-needle aspiration unreliable

§ ihcIHC / Special Stains

  • 01Strong diffuse S-100 positivity

§ treatmentTreatment

  • 01Complete surgical excision with preservation of parent nerve fascicles
  • 02Malignant transformation extremely rare

§ complicationsComplications

  • 01Nerve injury if excision incomplete
  • 02Rare recurrence

§ prognosisPrognosis

Excellent; malignant peripheral nerve sheath tumour only in NF1 setting.

§ examKey Examination Points

  • 01Solitary tongue nodule → biopsy
  • 02MRI target sign

§ revisionQuick Revision Summary

  • 01Antoni A/B · Verocay bodies · S-100+ · excision curative

§ vivaBDS Viva Questions

  • 01Antoni A vs B?
  • 02Schwannoma vs neurofibroma?
  • 03Malignant risk?

§ mcqsMCQs — Assessment (3)

Question 1

Most common oral site:

Question 2

Verocay bodies are found in:

Question 3

IHC marker:

References

  1. Neville BW. Oral & Maxillofacial Pathology, 4e

Draft — pending faculty review. Educational use only; verify against current guidelines and primary sources before clinical application.