Tumors of the Ear and Temporal Bone

Ear Tumors 101 - Benign Beginnings

• Classification by Nature & Site:
  • Nature: Benign (non-cancerous), Malignant (cancerous).
  • Site: External Ear, Middle Ear, Inner Ear, Temporal Bone.
• Common Benign Tumors & Features:
  • Exostosis (Surfer's Ear):
    • Multiple, bilateral bony growths in External Auditory Canal (EAC).
    • Linked to cold water exposure.
  • Osteoma:
    • Solitary, unilateral, pedunculated bony tumor in EAC.
    • Often at bony-cartilaginous junction.
  • Ceruminous Adenoma/Pleomorphic Adenoma:
    • From ceruminous glands in outer EAC; slow-growing.
• General Benign Tumor Traits:
  • Slow growth, well-circumscribed.
  • Non-invasive locally.

⭐ Exostoses are typically bilateral and multiple, often linked to cold water exposure.

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Glomus Goodness - Vascular Vibes

• Origin: Paraganglionic cells (neural crest).
• Types:
  • Glomus Tympanicum: Arises from Jacobson's nerve on cochlear promontory.
  • Glomus Jugulare: Arises from jugular foramen (CN IX, X, XI involvement).
• Symptoms: Pulsatile tinnitus, conductive hearing loss (CHL).
  • 📌 Signs:
    • Brown's sign: Blanching of reddish mass behind TM on pneumatic otoscopy.
    • Phelps' sign (HRCT): Absence of bone between carotid canal & jugular fossa.
    • Aquino's sign: Blanching of tumor with carotid compression.

⭐ Glomus tympanicum typically presents as a reddish-blue mass behind an intact tympanic membrane.

• Fisch Classification (Glomus Jugulare):
  • Type A: Middle ear. B: Tympanomastoid. C: Infralabyrinthine, extending to petrous apex. D: Intracranial extension.
• Diagnosis:
  • HRCT: Bone erosion ('moth-eaten' appearance).
  • MRI + Gadolinium: 'Salt & pepper' appearance (flow voids & hemorrhage).
  • Angiography: Defines vascular supply.
• Management: Surgery (pre-op embolization), Radiotherapy (Gamma Knife).

Malignant Mayhem - Canal Invaders

• Squamous Cell Carcinoma (SCC): Most common (>80% temporal bone malignancies).
  • Locations: External Auditory Canal (EAC), Pinna, Middle Ear.
  • Risk Factors: Chronic Suppurative Otitis Media (CSOM), chronic otitis externa, radiation, HPV.
• Other Malignancies:
  • Basal Cell Carcinoma (BCC): Pinna primarily.
  • Adenoid Cystic Carcinoma: Perineural spread common.
  • Rhabdomyosarcoma: Most common ear sarcoma in children.
• Clinical Features:
  • Persistent, severe otalgia (out of proportion).
  • Chronic, blood-stained otorrhoea.
  • Hearing loss.
  • Facial palsy (poor prognostic sign).
  • Granulation tissue in EAC.
• Staging: University of Pittsburgh Staging System (T1-T4 for SCC).

⭐ Facial nerve palsy in the context of chronic ear discharge and pain is highly suggestive of malignancy until proven otherwise.

Tumor Tactics - Dx & Tx Plan

• Diagnosis (Dx):

  • History & Clinical Exam (Otoscopy, Cranial Nerves)
  • Audiometry: Type & degree of hearing loss
  • Imaging:
    • HRCT Temporal Bone: Bony erosion, extent
    • MRI: Soft tissue, perineural/intracranial spread
    • PET-CT: Staging/metastasis
  • Biopsy: Histological Dx (incisional/excisional)

    ⭐ Biopsy is mandatory for any suspicious lesion in the external auditory canal or middle ear to rule out malignancy.

• Treatment (Tx) Plan:

  • Benign: Observation (e.g., small exostoses) or Surgical excision if symptomatic.
  • Malignant: Multimodal approach (MDT essential: ENT, NeuroSx, Onco[Rad/Med])
    • Surgery: Sleeve resection, Lateral Temporal Bone Resection (LTBR), Subtotal Temporal Bone Resection (STBR), Radical Temporal Bone Resection (RTBR) (stage-dependent)
    • Radiotherapy (RT): Adjuvant/Primary
    • Chemotherapy (CT): Palliative, Neoadjuvant, Concurrent with RT

High‑Yield Points - ⚡ Biggest Takeaways

• SCC is the most common malignancy of the EAC and temporal bone.
• Glomus tumors are most common in the middle ear, causing pulsatile tinnitus & Brown's sign.
• Vestibular schwannoma: Most common CPA tumor; presents with unilateral SNHL.
• Osteoma: Most common benign tumor of the EAC.
• Progressive facial palsy with an ear mass suggests malignancy or facial nerve neuroma.
• Rhabdomyosarcoma: Most common childhood middle ear malignancy.