Treatment of Tumors Involving the Ear Drum (Tympanic Membrane)
The treatment for tumors involving the tympanic membrane requires complete surgical excision with appropriate approach based on tumor type, size, and location, with consideration for hearing preservation when possible.
Types of Tumors Affecting the Tympanic Membrane
Tumors involving the tympanic membrane can be classified as:
Benign tumors:
Malignant tumors:
- Squamous cell carcinoma (most common) 3
- Basal cell carcinoma
- Mucoepidermoid carcinoma
- Myoepithelial carcinoma
- Melanoma
- Rhabdomyosarcoma
Diagnostic Approach
- Otoscopic examination: Bluish-red masses may be visible behind an intact tympanic membrane 4
- Imaging: CT and MRI are essential for accurate diagnosis and treatment planning
- Biopsy: Required for histopathological confirmation
Treatment Algorithm Based on Tumor Type
1. Benign Tumors
A. Glomus Tympanicum Tumors
- Type A (limited to promontory): Transcanal approach or retroauricular-transcanal approach 1
- Type B (completely filling middle ear):
- Smaller tumors: Transmastoid approach
- Larger tumors: Subtotal petrosectomy with blind sac closure of external auditory canal and middle ear obliteration 1
B. Fibromas of Tympanic Membrane
- Treatment: Total resection of the affected portion of tympanic membrane 2
- Outcome: Good prognosis with normal hearing restoration possible after complete excision
2. Malignant Tumors
A. Early Stage (T1-T2)
- Primary treatment: Complete surgical resection 3, 5
- Approach options:
- Wide local excision for superficial lesions
- Lateral temporal bone resection for deeper involvement
B. Advanced Stage (T3-T4)
- Primary treatment: More extensive surgery 3
- Lateral temporal bone resection with neck dissection when indicated
- Reconstruction with flaps (e.g., PMMC flap) as needed
- Adjuvant therapy: Postoperative radiotherapy and/or chemotherapy for high-risk features 3
3. Vestibular Schwannomas (if involving tympanic membrane)
- Small tumors without significant symptoms: Conservative surveillance, especially in older patients 6
- Growing tumors or symptomatic cases:
- Surgical options:
- Stereotactic radiosurgery: For tumors <3 cm without significant mass effect 6
Special Considerations
Hearing Preservation
- Attempt hearing preservation when possible, especially for benign lesions
- Hearing outcomes should be discussed with patients preoperatively
- Hearing aids may be necessary following treatment 6
Facial Nerve Function
- Intraoperative facial nerve monitoring is mandatory for middle ear and temporal bone surgeries 6
- Risk of facial nerve injury increases with tumor size and previous treatments
Contraindications to Certain Approaches
- Ear irrigation should not be performed in patients with tumors involving the tympanic membrane as it may cause:
Follow-up Care
- First MRI at 6-12 months post-surgery 7
- Regular follow-up examinations to detect recurrence
- For vestibular schwannomas, subsequent MRIs at regular intervals based on extent of resection 7
Prognosis
- Benign tumors: Excellent prognosis with complete surgical excision (recurrence rate <1.5%) 1
- Malignant tumors: Prognosis worsens with advancing tumor stage; early diagnosis is critical 3
- Vestibular schwannomas: Good outcomes with proper selection of treatment modality 6
The key to successful management is early diagnosis, appropriate surgical approach based on tumor characteristics, and multidisciplinary care involving otolaryngologists, neurosurgeons, and radiation oncologists when necessary.