What is the initial treatment for squamous cell carcinoma (SCC) of the ear?

Initial Treatment for Squamous Cell Carcinoma of the Ear

Mohs micrographic surgery (MMS) is the recommended initial treatment for squamous cell carcinoma of the ear due to the ear's high-risk anatomical location and the need for complete margin control while preserving tissue. 1, 2

Risk Classification and Treatment Selection

The ear is classified as a high-risk location (area H) for squamous cell carcinoma according to the American Academy of Dermatology guidelines 1. Treatment selection should follow this algorithm:

1. Confirm diagnosis with appropriate biopsy

   • Punch, shave, or excisional biopsy is recommended based on lesion characteristics
   • Ensure adequate depth and size to permit accurate diagnosis 1

2. Determine treatment based on risk assessment:

   • High-risk SCC of the ear (most cases):

     • First-line: Mohs micrographic surgery (MMS) 1, 2
     • MMS provides the lowest recurrence rates (4.1%) for ear SCC 3
     • Allows for tissue conservation in this cosmetically and functionally important area

   • Low-risk SCC of the ear (rare):

     • Standard excision with 4-6 mm margins to mid-subcutaneous adipose tissue 1, 2
     • Complete histologic margin assessment is essential

Important Considerations

• Avoid curettage and electrodessication (C&E) for ear SCC, as studies show higher recurrence rates for lesions on the ear treated with this method 1

• Radiation therapy should be considered only when:

  • Surgery is contraindicated or refused
  • As adjuvant therapy for high-risk features after surgery
  • Note: Cure rates may be lower than with surgical approaches 1

• Topical therapies (imiquimod, 5-FU) and photodynamic therapy are not recommended for invasive SCC of the ear 1

Rationale for MMS as First-line Treatment

• SCC of the ear has higher rates of local recurrence and metastasis compared to other sites 3, 4
• MMS allows for:
  • Complete margin control (critical for ear SCC)
  • Maximum tissue preservation in a cosmetically sensitive area
  • Lower recurrence rates (4.1-5.7%) compared to standard excision 3, 4
• Studies show SCC of the ear is predominantly found in older males (93.2% male, mean age 76) 3

Follow-up Recommendations

• Close surveillance during the first 2 years after surgery is critical, as most recurrences (>85%) occur within this timeframe 3, 4
• Consider lymph node evaluation in high-risk cases, as lymph node metastasis rates for ear SCC can reach 10% 3, 5

Caution

• Neglected or advanced SCC of the ear may require more extensive surgical resection and reconstruction, followed by adjuvant therapy 6
• Recurrent tumors are associated with larger initial size and greater subclinical spread 7