What is the treatment for an epidermoid cyst?

Treatment for Epidermoid Cysts

Incision and drainage is the recommended treatment for inflamed epidermoid cysts, while complete surgical excision is the definitive treatment for non-inflamed epidermoid cysts to prevent recurrence. 1

Diagnosis and Evaluation

• Epidermoid cysts (often incorrectly called "sebaceous cysts") are common benign lesions that appear as dome-shaped nodules
• Clinical hallmark: presence of an epidermal punctum (small central opening)
• Most common locations: face (65%), trunk (10.9%), scalp (7.9%), and neck (7.9%) 2
• More common in adults, with higher prevalence in men than women (3:2 ratio) 2

Treatment Algorithm

For Non-inflamed Epidermoid Cysts:

1. Complete surgical excision is the treatment of choice to prevent recurrence 3

   • Options include:
     • Standard excision with 2-3 mm margins
     • Minimal excision technique: 2-3 mm incision, expression of contents, and extraction of cyst wall 4

2. Important surgical considerations:

   • Complete removal of the cyst wall is essential to prevent recurrence 3
   • Gram stain and culture of cyst contents are NOT recommended 1
   • Histopathological evaluation is only necessary if unusual findings or suspicion of malignancy exists 4

For Inflamed Epidermoid Cysts:

1. Incision and drainage is the recommended first-line treatment 1

   • Make an incision over the fluctuant area
   • Thoroughly evacuate all pus
   • Break up loculations by probing the cavity
   • Simple dry dressing is usually sufficient for wound care

2. Post-drainage management:

   • Systemic antibiotics are rarely necessary 1
   • Consider antibiotics only in cases with:
     • Multiple lesions
     • Severely impaired host defenses
     • Extensive surrounding cellulitis
     • Systemic signs of infection (fever, SIRS)

3. Timing of definitive treatment:

   • Consider postponing complete excision until inflammation has subsided 4
   • Inflamed cysts are more difficult to excise completely

Special Considerations

• For inflamed cysts with systemic inflammatory response syndrome (SIRS), consider antibiotics active against Staphylococcus aureus 1

  • Signs of SIRS include:
    • Temperature >38°C or <36°C
    • Tachypnea >24 breaths per minute
    • Tachycardia >90 beats per minute
    • White blood cell count >12,000 or <400 cells/µL

• Wound closure options after excision:

  • Simple covering with dry dressing is often most effective 1
  • Some clinicians pack with gauze or suture closed

Common Pitfalls to Avoid

1. Incomplete removal of cyst wall - leads to recurrence 3
2. Misdiagnosis - epidermoid cysts can be confused with other lesions; histopathological confirmation may be needed in atypical cases
3. Unnecessary antibiotic use - most uncomplicated epidermoid cysts do not require antibiotics 1
4. Attempting excision during active inflammation - more difficult and may lead to incomplete removal 4
5. Failure to protect from cyst contents - use gauze or splatter shield during drainage to prevent spraying of contents 4

The surgical approach has a low complication rate (approximately 2.2%) when performed properly 3, making it a safe and effective treatment option for epidermoid cysts.