What are the management options for scalp cysts?

Management of Scalp Cysts

Surgical excision is the definitive treatment for scalp cysts, with complete removal of the cyst wall being essential to prevent recurrence, and early resection is recommended to avoid complications from progressive growth and bone erosion. 1, 2

Diagnostic Evaluation

Before surgical intervention, comprehensive imaging is critical when scalp dermoid or epidermoid cysts are suspected:

• MRI and CT imaging should be obtained to evaluate for potential intracranial or intradural extension, as some scalp dermoids can extend beyond the extracranial space 3
• Assess for bone involvement, as 21.94% of cysts erode through partial thickness of the cranium, 12.23% involve full thickness of the skull, and rare cases demonstrate epidural extension 2
• Frontal and pterional locations have significantly higher association with bone erosion compared to other scalp locations 2

Surgical Management

Timing of Intervention

• Early surgical excision is strongly recommended rather than conservative observation, even in young patients, to prevent complications from progressive growth 2
• Surgery is safe even in infants, with 32.9% of patients successfully operated on before 1 year of age and 48.7% between 1-3 years 2
• Do not delay surgery based on benign histology alone, as progressive enlargement can lead to cranial bone erosion, intracranial extension, infection, and malignant transformation 4, 1, 2

Surgical Technique

• Complete excision with removal of the entire cyst wall is mandatory to minimize risk of recurrence 1
• For simple extracranial cysts: elliptical excision with undermining of wound edges and primary closure with interrupted sutures 1
• For larger defects: rotational scalp flaps or island flaps can be used for reconstruction 4, 1
• When bone erosion is present: reconstruction may require addressing the osseous defect in addition to soft tissue closure 4
• For multiple cysts: staged excisions under general anesthesia are preferable to multiple procedures under local anesthesia, which increase recurrence risk 5

Anesthesia Considerations

• General anesthesia is preferred for definitive excision, particularly for multiple cysts or those requiring complex reconstruction 4, 5
• Local anesthesia alone is associated with higher recurrence rates when used for repetitive incomplete excisions 5

Histopathologic Confirmation

• All excised tissue must undergo histological examination to confirm the diagnosis and exclude malignant transformation 1
• Malignant transformation can occur toward squamous cell carcinoma, basal cell carcinoma, or Merkel cell carcinoma, though rare 1
• Clinical appearance alone cannot exclude malignancy; only histology provides definitive characterization 1

Alternative Treatments (Not Recommended as First-Line)

• Laser therapy with CO2 or erbium-YAG laser and intralesional triamcinolone acetonide injection are described but not recommended as primary treatment due to incomplete cyst wall removal and higher recurrence risk 1

Expected Outcomes

• Surgical excision has excellent safety profile with no major complications or recurrences reported in large case series when complete cyst wall removal is achieved 2
• Recurrence occurs primarily when cyst wall is incompletely removed or with inadequate initial surgical technique 1, 5

Common Pitfalls to Avoid

• Do not perform incomplete excisions leaving cyst wall remnants, as this guarantees recurrence 1, 5
• Do not rely on local anesthesia for complex or multiple cysts, as inadequate exposure leads to incomplete removal 5
• Do not skip imaging for suspected dermoid cysts, as intracranial extension fundamentally changes surgical planning 3
• Do not assume all scalp cysts are benign without histologic confirmation, as malignant transformation occurs 1