What is the treatment for a sebaceous cyst on the head?

Treatment of Sebaceous Cyst on the Head

Surgical excision with complete removal of the cyst wall is the definitive treatment for sebaceous cysts on the scalp, with the timing and approach depending on whether the cyst is inflamed or uninflamed.

Initial Assessment: Inflamed vs. Uninflamed

The first critical step is determining whether the cyst is currently inflamed or infected, as this fundamentally changes your management approach 1, 2:

• Uninflamed cysts present as mobile, flesh-colored nodules with a characteristic central punctum, containing cheesy keratinous material 3
• Inflamed cysts present as a longstanding nodule that recently became painful, enlarged, and tender, containing thick white-yellow keratinous debris mixed with pus 1
• The inflammation in epidermoid cysts results from rupture of the cyst wall and extrusion of contents into the dermis—not true bacterial infection 3, 1

Management of Uninflamed Cysts

For asymptomatic or uninflamed cysts, perform elective complete excision with removal of the entire cyst wall to prevent recurrence 2, 4:

• Minimal excision techniques achieve excellent results with recurrence rates as low as 0.66% 4
• The scalp location allows for good cosmetic outcomes even with conventional excision 5, 4
• Complete wall removal is essential—leaving any portion of the cyst wall leads to recurrence 1, 2

Alternative Staged Approach

For large cysts or cosmetically sensitive areas, consider a two-stage laser-assisted technique 6:

• Stage 1: Use laser to create small opening and evacuate cyst contents 6
• Stage 2: Remove collapsed cyst wall with minimal excision approximately 1 month later 6
• This approach minimizes scarring while ensuring complete removal 6

Management of Inflamed/Infected Cysts

For inflamed cysts, perform incision and drainage as the cornerstone treatment, with or without immediate cyst wall excision depending on the degree of inflammation 1, 2:

Immediate Drainage Protocol

• Make adequate incision to thoroughly evacuate all contents 1
• Probe the cavity to break up all loculations 2
• The entire cyst wall should ideally be excised to prevent recurrence, which can be done in the same sitting under appropriate anesthesia 1
• Cover with dry dressing 2

When to Add Antibiotics

Antibiotics are generally unnecessary after adequate drainage unless specific criteria are met 1:

Add systemic antibiotics ONLY when:

• Temperature ≥38.5°C or systemic inflammatory response syndrome present 1
• Heart rate >110 beats/minute 1
• Erythema extending >5 cm from margins 1
• Severely immunocompromised host 1
• Incomplete source control after drainage 1
• Multiple lesions or extensive surrounding cellulitis 1

If antibiotics are indicated, use trimethoprim-sulfamethoxazole, clindamycin, or doxycycline for MRSA coverage, typically for 5-10 days 1.

Novel Approach for Infected Cysts

Recent evidence supports primary excision with closure even in infected cases 7:

• Excise infected tissue along with rim of healthy tissue under local or general anesthesia 7
• Close primarily with non-absorbable suture 7
• Remove stitches on day 21 for scalp locations 7
• This approach provides quick recovery, avoids frequent dressing changes, and is cost-effective 7

Critical Red Flags Requiring Biopsy

Always consider malignancy and obtain histopathologic evaluation when 3:

• Chronic lesion unresponsive to standard therapy 3
• Marked asymmetry or unifocal recurrent lesion 3
• Loss of normal tissue architecture or focal hair loss 3
• Rapid growth or ulceration 3
• Indurated, irregular borders or fixation to underlying structures 3
• Long-standing cysts (malignant transformation has been reported, though rare) 5

Common Pitfalls to Avoid

• Do not prescribe antibiotics alone without drainage—this is insufficient and leads to treatment failure 1
• Do not misdiagnose inflamed epidermoid cyst as simple abscess—the presence of a cyst wall requires different management to prevent recurrence 3, 1
• Do not perform inadequate drainage—complete evacuation and breaking up all loculations is essential 1
• Do not leave any portion of the cyst wall—incomplete removal guarantees recurrence 1, 2
• Do not obtain cultures of inflamed epidermoid cysts—they contain normal skin flora and inflammation is not primarily infectious 1