What is the recommended treatment for a dermoid cyst?

Treatment of Dermoid Cysts

Complete surgical excision is the definitive treatment for dermoid cysts, regardless of location, to prevent recurrence and potential complications. 1, 2

Ovarian Dermoid Cysts

Premenopausal Patients (<10 cm)

• For typical dermoid cysts <10 cm in premenopausal women, annual ultrasound surveillance is recommended if not surgically excised, with optional initial follow-up at 8-12 weeks based on diagnostic confidence. 1
• The risk of malignant degeneration in sonographically diagnosed dermoids is quite low when followed with yearly ultrasound. 1
• Patients are typically managed under gynecologic care. 1

Postmenopausal Patients

• Annual ultrasound follow-up may be considered for confidently diagnosed dermoid cysts when not surgically excised, though the threshold for surgical intervention should be lower than in premenopausal patients. 1
• If changing morphology or developing vascular components are detected, refer to ultrasound specialist or obtain MRI in premenopausal patients; direct MRI referral is recommended for postmenopausal patients. 1

Surgical Approach for Ovarian Dermoids

• Laparoscopic surgery is the preferred surgical approach, feasible in over 86% of cases, with conservative ovarian-sparing cystectomy possible in >80% of cases. 3
• Intraperitoneal cystectomy without opening the cyst, using an impermeable endoscopic sack, prevents chemical peritonitis from spillage. 3
• Vaginal approach with laparoscopic assistance offers advantages including shorter operating time and reduced intraperitoneal spillage compared to total laparoscopic removal. 4
• Recurrence risk after conservative laparoscopic treatment is approximately 4%. 3

Neck Dermoid Cysts

Diagnostic Evaluation

• MRI is the preferred imaging modality for surgical planning, showing characteristic fatty and calciferous content that may be pathognomonic. 2
• Ultrasound demonstrates hyperechoic components with acoustic shadowing, hyperechoic lines and dots, and sometimes fluid-fluid levels. 1, 2
• Physical examination should assess for features suggesting malignancy: mass present ≥2 weeks without fluctuation, fixed to adjacent tissues, firm consistency, >1.5 cm, or overlying skin ulceration. 2

Surgical Management

• Complete surgical excision is mandatory for neck dermoid cysts, with the surgical approach planned based on location and extent. 2
• Fine needle aspiration should be performed instead of open biopsy if malignancy risk is elevated and diagnosis remains uncertain. 2

Antibiotic Use

• Antibiotics are NOT routinely recommended for inflamed dermoid cysts unless complicating factors exist: multiple lesions, cutaneous gangrene, severely impaired host defenses, extensive surrounding cellulitis, or severe systemic infection manifestations. 1, 2
• Gram stain and culture of pus from inflamed epidermoid cysts are not recommended. 1, 2

Scalp Dermoid Cysts

Pediatric Management

• Early surgical excision is recommended for scalp dermoids in children to prevent complications from cyst growth, including bone erosion and potential intracranial extension. 5, 6
• Excision is safe even in young patients, with 32.9% of patients operated on before age 1 year and 48.7% between ages 1-3 years. 5
• Comprehensive evaluation with both MRI and CT imaging is essential to assess for intracranial and/or intradural extension before surgery. 6
• Frontal and pterional locations show significant association with bone erosion. 5

Key Clinical Pitfalls

• Never assume a cystic mass is benign without definitive diagnosis; evaluation should continue until diagnosis is confirmed. 2
• The risk of malignancy in classic benign-appearing dermoid cysts on ultrasound is <1%, with malignant transformation more common in older patients. 1, 2
• For ovarian dermoids, changing morphology or developing vascularity warrants immediate advanced imaging or specialist referral. 1
• Document follow-up plans and criteria triggering additional evaluation. 2