In a 28-year-old woman with a 1.2 cm hyperechoic ovarian lesion and normal tumor markers (CA‑125, AFP, β‑hCG, LDH), what is the likely diagnosis and recommended management?

Likely Diagnosis: Dermoid Cyst (Mature Cystic Teratoma)

In a 28-year-old woman with a 1.2 cm hyperechoic ovarian lesion and normal tumor markers, the most likely diagnosis is a dermoid cyst, and the recommended management is optional follow-up at 8-12 weeks with consideration for annual ultrasound surveillance if not surgically removed. 1

Diagnostic Reasoning

The hyperechoic appearance is the key imaging characteristic that points toward a dermoid cyst. According to O-RADS US guidelines, typical dermoid cysts demonstrate:

• Hyperechoic component with acoustic shadowing
• Hyperechoic lines and dots (representing hair)
• Floating echogenic spherical structures (pathognomonic when present) 1

The normal tumor markers (CA-125, AFP, β-hCG, LDH) strongly support a benign diagnosis. While these markers can be elevated in various ovarian malignancies 2, their normal values in this premenopausal patient with a small hyperechoic lesion effectively rule out germ cell tumors and epithelial malignancies.

Risk Stratification

This lesion falls into O-RADS 2 (almost certainly benign, <1% risk of malignancy) when the typical dermoid features are confidently identified and the lesion is <10 cm 1.

At 1.2 cm, this is well below the 10 cm threshold that would trigger more aggressive management.

Management Algorithm

For This Specific Patient (Premenopausal, <10 cm Dermoid):

1. Initial approach: Optional follow-up ultrasound at 8-12 weeks based on confidence in diagnosis 1

2. If not surgically removed: Annual ultrasound surveillance should be considered 1

3. Indications for escalation:

   • Changing morphology
   • Development of vascular component on color Doppler
   • Enlargement beyond 10 cm

   → If any of these occur: Refer to ultrasound specialist, gynecologist, or obtain MRI 1

Critical Pitfalls to Avoid

Do not confuse with other hyperechoic lesions: The reticular pattern of hemorrhagic cysts can appear hyperechoic but demonstrates:

• Concave margins of retracting clot
• Fine intersecting lines (fibrin strands)
• Absence of acoustic shadowing
• No internal vascularity 1

Size matters for management: While this 1.2 cm lesion requires minimal intervention, dermoid cysts ≥10 cm automatically escalate to O-RADS 3 (1-10% malignancy risk) and require gynecologic management regardless of typical features 1

Postmenopausal patients differ: In postmenopausal women, even typical dermoid cysts carry higher risk of malignant transformation and warrant more aggressive surveillance or surgical consideration 1

Why Surgery Is Not Immediately Indicated

The patient's premenopausal status, small lesion size (<10 cm), typical benign imaging features, and normal tumor markers collectively indicate extremely low malignancy risk. Immediate surgery would represent overtreatment for a lesion with <1% malignancy probability 1.

However, patients are typically under gynecologic care, and surgical excision remains an option based on patient preference, symptoms, or concern about future torsion risk—though at 1.2 cm, torsion risk is minimal.