Increased iodine uptake in the Nabothian cyst

Area of Science:

• Oncology
• Nuclear Medicine
• Radiology

Background:

• Papillary thyroid cancer (PTC) is the most common type of thyroid malignancy.
• Radioiodine (131I) therapy is a standard treatment for residual or metastatic PTC.
• Post-therapy whole-body scans (RxWBS) are used to assess treatment effectiveness and detect recurrence.

Observation:

• A 31-year-old female patient with a history of PTC underwent radioiodine therapy.
• A post-therapy SPECT scan revealed unexpected focal iodine accumulation in the cervix.
• This finding prompted further investigation to determine its origin.

Findings:

• Ultrasound examination identified the cervical iodine uptake as a Nabothian cyst.
• Nabothian cysts are benign cervical inclusion cysts and do not represent thyroid cancer recurrence.
• This case highlights a potential imaging pitfall in post-treatment PTC surveillance.

Implications:

• Benign cervical structures like Nabothian cysts can mimic metastatic disease on radioiodine scans.
• Careful correlation with anatomical imaging (e.g., ultrasound) is crucial for accurate interpretation.
• Understanding these benign mimics can prevent unnecessary patient anxiety and further invasive investigations.