Complete Disappearance of Low-Risk Papillary Thyroid Microcarcinoma following Microwave Ablation: First Case Report of Any Thermal Ablation from Bangladesh

Background: Papillary Thyroid Microcarcinoma (PTMC) is generally associated with an excellent prognosis and surgery remains the standard treatment. However, minimally invasive thermal ablation techniques, including Microwave Ablation (MWA) have emerged as effective alternatives for carefully selected patients with low-risk PTMC who decline surgery. This is the first reported case from Bangladesh describing the successful treatment of PTMC using any thermal ablation technique (Radiofrequency Ablation or Microwave Ablation or Laser Ablation). Case Presentation: A 27-year-old woman with hypertension and subclinical hypothyroidism presented with neck swelling. Neck ultrasonography revealed a 1.03 × 0.94 × 0.97 cm hypoechoic thyroid nodule with microcalcifications (ACR TIRADS5) in the right thyroid lobe without cervical lymphadenopathy. Fine-needle aspiration cytology performed twice showed benign cytology (Bethesda II) however, core needle biopsy confirmed papillary thyroid carcinoma. After declining thyroidectomy, the patient underwent ultrasound-guided microwave ablation using a trans-isthmic approach with hydrodissection. The procedure was completed successfully without complications. Results: Serial ultrasonography demonstrated an expected transient increase in lesion size immediately after ablation, followed by progressive volume reduction. Complete disappearance of the treated lesion was achieved at 9 months, with no evidence of local recurrence or cervical lymph node metastasis after 2 years 1month of follow-up. Thyroid function remained stable throughout follow-up without increasing the levothyroxine dose, and no procedure-related complications occurred. Conclusion: Ultrasound-guided microwave ablation was safe, feasible and effective in this patient with low-risk PTMC who declined surgery. This case represents the first reported thyroid thermal ablation case from Bangladesh and supports the potential role of MWA as a minimally invasive alternative to surgery in carefully selected patients. Further prospective studies with longer follow-up are needed to establish long-term oncological outcomes. Chatt Maa Shi Hosp Med Coll J; Vol.25 (2); July 2026; Page 129-133