MON-408 - An Unyielding Thyroid: A Case of Treatment Resistant Papillary Thyroid Carcinoma

Introduction

Papillary thyroid carcinoma (PTC) is one of the most common malignancies of the thyroid gland. It occurs more frequently in younger to middle-aged adults and demonstrates a higher prevalence among women. Despite its generally favorable prognosis, PTC is typically managed with surgical thyroidectomy and, in selected cases, radioactive iodine ablation. While these treatment modalities are often curative, disease recurrence can occur. This case highlights a patient with recurrent PTC following thyroidectomy, illustrating challenges in long-term management.

Case

A 36-year-old woman with a history of papillary thyroid carcinoma status post thyroidectomy presented for evaluation. She was initially diagnosed with metastatic PTC in 2013 and underwent thyroidectomy at that time, which was considered successful. Following surgery, she reported persistent throat discomfort and increased mucus production. Subsequently, the patient lost medical insurance coverage and was lost to follow-up. In 2017, she noted a new growth along the side of her neck, prompting renewed medical evaluation. Further workup confirmed recurrent disease, and she underwent repeat surgical resection, with pathology again consistent with PTC. Postoperatively, she was prescribed levothyroxine 137 mcg daily. However, due to ongoing insurance limitations, she was unable to obtain her medication consistently. She attempted to acquire levothyroxine through nontraditional means but was unsuccessful. Laboratory evaluation in August 2025 revealed significant hypothyroidism, with a thyroid-stimulating hormone (TSH) level of 67.200 µIU/mL and a free thyroxine (T4) level of 0.55 ng/dL. After appropriately resuming levothyroxine 137 mcg daily, repeat laboratory testing approximately one month later demonstrated improvement, with a TSH of 7.42 µIU/mL and a free T4 of 2.02 ng/dL.

Conclusion

Papillary thyroid carcinoma is a highly treatable endocrine malignancy with excellent overall outcomes following surgical and adjunctive therapies. However, recurrence may occur despite definitive initial treatment, necessitating additional surgical intervention and long-term surveillance. This case underscores the importance of consistent follow-up and uninterrupted thyroid hormone replacement, as well as the potential consequences of barriers to care in the management of recurrent thyroid cancer.

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