Endocrine Abstracts

Introduction: Anaplastic thyroid carcinoma (ATC) carries an extremely poor prognosis. The reported median survival time is 3-9 months and one year survival rate is 18-20%. Here we report 4 cases of ATC.

Case reports: Case 1: An 82 year-old female presented with rapidly progressive anterior neck swelling. She underwent hemi-thyroidectomy and D1 dissection. Pathological diagnosis was ATC, T4aN0. External beam radiotherapy (EBRT) to the whole neck was administered. Because lung metastasis was detected four weeks after the surgery, she received weekly paclitaxel. Although partial response was observed, paclitaxel was discontinued due to the myelosuppression. She died of a respiratory failure 13 months after the surgery.

Case 2: A 54 year-old male presented with hoarseness. He underwent hemi-thyroidectomy and D1 dissection. Pathological diagnosis was poorly differentiated carcinoma, T4aN1a. Neck and lung metastasis was detected seven months after the surgery and he underwent total thyroidectomy and D1 dissection. Pathological diagnosis was ATC, T4bN1a. He received EBRT and weekly paclitaxel for eleven months. Although partial response was observed, paclitaxel was discontinued due to the patient’s will. He died 13 months after the second surgery.

Case 3: A 70 year-old female presented with anterior neck swelling. She underwent total thyroidectomy, D2 dissection, and tracheostomy. Pathological diagnosis was ATC, T4aN1bM1. She received EBRT and weekly paclitaxel. Although stable disease was observed, she died of tracheal bleeding 6 months after the surgery.

Case 4: A 74 year-old female presented with anterior neck swelling. She underwent total thyroidectomy and D2 dissection, followed by adjuvant I-131 therapy. Retropharyngeal lymph node and lung metastasis were detected 2 years after the surgery. Fine needle aspiration cytology indicated ATC. Lenvatinib was administered for seven months. Although partial response was observed, she died due to massive bleeding from the tumor.

Discussion: Although NCCN guideline recommends paclitaxel as one of the systemic therapy regimens for ATC, paclitaxel is not covered by the public health insurance in Japan. Iwasaki et al reported a survival benefit of lenvatinib compared with palliative therapy including weekly paclitaxel. A meta-analysis by Huang et al showed a meaningful but limited clinical efficacy of lenvatinib for ATC. A careful administration is required to avoid massive bleeding when the lesions are close to large vessels.

Conclusion: A Randomized controlled trial with a sufficient sample size is needed to confirm the efficacy and safety of lenvatinib for ATC compared with paclitaxel.