Durable response of anaplastic thyroid cancer to pembrolizumab combined with chemotherapy: A case report

Anaplastic thyroid cancer is a notoriously aggressive malignancy with a dismal prognosis, typically associated with a median overall survival of less than one year. Therapeutic alternatives are particularly limited for patients without actionable driver mutations. Here, we report a case of BRAF V600E wild-type, PD-L1-positive (tumor proportion score of 80%) anaplastic thyroid cancer with residual/relapsed disease following surgery and subsequent progression on multi-targeted tyrosine kinase inhibitor therapy. The patient was thereafter treated with a combination of pembrolizumab, nab-paclitaxel and carboplatin, resulting in a sustained near-complete response lasting over 30 months, accompanied by a manageable safety profile. The favorable response in this case suggests that further evaluation of this triplet regimen could be considered for anaplastic thyroid cancer, though this remains a speculative premise requiring validation. Further studies are also needed to clarify the underlying mechanisms of this combination and to identify predictive biomarkers for patient selection.