@article{AdamKircherSbieraetal.2021,
  author    = {Adam, Pia and Kircher, Stefan and Sbiera, Iuliu and Koehler, Viktoria Florentine and Berg, Elke and Kn{\"o}sel, Thomas and Sandner, Benjamin and Fenske, Wiebke Kristin and Bl{\"a}ker, Hendrik and Smaxwil, Constantin and Zielke, Andreas and Sipos, Bence and Allelein, Stephanie and Schott, Matthias and Dierks, Christine and Spitzweg, Christine and Fassnacht, Martin and Kroiss, Matthias},
  title     = {FGF-Receptors and PD-L1 in Anaplastic and Poorly Differentiated Thyroid Cancer: Evaluation of the Preclinical Rationale},
  series = {Frontiers in Endocrinology},
  volume    = {12},
  journal   = {Frontiers in Endocrinology},
  issn      = {1664-2392},
  doi       = {10.3389/fendo.2021.712107},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-244653},
  year      = {2021},
  abstract  = {Background Treatment options for poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinoma are unsatisfactory and prognosis is generally poor. Lenvatinib (LEN), a multi-tyrosine kinase inhibitor targeting fibroblast growth factor receptors (FGFR) 1-4 is approved for advanced radioiodine refractory thyroid carcinoma, but response to single agent is poor in ATC. Recent reports of combining LEN with PD-1 inhibitor pembrolizumab (PEM) are promising. Materials and Methods Primary ATC (n=93) and PDTC (n=47) tissue samples diagnosed 1997-2019 at five German tertiary care centers were assessed for PD-L1 expression by immunohistochemistry using Tumor Proportion Score (TPS). FGFR 1-4 mRNA was quantified in 31 ATC and 14 PDTC with RNAscope in-situ hybridization. Normal thyroid tissue (NT) and papillary thyroid carcinoma (PTC) served as controls. Disease specific survival (DSS) was the primary outcome variable. Results PD-L1 TPS≥50\% was observed in 42\% of ATC and 26\% of PDTC specimens. Mean PD-L1 expression was significantly higher in ATC (TPS 30\%) than in PDTC (5\%; p<0.01) and NT (0\%, p<0.001). 53\% of PDTC samples had PD-L1 expression ≤5\%. FGFR mRNA expression was generally low in all samples but combined FGFR1-4 expression was significantly higher in PDTC and ATC compared to NT (each p<0.001). No impact of PD-L1 and FGFR 1-4 expression was observed on DSS. Conclusion High tumoral expression of PD-L1 in a large proportion of ATCs and a subgroup of PDTCs provides a rationale for immune checkpoint inhibition. FGFR expression is low thyroid tumor cells. The clinically observed synergism of PEM with LEN may be caused by immune modulation.},
  language  = {en}
}