TY - JOUR
T1 - Papillary Thyroid Carcinoma Emerging from Hashimoto Thyroiditis Demonstrates Increased PD-L1 Expression, Which Persists with Metastasis
AU - Lubin, Daniel
AU - Baraban, Ezra
AU - Lisby, Amanda
AU - Jalali-Farahani, Sahar
AU - Zhang, Paul
AU - Livolsi, Virginia
N1 - Publisher Copyright:
© 2018, Springer Science+Business Media, LLC, part of Springer Nature.
PY - 2018/12/1
Y1 - 2018/12/1
N2 - There is evidence that programmed death-ligand 1 (PD-L1) is expressed by thyroid follicular epithelium in thyroiditis, but the role of PD-L1 in papillary thyroid carcinoma (PTC) is poorly understood. We aimed to determine whether (1) the presence of background chronic lymphocytic thyroiditis (CLT) or Hashimoto thyroiditis (HT) influenced the expression of PD-L1 in benign follicular epithelium or in PTC and (2) if PD-L1 expression in PTC persisted with lymph node metastasis. We performed immunohistochemistry (IHC) for PD-L1 on formalin-fixed paraffin-embedded tissues. We first studied five cases of unremarkable thyroid, five cases of CLT, and five cases of HT without carcinoma. We subsequently performed PD-L1 IHC on ten cases of PTC arising in normal thyroid, ten cases of PTC arising in CLT, and ten cases of PTC arising in HT. Whenever available, we evaluated corresponding synchronous lymph node metastases from all cases for PD-L1 expression. PD-L1 expression was increased (10–90%) in all five cases of HT, only minimal expressed (1–5%) in two of five cases of CLT, and not expressed in five cases of unremarkable thyroid. PTC arising in normal thyroid or CLT nearly uniformly lacked PD-L1 expression. In contrast, PTC arising in HT demonstrated significant PD-L1 expression, which persisted in corresponding lymph node metastases. Background non-neoplastic follicular epithelium in the HT cases also demonstrated PD-L1 expression. Thyroid follicular epithelium in HT demonstrates increased PD-L1 expression, and PTC arising in a background of HT shows increased PD-L1 expression, which is retained with metastasis.
AB - There is evidence that programmed death-ligand 1 (PD-L1) is expressed by thyroid follicular epithelium in thyroiditis, but the role of PD-L1 in papillary thyroid carcinoma (PTC) is poorly understood. We aimed to determine whether (1) the presence of background chronic lymphocytic thyroiditis (CLT) or Hashimoto thyroiditis (HT) influenced the expression of PD-L1 in benign follicular epithelium or in PTC and (2) if PD-L1 expression in PTC persisted with lymph node metastasis. We performed immunohistochemistry (IHC) for PD-L1 on formalin-fixed paraffin-embedded tissues. We first studied five cases of unremarkable thyroid, five cases of CLT, and five cases of HT without carcinoma. We subsequently performed PD-L1 IHC on ten cases of PTC arising in normal thyroid, ten cases of PTC arising in CLT, and ten cases of PTC arising in HT. Whenever available, we evaluated corresponding synchronous lymph node metastases from all cases for PD-L1 expression. PD-L1 expression was increased (10–90%) in all five cases of HT, only minimal expressed (1–5%) in two of five cases of CLT, and not expressed in five cases of unremarkable thyroid. PTC arising in normal thyroid or CLT nearly uniformly lacked PD-L1 expression. In contrast, PTC arising in HT demonstrated significant PD-L1 expression, which persisted in corresponding lymph node metastases. Background non-neoplastic follicular epithelium in the HT cases also demonstrated PD-L1 expression. Thyroid follicular epithelium in HT demonstrates increased PD-L1 expression, and PTC arising in a background of HT shows increased PD-L1 expression, which is retained with metastasis.
KW - Hashimoto thyroiditis
KW - Metastasis
KW - Papillary thyroid carcinoma
KW - Programmed death-ligand 1
KW - Thyroid
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U2 - 10.1007/s12022-018-9540-9
DO - 10.1007/s12022-018-9540-9
M3 - Article
C2 - 30121940
AN - SCOPUS:85052208603
SN - 1046-3976
VL - 29
SP - 317
EP - 323
JO - Endocrine Pathology
JF - Endocrine Pathology
IS - 4
ER -