Chronic Lymphocytic Thyroiditis with Oncocytic Metaplasia Influences PD-L1 Expression in Papillary Thyroid Carcinoma.

BACKGROUND: Despite the increasing recognition of PD-L1 as predictor of immunotherapeutic response in various malignancies, its role and prognostic significance in thyroid cancer remain underexplored and subject to debate. This study begins to address this gap by comprehensively analyzing PD-L1 expression in papillary thyroid carcinoma (PTC) and investigating its correlation with key clinicopathological variables. METHODS: We conducted immunohistochemistry (IHC) to assess PD-L1 expression in whole-tissue sections from 121 primary papillary thyroid carcinoma (PTC) cases. We then analyzed the correlations between PD-L1 expression and various clinicopathological variables. RESULTS: PD-L1 expression was detected in 33.1% of papillary thyroid carcinomas (PTCs), predominantly exhibiting weak to moderate intensity. Notably, this study found no significant correlation between PD-L1 expression and various clinicopathological variables. The lack of association with traditional factors such as age, sex, histological subtype, and tumor size suggests the complex and multifaceted nature of PD-L1 regulation in PTC. Multivariate logistic regression analysis identified chronic lymphocytic thyroiditis with oncocytic metaplasia as the sole independent predictor of PD-L1 expression (P = 0.014), underlining the potential influence of the tumor microenvironment on immune checkpoint expression in PTC. CONCLUSIONS: Our study underscores the intricate interplay between chronic lymphocytic thyroiditis with oncocytic metaplasia and PD-L1 expression in papillary thyroid carcinoma. The observed link suggests a potential avenue for therapeutic intervention using anti-PD-1/PD-L1 therapies in surgery-refractory PTC. Understanding the dynamics of immune checkpoint regulation in the context of the tumor microenvironment is crucial for devising effective treatment strategies. Future research endeavors should delve deeper into the molecular mechanisms underlying this interaction and explore its implications for patient outcomes. As the field of immunotherapy continues to evolve, our findings contribute valuable insights into the complex immunological landscape of thyroid cancer.

Malignant pleural effusion in multiple myeloma: a case report / Derrame pleural malign em mieloma múltiplo: relato de caso

Multiple myeloma (MM) is a malignant neoplasm of monoclonal plasma cells that accumulate in bone marrow (BM). Malignant pleural effusions (MPE), as part of multiple myeloma clinical presentation, are unusual. Is even more rare as the first sign of presentation, occurring in less than 1% of the cases. The most common associated immunoglobulin with malignant pleural effusions is IgA subtype (80%). This condition carry a poor prognosis. We aim to describe a refractory case of multiple myeloma with extensive disease that presented with extramedullary relapse with malignant pleural effusions , besides discussing the importance of differential diagnosis.

O mieloma múltiplo (MM) é uma neoplasia maligna de células plasmáticas monoclonais que se acumulam na medula óssea (MO). Os derrames pleurais malignos (EPM), como parte da apresentação clínica do mieloma múltiplo, são incomuns. É ainda mais raro como primeiro sinal de apresentação, ocorrendo em menos de 1% dos casos. A imunoglobulina associada mais comum a derrames pleurais malignos é o subtipo IgA (80%). Esta condição carrega um mau prognóstico. Nosso objetivo é descrever um caso refratário de mieloma múltiplo com doença extensa que apresentou recidiva extramedular com derrame pleural maligno, além de discutir a importância do diagnóstico diferencial