The optimal approach of EBUS-FNA rapid on-site evaluation (ROSE): a five-year experience from a large academic medical center.

INTRODUCTION: Rapid on-site evaluation (ROSE) performed during endobronchial ultrasound-guided fine needle aspiration (EBUS-FNA) has shown significant value. However, ROSE may not be available for some pulmonary centers. Performing ROSE can be challenging and stressful due to time constrains for preparing, staining and reviewing the cytology slides between passes. MATERIALS AND METHODS: A retrospective cytology report review of EBUS-FNA procedures performed between October 2014 and May 2019 revealed 516 cases that were included in the study. The number of passes for each procedure was documented. The adequacy rates were assessed at 4 different study points; ≤3 passes, ≤5 passes, at odd passes only, and the even passes only. The study groups results were compared to the overall ROSE and the final cytology adequacy. RESULTS: The overall ROSE interpretation was adequate in 370 (71.7%) and inadequate in 146 (28.3%). After reviewing the Papanicolaou stained slides and cell blocks, the final cytology results were adequate in 473 (91.7%) and inadequate in 43 (8.3%) of the cases. The number of passes per procedure ranged from 1 to 17. Our results showed that ROSE evaluation of the first 5 passes during the EBUS-FNA procedure could achieve the similar adequacy rate compared to the overall ROSE evaluation of all the passes. CONCLUSIONS: To achieve the most benefits of ROSE and to reduce the procedure time for EBUS-FNA, we recommend performing ROSE for ≤5 passes depending on the adequacy, and save all additional passes for cell blocks preparation if more than 5 passes are attempted.

Plasmablastic Lymphomas: Characterization of Tumor Microenvironment Using CD163 and PD-1 Immunohistochemistry.

This study aims to characterize the tumor microenvironment of plasmablastic lymphoma (PBL) in regard to the quantities of CD163(+) tumor associated macrophages (TAM) and PD1(+) tumor infiltrating lymphocytes (TIL). This article also reviews the existing knowledge of the role of PD-1/PD-L1 pathway in the tumor microenvironment of hematopoietic neoplasms, discusses potential mechanisms to explain our findings, and outlines areas for future studies. We performed CD163 and PD1 immunohistochemical studies in 11 cases classified as plasmablastic lymphoma, and recorded the percentages of positive TAMs and TILs. Based on previous studies, cut off values of ≥30% and >5% were used to classify the cases into high TAMs and TILs, respectively. We determined that the majority of cases (8 of 11, or 73%) had high percentage of TAMs, while only a minority had high percentage of TILs (3 of 11, or 27%). Our data shows a trend towards a negative correlation between TAMs and TILs (p=0.08), and a predominance of the pattern TAMhigh/TILlow (7 of 11, or 63%) compared to other patterns. The microenvironment of plasma-blastic lymphoma tends to show high percentage of TAMs (≥30%) combined with low percentage of TILs (≤5%). Additional studies are needed to determine the clinical significance of TILs and the influence of EBV and HIV infections on numbers of TILs in PBL. As high microenvironment TAMs have been associated with high microenvironment PD-L1 in other hematopoietic malignancies, our data supports the need for future studies on the expression of PD-L1 in PBL.