Serial FNA allows direct sampling of malignant and infiltrating immune cells in patients with B‐cell lymphoma receiving immunotherapy

Abstract

BACKGROUND: Fine-needle aspiration (FNA) is used to diagnose malignancies, recurrences, and metastases. The procedure is quick and well tolerated and can be facilitated by ultrasound guidance. METHODS: This article describes the authors' experience in using serial FNA to harvest cellular material during 4 clinical trials of immunotherapy by in situ vaccination in patients with low-grade lymphoma. RESULTS: Two hundred ninety-six FNA samples were collected from 44 patients over a span of approximately 6 weeks for each patient. Samples were sufficient in quantity and quality to be analyzed by flow cytometry and/or single-cell messenger RNA sequencing. FNA samples yielded an average of 12 × 10 6 cells with a mean cellular viability of 86%. Material collected from the tumor lymph nodes differed significantly in the proportions and phenotypes of cellular populations in comparison with matched peripheral blood samples. A comparison of flow cytometry results obtained by FNA directly from the patient and by FNA performed ex vivo and a dissociation of the same lymph node after surgical excision confirmed that FNA sampling of the patient accurately represented the tumor and the microenvironment. An analysis of the FNA samples from immunotherapy-treated target lymph nodes versus nodes from nontreated tumor sites provided insight into the impact of specific immunotherapy regimens. CONCLUSIONS: This is the largest study describing the use of serial FNA sampling to harvest cellular material during immunotherapy clinical trials. The success of this technique opens the door for FNA sampling to expand significantly future investigations of the dynamic effects of investigational agents, be they immunotherapies or targeted therapies.

Comparison of fine‐needle aspiration techniques

“…Our cell viability ranged from 58% to 76%, and other reports describe a wide range from 30% to 90%. 5,12,21 Technique B had the highest total number of live cells and the second highest percentage viability. It was the only technique with a vacuum and air forced through the needle to expel the contents into media prior to flushing the needle with media.…”

“…FNA of the lymph nodes allows for longitudinal analysis of different cell subsets and, in some cases, lymphoid viral load with increased frequency. [5][6][7][8][9][11][12][13][14][15][16] It has also been efficacy, less invasive sampling techniques are essential. 8,11 Previous publications have demonstrated that the percentages of particular T lymphocytes correlated significantly or strongly, depending on the cell subset, between lymph node FNA and lymph node excisional biopsy.…”

“…8,11 Previous publications have demonstrated that the percentages of particular T lymphocytes correlated significantly or strongly, depending on the cell subset, between lymph node FNA and lymph node excisional biopsy. 5,6,8,11 It has also been demonstrated that serial sampling of lymph nodes by FNA does not affect the animal immune response, architecture of the lymph node, or interfere with future histological examination. 5,9,10,17 The technique for FNA of the lymph nodes has already been If a vacuum is engaged, the pressure in the syringe is released prior to withdrawing the needle from the lymph node.…”

“…5,6,8,11 It has also been demonstrated that serial sampling of lymph nodes by FNA does not affect the animal immune response, architecture of the lymph node, or interfere with future histological examination. 5,9,10,17 The technique for FNA of the lymph nodes has already been If a vacuum is engaged, the pressure in the syringe is released prior to withdrawing the needle from the lymph node. The aspirate is then expelled into the media, and the needle and syringe are normally flushed with the media.…”

“…1 FNA has proven to be an atraumatic, economical, and fairly rapid technique for obtaining biopsy results. [2][3][4][5][6] There are limitations with FNA compared to excisional biopsies, mainly with the cell yield; however, most studies report a range of 1 × 10 5-6 cells/collection, which is normally sufficient for immunophenotyping. 2,[4][5][6][8][9][10][11][12][13][14] The aim of this study was to compare the total live cells yield and viability of four different techniques for FNA in rhesus macaques.…”