The clinical benefit of thin layer preparations with endoscopic ultrasound-guided fine-needle aspiration of masses: a prospective cohort study

In endoscopic ultrasound-with fine-needle aspiration (EUS-FNA) of masses, inserting part of the aspirate (or a separate aspirate) into CytoLyt is standard practice in our hospital, in addition to cytology slides. A thin layer preparation of this sample is then done in the pathology laboratory. It is not clear what the added value of such thin-layer preparation with CytoLyt is. Is This study is designed to examine the added value. In a 100 patients who undergo EUS-FNA of a mass, informed consent is asked. After the procedure, material is reviewed at a later time by two dedicated pathologists; first, only the cytology slides of a patient are reviewed, and a diagnosis is made if possible. Thus, a situation is simulated in which no thin-layer preparation is available. After this, the thin-layer preparation is given to the pathologists and all the material is again reviewed and a diagnosis is made if possible. samples are compared to the golden standard; surgical resection, histology or six months clinical follow-up. The difference between assessment with and without thin-layer preparations with regard to diagnostic yield and diagnostic accuracy is then calculated.

We hypothesize that diagnostic accuracy increases when, apart from cytologic samples, material is aspirated for thin layer preparation in endoscopic-ultrasound guided fine needle aspiration (EUS-FNA) of masses.

Baseline: Patient characteristics

6 months after EUSFNA: final diagnosis

No intervention is part of this study