Endosonografisch gestützte Biopsie: diagnostischer Ertrag, Fallstricke, Qualitätssicherung

Abstract

Endoscopic ultrasound-guided biopsies have proven to be of significant value in the diagnostic evaluation of benign and malignant diseases, as well as in the staging of malignant tumours of the gastrointestinal tract and adjacent organs. The high prognostic and therapeutic relevance of the resulting cytopathological diagnoses necessitates a shared responsibility of endosonographer and cytopathologist. Quality control programs are required. The diagnostic yield of endoscopic ultrasound-guided biopsies depends on the location, size and characteristics of target tissues, and technical factors (i. e., type of needle used, biopsy technique, and material processing). Other weighing factors include training, expertise and interaction of the endosonographer with cytopathologists. On-site cytological evaluation, which has proven to be successful in optimising the diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration biopsy, is notably practiced in Northern American and French academic institutions. It seems to be a sensible alternative to collect specimens for histological and immunohistochemical investigations in addition to the cytological smears in consideration of the economic and structural terms in the German health-care system. Endoscopic ultrasound-guided fine-needle aspiration succeeds in harvesting core biopsies in 3 out of 4 cases with 22-gauge needles. Therefore the use of 19-gauge needles for endoscopic ultrasound-guided aspiration or trucut biopsy may be necessary only in selected cases.

Endobronchial ultrasound‐guided transbronchial needle aspiration cytology: a state of the art review

“…19 Similarly, studies that have not used onsite evaluation for EUS-FNA of mediastinal lymph nodes also had a lower sensitivity [80% (72-86%) versus 88% (80-93%)]. 65 In some institutions cytotechnologists successfully perform on-site evaluations for adequacy, although they may not confidently provide a preliminary diagnosis. However, on-site evaluation by cytopathologists requires special expertise and training, is time-consuming 47,63 and may not be adequately reimbursed.…”

“Clinical” cytology for endoscopists: A practical guide

“…Increasing diameter of the needle also increases blood contamination of the specimen and the cytological quality of the specimen worsens due to bigger cell blocks which cannot be analyzed in conventional smears. [12] Therefore, 22-gauge needles are not widely used in clinical practice. [13]…”

Quality Assurance in Endoscopy: Which Parameters?

“…This information is, among others, important for the cytopathological diagnosis and for the estimation of the quality of the technical performance. It allows a correlation with the result quality [66,70]. All of the mentioned intra-procedural quality indicators are evaluated in the ASGE recommendation [66] with a quality target of >98%.…”