title: Learning curve for endobronchial ultrasound‑guided transbronchial needle aspiration: experience of a community‑based teaching hospital.
abstract: Endobronchial ultrasound‑guided transbronchial needle aspiration (EBUS‑TBNA) is a minimally invasive procedure. This procedure is useful for nodal staging of lung cancer and evaluating mediastinal lymphoma and granuloma. The present study was a retrospective analysis of our experience when EBUS‑TBNA was initially implemented. A total of 112 lymph nodes/masses (51 patients) were divided into two groups: The first and second 8 months. In the first group, 33 lymph nodes/masses (16 patients) were biopsied and tumor diagnoses were made in 9% of the cases (three lymph nodes/masses). The material was adequate to produce a cell block for microscopic analysis in 42% of cases. Subsequent tissue diagnoses were available in 50% of cases. Only one of the three malignant EBUS‑TBNA diagnoses (33%) was confirmed by histological examination. In the second 8 months, 79 lymph nodes (35 patients) were sampled. Tumor/granuloma diagnoses were achieved in 27% of the cases (21 nodes) (P=0.045 versus the first 8 months) and the obtained material was adequate for producing a cell block in 90% of cases (P<0.001 versus the first 8 months). Corresponding tissue diagnoses were available in 28% of cases. Correlation of EBUS-TBNA and histological examination for tumor/granuloma diagnosis was 100% (12/12, P=0.029 versus the first 8 months). Immunostains in the cell blocks indicated that all the metastatic adenocarcinomas were thyroid transcription factor‑1 (TTF‑1)+ and p63‑, and that all squamous cell carcinomas were TTF‑1‑, p63+ and cytokeratin 5/6 (CK5/6)+. Eight granulomata were identified, of which five were positive for Acid‑Fast Bacilli (AFB) stain and confirmed by culture or tissue biopsy. The remaining three granulomata were AFB‑negative. EGFR/KRAS mutation analysis was conducted in cell blocks of five adenocarcinomas, of which all provided sufficient diagnostic material. The findings showed a steep learning curve when EBUS‑TBNA was first adopted, reflected by an increased rate of tumor/granuloma diagnoses as well as an improved sample yield for cell block preparation in the second 8 months. TTF‑1, p63 and CK5/6 were useful biomarkers for distinguishing metastatic lung carcinomas.
authors.affiliation: Department of Laboratory Medicine and Pathology, Newark Beth Israel Medical Center, Barnabas Health System, Newark, New Jersey 07112, USA.
authors.forename: He
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Laboratory Medicine and Pathology, Newark Beth Israel Medical Center, Barnabas Health System, Newark, New Jersey 07112, USA.
authors.forename: Cyril
authors.initials: C
authors.lastname: D'Cruz
authors.affiliation: Department of Laboratory Medicine and Pathology, Newark Beth Israel Medical Center, Barnabas Health System, Newark, New Jersey 07112, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Yam
authors.affiliation: Department of Laboratory Medicine and Pathology, Newark Beth Israel Medical Center, Barnabas Health System, Newark, New Jersey 07112, USA.
authors.forename: Lorie M
authors.initials: LM
authors.lastname: Dilla
authors.affiliation: Department of Laboratory Medicine and Pathology, Newark Beth Israel Medical Center, Barnabas Health System, Newark, New Jersey 07112, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Tsang
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000556:secondary; D044963:Biopsy, Fine-Needle; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000556:secondary; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration; D006764:Hospitals, Community; D006784:Hospitals, Teaching; D006801:Humans; D059032:Learning Curve; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies