Prospective randomized trial to compare the safety, diagnostic yield and utility of 22-gauge and 19-gauge endobronchial ultrasound transbronchial needle aspirates and processing technique by cytology and histopathology.

INTRODUCTION: Endobronchial ultrasound (EBUS)-guided transbronchial needle aspirate (TBNA) is a widely used method of minimally invasive lymph node sampling. The benefit of processing samples by cytologic methods versus "core biopsy" is unclear. It is unknown if safety or diagnostic yield varies by needle gauge. MATERIALS AND METHODS: Between June 2018 and July 2019, 40 patients (56 lesions) undergoing EBUS TBNA lymph node evaluation were enrolled in this single-center prospective trial. Patients were chosen by permuted block randomization to undergo EBUS TBNA starting with 22-gauge (22g) or 19-gauge (19g) needles. Separate samples were sent for processing by cytologic methods and histopathology. Surgical pathologists and cytopathologists were blinded to needle size. The primary endpoint was diagnostic yield. Secondary endpoints compared specimen adequacy by rapid onsite evaluation (ROSE), sample adequacy for molecular testing, sample quality, and safety. RESULTS: Diagnostic yield for histopathologic examination was 87.5% and 83.9% for 19g and 22g respectively (P = 0.625). There was no significant difference in diagnostic yield by cytologic examination based on needle size. There was no significant difference in slide quality. Molecular adequacy for core-biopsy was 77% and 80% for 22g and 19g needles, respectively. Molecular adequacy for cytology cell block was 77% and 80% for 22g and 19g needles, respectively. There were no significant procedural complications. CONCLUSION: Both the 22g and 19g EBUS TBNA needles provided a similar diagnostic yield and clinical utility for ancillary testing. Processing techniques by cytologic methods or "core biopsy" showed no significant impact in diagnostic yield or utility of molecular testing.

Absence of Pathological Proof of Cancer Associated with Improved Outcomes in Early-Stage Lung Cancer.

OBJECTIVES: The purpose of this study was to assess the trends in use of clinical diagnosis and its impact on treatment outcomes in patients receiving radiation therapy for early-stage lung cancer. METHODS: The Surveillance, Epidemiology, and End Results registry was queried from 2004 to 2012 for patients at least 18 years old in whom stage I (clinical stage T1a-T2a) lung cancer had been diagnosed and who underwent radiation therapy alone. Trends in diagnostic confirmation patterns were characterized. A Cox proportional hazards model was used to assess overall survival, and competing risk regression analysis was used to assess cancer-specific survival (CSS). RESULTS: A total of 7050 patients were included; the disease of 6399 of them (90.8%) was pathologically diagnosed and that of 651 (9.2%) was clinically diagnosed. There was no significant change in the utilization of clinical versus pathologic diagnosis (p = 0.172) over time. Patients with T1 disease (p < 0.001), tumors 0 to 1.9 cm in size (p < 0.001), and upper lobe tumors (p = 0.004) were more likely to have been clinically diagnosed. On multivariable analysis, clinical diagnosis was associated with an improved CSS (hazard ratio [HR] = 0.82, 95% confidence interval [CI]: 0.71-0.96) but was not associated with an improved overall survival (HR = 1.01, 95% CI: 0.90-1.13). When stratified by T stage, patients whose disease had been clinically diagnosed as stage T1a had an improved CSS (HR = 0.75, 95% CI: 0.58-0.96, p = 0.022). There was a trend toward improved CSS in patients with clinical stage T1b tumors (HR = 0.74, 95% CI: 0.55-1.00, p = 0.052). CONCLUSIONS: The improved CSS in patients with a clinical diagnosis suggests treatment of benign disease, particularly in smaller tumors. Prudent patient selection is needed to reduce the potential for overtreatment.

ULTRASTRUCTURE OF AUXIN-INDUCED TUMORS OF THE COLEORHIZA-EPIBLAST OF WHEAT.

When wheat is germinated in high concentrations of certain auxins, the coleorhiza-epiblast grows in an excessive and disorganized manner and resembles a callus. Wheat was germinated in 10-3 M indoleacetic acid or in water. There was greater net synthesis of DNA, RNA, and protein in the tumor tissue than in control tissue. Control and tumor tissue was fixed for electron microscopy 1, 2, 3, and 4 days after sowing. In contrast to the controls, many more lipoidal bodies appeared in 1-day-old, auxin-treated tissue and thereafter diminished in number. In 2- and 3-day-old tumor tissue, small membraneous fragments were prominent but disappeared in older tissue. With time, the following changes became progressively more pronounced: cytoplasmic vacuolation, appearance of myelin figures, polyribosome configurations and extensive profiles of rough endoplasmic reticulum, and sloughing of cytoplasmic contents into and accumulation of electron-dense material in vacuoles. Possible factors in susceptibility of certain tissues to tumor formation are discussed.