🎯 Background & Rationale
While traditional rapid on-site evaluation (ROSE) of cytopathology is well-established for mediastinal staging via endobronchial ultrasound (EBUS), its role in evaluating peripheral pulmonary lesions (PPLs) remains challenging and less standardized. Traditional ROSE requires a cytopathologist or cytotechnician, relies on touch-imprint cytology or smears, and suffers from logistical and time constraints. This study addresses the clinical gap of achieving real-time, intraprocedural confirmation of representative tissue acquisition for PPLs by introducing proceduralist-directed Rapid On-Site Pathologic Evaluation (ROPE) using Dynamic Cell Imaging (DCI). By leveraging the Warburg effect (cellular metabolic activity), DCI permits the proceduralist to evaluate intact tissue specimens (cryobiopsies and forceps biopsies) directly at the point of care without complex slide preparation.
👥 Study Design & Population
This is a single-center pilot study evaluating 50 consecutive patients undergoing robotic-assisted bronchoscopy with radial probe EBUS for the sampling of PPLs.
- Population: 50 patients (60% male, median age 71 years) with a total of 146 biopsy samples (comprising 21G fine needle aspirations, cryobiopsies, and forceps biopsies).
- Intervention: Proceduralist-directed ROPE using the DCI (Van Gogh/CelTivity) system to assess tissue samples as either “lesional” or “nonlesional” in real time.
- Comparator / Gold Standard: Final histopathologic and cytopathologic diagnosis determined by a blinded pathologist, classifying samples as diagnostic (malignant or specific benign) or nondiagnostic.
📈 Methodology & Rigor
The study prospectively collected samples in a standardized sequence (FNA, cryobiopsy, forceps biopsy, brushes, BAL). The proceduralists underwent a brief training protocol (5 supervised procedures) to learn DCI interpretation. Concordance between the proceduralist’s DCI assessment and the pathologist’s final diagnosis was calculated at both the patient level and the biopsy level, stratified by tissue acquisition technique and final pathologic diagnosis. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using bootstrap methods to account for clustered biopsies within individuals. As a pilot study, the sample size was not based on formal power calculations.
🔬 Key Findings [or Planned Endpoints]
- Patient-Level Concordance: Overall concordance between the proceduralist’s DCI interpretation and the pathologist’s final diagnosis was 88%.
- Biopsy-Level Concordance: Overall concordance across all 146 individual biopsies was 84% (95% CI: 77%–90%).
- Stratification by Technique: Concordance was highest for cryobiopsy at 88% and forceps biopsy at 86%, while FNA demonstrated the lowest concordance at 79%. Cryobiopsy specimens showed the highest sensitivity (98%) and positive predictive value.
- Pathology Yield: The cohort achieved a 74% conclusive final diagnosis rate (44% malignant, 32% specific benign, 21% inconclusive). Notably, of the 4 patients deemed inconclusive initially who were later diagnosed with malignancy on follow-up, all had at least one sample identified as lesional by DCI.
- Procedural Efficiency: Median procedure time was 35 minutes and 8 seconds, with no workflow delays reported. Complications included 4 cases of pneumothorax (8%) and 4 cases of grade 2 bleeding (8%).
⚖️ Critical Appraisal
Internal Validity & Strengths: The study boasts a rigorous, consecutive inclusion of all eligible patients without prescreening, minimizing selection bias. It directly evaluates advanced tissue-handling tools (cryoprobes) that align with modern interventional pulmonology trends.
Limitations: The trial is limited by its single-center design, small sample size, and execution by only two experienced proceduralists, which limits generalizability. Furthermore, cryobiopsies demonstrated a low specificity (19%), likely because DCI detects metabolic activity in non-neoplastic, reactive, or fibrotic tissue (false positives). Larger, multi-center trials with multiple operators are necessary to confirm reproducibility and evaluate true impacts on overall diagnostic yield.
💡 The Clinical Bottom Line
Proceduralist-directed ROPE using Dynamic Cell Imaging (DCI) is a feasible, rapid, point-of-care tool that shows high concordance with final pathology, particularly when paired with cryobiopsy and forceps biopsy. While it does not replace formal pathology, it successfully provides real-time intraprocedural feedback, boosting proceduralist confidence that representative diagnostic tissue has been successfully procured. Clinicians can view DCI as an emerging bridge to improve intraprocedural efficiency—and potentially enhance target localization—in advanced navigational bronchoscopy suites.