Robotic-Assisted Navigation Bronchoscopy as a Paradigm Shift in Peripheral Lung Access.

INTRODUCTION: The sensitivity of suspicious lung nodules biopsied by currently available techniques is suboptimal. Robotic-assisted navigation bronchoscopy (RANB) is a novel method for biopsying lung nodules. Our study objective was to determine the sensitivity for malignancy and overall diagnostic accuracy for RANB when combined with cone beam CT (CBCT) for secondary confirmation. METHODS: 52 consecutive patients were prospectively enrolled. Demographic data, nodule characteristics, procedural information, and follow-up results were obtained. RESULTS: Mean patient age was 66, with the majority Caucasian (73%) females (65%) with a similar number of never (46%) and former (46%) smokers. 15 patients had a history of cancer and 3 had a prior thoracic surgery. 59 total nodules were included as 7 patients had two nodules biopsied. Mean nodule diameter was < 2 cm in all dimension with the majority solid (41, 70%) and located in the upper lobes (left: 22, 37%; right: 17, 29%). Bronchus sign was absent (32, 54%) or present (27, 46%) in a similar number. All nodules were successfully reached with nine (15%) requiring minor directional changes after initial cone beam CT. A tissue diagnosis was obtained in 83% (49/59) of biopsied nodules, with malignancy (31, 65%) most common. Including all biopsy results and follow-up imaging, we obtained an 84% (31/37) procedural sensitivity for malignancy and an overall 86% (51/59) diagnostic yield. CONCLUSION: RANB with CBCT increases sensitivity for malignancy and diagnostic accuracy of lung nodule biopsies. Combining these modalities has the potential to shift the diagnostic approach to pulmonary nodules.

Pulmonary gangliocytic paraganglioma: An under-recognized mimic of carcinoid tumor.

Gangliocytic paragangliomas are rare neoplasms occurring almost exclusively in the ampullary region of the gastrointestinal tract. Although these tumors are not typically considered in the differential diagnosis of primary pulmonary neoplasia, 5 cases of primary pulmonary gangliocytic paragangliomas have been previously reported. Herein we report our experience with 3 additional examples, all referred to our Anatomic Pathology Consultation service. The patients (a 32-year-old man, a 69-year-old woman and a 55-year-old man) each presented with an endobronchial (2 cases) or upper lobe lung mass, ranging from 1.5 to 2.5 cm in maximum dimension. Biopsy and endobronchial debulking specimens demonstrated the classic triphasic morphology of gangliocytic paraganglioma, with epithelial, spindled and ganglion-like cells. By immunohistochemistry, the tumors were positive for keratin, synaptophysin and chromogranin A in the epithelial component, S100 protein and glial fibrillary acidic protein (GFAP) in the Schwannian spindled cells, and synaptophysin in ganglion cells. TTF1 expression was seen in the epithelial components of 2 cases. The Ki-67 labelling index was low (<2%). Primary pulmonary gangliocytic paragangliomas should be distinguished from carcinoid tumors, given the different natural histories and risk stratification approaches for these morphologically similar tumors. Awareness that gangliocytic paraganglioma may occur in the lung and appropriate immunohistochemical studies are key to correct diagnosis.

The Pearls and Pitfalls of a Migrating Bullet Embolus.

Venous bullet embolism is an exceedingly rare trauma diagnosis that presents diagnostic and therapeutic challenges. We present the case of a 32-year-old man who sustained multiple gunshot wounds with a venous bullet embolism to the right pulmonary artery. Imaging at first demonstrated a bullet lodged within the right lower lobe. The patient underwent multiple bronchoscopies and ultimately was found to have a bullet embolus in the right pulmonary artery. Repeat endovascular attempts failed at removal, and during a right thoracotomy, the bullet migrated to the left pulmonary artery. Coil embolization of the left lower lobe pulmonary artery was performed, and the patient was found to be asymptomatic at the 1-year follow-up. To our knowledge, this is the first case to demonstrate coil embolization of the pulmonary artery as a method of endovascular treatment for a venous bullet embolus. We present this case report to emphasize the difficulty in diagnosis, localization, and management of a migratory bullet within the pulmonary circulation.