The case reported by Dr Dieter highlights one potential cause of false-positive results—specifically, passing the EBUS-TBNA needle through the node and into an adjacent parenchymal lung tumor. The case description says that both right hilar and right paratracheal lymph nodes demonstrated malignant cells, but the lymph node stations are not specified. Similarly, it says there was a right-sided tumor, but the lobe is not specified, so it is difficult to draw conclusions. It seems most likely, based on the information provided, that the EBUS-TBNA positive lymph nodes were the 10R or 11R and the 4R, and the tumor was in the right upper lobe. If the tumor was in the right upper lobe, adjacent to the trachea, and extended into the area of the right mainstem bronchus and right upper lobe take-off, it is plausible that both 11R and 4R EBUS-TBNA samples could be falsely positive. Alternatively, it might have been only the 4R that was false positive, since the 11R would not have changed the decision on surgery. It is difficult to tell from the description provided. It would be useful to clarify what the findings were that led Dr Dieter and his team to identify the nodes as negative and to recommend surgery. Since review of the prior biopsy showed both lymph nodes and cancer, presumably it was the prior CT scan and PET scan images rather than the cytology results that provided this information. Tumor adjacent to but not directly invading the 4R and/or 10R or 11R lymph nodes might have been identified by CT/PET scan. Additional images would be useful to clarify this. If there was direct extension of the tumor into the 4R region, this would provide supporting evidence that this was indeed a false-positive result.