Intraoperative assessment of nodal staging at thoracotomy for carcinoma of the bronchus.

In the staging of operable carcinoma of the bronchus, accurate assessment of mediastinal nodal status is essential in order to determine the feasibility and desirability of resection. In the UK, frozen section analysis is often logistically difficult, and many surgeons rely upon naked-eye assessment. To evaluate the accuracy of this approach, we have reviewed 100 thoracotomies performed for cancer in this unit and compared the naked-eye assessment of nodal staging with the ultimate histological findings. A total of 287 lymph nodes were examined. There were 14 false positives and 10 false negatives. The overall accuracy of naked-eye assessment was 96.1%. On no occasion did an error in naked-eye assessment result in a patient receiving inappropriate treatment. All patients were thought to be pTNM N0 or N1 prior to surgery, yet N2 disease was established in 24 patients. The value of routine mediastinal node dissection at the time of thoracotomy has been established and an important subgroup of patients with microscopic N2 disease has been identified.