Objectives: Evaluation of the diagnostic efficiency of the intraoperative cytological examination of lymphatic nodes obtained during transcervical extended mediastinal lymphadenectomy (TEMLA).
Methods: All mediastinal nodes obtained during consecutive TEMLA operations in patients with confirmed lung cancer were examined. Cytological imprints from cross sections of nodes were performed, fixed in 96 proof alcohol and stained with Haematoxylin-Eosin. The cytological slides were evaluated by light microscopy intraoperatively, and a standard paraffin histological examination of the same nodes was done afterwards for confirmation of the final diagnosis.
Results: Intraoperative cytological studies were performed in 63 patients (17 women and 46 men; overall in 453 mediastinal nodal stations) from 1 April 2009 to 28 February 2011. The mean number of nodes/procedure was 27.8. The mean time of performance of the examination was 37 min, including 7 min for smears, 13 min for staining and 17 min for microscopic examination (overall 37 min). The cytological study discovered neoplasmatic cells in 12 of 63 patients, nodal stations in 22 of 453 and nodes in 44 of 1724. According to the analysis of the 63 patients, the imprint cytology technique had a sensitivity of 92.3%, specificity of 100%, accuracy of 98.4%, positive predictive value of 100% and negative predictive value of 98.0%, as was confirmed by the final histopathological examination.
Conclusions: (i) Cytological imprints examination was characterized by a very high specificity and sensitivity, is technically simpler and faster and allows for the examination of several dozens of lymphatic nodes during a single TEMLA procedure within an acceptable time, and after the exclusion of N2 nodes enables the simultaneous performance of a radical lung resection. (ii) The presented technique was the alternative for the traditional histopathological examination of the material frozen in cryostat.