s S5 material diagnostic of a benign condition (ex: granulomas) 9%, suspect/ positive for malignancy 32%. Application of Nayak’s criteria decreased OSA to 85% (100/118) with 13 revised cases (11%); all downgraded from “adequate” to “unsatisfactory.” All the original unsatisfactory cases remained unsatisfactory with the new criteria. Comparison of initial and revised OSA, final diagnosis and follow-up is shown in Table 1. Conclusions: Uniformity in OSA and reporting for nodal EBUS TBNA is needed. Nayak’s criteria were readily applicable, yielding 13 (11%) revised cases. Revision did not affect final patient outcome. We would add to the criteria that “nodal elements should be well-visualized and unobscured” and recommend that “atypical” (13% of our series) be added as a diagnostic category if (in addition to adequacy) a preliminary diagnosis is provided at time of on-site evaluation. Prospective studies are needed to further refine these criteria. Table 1 Comparison of initial OSA, revised OSA, final diagnosis, and follow-up for the 13 revised cases after application of OSA criteria proposed by Nayak et al. (1) Patient Site Initial Revised Final Cytologic Follow-up OSA* OSA* Diagnosis (incl. Pap stain and cell block)** 2 4L 1 0 Unsatisfactory (no cell block) Surgical resection for small cell carcinoma; 4L was negative for malignancy 8 7 1 0 Cell block only: Neuroendocrine carcinoma No follow up 12 11L 1 0 Negative No follow up 12 4R 1 0 Negative No follow up 37 4L 1 0 Negative (no cell block) Granulomatous inflammation consistent with sarcoidosis in other nodes 43 12L 1 0 Negative Suspect lesion resolved without treatment 51 2R 1 0 Negative Separate node sampled was positive for malignancy 55 11R 1 0 Negative Lung biopsy: adenocarcinoma 63 4L 1 0 Negative Lung biopsy: lipoid pneumonia 65 11L 1 0 Negative Surgical resection for squamous cell carcinoma. 11L showed granulomatous inflammation 66 4L 1 0 Cell block only: Squamous cell carcinoma No follow up 74 7 1 0 Negative Lung biopsy: squamous cell carcinoma 76 10L 1 0 Negative EBUS repeat: Negative * 1 Z adequate, 0 Z unsatisfactory ** Negative Z benign lymph node (1) Nayak A, Sugrue C, Koenig S, Wasserman P, Hoda S, Morgenstern N, “Endobronchial Ultrasound-Guided Transbronchial Needle Aspirate (EBUS-TBNA): A Proposal for On-Site Adequacy Criteria.” Diagnostic Cytopathology, Vol 40(2): 128-137. 2010.