contributed equally to this manuscript. but outcome was different depending on histological findings. FEV1 significantly improved in LB patients compared with CBO patients. Survivals at 1 and 3 years were 77% 12% and 60% 14% for patients with CBO and 91% 9% for patients with LB (value of .01 was considered to be statistically significant. For other analyses, a 2-sided value of .05 was considered statistically significant. Analyses were performed using IBM SPSS version 19 (IBM, Armonk, NY). Results Patient Characteristics During the last nearly 30 years, surgical lung resections have been regularly performed at our center in hematologic patients in neutropenia or posttransplantation. In earlier years, the main reason for lung resections was fungal infection [27]. Since 2003, the majority of surgical lung resections in patients after allogeneic HSCT (ie, in 45 of 59 patients) have been Foxd1 for diagnostic SCH 442416 reasons, SCH 442416 early or late after transplantation. Diagnostic questions depended on the time posttransplantation and clinical characteristics. Twenty-seven biopsies were performed to diagnose or exclude BO, which, during this?time period, comprised 90% of all patients in whom BO was suspected based on the criteria described. Three patients did not proceed to VATS because of either patient deferral (n?= 2) or lung reserve was considered too poor (n?= 1). Biopsies in 6 SCH 442416 more patients were performed for suspicion of BO between 1989 and 2002, representing about 30% of all patients who would have qualified for this procedure during that time period. Exact reasons for not undergoing lung biopsy could not be ascertained in all cases, but included both medical reasons (comorbidities, lung function was considered too poor to allow lung surgery with acceptable risk) and patient refusal. Hence, 33 patients for whom a lung biopsy was performed because of an initial suspicion of BO were identified. Ten (30%) had histologically proven CBO; 4 (12%) had CBOi (one with PIV, 3 with RSV); 9 (27%) had LB; and 2 (6%) had LB with concomitant infection (PIV and RSV, one each). In one patient, both CBO and LB lesions were identified. Assuming that the constrictive lesions would be primarily determining for the further course of the disease, this patient was included in our CBO group for further analysis. In the remaining 8 patients (24%), other histological diagnoses were made, including mucus plugging (n?= 4), organizing pneumonia (n?= 2), veno-occlusive disease of the lung, and fibrosis (n?= 1 each). Patient and disease characteristics are shown in Table?1 . Table?1 Patient, Disease, and Transplant Characteristics The authors reported no potential conflicts of interest. A.H., T.L., J.P.H., and M.T. designed the study and drafted the manuscript. A.H., T.L., and S.G. collected the data; A.H., T.L., and M.S. did the statistical analysis; F.G. and D.L. performed the lung biopsies; L.B. and S.S. evaluated the biopsies; and P.G. and M.T. analyzed PFT and performed BAL. All authors contributed to data analysis, data interpretation and writing of the manuscript. A.H. and T.L. contributed equally to this manuscript. M.T. and J.P.H. contributed equally to this manuscript. The authors have nothing to disclose. Footnotes See Acknowledgments on page 979..