Immune aging: biological mechanisms, clinical symptoms, and management in lung transplant recipients.

While chronologic age can be precisely defined, clinical manifestations of advanced age occur in different ways and at different rates across individuals. The observed phenotype of advanced age likely reflects a superposition of several biological aging mechanisms which have gained increasing attention as the world contends with an aging population. Even within the immune system, there are multiple age-associated biological mechanisms at play, including telomere dysfunction, epigenetic dysregulation, immune senescence programs, and mitochondrial dysfunction. These biological mechanisms have associated clinical syndromes, such as telomere dysfunction leading to short telomere syndrome (STS), and optimal patient management may require recognition of biologically based aging syndromes. Within the clinical context of lung transplantation, select immune aging mechanisms are particularly pronounced. Indeed, STS is increasingly recognized as an indication for lung transplantation. At the same time, common aging phenotypes may be evoked by the stress of transplantation because lung allografts face a potent immune response, necessitating higher levels of immune suppression and associated toxicities, relative to other solid organs. Age-associated conditions exacerbated by lung transplant include bone marrow suppression, herpes viral infections, liver cirrhosis, hypogammaglobulinemia, frailty, and cancer risk. This review aims to dissect the molecular mechanisms of immune aging and describe their clinical manifestations in the context of lung transplantation. While these mechanisms are more likely to manifest in the context of lung transplantation, this mechanism-based approach to clinical syndromes of immune aging has broad relevance to geriatric medicine.

Anti-fibrotic therapy and lung transplant outcomes in patients with idiopathic pulmonary fibrosis.

BACKGROUND: It is unclear whether continuing anti-fibrotic therapy until the time of lung transplant increases the risk of complications in patients with idiopathic pulmonary fibrosis. OBJECTIVES: To investigate whether the time between discontinuation of anti-fibrotic therapy and lung transplant in patients with idiopathic pulmonary fibrosis affects the risk of complications. METHODS: We assessed intra-operative and post-transplant complications among patients with idiopathic pulmonary fibrosis who underwent lung transplant and had been treated with nintedanib or pirfenidone continuously for ⩾ 90 days at listing. Patients were grouped according to whether they had a shorter (⩽ 5 medication half-lives) or longer (> 5 medication half-lives) time between discontinuation of anti-fibrotic medication and transplant. Five half-lives corresponded to 2 days for nintedanib and 1 day for pirfenidone. RESULTS: Among patients taking nintedanib (n = 107) or pirfenidone (n = 190), 211 (71.0%) had discontinued anti-fibrotic therapy ⩽ 5 medication half-lives before transplant. Anastomotic and sternal dehiscence occurred only in this group (anastomotic: 11 patients [5.2%], p = 0.031 vs patients with longer time between discontinuation of anti-fibrotic medication and transplant; sternal: 12 patients [5.7%], p = 0.024). No differences were observed in surgical wound dehiscence, length of hospital stay, or survival to discharge between groups with a shorter versus longer time between discontinuation of anti-fibrotic therapy and transplant. CONCLUSION: Anastomotic and sternal dehiscence only occurred in patients with idiopathic pulmonary fibrosis who discontinued anti-fibrotic therapy < 5 medication half-lives before transplant. The frequency of other intra-operative and post-transplant complications did not appear to differ depending on when anti-fibrotic therapy was discontinued. REGISTRATION: clinicaltrials.gov NCT04316780: https://clinicaltrials.gov/ct2/show/NCT04316780.

Effect of donor smoking and substance use on post-lung transplant outcomes.

OBJECTIVE: The study objective was to determine effects of donor smoking and substance use on primary graft dysfunction, allograft function, and survival after lung transplant. METHODS: From January 2007 to February 2020, 1366 lung transplants from 1291 donors were performed in 1352 recipients at Cleveland Clinic. Donor smoking and substance use history were extracted from the Uniform Donor Risk Assessment Interview and medical records. End points were post-transplant primary graft dysfunction, longitudinal forced expiratory volume in 1 second (% of predicted), and survival. RESULTS: Among lung transplant recipients, 670 (49%) received an organ from a donor smoker, 163 (25%) received an organ from a donor with a 20 pack-year or more history (median pack-years 8), and 702 received an organ from a donor with substance use (51%). There was no association of donor smoking, pack-years, or substance use with primary graft dysfunction (P > .2). Post-transplant forced expiratory volume in 1 second was 74% at 1 year in donor nonsmoker recipients and 70% in donor smoker recipients (P = .0002), confined to double-lung transplant, where forced expiratory volume in 1 second was 77% in donor nonsmoker recipients and 73% in donor smoker recipients. Donor substance use was not associated with allograft function. Donor smoking was associated with 54% non-risk-adjusted 5-year survival versus 59% (P = .09) and greater pack-years with slightly worse risk-adjusted long-term survival (P = .01). Donor substance use was not associated with any outcome (P ≥ 8). CONCLUSIONS: Among well-selected organs, lungs from smokers were associated with non-clinically important worse allograft outcomes without an inflection point for donor smoking pack-years. Substance use was not associated with worse allograft function. Given the paucity of organs, donor smoking or substance use alone should not preclude assessment for lung donation or transplant.

Reflux Surgery in Lung Transplantation: A Multicenter Retrospective Study.

BACKGROUND: Aspiration has been associated with graft dysfunction after lung transplantation, leading some to advocate for selective use of fundoplication despite minimal data supporting this practice. METHODS: We performed a multicenter retrospective study at 4 academic lung transplant centers to determine the association of gastroesophageal reflux disease and fundoplication with bronchiolitis obliterans syndrome and survival using Cox multivariable regression. RESULTS: Of 542 patients, 136 (25.1%) underwent fundoplication; 99 (18%) were found to have reflux disease without undergoing fundoplication. Blanking the first year after transplantation, fundoplication was not associated with a benefit regarding freedom from bronchiolitis obliterans syndrome (hazard ratio [HR], 0.93; 95% CI, 0.58-1.49) or death (HR, 0.97; 95% CI, 0.47-1.99) compared with reflux disease without fundoplication. However, a time-dependent adjusted analysis found a slight decrease in mortality (HR, 0.59; 95% CI, 0.28-1.23; P = .157), bronchiolitis obliterans syndrome (HR, 0.68; 95% CI, 0.42-1.11; P = .126), and combined bronchiolitis obliterans syndrome or death (HR, 0.66; 95% CI, 0.42-1.04; P = .073) in the fundoplication group compared with the gastroesophageal reflux disease group. CONCLUSIONS: Although a statistically significant benefit from fundoplication was not determined because of limited sample size, follow-up, and potential for selection bias, a randomized, prospective study is still warranted.

Infectious Complications in Lung Transplant Recipients.

Infection remains a common cause of death throughout the lifespan of a lung transplant recipient. The increased susceptibility of lung transplant recipients is multifactorial including exposure of the graft to the external environment, impaired mucociliary clearance, and high levels of immunosuppression. Long-term outcomes in lung transplant recipients remain poor compared with other solid organ transplants largely due to deaths from infections and chronic allograft dysfunction. Antibacterial, antifungal, and antiviral prophylaxis may be used after lung transplantation to target a number of different opportunistic infections for varying durations of time. The first-month posttransplant is most commonly characterized by nosocomial infections and donor-derived infections. Following the first month to the first 6 months after transplant-a period of intense immunosuppression-is associated with opportunistic infections. While immunosuppression is reduced after the first year posttransplant, infection remains a risk with community-acquired and rarer infectious agents. Clinicians should be vigilant for infection at all time points after transplant. The use of patient-tailored prophylaxis and treatments help ensure graft and patient survival.

Intragraft Hyaluronan Increases in Association With Acute Lung Transplant Rejection.

BACKGROUND: Acute perivascular rejection (AR) is common in lung recipients and increases the risk for chronic lung allograft dysfunction (CLAD). Hyaluronan (HA), an extracellular matrix constituent, accumulates in experimental AR and can act as an innate immune agonist, breaking tolerance and potentiating alloimmunity. We previously demonstrated HA accumulates in CLAD after human-lung transplantation. We sought to determine if HA accumulates in the bronchoalveolar lavage fluid (BALF) concurrent with AR in lung recipients. METHODS: The cohort consisted of 126 first adult lung recipients at 5 transplant centers with a total of 373 BALF samples collected within the first posttransplant year. All samples were paired with a lung biopsy from the same bronchoscopy. BALF HA (ng/mL) was quantified by ELISA and log-transformed for analysis. Linear-mixed effect models, adjusted for potential confounders, were used to estimate the association between BALF HA concentration and the presence of AR on biopsy. The association between early posttransplant BALF HA levels and the development of CLAD was explored utilizing tertiles of maximum BALF HA level observed within the first 6 months of transplant. RESULTS: In analyses adjusted for potential confounders, BALF HA concentration was significantly increased in association with AR (change in means on log-scale 0.31; 95% CI, 0.01-0.60; P = 0.044). When considered on the original scale (ng/mL), BALF HA concentrations were 1.36 times (36%) higher, on average, among samples with, versus without, AR. The cumulative incidence of CLAD was numerically higher in individuals in the highest tertiles of BALF HA level within the first 6 months after transplant, as compared with those in the lowest tertile; however, this difference was not statistically significant (P = 0.32). CONCLUSIONS: These results demonstrate accumulation of HA in clinical AR and suggest a mechanism by which innate and adaptive immune activation might interact in the development of AR and CLAD.

Pleural space management after lung transplant: Early and late outcomes of pleural decortication.

BACKGROUND: Pleural complications after lung transplant may restrict allograft expansion, requiring decortication. However, its extent, indications, risk factors, and effect on allograft function and survival are unclear. METHODS: From January 2006 to January 2017, 1,039 patients underwent primary lung transplant and 468 had pleural complications, 77 (16%) of whom underwent 84 surgical decortications for pleural space management. Multivariable time-related analysis was performed to identify risk factors for decortication. Mixed-effect longitudinal modeling was used to assess allograft function before and after decortication. RESULTS: Cumulative number of decortications per 100 transplants was 1.8, 7.8, and 8.8 at 1 month, 1 year, and 3 years after transplant, respectively. Indications for the 84 decortications were complex effusion in 47 (56%), fibrothorax in 17 (20%), empyema in 11 (13%), and hemothorax in 9 (11%). Thoracoscopic operations were performed in 52 (62%) and full lung re-expansion was achieved in 76 (90%). Complications occurred after 30 (36%) decortications, with 15 pulmonary complications (18%), including 2 patients requiring extracorporeal support due to worsening function. Ten reinterventions occurred via thoracentesis (2), tube thoracostomy (1), and reoperation (7). In-hospital and 30-day mortality was 5.2% (n = 4/77). Forced expiratory volume in 1 second increased from 50% to 60% within the first year after decortication, followed by a slow decline to 55% at 5 years. Postdecortication survival was 87%, 68%, and 48% at 1, 3, and 5 years, respectively. CONCLUSIONS: Despite high risk of reoperative surgery, decortication after lung transplant allows salvage of pleural space and graft function with a reasonable morbidity profile.

Correlation between BAL CXCR3 chemokines and lung allograft histopathologies: A multicenter study.

The histopathologic diagnosis of acute allograft injury is prognostically important in lung transplantation with evidence demonstrating a strong and consistent association between acute rejection (AR), acute lung injury (ALI), and the subsequent development of chronic lung allograft dysfunction (CLAD). The pathogenesis of these allograft injuries, however, remains poorly understood. CXCL9 and CXCL10 are CXC chemokines induced by interferon-γ and act as potent chemoattractants of mononuclear cells. We hypothesized that these chemokines are involved in the mononuclear cell recruitment associated with AR and ALI. We further hypothesized that the increased activity of these chemokines could be quantified as increased levels in the bronchoalveolar lavage fluid. In this prospective multicenter study, we evaluate the incidence of histopathologic allograft injury development during the first-year post-transplant and measure bronchoalveolar CXCL9 and CXCL10 levels at the time of the biopsy. In multivariable models, CXCL9 levels were 1.7-fold and 2.1-fold higher during AR and ALI compared with "normal" biopsies without histopathology. Similarly, CXCL10 levels were 1.6-fold and 2.2-fold higher during these histopathologies, respectively. These findings support the association of CXCL9 and CXCL10 with episodes of AR and ALI and provide potential insight into the pathogenesis of these deleterious events.

Natural History of Pleural Complications After Lung Transplantation.

BACKGROUND: Despite advances in lung transplantation, 5-year survival remains at 56%. Although the focus has been on chronic lung allograft dysfunction and infection, pleural complications in some may contribute to adverse outcomes. Therefore, we determined (1) the prevalence of, and risk factors for, pleural complications after lung transplantation and (2) their association with allograft function and mortality. METHODS: From 2006 to 2017, 1039 adults underwent primary lung transplantation at Cleveland Clinic in Cleveland, Ohio. Multivariable analyses were performed in the multiphase mixed longitudinal and hazard function domains to identify risk factors associated with allograft function and survival. RESULTS: A total of 468 patients (45%) had pleural complications, including pleural effusion in 271 (26%), pneumothorax in 152 (15%), hemothorax in 128 (12%), empyema in 47 (5%), and chylothorax in 9 (1%). Risk factors for pleural complications within the first 3 months included higher recipient-to-donor weight ratio, lower recipient albumin, and recipient-to-donor race mismatch; risk factors extending beyond 3 months included older age, hypertension, smoking history, lower lung allocation score, and donor death from anoxia. Cardiopulmonary bypass and previous thoracic interventions were not risk factors in patients with pleural effusions who were treated with thoracentesis only, and forced expiratory volume in 1 second improved after drainage; however, repeat percutaneous or surgical interventions did not impart a similar benefit. Pleural complications were associated with worse survival. CONCLUSIONS: Pleural complications are common after lung transplantation and are associated with worse allograft function and survival. These complications are likely secondary to other underlying clinical problems. Malnourishment and size mismatch are modifiable risk factors.

Bronchoalveolar bile acid and inflammatory markers to identify high-risk lung transplant recipients with reflux and microaspiration.

BACKGROUND: Gastroesophageal reflux disease (GERD) is a risk factor for chronic lung allograft dysfunction. Bile acids-putative markers of gastric microaspiration-and inflammatory proteins in the bronchoalveolar lavage (BAL) have been associated with chronic lung allograft dysfunction, but their relationship with GERD remains unclear. Although GERD is thought to drive chronic microaspiration, the selection of patients for anti-reflux surgery lacks precision. This multicenter study aimed to test the association of BAL bile acids with GERD, lung inflammation, allograft function, and anti-reflux surgery. METHODS: We analyzed BAL obtained during the first post-transplant year from a retrospective cohort of patients with and without GERD, as well as BAL obtained before and after Nissen fundoplication anti-reflux surgery from a separate cohort. Levels of taurocholic acid (TCA), glycocholic acid, and cholic acid were measured using mass spectrometry. Protein markers of inflammation and injury were measured using multiplex assay and enzyme-linked immunosorbent assay. RESULTS: At 3 months after transplantation, TCA, IL-1ß, IL-12p70, and CCL5 were higher in the BAL of patients with GERD than in that of no-GERD controls. Elevated TCA and glycocholic acid were associated with concurrent acute lung allograft dysfunction and inflammatory proteins. The BAL obtained after anti-reflux surgery contained reduced TCA and inflammatory proteins compared with that obtained before anti-reflux surgery. CONCLUSIONS: Targeted monitoring of TCA and selected inflammatory proteins may be useful in lung transplant recipients with suspected reflux and microaspiration to support diagnosis and guide therapy. Patients with elevated biomarker levels may benefit most from anti-reflux surgery to reduce microaspiration and allograft inflammation.

Risk Factors for Acute Rejection in the First Year after Lung Transplant. A Multicenter Study.

Rationale: Acute rejection, manifesting as lymphocytic inflammation in a perivascular (acute perivascular rejection [AR]) or peribronchiolar (lymphocytic bronchiolitis [LB]) distribution, is common in lung transplant recipients and increases the risk for chronic graft dysfunction.Objectives: To evaluate clinical factors associated with biopsy-proven acute rejection during the first post-transplant year in a present-day, five-center lung transplant cohort.Methods: We analyzed prospective diagnoses of AR and LB from over 2,000 lung biopsies in 400 newly transplanted adult lung recipients. Because LB without simultaneous AR was rare, our analyses focused on risk factors for AR. Multivariable Cox proportional hazards models were used to assess donor and recipient factors associated with the time to the first AR occurrence.Measurements and Main Results: During the first post-transplant year, 53.3% of patients experienced at least one AR episode. Multivariable proportional hazards analyses accounting for enrolling center effects identified four or more HLA mismatches (hazard ratio [HR], 2.06; P ≤ 0.01) as associated with increased AR hazards, whereas bilateral transplantation (HR, 0.57; P ≤ 0.01) was associated with protection from AR. In addition, Wilcoxon rank-sum analyses demonstrated bilateral (vs. single) lung recipients, and those with fewer than four (vs. more than four) HLA mismatches demonstrated reduced AR frequency and/or severity during the first post-transplant year.Conclusions: We found a high incidence of AR in a contemporary multicenter lung transplant cohort undergoing consistent biopsy sampling. Although not previously recognized, the finding of reduced AR in bilateral lung recipients is intriguing, warranting replication and mechanistic exploration.

Utilization of Marginal Lung Donors With Low PaO2/FiO2 Ratio and High Body Mass Index.

BACKGROUND: Lungs of donors with high body mass index (BMI) have more atelectasis and a lower PaO2/FiO2 (P/F) ratio than those with normal BMI. This study prospectively evaluated outcomes of a new approach for these lungs in our lung transplant program. METHODS: From February 2016 to December 2018, 336 lung transplants were performed at Cleveland Clinic. Of these, 58 met criteria for our aggressive approach to donors with a P/F ratio of less than 300 mm Hg at offer and BMI of 25 kg/m2 or greater. In the donor operating room, lung recruitment was performed by positive end-respiratory pressure of 25 to 30 cmH2O for 30 seconds and lungs were converted to either straight transplantation or ex vivo lung perfusion (EVLP). Postoperative outcomes of the low P/F-high BMI group were compared with those of recipients receiving lungs meeting standard criteria. RESULTS: Of the 58 donors, 33 were converted to straight lung transplantation because they demonstrated significant improvement in the P/F ratio after lung recruitment compared with the P/F ratio at lung offer (median, 278 versus 420 mm Hg; P < .01). Seventeen lungs with a persistently low P/F ratio underwent EVLP, 8 of which were transplanted. There was no significant difference in primary graft dysfunction grade 3 at 72 hours (n = 3 of 41 [7.5%] versus 31 of 247 [13%]; P = .79) or in 30-day survival (100% versus 97%; P = .60) between low P/F-high BMI and standard groups. CONCLUSIONS: These data suggest that atelectasis in high-BMI donors contributes to P/F ratios less than 300 mm Hg and that intraoperative lung recruitment or EVLP can allow the use of lungs from these donors with good outcomes.

Lung Transplant for Patient With Idiopathic Pneumonia Syndrome.

Idiopathic pneumonia syndrome (IPS) is a serious complication after hematopoietic stem cell transplantation. Despite the high mortality rate with medical management, there have been no reported cases of lung transplants for patients with IPS. We report a case involving a 44-year-old woman who developed IPS 5 months after hematopoietic stem cell transplantation for myelodysplastic syndrome. Despite aggressive medical management, the patient required intubation and was administered extracorporeal membrane oxygenation while awaiting recovery. However, her condition continued to deteriorate, and she subsequently underwent a double lung transplant with uneventful recovery. With the high mortality of medically managed IPS, lung transplant could prove to be lifesaving.

Consequences of Delayed Chest Closure During Lung Transplantation.

BACKGROUND: Delayed chest closure is commonly used for cardiac surgery. However, insufficient data exist to guide its management in immunosuppressed lung transplantation patients, with unclear long-term consequences. METHODS: We performed 769 lung transplantations between January 2009 and January 2016. Of these, 47 (6%) required delayed chest closure because of coagulopathy, respiratory intolerance, and hemodynamic instability. On multivariable analysis, risk factors for delayed chest closure included double-lung transplantation and longer ischemic times. To account for differences between the 2 groups, we performed propensity matching, generating 46 well-matched pairs. RESULTS: Among matched patients with appropriate antimicrobial prophylaxis, we found no difference in 30-day prevalence of pneumonia, empyema, Clostridium difficile, bloodstream, and deep wound infections. There was also no difference in 6-month composite infections. However, delayed chest closure patients received more transfusions within 5 days of transplantation (median, 7 vs 3 units; P < .001), had more intubations > 5 days (80% vs 41%, P < .001), had more severe primary graft dysfunction (39% vs 17%, P = .044), had a longer hospital stay (median, 61 vs 25 days; P < .001), and had worse pulmonary function tests 6 years after transplant (P = .019). Fortunately, estimated survival at 6 months, 1 year, and 5 years between delayed and primary chest closure groups was similar (82%, 76%, and 39% vs 84%, 75%, and 50%, respectively; P = .23). CONCLUSIONS: Use of delayed chest closure does not yield more infections or worse long-term survival. However it may be associated with increased in-hospital morbidities and worse long-term pulmonary function.

Usefulness of gene expression profiling of bronchoalveolar lavage cells in acute lung allograft rejection.

BACKGROUND: Chronic lung allograft dysfunction (CLAD) is the main limitation to long-term survival after lung transplantation. Because effective therapies are lacking, early identification and mitigation of risk factors is a pragmatic approach to improve outcomes. Acute cellular rejection (ACR) is the most pervasive risk factor for CLAD, but diagnosis requires transbronchial biopsy, which carries risks. We hypothesized that gene expression in the bronchoalveolar lavage (BAL) cell pellet (CP) could replace biopsy and inform on mechanisms of CLAD. METHODS: We performed RNA sequencing on BAL CPs from 219 lung transplant recipients with A-grade ACR (n = 61), lymphocytic bronchiolitis (n = 58), infection (n = 41), or no rejection/infection (n = 59). Differential gene expression was based on absolute fold difference >2.0 and Benjamini-adjusted p-value ≤0.05. We used the Database for Annotation, Visualization and Integrated Discovery Bioinformatics Resource for pathway analyses. For classifier modeling, samples were randomly split into training (n = 154) and testing sets (n = 65). A logistic regression model using recursive feature elimination and 5-fold cross-validation was trained to optimize area under the curve (AUC). RESULTS: Differential gene expression identified 72 genes. Enriched pathways included T-cell receptor signaling, natural killer cell-mediated cytotoxicity, and cytokine-cytokine receptor interaction. A 4-gene model (AUC = 0.72) and classification threshold defined in the training set exhibited fair performance in the testing set; accuracy was 76%, specificity 82%, and sensitivity 60%. In addition, classification as ACR was associated with worse CLAD-free survival (hazard ratio = 2.42; 95% confidence interval = 1.29-4.53). CONCLUSIONS: BAL CP gene expression during ACR is enriched for immune response pathways and shows promise as a diagnostic tool for ACR, especially ACR that is a precursor of CLAD.

A single-institution study of concordance of pathological diagnoses for interstitial lung diseases between pre-transplantation surgical lung biopsies and lung explants.

BACKGROUND: By comparing diagnoses made by pre-transplant surgical lung biopsy (SLB) and the final pathologic diagnosis of the explanted pathology (EP), we aimed to study the factors that could impact pathologic diagnoses in patients with interstitial lung disease (ILD). METHODS: We retrospectively reviewed the lung transplant database at Cleveland Clinic [01/01/2006-12/31/2013] to include all lung transplant recipients with a prior diagnosis of ILD. Two pulmonary pathologists independently reviewed each SLB and lung explant. The diagnoses were labeled as concordant (same diagnosis on SLB and explant) or discordant (diagnosis on SLB and explant were different) by consensus. RESULTS: Of 389 patients transplanted for ILD, 217 had an SLB before transplant. Pathological diagnoses were concordant in 190 patients (87.6%) [165 UIP (86.8%), 13 NSIP (6.8%), 8 CHP (4.2%) and 4 other diagnoses (2.1%). In 27 cases (12.4%), the diagnosis on SLB differed from EP. 8/27 were diagnosed with UIP on SLB and of these, 5 were re-classified as NSIP. 14/19 (73.7%) patients with a SLB diagnosis "other than UIP" were re-categorized as UIP based on explant. Discordant cases had a greater time between SLB and EP than concordant cases (1553 days vs 1248 days). CONCLUSIONS: The pathologic diagnosis of ILD by SLB prior to lung transplant is accurate in most patients, but may be misleading in a small subset of patients. The majority of discordant cases that were reclassified as UIP could be due to a sampling error, or perhaps, an increased time from the date of the SLB to transplant. Future studies examining how multidisciplinary consensus diagnosis affects this discordance are necessary.

Patterns of Recurrence and Overall Survival in Incidental Lung Cancer in Explanted Lungs.

BACKGROUND: Recurrence and overall survival for incidental lung cancer in explanted lungs vary between different series. Recurrence patterns are also not well described. The primary objective of this study is to study the recurrence patterns and time to recurrence for various stages of lung cancer in lung transplant recipients. METHODS: A retrospective review of our institutional database was performed to identify patients who had incidental lung cancer found in transplant pneumonectomy specimens from 1990 to 2017. Demographic, radiographic, and perioperative clinical variables were collected. Time to recurrence, overall survival, and recurrence patterns were recorded. Freedom from recurrence and overall survival were estimated by using Kaplan-Meier analysis. RESULTS: Thirty-one patients had unexpected malignancy and 29 patients (1.6%) had primary lung carcinoma in the explanted lung. Indication for transplantation was chronic obstructive pulmonary disease in 15 patients (48%) and interstitial lung disease for 16 patients (52%). Preoperative imaging showed indeterminate nodules in 10 patients (32%). Pathologic review showed stage I disease in 15 patients (54%), stage II disease in 10 patients (35%), and stage III disease in 2 patients (7%). Recurrence was noted in 8 patients (28%). Most patients had nodal disease (25%) or systemic recurrence (75%). All recurrences occurred within 2 years of the transplantation. For patients with stage I and II disease, freedom from recurrence at 1, 3, and 5 years was 91%, 55%, and 55%, respectively. Overall survival at 1, 3, and 5 years was 78%, 18%, and 14%, respectively. CONCLUSIONS: Most recurrences occur within 2 years after transplantation and are the cause of death in these patients. Patients with nodal disease tend to have higher recurrence rates. Multidisciplinary review of abnormal radiographic findings before transplantation and close follow-up may allow for detection of undiagnosed cancers.

Corrigendum to: Post-transplant lymphoproliferative disorder presenting on post-transplant Day 35 as a pulmonary parenchymal infiltrate-a case report.

[This corrects the article DOI: 10.1093/omcr/omy035.][This corrects the article DOI: 10.1093/omcr/omy035.].