Can lungs be taken for transplantation from donors with a significant smoking history?

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.

Short- and Long-Term Impact of Smoking Donors in Lung Transplantation: Clinical and Pathological Analysis

BACKGROUND

The use of smoking donors (SD) is one strategy to increase the organ pool for lung transplantation (LT), but the benefit-to-risk ratio has not been demonstrated. This study aimed to evaluate the impact of SD history on recipient outcomes and graft alterations.

METHODS

LTs in 293 patients were retrospectively reviewed and divided into non-SD (n = 225, group I), SD < 20 pack-years (n = 45, group II), and SD ≥ 20 pack-years (n = 23, group III) groups. Moreover, several lung donor biopsies before implantation (equally divided between groups) were evaluated, focusing on smoking-related lesions. Correlations were analyzed between all pathological data and smoking exposure, along with other clinical parameters.

RESULTS

Among the three groups, donor and recipient characteristics were comparable, except for higher Oto scores and age in group III. Group III showed a longer intensive care unit (ICU) and hospital stay compared with the other two groups. This finding was confirmed when SD history was considered as a continuous variable. However, survival and other mid- and long-term major outcomes were not affected by smoking history. Finally, morphological lesions did not differ between the three groups.

CONCLUSIONS

In our study, SDs were associated with a longer post-operative course, without affecting graft aspects or mid- and long-term outcomes. A definition of pack-years cut-off for organ refusal should be balanced with the other extended criteria donor factors.

Lung cancer: a rare indication for, but frequent complication after lung transplantation

Lung transplantation is an effective and safe therapy for carefully selected patients suffering from a variety of end-stage pulmonary diseases. Lung cancer negatively affects prognosis, particularly in patients who are no longer candidates for complete resection. Lung transplantation can be considered for carefully selected and well staged lung cancer patients with proven, lung-limited, multifocal, (minimally invasive) adenocarcinoma in situ (AIS) (previously called bronchioloalveolar cell carcinoma) causing respiratory failure. Despite a substantial risk of tumour recurrence (33-75%), lung transplantation may offer a survival benefit (50% at 5 years) with best palliation of their disease. Reports on lung transplantation for other low-grade malignancies are rare. Lung transplant candidates at higher risk for developing lung cancer [mainly previous smokers with chronic obstructive lung disease (COPD) and idiopathic pulmonary fibrosis (IPF) or older patients] should be thoroughly and repeatedly screened for lung cancer prior to listing, and preferably also during waiting list time if longer than 1 year, including the use of PET-CT scan and EBUS-assisted bronchoscopy in case of undefined, but suspicious pulmonary abnormalities. Double-lung transplantation should now replace single-lung transplantation in these high-risk patients because of a 6-9% prevalence of lung cancer developing in the remaining native lung. Patients with unexpected, early stage bronchial carcinoma in the explanted lung may have favourable survival without recurrence. Early PET-CT (at 3-6 months) following lung transplantation is advisable to detect early, subclinical disease progression. Donor lungs from (former) smokers should be well examined at retrieval. Suspicious nodules should be biopsied to avoid grafting cancer in the recipient. Close follow-up with regular visits and screening test in all recipients is needed because of the increased risk of developing a primary or secondary cancer in the allograft from either donor or recipient origin.

Lung transplantation in adults and children: putting lung function into perspective

The number of lung transplants performed globally continues to increase year after year. Despite this growing experience, long-term outcomes following lung transplantation continue to fall far short of that described in other solid-organ transplant settings. Chronic lung allograft dysfunction (CLAD) remains common and is the end result of exposure to a multitude of potentially injurious insults that include alloreactivity and infection among others. Central to any description of the clinical performance of the transplanted lung is an assessment of its physiology by pulmonary function testing. Spirometry and the evaluation of forced expiratory volume in 1 s and forced vital capacity, remain core indices that are measured as part of routine clinical follow-up. Spirometry, while reproducible in detecting lung allograft dysfunction, lacks specificity in differentiating the different complications of lung transplantation such as rejection, infection and bronchiolitis obliterans. However, interpretation of spirometry is central to defining the different 'chronic rejection' phenotypes. It is becoming apparent that the maximal lung function achieved following transplantation, as measured by spirometry, is influenced by a number of donor and recipient factors as well as the type of surgery performed (single vs double vs lobar lung transplant). In this review, we discuss the wide range of variables that need to be considered when interpreting lung function testing in lung transplant recipients. Finally, we review a number of novel measurements of pulmonary function that may in the future serve as better biomarkers to detect and diagnose the cause of the failing lung allograft.