Thoracic Summit Part II: Management of Thoracic Disease Past, Present and Future*

Objective. In JCOG0201, we reported the definitions of pathological less invasiveness and elucidated that lung cancer (LC) with a consolidation-to-tumor ratio of ≤0.25 and ≤2 cm in size can be used as a better radiological criterion for a less invasive pathology on preoperative thin-section computed tomography. We have already reported the 5-year safety and efficacy of sublobar resection in the prospective interventional study (JCOG0804/WJOG4507L). The aim of this final analysis was to elucidate the 10-year outcome in JCOG0804/WJOG4507L of sublobar resection for peripheral grand-glass opacity (GGO) dominant LC patients with such radiological features.
Methods. Between May 2009 and April 2011, 333 patients were enrolled from 51 institutions in Japan (median age was 62 at registration) and followed up until May 6, 2021. Of them, sublobar resections were performed in 314 patients (258 wedge resections and 56 segmentectomies), conversion lobectomies were performed in 11 patients, and 8 were ineligible. As an interventional surgical method, wedge resection is performed, and segmentectomy is permitted if the surgical margin is insufficient. The Median follow-up period at the final data cutoff point was 10.1 years.
Results. The 10-year RFS and OS for the 314 patients with sublobar resections were 98.6 % (95% CI, 96.2 – 99·5%) and 98.5% (95% CI, 96.1 – 99.4%), respectively. There was one local recurrence at resection margin. Among the patients, secondary cancers were observed in 43 patients (13.7%: 95% CI, 10.1 -18.0%), of them 19 were secondary LCs (6.1%: 95% CI, 3.7-9.3%).
Conclusions. The long-term results from JCOG0804/WJOG4507L suggested that sublobar resection for peripheral GGO dominant LC patients is a surgical procedure that can fully cured them. The indication of other treatment options would be further investigated. 

Objective
While the practice of procuring DCD organs has increased in recent years, procurement of DCD lungs, in particular, has not progressed as rapidly as other organs. Therefore, further research should investigate improvements to DCD lung recovery protocols to increase the total number recovered and thereby decrease waitlist mortality. However, expansion of DCD lung transplants requires comparing these indicators to DCD abdominal organ donors and applying similar parameters to improve the rate of DCD lung recovery.

Methods
We retrospectively analyzed UNOS data from the Scientific Registry of Transplant Recipients. All donors who donated at ≥1 organ between 10/1999-01/2019 were extracted from the UNOS registry and stratified initially according to DBD and DCD status, and then abdominal organ and lung recovery vs. abdominal organ recovery alone. Associated characteristics of potential DCD abdominal organ and lung donors were compared and a multivariate logistic model with ≥1 transplanted lung and ≥1 transplanted abdominal organ as the outcome was constructed to evaluate the independent effects of important predictors.

Results
Our data consisted of 17,071 DCD potential donors, 16,394 (96.1%) of whom had ≤1 abdominal organ recovered and 657 (3.9%) with both ≤1 abdominal organ and ≤1 lung. Between these cohorts, lung use was associated with blood type, cause of death, smoking history, insulin dependency at the time of transplant, history of diabetes, drug use, mechanism of death, hypertension, age, duration of resuscitation, LVEF, and P/F ratio (P < .001 for all variables). Multivariable regression analysis showed that DCD donors who died from suicide were 2.27 [95% 1.44, 3.57, p<0.001] times more likely, and those who died of intracranial hemorrhage were 9.06 [95% 2.9, 24.21, p<0.001] more likely, to have both an abdominal organ and a lung procured than those who died of natural causes. Lastly, donors with a smoking history were .286 [95% .21, .39, p<0.001] times less likely to have both an abdominal organ and a lung procure than nonsmokers who died of natural causes.

Conclusion
Despite comparable survival outcomes reported for DCD abdominal organs and lungs, this study highlights discrepancies in lung procurement practices that evaluate donor characteristics differently for DCD abdominal organs and lungs. Further study should investigate similar discrepancies in procuring specific abdominal organs. 

Objective: To compare the outcomes of patients receiving lungs transplanted after undergoing ex vivo lung perfusion (EVLP) versus those transplanted conventionally at a single-center with over 14 years of experience.

Methods: Patient data was abstracted from the Toronto Lung Transplant Database between Jan 01, 2008 – Jan 01, 2022. Patients were separated based on whether they received lungs which underwent EVLP or whether they were transplanted conventionally (controls). Patients were matched 1:1 based on medical diagnosis, recipient status, recipient sex, recipient age, BMI, donor age, and calendar year. The primary outcome of the study was the incidence of Primary Graft Dysfunction (PGD) Grade 3 at 72h, with secondary outcomes of post-transplant mechanical ventilation, post-transplant hospital length of stay, intensive care unit (ICU) length of stay, allograft survival analysis and CLAD-Free survival analysis.
Results: There were a total of 533 patients in the EVLP group and 1317 controls. 62.3% of donor lungs placed on EVLP were from Donation after Cardiac Death (DCD) donors vs. 37.3% in the matched control group (P < 0.001). Mean donor P/F ratio was significantly lower for lungs in the EVLP group vs. controls (368 mmHg ± 102 mmHg vs. 426 mmHg ± 86 mmHg, P < 0.001). There were no differences in the incidence of PGD Grade 3 at 72h between the EVLP group and non-EVLP group (12.3% vs. 12.9%, P = 0.23). Furthermore, there were no differences in post-transplant length of mechanical ventilation [2 days (IQR 1 – 4 days) vs. 1.7 days (IQR 1 - 4.1 days), P = 0.1806], post-transplant hospital length of stay [22 days (IQR 16 – 40 days) vs. 25 days (IQR 16 – 42.6 days), P = 0.1730], ICU length of stay [4 days (IQR 2 – 9 days) vs. 4 days (IQR 2 – 11 days), P = 0.3090]. There were no significant differences in allograft survival probability between the two groups (Figure 1, P = 0.82), nor CLAD-Free survival between the groups (P = 0.88).

Conclusions: EVLP has been successfully incorporated in our program for over a decade and is a well-tolerated method to expand the organ donor pool without compromising post-transplant outcomes.