Thoracoscopic precision excision technique for small lung lesions using radiofrequency identification marking

With the introduction of multi-detector computed tomography (CT), the number of incidentally detected small lung nodules has dramatically increased. Determination of lung nodule malignancy is crucial, and an early diagnosis of these indeterminate lesions can lead to subsequent potentially curative treatment. However, there are some limitations to excising these nodules with sublobar resection in a minimally invasive thoracoscopic setting. Under thoracoscopy, although stapler-based wedge resection seems to be the preferred technique, particularly in patients whose lesions are located far from the edge of the lobe, the stapler can unexpectedly sacrifice normal pulmonary parenchyma. To overcome this issue, we have developed a wireless excision precision technique using cone-beam CT-guided electromagnetic navigation bronchoscopy in a minimally invasive thoracoscopic setting. Our technique is implemented in a hybrid operating room, and small tumors can be removed using a radiofrequency identification microchip without intraoperative fluoroscopy and do not require lung palpation under thoracoscopy.

Deep learning-based assay for programmed death ligand 1 immunohistochemistry scoring in non-small cell lung carcinoma: Does it help pathologists score?

Several studies have developed various artificial intelligence (AI) models for immunohistochemical analysis of programmed death ligand 1 (PD-L1) in patients with non-small cell lung carcinoma; however, none have focused on specific ways by which AI-assisted systems could help pathologists determine the tumor proportion score (TPS). Herein, we developed an AI model to calculate the TPS of the PD-L1 22C3 assay and evaluated whether and how this AI-assisted system could help pathologists determine the TPS and analyze how AI-assisted systems could affect pathologists' assessment accuracy. We assessed the four methods of the AI-assisted system: 1) and 2) pathologists first assessed and then referred to automated AI scoring results (1, positive tumor cell percentage; 2, positive tumor cell percentage and visualized overlay image) for a final confirmation, and 3) and 4) pathologists referred to the automated AI scoring results (3, positive tumor cell percentage; 4, positive tumor cell percentage and visualized overlay image) while determining TPS. Mixed model analysis was used to calculate the odds ratios (ORs) with 95% confidence intervals for AI-assisted TPS 1) to 4) compared with pathologists' scoring. For all 584 samples of tissue microarray, the OR for AI-assisted TPS 1) to 4) was 0.94-1.07 and not statistically significant. Of them, we found 332 cases of discordant cases, on which the pathologists' judgments were inconsistent; the ORs for AI-assisted TPS 1), 2), 3), and 4) were 1.28 (1.06-1.54, p = 0.012), 1.29 (1.06-1.55, p = 0.010), 1.28 (1.06-1.54, p = 0.012), and 1.29 (1.06-1.55, p = 0.010), respectively, which were statistically significant. For discordant cases, the OR for each AI-assisted TPS compared with the others was 0.99-1.01 and not statistically significant. This study emphasized the usefulness of the AI-assisted system for cases wherein pathologists had difficulty determining the PD-L1 TPS.

Combination Therapy with EGFR Tyrosine Kinase Inhibitors and TEAD Inhibitor Increases Tumor Suppression Effects in EGFR Mutation-positive Lung Cancer

EGFR-tyrosine kinase inhibitors (TKI) are the first-line therapies for EGFR mutation-positive lung cancer. EGFR-TKIs have favorable therapeutic effects. However, a large proportion of patients with EGFR mutation-positive lung cancer subsequently relapse. Some cancer cells survive the initial treatment with EGFR-TKIs, and this initial survival may be associated with subsequent recurrence. Therefore, we aimed to overcome the initial survival against EGFR-TKIs. We hypothesized that yes-associated protein 1 (YAP1) is involved in the initial survival against EGFR-TKIs, and we confirmed the combined effect of EGFR-TKIs and a YAP1-TEAD pathway inhibitor. The KTOR27 (EGFR kinase domain duplication) lung cancer cell lines established from a patient with EGFR mutation-positive lung cancer and commercially available PC-9 and HCC827 (EGFR exon 19 deletions) lung cancer cell lines were used. These cells were used to evaluate the in vitro and in vivo effects of VT104, a TEAD inhibitor. In addition, YAP1 involvement was investigated in pathologic specimens. YAP1 was activated by short-term EGFR-TKI treatment in EGFR mutation-positive lung cancer cells. In addition, inhibiting YAP1 function using siRNA increased the sensitivity to EGFR-TKIs. Combination therapy with VT104 and EGFR-TKIs showed better tumor-suppressive effects than EGFR-TKIs alone, in vitro and in vivo. Moreover, the combined effect of VT104 and EGFR-TKIs was observed regardless of the localization status of YAP1 before EGFR-TKI exposure. These results suggest that combination therapy with the TEAD inhibitor and EGFR-TKIs may improve the prognosis of patients with EGFR mutation-positive lung cancer.

Non-small cell lung carcinoma with focal coexpression of thyroid transcription factor-1 and Δ Np63/p40: A case report

Most lung carcinomas are subtyped by their morphologies; however, immunohistochemistry is usually performed when it is difficult to determine. The most reliable antibodies for distinguishing lung adenocarcinoma from squamous cell carcinoma are thyroid transcription factor-1 (TTF-1) and p40 (ΔNp63). In general, these markers are mutually exclusive in their expression of lung primary carcinoma; however, a few cases of non-small cell lung carcinoma (NSCLC) with coexpression of both markers have been reported. Examining a tissue microarray of 229 squamous cell carcinomas and 346 adenocarcinomas, we found one case of NSCLC with coexpression of TTF-1 and p40. Herein, we present a 71-year-old man, who had a mass lesion in the left lung apex. A transbronchial lung biopsy was performed, revealing NSCLC. He underwent left upper segmentectomy and lymph node dissection. Macroscopically, the mass showed a white-to-tan solid tumor on the cut surface. Microscopically, the tumor was composed of polygonal tumor cells which had round and vesicular nuclei with prominent nucleoli. They had an abundant amount of cytoplasm, which was slightly eosinophilic or amphophilic. Multinucleated cells with atypical nuclear features were observed to be scattered in some areas. Multifocal necrosis and hemorrhage were also noted. Distinct squamous features and obvious glandular features were absent. Immunohistochemically, the most tumor cells were coexpressed positive for both TTF-1 and p40. In our study, NSCLC with TTF-1 and p40 coexpression is rare; therefore, it is necessary to obtain further data and examine similar cases to establish more precise definitions and clinicopathological features.

Effect of epoprostenol-induced thrombocytopaenia on lung transplantation for pulmonary arterial hypertension

OBJECTIVES

Preoperative intravenous epoprostenol therapy can cause thrombocytopaenia, which may increase the risk of perioperative bleeding during lung transplantation. This study aimed to determine whether lung transplantation can be safely performed in patients with epoprostenol-induced thrombocytopaenia.

METHODS

From June 2008 to July 2022, we performed 37 lung transplants in patients with pulmonary arterial hypertension (PAH), including idiopathic PAH (n = 26), congenital heart disease-associated PAH (n = 7), pulmonary veno-occlusive disease (n = 3) and peripheral pulmonary artery stenosis (n = 1) at our institution. Of these, 26 patients received intravenous epoprostenol therapy (EPO group), whereas 11 patients were treated with no epoprostenol (no-EPO group). We retrospectively analysed the preoperative and postoperative platelet counts and post-transplant outcomes in each group.

RESULTS

Preoperative platelet counts were relatively lower in the EPO group than in the no-EPO group (median EPO: 127 000 vs no-EPO: 176 000/μl). However, blood loss during surgery was similar between the 2 groups (EPO: 2473 ml vs no-EPO: 2615 ml). The platelet counts significantly increased over 1 month after surgery, and both groups showed similar platelet counts (EPO: 298 000 vs no-EPO: 284 000/μl). In-hospital mortality (EPO: 3.9% vs no-EPO: 18.2%) and the 3-year survival rate (EPO: 91.4% vs no-EPO: 80.8%) were similar between the 2 groups.

CONCLUSIONS

Patients with PAH treated with intravenous epoprostenol showed relatively lower platelet counts, which improved after lung transplantation with good post-transplant outcomes.

The impact of vascular division sequence and epithelial-mesenchymal transition status on postoperative recurrence in lung adenocarcinoma

BACKGROUND

The vascular division sequence in video-assisted thoracic surgery (VATS) lung resection is usually determined by the handling difficulty due to the limited surgical view through the scope. However, upfront pulmonary vein division is theoretically desirable to avoid tumor cells spreading by surgical manipulation. Epithelial-mesenchymal transition (EMT) is associated with poor prognosis and an increased number of circulating tumor cells. The purpose of this study is to evaluate the effect of vascular division sequence and EMT on postoperative recurrence.

METHODS

We retrospectively investigated tissue microarrays of 282 lung adenocarcinomas surgically resected between 2001 and 2007. We excluded the cases with segmentectomy, wedge resection, dissemination, insufficient material for staining, or lack of medical records. The effect of vascular division sequence and clinicopathologic factors on recurrence was evaluated in 195 cases.

RESULTS

The upfront pulmonary vein division (V-first) was performed in 60 patients, and the upfront pulmonary artery division (A-first) was performed in 135 patients. The recurrence was observed in 67 patients (13 in V-first and 54 in A-first). Epithelial-mesenchymal transition activation was observed in 104 patients. Multivariable analysis with 195 patients revealed that lymph node metastasis and pleural invasion were risk factors for the recurrence. The stratified multivariable analysis showed that vascular division sequence (A-first) was a risk factor only in the EMT-negative group (91 patients). In the EMT-negative subset, the 5-year relapse-free survival rate was significantly lower in the A-first group than the V-first group (72.6% vs. 92.2%, p  =  0.0136).

CONCLUSIONS

The upfront pulmonary artery division might be a risk factor in patients without EMT activation.

Impact of perioperative airway pathogens on living-donor lobar lung transplantation outcomes

PURPOSE

To elucidate the clinical impact of pathogenic organism (PO) positivity early after transplantation, we evaluated the impact of perioperative airway POs on outcomes after living-donor lobar lung transplantation (LDLLT), where the graft airway is supposed to be sterile from a healthy donor.

METHOD

A retrospective review of 67 adult LDLLT procedures involving 132 living donors was performed. Presence of POs in the recipients' airways was evaluated preoperatively and postoperatively in intensive-care units.

RESULTS

POs were detected preoperatively in 13 (19.4%) recipients. No POs were isolated from the donor airways at transplantation. POs were detected in 39 (58.2%) recipients postoperatively; most were different from the POs isolated preoperatively. Postoperative PO isolation was not associated with short-term outcomes other than prolonged postoperative ventilation. The 5-year overall survival was significantly better in the PO-negative group than in the PO-positive group (89.1% vs. 63.7%, P = 0.014). In the multivariate analysis, advanced age (hazard ratio [HR]: 1.041 per 1-year increase, P = 0.033) and posttransplant PO positivity in the airway (HR: 3.684, P = 0.019) significantly affected the survival.

CONCLUSIONS

The airways of the living-donor grafts were microbiologically sterile. PO positivity in the airway early after transplantation negatively impacted long-term outcomes.

M2-like tumor-associated macrophages promote epithelial-mesenchymal transition through the transforming growth factor β/Smad/zinc finger e-box binding homeobox pathway with increased metastatic potential and tumor cell proliferation in lung squamous cell carcinoma

Epithelial-mesenchymal transition (EMT) promotes primary tumor progression toward a metastatic state. The role of tumor-associated macrophages (TAMs) in inducing EMT in lung squamous cell carcinoma (LUSC) remains unclear. We aimed to clarify the significance of TAMs in relation to EMT in LUSC. We collected 221 LUSC specimens from patients who had undergone surgery. Immunohistochemistry was performed to evaluate M1-like and M2-like TAM distribution and EMT by E-cadherin and vimentin staining. Human LUSC cell lines (H226 and EBC-1) and a human monocyte cell line (THP-1) were used for in vitro experiments. M2-like polarization of TAMs and EMT marker expression in LUSC cells were evaluated by western blotting. The biological behavior of LUSC cells was evaluated by migration, invasion, and cell proliferation assays. Immunohistochemical analysis showed that 166 (75.1%) tumors were E-cadherin-positive and 44 (19.9%) were vimentin-positive. M2-like TAM density in the tumor stroma was significantly associated with vimentin positivity and worse overall survival. Western blotting demonstrated higher levels of CD163, CD206, vascular endothelial growth factor, and transforming growth factor beta 1 (TGF-β1) in TAMs versus unstimulated macrophages. Furthermore, increased TGF-β1 secretion from TAMs was confirmed by ELISA. TAM-co-cultured H226 and EBC-1 cells exhibited EMT (decreased E-cadherin, increased vimentin). Regarding EMT-activating transcriptional factors, phosphorylated Smad3 and ZEB-family proteins were higher in TAM-co-cultured LUSC cells than in parental cells. TAM-co-cultured H226 and EBC-1 cells demonstrated enhanced migration and invasion capabilities and improved proliferation. Overall, the present study suggests that TAMs can induce EMT with increased metastatic potential and tumor cell proliferation in LUSC.

Deep Learning for Predicting Effect of Neoadjuvant Therapies in Non-Small Cell Lung Carcinomas With Histologic Images

Neoadjuvant therapies are used for locally advanced non-small cell lung carcinomas, whereby pathologists histologically evaluate the effect using resected specimens. Major pathological response (MPR) has recently been used for treatment evaluation and as an economical survival surrogate; however, interobserver variability and poor reproducibility are often noted. The aim of this study was to develop a deep learning (DL) model to predict MPR from hematoxylin and eosin-stained tissue images and to validate its utility for clinical use. We collected data on 125 primary non-small cell lung carcinoma cases that were resected after neoadjuvant therapy. The cases were randomly divided into 55 for training/validation and 70 for testing. A total of 261 hematoxylin and eosin-stained slides were obtained from the maximum tumor beds, and whole slide images were prepared. We used a multiscale patch model that can adaptively weight multiple convolutional neural networks trained with different field-of-view images. We performed 3-fold cross-validation to evaluate the model. During testing, we compared the percentages of viable tumor evaluated by annotator pathologists (reviewed data), those evaluated by nonannotator pathologists (primary data), and those predicted by the DL-based model using 2-class confusion matrices and receiver operating characteristic curves and performed a survival analysis between MPR-achieved and non-MPR cases. In cross-validation, accuracy and mean F1 score were 0.859 and 0.805, respectively. During testing, accuracy and mean F1 score with reviewed data and those with primary data were 0.986, 0.985, 0.943, and 0.943, respectively. The areas under the receiver operating characteristic curve with reviewed and primary data were 0.999 and 0.978, respectively. The disease-free survival of MPR-achieved cases with reviewed and primary data was significantly better than that of the non-MPR cases (P<.001 and P=.001), and that predicted by the DL-based model was almost identical (P=.005). The DL model may support pathologist evaluations and can offer accurate determinations of MPR in patients.

Outcomes of immune checkpoint inhibitors for postoperative recurrence of non-small cell lung cancer

OBJECTIVES

Immune checkpoint inhibitors (ICIs) are effective treatment options for patients with advanced non-small cell lung cancer (NSCLC); however, there is a dearth of data on outcomes of patients receiving ICIs for postoperative recurrence. The objective of this study was to investigate the short- and long-term outcomes of patients who received ICIs for postoperative recurrence.

METHODS

A retrospective chart review was performed to identify consecutive patients who received ICIs for postoperative recurrence of NSCLC. We investigated therapeutic responses, adverse events, progression-free survival (PFS), and overall survival (OS). Survival outcomes were estimated using the Kaplan-Meier method. Univariable and multivariable analyses were performed using the Cox proportional hazards model.

RESULTS

Eighty-seven patients, with a median age of 72 years were identified between 2015 and 2022. The median follow-up period after ICI initiation was 13.1 months. Adverse events of grade ≥ 3 were observed in 29 (33.3%) patients, including 17 (19.5%) patients with immune-related adverse events. The median PFS and OS of the whole cohort were 3.2 and 17.5 months, respectively. Limited to those receiving ICIs as first-line therapy, the median PFS and OS were 6.3 and 25.0 months, respectively. On multivariable analysis, smoking history (HR: 0.29, 95% CI 0.10-0.83) and non-squamous cell histology (HR: 0.25, 95% CI 0.11-0.57) were associated with more favorable PFS in patients receiving ICIs as first-line treatment.

CONCLUSIONS

Outcomes in patients receiving ICIs as first-line treatment appear acceptable. A multi-institutional study is required to confirm our findings.

Protocol for cell-type-specific tissue reconstruction in the murine lung fibrogenic microenvironment

Pulmonary fibrosis is a process characterized by epithelial injury and fibroblast activation. It is also well recognized as a predisposition to lung cancer. Here, we present a protocol to establish an in vivo model to evaluate the dynamics of alveolar epithelial type 2 cells and lung cancer cells in the context of the lung fibrogenic microenvironment. Utilizing the cell transfer technique, we detail a basis for therapeutic approaches in pulmonary fibrosis and tools for precision medicine against lung cancer. For complete details on the use and execution of this protocol, please refer to Miyata et al. (2022).1.

Clinicopathological features of cytokeratin 5-positive pulmonary adenocarcinoma

Cytokeratin 5 (CK5) is a marker for pulmonary squamous cell carcinoma; however, CK5 is sometimes present in pulmonary adenocarcinoma (ADC), and there is insufficient information regarding the clinicopathological features of CK5-positive ADC. We aimed to explore the clinicopathological characteristics of CK5-positive ADC using immunohistochemistry. We prepared the following two cohorts: a resected cohort containing 220 resected tumours for primarily studying the detailed morphological characteristics, and a tissue microarray (TMA) cohort containing 337 samples for investigating the associations of CK5 expression with other protein expressions, genetic and prognostic findings. CK5-positive ADC was defined to have ≥ 10% tumour cells and presence of CK5-positive tumour cells in the resected and TMA cohorts, respectively. CK5-positive ADCs were identified in 91 (16.3%) patients in the combined cohort. CK5-positive ADCs had male predominance (P = 0.012), smoking history (P = 0.001), higher stage (P < 0.001), histological high-grade components (P < 0.001), vascular invasion (P < 0.001), mucinous differentiation (P < 0.001), spread through airspaces (P < 0.001), EGFR wild-type (P < 0.001), KRAS mutations (P < 0.001), ALK rearrangement (P < 0.001) and ROS1 rearrangement (P = 0.002). In the resected cohort, more than half the CK5-positive ADCs (19 cases, 65.5%) showed mucinous differentiation; the remaining cases harboured high-grade components. In the TMA cohort, CK5-positive ADCs correlated with TTF-1 negativity (P = 0.002) and MUC5B, MUC5AC and HNF4alpha positivity (P < 0.001, 0.048, < 0.001). Further, CK5-positive ADCs had significantly lower disease-free and overall survival rates than CK5-negative ADCs (P < 0.001 for each). Additionally, multivariate analysis revealed that CK5 expression was an independent poor prognostic factor. CK5-positive ADCs showed aggressive clinical behaviour, with high-grade morphology and mucinous differentiation.

ZBTB2 links p53 deficiency to HIF-1-mediated hypoxia signaling to promote cancer aggressiveness

Aberrant activation of the hypoxia-inducible transcription factor HIF-1 and dysfunction of the tumor suppressor p53 have been reported to induce malignant phenotypes and therapy resistance of cancers. However, their mechanistic and functional relationship remains largely unknown. Here, we reveal a mechanism by which p53 deficiency triggers the activation of HIF-1-dependent hypoxia signaling and identify zinc finger and BTB domain-containing protein 2 (ZBTB2) as an important mediator. ZBTB2 forms homodimers via its N-terminus region and increases the transactivation activity of HIF-1 only when functional p53 is absent. The ZBTB2 homodimer facilitates invasion, distant metastasis, and growth of p53-deficient, but not p53-proficient, cancers. The intratumoral expression levels of ZBTB2 are associated with poor prognosis in lung cancer patients. ZBTB2 N-terminus-mimetic polypeptides competitively inhibit ZBTB2 homodimerization and significantly suppress the ZBTB2-HIF-1 axis, leading to antitumor effects. Our data reveal an important link between aberrant activation of hypoxia signaling and loss of a tumor suppressor and provide a rationale for targeting a key mediator, ZBTB2, to suppress cancer aggressiveness.

Postoperative tegafur-uracil for stage I lung adenocarcinoma: first real-world data with an exploratory subgroup analysis

PURPOSE

The effect of postoperative tegafur-uracil on overall survival (OS) after resection of stage I adenocarcinoma has been shown in clinical trials. The purpose of this study was to investigate whether findings from randomized trials of adjuvant tegafur-uracil are reproducible in a real-world setting.

METHODS

A retrospective cohort study was performed using a multi-institutional database that included all patients who underwent complete resection of pathological stage I adenocarcinoma between 2014 and 2016. Survival outcomes for patients managed with and without tegafur-uracil were analyzed using the Kaplan-Meier method and a Cox proportional hazards model for the whole patient cohort and in a selected cohort based on eligibility criteria of a previous randomized trial. Propensity score matching was used to adjust for confounding effects.

RESULTS

After propensity score matching, the hazard ratios for OS were 0.57 (95% confidence interval (CI) 0.29-1.14, P = 0.11) in the whole cohort and 0.69 (95% CI 0.32-1.50, P = 0.35) in the selected cohort.

CONCLUSIONS

The effects of tegafur-uracil in this retrospective study appear to be consistent with those found in randomized clinical trials. These effects may be maximized in patients aged from 45 to 75 years.

A novel cell-based assay for the high-throughput screening of epithelial-mesenchymal transition inhibitors: Identification of approved and investigational drugs that inhibit epithelial-mesenchymal transition

OBJECTIVES

Lung cancer with distant metastases is associated with a very poor prognosis, and epithelial-mesenchymal transition (EMT) contributes to cancer metastasis. Therefore, elucidation and inhibition of EMT signaling in lung cancer may be a new therapeutic strategy for improving the prognosis of patients. We constructed a high-throughput screening system for EMT inhibitors. Using this system, we aimed to identify compounds that indeed inhibit EMT.

MATERIALS AND METHODS

We generated a luciferase reporter cell line using A549 human lung cancer cells and E-cadherin or vimentin as EMT markers. EMT was induced by transforming growth factor β1 (TGF-β1), and candidate EMT inhibitors were screened from a library of 2,350 compounds. The selected compounds were further tested using secondary assays to verify the inhibition of EMT and invasive capacity of cells.

RESULTS

Values obtained by the assay were adjusted for the number of viable cells and scored by determining the difference between mean values of the positive and negative control groups. Four compounds were identified as novel candidate drugs. Among those, one (avagacestat) and two compounds (GDC-0879 and levothyroxine) improved the expression of E-cadherin and vimentin, respectively, in epithelial cells. GDC-0879 and levothyroxine also significantly inhibited the invasive capacity of cells.

CONCLUSION

We systematically screened approved, investigational, and druggable compounds with inhibitory effects using a reporter assay, and identified candidate drugs for EMT inhibition.

Electromagnetic navigation bronchoscopy-guided radiofrequency identification marking in wedge resection for fluoroscopically invisible small lung lesions

OBJECTIVES

We developed a novel wireless localization technique after electromagnetic navigation bronchoscopy-guided radiofrequency identification marker placement for fluoroscopically invisible small lung lesions. We conducted an observational study to investigate the feasibility of this technique and retrospectively compared 2 marking approaches with or without cone-beam computed tomography (CBCT).

METHODS

Consecutive patients from January 2021 to March 2022 in our institution were enrolled. Markers were placed central to the lesions either in a bronchoscopic suite under intravenous anaesthesia or a hybrid operation theatre with CBCT under general anaesthesia. The efficacy of the 2 marking methods was compared using an inverse probability of treatment weighting adjusted analysis.

RESULTS

Totally 80 markers were placed (45 under CBCT and 35 under fluoroscopy) for 74 patients with 80 lesions [mean size: 6.9 mm (interquartile range: 5.1-8.4) at a median depth from the pleura of 14.0 mm (interquartile range: 8.5-19.5)]. The median distance from marker to lesion was 9.1 mm, with a pleural depth of 15.5 mm. The tumour resection rate was 97.5% (78/80) with the median surgical margin of 10.0 mm (interquartile range: 8.0-11.0). Although the bronchoscopy time was longer using CBCT because of the need for 2.8 scans per lesion, the distance from the marker to the lesion was shorter for marking using CBCT than marking using fluoroscopy (adjusted difference: -4.56, 95% confidence interval: -6.51 to -2.61, P < 0.001).

CONCLUSIONS

Electromagnetic navigation bronchoscopy-guided radiofrequency identification marking provided a high tumour resection rate with sufficient surgical margins.

Prognostic impact of pathologically confirmed rib invasion in patients with lung cancer requiring chest wall resection

BACKGROUND

Primary lung cancer that invades the chest wall is classified as T3 regardless of the depth of invasion. This study assessed the prognostic impact of pathologically confirmed rib invasion in patients with pT3N0-1 lung cancer requiring chest wall resection.

METHODS

We retrospectively analyzed the records of patients with non-small cell lung cancer (NSCLC) who underwent combined lung and chest wall resection with rib involvement from 2006 to 2019. The median follow-up period was 64.0 months.

RESULTS

In total, 42 patients (41 men, 1 woman) were enrolled. The median patient age was 64 years (range, 42-79 years). The median tumor size before treatment was 56.5 mm (range, 21-80 mm), and an osteolytic sign was identified on computed tomography (CT) in 42.9% (18/42). Among 27 patients who received induction chemoradiotherapy, 5 (18.5%) achieved a complete pathological response. The operations comprised 36 lobectomies, 5 segmentectomies, and 1 wedge resection with resection of 2.5 ribs on average. Pathological examination revealed rib invasion in 18 (42.9%) patients. The 5-year disease-free and overall survival rates with pathological rib invasion were 44.4% and 77.4% (P=0.0114), respectively and those without pathological rib invasion were 44.7% and 81.3% (P=0.0222), respectively. Pathologically confirmed rib invasion was the only factor identified to have a prognostic impact in the univariate and multivariate analyses [hazard ratio (HR), 5.98; 95% confidence interval (CI): 1.37-26.1]. Locoregional recurrence and distant metastases were more common in patients with than without pathologically confirmed rib invasion [4 (22.2%) and 6 (33.3%), respectively, among 18 patients with pathological rib invasion; 2 (8.3%) and 3 (12.5%), respectively, among 24 patients without pathological rib invasion] (P=0.0073).

CONCLUSIONS

Pathologically confirmed rib invasion was found to have a significant unfavorable prognostic impact in patients with pT3N0-1 lung cancer requiring chest wall resection. Multimodal therapy may be preferable in these patients to prevent local and distant relapse.

Nrf2/p‑Fyn/ABCB1 axis accompanied by p‑Fyn nuclear accumulation plays pivotal roles in vinorelbine resistance in non‑small cell lung cancer

Adjuvant cisplatin‑vinorelbine is a standard therapy for stage II/III lung cancer. However, a poor survival rate of patients with lung cancer is attributed to vinorelbine resistance arising from ATP‑binding cassette (ABC) sub‑family B member 1 (ABCB1) and phosphorylated Fyn (p‑Fyn) overexpression. However, the underlying mechanisms remain unclear. NF‑E2‑related factor 2 (Nrf2) regulates the ABC family and activates the nuclear transport of Fyn. The present study evaluated the roles of the Nrf2/p‑Fyn/ABCB1 axis in vinorelbine‑resistant (VR) cells and clinical samples. To establish VR cells, H1299 cells were exposed to vinorelbine, and the intracellular reactive oxygen species (ROS) level in the H1299 cells was determined using a DCFH‑DA assay. The total and subcellular expression of Nrf2, ABCB1 and p‑Fyn in VR cells was evaluated. Immunofluorescence was used to detect the subcellular localization of p‑Fyn in VR cells. A cell viability assay was used to examine whether the sensitivity of VR cells to vinorelbine is dependent on Nrf2 activity. Immunohistochemistry was performed on 104 tissue samples from patients with lung cancer who underwent surgery followed by cisplatin‑vinorelbine treatment. The results revealed that persistent exposure to vinorelbine induced intracellular ROS formation in H1299 cells. p‑Fyn was localized in the nucleus, and ABCB1 and Nrf2 were overexpressed in VR cells. ABCB1 expression was dependent on Nrf2 downstream activation. The decreased expression of Nrf2 restored the sensitivity of VR cells to vinorelbine. In the surgical samples, Nrf2 and ABCB1 were associated with disease‑free survival, and p‑Fyn was associated with overall survival (P<0.05). On the whole, the present study demonstrates that Nrf2 upregulates ABCB1 and, accompanied by the nuclear accumulation of p‑Fyn, induces vinorelbine resistance. These findings may facilitate the development of drug resistance prevention strategies or new drug targets against non‑small cell lung cancer.

Propensity score-based analysis of stereotactic body radiotherapy, lobectomy and sublobar resection for stage I non-small cell lung cancer

We applied two propensity score-based analyses to simultaneously compare three treatment modalities-stereotactic body radiotherapy (SBRT), lobectomy, or sublobar resection (SLR)-for stage I non-small cell lung cancer (NSCLC), with the aim of clarifying the average treatment effect (ATE) and formulating a risk-adapted approach to treatment selection. A retrospective review of 823 patients aged ≥65 years who underwent SBRT, lobectomy, or SLR for stage I NSCLC was conducted. The following two analyses using machine learning-based propensity scores were performed: (i) propensity score weighting (PSW) to assess the ATE in the entire cohort, and (ii) propensity score subclassification (PSS) to evaluate treatment effects of subgroups. PSW showed no significant difference in the 5-year overall survival (OS) between SBRT and SLR (60.0% vs 61.2%; P = 0.70) and significant difference between SBRT and lobectomy (60.0% vs 77.6%; P = 0.026). Local (LR) and distant recurrence (DR) rates were significantly lower in lobectomy than in SBRT, whereas there was no significant difference between SBRT and SLR. PSS identified four subgroups with different patient characteristics: lobectomy-oriented (5-year cumulative incidences of non-lung cancer death, 7.5%), SLR-oriented (14.2%), SBRT-oriented (23.8%) and treatment-neutral subgroups (16.1%). Each subgroup showed different survival trends regarding the three treatments. The ATE of SBRT was not significantly different from that of SLR, but it was inferior to lobectomy. Four subgroups with different risks of non-lung cancer death and different survival trends for each treatment were identified. These would help decision-making for patients with stage I NSCLC.

Lung fibrogenic microenvironment in mouse reconstitutes human alveolar structure and lung tumor

A mesenchymal cell activation is a hallmark event of pulmonary fibrosis. Alveolar type 2 (AT2) cells are progenitor cells that maintain alveolar homeostasis, and their damage is assumed to be an initiating event for pulmonary fibrosis. However, the interaction between the lung fibrogenic microenvironment and AT2 cell dynamics remains to be elucidated. Here, we report a unique role of the lung fibrogenic microenvironment, where cell type-specific tissue reconstruction is achieved by exogenous cell transplantation. We found that in the lung fibrogenic microenvironment the AT2 cell pool was depleted, whereas mesenchymal cells could promote intact AT2 cell proliferation in vitro. Furthermore, exogenously transplanted AT2 cells formed alveolar colonies and ameliorated pulmonary fibrosis. Exogenous tumor cells formed tumor nests with relevant histological and transcriptional properties. Human primary cells were adaptable to this microenvironment, facilitating epithelial cell-targeted therapy in pulmonary fibrosis and the establishment of patient-derived xenografts for precision medicine in lung cancer.

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Severe bleomycin-induced lung injury causes a significant AT2 cell loss

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Mesenchymal cells in the fibrogenic lung supports AT2 cell proliferation

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AT2 cell transplantation ameliorates bleomycin-induced pulmonary fibrosis

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Novel orthotopic lung cancer models are established for patient-derived xenografts

Epidermal growth factor receptor tyrosine kinase inhibitors as first-line treatment for postoperative recurrent EGFR-mutated lung adenocarcinoma: a multi-institutional retrospective study

OBJECTIVES

To analyze the long-term survival outcomes and prognostic factors of patients receiving epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) as first-line treatment for postoperative recurrent EGFR-mutated lung adenocarcinoma.

METHODS

Using a multi-institutional database, we performed a retrospective chart review to identify all patients who had undergone complete resection of stage I-III EGFR-mutated lung adenocarcinoma at 11 acute care hospitals between 2009 and 2016, and had received first-line EGFR-TKI treatment for postoperative recurrence. Adverse events, progression-free survival (PFS), and overall survival (OS) were investigated. Survival outcomes were assessed using Kaplan-Meier analysis. Cox proportional hazards models were used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for PFS and OS.

RESULTS

The study sample comprised 154 patients with a median age of 69. The total numbers of events were 101 for PFS and 60 for OS. The median PFS and OS were 26.1 months and 55.4 months, respectively. In the multivariable analysis, EGFR ex 21 L858R mutation (HR: 1.71, 95% CI: 1.15-2.55) and shorter disease-free intervals (HR: 0.98, 95% CI: 0.96-0.99) were significantly associated with shorter PFS. Age (HR: 1.03, 95% CI: 1.00-1.07), smoking history (HR: 2.31, 95% CI: 1.35-3.94) and pathological N2 disease at the initial surgery (HR: 2.30, 95% CI: 1.32-4.00) were significantly associated with shorter OS.

CONCLUSIONS

First-line EGFR-TKI treatment was generally associated with favorable survival outcomes in patients with postoperative recurrent EGFR-mutated lung adenocarcinoma. EGFR ex 21 L858R mutation may be an important prognostic factor for shorter PFS.

Strategy for lung parenchyma-sparing bronchial resection: a case series report

Lung parenchyma-sparing bronchial resection is uncommon, and the operative procedure depends on the cause and location of the stenosis. We present 6 cases and discuss the different surgical strategies for sleeve resection of the central airway without lung resection. Bronchoplasty for the main bronchus and truncus intermedius was performed with a posterolateral approach. We resected the right main bronchus including the right lateral wall of the lower trachea and half of the carina obliquely and performed an anastomosis. The tumour in the left lobar bronchus was exposed and removed by transient division of the accompanying pulmonary artery. Although post-transplant stenosis and malacia can pose a challenge, bronchoplasty can be used as a definitive treatment in experienced centres.

Peritumoral radiomics features on preoperative thin-slice CT images can predict the spread through air spaces of lung adenocarcinoma

The spread through air spaces (STAS) is recognized as a negative prognostic factor in patients with early-stage lung adenocarcinoma. The present study aimed to develop a machine learning model for the prediction of STAS using peritumoral radiomics features extracted from preoperative CT imaging. A total of 339 patients who underwent lobectomy or limited resection for lung adenocarcinoma were included. The patients were randomly divided (3:2) into training and test cohorts. Two prediction models were created using the training cohort: a conventional model based on the tumor consolidation/tumor (C/T) ratio and a machine learning model based on peritumoral radiomics features. The areas under the curve for the two models in the testing cohort were 0.70 and 0.76, respectively (P = 0.045). The cumulative incidence of recurrence (CIR) was significantly higher in the STAS high-risk group when using the radiomics model than that in the low-risk group (44% vs. 4% at 5 years; P = 0.002) in patients who underwent limited resection in the testing cohort. In contrast, the 5-year CIR was not significantly different among patients who underwent lobectomy (17% vs. 11%; P = 0.469). In conclusion, the machine learning model for STAS prediction based on peritumoral radiomics features performed better than the C/T ratio model.

Abstract 6075: ROS-Nrf2-ABCB1 axis accompanied with pFyn nuclear accumulation plays pivotal roles in vinorelbine resistance in non-small cell lung cancer

Introduction: Adjuvant cisplatin-vinorelbine is standard therapy for stage II/III lung cancer. Poor survival in lung cancer can be attributed to vinorelbine resistance arising from ABC sub-family B member 1 (ABCB1) and phosphorylated Fyn (pFyn) overexpression. However, the underlying mechanism remains unclear. Nrf2 regulates the cell-protective ABC family and activates nuclear transport of Fyn. Here, we aimed to evaluate the ROS-Nrf2-ABCB1 axis in both vinorelbine-resistant (VR) cells and clinical samples.

Methods: We established VR cells by exposing H1299 cells to vinorelbine, and determined intracellular reactive oxygen species (ROS) level of H1299 cells induced by vinorelbine using DCFH-DA. We evaluated the total and subcellular expression of Nrf2, ABCB1, and pFyn in VR cells and performed immunofluorescence of VR cells to confirm the precise subcellular localization of pFyn. Cell viability assay was used to examine whether the sensitivity of VR cells to vinorelbine depends on Nrf2 activity. For immunohistochemistry, we used 104 tissue samples from lung cancer patients who underwent surgery followed by cisplatin-vinorelbine treatment between December 2006 and June 2018.

Results: Persistent exposure to vinorelbine induced intracellular ROS formation of H1299 cells. Both ABCB1 and Nrf2 were overexpressed in VR cells, and ABCB1 expression was dependent on Nrf2 downstream activation. Subcellular fractionation and immunofluorescence revealed nuclear accumulation of pFyn in VR cells. Decreased expression of Nrf2 restored the sensitivity of VR cells to vinorelbine. In the 104 surgical samples, Nrf2 and ABCB1 were significantly associated with disease-free survival (p = 0.029 and 0.035, respectively), and pFyn was associated with overall survival (p = 0.040).

Conclusions: ROS-Nrf2 upregulates ABCB1 and accompanied by nuclear accumulation of pFyn, induces vinorelbine resistance. Our findings may facilitate drug resistance prevention strategies or new drug target development against non-small cell lung cancer.

Citation Format: Shigeyuki Tamari, Toshi Menju, Toshiya Toyazaki, Hideaki Miyamoto, Naohisa Chiba, Misa Noguchi, Hiroshi Date. ROS-Nrf2-ABCB1 axis accompanied with pFyn nuclear accumulation plays pivotal roles in vinorelbine resistance in non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6075.

Fissure-last technique for left upper lobe lung cancer with interlobar invasion: how to do it?

The fissure-last technique is used to minimize postoperative air leak after anatomical lung resection when the interlobar pulmonary artery is inaccessible through the fused fissure. After first dividing the hilar bronchovascular structures, the incomplete fissure is divided using staplers. This technique can be applied for lobectomy combined with segmentectomy in lung cancer with interlobar invasion. We performed this thoracoscopic fissure-last technique in a lung cancer patient in the left upper lobe with invasion to the superior segment (S6) in the left lower lobe.

Specialized Proresolving Lipid Meditators Agonistic to Formyl Peptide Receptor Type 2 Attenuate Ischemia-reperfusion Injury in Rat Lung

BACKGROUND

Lung ischemia-reperfusion injury (IRI) is a form of acute lung injury characterized by nonspecific alveolar damage and lung edema due to robust inflammation. Little is known about the roles of specialized proresolving lipid mediators (SPMs) in lung IRI. Therefore, we aimed to evaluate the dynamic changes in endogenous SPMs during the initiation and resolution of lung IRI and to determine the effects of SPM supplementation on lung IRI.

METHODS

We used a rat left hilar clamp model with 90 min of ischemia, followed by reperfusion. Dynamic changes in endogenous SPMs were evaluated using liquid chromatography-tandem mass spectrometry.

RESULTS

Endogenous SPMs in the left lung showed a decreasing trend after 1 h of reperfusion. Oxygenation improved between 3 and 7 d following reperfusion; however, the level of endogenous SPMs remained low compared with that in the naïve lung. Among SPM receptors, only formyl peptide receptor type 2 (ALX/FPR2) gene expression in the left lung was increased 3 h after reperfusion, and the inflammatory cells were immunohistochemically positive for ALX/FPR2. Administration of aspirin-triggered (AT) resolvin D1 (AT-RvD1) and AT lipoxin A4 (AT-LXA4), which are agonistic to ALX/FPR2, immediately after reperfusion improved lung function, reduced inflammatory cytokine levels, attenuated lung edema, and decreased neutrophil infiltration 3 h after reperfusion. The effects of AT-RvD1 and AT-LXA4 were not observed after pretreatment with the ALX/FPR2 antagonist.

CONCLUSIONS

The level of intrapulmonary endogenous SPMs decreased during lung IRI process and the administration of AT-RvD1 and AT-LXA4 prevented the exacerbation of lung injury via ALX/FPR2.

Proteolysis of a histone acetyl reader, ATAD2, induces chemoresistance of cancer cells under severe hypoxia by inhibiting cell cycle progression in S phase

Cancer cells acquire chemoresistance in hypoxic regions of solid tumors, which is suggested to be at least partly due to reduction of their proliferative activity. However, molecular mechanisms behind it have not been fully elucidated. Here, we revealed the importance of active proteolysis of a histone acetylation reader, ATPase family AAA domain containing 2 (ATAD2), under hypoxia. We found that inactivation of an O₂/Fe²⁺/α-ketoglutarate-dependent dioxygenase triggered ATAD2 proteolysis by the proteasome system upon severe hypoxia in a hypoxia-inducible factors (HIFs)-independent manner. Consistently, ATAD2 expression levels were markedly lower in perinecrotic hypoxic regions in both xenografted and clinical tumor tissues. The ATAD2 proteolysis was accompanied by a decrease in the amount of acetylated histone H3 lysine 27 and inhibited cell cycle progression from the early to late S phase under severe hypoxia. The retardation of S phase progression induced chemoresistance, which was blocked by overexpression of ATAD2. Together, these results indicate that ATAD2 proteolysis upon severe hypoxia induces chemoresistance of cancer cells through heterochromatinization and the subsequent retardation of S phase progression; therefore, inhibition of ATAD2 proteolysis is expected to be a strategy to overcome chemoresistance of hypoxic tumor cells.

High programmed death ligand 1 expression in carcinomatous components predicts a poor prognosis in pulmonary pleomorphic carcinoma

PURPOSE

This study reviewed the clinicopathological characteristics and programmed death ligand 1 (PD-L1) expression of 46 patients with pulmonary pleomorphic carcinoma to better understand its clinical behavior and factors affecting the survival.

METHODS

Data of patients with pulmonary pleomorphic carcinomas resected in our institution were retrospectively reviewed. The tumors were classified as carcinomatous or sarcomatous according to the tissue components. Pathological characteristics were evaluated on hematoxylin and eosin-stained sections. The percentages of tumor cells with membrane staining for PD-L1 in carcinomatous and sarcomatous components were determined.

RESULTS

We reviewed data of 46 patients (41 males, 5 females; median age 70.5 years old, range 36-83 years old). Most patients with pulmonary pleomorphic carcinoma expressed PD-L1 (80.4%), and the proportion of PD-L1 expression in tumor cells was significantly higher in sarcomatous components than in carcinomatous components. In univariable analyses, high p-stage (III), necrosis on pathological findings, and high PD-L1 expression in carcinomatous components (≥ 50%) were poor prognostic factors for the overall survival. In multivariable analyses, high PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery.

CONCLUSIONS

High PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery.

Electromagnetic navigation bronchoscopy versus virtual bronchoscopy navigation for improving the diagnosis of peripheral lung lesions: analysis of the predictors of successful diagnosis

PURPOSE

To investigate if electromagnetic navigation bronchoscopy (ENB) improves the diagnostic yield for peripheral lung lesions from that achieved by virtual bronchoscopy navigation (VBN).

METHODS

This retrospective study compared the results of 100 ENB-transbronchial lung biopsies (TBLBs) with those of 50 VBN-TBLBs at a single institution.

RESULTS

ENB improved the diagnostic yield significantly compared with VBN (64.0% for 19.4 ± 9.0 mm tumors vs. 46.0% for 27.6 ± 8.9 mm tumors; p < 0.0001). Irrespective of the bronchus sign, ENB was more favorable than VBN, with 81.0% (47/58) achieved by ENB vs. 60.0% (21/35) achieved by VBN in the presence of the positive bronchus sign (p = 0.0283), and 40.5% (17/42) achieved by ENB vs. 13.3% (2/15) achieved by VBN in the absence of the bronchus sign (p = 0.0431). Univariate analysis identified tumor size (p = 0.0048), amount of intravenous sedation (p = 0.0182), registration time (p = 0.0111), minimum distance to target (p = 0.0244), and the bronchus sign (p < 0.0001) as factors that affected the yield significantly for ENB. Multivariate analysis identified the bronchus sign (odds ratio 6.74; 95% CI 1.84-24.7) and the registration time (OR 1.01; 95% CI 1.00-1.02) as significant factors.

CONCLUSIONS

Despite the bronchus sign being a significant factor, ENB improved the diagnostic yield of smaller lesions significantly, compared with VBN, regardless of the bronchus sign.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors as a first-line treatment for postoperative recurrent and EGFR-mutated non-small-cell lung cancer

 

OBJECTIVES

To clarify survival outcomes and prognostic factors of patients receiving epidermal growth factor receptor (EGFR) - tyrosine kinase inhibitors (TKIs) as first-line treatment for postoperative recurrence.

METHODS

A retrospective chart review was performed to identify consecutive patients who received EGFR-TKIs as first-line treatment for postoperative recurrence of non-small-cell lung cancer (NSCLC) harbouring EGFR gene mutations at our institution between August 2002 and October 2020. Therapeutic response, adverse events, progression-free survival (PFS) and overall survival (OS) were investigated. Survival outcomes were assessed using the Kaplan–Meier analysis. The Cox proportional hazards model was used for univariable and multivariable analyses.

RESULTS

Sixty-four patients were included in the study. The objective response and disease control rates were 53% and 92%, respectively. Grade 3 or greater adverse events were noted in 4 (6.3%) patients, including 1 patient (1.6%) of interstitial pneumonia. The median follow-up period was 28.5 months (range 3–202 months). The total number of events was 43 for PFS and 23 for OS, respectively. The median PFS was 18 months, and the median OS was 61 months after EGFR-TKI treatment. In multivariable analysis, osimertinib showed a tendency to prolong PFS [hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.12–1.1; P = 0.071], whereas the micropapillary component was significantly associated with shorter OS (HR 2.1, 95% CI 1.02–6.9; P = 0.045).

CONCLUSIONS

EGFR-TKIs as first-line treatment appeared to be a reasonable treatment option in selected patients with postoperative recurrent EGFR-mutated NSCLC. Osimertinib and the micropapillary component may be prognostic factors.

Prognostic factors related to postoperative survival in the newly classified clinical T4 lung cancer

OBJECTIVES

T4 lung cancer has become a more heterogeneous group since the 8th edition of tumour, node, metastasis classification. The aim of this study was to identify predictive factors related to post-surgical survival in patients with clinical T4 non-small-cell lung cancer (NSCLC), based on the 8th edition of the classification.

METHODS

We retrospectively reviewed consecutive patients with clinical T4 NSCLC who underwent resection between January 2006 and December 2016, to identify factors associated with overall survival.

RESULTS

Ninety-three patients were identified. The criteria for clinical T4 disease included tumours larger than 7 cm (n = 54), great vessels or left atrial invasion (n = 22), mediastinal invasion (n = 11), vertebral invasion (n = 3), tracheal or carina invasion (n = 3), diaphragm invasion (n = 1) and ipsilateral different lobe pulmonary metastasis (n = 2). The postoperative nodal status was 0, 1, 2 and 3 in 59, 18, 15 and 1 patient, respectively. R0 resection was achieved in 80 patients, and the 30-day mortality was 0%. The median follow-up time was 37.6 months, and the 5-year overall survival rate was 56.3%. The multivariable analysis revealed that nodal status and R-status were significant prognostic factors for postoperative survival [hazard ratio (HR) 2.62, 95% confidence interval (CI) 1.20-5.72, P = 0.016 and HR 3.29, 95% CI 1.45-7.44, P = 0.004].

CONCLUSIONS

Surgery provided encouraging survival outcomes for clinical T4 NSCLC based on the 8th edition of classification. The nodal status and R-status were significant prognostic factors for postoperative survival.

Validation Study of the International Association for the Study of Lung Cancer Histologic Grading System of Invasive Lung Adenocarcinoma

INTRODUCTION

A histologic grading system for invasive lung adenocarcinoma (ADC) has been proposed by the International Association for the Study of Lung Cancer (IASLC) Pathology Committee in June 2020. This study evaluated the prognostic value of the IASLC histologic grading system (the IASLC system) in a large Japanese cohort.

METHODS

We performed comprehensive histologic subtyping using the semiquantitative estimation of five major patterns and complex glandular patterns in patients with a completely resected lung ADC and determined the histologic grade using the IASLC system. Concordance index and receiver-operating characteristic curves were used to evaluate the clinical utility of the IASLC system for recurrence and death; the comparison was performed with the architectural-pattern system (the Arch system) and the grading system on the basis of the two most predominant patterns (the Sica's system).

RESULTS

Of 1002 patients with invasive ADC, 235 had recurrent disease and 166 died of lung cancer. The concordance index and area under the curve of the IASLC system were 0.777 and 0.807 for recurrence and 0.767 and 0.776 for death, respectively. These were similar to those of the Arch system (0.763 and 0.796 for recurrence, 0.743 and 0.755 for death) and the Sica's system (0.786 and 0.814 for recurrence, 0.762 and 0.773 for death).

CONCLUSIONS

We reported that the IASLC system for invasive lung ADC has prognostic significance by evaluating a large Japanese cohort. We believe that the IASLC grading system will provide physicians with better information for postsurgery treatment.

Lung cancer and epithelial-mesenchymal transition

Lung cancer (LC) is a leading cause of cancer-related death worldwide. Epithelial-mesenchymal transition (EMT) is a well-known phenomenon that promotes the invasive and metastatic capabilities of LC. Especially, EMT is assumed to be a pivotal mechanism for tumor cell invasion and metastasis, thereby limiting the efficacy of surgery and medical treatments, resulting in poor patient prognoses. Thus, the elucidation and reversal of EMT could provide changes in therapeutic strategies for LC. To overcome the limitations of currents treatment regimens for LC, it is important for surgeons to be familiar with this complex tumor characteristic. In this review, the activating signaling pathways underlying EMT and the associated tumor phenotypes are briefly described.

Efficacy of three-dimensional computed tomography volumetry for recipients in downsizing oversized grafts in brain-dead donor lung transplantation

Objective

Brain-dead donor lung transplantation frequently requires reduction in the size of oversized lung grafts for patients with a small chest cavity. We focused on the role of three-dimensional computed tomography (3D-CT) volumetry for recipients on downsizing oversized lung grafts.

Methods

We performed 53 brain-dead donor bilateral lung transplantations, including 15 lobar lung transplants (Lobar group) and 38 standard lung transplants with full-sized grafts (Full group), between December 2010 and December 2018. Recipient chest volume before transplantation was measured using 3D-CT volumetry, and donor lung volume was evaluated by predicted total lung capacity. Post-transplant outcomes and pulmonary function were retrospectively compared between the groups.

Results

The ratio of the recipient chest volume to the donor lung volume was significantly lower in the Lobar group (0.42 ± 0.15) than in the Full group (0.77 ± 0.30, P < 0.01). The calculated size matching between the donor and recipient after downsizing the grafts was significantly correlated to the ratio of the recipient chest volume to the donor lung volume (Spearman r = 0.69; P < 0.01). Early post-transplant outcomes did not significantly differ between the groups. Although the Full group showed slightly better pulmonary function after transplantation, the 1-, 3-, and 5-year overall survival rates were similar to the Lobar group (100%, 93%, and 81% in the Lobar group vs. 92%, 78%, and 70% in the Full group; P = 0.50).

Conclusions

Brain-dead donor lobar lung transplantation showed favorable post-transplant outcomes. The assessment of recipient chest cavity volume using 3D-CT volumetry may help surgeons precisely downsize oversized lung grafts prior to transplantation.

Native lung complications after living-donor lobar lung transplantation

BACKGROUND

Living-donor lobar lung transplantation (LDLLT) is viable for critically ill patients in situations of donor shortage. Because it is sometimes difficult to find 2 ideal living donors with suitable graft sizes, we developed native lung-sparing procedures, including single LDLLT and native upper lobe-sparing LDLLT. This study aimed to investigate native lung complications (NLCs) in native lung-sparing LDLLT.

METHODS

Between April 2002 and March 2019, 92 LDLLTs and 124 cadaveric lung transplantations (CLTs) were performed at the Kyoto University Hospital. Our prospectively maintained database and clinical records were reviewed to compare NLCs among recipients who underwent native lung-sparing LDLLT (n = 21) with those among recipients who underwent single CLT (n = 61).

RESULTS

Among 21 recipients who underwent native lung-sparing LDLLT, 11 NLCs occurred in 8 recipients. No fatal NLC was noted; however, 2 required surgical intervention. Post-transplant survival was not significantly different between native lung-sparing LDLLT recipients with NLCs and those without NLCs. The incidence of NLCs was comparable between native lung-sparing LDLLT recipients and single CLT recipients (8/21 vs 26/61, p = 0.80); however, NLCs occurred significantly later in LDLLT recipients than in CLT recipients (median: 665 vs 181.5 days after transplantation, p = 0.014).

CONCLUSIONS

NLCs after native lung-sparing LDLLT had favorable outcomes. Therefore, native lung-sparing LDLLT is a useful treatment option for severely ill patients who cannot wait for CLT. However, it is important to recognize that NLCs may occur later in LDLLT than in CLT.

Prognostic significance of cribriform adenocarcinoma of the lung: validation analysis of 1,057 Japanese patients with resected lung adenocarcinoma and a review of the literature

Background

Cribriform-predominant adenocarcinoma of the lung (Cribri-ADC) is a recently described tumor growth pattern. However, its prognostic impact has not been clearly determined. We analyzed the data of a series of 1,057 Japanese patients with resected lung adenocarcinoma to identify the clinical significance of Cribri-ADC.

Methods

Cribriform pattern (Cribri-p) is defined as invasive back-to-back fused tumor glands with poorly formed glandular spaces or invasive tumor nests comprising tumors cells that produced glandular lumina. We investigated the correlations of Cribri-p and Cribri-ADC with clinicopathological factors as well as disease-free survival (DFS) and overall survival (OS).

Results

Cribri-p was present in 217 patients (20.5%) and Cribri-ADC was determined in 25 patients (2.4%). Cribri-p was associated with larger tumor size, pleural invasion, vascular invasion, lymphatic invasion, and spreading through air spaces (STAS) (all, P<0.0001). Cribri-ADC was associated with younger age (P=0.019), vascular invasion (P=0.0025), STAS (P<0.0001), and ALK rearrangement (P=0.012). The DFS curve of patients with Cribri-ADC was identical to that of patients with solid adenocarcinoma; however, the OS curve was located between that of patients with papillary and acinar adenocarcinoma. Of the 10 patients who had tumor recurrences, eight had EGFR mutations or ALK rearrangement, six of whom achieved relatively long survival (median, 64.6, range, 37.4–113 months) following treatment with tyrosine kinase inhibitors (TKIs). In multivariate analysis, Cribri-ADC was not an independent prognostic factor of either recurrence or death.

Conclusions

Cribri-ADC is associated with a higher risk of recurrence; however, most patients can be successfully treated with TKIs.

Randomized Phase III Study of Irinotecan Plus Cisplatin Versus Etoposide Plus Cisplatin for Completely Resected High-Grade Neuroendocrine Carcinoma of the Lung: JCOG1205/1206

PURPOSE

To verify the superiority of irinotecan plus cisplatin over etoposide plus cisplatin as postoperative adjuvant chemotherapy for patients with pathologic stage I-IIIA, completely resected, high-grade neuroendocrine carcinoma (HGNEC) of the lung.

METHODS

This was a randomized, open-label, phase III study on patients with completely resected stage I-IIIA HGNEC of the lung. They were randomly assigned to receive either etoposide (100 mg/m², days 1-3) plus cisplatin (80 mg/m², day 1) or irinotecan (60 mg/m², days 1, 8, 15) plus cisplatin (60 mg/m², day 1) up to four cycles. The primary end point was relapse-free survival (RFS) in the intention-to-treat population. This trial was registered with the Japan Registry of Clinical Trials (jRCTs031180216).

RESULTS

Between April 2013 and October 2018, 221 patients were enrolled (etoposide plus cisplatin arm, 111 patients; irinotecan plus cisplatin arm, 110 patients). In the second interim analysis, early termination of the trial was recommended because of futility. At a median follow-up of 24.1 months, the 3-year RFS was 65.4% for etoposide plus cisplatin and 69.0% for irinotecan plus cisplatin, with a hazard ratio of 1.076 (95% CI, 0.666 to 1.738; one-sided log-rank P = .619). Grade 3-4 adverse events were more frequent in the etoposide plus cisplatin arm, with febrile neutropenia (20% of 109 patients v 4% of 107 patients) and neutropenia (97% v 36%) being the most common. Meanwhile, grade 3-4 anorexia (6% v 11%) and diarrhea (1% v 8%) were more frequently observed in the irinotecan plus cisplatin arm.

CONCLUSION

Irinotecan plus cisplatin is not superior to etoposide plus cisplatin for improving RFS in patients with completely resected HGNEC; thus, etoposide plus cisplatin remains the standard treatment.

Prolonged air leak after reoperative pulmonary resection (with prior ipsilateral chest surgery)

Reoperative pulmonary resection (with prior ipsilateral chest surgery) has been reported to be associated with a high rate of postoperative complications. The objective of this study was to evaluate prolonged air leak (PAL) after reoperative pulmonary resections. We conducted a single-centre retrospective analysis on 100 consecutive patients undergoing ipsilateral reoperative pulmonary resection at our institution between March 2012 and February 2020. We investigated the incidence of PAL after reoperative pulmonary resections in comparison to that after first operations and analysed potentially relevant factors of PAL after reoperations. After reoperations, the incidence of PAL was 24%. The incidence of PAL after reoperations was significantly higher than that after first operations (P < 0.01). On multivariable analysis, anatomical resection (P = 0.03) and thoracotomy approach (P = 0.02) were found to be significant factors associated with the occurrence of PAL, and age was a significant factor associated with chest tube duration (P < 0.01) and length of hospital stay (P < 0.01) after reoperative pulmonary resection. Our study identified significant risk factors of PAL after reoperative pulmonary resections, which would be an important step towards improved management of patients undergoing reoperative pulmonary resections.

Tranilast Inhibits TGF-β1-induced Epithelial-mesenchymal Transition and Invasion/Metastasis via the Suppression of Smad4 in Human Lung Cancer Cell Lines

BACKGROUND/AIM

Transforming growth factor β1 (TGF-β1) is an important epithelial-mesenchymal transition (EMT) activator that regulates the expression of E-cadherin and vimentin through Smad signalling. Tranilast is an anti-allergic drug that inhibits TGF-β1, and is used in the treatment of keloids and hypertrophic scars. We investigated whether tranilast inhibits TGF-β1-induced EMT and invasiveness in human non-small cell lung cancer cell lines.

MATERIALS AND METHODS

We examined the effects of tranilast treatment on EMT markers, TGF-β1/Smad signalling, and cell invasiveness in A549 and PC14 cells. Tumours from a mouse orthotopic lung cancer model with or without tranilast treatment were also immunohistochemically evaluated.

RESULTS

Tranilast increased E-cadherin expression via Smad4 suppression and inhibited cell invasion in TGF-β1-stimulated cells. Tranilast treatment of the in vivo mouse model reduced the pleural dissemination of cancer cells and suppressed vimentin and Smad4 expression.

CONCLUSION

Tranilast inhibited TGF-β1-induced EMT and cellular invasion/metastasis by suppressing Smad4 expression in cancer cells.

Large nest micropapillary pattern of lung adenocarcinoma has poorer prognosis than typical floret pattern: analysis of 1,062 resected tumors

Background

A micropapillary pattern (MP-p) is related to poor prognosis in patients with lung adenocarcinoma (L-ADC). In 2015, the WHO defined the MP-p as "papillary tufts forming florets that lack fibrovascular cores and may appear detached from alveolar walls"; however, the sizes of tumor clusters in air space were not mentioned in this classification.

Methods

We evaluated the MP-p dividing the cluster sizes in the air space by reviewing 1,062 cases of resected L-ADCs. We classified MP-p into two types according to cluster size as follows: typical floret MP-p, tumors with small-to-medium-sized clusters (1-20 tumor cells); and large nest MP-p, tumors with large-sized clusters (>20 tumor cells, large nest). We then recorded the frequency of each type and investigated the association between the MP-p type and clinicopathological factors.

Results

Twenty-nine percent of L-ADCs (n=308) were MP-p-positive. Typical floret MP-p and large nest MP-p were observed in 244 tumors (22.9%) and 64 tumors (6.0%), respectively. Only 7 additional micropapillary ADCs were detected when we reclassified ADCs in addition to large nest MP-p. Tumors with large nest MP-p showed the highest frequency of node metastasis and worse prognosis compared to those with typical floret MP-p and absent (P<0.001). In multivariate analysis, patients with L-ADC with typical floret MP-p and large nest MP-p showed a higher recurrence rate [hazard ratio (HR): 1.762 (type 1 vs. absent), HR: 2.450 (type 2 vs. absent)].

Conclusions

Large nest MP-p should be included in the original MP-p and recorded separately.

Randomized phase III study of irinotecan/cisplatin (IP) versus etoposide/cisplatin (EP) for completely resected high-grade neuroendocrine carcinoma (HGNEC) of the lung: JCOG1205/1206

9006

Background: In the WHO classification, small cell lung cancer (SCLC) and large cell neuroendocrine carcinoma (LCNEC) are considered as high-grade neuroendocrine carcinoma (HGNEC) of the lung. Although there were no randomized trials evaluating adjuvant chemotherapy for patients (pts) with resected HGNEC, EP was considered to be a standard regimen for this population. A phase III study showed the superiority of IP to EP in pts with extensive stage SCLC (JCOG9511). Methods: Pts with completely resected HGNEC were randomized in a 1:1 ratio to receive either etoposide (100 mg/m2, days 1-3)/cisplatin (80 mg/m2, day 1) or irinotecan (60 mg/m2, days 1, 8, 15)/cisplatin (60 mg/m2, day 1), using the minimization method according to sex, pathologic stage, histology and institution. The primary endpoint was changed from overall survival (OS) to relapse-free survival (RFS) during the study period. We assumed a 3-year RFS of 59% of EP arm and 72% of IP arm (hazard ratio (HR) of 0.623). Planned sample size was 220 in total to give a power of 80% with a one-sided alpha of 5%, an accrual period of 6 years and a follow-up period of 3 years. Results: Between April 2013 and October 2018, 221 pts with a median age of 66 years, pathological stage I (54%), SCLC (53%), were randomly assigned to the EP arm (n = 111) or the IP arm (n = 110). In the second interim analysis, the predictive probability that IP would be superior to EP at the time of the primary analysis was 15.9%, which led to early termination of the trial. With a median follow-up of 24.1 months, 3-year RFS was 65.4% versus 69.0% with HR of 1.076 (95% CI, 0.666-1.738; log-rank test, one-sided P= 0.619). In the subgroup analyses of histology, 3-year RFS in SCLC was 65.2% versus 66.5% with HR of 1.029 (95% CI, 0.544-1.944), and 3-year RFS in LCNEC was 66.5% versus 72.0% with HR of 1.072 (95% CI, 0.517-2.222). Overall survival at 3 years was 84.1% versus 79.0% with HR of 1.539 (95% CI, 0.760-3.117). Proportions of treatment completion were 87.4% (EP) and 72.7% (IP). Incidences (EP/IP) of grade 3 or 4 febrile neutropenia (20.2/3.7%) or neutropenia (97.2/35.8%) were more common in EP. Grade 3 or 4 diarrhea (0.9/8.3%) or anorexia (6.4/11.1%) were more common in IP. One treatment-related death due to tracheal bleeding was observed in IP. Conclusions: This study failed to show the superiority of IP to EP in RFS for pts with completely resected HGNEC. EP is still a standard treatment for this population. Clinical trial information: UMIN000010298.

Is left-side DaVinci™ procedure challenging? Initial experiences of a single institute

OBJECTIVE

Among the standard techniques for anatomical lung cancer resection, left upper lobectomy has been regarded as challenging by thoracic surgeons. Thus, this study aimed to examine whether laterality of robot-assisted thoracoscopic procedures has any influence on the incidence of conversion to thoracotomy, operation time, amount of bleeding, and postoperative complications in the introduction phase of this procedure.

METHODS

The first consecutive 65 patients (right upper/middle/lower lobe with 31/3/15 cases, left upper/lower lobe with 10/6 cases) who underwent robot-assisted thoracoscopic lobectomy from December 2011 to April 2019 in Kyoto University were retrospectively reviewed.

RESULTS

Five cases were converted to open thoracotomy, including four for the left upper lobectomy and one for the right lower lobectomy (p = 0.011). The mean operation time was 229.9 ± 53.9 min (n = 12) and 192.8 ± 53.1 min (n = 48) for the left-sided and right-sided procedures, respectively (p = 0.043, conversion cases were not included). The mean bleeding amount was 29.1 ± 75.7 g (n = 49) and 136.8 ± 330.9 g (n = 16) for the right side and left side, respectively (p = 0.036). The mean operation time (min) for each lobe was as follows: 253.5 ± 73.9 for the left upper lobe (n = 6), 206.3 ± 41.3 for the left lower lobe (n = 6), 189.7 ± 51.3 for the right upper lobe (n = 31), 192.3 ± 57.5 for the right middle lobe (n = 3), and 199.9 ± 61.8 for the right lower lobe (n = 14).

CONCLUSION

Robot-assisted thoracoscopic surgery on the left side was associated with higher conversion rate, longer operation time, and more blood loss than that on the right side.

Survival outcomes of resection for pulmonary malignancies including non-small cell lung cancer and pulmonary metastasis after esophagectomy for esophageal carcinoma

OBJECTIVES

This study investigated survival outcomes of resection for pulmonary malignancies after esophagectomy for esophageal carcinoma, comparing non-small cell lung cancer and pulmonary metastases.

METHODS

We retrospectively reviewed consecutive patients who underwent resection for pulmonary malignancies after esophagectomy for esophageal carcinoma between 2009 and 2018. The overall survival and relapse-free survival rate were assessed using Kaplan-Meier analysis.

RESULTS

Eleven patients had non-small cell lung cancer and eight patients had pulmonary metastases from esophageal carcinoma. The 5-year overall survival rate was 92.9% in all patients with a median follow-up period of 50.4 (range: 9.1-130.2) months. While the 5-year overall survival rate was 100.0% in patients with non-small cell lung cancer, it was 85.7% in patients with pulmonary metastases from esophageal carcinoma. The 5-year relapse-free survival rate was 85.7% in patients with non-small cell lung cancer.

CONCLUSIONS

Our data suggest that resection for pulmonary malignancies after esophagectomy for esophageal carcinoma is associated with favorable survival outcomes and should be considered in selected patients.

Characteristics of incomplete endobronchial ultrasound-guided transbronchial needle aspiration cases

Backgrounds

The number of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) cases is increasing due to its less-invasiveness and usefulness. However, there are several unresolved issues, including the existence of incomplete cases and complications. This study aimed to investigate the frequency and diagnostic management of incomplete EBUS-TBNA cases.

Methods

Between July 2009 and December 2017, 424 patients underwent EBUS-TBNA for the diagnosis of suspected malignancy. Among them, we retrospectively reviewed the frequency, characteristics and diagnostic managements of incomplete cases of EBUS-TBNA.

Results

EBUS-TBNA was not completed in 16 patients (3.8%), all of whom underwent EBUS-TBNA cases under conscious sedation. The factors for incompleteness of EBUS-TBNA under conscious sedation were divided into two groups: impossibility to perform EBUS-TBNA under conscious sedation (n=8) and impossibility to perform safe needle biopsy (n=8). The former factor consisted of strong coughing reflex and insufficient sedation (n=5), frequent desaturation during EBUS-TBNA (n=2), and allergy to lidocaine (n=1), while the latter factor consisted of anatomical reasons (n=4), abundant blood flow in the target lesion (n=3), and invisibility of the target lesion due to airway deformation (n=1). Eventually, 10 out of 16 cases were histologically diagnosed as having malignancy by a surgical approach (n=5) and EBUS-TBNA under general anesthesia (n=5).

Conclusions

Although the number was small, we did note some incomplete cases of EBUS-TBNA under conscious sedation. In incomplete cases under conscious sedation, EBUS-TBNA under general anesthesia and other surgical approaches can be considered as additional options.