Salivary metabolomic biomarkers for non-invasive lung cancer detection

Identifying novel biomarkers for early detection of lung cancer is crucial. Non-invasively available saliva is an ideal biofluid for biomarker exploration; however, the rationale underlying biomarker detection from organs distal to the oral cavity in saliva requires clarification. Therefore, we analyzed metabolomic profiles of cancer tissues compared with those of adjacent non-cancerous tissues, as well as plasma and saliva samples collected from patients with lung cancer (n = 109 pairs). Additionally, we analyzed plasma and saliva samples collected from control participants (n = 83 and 71, respectively). Capillary electrophoresis-mass spectrometry and liquid chromatography-mass spectrometry were performed to comprehensively quantify hydrophilic metabolites. Paired tissues were compared, revealing 53 significantly different metabolites. Plasma and saliva showed 44 and 40 significantly different metabolites, respectively, between patients and controls. Of these, 12 metabolites exhibited significant differences in all three comparisons and primarily belonged to the polyamine and amino acid pathways; N1-acetylspermidine exhibited the highest discrimination ability. A combination of 12 salivary metabolites was evaluated using a machine learning method to differentiate patients with lung cancer from controls. Salivary data were randomly split into training and validation datasets. Areas under the receiver operating characteristic curve were 0.744 for cross-validation using training data and 0.792 for validation data. This model exhibited a higher discrimination ability for N1-acetylspermidine than that for other metabolites. The probability of lung cancer calculated using this model was independent of most patient characteristics. These results suggest that consistently different salivary biomarkers in both plasma and lung tissues might facilitate non-invasive lung cancer screening.

Impact of lymph node dissection on the efficacy of immune checkpoint inhibitors in patients with postoperative recurrence of non-small cell lung cancer

Background

The effect of lymph node dissection (LND) on the efficacy of immune checkpoint inhibitor (ICI) remains unclear. The purpose of this study was to examine the difference in the effect of ICI between patients with non-small cell lung cancer (NSCLC) according to the extent of LND performed in surgery prior to postoperative recurrence.

Methods

A total of 134 patients with postoperative recurrence (surgery group, n=26) or unresectable advanced lung cancer (non-surgery group, n=108) who were treated with ICIs between January 2016 and December 2022 were included for analysis. In the surgery group, 16 patients underwent systematic LND, whereas the remaining 10 patients underwent selective LND. Progression-free survival with ICI treatment (ICI-PFS) and overall survival (OS) were compared between the surgery and non-surgery groups and between the systematic and selective LND groups using the inverse probability of treatment weighting (IPTW) method to adjust for patient background characteristics.

Results

In the IPTW-adjusted analysis, the 2-year PFS rate with ICI treatment was 31.2% in the surgery group and 27.3% in the non-surgery group (P=0.19); the corresponding 2-year OS rates were 69.6% and 62.2%, respectively (P=0.10). In the surgery group, the 2-year PFS rates under ICI were 20.0% in the systematic LND group and 45.7% in the selective LND group (P=0.03).

Conclusions

IPTW-adjusted analysis indicated no difference in prognosis between patients with postoperative recurrence and those with advanced unresectable lung cancer. However, in patients with postoperative recurrence, the extent of LND was a significant predictor of ICI-PFS. These findings suggest that systematic LND may reduce the efficacy of ICI, indicating that preoperative ICI administration may be warranted.

Primary Lung Adenocarcinoma With ALK Gene Rearrangement Mostly Occupied by the Signet-Ring Cell Carcinoma Component: A Case Report

Primary lung carcinoma tumors possessing a signet-ring cell carcinoma (SRCC) component at varying proportions are rare, while those primarily composed of an SRCC component are much rarer. Reported here is a case of primary lung adenocarcinoma primarily composed of an SRCC component with a scant acinar component that developed in an 81-year-old male. Approximately 95% of the adenocarcinoma was occupied by an SRCC component that was shown to be diastase-resistant based on positive periodic acid-Schiff staining. Immunostaining for ALK and fluorescence in situ hybridization analysis (break-apart assay) showed the presence of an ALK gene rearrangement. Findings in this case indicated a primary lung adenocarcinoma with ALK gene rearrangement, in which an SRCC component accounted for approximately 95% of the tumor.

Surgical technique for preventing lung torsion after right upper and lower bilobectomy

In cases of right upper and lower bilobectomy, careful manipulation is required to avoid lung torsion, as only the right middle lobe remains in the right thoracic cavity. We report a case of successful right upper and lower bilobectomy with no torsion of the middle lobe. Our technique prevents postoperative lung torsion by fixing the lung to the chest wall and pericardial fat with silk threads. In situations where lung torsion is a concern after lung resection, fixing the remaining lungs with silk thread is effective in preventing lung torsion.

Significance of very-low-voltage coagulation plus coverage with polyglycolic acid sheet after bullectomy for primary spontaneous pneumothorax

BACKGROUND

The purpose of this study was to clarify the efficacy of the combination of low-voltage coagulation plus staple line coverage with a polyglycolic acid sheet after bullectomy for primary spontaneous pneumothorax to prevent a postoperative recurrence.

METHODS

A total of 143 patients who underwent bullectomy for primary spontaneous pneumothorax between January 2014 and December 2019 were enrolled in this study. We classified the patients into two groups based on additional procedures after bullectomy, namely, low-voltage coagulation for the margin of the staple line plus coverage with a polyglycolic acid sheet (Group A) and staple line coverage with a polyglycolic acid sheet alone (Group B). We evaluated perioperative factors and recurrence-free survival after surgery in the two groups.

RESULTS

Nine patients in Group B developed postoperative recurrences. In contrast, there was no postoperative recurrence in Group A. According to the Kaplan-Meier curves, the 2-year recurrence-free survival rates of the patients were 100% and 90.3%, in Group A and Group B, respectively. The log-rank test showed a significant difference between the two groups (p = 0.031).

CONCLUSION

Low-voltage coagulation for the margin of a staple line plus coverage with a polyglycolic acid sheet is a useful option as an additional technique after bullectomy for primary spontaneous pneumothorax to prevent a postoperative recurrence.

Intrathoracic lipoma in the horizontal fissure of the right lung: a case report

Lipomas are benign tumors that originate from mesenchymal tissue, such as subcutaneous tissue. Intrathoracic lipomas are rare, and they can occur in the chest wall, mediastinum and bronchi. In the present case, the patient had an intrathoracic lipoma that was located in the horizontal fissure of the right lung. Retrospective review of chest radiographs taken at a previous health checkup confirmed that the tumor was growing. The patient had no symptoms, and computed tomography and magnetic resonance imaging suggested that the tumor was a hamartoma. The tumor was resected by video-assisted thoracic surgery, and was diagnosed by pathological analysis as an intrathoracic lipoma consisting of no atypical fats.

Comparative analysis of the results of video-assisted thoracic surgery lobectomy simulation using the three-dimensional-printed Biotexture wet-lung model and surgeons' experience

OBJECTIVES

We performed a comparative analysis of the performance of video-assisted thoracic surgery (VATS) lobectomy simulation using three-dimensional-printed Biotexture lung models by surgeons classified according to their level of expertise. The aim of this study was to investigate the association between surgeons' experience and time to complete the VATS lobectomy simulation.

METHODS

Participants were divided into 3 groups: group A included those who had no experience of actual VATS lobectomy (n = 11), group B included those who had performed 5-10 VATS lobectomies (n = 12) and group C included those who had performed >100 VATS lobectomies (n = 6). Their performances were assessed based on total procedure time, duration to the exposure of the vessels, ligation of the arteries and stapling of the fissures. After the simulation, a questionnaire survey was performed.

RESULTS

The median total procedure time was significantly shorter in the group of surgeons with more experience (A vs B, P < 0.001; B vs C, P = 0.034; A vs C, P < 0.001). Regarding 'the exposure of all the vessels to be resected' and 'ligation of the arteries', group B completed these steps in less time than group A (P = 0.024 and P = 0.012, respectively). In the questionnaire, all groups answered that this simulation was useful for novices to improve their skills.

CONCLUSIONS

Although time to complete the VATS lobectomy simulation is only a part of evaluation points for real skills, this model can facilitate basic skill acquisitions for novices.

Sialadenoma Papilliferum of the Bronchus: An Unrecognized Bronchial Counterpart of the Salivary Gland Tumor With Frequent BRAF V600E Mutations

Sialadenoma papilliferum (SP) is a rare benign tumor of the salivary glands, and only 3 unequivocal cases of SP arising in the bronchus have been reported. We herein describe the histomorphologic and molecular features of 4 bronchial SP cases and discuss the differential diagnosis of this entity and the relationship with its clinicopathologic mimics, in particular, glandular papilloma and mixed squamous cell and glandular papilloma (GP/MP). We encountered 2 male and 2 female patients with bronchial SP (mean: 66.8 y old). All 4 tumors arose in the central bronchus and were characterized by a combination of surface exophytic endobronchial papillary proliferation and a submucosal multicystic component with complex architecture. The neoplastic epithelium consisted predominantly of nonciliated stratified columnar cells with ciliated, squamous, and mucinous cells present focally. While 2 tumors (50%) harbored a BRAF V600E mutation by molecular and immunohistochemical analysis, similar to GP/MP, no KRAS, HRAS, AKT1, or PIK3CA mutations were detected in any of the cases. Two patients were treated with limited resection, while 2 patients underwent lobectomy based on the diagnosis of adenocarcinoma or possible squamous cell carcinoma in situ in the preoperative biopsy. All survived without recurrence or metastasis for 23 to 122 months after treatment. SP can develop in the central bronchus as the bronchial counterpart of the salivary gland tumor and should be considered in the differential diagnosis of endobronchial tumors. In addition, some histologic resemblance and frequent BRAF V600E mutation raise the possibility of SP and GP/MP being on the same disease spectrum.

Clinical usefulness of the 3-tier classification according to the proportion of morphological patterns for patients with pathological stage I invasive lung adenocarcinoma

OBJECTIVES

We classified pathological stage I invasive lung adenocarcinomas according to our 3-tier classification, which was based on the proportion of invasive morphological patterns as follows: (1) patients with each predominant subtype, (2) those with a minor histological subtype, even not the predominant subtype and (3) those without each invasive component. We aimed to evaluate the classification's clinical impact in survival, recurrence, malignant grade, and epidermal growth factor receptor (EGFR) mutational status.

MATERIALS AND METHODS

A total of 1,269 patients with p-stage I lung adenocarcinoma underwent curative surgical resection between January 2008 and December 2017. Of these, 620 patients (48.9%) met the inclusion criteria of this study.

RESULTS

Postoperative recurrence was observed in 81 patients (13.1%). Multivariate analysis showed that vascular invasion (hazard ratio, 2.61; p < 0.001) and p-stage IB (hazard ratio, 2.19; p = 0.001) were significantly associated with an unfavorable RFS, while the presence of acinar component (hazard ratio, 1.64; p = 0.052) or solid component (hazard ratio, 1.60; p = 0.074) were marginally significant. The presence of lepidic or papillary component and the absence of acinar or solid component significantly correlated with an increased proportion of lung adenocarcinomas harboring EGFR mutations.

CONCLUSION

In patients with p-stage I invasive lung adenocarcinoma, it is beneficial to use not only the predominant subtype but analyzing the extent of each histological component based on our classification to predict patient prognoses and form appropriate postoperative follow-up methods.

F-18 fluorodeoxyglucose uptake in lymph nodes and sonographic features on endobronchial ultrasonography predict lymph node metastasis in lung cancer patients

Background

Sonographic findings of lymph nodes on endobronchial ultrasonography (EBUS) images have been reported to be useful to predict lymph node metastasis (LNM) in lung cancer patients. F-18 fluorodeoxyglucose (FDG) uptake in lymph nodes was also found to be useful. In this study, we aimed to clarify whether a combination of sonographic features and maximum standardized uptake values of lymph nodes (LN-SUVmax) is useful for predicting LNM in lung cancer patients.

Methods

From January 2014 to December 2019, a total of 147 lymph nodes from 104 patients with lung cancer, who underwent preoperative EBUS and FDG-positron emission tomography (PET)/computed tomography (CT) followed by surgery were retrospectively assesses. The characteristics of the patients, LN-SUVmax, and sonographic findings of lymph nodes were reviewed. Predictive factors associated with LNM were identified using the logistic regression model.

Results

The average size of the lymph nodes was 8.55 (range, 3–22) mm and the average LN-SUVmax was 5.36 (range, 1.79–31.19). The prevalence of nodal metastasis was 26/147 (17.4%), including 22 in mediastinal lymph nodes and 4 in hilar lymph nodes. Multivariate analysis demonstrated four independent predictive factors for LNM; size, round or oval shape, absence of a central hilar structure, and LN-SUVmax. The optimal cutoff value for lymph node size and LN-SUVmax were 10 mm and 6.00, respectively. By combinating of the two modalities, we obtained the results with sensitivity of 76.9%, specificity of 95.1% and accuracy of 93.2%.

Conclusions

A combination of sonographic findings and LN-SUVmax showed a higher diagnostic rate of LNM than either modality alone in lung cancer patients.

Prognostic Significance of Ground-Glass Opacity Components in 5-Year Survivors With Resected Lung Adenocarcinoma

BACKGROUND

Reports on the prognosis for 5-year survivors with lung adenocarcinoma after resection are sparse. This study aimed to identify factors associated with overall survival (OS) and cancer-specific survival (CSS) for 5-year survivors with completely resected lung adenocarcinoma, and to determine whether preoperative imaging factors, including the presence of ground-glass opacity (GGO) components, affect late recurrence in long-term survivors.

METHODS

Complete resection of lung adenocarcinoma was performed for 1681 patients between January 2000 and December 2013. Of these patients, 936 who survived 5 years or longer after surgery were identified, and factors associated with OS and CSS were determined using the Cox proportional hazard model.

RESULTS

Multivariable analysis demonstrated that lymph node metastasis (p < 0.01) and absence of GGO components (p < 0.01) were independently associated with OS and CSS for the 5-year survivors. The absence of GGO components was significantly associated with OS (p < 0.01) and CSS (p < 0.01) also for the 5-year survivors with stage 1 disease (n = 782) and for the 5-year survivors without recurrence (n = 809). The incidence of recurrence anytime during the 10-year postoperative follow-up period differed significantly between the 5-year survivors with and without GGO components.

CONCLUSIONS

The absence of GGO components was significantly associated with an unfavorable prognosis for the 5-year survivors with completely resected lung adenocarcinoma regardless whether they had recurrences not.

Prognostic impact of solid-part tumour volume doubling time in patients with radiological part-solid or solid lung cancer

OBJECTIVES

The measurement of part-solid and whole tumour sizes in patients with non-small-cell lung cancer (NSCLC) using computed tomography (CT) has been widely accepted for assessing clinical outcomes. Although the volume doubling time (VDT) of a tumour is useful for distinguishing high-risk nodules from low-risk ones, it remains to be clarified whether separate calculation of whole-tumour VDT and solid-part tumour VDT (SVDT) greatly affects the survival rate of patients with radiologically node-negative part-solid or solid NSCLC.

METHODS

The study included 258 patients with NSCLC who had radiologically node-negative, part-solid or solid tumours and who had at least 2 preoperative CT scans taken more than 30 days apart followed by radical lobectomy and systemic lymph node dissection between January 2012 and December 2015. Univariable and multivariable analyses of recurrence-free survival were performed using the Cox proportional hazards regression model.

RESULTS

The mean whole-tumour VDT and SVDT were 375 and 458 days, respectively. Multivariable analyses demonstrated that whole-tumour VDT (P = 0.003), SVDT (P < 0.001), solid-part tumour size, whole-tumour size and comorbidities significantly affected the recurrence-free survival. Using the receiver operating characteristic curve, the cut-off value of the SVDT for recurrence was 215 days, and the 5-year recurrence-free survival rates for patients with SVDT >215 days and those with SVDT <215 days were 85.7% and 43.0%, respectively (P < 0.001).

CONCLUSION

The calculation of SVDT in patients with node-negative, part-solid or solid NSCLC is highly useful for predicting postoperative survival outcomes.

Ubiquitin C-terminal hydrolase-L1 has prognostic relevance and is a therapeutic target for high-grade neuroendocrine lung cancers

High-grade neuroendocrine lung cancer (HGNEC), which includes small cell lung cancer (SCLC) and large cell neuroendocrine carcinoma (LCNEC) of the lung is a rapidly proliferating, aggressive form of lung cancer. The initial standard chemotherapeutic regimens of platinum doublets are recommended for SCLC and have been frequently used for LCNEC. However, there are currently no molecularly targeted agents with proven clinical benefit for this disease. The deubiquitinating enzyme ubiquitin C-terminal hydrolase-L1 (UCHL1) is a neuroendocrine cell-specific product that is known as a potential oncogene in several types of cancer, but little is known about the biological function of UCHL1 and its therapeutic potential in HGNEC. In this study, we found that preclinical efficacy evoked by targeting UCHL1 was relevant to prognosis in HGNEC. UCHL1 was found to be expressed in HGNEC, particularly in cell lines and patient samples of SCLC, and the combined use of platinum doublets with selective UCHL1 inhibitors improved its therapeutic response in vitro. Immunohistochemical expression of UCHL1 was significantly associated with postoperative survival in patients with HGNEC and contributed towards distinguishing SCLC from LCNEC. Circulating extracellular vesicles (EV), including exosomes isolated from lung cancer cell lines and serum from early-stage HGNEC, were verified by electron microscopy and nanoparticle tracking analysis. Higher levels of UCHL1 mRNA in EV were found in the samples of patients with early-stage HGNEC than those with early-stage NSCLC and healthy donors' EV. Taken together, UCHL1 may be a potential prognostic marker and a promising druggable target for HGNEC.

Epidermal growth factor receptor mutation subtype has differential effects on adjuvant chemotherapy for resected adenocarcinoma pathological stages II-III

The aim of the present study was to investigate epidermal growth factor receptor (EGFR) mutations as a prognostic factor for postoperative patients with positive EGFR mutations treated with postoperative platinum-based adjuvant chemotherapy (PBAC), and whether two common EGFR mutations exhibit different responses to PBAC. A total of 110 patients who underwent complete surgical resection were enrolled, and overall survival (OS) and disease-free survival (DFS) were investigated based on EGFR mutation status and PBAC. The 3 year OS rate in patient groups were as follows: Patients with EGFR mutations (MT) undergoing PBAC, 89.3%; MT patients without PBAC, 83.3%; wild-type (WT) patients with PBAC, 82.3%; and WT patients without PBAC, 62.2%. Statistically significant differences were observed between WT patients based on PBAC (P=0.026). No statistically significant differences were observed between MT patients with PBAC and MT patients without PBAC. On the basis of mutation subtypes, the 3 year OS rate of patient groups were as follows: Patients with in-frame deletions in exon19 (19 del) with PBAC, 92.3%; patients with 19 del without PBAC, 85.7%; patients with the point mutation L858R inexon21 (21L858R) with PBAC, 86.7%; and patients with 21L858R without PBAC, 81.5%; the respective 3-year DFS rates were 53.8, 14.3, 40.2 and 26.9%. Statistically significant differences were observed in the DFS rates in 19 del patients, which was dependent on PBAC (P=0.040). EGFR mutation-positive patients exhibited a decreased benefit from PBAC for increasing in survival rate compared with WT patients. It may be necessary to consider postoperative strategies based on EGFR mutations and their subtype in the future.

Computed Tomography Histogram Approach to Predict Lymph Node Metastasis in Patients With Clinical Stage IA Lung Cancer

BACKGROUND

Quantitative computed tomography (CT) histogram analysis of tumors is reported to help distinguish between invasive and less invasive lung cancers. This study aimed to clarify whether CT histogram analysis of tumors can be used to classify patients with clinical stage 0 to IA non-small cell lung cancer according to pathologic lymph node (pN) status.

METHODS

Predictive factors associated with pN metastasis were identified from the derivation dataset including 629 patients with clinical stage 0 to IA non-small cell lung cancer who underwent complete resection with lymph node dissection (surgeries between 2008 and 2013). The validation dataset including 238 patients (surgeries between 2014 and 2015) were subsequently reevaluated. Clinicosurgical factors, including CT histogram analysis of tumors (CT value percentiles 2.5, 25, 50, 75, and 97.5, skewness, and kurtosis) were assessed.

RESULTS

Seventy-three patients (12%) in the derivation cohort and 35 patients (15%) in the validation cohort had positive nodes. The pN status significantly affected survival in the entire population: 5-year overall survival of 93.1% vs 71.1% and 5-year disease-free survival of 85.9% vs 43.1% for negative vs positive (both P < .001). On multivariate analysis in the derivation cohort, the 75th percentile CT value (P < .001), age (P = .003), and comorbidities (P = .006) were significantly associated with pN metastasis. The area under the curve and the cutoff level of the 75th percentile CT value relevant to pN metastasis were 0.729 and 1.5 HU, respectively, and the threshold value provided accuracy of 71% for the validation cohort.

CONCLUSIONS

Histogram analysis of CT imaging metrics of tumors contributes to noninvasive prediction of pN metastasis in patients with clinical stage 0 to IA non-small cell lung cancer.

Pulmonary F-18 FDG uptake of non-tumor area in lung cancer patients to provide risk stratification in postoperative acute exacerbation of interstitial lung disease

e13165

Background: The incidence of lung cancer in patients with idiopathic pulmonary fibrosis (IPF) is higher than the general population. In IPF patients with lung cancer, postoperative acute exacerbation (AE) is considered a fatal comorbidity. This study aimed to investigate whether FDG-PET/CT can be used to assess the risk of postoperative AE of IPF and severe respiratory adverse events (SRAE),which are defined as grade 3a or more severe respiratory complications such as AE, bacterial pneumonia, empyema, and bronchial fistula based upon Clavian-Dindo classification. Methods: We identified 822 patients with lung cancer who had preoperative FDG-PET/CT and subsequent pulmonary resection from July 2012 to July 2018. We reviewed the patients’ clinical records and transferredthe preoperative FDG-PET/CT images of each patient to SynapseVincent system (Fujifilm Corporation, Tokyo, Japan) for measuring SUV value of the lung.Inevery case, both SUVmax of main tumor (tumor-SUVmax) and non-lung tumor part (NLT-SUVmax) were measured. Univariate and multivariate analyses were performed for exploring significant parameters associated with AE and SRAE. Results: The cohort in this study consisted of 460 men and 362 women (mean age 67.9 ± 10.1 years; range 23–87). SRAE was observed in 35 (4.2%) patients including those with AE (n = 16, 1.9%). NLT-SUVmax and presence of IPF on CT were the independent predictive factors for both AE and SRAE. The receiver operating characteristic (ROC) area under the curve (AUC) of significant factors associated with AE and SRAE was measured, and cut-off levels on ROC curves for significant parameters associated with AE and SRAE were 1.69 and 1.55, respectively. The risk rates for the incidence of AE and SRAE according to NLT-SUVmax and chest CT findings were 19.0 % and 30.2% of the patients with positive IPF on CT and NLT-SUV max ≥1.69. Conclusions: NLT-SUVmax was the independent predictor of the incidence of AE and SRAE for patients who underwent pulmonary resection. FDG/PET-CT can be used in routine clinical practice to identify high-risk individuals for AE who require careful and intensive observation after pulmonary resection and that can facilitate clinical decision-making.

Cytological differences between invasive and noninvasive or minimally invasive lung adenocarcinomas diagnosed in Japanese patients using needle biopsy specimens of pulmonary lesions ≤3 cm in diameter

Background

According to the WHO classification for lung cancer, adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) have a better prognosis than invasive adenocarcinoma (IAD). However, detecting the foci of invasion in lung adenocarcinomas radiologically remains difficult. The present study examined whether or not differences in the cytological characteristics between IAD and AIS or MIA (noninvasive or minimally invasive adenocarcinomas [NMIAD]) plays a role in the differential diagnosis.

Methods

Seventy surgical resection specimens of primary lung adenocarcinoma with preoperative cytology, in which several parameters were evaluated and assessed.

Results

The histopathological diagnoses of surgical resection specimens were AIS in 8, MIA in 31, IAD in 31 including lepidic adenocarcinoma in 9, and papillary adenocarcinoma in 22. NMIAD had a 100% 5‐year recurrence‐free survival (RFS), while IAD had an 82.8% 5‐year RFS. The numbers of tumor cells (at ×10 magnification in 10 fields) were 60.3 ± 40.5 in IAD and 39.8 ± 28.7 in NMIAD (P = 0.0017). A univariate analysis of cytological parameters revealed significant differences in large tumor cell clusters, three‐dimensional (3D) tumor cell clusters, and irregular nuclear contours between the two groups. The frequency of irregular nuclear contours continued to be significantly different according to a multivariate analysis.

Conclusion

Large or 3D tumor cell clusters and irregular nuclear contours may be important cytological factors for distinguishing IAD from NMIAD, with the latter being potentially more important for distinguishing between the two groups.

Clinicopathological characteristics and treatment strategies for young lung cancer patients

Background

The reported age-specific survival rates of lung cancer patients have been largely inconsistent. Management strategies for younger patients and treatment outcomes are not well characterized.

Methods

Out of the 4,697 lung cancer patients with treatment history at Tokyo Medical University Hospital between January 2000 and December 2014, 266 patients were <49 years of age. Patient characteristics were investigated, and the association of overall survival (OS) with age, sex, stage, and histological type were investigated.

Results

The 1-, 3-, and 5-year survival rates in the ≤49 years age group were 82.9%, 64.6%, and 57.0%. Among surgical cases, the survival rate of patients in the ≤49 years age group was significantly better than that in the 50-69 and ≥70 years age groups (P=0.29 and P<0.0001, respectively). In comparison with the OS rate with clinical stages, I, II, and III (but not with clinical stage IV) in the older than 50 years age group, the rates in the ≤49 years age group were better. The 1-, 3-, and 5-year OS rates of females were higher than those of their males. The 1-, 3-, and 5-year OS rates for lung adenocarcinoma patients were higher than that of lung non-adenocarcinoma patients.

Conclusions

Despite the higher proportion of advanced disease, the postoperative survival rate of the younger was higher than that of the older. Aggressive multimodality treatments, including surgery, are more feasible and effective for younger patients as compared with that in older patients.

Prognostic value of tumor solid-part size and solid-part volume in patients with clinical stage I non-small cell lung cancer

Background

This study aimed to predict the malignant potential of clinical stage I non-small cell lung cancer (c-I NSCLC) by semiautomatic three-dimensional (3D) volumetric measurement of a tumor (3D-data) and the axial computed tomography (CT) data derived from a 3D volumetric dataset (2D-data). The predictive performance was evaluated in terms of overall survival (OS), disease-free survival (DFS), and pathological invasive factors (positive lymphatic invasion, blood vessel invasion, pleural invasion, or lymph node metastasis).

Methods

We identified 252 patients (122 male; mean age, 68 years; range, 23-84 years) with c-I NSCLC who underwent high resolution CT and reconstruction of 3D imaging, followed by complete resection between January 2012 and December 2015. In this study, 2D-data including whole tumor size (WTS) and solid-part size (SPS) and 3D-data including whole tumor volume (WTV) and solid-part volume (SPV) acquired by a 3D volume rendering software were analyzed.

Results

The area under the receiver operating characteristic (ROC) curve for WTS, SPS, WTV, SPV relevant to recurrence was 0.667, 0.727, 0.654, and 0.751 while analyses of ROC curves revealed optimal WTS, SPS, WTV, and SPV cut-off values to predict recurrence of 2.48 cm, 2.03 cm, 3,258 mm³ and 1,889 mm³, respectively. The association between SPS and SPV was the coefficient of determination (R ²) =0.59. Multivariate analysis showed that SPV >1,889 mm³ (P=0.016) and male (P=0.041) were significant predictors of OS whereas SPV >1,889 mm³ (P=0.001), male (P=0.003), and the serum carcinoembryonic antigen value (P=0.041) were significantly correlated with DFS. SPS, SPV as well as the combination of SPS and SPV were all significantly correlated with the prediction of OS and DFS, and the incidence of pathological invasive factors.

Conclusions

SPV and the integrated use of SPS and SPV was highly beneficial for the prediction of postoperative prognosis in c-I NSCLC.

Predictive accuracy of lepidic growth subtypes in early-stage adenocarcinoma of the lung by quantitative CT histogram and FDG-PET

OBJECTIVES

The aim of this study was to analyze the accuracy of computed tomography (CT) and F-18 fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) to distinguish lepidic growth adenocarcinoma (LGA), including adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and lepidic-predominant adenocarcinoma, all of which have favorable survival outcomes, from the more aggressive and invasive non-LGA subtypes.

MATERIALS AND METHODS

We identified 225 patients with c-0/I adenocarcinoma of the lung who underwent PET/CT and 3DCT followed by complete resection. Maximum standardized uptake values (SUVmax) of FDG and several histogram parameters were analyzed. Histological grades were classified according to the predominant subtype (G1: lepidic; G3: micropapillary or solid; and G2: subtypes other than G1/G3).

RESULTS

The proportion of pathological invasive factors (lymphatic vessel involvement/blood vessel invasion/pleural invasion/lymph node metastasis) of patients with preinvasive adenocarcinoma, G1, G2, and G3 tumors were 0%, 3.6%, 48.0%, and 100%, respectively; p <  0.001). Multivariate analysis with CT-related parameters demonstrated that 75^th percentile CT attenuation value (75^th%, p <  0.001) and maximum CT attenuation value (maxCT, p =  0.009) were associated with incidence of non-LGA, whereas the value of SUVmax demonstrated a significant correlation (p <  0.001). When all patients were dichotomized according to ground-glass opacities (GGO)/solid-dominancy for CT maximum diameter, a significant correlation with non-LGA was shown in patients with solid-dominant tumor on SUVmax (p <  0.001) and with GGO-dominant tumor on 75^th% (p =  0.006) and maxCT (p =  0.007). The combination of one of the two significant histogram parameters and SUVmax revealed higher predictive performance for pathological high malignant features (positive pathological invasive factors, non-LGA, and the highly malignant subtype covering G2 with moderately or poorly-differentiated carcinoma and G3) than the individual use of either factor.

CONCLUSION

The 75^th%, maxCT, and SUVmax were highly useful in distinguishing LGA from non-LGA in c-0/I adenocarcinoma.

Transition Rate from EGFR-TKI to Cytotoxic Chemotherapy Patients with EGFR Mutation-positive Lung Adenocarcinoma

BACKGROUND/AIM

The transition rate from first-line epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) to cytotoxic chemotherapy (Ct) is poor. The prognosis according to treatment sequence and the reasons patients could not shift from first-line EGFR-TKIs to Ct were herein analyzed.

PATIENTS AND METHODS

Overall, 159 epidermal growth factor receptor mutation-positive adenocarcinoma patients were enrolled in this study.

RESULTS

The median survival times of EGFR-TKIs combined with Ct and EGFR-TKIs were 59.8 months and 22.5 months, respectively (p<0.001) and of patients who received EGFR-TKIs first and Ct first were 38.8 months and 66.4 months, respectively (p=0.016). The main reasons patients could not make the transition to Ct was worsening of performance status and patient's preference.

CONCLUSION

EGFR-TKIs and Ct lead to a good prognosis in EGFR mutation-positive adenocarcinoma patients. It is necessary to consider the timing when changing the treatment strategy before treatment options are limited.

Cost-Benefit Performance Simulation of Robot-Assisted Thoracic Surgery As Required for Financial Viability under the 2016 Revised Reimbursement Paradigm of the Japanese National Health Insurance System

PURPOSE

To discuss the cost-benefit performance (CBP) and establish a medical fee system for robotic-assisted thoracic surgery (RATS) under the Japanese National Health Insurance System (JNHIS), which is a system not yet firmly established.

METHODS

All management steps for RATS are identical, such as preoperative and postoperative management. This study examines the CBP based on medical fees of RATS under the JNHIS introduced in 2016.

RESULTS

Robotic-assisted laparoscopic prostatectomy (RALP) and robotic-assisted partial nephrectomy (RAPN) now receive insurance reimbursement under the category of use of support devices for endoscopic surgery ($5420 and $3485, respectively). If the same standard amount were to be applied to RATS, institutions would need to perform at least 150 or 300 procedures thoracic operation per year to show a positive CBP ($317 per procedure as same of RALP and $130 per procedure as same of RAPN, respectively).

CONCLUSION

Robotic surgery in some areas receives insurance reimbursement for its "supportive" use for endoscopic surgery as for RALP and RAPN. However, at present, it is necessary to perform da Vinci Surgical System Si (dVSi) surgery at least 150-300 times in a year in a given institution to prevent a deficit in income.

Prognostic factors for surgically resected non-small cell lung cancer with cavity formation

Background

Small pulmonary nodules have been detected frequently by computed tomography (CT). Lung cancers with cavity formation are also easily detected. There are a few reports focused on the cavity wall, although cancer cells exist along the cavity wall, not inside. We evaluated the impact of cavity wall thickness on prognosis and assessed the clinicopathological features in non-small cell lung cancer (NSCLC) with cavity formation.

Methods

Between 2005 and 2011, 1,313 patients underwent complete resection for NSCLC. Of these cases, we reviewed 65 patients (5.0%) diagnosed with NSCLC with cavity formation by chest CT. We classified the patients into three groups based on the maximum cavity wall thickness, namely, ≤4 mm (Group 1, 8 patients), >4 and ≤15 mm (Group 2, 33 patients), and >15 mm (Group 3, 24 patients).

Results

The number of patients with pathological whole tumor size >3 cm was 2 (25%) in Group 1, 17 (52%) in Group 2, and 23 (96%) in Group 3 (P<0.001). Cases with lymph node metastasis were 0 (0%) in Group 1, 5 (15%) in Group 2, and 10 (42%) in Group 3 (P=0.016). The 5-year overall survival (OS) rates were 100% in Group 1, 84.0% in Group 2, and 52.0% in Group 3, with significant differences between Group 1 and Group 3 (P=0.044) and between Group 2 and Group 3 (P=0.034). In univariate analysis, neither whole tumor size nor lymph node metastasis was a prognostic factor for OS (P=0.51, P=0.27). Only cavity wall thickness was a significant prognostic factor by multivariate analysis (P=0.009).

Conclusions

Maximum cavity wall thickness was an important prognostic factor in NSCLCs with cavity formation, comparable with other established prognostic factors.

Clinical applications of virtual navigation bronchial intervention

Background

In patients with bronchial tumors, we frequently consider endoscopic treatment as the first treatment of choice. All computed tomography (CT) must satisfy several conditions necessary to analyze images by Synapse Vincent. To select safer and more precise approaches for patients with bronchial tumors, we determined the indications and efficacy of virtual navigation intervention for the treatment of bronchial tumors.

Methods

We examined the efficacy of virtual navigation bronchial intervention for the treatment of bronchial tumors located at a variety of sites in the tracheobronchial tree using a high-speed 3-dimensional (3D) image analysis system, Synapse Vincent. Constructed images can be utilized to decide on the simulation and interventional strategy as well as for navigation during interventional manipulation in two cases.

Results

Synapse Vincent was used to determine the optimal planning of virtual navigation bronchial intervention. Moreover, this system can detect tumor location and alsodepict surrounding tissues, quickly, accurately, and safely. The feasibility and safety of Synapse Vincent in performing useful preoperative simulation and navigation of surgical procedures can lead to safer, more precise, and less invasion for the patient, and makes it easy to construct an image, depending on the purpose, in 5-10 minutes using Synapse Vincent. Moreover, if the lesion is in the parenchyma or sub-bronchial lumen, it helps to perform simulation with virtual skeletal subtraction to estimate potential lesion movement. By using virtual navigation system for simulation, bronchial intervention was performed with no complications safely and precisely.

Conclusions

Preoperative simulation using virtual navigation bronchial intervention reduces the surgeon's stress levels, particularly when highly skilled techniques are needed to operate on lesions. This task, including both preoperative simulation and intraoperative navigation, leads to greater safety and precision. These technological instruments are helpful for bronchial intervention procedures, and are also excellent devices for educational training.

Successful adjustment for self-expanding metallic stent migration using a flexible bronchoscope with two biopsy forceps technique

Although tracheobronchial stents are widely used for tracheal obstruction due to malignant or benign stenosis, stent migration has been reported as a major postoperative complication. A self-expandable metallic stent (SEMS) is more easily introduced compared with silicone stents. However, it is also difficult to remove or replace without complications. We report a new technique for successful SEMS adjustment using a flexible bronchoscope with two biopsy forceps.

Tumor volume determines the feasibility of cell-free DNA sequencing for mutation detection in non-small cell lung cancer

Next‐generation sequencing (NGS) and digital PCR technologies allow analysis of the mutational profile of circulating cell‐free DNA (cfDNA) in individuals with advanced lung cancer. We have now evaluated the feasibility of cfDNA sequencing for mutation detection in patients with non‐small cell lung cancer at earlier stages. A total of 150 matched tumor and serum samples were collected from non‐small cell lung cancer patients at stages IA–IIIA. Amplicon sequencing with DNA extracted from tumor tissue detected frequent mutations in EGFR (37% of patients), TP53 (39%), and KRAS (10%), consistent with previous findings. In contrast, NGS of cfDNA identified only EGFR,TP53, and PIK3CA mutations in three, five, and one patient, respectively, even though adequate amounts of cfDNA were extracted (median of 4936 copies/mL serum). Next‐generation sequencing showed a high accuracy (98.8%) compared with droplet digital PCR for cfDNA mutation detection, suggesting that the low frequency of mutations in cfDNA was not due to a low assay sensitivity. Whereas the yield of cfDNA did not differ among tumor stages, the cfDNA mutations were detected in seven patients at stages IIA–IIIA and at T2b or T3. Tumor volume was significantly higher in the cfDNA mutation‐positive patients than in the negative patients at stages T2b–T4 (159.1 ± 58.0 vs. 52.5 ± 9.9 cm³, P = 0.014). Our results thus suggest that tumor volume is a determinant of the feasibility of mutation detection with cfDNA as the analyte.

Correlation between whole tumor size and solid component size on high-resolution computed tomography in the prediction of the degree of pathologic malignancy and the prognostic outcome in primary lung adenocarcinoma

BACKGROUND

The presence of ground glass opacity (GGO) on high-resolution computed tomography (HRCT) is well known to be pathologically closely associated with adenocarcinoma in situ.

PURPOSE

To determine whether it is more useful to evaluate the whole tumor size or only the solid component size to predict the pathologic high-grade malignancy and the prognostic outcome in lung adenocarcinoma.

MATERIAL AND METHODS

Using HRCT data of 232 patients with adenocarcinoma who underwent curative resection, we retrospectively measured the whole tumor and solid component sizes with lung window setting (WTLW and SCLW) and whole tumor sizes with a mediastinal window setting (WTMW).

RESULTS

There was significant correlation between the WTLW and the measurements of pathological whole tumor (pWT) (r = 0.792, P < 0.0001). The SCLW and WTLW values significantly correlated with the area of pathological invasive component (pIVS) (r = 0.762, P < 0.0001 and r = 0.771, P < 0.0001, respectively). The receiver operating characteristics area under the curve for WTLW, SCLW, and WTMW used to identify lymph node metastasis or lymphatic or vascular invasion were 0.693, 0.817, and 0.824, respectively. Kaplan-Meier curves of disease-free survival (DFS) and overall survival (OS) were better divided according to SCLW and WTMW, compared with WTLW. Multivariate analysis of DFS and OS revealed that WTMW was an independent prognostic factor (HR = 0.72, 95% confidence interval [CI] = 0.58-0.90, P = 0.004 and HR = 0.74, 95% CI = 0.57-0.96, P = 0.022, respectively).

CONCLUSION

The predictive values of the solid tumor size visualized on HRCT especially in the mediastinal window for pathologic high-grade malignancy and prognosis in lung adenocarcinoma were greater than those of whole tumor size.

Association between high-resolution computed tomography findings and the IASLC/ATS/ERS classification of small lung adenocarcinomas in Japanese patients

OBJECTIVES

The detection rate of small pulmonary nodules has recently increased and new techniques have been developed to improve diagnostic yield. The IASLC/ATS/ERS classification demonstrated a difference in prognosis depending on the histological subtypes of lung adenocarcinoma. We evaluated the association between high-resolution computed tomography (HRCT) findings and the classification of these tumors.

METHODS

We reviewed the data of 220 lung adenocarcinoma (≤3 cm) patients who received complete resection with lymph node dissection in our hospital. From the HRCT findings, the tumors were classified into the following 3 categories: pure-solid nodules, part-solid nodules, or pure ground-glass opacity (GGO) nodules. Pathological invasion factor (PIF) was evaluated by the degree of blood vessel invasion, lymphatic permeation, and visceral pleural invasion.

RESULTS

The tumors were classified as pure GGO nodules in 16 patients, part-solid nodules in 91, and pure-solid nodules in 113 from the HRCT findings. Tumors were diagnosed as noninvasive or minimally invasive adenocarcinomas (NMIADs) in 44 patients, and invasive adenocarcinomas (IADs) in 176. Lymph node metastasis was present in 31 patients (14.1%) and PIF in 101 (45.9%). All pure-solid nodules were IADs with a high PIF frequency (75.2%) or with lymph node metastasis (26.5%). All pure GGO nodules were NMIADs or lepidic-predominant adenocarcinomas. Among the part-solid nodules, IAD was detected in 67.0% of the patients and PIF in 16.5%. The consolidation/tumor (C/T) ratio and consolidation size were associated with IAD (optimal cut-off values: 0.4 and 8mm, respectively) and PIF (0.8 and 15 mm, respectively).

CONCLUSIONS

The HRCT findings correlated with the IASLC/ATS/ERS classification and were useful for evaluating the histological nature of the tumors. Most pure-solid tumors had the potential for high-grade malignancy, including PIF and lymph node metastasis. For part-solid tumors, the C/T ratio and consolidation size were important for predicting PIF and for diagnosing IAD according to this classification.