Lung cancer after kidney transplantation: a 50-year experience at a single institution.

PURPOSE: To investigate the clinical characteristics of lung cancer that develops after kidney transplantation. METHODS: The clinical data of patients with lung cancer diagnosed after kidney transplantation were collected retrospectively. The medical records were extracted from our database. All patients underwent routine chest examination after kidney transplantation. RESULTS: In total, 17 lung tumors were detected in 15 (0.6%) of 2593 patients who underwent kidney transplantation at our institution. Eleven lung tumors were completely resected from a collective 10 patients (surgical group). The remaining five patients did not receive surgical treatment (nonsurgical group). The surgical group underwent wedge resection (n = 5), segmentectomy (n = 1), lobectomy (n = 3), and bilobectomy (n = 1). The pathological stages were 0 (n = 1), IA1 (n = 2), IA2 (n = 4), IA3 (n = 2), and IB (n = 1). The surgical group had a significantly better prognosis than the nonsurgical group. There were no perioperative complications related to kidney transplantation in either group. CONCLUSIONS: Routine chest examination would be useful for the early diagnosis and treatment of lung cancer after kidney transplantation. Moreover, surgical resection for early-stage lung cancer was associated with a better prognosis for kidney transplantation patients.

＜Editors' Choice＞ Learning curve of robotic lobectomy for lung malignancies by certified thoracic surgeons.

Video-assisted thoracic surgery (VATS) has become widespread in the last 20 years, followed by robot-assisted thoracic surgery (RATS). Few studies compared the learning curve between RATS lobectomy and conventional VATS. This study included 79 RATS lobectomy cases performed in our hospital from November 2015 to October 2019. To estimate the required number for learning, the cumulative sum method, which is to plot a value obtained by sequentially accumulating a difference from a mean value was applied. As a result, the median total operative time and the median console time for all cases were 167 minutes and 138 minutes, respectively. Firstly, for our team, 28 cases were estimated to be required for learning curve for RATS lobectomy. For individual, each surgeon might be learned in only 5 to 6 cases. By contrast, the number of cases for learning VATS lobectomy which was underwent by a 'single' surgeon from 2009 was estimated to be 35 cases. The time to dock from start operation (median 14 minutes) reached plateau in 18 cases, but the time after rollout was median of 18 minutes and there was no significant change from the beginning. In conclusion, RATS lobectomy might be a technique that could be learned in a small number of cases compared to VATS. The results of this study might be helpful for certified surgeons who tried to get started with RATS and for establishing a learning program.

Combined surgical therapy for pulmonary sequestration and aberrant artery from the abdominal aorta.

Pulmonary sequestration with feeding vessels from the abdominal aorta is relatively rare. A 56-year-old woman with chronic left thoracic pain was referred to our hospital. Computed tomography showed multiple pulmonary cysts in the left lung and an aberrant artery from the abdominal aorta. She was diagnosed with pulmonary sequestration. She underwent embolization of the aberrant artery and wedge resection of the sequestrated lung under indocyanine green guidance. The surgical treatment combining preoperative embolization of the artery and intraoperative indocyanine green-guided lung resection might be safe and minimally invasive for patients with lung sequestrations accompanied by feeding vessels from the abdominal aorta.

Thymic lipofibroadenoma accompanied with largish calcifications.

Thymic lipofibroadenomas are extremely rare; their radiological features have never been reported. We report the first case of a lipofibroadenoma with some largish calcifications mimicking a teratoma. A 28-year-old man had an anterior mediastinal tumor with some calcifications on preoperative computed tomography, which was suspected to be a mature teratoma and resected through robot-assisted thoracic surgery. This tumor had strands of epithelial cells separated by abundant fibrous stroma containing fat cells and was thus diagnosed as a lipofibroadenoma. He was well without any recurrence 6 months postoperatively. Largish calcifications on preoperative computed tomography make distinguishing between teratomas and lipfibroadenomas difficult.

Factors associated with changes in the 12-m stair-climbing time after lung lobectomy.

OBJECTIVE: Postoperative loss-of-exercise capacity is one of the main concerns for patients undergoing lung cancer surgery. This study was designed to identify the factors associated with loss-of-exercise capacity after lobectomy, using an easy surrogate measure: the 12-m stair-climbing time (SCt). METHODS: Ninety-eight patients undergoing lobectomy for suspected stage I lung cancer were prospectively enrolled. SCt and pulmonary function test were evaluated preoperatively as baseline and at 6 months postoperatively. At 6 months postoperatively, 20 patients dropped out. Loss-of-exercise capacity was defined as at least a 3.3% decline (lower quartile) in the estimated maximal oxygen uptake (VO2t: 43.06 - 0.4 × SCt). Factors associated with loss-of-exercise capacity were analyzed. RESULTS: Median (interquartile range) baseline SCt was 31.5 (28.2-36.7) s. Baseline SCt was not significantly associated with complications. At 6 months postoperatively, SCt increased by + 4.4 (+ 3.2, + 6.8) s in patients with loss-of-exercise capacity. Sex, smoking status, lobe, procedure, and forced expiratory volume in 1 s showed no significant association with loss-of-exercise capacity. In the multivariable logistic regression, older age (≥ 73 years) (odds ratio: 5.25, 95% confidence interval: 1.50-18.43, p = 0.010) and lower baseline diffusing capacity of the lung for carbon monoxide (< 75%) (odds ratio: 9.23, 95% confidence interval: 1.94-43.93, p = 0.005) were significantly associated with loss-of-exercise capacity. CONCLUSION: Age and the baseline diffusing capacity of the lung for carbon monoxide were identified as significant variables associated with variation of exercise capacity after lung cancer surgery, using pre- and postoperative SCt.

Well-differentiated fetal adenocarcinoma of the lung: positron emission tomography features and diagnostic difficulties in frozen section analysis-a case report.

BACKGROUND: Well-differentiated fetal adenocarcinoma (WDFA) of the lung is a rare disease that resembles fetal lung tubules. Most of previous reports concerning WDFA have focused on histological features, while there are few reports describing radiological features. In addition, there are no reports evaluating the difficulty of intraoperative diagnosis of WDFA with frozen section. We report a case of WDFA and review the radiological features of WDFA including the findings of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and assess the difficulty of intraoperative diagnosis with frozen section. CASE PRESENTATION: A chest radiography performed in a 20-year-old female revealed a mass in the hilum of the right lung. Computed tomography revealed a well-defined mass measuring 3.5 × 3.0 cm in diameter in the right upper lobe, whereas PET showed a high accumulation of FDG. The most likely diagnosis was clinical T2aN0M0 stage 1B non-small cell lung cancer. A right S3 segmentectomy was performed via thoracotomy, and a benign tumor that was possibly an adenoma was intraoperatively diagnosed based on frozen section analysis. The mass was a solid tumor measuring 2.9 × 2.5 cm in diameter. Microscopically, the tumor comprised abundant glands with single or double layers of nonciliated cells and bronchial structures resembling a fetal lung. Rounded morules of polygonal cells were frequently observed. Immunohistochemistry revealed that nuclei and cytoplasm of the tumor cell were positive for ß-catenin. Finally, the postoperative pathological diagnosis was well-differentiated fetal adenocarcinoma of the lung, and completion right upper lobectomy and mediastinal lymph node dissection were conducted 1 month after the initial segmentectomy. No residual tumor or lymph node metastasis was identified, and the final pathological stage was pT1cN0M0 stage 1A3. The patient did not wish to receive any adjuvant therapy. At the 1-year follow-up, no evidence of recurrence was noted. CONCLUSIONS: Here, we report a rare case of well-differentiated fetal adenocarcinoma of the lung that was difficult to diagnose based on radiological evaluations including FDG-PET and intraoperative diagnosis using frozen section analysis.

Current trends in thoracic surgery.

Thoracic surgery has evolved drastically in recent years. Although thoracic surgeons mainly deal with tumorous lesion in the lungs, mediastinum, and pleura, they also perform lung transplantation surgery in patients with end-stage lung disease. Herein, we introduce various major current topics in thoracic surgery. Minimally invasive surgical procedures include robot-assisted thoracic surgery and uniportal video-assisted thoracic surgery. Novel techniques for sublobar resection include virtual-assisted lung mapping, image-guided video-assisted thoracic surgery, and segmentectomy using indocyanine green. Three-dimensional (3D) computed tomography (CT) simulation consists of surgeon-friendly 3D-CT image analysis systems and new-generation, dynamic 3D-CT imaging systems. Updates in cadaveric lung transplantation include use of marginal donors, including donation after circulatory death, and ex vivo lung perfusion for such donors. Topics in living donor lobar lung transplantation include size matching, donor issues, and new surgical techniques. During routine clinical practice, thoracic surgeons encounter various pivotal topics related to thoracic surgery, which are described in this report.

Micro-computed tomography images of lung adenocarcinoma: detection of lepidic growth patterns.

Micro-computed tomography (µCT) provides extremely high-resolution images of samples and can be employed as a non-destructive inspection tool. Using µCT, we can obtain images comparable with microscopic images. In this work, we have attempted to take high-resolution images of the human lung using µCT. Compared to clinical high-resolution computed tomography (HRCT) images of living body (in-vivo imaging), we can obtain extremely high-resolution images by µCT of ex-vivo tissues (resected lungs) as three-dimensional data. The purpose of this study was to distinguish between areas of normal lung and lung cancer by µCT images in order to study the feasibility of cancer diagnosis using this novel radiological image modality. Ten resected human lungs containing primary cancer were fixed by Heitzman's methods to obtain high-resolution µCT images. After fixation of the lung, images of the specimens were taken by µCT between January 2016 and November 2017. The imaging conditions were tube voltage: 90 kV and tube current: 110 µA. To compare details of images gained by conventional HRCT and µCT, we measured the thickness of the alveolar walls of the normal lung area and the cancer area of which alveoli might be replaced by tumor cells, and compared their appearance by means of histopathological images. All the nodules were diagnosed as adenocarcinoma. The median whole tumor size was 18 mm (9 mm-24 mm). Each specimen was clearly divided into areas of normal alveolar wall and of thickened alveolar wall on µCT 'visually'. Median thickness of alveolar walls of the normal lung was 0.037 mm (0.034 mm-0.048 mm), and that of the cancer area was 0.084 mm (0.074 mm-0.094 mm); there was a statistically significant difference between both thicknesses by Student's t-test (P < 0.01). The area of thickened alveolar walls on µCT corresponded well with the area of microscopically lepidic growth patterns of adenocarcinoma. We found that µCT images could be correctly divided by alveolar walls into normal lung area and lung cancer area. Further detailed investigations with regard to µCT are needed to make comparable histological diagnoses using µCT images with conventional microscopic methods of pathological diagnoses.

Clinical application of a surgical navigation system based on virtual thoracoscopy for lung cancer patients: real time visualization of area of lung cancer before induction therapy and optimal resection line for obtaining a safe surgical margin during surgery.

BACKGROUND: We have developed a surgical navigation system that presents virtual thoracoscopic images using computed tomography (CT) image data, as if you are observing intra-thoracic cavity in synchronization with the real thoracoscopic view. Using this system, we made it possible to simultaneously visualize the 'area of lung cancer before induction therapy' and the 'optimal resection line for obtaining a safe surgical margin' as a virtual thoracoscopic view. We applied this navigation system in the clinical setting in operations for lung cancer patients with chest wall invasion after induction chemoradiotherapy. METHODS: The proposed surgical navigation system consisted of a three-dimensional (3D) positional tracker and a virtual thoracoscopy system. The 3D positional tracker was used to recognize the positional information of the real thoracoscope. The virtual thoracoscopy system generated virtual thoracoscopic views based on CT image data. Combined with these two technologies, patient-to-image registration was performed in two patients, and the results generated a virtual thoracoscopic view that was synchronized with the real thoracoscopic view. RESULTS: The operations were started with video-assisted thoracic surgery (VATS), and the navigation system was activated at the same time. The virtual thoracoscopic view was synchronized with the real thoracoscopic view, which also simultaneously indicated the 'area of lung cancer before induction therapy' and the 'optimal resection lines for obtaining a safe surgical margin'. We marked the optimal lines using an electric scalpel, and then performed lobectomy and chest wall resection with a sufficient surgical margin using these landmarks. Pathological examinations confirmed that the surgical margin was negative. No complications related to the navigation system were encountered during or after the procedures. CONCLUSIONS: Using this proposed navigation system, we could obtain a 'CT-derived virtual intra-thoracic 3D view of the patient' that was aligned with the thoracoscopic view during surgery. The accurate identification of areas of cancer invasion before induction therapy using this system might be a useful for determining optimal surgical resection lines.

Psoas muscle mass in patients undergoing lung cancer surgery: a prognostic difference between squamous cell carcinoma and adenocarcinoma.

BACKGROUND: Psoas muscle mass is a surrogate marker for sarcopenia: a depletion of skeletal muscle mass. This study was conducted to elucidate the prognostic significance of the psoas muscle index (PMI: cross-sectional area of the bilateral psoas muscle at the umbilical level on computed tomography/height2 [cm2/m2]) in patients undergoing surgery for lung squamous cell carcinoma (SCC) and lung adenocarcinoma (ADC). METHODS: One hundred and sixty-five patients with SCC and 556 patients with ADC who underwent R0 resection between 2007 and 2014 were reviewed for analysis. In SCC patients, the mean value (standard deviation) of the PMI was 6.15 (1.49) in men and 4.65 (1.36) in women. Among ADC patients, the PMI was 7.12 (1.60) in men and 5.29 (1.22) in women. Clinicopathological characteristics as well as the survival were evaluated. RESULTS: The PMI was associated with the age, body mass index (BMI), and serum albumin. In the multivariable Cox regression analysis, after adjusting for age, BMI, serum albumin, sex, pathological stage, and diffusing capacity for carbon monoxide, the PMI showed a significant association with the overall survival (OS) and disease-free survival (DFS) in SCC patients (hazard ratios 0.50 and 0.56, 95% confidence intervals 0.39-0.65 and 0.45-0.71, respectively). On the other hand, in ADC patients, the PMI had no impact on the OS or DFS. CONCLUSIONS: The PMI was significantly associated with the survival of lung SCC patients, but not of lung ADC patients, suggesting the presence of a previously unidentified relationship between skeletal muscle and lung SCC progression.

Risk Factors for the Exacerbation of Myasthenic Symptoms After Surgical Therapy for Myasthenia Gravis and Thymoma.

Extended thymectomy is employed for patients with myasthenia gravis (MG) and/or thymoma with elevated serum antiacetylcholine receptor antibody (AchR) titers. However, MG symptoms occasionally worsen in post-thymectomy patients. We explored the risk factors for exacerbation of MG symptoms after surgical therapy for patients with MG and/or thymoma with an elevated AchR titer. We retrospectively analyzed 90 patients suffering from MG and/or thymoma with an elevated AchR titer who underwent thymectomy in our institute. Patients were classified into Improved, Unchanged, and Exacerbated groups by assessing their postoperative myasthenic symptoms, amount of medication, and incidence of myasthenic crisis. Risk factors for postoperative exacerbation of myasthenic symptoms were assessed by comparing the Exacerbated with the Improved and Unchanged groups. Of the 90 patients, 29 were classified into the Improved group, 47 into the Unchanged group, and 14 into the Exacerbated group. The presence of thymoma and Masaoka stage were significantly different between the Exacerbated and Improved/Unchanged groups. Although preoperative AchR titers did not significantly differ among the groups, the perioperative AchR titers in the Exacerbated group were significantly higher than those in the other groups (P = 0.003). A multiple logistic regression analysis with stepwise forward selection showed that advanced-stage thymoma was a risk factor for postoperative exacerbation of myasthenic symptoms (P = 0.007). Patients with advanced-stage thymoma have a relative risk for exacerbation of myasthenic symptoms after surgical therapy.

Primary peritoneal carcinoma with late-phase pulmonary metastases: a case report.

BACKGROUND: Primary peritoneal carcinoma (PPC) is a very rare and aggressive type of malignancy with a poor prognosis. CASE PRESENTATION: A 66-year-old woman was referred to our hospital with two pulmonary nodules that developed after PPC resection and postoperative adjuvant chemotherapy administered 5 years earlier. Computed tomography revealed a 1.3-cm-sized nodule in the left lung with a small airspace in the posterior basal segment and a 0.9-cm-sized solid nodule in the apico-posterior segment that grew slightly within a 2-month period. 18F-Fluorodeoxyglucose-positron emission tomography of these lesions revealed respective maximum standardized uptake values of 7.11 and 2.46. Her serum cancer antigen-125 level remained within the normal range, despite elevation before the first surgery. The posterior basal segment and superior division were subjected to anatomical segmentectomy. An intraoperative frozen section examination could not distinguish metastatic PPC from primary lung cancer. Immunopathologically, the two nodules were identified as metastatic PPC. CONCLUSIONS: Our findings suggest that PPC patients may develop late-phase thoracic recurrence that is difficult to diagnose clinically after initial treatment in a potentially resectable setting.

Evaluation of intra-tumoral blood feeding to predict the effect of induction therapy in patients with locally advanced lung cancer.

There is little known about predictors of the effects of induction therapy in locally advanced lung cancer, including superior sulcus tumors. We analyzed whether intra-tumoral blood feeding could predict a pathologic complete response (pCR). Patients who underwent induction therapy followed by surgery for locally advanced lung cancer were retrospectively reviewed. The intra-tumoral blood feeding was defined by the CT value (HU, Hounsfield unit), which was calculated by subtracting the non-enhanced value from the contrast-enhanced value (divided into the early and delayed phase) at the maximum diameter of the tumor on dynamic CT. The cases were classified, according to the efficacy of induction therapy, into the pCR and residual tumor (pRT) group. There were 38 cases of T3 and 12 of T4; the induction therapy consisted of chemoradiotherapy in 39 patients, chemotherapy in 6, and radiotherapy in 5. A pCR was obtained in 15 (30%) patients. The mean CT values of the early and delayed phases in the pCR group were 14.8 and 30.7 HU, while those in the pRT were 15.3 and 32.2 HU, respectively. A logistic regression analysis revealed that a smaller tumor size (< 42 mm) was a non-significant predictor of a pCR (p = 0.09); the maximum standardized uptake value on FDG-PET and the CT values on the early and delayed phases of dynamic CT were not associated with the achievement of a pCR. In conclusion, intra-tumoral blood feeding of the locally advanced lung cancer did not predict the effects of induction therapy, whereas smaller sized tumors tended to show a better response.

The tumor doubling time is a useful parameter for predicting the histological type of thymic epithelial tumors.

PURPOSE: We assessed the utility of the tumor doubling time (TDT) for predicting the histological type of thymic epithelial tumors. METHODS: We retrospectively reviewed 130 patients with thymic epithelial tumors who underwent computed tomography two or more times before surgery. The patients were divided into low-risk thymoma (types A, AB and B1), high-risk thymoma (types B2 and B3) and thymic carcinoma (thymic carcinoma and thymic neuroendocrine tumor) groups. In the 96 patients who showed tumor enlargement, the relationship between the histological type and the TDT of the tumor was investigated. RESULTS: The study population included 55 men and 41 women from 26 to 82 years of age. The TDT of the thymic carcinoma group (median 205 days) was significantly shorter in comparison to the low-risk thymoma (median 607 days) and high-risk thymoma (median 459 days) groups. No significant differences were observed between the low-risk thymoma and high-risk thymoma groups. When we set the cutoff time for differentiating thymic carcinoma group from thymoma at 313 days, the sensitivity and specificity were 83.8% and 82.1%, respectively. CONCLUSIONS: The TDT is a useful parameter for differentiating between thymoma and thymic carcinoma group.

Verification of T descriptor with consolidation size for sub-centimeter non-small cell lung cancer.

PURPOSE: In the most recent (eighth) edition of the TNM classification, the clinical T descriptor has been adapted to measure the consolidation size of sub-solid lung cancer. Sub-centimeter non-small cell lung cancer (NSCLC) has thereby been subclassified into three groups: Tis, T1mi, and T1a; however, the revision has not been validated well. Thus, we investigated the clinicopathological characteristics and long-term oncological outcomes of sub-centimeter NSCLCs based on the solid size. METHODS: The subjects of this retrospective review were 99 patients who underwent complete resection for NSCLC with ≤ 1 cm in consolidation size on computed tomography (CT). Survival was reanalyzed after reclassification according to the new TNM classification. RESULTS: This cohort consisted of 14 patients with cTis tumors, 18 with cT1mi tumors, and 67 with cT1a tumors. Among the patients with tumors classified as cT1a, two had lymph node metastasis and two had vascular invasion. The cumulative incidences of recurrence at 5 and 10 years were 0% for cTis/cT1mi tumors, and 4.5% and 6.1% for cT1a tumors, respectively. CONCLUSIONS: There may be pathological and survival differences between cTis/cT1mi tumors and cT1a tumors, but not between cTis tumors and cT1mi tumors.

Multimodality therapy for thymoma patients with pleural dissemination.

BACKGROUND: Although multidisciplinary treatment is recommended for patients with advanced stage and recurrent thymoma, a detailed treatment strategy remains controversial. We have performed a multimodality therapy of induction chemotherapy (CAMP therapy: cisplatin, doxorubicin, and methylprednisolone) combined with surgery for those patients. We now conducted a retrospective study for investigating the results of this multimodality therapy for thymoma patients with pleural dissemination. PATIENTS AND METHODS: Between 2003 and 2017, 201 patients underwent surgical resection for thymomas. Twenty-six of them received induction CAMP therapy followed by surgery, and 19 of them with pleural dissemination were enrolled in this study. Those cohort were divided into 2 groups by employing surgical procedures: extrapleural pneumonectomy (EPP) group (n = 10) and resection of plural dissemination (RPD) group (n = 9). RESULTS: The median age of all patients was 49 years. Based on the WHO classification, the histological diagnoses of those thymomas were as follows: Type B1 (n = 1), Type B2 (n = 13), and Type B3 (n = 5). Seven patients were complicated with myasthenia gravis (MG). Clinical stage of the 13 primary cases based on the Masaoka classification were stage IV, and the remaining six cases had recurrent pleural dissemination after surgery. Partial response in induction CAMP therapy was obtained in 78.9% (n = 15) of the patients. Adverse events (Grade 4) occurred in 2 patients (10.5%). Postoperative complications (Grade 4) were observed in 2 patients (10.5%). In all of the enrolled patients, the five-year overall survival rate (5Y-OS) and 5-year progression-free survival rate (5Y-PFS) were 76.7% and 55.1%, respectively. In the EPP group, 5Y-OS and 5Y-PFS were 83.3% and 83.3%, respectively, and in the RPD group, 70.0% and 29.6%, respectively. CONCLUSIONS: Multidisciplinary treatment using induction CAMP therapy and surgical resection for thymoma patients with pleural dissemination was effective and feasible. Because of the low recurrent rate of disease, young patients with good cardiopulmonary function and well-controlled MG might be good candidates for EPP.

Verification of the diagnostic strategy for anterior mediastinal tumors.

BACKGROUND: For thymic epithelial tumors (TETs), the National Comprehensive Cancer Network guideline has suggested that complete excision of the tumor should be performed without a preoperative biopsy when resectable. However, little evidence has been provided to support this strategy. The purpose of this study was to review our diagnostic process and to evaluate the validity of radical resection of anterior mediastinal masses (AMMs) without pathological confirmation. METHODS: A total of 254 patients underwent surgical resection for AMMs between 2004 and 2015. This study included 181 patients with likely TETs according to clinical features, serum levels of tumor markers and autoimmune-antibodies, and radiological findings. In addition, AMMs likely TETs were classified into resectable or unresectable tumors. We retrospectively reviewed the diagnostic process of those patients and validated surgical resection of AMMs without a definitive diagnosis. RESULTS: Among 254 patients, 181 were suspected of having a TET based on the serum levels of tumor markers and autoimmune-antibodies and the radiological findings. Of them, 157 patients were deemed resectable and underwent surgical resection without histological confirmation, and 144 (92%) were diagnosed with TETs in the final pathological examinations. In 13 patients with non-TETs, the tumors were difficult to differentiate from TETs by imaging and clinical findings alone. CONCLUSIONS: A total of 92% of patients suspected of having a TET and who underwent complete resection without pathological confirmation were accurately diagnosed and properly treated. Surgical resection without a definitive diagnosis was feasible in patients suspected of having a TET when they were considered resectable.

Clinicopathologic Features of Thymoma With the Expression of Programmed Death Ligand 1.

BACKGROUND: Programmed death ligand 1 (PD-L1) is reportedly expressed in various malignancies and is considered a prognostic factor. We attempted to reveal the usefulness of the PD-L1 expression as a prognostic factor in patients with thymoma. METHODS: Eighty-one patients with thymoma who underwent surgical resection between 2004 and 2015 were retrospectively reviewed. The PD-L1 expression was evaluated by immunohistochemistry and stratified by the proportion of positive tumor cells. Strong membranous reactivity of the PD-L1 antibody in 1% or more of tumor cells was considered "positive." The association between the PD-L1 expression and the clinicopathologic features was investigated. RESULTS: The PD-L1 expression was positive in 22 patients (27%) and negative in 59 patients (73%). The PD-L1 positivity was significantly associated with type B2 and B3 thymoma (p < 0.001) and stage III and IV disease (p = 0.048). In addition, PD-L1 positive tumors showed a significantly higher maximum standardized uptake value than PD-L1 negative tumors (p = 0.026). The 5-year disease-free survival rate was 82% in PD-L1 positive patients and 88% in PD-L1 negative patients, showing no significant difference (p = 0.57). Furthermore, PD-L1 positivity was not an independent prognostic factor for the disease-free survival on a Cox proportional hazards analysis (p = 0.59). CONCLUSIONS: A strong expression of PD-L1 in thymoma was significantly associated with type B2 and B3 and higher pathologic stages. In addition, PD-L1 positivity was associated with an increased maximum standardized uptake value of the tumor. However, patients with PD-L1 positive thymomas did not show a significantly worse prognosis than patients with PD-L1 negative tumors.

A survival analysis using physique-adjusted tumor size of non-small cell lung cancer.

BACKGROUND: Differences in individual body sizes have not been well considered when analyzing the survival of patients with non-small cell lung cancer (NSCLC). We hypothesized that physique-adjusted tumor size is superior to actual tumor size in predicting the prognosis. METHODS: Eight hundred and forty-two patients who underwent R0 resection of NSCLC between 2005 and 2012 were retrospectively reviewed, and overall survival (OS) was evaluated. The physique-adjusted tumor size was defined as: x-adjusted tumor size = tumor size × mean value of x/individual value of x [x = height, weight, body surface area (BSA), or body mass index (BMI)]. Tumor size category was defined as ≤2, 2-3, 3-5, 5-7, and >7 cm. The separation index (SEP), which is the weighted mean of the absolute value of estimated regression coefficients over the subgroups with respect to a reference group, was used to measure the separation of subgroups. RESULTS: The mean values of height, weight, BSA, and BMI were 160.7 cm, 57.6 kg, 1.59 m2, and 22.2 kg/m2, respectively. The 5-year survival rates ranged from 88-59% in the non-adjusted tumor size model (SEP 1.937), from 90-57% in the height-adjusted model (SEP 2.236), from 91-52% in the weight-adjusted model (SEP 2.146), from 90-56% in the BSA-adjusted model (SEP 2.077), and from 91-51% in the BMI-adjusted model (SEP 2.169). CONCLUSIONS: The physique-adjusted tumor size can separate the survival better than the actual tumor size.

Predictors for hilar/intrapulmonary lymph node metastasis in discrete type of clinical N1 non-small cell lung cancer.

OBJECTIVE: Accurate preoperative evaluation of lymph nodes can provide optimal treatment for patients. However, in patients with clinical N1 disease (cN1) non-small cell lung cancer (NSCLC), no suitable predictor has been identified for hilar/intrapulmonary lymph node metastasis (pathological N1 disease; pN1). The purpose of this study was to identify pN1 in cN1 NSCLC patients. METHODS: We retrospectively reviewed the clinicoradiological features of 109 patients with a discrete type of cN1 NSCLC who had undergone complete resection at our institution from 2004 to 2015. The association between clinicoradiological variables and nodal status was analyzed to identify predictors for pN1. RESULTS: The cohort consisted of 77 males and 32 females, ranging in age from 39 to 84 years. The breakdown by pathological N category was 40 (37%) pN0, 41 (38%) pN1, and 28 (25%) pN2 patients. Maximum lymph node diameter was identified as a significant predictor for pN1, with an odds ratio of 1.25 (P = 0.010). When limited to 63 patients who underwent positron emission tomography (FDG-PET) at our institution, the maximum standardized uptake value (SUVmax) of the lymph node was an independent predictor, with an odds ratio of 1.91 with logistic regression analysis (P = 0.004). The size of lymph node and the SUVmax were significant factors for pN1, with optimal cut-off values of 13 mm and 4.28, respectively. CONCLUSIONS: Among the patients with cN1, maximum lymph node size and SUVmax of the FDG-PET were significant predictors for pN1.