A comparison between 2- and 3-dimensional approaches to solid component measurement as radiological criteria for sublobar resection in lung adenocarcinoma ≤ 2 cm in size.

PURPOSE: We compared three-dimensional (3D) and two-dimensional (2D) measurements of the solid component to determine radiological criteria for sublobar resection of lung adenocarcinoma ≤ 2 cm in size. METHODS: We included 233 surgical cases. The maximum size of the solid component for 3D measurement was calculated by delineating the solid component on successive axial images and reconstructing the 3D surface model. RESULTS: The predictive performance for adenocarcinoma in situ (n = 43) and minimally invasive adenocarcinoma (n = 77) were equivalent to areas under the curve of 0.871 and 0.857 for 2D and 3D measurements (p = 0.229), respectively. A solid component of 5 mm had a prognostic impact on both measurements ( ≤ 5 mm versus > 5 mm; p = 0.003 for 2D and p = 0.002 for 3D, log-rank test). Survival rates at 5 years were 94.7-96.9% following lobectomy and sublobar resection among patients with a solid component ≤ 5 mm in size. Sublobar resection resulted in worse survival rates, with declines at 5 years of 15.8% on 2D and 11.5% on 3D measurements, than lobectomy in patients with a solid component > 5 mm in size. CONCLUSIONS: A solid component ≤ 5 mm in size is an appropriate criterion for sublobar resection for both measurements. In addition, 2D measurement is justified because of its simple implementation.

Prognostic significance of the preoperative neutrophil-to-lymphocyte ratio for complete resection of thymoma.

PURPOSE: The preoperative peripheral neutrophil-to-lymphocyte ratio (NLR) is associated with a poor prognosis for various cancers. We evaluated the prognostic role of the preoperative NLR in patients with thymoma. METHODS: We reviewed the medical records of 254 patients who underwent resection of thymic epithelial tumors at our institution. Patients were excluded if they had received steroid therapy, neoadjuvant therapy, or incomplete resection, or if they had thymic carcinoma or Good's syndrome, recurrence of thymoma, or missing data. The NLR was measured preoperatively, and outcomes of patients with a low (< 1.96) vs those with a high (≥ 1.96) NLR were compared statistically. RESULTS: Of 159 eligible patients, 59 (37.1%) had a high NLR and 100 (62.9%) had a low NLR. Overall survival (OS), recurrence-free survival (RFS), disease-specific survival (DSS), disease-related survival (DRS), and the cumulative incidence of recurrence (CIR) differed significantly between the groups. Multivariate analyses revealed that a high NLR was independently associated with disease-related survival and a cumulative incidence of recurrence. A high NLR was also associated with a higher risk of recurrence of Masaoka stage I or II thymoma. CONCLUSIONS: An elevated preoperative NLR was associated with poor outcomes after thymoma resection. Thus, the NLR may be a useful biomarker of the postoperative prognosis of thymoma.

Prediction and prioritization of neoantigens: integration of RNA sequencing data with whole-exome sequencing.

The importance of neoantigens for cancer immunity is now well-acknowledged. However, there are diverse strategies for predicting and prioritizing candidate neoantigens, and thus reported neoantigen loads vary a great deal. To clarify this issue, we compared the numbers of neoantigen candidates predicted by four currently utilized strategies. Whole-exome sequencing and RNA sequencing (RNA-Seq) of four non-small-cell lung cancer patients was carried out. We identified 361 somatic missense mutations from which 224 candidate neoantigens were predicted using MHC class I binding affinity prediction software (strategy I). Of these, 207 exceeded the set threshold of gene expression (fragments per kilobase of transcript per million fragments mapped ≥1), resulting in 124 candidate neoantigens (strategy II). To verify mutant mRNA expression, sequencing of amplicons from tumor cDNA including each mutation was undertaken; 204 of the 207 mutations were successfully sequenced, yielding 121 mutant mRNA sequences, resulting in 75 candidate neoantigens (strategy III). Sequence information was extracted from RNA-Seq to confirm the presence of mutated mRNA. Variant allele frequencies ≥0.04 in RNA-Seq were found for 117 of the 207 mutations and regarded as expressed in the tumor, and finally, 72 candidate neoantigens were predicted (strategy IV). Without additional amplicon sequencing of cDNA, strategy IV was comparable to strategy III. We therefore propose strategy IV as a practical and appropriate strategy to predict candidate neoantigens fully utilizing currently available information. It is of note that different neoantigen loads were deduced from the same tumors depending on the strategies applied.

Tumoral CD10 expression correlates with aggressive histology and prognosis in patients with malignant pleural mesothelioma.

BACKGROUND: Currently, tumor-node-metastasis stage and histologic type are the established prognostic factors for malignant pleural mesothelioma, whereas no prognostic markers have been established for clinical practice. We investigated the prognostic value of CD10, a metalloproteinase that can promote cancer aggressiveness through enzymatic degradation and intracellular signaling crosstalk, in malignant pleural mesothelioma. METHODS: CD10 immunostaining was performed for 176 cases of malignant pleural mesothelioma (epithelioid, 148; biphasic, 14; sarcomatoid, 14), and its expression was dichotomized as negative (no staining) or positive (any staining). Epithelioid tumors were classified as pleomorphic subtype when cytologic pleomorphism was ≥10 % of the tumor. Overall survival (OS) was analyzed by log-rank tests and Cox proportional hazard models. RESULTS: Tumoral CD10 expression was identified in 42 % of epithelioid non-pleomorphic tumors, 57 % of epithelioid pleomorphic tumors, 79 % of biphasic tumors, and 93 % of sarcomatoid tumors (p < 0.001). Positive CD10 expression was correlated with higher mitotic count (p = 0.002). Overall survival for patients with positive CD10 expression was significantly shorter than that for patients with negative CD10 expression in all patients (p = 0.001) and in patients with epithelioid tumor (p = 0.04). On multivariate analysis, CD10 expression was an independent prognostic factor for all patients (hazard ratio 1.48; p = 0.019). CONCLUSIONS: Tumoral CD10 expression correlated with aggressive histologic types and higher mitotic activity and is an independent prognostic factor for patients with malignant pleural mesothelioma.

Using frozen section to identify histological patterns in stage I lung adenocarcinoma of ≤ 3 cm: accuracy and interobserver agreement.

AIMS: The IASLC/ATS/ERS classification of lung adenocarcinoma provides a prognostically significant histological subclassification. The aim of this study was to investigate the accuracy, limitations and interobserver agreement of frozen sections for predicting histological subtype. METHODS AND RESULTS: Frozen section and permanent section slides from 361 resected stage I lung adenocarcinomas ≤ 3 cm in size were reviewed for predominant histological subtype and the presence or absence of lepidic, acinar, papillary, micropapillary and solid patterns. Fifty cases were additionally reviewed by three pathologists to determine interobserver agreement. To test the accuracy of frozen section in judging degree of invasion, five pathologists reviewed frozen section slides from 35 cases with a predominantly lepidic pattern. There was moderate agreement on predominant histological subtype between frozen sections and final diagnosis (κ = 0.565). Frozen sections had high specificity for micropapillary and solid patterns (94% and 96%, respectively), but sensitivity was low (37% and 69%, respectively). The interobserver agreement was satisfactory (κ > 0.6, except for the acinar pattern). CONCLUSIONS: Frozen section can provide information on the presence of aggressive histological patterns-micropapillary and solid-with high specificity but low sensitivity. It was difficult to predict the predominant pattern on the basis of frozen sections, mostly because of sampling issues.

[Tracheal Resection and Reconstruction for a Squamous Cell Carcinoma of the Trachea;Report of a Case].

We report a case of tracheal resection and reconstruction for a squamous cell carcinoma of the trachea that was found in an 82-year-old male patient who had underwent right lower lobectomy for an adenosquamous cell carcinoma 3.5 years before. He noticed bloody sputum. Chest computed tomography (CT) revealed a 15 mm tumor in the anterior wall of the trachea. A transbronchial biopsy for the tracheal tumor showed a squamous cell carcinoma. Under right thoracotomy, we resected the tumor with 3 tracheal rings. Histologically a squamous cell carcinoma was diagnozed. As there was intraepithelial spread of cancer cells in the oral margin, the tracheal tumor was suspected to be a primary tracheal tumor rather than a metastasis from lung cancer. After the surgery, combination therapies of an external radiation therapy for 50 Gy and brachytherapy 2 times for totally 8 Gy were performed as a postoperative adjuvant therapy. He does not have any signs of recurrence in 1 year and 6 months after the surgery.

Thyroid transcription factor-1 expression is an independent predictor of recurrence and correlates with the IASLC/ATS/ERS histologic classification in patients with stage I lung adenocarcinoma.

BACKGROUND: In the current study, the authors investigated whether thyroid transcription factor-1 (TTF-1) expression is correlated with the International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification and whether it stratifies patients with stage I lung adenocarcinoma with respect to disease recurrence. METHODS: Patients with stage I lung adenocarcinoma were classified according to the IASLC/ATS/ERS classification. Tissue microarrays were constructed and immunostaining for TTF-1 was performed. A total of 452 cases were available for analysis. Tumors were dichotomized based on the intensity of nuclear TTF-1 expression as negative (score of 0) or positive (score of 1-3). The cumulative incidence of recurrence (CIR) was used to estimate disease recurrence probabilities. RESULTS: TTF-1 expression was identified in 92% of patients, including 100% of patients with minimally invasive or lepidic-predominant adenocarcinoma, 94% of patients with acinar-predominant adenocarcinoma, 98% of patients with papillary-predominant adenocarcinoma, 93% of patients with micropapillary-predominant adenocarcinoma, 86% of patients with solid-predominant adenocarcinoma, 67% of patients with colloid-predominant adenocarcinoma, and 47% of patients with invasive mucinous carcinoma. The CIR for patients with negative TTF-1 expression (n = 34 patients; 5-year CIR, 40%) was significantly higher than that for patients with positive TTF-1 expression (n = 418 patients; 5-year CIR, 15%) (P < .001). Among the patients with intermediate-grade tumors, the CIR for patients with negative TTF-1 expression (n = 16 patients; 5-year CIR, 45%) was significantly higher than that for patients with positive TTF-1 expression (n = 313 patients; 5-year CIR, 14%) (P < .001). On multivariate analysis, negative TTF-1 expression was found to be significantly correlated with an increased risk of disease recurrence (hazards ratio, 2.55; P = .009). CONCLUSIONS: TTF-1 expression was found to be an independent predictor of disease recurrence, stratifying intermediate-grade tumors into 2 prognostic subsets, and it correlates with the IASLC/ATS/ERS classification.

Preoperative consolidation-to-tumor ratio and SUVmax stratify the risk of recurrence in patients undergoing limited resection for lung adenocarcinoma ≤2 cm.

PURPOSE: Limited resection is an increasingly utilized option for treatment of clinical stage IA lung adenocarcinoma (ADC) ≤2 cm (T1aN0M0), yet there are no validated predictive factors for postoperative recurrence. We investigated the prognostic value of preoperative consolidation/tumor (C/T) ratio [on computed tomography (CT) scan] and maximum standardized uptake value (SUVmax) on (18)F-fluorodeoxyglucose-positron emission tomography (PET) scan. METHODS: We retrospectively reviewed 962 consecutive patients who underwent limited resection for lung cancer at Memorial Sloan-Kettering between 2000 and 2008. Patients with available CT and PET scans were included in the analysis. C/T ratio of 25 % (in accordance with the Japan Clinical Oncology Group 0201) and SUVmax of 2.2 (cohort median) were used as cutoffs. Cumulative incidence of recurrence (CIR) was assessed. RESULTS: A total of 181 patients met the study inclusion criteria. Patients with a low C/T ratio (n = 15) had a significantly lower 5-year recurrence rate compared with patients with a high C/T ratio (n = 166) (5-year CIR, 0 vs. 33 %; p = 0.015), as did patients with low SUVmax (n = 86) compared with patients with high SUVmax (n = 95; 5-year CIR, 18 vs. 40 %; p = 0.002). Furthermore, within the high C/T ratio group, SUVmax further stratified risk of recurrence [5-year CIR, 22 % (low) vs. 40 % (high); p = 0.018]. CONCLUSIONS: With the expected increase in diagnoses of small lung ADC as a result of more widespread use of CT screening, C/T ratio and SUVmax are widely available markers that can be used to stratify the risk of recurrence among cT1aN0M0 patients after limited resection.

Low truncal muscle area on chest computed tomography: a poor prognostic factor for the cure of early-stage non-small-cell lung cancer†.

OBJECTIVES: Depletion in skeletal muscle is closely associated with limited physical ability and high mortality. In this study, we evaluated the prognostic significance of skeletal muscle depletion in patients with early-stage non-small-cell lung cancer. METHODS: A retrospective analysis of patients with pathological stages I-II lung cancer, who underwent curative resection between 2009 and 2013, was conducted. The truncal muscle index (TMI) (area/height2) at the first lumbar vertebral level was measured by preoperative axial computed tomography. Overall survival and recurrence-free survival were compared between the lowest gender-specific quartile of the TMI and the other quartiles. RESULTS: A total of 314 subjects were included in the study. The cumulative 5-year recurrence-free and overall survival rates were significantly shorter in patients with lower TMIs (69% vs 83.5%, P = 0.028; 64.8% vs 80.1%, P = 0.003, respectively). In multivariable models, the TMI was identified as an independent prognostic factor for overall survival (P = 0.017, hazard ratio 1.84, 95% confidence interval 1.12-3.05), after adjusting for age, gender, preoperative serum albumin, carcinoembryonic antigen, neutrophil to lymphocyte ratio and pathological stage. CONCLUSIONS: A low preoperative TMI was associated with a poor postoperative outcome in patients with early-stage non-small-cell lung cancer. This factor may be included in the preoperative assessment of patients, for whom surgical intervention is considered.

Spread through air spaces is an independent predictor of recurrence in stage III (N2) lung adenocarcinoma.

OBJECTIVES: Spread through air space (STAS) is recognized as a pattern of invasion in lung adenocarcinoma and has been reported to be a predictor of recurrence and survival in patients with early-stage lung adenocarcinoma. However, this parameter has not been studied well in stage III (N2) lung adenocarcinoma. In this study, we evaluated the association between STAS invasion patterns and recurrence and survival in stage III (N2) lung adenocarcinoma. METHODS: We retrospectively reviewed data from 76 patients at University of Tokyo with stage III (N2) lung adenocarcinoma who underwent surgery from August 1998 to December 2013. Statistical analysis was performed to determine the impact of STAS invasion clinicopathological features and clarify the relationship between this pattern of invasion and survival. RESULTS: Tumour STAS was observed in 46 of 76 patients (60.5%) and was significantly associated with the presence of lymphatic invasion (P < 0.001), papillary components (P < 0.001) and micropapillary components (P < 0.001). STAS was also significantly associated with recurrence (5-year recurrence-free probability: 19.0% vs 46.1%, P < 0.05). Univariate analyses showed that STAS was a significant risk factor for recurrence (hazard ratio 1.94, 95% confidence interval 1.07-3.51; P = 0.029). CONCLUSIONS: The presence of STAS invasion pattern is a significant risk factor for recurrence in stage III (N2) lung adenocarcinoma.

Procedure-Specific Risk Prediction for Recurrence in Patients Undergoing Lobectomy or Sublobar Resection for Small (≤2 cm) Lung Adenocarcinoma: An International Cohort Analysis.

INTRODUCTION: This work was performed to develop and validate procedure-specific risk prediction for recurrence following resection for early-stage lung adenocarcinoma (ADC) and investigate risk prediction utility in identifying patients who may benefit from adjuvant chemotherapy (ACT). METHODS: In patients who underwent resection for small (≤2 cm) lung ADC (lobectomy, 557; sublobar resection, 352), an association between clinicopathologic variables and risk of recurrence was assessed by a competing risks approach. Procedure-specific risk prediction was developed based on multivariable regression for recurrence. External validation was conducted using cohorts (N = 708) from Japan, Taiwan, and Germany. The accuracy of risk prediction was measured using a concordance index. We applied the lobectomy risk prediction approach to a propensity score-matched cohort of patients with stage II-III disease (n = 316, after matching) with or without ACT and compared lung cancer-specific survival between groups among low- or high-risk scores. RESULTS: Micropapillary pattern, solid pattern, lymphovascular invasion, and necrosis were involved in the risk prediction following lobectomy, and micropapillary pattern, spread through air spaces, lymphovascular invasion, and necrosis following sublobar resection. Both internal and external validation showed good discrimination (concordance index in lobectomy and sublobar resection: internal, 0.77 and 0.75, respectively; and external, 0.73 and 0.79, respectively). In the stage II-III propensity score-matched cohort, among high-risk patients, ACT significantly reduced the risk of lung cancer-specific death (subhazard ratio 0.43, p = 0.001), but not among low-risk patients. CONCLUSIONS: Procedure-specific risk prediction for patients with resected small lung ADC can be used to better prognosticate and stratify patients for further interventions.

Impact of the 8th Edition of the UICC-TNM Classification on Clinical Stage 0-IA Lung Adenocarcinoma: Does the New Classification Predict Postoperative Prognosis More Precisely than the Previous One?

PURPOSE: Early lung adenocarcinoma has been more frequently found recently. The 8th edition of the Union for International Cancer Control (UICC)-Tumor Node Metastasis (TNM) classification for lung cancer has been effective since January 2017. This study aims to elucidate advantages of the current classification for patients with clinical stage 0-IA lung adenocarcinoma, in comparison with the older one. METHODS: We retrospectively reviewed the data of clinical stage IA (7th edition) lung adenocarcinoma patients who underwent surgery at our institute from 2001 to 2012, and reclassified them by the 8th edition. Survival analysis was used to evaluate the impact of the two classifications. RESULTS: In all, 281 cases were eligible. Clinical T-factors (8th) were significant prognostic factors for overall survival (P = 0.001), recurrence-free survival (P <0.001), and cancer-specific survival (P = 0.001). However, those in the previous edition were not (P = 0.894, P = 0.144, and P = 0.822, respectively). CONCLUSION: The 8th edition of the UICC-TNM classification predicts postoperative prognosis more precisely than the 7th one in clinical stage 0-IA lung adenocarcinoma. It is probably because the stage distribution of the population, which included in the research project the 8th edition based on, has been changed, and the new edition develops more accurate staging criteria for ground-glass nodule (GGN).

An Unusual Invasive Ectopic Thymoma in the Thyroid and Anterior Mediastinum.

An 81-year-old woman with a 2-year history of dysphagia detected a cervical mass. Computed tomography showed a thyroid tumor extending through the superior and anterior mediastinum. Analysis of an incisional biopsy specimen revealed a thymoma. Total resection of the thyroid and mediastinal tumor was performed. The thymoma invaded the anterior tracheal wall and left brachiocephalic vein. Pathologic examination revealed thymoma type B1 concomitant with B2 and B3 (World Health Organization classification), Masaoka IVb, and T3 N2 M0-IVb, with cervical lymph node metastasis. Clinicians must be cautious during radical operations for invasive ectopic thymomas.

High CCR4 expression in the tumor microenvironment is a poor prognostic indicator in lung adenocarcinoma.

BACKGROUND: Clinical trials of anti-CCR4 antibody for solid cancers with or without other immune-modulating agents including immune checkpoint blockade therapy are currently underway. However, little is known about the roles of CCR4+ lymphocytes and their prognostic impact in lung cancer. We hypothesized that high CCR4 expression in the tumor microenvironment would be associated with a poor prognosis and would act as a biomarker in lung adenocarcinoma. METHODS: First, the prognostic impact of CCR4 gene expression was explored using pooled data from public transcriptomic databases with online survival analysis software. Second, tissue microarrays (TMAs) were constructed from resected lung adenocarcinoma specimens from tumors up to 3 cm in size. The density of CCR4+ lymphocytes infiltrating the tumor was then assessed by immunohistochemistry and related to survival. Confounding factors were controlled for by multivariate analysis using the Cox proportional hazards model. RESULTS: Higher than median expression of the CCR4 gene was identified as an independent poor prognostic factor for overall survival (OS) by multivariate analysis of 720 lung adenocarcinoma patients in the public databases [HR =1.55 (95% CI: 1.03-2.35), P=0.037]. Consistent with this, high CCR4+ tumor-infiltrating lymphocyte (TIL) density was found to be an independent poor prognostic factor for both OS [HR =2.24 (1.01-5.34), P=0.049] and recurrence-free survival (RFS) [HR =2.20 (1.16-4.39), P=0.017] in the patients from whom TMA were obtained (n=180). Age, male gender, predominantly non-lepidic histological subtype, nodal involvement, and low CD8+ TIL density were also independent poor prognostic factors. However, FOXP3 gene expression and Foxp3+ lymphocyte infiltration did not possess any prognostic value in either study. CONCLUSIONS: High CCR4 expression in the tumor microenvironment may be a poor prognostic factor in lung adenocarcinoma. Patients with high CCR4+ lymphocyte infiltration may have a poor prognosis and thus be suitable candidates for clinical trials of anti-CCR4 antibody treatment.

Breast cancer in first-degree relatives and risk of lung cancer: assessment of the existence of gene sex interactions.

BACKGROUND: Previous studies have shown the sex differences in lung cancer and the associations between estrogen-related genes and non-small cell lung cancer. In the present study, we assumed the existence of shared candidate genes that are common in lung and breast cancers, and examined whether women with a family history of breast cancer are at increased risk of lung cancer compared with men, especially adenocarcinoma, in a case-only study. METHODS: This case-only study was conducted based on the Lung Cancer Database Project at the National Cancer Center Hospital East. A total of 1566 patients with newly diagnosed primary lung cancer were consecutively recruited between 1999 and 2003. Information on their family history of cancer and smoking habit was obtained from a self-administered questionnaire. To assess an interactions between two factors, odds ratios for interaction (ORis) and 95% confidence intervals (CIs) were calculated by case-only contingency table. RESULTS: A statistically significant ORi was observed between a family history of breast cancer in first-degree relatives (parent and siblings, not including children) and the sex of a patient (ORi: 2.22, 95% CI: 1.02-4.81). A stratified analysis by histologic subtypes showed a statistically significant ORi only for adenocarcinoma (ORi: 3.27, 95% CI: 1.19-8.98). No other family history of cancer, such as stomach, colon and lung cancer, showed a statistically significant ORi. CONCLUSION: This study suggests the possibility of gene-sex interaction in lung cancer.

Bilateral segmentectomies using virtual-assisted lung mapping (VAL-MAP) for metastatic lung tumors.

BACKGROUND: Virtual-assisted lung mapping (VAL-MAP) has been used not only in wedge resection but also in segmentectomy for hardly palpable lung nodules. We herein report a case of bilateral segmentectomy using VAL-MAP with chronological change of pulmonary function test results. CASE PRESENTATION: A 50-year-old female was found to have a colorectal cancer with pulmonary nodules in both sides of the lungs considered as synchronous lung metastases. After sigmoidectomy for primary cancer and chemotherapy, treatments for small nodules in both sides of the lungs were planned. Most nodules were small and supposed to be impalpable. We performed thoracoscopic segmentectomy of right S8 with the aid of VAL-MAP and, after 2 months, combined subsegmentectomy of left S8a and 9a and wide wedge resection of left S8b with the aid of VAL-MAP. All nodules suspected of lung metastases were successfully resected with adequate margins, and the decrease in pulmonary function was minimal compared with predicted postoperative forced vital capacity (FVC) and forced expiratory volume (FEV) 1.0 calculated by the numbers of subsegments. CONCLUSIONS: Bilateral segmentectomies of small impalpable metastatic tumors were performed successfully with the aid of VAL-MAP.

Role of post-mapping computed tomography in virtual-assisted lung mapping.

Background Virtual-assisted lung mapping is a novel bronchoscopic preoperative lung marking technique in which virtual bronchoscopy is used to predict the locations of multiple dye markings. Post-mapping computed tomography is performed to confirm the locations of the actual markings. This study aimed to examine the accuracy of marking locations predicted by virtual bronchoscopy and elucidate the role of post-mapping computed tomography. Methods Automated and manual virtual bronchoscopy was used to predict marking locations. After bronchoscopic dye marking under local anesthesia, computed tomography was performed to confirm the actual marking locations before surgery. Discrepancies between marking locations predicted by the different methods and the actual markings were examined on computed tomography images. Forty-three markings in 11 patients were analyzed. Results The average difference between the predicted and actual marking locations was 30 mm. There was no significant difference between the latest version of the automated virtual bronchoscopy system (30.7 ± 17.2 mm) and manual virtual bronchoscopy (29.8 ± 19.1 mm). The difference was significantly greater in the upper vs. lower lobes (37.1 ± 20.1 vs. 23.0 ± 6.8 mm, for automated virtual bronchoscopy; p < 0.01). Despite this discrepancy, all targeted lesions were successfully resected using 3-dimensional image guidance based on post-mapping computed tomography reflecting the actual marking locations. Conclusions Markings predicted by virtual bronchoscopy were dislocated from the actual markings by an average of 3 cm. However, surgery was accurately performed using post-mapping computed tomography guidance, demonstrating the indispensable role of post-mapping computed tomography in virtual-assisted lung mapping.

Micropapillary histological subtype in lung adenocarcinoma of 2 cm or less: impact on recurrence and clinical predictors.

OBJECTIVE: This study examined the clinical and radiological characteristics of adenocarcinoma having the micropapillary histological subtype. METHODS: We included 233 patients who were operated from 2001 to 2012 for lung adenocarcinoma of 2 cm or less. The pathology was reviewed according to the 2015 WHO classification. We defined adenocarcinoma with a micropapillary component as adenocarcinoma in which the area of the micropapillary histological subtype exceeded 5% of the tumor. The difference in cumulative incidence of recurrence (CIR) in the presence of death as a competing risk between two groups was assessed using the methods of Gray. RESULTS: Twenty-one cases (9.0%) had a micropapillary component. The micropapillary component was associated with a higher frequency of lymphatic invasion (28.6 vs. 7.5% in adenocarcinoma without a micropapillary component; P = 0.008) and vascular invasion (38.1 vs. 15.1%, P = 0.014) and lymph node metastasis (31.3 vs. 5.2%, P = 0.003). The median follow-up period was 6.5 years. CIR at 5 years was 23.8% [95% confidence interval (CI), 8.3-43.7%] for adenocarcinoma with a micropapillary component, and 11.4% (95% CI, 7.4-16.2%) for adenocarcinoma without a micropapillary component (P = 0.033). Adenocarcinoma with a micropapillary component was more frequent in solid nodules (17.8%, 16/90) on high-resolution computed tomography (HRCT) than in either ground-glass nodules (1.5%, 1/67) or part-solid nodules (5.3%, 4/76) (P = 0.001). The HRCT finding was the only preoperative factor that was associated with a micropapillary component in the multivariate analysis. CONCLUSIONS: The micropapillary component in adenocarcinoma should be regarded as indicative of a high-grade malignancy and was associated with the HRCT finding.

Squamous cell carcinoma of the lung showing a ground glass nodule on high-resolution computed tomography associated with pneumoconiosis: a case report.

BACKGROUND: Adenocarcinoma with lepidic growth pattern presents as a ground glass nodule (GGN) on high resolution computed tomography (CT), whereas peripheral pulmonary squamous cell carcinoma (SCC) usually presents as a solid nodule. We herein report a rare case of pulmonary SCC extending along the alveolar lumen representing as a GGN on a CT scan in a patient with pneumoconiosis. CASE PRESENTATION: A 77-year-old man with pneumoconiosis was found to have a gradually enlarging GGN in the right lower lobe of the lung on CT. An adenocarcinoma of the lung was suspected. The GGN was successfully resected by thoracoscopic segmentectomy. Pathological examination of the resected specimen was pathologically diagnosed as a stage IA SCC extending along the alveolar lumen. The patient had no evidence of recurrence 19 months after surgery. CONCLUSIONS: SCC should be included in the differential diagnosis of peripherally located GGNs, especially in patients at high risk of SCC of the lung such as those with pneumoconiosis.