Pathological Stage IA Lung Adenocarcinoma Research Articles

EP.07G.01 Computed Tomography Features of Pathological Stage IA Lung Adenocarcinoma Showing Spread Through Air Spaces.

EP.07G.01 Computed Tomography Features of Pathological Stage IA Lung Adenocarcinoma Showing Spread Through Air Spaces.

Sublobar resection for lung adenocarcinoma less than 2 cm containing solid or micropapillary components radiologically presented as consolidation-to-tumor ratio (CTR) ≤0.25 [ground-glass opacity (GGO)

The suitability of sublobar resection as a surgical approach for early-stage non-small cell lung cancer (NSCLC) remains unclear. This study investigated the feasibility of sublobar resection in patients with pathological-stage IA adenocarcinoma less than 2 cm characterized by a high-risk pathological subtype but exhibiting radiologically noninvasive features. We conducted a retrospective review of patients diagnosed with pathological stage IA lung adenocarcinoma who underwent surgical intervention between 2013 and 2017. The inclusion criteria included a maximum tumor diameter of 2.0 cm or less, a consolidation-to-tumor ratio (CTR) of 0.25 or less, and a histopathological confirmation of a solid or micropapillary component. Patients were categorized into sublobar resection and lobectomy groups, and propensity score matching was employed to mitigate potential confounders. The primary endpoints were lung cancer-specific survival (LCSS) and overall survival (OS). The study comprised 149 patients, with 84 in the lobectomy group and 65 in the limited resection group. In the overall cohort, the 5-year LCSS was 100% for both groups, while the 5-year OS was 97.6% (95% CI: 94.41-100.00%) in the lobectomy group and 100% in the sublobar resection group (P=0.21). After propensity score matching, the LCSS remained at 100% for both groups, and the 5-year OS was 97.14% in the lobectomy group and 100% in the sublobar resection group (P=0.32). Based on our experience, for lung adenocarcinoma containing solid/micropapillary subtype, a size less than 2 cm, and a CTR ≤0.25, the oncological outcomes appeared to be comparable between sublobar resection and lobectomy, suggesting that sublobar resection might serve as an equivalent alternative to lobectomy for such lesions.

Prognostic impact of noninvasive areas in resected pathological stage IA lung adenocarcinoma.

In non-small-cell lung cancer, ground-glass opacity on computed tomography imaging reflects pathological noninvasiveness and is a favorable prognostic factor. However, the significance of pathological noninvasive areas (NIAs) has not been fully revealed. In this study, we aimed to elucidate the prognostic impact of NIAs on lung adenocarcinoma. We analyzed 402 patients with pathological stage (p-Stage) IA lung adenocarcinoma who underwent surgery in 2013-2016 at two institutions and examined the association of the presence of NIAs with clinicopathological factors and prognosis. Furthermore, after using propensity-score matching to adjust for clinicopathological factors, such as age, sex, smoking history, pathological invasive area size, pathological T factor (p-T), p-Stage, and histological subtype (lepidic predominant adenocarcinoma [LPA] or non-LPA), the prognostic impact of NIAs was evaluated. Patients were divided into NIA-present (N = 231) and NIA-absent (N = 171) groups. Multivariable analysis showed that NIA-present was strongly associated with earlier p-T, earlier p-Stage, LPA, and epidermal growth factor receptor mutation. Kaplan-Meier survival analysis showed that the NIA-present group displayed a better prognosis than the NIA-absent group in disease-free survival (DFS) and overall survival (OS) (5-year DFS 94.6% vs. 87.2%, 5-year OS 97.2% vs. 91.1%). However, after adjusting for clinicopathological factors by propensity score matching, no significant differences in prognosis were identified between the NIA-present and NIA-absent groups (5-year DFS 92.4% vs 89.6%, 5-year OS 95.6% vs 94.3%). Our current study suggests that the prognostic impact of the presence of NIAs on lung adenocarcinoma is due to differences in clinicopathological factors.

Does the presence of a micropapillary component predict worse prognosis in pathological stage IA lung adenocarcinoma?

Considerable evidence has verified that the micropapillary pattern is significantly associated with worse prognosis in pulmonary adenocarcinoma. However, whether the presence of a micropapillary component in pathological stage IA lung adenocarcinoma is also related to worse prognosis remains unclear up to now. The aim of this meta-analysis was to identify the prognostic role of presence of a micropapillary component in pathological stage IA lung adenocarcinoma patients. Relevant studies were searched from the PubMed, EMBASE, Web of Science and CNKI databases and reviewed. The primary and secondary outcomes were the recurrence risk and long-term survival including the overall survival (OS) and disease-free survival (DFS), respectively. All statistical analysis were conducted by STATA 12.0 software. A total of 5257 lung adenocarcinoma patients at the pathological stage IA from ten retrospective studies were enrolled. The recurrence rates in pathological stage IA lung adenocarcinoma patients with and without the a micropapillary component were 32% [95% confidence interval (CI): 20%-44%] and 7% (95% CI: 4%-10%) separately and pooled results indicated that presence of a micropapillary component was an obvious risk factor for recurrence [odds ratio (OR)=3.41, 95% CI: 2.80-4.16, P＜0.001]. Besides, the presence of a micropapillary component was significantly related to poorer OS [hazard ratio (HR)=2.44, 95% CI: 1.28-4.68, P=0.007] and DFS (HR=2.60, 95% CI: 1.63-4.16, P＜0.001). Subgroup analysis focusing on invasive adenocarcinoma manifested consistent results. In pathological stage IA lung adenocarcinoma, the presence of a micropapillary component predicts obviously higher recurrence risk and worse prognosis even after focusing on invasive adenocarcinoma. However, more prospective high-quality studies are still needed to verify our findings.

Development and validation of a CT-based nomogram to predict spread through air space (STAS) in peripheral stage IA lung adenocarcinoma.

To develop and validate a simple-to-use nomogram based on preoperative CT to predict spread through air space (STAS) status of stage IA lung adenocarcinoma (ADC). In this retrospective study, 434 patients with pathological proven periphery stage IA lung adenocarcinoma were included, which consisted of 349 patients from center I for training group and 85 patients from Center II for test group. STAS was identified in 53 patients (40 patient in the training group and 13 patients in the test group). On the basis of preoperative CT images, 19 morphological characteristics were analyzed. Univariable analysis was used to explore the association between clinical and CT characteristics and STAS status in the training group (P < 0.002). Independent risk factors for STAS were identified using multivariable logistic regression analysis and then used to build a nomogram for preoperative predicting STAS status. Type of nodules, diameter of solid component, lobulation and percentage of the solid component (PSC) were associated with STAS status of peripheral stage IA lung ADCs statistical significantly. Multivariate logistics regression analysis revealed that PSC and lobulation were independent risk factors for STAS. The nomogram based on these factors achieved good predictive performance for STAS with a C-index of 0.803 in the training group and a well-fitted calibration curve. Using a cut-off value which was obtained from Youden index of the receiver operating characteristic (ROC) curve, a diagnosis accuracy of 70.6% was obtained in the test group with sensitivity, specificity, positive prediction value (PPV) and negative prediction value (NPV) of 92.3%, 66.7%, 33.3% and 98.0%, respectively. The nomogram based on preoperative CT images could achieve good predictive performance for STAS status of lung adenocarcinomas. This simple-to-used model can facilitate surgeons for a rational operation pattern choice at bedside.

Prognostic Nomograms Based on Ground Glass Opacity and Subtype of Lung Adenocarcinoma for Patients with Pathological Stage IA Lung Adenocarcinoma.

The value of lung adenocarcinoma (LUAD) subtypes and ground glass opacity (GGO) in pathological stage IA invasive adenocarcinoma (IAC) has been poorly understood, and reports of their association with each other have been limited. In the current study, we retrospectively reviewed 484 patients with pathological stage IA invasive adenocarcinoma (IAC) at Sun Yat-sen University Cancer Center from March 2011 to August 2018. Patients with at least 5% solid or micropapillary presence were categorized as high-risk subtypes. Independent indicators for disease-free survival (DFS) and overall survival (OS) were identified by multivariate Cox regression analysis. Based on these indicators, we developed prognostic nomograms of OS and DFS. The predictive performance of the two nomograms were assessed by calibration plots. A total of 412 patients were recognized as having the low-risk subtype, and 359 patients had a GGO. Patients with the low-risk subtype had a high rate of GGO nodules (p < 0.001). Multivariate Cox regression analysis showed that the high-risk subtype and GGO components were independent prognostic factors for OS (LUAD subtype: p = 0.002; HR 3.624; 95% CI 1.263–10.397; GGO component: p = 0.001; HR 3.186; 95% CI 1.155–8.792) and DFS (LUAD subtype: p = 0.001; HR 2.284; 95% CI 1.448–5.509; GGO component: p = 0.003; HR 1.877; 95% CI 1.013–3.476). The C-indices of the nomogram based on the LUAD subtype and GGO components to predict OS and DFS were 0.866 (95% CI 0.841–0.891) and 0.667 (95% CI 0.586–0.748), respectively. Therefore, the high-risk subtype and GGO components were potential prognostic biomarkers for patients with stage IA IAC, and prognostic models based on these indicators showed good predictive performance and satisfactory agreement between observational and predicted survival.

Significant difference in recurrence according to the proportion of high grade patterns in stage IA lung adenocarcinoma.

BackgroundPatients with early lung cancer are the best candidates for surgical resection. However, those patients with high grade patterns (micropapillary or solid) do not have a good prognosis, even if they have been diagnosed with stage I lung adenocarcinoma. A new modified grading system has been introduced and this study aimed to identify the prognostic role of the new grading system in patients with stage IA lung adenocarcinoma.MethodsPatients with pathological stage IA lung adenocarcinoma, according to the eighth TNM classification who underwent curative resection, were reviewed. The pathological data of stage IA adenocarcinoma was reviewed 1 (grade 1: lepidic predominant with no or less than 20% of high grade patterns, grade 2: acinar or papillary predominant with no or less than 20% of high grade patterns, grade 3: any tumor with 20% or more of high grade patterns). Prognostic factors were analyzed for disease‐free interval (DFI) and overall survival (OS) using Cox proportional models.ResultsThe medical records of 429 patients with stage IA lung adenocarcinoma were reviewed. DFI (p < 0.001) and OS (p < 0.001) were significantly lower in patients diagnosed with grade 3 compared with grade 1 and grade 2. Multivariate analysis showed that smoking (p = 0.013), value of SUVmax (p = 0.005), lymphovascular invasion (p = 0.004) and grade 3 (p = 0.008) were significant prognostic factors for DFI.ConclusionsThe proportion of high grade patterns showed a different prognosis, even if curative resection had been performed for stage IA adenocarcinoma. This new grading system is more simple and useful in the prediction of a prognosis in patients with stage IA lung adenocarcinoma.

Tumor Differentiation and EGFR Mutation Associated with Disease-Free Survival in Stage IA Lung Adenocarcinoma Patients with Curative Surgery.

BackgroundNearly 30% of stage IA non-small-cell lung cancer patients eventually die of recurrence or metastasis. This study aimed to predict stage IA lung adenocarcinoma (LADC) patients who underwent radical resection with a high risk of recurrence or metastasis.MethodsInformation on clinicopathological, genetic and therapeutic features and recurrence status was collected in this retrospective and two-center study. A nomogram based on multivariate analysis was established to predict disease-free survival. Further stratification was performed to identify populations with a high risk of relapse.ResultsA total of 1584 patients with pathological stage IA LADC who underwent radical surgery between 2011 and 2015 were enrolled from two medical institutions in this study. The nomogram including tumor differentiation and EGFR mutation had a higher C-index of 0.880 (95% CI 0.833–0.926) compared to 0.598 (95% CI 0.486–0.711) for the AJCC 8th TNM staging system. Furthermore, the C-index for the validation cohort was 0.798 (95% CI 0.738–0.857). In addition, the 3-year cumulative nonrecurrence rate in the high-risk group stratified by this model was 21.8% compared to 98.1% in the low-risk group.ConclusionThis study proposed a new nomogram including tumor differentiation and EGFR mutation to predict recurrence or metastatic probability in stage IA LADC patients who underwent radical surgery. This nomogram could identify patients in the high-risk group and help guide adjuvant treatment in the future.

Angiogenesis as a prognostic factor of pathological stage IA lung adenocarcinoma: developing an angiogenic score

Angiogenesis as a prognostic factor of pathological stage IA lung adenocarcinoma: developing an angiogenic score

Prognostic significance of blood and lymphatic vessel invasion in pathological stage IA lung adenocarcinoma in the 8th edition of the TNM classification

ObjectivesThe prognostic significance of blood and lymphatic vessel invasion in the 8th edition of the Tumor, Node, Metastasis (TNM) classification remains unclear. Therefore, this study aimed to evaluate the prognostic significance of blood and lymphatic vessel invasion in p-stage IA lung adenocarcinoma in the 8th edition of the TNM classification. Materials andmethodsWe retrospectively examined patients with p-Stage 0-IA lung adenocarcinoma, reclassified according to the 8th edition of the TNM classification. Blood and lymphatic vessel invasion were evaluated using hematoxylin-eosin and Elastica van Gieson and hematoxylin-eosin and anti-podoplanin antibody staining, respectively. Combined blood and lymphatic vessel invasion constituted tumor vessel invasion (TVI). ResultsOverall, 306 patients were evaluated. The median follow-up period was 98.0 (range: 10–216) months. The 5-year recurrence-free survival differed significantly among patients with and without TVI in p-stage IA1 (TVI−: 100%, TVI+: 88.9%, P = 0.007) and IA2 (TVI−: 94.6%, TVI+: 80.8%, P = 0.012) but not in p-stage IA3 (TVI−: 66.7%, TVI+: 75.0%, P = 0.598). The 5-year lung cancer-specific survival also differed significantly among those with and without TVI in p-stage IA1 (TVI−: 100%, TVI+: 88.9%, P < 0.001) and IA2 (TVI−: 98.2%, TVI+: 88.7%, P = 0.043) but not in p-Stage IA3 (TVI−: 66.7%, TVI+: 75.0%, P = 0.858). No recurrence and lung cancer-specific deaths occurred in p-stage IA1 patients without TVI. On multivariate analysis, the presence of TVI was independently associated with recurrence and lung cancer-specific death in patients with p-stage IA1-2 lung adenocarcinoma. TVI did not affect the prognosis of those with p-stage IA3 adenocarcinoma. ConclusionTVI is a prognostic factor in patients with p-stage IA1-2 lung adenocarcinoma. P-stage IA1 lung adenocarcinoma without TVI may therefore be classified as minimally invasive.

Advanced Lung Cancer Inflammation Index Predicts Outcomes of Patients with Pathological Stage IA Lung Adenocarcinoma Following Surgical Resection.

Purpose: The correlation of advanced cancer with inflammation and/or nutrition factors is well known. Recently, the advanced lung cancer inflammation index (ALI) was developed as a new prognostic tool for patients with advanced lung cancer. In this study, we examined whether ALI results are correlated with prognosis of patients with early stage lung adenocarcinoma who undergo lung resection.Methods: From January 2009 to December 2014, 544 patients underwent lung resection due to primary lung cancer at Dokkyo Medical University Hospital, of whom 166 with pathological stage IA lung adenocarcinoma were retrospectively investigated in this study. ALI was calculated as follows: Body Mass Index (BMI; kg/m2) × albumin (g/dL)/neutrophil- to-lymphocyte ratio (NLR).Results: Multivariate analysis revealed that gender, red cell distribution width (RDW), NLR, and ALI were parameters significantly correlated with overall survival (OS). Patients with an ALI value less than 22.2 had an inferior 5-year OS rate as compared to those with a value of 22.2 or higher (p <0.001) as well as an inferior 5-year recurrence-free survival (RFS) rate (p <0.001).Conclusion: Low ALI was correlated with poor prognosis in patients with stage IA lung adenocarcinoma. Those with an ALI value less than 22.2 should be carefully followed regardless of cancer stage.

P2.09-26 Clinical Significance of Subcellular Localization of Maspin in Patients with Pathological Stage IA Lung Adenocarcinoma

P2.09-26 Clinical Significance of Subcellular Localization of Maspin in Patients with Pathological Stage IA Lung Adenocarcinoma

P2.16-49 Which Nomogram is More Reliable to Predict Recurrence of Pathological Stage IA Lung Adenocarcinoma Treated by Surgery?

P2.16-49 Which Nomogram is More Reliable to Predict Recurrence of Pathological Stage IA Lung Adenocarcinoma Treated by Surgery?

P2.09-27 Prognostic Significance of Vascular Invasion in Pathological Stage IA Lung Adenocarcinoma According to the 8th Edition of the TNM Classification

Vascular invasion, including blood vessel invasion (v) and lymphatic vessel invasion (ly), is not a prognostic factor according to the 8th Edition of the Tumor-node-metastasis (TNM) Classification, and the prognostic impact of vascular invasion remains unclear. We reported the prognostic significance of vascular invasion classified according to the previous 7th Edition in patients with stage I non-small cell lung cancer (Diagn Pathol. 2015;10:17). The aim of the present study was to clarify whether vascular invasion classified in the 8th Edition has a prognostic impact on patients with pathological stage IA lung adenocarcinoma and should thus be adopted as an upstaging factor. We reviewed 314 patients with pathological IA (T1a-1bN0 according to the UICC-TNM Classification of Malignant Tumours, 7th Edition) lung adenocarcinoma completely resected between 2000 and 2005. We excluded patients with mucinous adenocarcinoma. The pathological invasive size was measured on the maximal cut surface of the primary tumor, stained with hematoxylin-eosin (HE) and elastica van Gieson (EVG), in all cases. We evaluated blood vessel invasion using specimens stained with HE and EVG, and lymphatic vessel invasion using specimens stained with HE and anti-podoplanin antibody. Blood vessel invasion and lymphatic vessel invasion together represented tumor vessel invasion (TVI). Survival curves were plotted using the Kaplan–Meier method, and the statistical significance of differences between the groups was determined by the log-rank test. The patients were stratified according to the 8th edition into Tis (N = 46), T1mi (N = 69), T1a (N = 82), T1b (N = 99), T1c (N = 18). The median follow-up period was 98.0 months. The recurrence-free survival rate at 5 years was 100%, 100%, 88.9%, 94.7%, 80.3%, 66.7%, and 66.7% in stage 0, IA1(TVI-), IA1(TVI+), IA2(TVI-), IA2(TVI+), IA3(TVI-), and IA3(TVI+), respectively. The lung cancer-specific survival rate at 5 years was 100%, 100%, 88.9%, 98.2%, 87.4%, 66.7%, and 66.7% in stage 0, IA1(TVI-), IA1(TVI+), IA2(TVI-), IA2(TVI+), IA3(TVI-) and IA3(TVI+), respectively. The presence of TVI was a poor prognostic factor in stage IA1 and IA2, but not in stage IA3. TVI is a prognostic factor in patients with lung adenocarcinoma measuring 20 mm or less in the pathological invasive size. Stage IA1 lung adenocarcinoma without TVI can possibly be classified as minimally invasive, because patients with stage IA1 lung adenocarcinoma have 100% recurrence-free survival and lung cancer-specific survival.

Clinical Significance of Subcellular Localization of Maspin in Patients with Pathological Stage IA Lung Adenocarcinoma.

Maspin is a tumor-suppressor protein and its prognostic value in lung adenocarcinoma has been reported. However, little is known about the clinical impact of subcellular localization of maspin in early-stage lung adenocarcinoma. We aimed to evaluate the clinical significance of subcellular localization of maspin in patients with pathological stage (p-stage) IA lung adenocarcinoma categorized by the new eighth edition TNM classification. We immunohistochemically analyzed 181 tissue samples from p-stage IA1 (n=37), IA2 (n=92) and IA3 (n=52) lung adenocarcinomas using antibody for maspin. The 181 cases fell into five predominant subtypes: lepidic (n=32), acinar (n=97), papillary (n=30), solid (n=20) and micropapillary (n=2). The frequencies of maspin staining were: cytoplasmic-only in 24.9%; pancellular (nuclear and cytoplasmic) in 8.8%; nuclear-only in 0.6%; no staining in 65.7%. Cytoplasmic-only staining significantly correlated with high pathological T-classification (p=0.039), lymphatic invasion (p=0.002) and poorer tumor differentiation (p=0.002). The patients were followed-up for 12-151 months (median=74 months), and the cytoplasmic-only staining significantly correlated with shorter disease-free survival (DFS) (p=0.034) and disease-specific survival (DSS) (p=0.036) by log-rank tests. In Cox's multivariate analysis, lymphatic invasion had the most significant effect on shorter DFS and DSS. The expression of maspin in the cytoplasm alone could be useful for predicting unfavorable prognoses in patients with p-stage IA lung adenocarcinoma.

Podoplanin expression in cancer-associated fibroblasts predicts unfavourable prognosis in patients with pathological stage IA lung adenocarcinoma.

Podoplanin expression in cancer-associated fibroblasts (CAFs) has been proposed as an unfavourable indicator in squamous cell carcinoma of the lung, but little is known about its clinical significance in early-stage lung adenocarcinoma. We evaluated the prognostic impact of podoplanin expression in patients with pathological stage (p-stage) IA lung adenocarcinoma as categorised by the 8th edition of the tumour-node-metastasis classification for lung cancer. Immunohistochemical analyses using anti-podoplanin antibody were performed on resected specimens from 158 patients with p-stage IA lung adenocarcinoma. When more than 10% of cancer cells or CAFs showed immunoreactivity with podoplanin, the specimens were classified as podoplanin-positive. Podoplanin-positive status in cancer cells (n = 8) was not correlated with clinicopathological factors or with patient prognosis. Podoplanin-positive status in CAFs (n = 41) was correlated significantly with poorer tumour differentiation (P < 0.001), the presence of lymphatic invasion (P < 0.001) and high-grade (solid and/or micropapillary) components constituting ≥1% of the entire tumour (P < 0.001). The log-rank test showed that podoplanin-positive status in CAFs was associated significantly with shorter disease-free survival (DFS) (P < 0.001) and disease-specific survival (P = 0.015). In Cox's multivariate analysis, podoplanin-positive status in CAFs had the most significant effect on shorter DFS [hazard ratio (HR) = 4.411, P = 0.004], followed by the presence of high-grade components (HR = 3.581, P = 0.013). Podoplanin expression in CAFs could be an independent predictor of increased risk of recurrence in patients with p-stage IA lung adenocarcinoma.

P1.02-061 Podoplanin Expression in Cancer-Associated Fibroblasts Predicts Unfavorable Prognosis in Patients with Stage IA Adenocarcinoma

Podoplanin expression in cancer-associated fibroblasts (CAFs) has been proposed as an unfavourable indicator in squamous cell carcinoma of the lung, but little is known about its clinical significance in early-stage lung adenocarcinoma. The aim of the present study was to evaluate the prognostic impact of podoplanin expression in patients with pathological stage IA lung adenocarcinoma classified by the new tumor-node-metastasis (TNM) system.

Does the histologic predominance of pathological stage IA lung adenocarcinoma influence the extent of resection?

We studied whether histologic subtype according to the new IASLC/ATS/ERS adenocarcinoma classification influences the extent of resection in patients with pathological stage IA lung adenocarcinoma. Data on 288 patients with pathological stage IA lung adenocarcinoma were analyzed retrospectively. Recurrence-free survival (RFS) rates were compared according to clinicopathological characteristics, including predominant histologic subtype and extent of resection. Median follow-up was 38.9months. Lobectomy was performed in 146 patients, and sublobar resection in 142 patients. When recurrence was compared among the low-grade group (adenocarcinoma in situ, AIS; minimally invasive adenocarcinoma, MIA), intermediate-grade group (lepidic, acinar, and papillary) and high-grade group (solid and micropapillary), the RFS rate decreased as the grade increased (p=0.037). There was no recurrence in the low-grade or lepidic predominant groups. The recurrence pattern did not differ according to the type of resection or histological subtype. Even in the intermediate- and high-grade groups, the extent of resection was not significantly related to the RFS rate (p=0.622, p=0.516). The results were unchanged after adjusting for independent risk factors. The concordance rate between clinical and pathological stage IA was good in low (98.6%) and intermediate grade (84.6%) and poor in high grade (41.2%). AIS, MIA, and lepidic predominant may be curable by any type of complete resection. Even in invasive subtypes, lobectomy does not offer a recurrence-free advantage over sublobar resection. However, in the high-grade group, less than half of clinical stage IA was actually pathological stage IA. Physicians should exercise caution whenever sublobar resection is planned.

Prognostic Impact of FDG-PET in Surgically Treated Pathological Stage I Lung Adenocarcinoma

This retrospective study evaluated whether the maximum standardized uptake value (SUVmax) on 18F-deoxyglucose (FDG)-positron emission tomography (PET) could be used to predict the prognosis of patients with pathological stage I adenocarcinoma. We analyzed 138 consecutive patients with pathological stage IA or IB lung adenocarcinoma except pure bronchioloalveolar carcinoma (BAC) who underwent preoperative FDG-PET imaging and curative resection from January 2005 to October 2010. We analyzed associations between disease-free survival (DFS) and clinicopathological factors. The 5-year DFS rate was 77.7%. Twenty two patients (15.9%) developed recurrence after surgery. Multivariate analysis identified SUVmax and lymphovascular (ly) involvement as the independent prognostic factors for recurrence (p = 0.0255 and p = 0.0333, respectively). We divided the patients into groups according to SUVmax and ly involvement. The 5-year DFS rate was 97.0% in patients with SUVmax ≤2.5 and without ly involvement, 100% with both SUVmax ≤2.5 and ly involvement, 70.2% with SUVmax >2.5 and without ly involvement, and 53.1% with both SUVmax >2.5 and ly involvement. The results of this study suggest that SUVmax and ly involvement could be used to predict the prognosis of patients with pathological stage I adenocarcinoma. The combination of these prognostic factors could also identify high risk groups of recurrence.

Why Do Pathological Stage IA Lung Adenocarcinomas Vary from Prognosis?: A Clinicopathologic Study of 176 Patients with Pathological Stage IA Lung Adenocarcinoma Based on the IASLC/ATS/ERS Classification

Patients with pathological stage IA adenocarcinoma (AC) have a variable prognosis, even if treated in the same way. The postoperative treatment of pathological stage IA patients is also controversial. We identified 176 patients with pathological stage IA AC who had undergone a lobectomy and mediastinal lymph node dissection at the Shanghai Chest Hospital, Shanghai, China, between 2000 and 2006. No patient had preoperative treatment. The histologic subtypes of all patients were classified according to the 2011 International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) international multidisciplinary lung AC classification. Patients' 5-year overall survival (OS) and 5-year disease-free survival (DFS) were calculated using Kaplan-Meier and Cox regression analyses. One hundred seventy-six patients with pathological stage IA AC had an 86.6% 5-year OS and 74.6% 5-year DFS. The 10 patients with micropapillary predominant subtype had the lowest 5-year DFS (40.0%).The 12 patients with solid predominant with mucin production subtype had the lowest 5-year OS (66.7%). Univariate and multivariate analysis showed that sex and prognositic groups of the IASLC/ATS/ERS histologic classification were significantly associated with 5-year DFS of pathological stage IA AC. Our study revealed that sex was an independent prognostic factor of pathological stage IA AC. The IASLC/ATS/ERS classification of lung AC identifies histologic categories with prognostic differences that could be helpful in clinical therapy.