New staging system: how does it affect our practice?

Composition of the sputum bacterial microbiome of patients with different pathomorphological forms of non-small-cell lung cancer

Recent studies have shown that the bacterial microbiome of the respiratory tract influences the development of lung cancer. Changes in the composition of the microbiome are observed in patients with chronic inflammatory processes. Such microbiome changes may include the occurrence of bacteria that cause oxidative stress and that are capable of causing genome damage in the cells of the host organism directly and indirectly. To date, the composition of the respiratory microbiome in patients with various histological variants of lung cancer has not been studied. In the present study, we determined the taxonomic composition of the sputum microbiome of 52 patients with squamous cell carcinoma of the lung, 52 patients with lung adenocarcinoma and 52 healthy control donors, using next-generation sequencing (NGS) on the V3-V4 region of the bacterial gene encoding 16S rRNA. The sputum microbiomes of patients with different histological types of lung cancer and controls did not show significant differences in terms of the species richness index (Shannon); however, the patients differed from the controls in terms of evenness index (Pielou). The structures of bacterial communities (beta diversity) in the adenocarcinoma and squamous cell carcinoma groups were also similar; however, when analyzed according to the matrix constructed by the Bray-Curtis method, there were differences between patients with squamous cell carcinoma and healthy subjects, but not between those with adenocarcinoma and controls. Using the LEFse method it was possible to identify an increase in the content of Bacillota (Streptococcus and Bacillus) and Actinomycetota (Rothia) in the sputum of patients with squamous cell carcinoma when compared with samples from patients with adenocarcinoma. There were no differences in the content of bacteria between the samples of patients with adenocarcinoma and the control ones. The content of representatives of the genera Streptococcus, Bacillus, Peptostreptococcus (phylum Bacillota), Prevotella, Macellibacteroides (phylum Bacteroidota), Rothia (phylum Actinomycetota) and Actinobacillus (phylum Pseudomonadota) was increased in the microbiome of sputum samples from patients with squamous cell carcinoma, compared with the control. Thus, the sputum bacterial microbiome of patients with different histological types of non-small-cell lung cancer has significant differences. Further research should be devoted to the search for microbiome biomarkers of lung cancer at the level of bacterial species using whole-genome sequencing.

Sputum Microbiome Composition in Patients with Squamous Cell Lung Carcinoma

Background: Recent findings indicate that the host microbiome can have a significant impact on the development of lung cancer by inducing an inflammatory response, causing dysbiosis, and generating genome damage. The aim of this study was to search for bacterial communities specifically associated with squamous cell carcinoma (LUSC). Methods: In this study, the taxonomic composition of the sputum microbiome of 40 men with untreated LUSC was compared with that of 40 healthy controls. Next-Generation sequencing of bacterial 16S rRNA genes was used to determine the taxonomic composition of the respiratory microbiome. Results: There were no differences in alpha diversity between the LUSC and control groups. Meanwhile, differences in the structure of bacterial communities (β diversity) among patients and controls differed significantly in sputum samples (pseudo-F = 1.53; p = 0.005). Genera of Streptococcus, Bacillus, Gemella, and Haemophilus were found to be significantly enriched in patients with LUSC compared to the control subjects, while 19 bacterial genera were significantly reduced, indicating a decrease in beta diversity in the microbiome of patients with LUSC. Conclusions: Among other candidates, Streptococcus (Streptococcus agalactiae) emerges as the most likely LUSC biomarker, but more research is needed to confirm this assumption.

Taxonomic diversity of sputum microbiome in lung cancer patients and its relationship with chromosomal aberrations in blood lymphocytes

Here we report a pilot-sized study to compare the taxonomic composition of sputum microbiome in 17 newly-diagnosed lung cancer (LC) patients and 17 controls. Another object was to compare the representation of individual bacterial genera and species in sputum with the frequency of chromosomal aberrations in the blood lymphocytes of LC patients and in controls. Both groups were male; average age 56.1 ± 11.5 in patients and 55.7 ± 4.1 in controls. Differences in the species composition of bacterial communities in LC patients and controls were significant (pseudo-F = 1.94; p = 0.005). Increased prevalence in LC patients was detected for the genera Haemophilus and Bergeyella; whereas a decrease was observed for the genera Atopobium, Stomatobaculum, Treponema and Porphyromonas. Donors with high frequencies of chromosomal aberrations had a significant reduction in the microbiome of representatives of the genus Atopobium in the microbiome and a simultaneous increase in representatives of the species Alloprevotella compared to donors with a low level of chromosomal aberrations in lymphocytes. Thus, a comparison of the bacterial composition in the sputum of donors with cytogenetic damages in theirs lymphocytes, warrants further investigations on the potential role of microorganisms in the process of mutagenesis in somatic cells of the host body.

Signaling protein signature predicts clinical outcome of non-small-cell lung cancer

BACKGROUND

Non-small-cell lung cancer (NSCLC) is characterized by abnormalities of numerous signaling proteins that play pivotal roles in cancer development and progression. Many of these proteins have been reported to be correlated with clinical outcomes of NSCLC. However, none of them could provide adequate accuracy of prognosis prediction in clinical application.

METHODS

A total of 384 resected NSCLC specimens from two hospitals in Beijing (BJ) and Chongqing (CQ) were collected. Using immunohistochemistry (IHC) staining on stored formalin-fixed paraffin-embedded (FFPE) surgical samples, we examined the expression levels of 75 critical proteins on BJ samples. Random forest algorithm (RFA) and support vector machines (SVM) computation were applied to identify protein signatures on 2/3 randomly assigned BJ samples. The identified signatures were tested on the remaining BJ samples, and were further validated with CQ independent cohort.

RESULTS

A 6-protein signature for adenocarcinoma (ADC) and a 5-protein signature for squamous cell carcinoma (SCC) were identified from training sets and tested in testing sets. In independent validation with CQ cohort, patients can also be divided into high- and low-risk groups with significantly different median overall survivals by Kaplan-Meier analysis, both in ADC (31 months vs. 87 months, HR 2.81; P <  0.001) and SCC patients (27 months vs. not reached, HR 9.97; P <  0.001). Cox regression analysis showed that both signatures are independent prognostic indicators and outperformed TNM staging (ADC: adjusted HR 3.07 vs. 2.43, SCC: adjusted HR 7.84 vs. 2.24). Particularly, we found that only the ADC patients in high-risk group significantly benefited from adjuvant chemotherapy (P = 0.018).

CONCLUSIONS

Both ADC and SCC protein signatures could effectively stratify the prognosis of NSCLC patients, and may support patient selection for adjuvant chemotherapy.

Survival Impact of Stations of Pathological Lymph Nodes in N2 Non-small Cell Lung Cancer in a French Hospital

BACKGROUND

The prognosis of lung cancer remains poor; only 20% of patients can undergo surgery. N2 non-small cell lung cancer (NSCLC) is a heterogeneous disease. We conducted a retrospective study to analyze the impact of N2 location on survival.

METHODS

This study included 342 NSCLC with N2 involvement between 1988 and 2014. Patient-related data were collected through the CRB biobank and included demographic, therapeutic, and survival data. Survival was analyzed according to Kaplan-Maier method. Cox's regression analysis and analysis of variance (ANOVA) were used to determine factors significantly associated with survival.

RESULTS

The population average age was 61.6 years; 82.2% were men, a majority were former smokers (87.1%), and 45.3% had adenocarcinoma. The main prognostic factors were male gender (p = 0.01), number of nodes (p < 0.0001), and tumor size (p < 0.0001). N2 disease had a poor survival (16 months) compared with N0 (32 months) and N1 (21.1 months) disease (p < 0.0001). The patients with involvement of station 4 (survival = 17.8 months) seemed to have a prognosis between those with station 7 (survival = 10.5 months) and N1 (survival = 22.6 months), p = 0.0005.

CONCLUSIONS

N2 location has a prognostic impact in surgically NSCLC, and station 4 involvement has a better prognostic than station 7.

Multimodality Treatment of Advanced Non-small Cell Lung Cancer: Where are we with the Evidence?

PURPOSE OF REVIEW

The majority of patients with non-small cell lung cancer (NSCLC) present with advanced disease and overall survival rates are poor. This article outlines the current and outstanding evidence for the use of multimodality treatment in this group of patients, including in combination with an increasing number of treatment options, such as immunotherapy and genotype-targeted small molecule inhibitors.

RECENT FINDINGS

Optimal therapy for surgically resectable stage III disease remains debatable and currently the choice of treatment reflects each individual patient's disease characteristics and the expertise and opinion of the thoracic multi-disciplinary team. Evidence for a distinct oligometastatic state in which improved outcomes can be achieved remains minimal and there is as yet no consensus definition for oligometastatic lung cancer. Whilst there is supporting evidence for the aggressive management of isolated metastases, the use of consolidative therapy for multiple metastases remains unproven.

SUMMARY

Evolution of new RT technologies, improved surgical technique and a plethora of interventional-radiology-guided ablative therapies are widening the choice of available treatment modalities to patients with NSCLC. In the setting of resectable locally advanced disease and the oligometastatic state, there is a growing need for randomised comparison of the available treatment modalities to guide both treatment and patient selection.

Polymorphisms of GSTM1, GSTT1, GSTP1 genes and chromosomal aberrations in lung cancer patients

PURPOSE

To study the potential links between genetic polymorphisms in the GSTT1, GSTM1, GSTP1 genes and the frequency of chromosomal aberrations (CAs) in lung cancer patients and healthy residents in Russian Federation.

METHODS

200 cells in well-spread metaphase with 46 chromosomes were examined for 353 newly diagnosed lung cancer patients (males) who received medical treatment in the Kemerovo Regional Oncology Center (Kemerovo, Russian Federation), and 300 healthy males from Kemerovo, Russian Federation. The polymorphisms of the GSTM1 del and GSTT1 del genes were analysed by multiplex PCR. Genotyping of the polymorphic variants in the GSTP1 (A313G, T341C) gene was performed using Real-time PCR with competing TaqMan probes complementary to the polymorphic DNA sites. The data analysis was performed using software STATISTICA 8.0 (StatSoft Inc., USA).

RESULTS

We discovered that a GSTM1 del polymorphism increases the frequency of chromosomal damage in smoking patients with lung cancer, a general group of lung cancer patients, donors with non-small cell lung cancer and patients in the latest stages of the malignant process. The synergetic effects of occupational exposure and the malignant process can induce some modifications in the cytogenetic status in lung cancer patients harbouring the GSTM1 del polymorphism.

CONCLUSIONS

CAs in peripheral blood lymphocytes can be used as biomarkers of the early biological effects of exposure to genotoxic carcinogens and may predict future cancer incidence in several epidemiologic studies. Genetic changes in genes encoding phase II detoxification enzymes are linked to decreases in the metabolic detoxification of environmentally derived genotoxic carcinogens.

Manganese Oxide-Coated Carbon Nanotubes As Dual-Modality Lymph Mapping Agents for Photothermal Therapy of Tumor Metastasis

Lymph node (LN) status is a major indicator of stage and survival of lung cancer patients. LN dissection is a primary option for lung cancer LN metastasis; however, this strategy elicits adverse effects and great trauma. Therefore, developing a minimally invasive technique to cure LN metastasis of lung cancer is desired. In this study, multiwalled carbon nanotubes (MWNTs) coated with manganese oxide (MnO) and polyethylene glycol (PEG) (namely MWNTs-MnO-PEG) was employed as a lymphatic theranostic agent to diagnose and treat metastatic LNs. After single local injection and lymph drainage were performed, regional LNs were clearly mapped by T1-weighted magnetic resonance (MR) of MnO and dark dye imaging of MWNTs. Meanwhile, metastatic LNs could be simultaneously ablated by near-infrared (NIR) irradiation under the guidance of dual-modality mapping. The excellent result was obtained in mice bearing LNs metastasis models, showing that MWNTs-MnO-PEG as a multifunctional theranostic agent was competent for dual-modality mapping guided photothermal therapy of metastatic LNs.

Predicting the prognosis of lung cancer: the evolution of tumor, node and metastasis in the molecular age-challenges and opportunities

The tumor, node and metastasis (TNM) classification of malignant tumors was proposed by Pierre Denoit in the mid-20(th) century to code the anatomic extent of tumors. Soon after, it was accepted by the Union for International Cancer Control and by the American Joint Committee on Cancer, and published in their respective staging manuals. Till 2002, the revisions of the TNM classification were based on the analyses of a database that included over 5,000 patients, and that was managed by Clifton Mountain. These patients originated from North America and almost all of them had undergone surgical treatment. To overcome these limitations, the International Association for the Study of Lung Cancer proposed the creation of an international database of lung cancer patients treated with a wider range of therapeutic modalities. The changes introduced in the 7(th) edition of the TNM classification of lung cancer, published in 2009, derived from the analysis of an international retrospective database of 81,495 patients. The revisions for the 8(th) edition, to be published in 2016, will be based on a new retrospective and prospective international database of 77,156 patients, and will mainly concern tumor size, extrathoracic metastatic disease, and stage grouping. These revisions will improve our capacity to indicate prognosis and will make the TNM classification more robust. In the future the TNM classification will be combined with non-anatomic parameters to define prognostic groups to further refine personalized prognosis.

Implementing effective and sustainable multidisciplinary clinical thoracic oncology programs

Three models of care are described, including two models of multidisciplinary care for thoracic malignancies. The pros and cons of each model are discussed, the evidence supporting each is reviewed, and the need for more (and better) research into care delivery models is highlighted. Key stakeholders in thoracic oncology care delivery outcomes are identified, and the need to consider stakeholder perspectives in designing, validating and implementing multidisciplinary programs as a vehicle for quality improvement in thoracic oncology is emphasized. The importance of reconciling stakeholder perspectives, and identify meaningful stakeholder-relevant benchmarks is also emphasized. Metrics for measuring program implementation and overall success are proposed.

The seventh tumour-node-metastasis staging system for lung cancer: Sequel or prequel?

Anatomical cancer extent is an important predictor of prognosis and determines treatment choices. In non-small-cell lung cancer (NSCLC) the tumour–node–metastasis (TNM) classification developed by Pierre Denoix replaced in 1968 the Veterans Administration Lung cancer Group (VALG) classification, which was still in use for small-cell lung cancer (SCLC). Clifton Mountain suggested several improvements based on a database of mostly surgically treated United States (US) patients from a limited number of centres. This database was pivotal for a uniform reporting of lung cancer extent by the American Joint Committee of Cancer (AJCC) and the International Union against Cancer (IUCC), but it suffered increasingly from obsolete diagnostic and staging procedures and did not reflect new treatment modalities. Moreover, its findings were not externally validated in large Japanese and European databases, resulting in persisting controversies which could not be solved with the available database. The use of different mediastinal lymph-node maps in Japan, the (US) and Europe facilitated neither the exchange nor the comparison of treatment results.

Peter Goldstraw, a United Kingdom (UK) thoracic surgeon, started the process of updating the sixth version in 1996 and brought it to a good end 10 years later. His goals were to improve the TNM system in lung cancer by addressing the ongoing controversies, to validate the modifications and additional descriptors, to validate the TNM for use in staging SCLC and carcinoid tumours, to propose a new uniform lymph-node map and to investigate the prognostic value of non-anatomical factors. A staging committee was formed within the International Association for the Study of Lung Cancer (IASLC) – which supervised the collection of the retrospective data from >100,000 patients with lung cancer – treated throughout the world between 1990 and 2000, analyse them with the help of solid statistics and validate externally with the Surveillance, Epidemiology and End Results (SEER) database.

The ten modifications and the mediastinal lymph-node map – which were proposed in 2007 and adopted by the AJCC and IUCC in their respective seventh revision of the TNM system – were implemented as of 2010 and were rapidly adopted by the thoracic oncology community and cancer registries. As expected, not all controversies could be fully addressed, and the need for a prospective data set containing more granular information was felt early on. This data set of 25,000 consecutive incident cases will form the base for the eighth revision in 2017 and is currently being collected. Other threats are the role of stage migration and the increasing number of biological factors interfering with disease extent for prognostication. The latter issue will be addressed by the creation of a prognostic index, including several prognostic factors, of which stage will be one.

For the time being, the seventh TNM classification is considered the gold standard for the description of disease extent, initial treatment allocation and the reporting of treatment results. The uniform use of the TNM descriptors and the lymph-node map by all involved in lung cancer care is to be considered a process indicator of quality.

Role of adjuvant radiotherapy in completely resected non-small-cell lung cancer

Most long-term survivors of non-small-cell lung cancer (NSCLC) are patients who have had a completely resected tumour. However, this is only achievable in about 30% of the patients. Even in this highly selected group of patients, there is still a high risk of both local and distant failure. Adjuvant treatments such as chemotherapy (CT) and radiotherapy (RT) have therefore been evaluated in order to improve their outcome. In patients with stage II and III, administration of adjuvant platinum-based chemotherapy is now considered the standard of care, based on level 1 evidence. The role of postoperative radiation therapy (PORT) remains controversial. In the PORT meta-analysis published in 1998, the conclusions were that if PORT was detrimental to patients with stage I and II completely resected NSCLC, the role of PORT in the treatment of tumours with N2 involvement was unclear and further research was warranted. Thus at present, after complete resection, adjuvant radiotherapy should not be administered in patients with early lung cancer. Recent retrospective and non-randomised studies, as well as subgroup analyses of recent randomised trials evaluating adjuvant chemotherapy, provide evidence of the possible benefit of PORT in patients with mediastinal nodal involvement. The role of PORT needs to be evaluated also for patients with proven N2 disease who undergo neoadjuvant chemotherapy followed by surgery. The risk of local recurrence for N2 patients varies between 20% and 60%. Based on currently available data, PORT should be discussed for fit patients with completely resected NSCLC with N2 nodal involvement, preferably after completion of adjuvant chemotherapy or after surgery if patients have had preoperative chemotherapy. There is a need for new randomised evidence to reassess PORT using modern three-dimensional conformal radiation technique, with attention to normal organ sparing, particularly lung and heart, to reduce the possible over-added toxicity. Quality assurance of radiotherapy as well as quality of surgery – and most particularly nodal exploration modality – should both be monitored. A new large multi-institutional randomised trial Lung ART evaluating PORT in this patient population is needed and is now under way.

Immune therapy of non-small cell lung cancer. The future

Surgery is still the best treatment option of lung cancer but only one third of patients are operable and prognosis remains mediocre in operated patients, with the exception of initial stages. Medical treatment is fast moving toward new frontiers. New insights in the biology of cancer development led to discovery of new drugs, which are more effective as compared to conventional platinum based chemotherapy. A new approach to immunotherapy based on immune-check point represents a remarkable innovation in lung cancer treatment. Initial trials with anti PD-1 antibodies in metastatic patients provided results never observed with previously known drug categories. Several key question need to be answered to identify patients most likely to respond to anti PD-1/anti PD-L1 treatments, to assess the role of combined treatment modalities including immune check point receptor block (associations with surgery, chemotherapy, ITKs), and to boost host immune response, possibly by lowering his systemic inflammation and improving nutritional status.

Staging of lung cancer

Primary lung cancer is the leading cause of cancer mortality in the world. Thorough clinical staging of patients with lung cancer is important, because therapeutic options and management are to a considerable degree dependent on stage at presentation. Radiologic imaging is an essential component of clinical staging, including chest radiography in some cases, computed tomography, MRI, and PET. Multiplanar imaging modalities allow assessment of features that are important for surgical, oncologic, and radiation therapy planning, including size of the primary tumor, location and relationship to normal anatomic structures in the thorax, and existence of nodal and/or metastatic disease.

New molecular staging with G-factor supplements TNM classification in gastric cancer: a multicenter collaborative research by the Japan Society for Gastroenterological Carcinogenesis G-Project committee

BACKGROUND

The G-Project committee was erected by the Japan Society for Gastroenterological Carcinogenesis with an aim of establishing a new classification scheme based on molecular biological characteristics that would supplement the conventional TNM classification to better predict outcome.

METHODS

In a literature search involving 822 articles on gastric cancer, eight molecules including p53, vascular endothelial growth factor (VEGF)-A, VEGF-C, matrix metalloproteinase-7 (MMP-7), human epidermal growth factor receptor 2, Regenerating islet-derived family, member 4, olfactomedin-4 and Claudin-18 were selected as candidates to be included in the new molecular classification scheme named G-factor. A total of 210 cases of gastric cancer who underwent curative R0 resection were registered from four independent facilities. Immunohistochemical staining for the aforementioned molecules was performed for the surgically resected specimens of the 210 cases to investigate the correlation between clinicopathological factors and expression of each molecule.

RESULTS

No significant correlation was observed between the immunostaining expression of any of the eight factors and postoperative recurrence. However, the expressions of p53 and MMP-7 were significantly correlated with overall survival (OS). When 210 gastric cancer patients were divided into three groups based on the expression of p53 and MMP-7 (G0 group: negative for both p53 and MMP-7, n = 69, G1 group: positive for either p53 or MMP-7, n = 97, G2 group: positive for both of the molecules, n = 44), G2 group demonstrated significantly higher recurrence rate (59%) compared to 38% in G0 (p = 0.047). The multivariate regression analysis revealed that G2 group was independently associated with a shorter disease-free survival (DFS) (hazard ratio 1.904, 95% CI 1.098-3.303; p = 0.022), although the association with OS was not significant. Stage II patients among the G2 group had significantly inferior prognosis both in terms of OS and DFS when compared with those among the G0/G1 group, with survival curves similar to those of Stage III cases.

CONCLUSIONS

G-factor based on the expression of p53 and MMP-7 was found to be a promising factor to predict outcome of Stage II/III gastric cancer, and possibly to help select the treatment for Stage II cancer, thus supplementing the conventional TNM system.

Extended resections of non-small cell lung cancers invading the aorta, pulmonary artery, left atrium, or esophagus: can they be justified?

T4 tumors that invade the heart, great vessels, or esophagus comprise a heterogenous group of locally invasive lung cancers. Prognosis depends on nodal status; this relationship has been consistently demonstrated in many of the small series of extended resection. Current National Comprehensive Cancer Network guidelines do not recommend surgery for T4 extension with N2-3 disease (stage IIIB). However, biopsy-proven T4 N0-1 (stage IIIA) may be operable. Localized tumors with invasion of the aorta, pulmonary artery, left atrium, or esophagus represent a small subset of T4 disease. Acquiring sufficient randomized data to provide statistical proof of a survival advantage for patients undergoing extended resections for these neoplasms will likely never be possible.Therefore, we are left to critically analyze current documented experience to make clinical decisions on a case-by-case basis.It is clear that the operative morbidity and mortality of extended resections for locally advanced T4 tumors have significantly improved over time,yet the risks are still high. The indications for such procedures and the anticipated outcomes should be clearly weighed in terms of potential perioperative complications and expertise of the surgical team. Patients with T4 N0-1 have the best prognosis and with complete resection may have the potential for cure. The use of induction therapy and surgery for advanced T4 tumors may improve survival. Current data suggest that for tumors that invade the aorta, pulmonary artery,left atrium, or esophagus, resection should be considered in relation to multidisciplinary care.For properly selected patients receiving treatment at high volume, experienced centers, extended resections may be warranted.

Log odds of positive lymph nodes are superior to other measures for evaluating the prognosis of non-small cell lung cancer

BACKGROUND

To evaluate the ability of the log odds of positive lymph nodes to predict prognosis in patients with non-small cell lung cancer (NSCLC).

METHODS

Correlations between the log odds of positive lymph nodes, numbers of dissected lymph nodes, dissected lymph node stations, positive lymph nodes, positive lymph node ratio, and positive lymph node stations were retrospectively evaluated using Pearson correlation coefficients (r), survival analysis by Kaplan-Meier, Cox hazard ratio model, and log-rank tests.

RESULTS

The numbers of dissected lymph nodes, positive lymph nodes, dissected lymph node stations and positive lymph node stations significantly correlated with the log odds of positive lymph nodes (P < 0.001, P < 0.001, P = 0.002 and P < 0.001, respectively). The five-year survival ratio of postoperative patients with the log odds of positive lymph nodes <11.412 and >-1.412 were 63.9% and 32.5%, respectively (P < 0.001). According to multivariate analysis, age and log odds of positive lymph nodes are independent risk factors for overall survival (hazard ratio = 2.660, 95% confidence interval 2.114-3.346, P < 0.001). A new staging system featuring a combination of log odds of positive lymph nodes and a tumor node metastasis (TNM) staging system was established for predicting survival.

CONCLUSION

The log odds of positive lymph nodes are superior to the positive lymph node ratio and p-N-stage for predicting prognosis of NSCLC. A new staging system that combines log odds of positive lymph nodes and the current TNM staging system predicts prognosis more accurately than the TNM system alone.

Reevaluation of survival and prognostic factors in pathologic stage I lung adenocarcinoma by the new 2009 TNM classification

The incidence of lung adenocarcinoma has been increased significantly year by year. In this histologic type, complete surgical resection is commonly chosen as treatment method at the initial stages. However, the postoperative survival rate remains unsatisfactory even within the stage I. The purpose of this study is to investigate the factors related with prognosis in stage I lung adenocarcinoma after surgical resection. In this manuscript, a retrospective study was performed. Survival rates were calculated by the Kaplan-Meier method, and for multivariate analyses, Cox proportional hazards regression model was used. The results indicated that a total of 531 patients were included. Overall 5-year survival was 81.2 %. Age, sex, pathologic stage, T category, tumor size, differentiation, necrosis, visceral pleural invasion (VPI), lymphatic vessel or vascular invasion, and serum carcinoembryonic antigen (CEA) were significantly associated with 5-year overall survival of the patients with Kaplan-Meier analysis. Moreover, on multivariate analyses, seven variables were shown to be independent prognostic factors, including differentiation (hazard ratios (HR), 1.357), VPI (HR, 0.551), lymphatic vessel or vascular invasion (HR, 0.533), necrosis (HR, 1.671), age (HR, 1.519), pathological stage (HR, 4.477), and CEA (HR, 2.099). In conclusion, the most important prognostic factor is pathologic stage. Other adverse prognostic factors include differentiation, VPI, lymphatic vessel or vascular invasion, necrosis, age, and CEA.