Objective： Although many clinical studies on skip lymphatic metastasis in non-small cell lung cancer have been reported, the risk factors for skip lymphatic metastasis are still controversy and debatable. This study ...Objective： Although many clinical studies on skip lymphatic metastasis in non-small cell lung cancer have been reported, the risk factors for skip lymphatic metastasis are still controversy and debatable. This study investigated, by multivariate logistic regression analysis, the clinical features of skip metastasis to mediastinal lymph nodes （N2） in non-small cell lung cancer 0NISCLC） patients. Methods： We collected the clinicopathological data of 256 pN2-NSCLC patients who underwent lobectomy plus systemic lymph node dissection in Fujian Medical University Union Hospital. The cases in the present study were divided into two groups： skip metastasis （N2 skip＋） and non- skip metastasis （N2 skip-）. A retrospective analysis of clinical pathological features of two groups was performed, rib determine an independent factor, multivariate logistic regression analysis was used to identify possible risk factors. Results： A total of 256 pN2-NSCLC patients were recruited. The analysis results showed that gender, pathologic types, surgery, pleural involvement, smoking history, age, tumor stages, and differentiation were not statistical significant factors impacting on skip metastasis in pN2-NSCLC （P〉0.05）, whereas tumor size was an independent factor for skip metastasis （P=0.02）. Conclusions： The rate of skip lymphatic metastasis increases in pN2-NSCLC patients, in accompany with an increased tumor size.展开更多
In order to investigate the clinical significance of 99mTc-Tetrofosmin （TF） scintigraphy in the evaluation of lung cancer and mediastinal lymphoid node involvement, 33 patients with pulmo- nary neoplasmas were subje...In order to investigate the clinical significance of 99mTc-Tetrofosmin （TF） scintigraphy in the evaluation of lung cancer and mediastinal lymphoid node involvement, 33 patients with pulmo- nary neoplasmas were subjected to both 99mTc-TF scintigraphies and CT scans in one week before their operations or puncturations. All the images were judged visually and the emission images were analyzed with semi-quantitative methods in addition. The results of each group were compared. There was marked difference in target/non-target （T/N） ratio between the lung cancer group and the benign lesion group （P〈0.001）. Moreover, in the lung cancer group, T/N ratio in tomographies was signifi- cantly higher than that in planar images （P〈0.01）. The sensitivity and accuracy of semi-quantitative analysis in 99mTc-TF SPECT were significantly higher than those of CT in the diagnosis of pulmonary neoplasmas （P〈0.05 and P〈0.01 respectively）, so was the sensitivity of 99mTc-TF SPECT vs CT in the diagnosis of mediastinal lymphoid node metastasis （P〈0.05）. It was also found that epidermoid squamous cell carcinomas and adenocarcinomas had a higher T/N ratio than in small cell carcinomas （P〈0.05）, and 2 h washout rate （WR） of adenocarcinomas was higher than that of epidermoid squamous cell carcinomas （P〈0.05）. In conclusion, 99mTc-TF scintigraphy showed a favorable diag- nostic accuracy in appraising lung cancers and mediastinal lymph node metastases. Furthermore semi-quantitative technology can improve the accuracy, and is potential to offer some information about histological type of the cancer tissue. Therefore, 99mTc-TF scintigraphy will be a useful tool in the diagnosis and staging of lung cancer.展开更多
Background： We want to establish a lobe-specific mediastinal lymphadenectomy protocol for solitary pulmonary nodules （SPNs） in non-small cell lung cancer （NSCLC）. Methods： We retrospectively analyzed 401 patient...Background： We want to establish a lobe-specific mediastinal lymphadenectomy protocol for solitary pulmonary nodules （SPNs） in non-small cell lung cancer （NSCLC）. Methods： We retrospectively analyzed 401 patients with pathological diagnoses of NSCLC who underwent lobectomy, bilobectomy, or pneumonectomy with systematic lymphadenectomy from March 2004 to June 2011 in our hospital. All of the patients enrolled had a SPN preoperatively. Information about the primary tumor location, lymph node metastasis, and other baseline data were collected. Stepwise logistic regression was used to identify the key factors indicating non-regional mediastinal lymph node metastases （NRM）. Results： Of the primary tumors, 117, 39, 74, 104, and 67 were in the right upper lung （RUL）, right middle lung （RML）, right lower lung （RLL）, left upper lung （LUL）, and left lower lung （LLL）, respectively. Stepwise regression showed that #2,4, #10,11, and #10,11 as well as #7 was the key lymph node station for RUL, LUL, and lower lobes： #2,4 [odds ratio （OR）=28.000, 95% confidence interval （CI）： 2.917-268.790, P=0.004] for RUL, #10,11 （OR=31.667, 95% CI： 2.502-400.833, P=0.008） for LUL, #10,11 （OR=19.540, 95% CI： 4.217-90.541, P〈0.001） and #7 （OR=7.395, 95% CI： 1.586-34.484, P=0.011） for lower lobes, respectively. Patients with tumors 〉2 cm rarely had NRM without primary regional mediastinal involvement. Conclusions： With rigid consideration, a lobe-specific lymphadenectomy is feasible in practice. This protocol can be used when the lobe-specific key nodes are negative in intraoperative frozen sections, especially for NSCLC diagnosed as SPN 〈2 cm preoperatively.展开更多
Background:Despite numerous previous studies,the consideration of tumor location as a prognostic factor in resectable non-small cell lung cancer(NSCLC)remains controversial.The present study analyzed the association b...Background:Despite numerous previous studies,the consideration of tumor location as a prognostic factor in resectable non-small cell lung cancer(NSCLC)remains controversial.The present study analyzed the association between tumor location and clinical outcome in patients with resectable NSCLC who had undergone lobectomy with systematic lymphadenectomy and who had presented with varying nodal statuses.Methods:The data from a cohort of 627 eligible patients treated in Sun Yat-sen University Cancer Center between January 2000 and December 2008 were retrospectively collected,and the nodal statuses of patients with different tumor locations were compared.Cox proportional hazards regression model was used to determine the independent factors related to cancer-specific survival(CSS).Results:Multivariate analysis demonstrated that left lower lobe(LLL)tumors[hazard ratio(HR):1.465,95%confidence interval(CI)1.090-1.969,P=0.011],lymph node metastasis(HR:2.742,95%CI 2.145-3.507,P<0.001),and a tumor size of>4 cm(HR:1.474,95%CI 1.151-1.888,P=0.002)were three independent prognosticators in patients with resectable NSCLC.However,LLL tumors were associated only with CSS in node-positive patients(HR:1.528,95%CI 1.015-2.301,P=0.042),and a tumor size of>4 cm was the only independent risk predictor in the node-negative subgroup(HR:1.889,95%CI 1.324-2.696,P<0.001).Conclusions:Tumor location is related to the long-term CSS of NSCLC patients with lymph node metastasis.LLL tumors may be upstaged in node-positive patients to facilitate an optimal treatment strategy.展开更多
Objective: To investigate pathologically the characteristics of lung cancer metastasis by mediastinal lymph node ways (N2). Methods: Of 398 lung cancer patients who underwent radical pulmonectomy and extensive lymph n...Objective: To investigate pathologically the characteristics of lung cancer metastasis by mediastinal lymph node ways (N2). Methods: Of 398 lung cancer patients who underwent radical pulmonectomy and extensive lymph node dissection, 160 patients were diagnosed as with N2 metastasis, their 352 groups of mediastinal lymph nodes invaded were subject to the pathological study. Results: Evidences showed that the N2 metastasis of lung cancer was very active. It appears as single group or multi-group or jumping-form metastasis, rating 41.2%, 58.8% and 29.3% respectively. In addition, the extension of N2 metastasis was large, the most concentrated site was the 7th group lymph node (48.8%), then the 4th, 3rd and 5th group, rating 45.6%, 31.3% and 25.6% respectively. The occurrence of N2 metastasis was highly correlated with the site, size, histopathological type and the grade of differentiation of the cancer. An another feature of N2 metastasis was the invasion of metastasized lymph node into the bronchial wall, especially in adenocarcinoma. Conclusion: In order to achieve the radical removal of tumor, it is necessary to dissect the lymph nodes of the hilar and upper and lower mediastinum at the homolateral thoracic cavity actively and completely; beside, attention may be paid to the bronchial wall invasion caused by the lymph nodes metastasized.展开更多
Since the latest revision of the TNM system reclassified T3N0 tumours into the ⅡB stage, N2 lesions became the major determinant of the ⅢA stage. Concerning the minority of patients with T3N1 tumours in this stage,
Objective: Increased numbers of removed lymph nodes (LN) are resulting in more accurate staging of the patient (Will-Rogers-Phenomenon). This study evaluates dependence of lymph node sample size to 1) Will-Rogers-Phen...Objective: Increased numbers of removed lymph nodes (LN) are resulting in more accurate staging of the patient (Will-Rogers-Phenomenon). This study evaluates dependence of lymph node sample size to 1) Will-Rogers-Phenomenom, 2) influence of sample size on overall survival and in?terms of 3) morbidity and mortality. Methods: 131 patients after pulmonary resection were?retrospectively analysed concerning surgery, number of removed lymph nodes, stage, complications and survival. Patients were stratified according to the median number of lymph nodes in two groups (A <12 lymph nodes and B ≥12 lymph nodes). Results: 5% of the patients had only local lymphadenectomy and in 14% a systematic lymphadenectomy was performed. 17% of the patients showed skip metastasis. Lymph node positivity was correlated to the number of removed lymph nodes (p = 0.003). The approximated median survival for UICC (Union internationale contre le cancer) stage I was 511, stage II 521 and stage III 290 days. Subgroup analysis of survival data showed in group A an approximated median survival at stage I of 495 days, at II 537 days and at III 451.5 days. Group B showed at stage I 675 days, at II 521 days and at III 221 days. There was no difference in complications and mortality. Conclusion: A too low sample size leads to understaging due to skip metastasis. Obligatory mediastinal lymph node sampling would decrease the risk of understaging due to skip metastasis and does not increase morbidity or complications. Lymph node sampling is not inferior concerning morbidity and survival in our patient collective. This study cannot recommend a minimum number of LN to be resected. The evaluated limit of 12 LN proves to be suitable as a guideline.展开更多
Objective: To develop and validate a radiomics-based predictive risk score(RPRS) for preoperative prediction of lymph node(LN) metastasis in patients with resectable non-small cell lung cancer(NSCLC).Methods: We retro...Objective: To develop and validate a radiomics-based predictive risk score(RPRS) for preoperative prediction of lymph node(LN) metastasis in patients with resectable non-small cell lung cancer(NSCLC).Methods: We retrospectively analyzed 717 who underwent surgical resection for primary NSCLC with systematic mediastinal lymphadenectomy from October 2007 to July 2016. By using the method of radiomics analysis, 591 computed tomography(CT)-based radiomics features were extracted, and the radiomics-based classifier was constructed. Then, using multivariable logistic regression analysis, a weighted score RPRS was derived to identify LN metastasis. Apparent prediction performance of RPRS was assessed with its calibration,discrimination, and clinical usefulness.Results: The radiomics-based classifier was constructed, which consisted of 13 selected radiomics features.Multivariate models demonstrated that radiomics-based classifier, age group, tumor diameter, tumor location, and CT-based LN status were independent predictors. When we assigned the corresponding score to each variable,patients with RPRSs of 0-3, 4-5, 6, 7-8, and 9 had distinctly very low(0%-20%), low(21%-40%), intermediate(41%-60%), high(61%-80%), and very high(81%-100%) risks of LN involvement, respectively. The developed RPRS showed good discrimination and satisfactory calibration (C-index: 0.785, 95% confidence interval(95% CI):0.780-0.790)Additionally, RPRS outperformed the clinicopathologic-based characteristics model with net reclassification index(NRI) of 0.711(95% CI: 0.555-0.867).Conclusions: The novel clinical scoring system developed as RPRS can serve as an easy-to-use tool to facilitate the preoperatively individualized prediction of LN metastasis in patients with resectable NSCLC. This stratification of patients according to their LN status may provide a basis for individualized treatment.展开更多
Objective: Advances in diagnostic imaging techniques, such as 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), have led to greater accuracy in preoperative mediastinal staging for patients with non-small...Objective: Advances in diagnostic imaging techniques, such as 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), have led to greater accuracy in preoperative mediastinal staging for patients with non-small-cell lung cancer (NSCLC), but surgical staging remains the “gold standard” for diagnosis. A proper understanding of the current accuracy of diagnostic imaging is needed for further improvements. Methods: Forty-three patients who underwent resection for NSCLC involving mediastinal lymph node (MLN) metastasis at our hospital between June 2003 and May 2011 were enrolled in this study. We conducted a retrospective study of the radiological and pathological findings for 53 metastatic MLNs in the 43 patients. Results: The preoperative imaging modality was computed tomography (CT) alone for 18 patients (22 MLNs) and CT and FDG-PET for 25 patients (31 MLNs). The sensitivities of CT and FDG-PET were 41.5% and 58.0%, respectively. The sensitivity of CT did not differ according to any clinicopathological factors, but the sensitivity of FDG-PET tended to be higher for primary tumors with high SUVmax values and for non-adenocarcinomas. In the lymph nodes, all micrometastatic foci ≤ 2 mm were PET-negative, but 4 lymph nodes with metastatic foci larger than 10 mm were also PET-negative. Conclusions: For the diagnostic imaging of MLN, FDG-PET has a greater sensitivity than contrast-enhanced CT based on “size criteria”, but it is still not sufficiently sensitive and is influenced by various factors. At present, histological confirmation of MLNs is necessary when making decisions regarding treatment plans and the type of surgical procedure that should be performed.展开更多
文摘Objective： Although many clinical studies on skip lymphatic metastasis in non-small cell lung cancer have been reported, the risk factors for skip lymphatic metastasis are still controversy and debatable. This study investigated, by multivariate logistic regression analysis, the clinical features of skip metastasis to mediastinal lymph nodes （N2） in non-small cell lung cancer 0NISCLC） patients. Methods： We collected the clinicopathological data of 256 pN2-NSCLC patients who underwent lobectomy plus systemic lymph node dissection in Fujian Medical University Union Hospital. The cases in the present study were divided into two groups： skip metastasis （N2 skip＋） and non- skip metastasis （N2 skip-）. A retrospective analysis of clinical pathological features of two groups was performed, rib determine an independent factor, multivariate logistic regression analysis was used to identify possible risk factors. Results： A total of 256 pN2-NSCLC patients were recruited. The analysis results showed that gender, pathologic types, surgery, pleural involvement, smoking history, age, tumor stages, and differentiation were not statistical significant factors impacting on skip metastasis in pN2-NSCLC （P〉0.05）, whereas tumor size was an independent factor for skip metastasis （P=0.02）. Conclusions： The rate of skip lymphatic metastasis increases in pN2-NSCLC patients, in accompany with an increased tumor size.
文摘In order to investigate the clinical significance of 99mTc-Tetrofosmin （TF） scintigraphy in the evaluation of lung cancer and mediastinal lymphoid node involvement, 33 patients with pulmo- nary neoplasmas were subjected to both 99mTc-TF scintigraphies and CT scans in one week before their operations or puncturations. All the images were judged visually and the emission images were analyzed with semi-quantitative methods in addition. The results of each group were compared. There was marked difference in target/non-target （T/N） ratio between the lung cancer group and the benign lesion group （P〈0.001）. Moreover, in the lung cancer group, T/N ratio in tomographies was signifi- cantly higher than that in planar images （P〈0.01）. The sensitivity and accuracy of semi-quantitative analysis in 99mTc-TF SPECT were significantly higher than those of CT in the diagnosis of pulmonary neoplasmas （P〈0.05 and P〈0.01 respectively）, so was the sensitivity of 99mTc-TF SPECT vs CT in the diagnosis of mediastinal lymphoid node metastasis （P〈0.05）. It was also found that epidermoid squamous cell carcinomas and adenocarcinomas had a higher T/N ratio than in small cell carcinomas （P〈0.05）, and 2 h washout rate （WR） of adenocarcinomas was higher than that of epidermoid squamous cell carcinomas （P〈0.05）. In conclusion, 99mTc-TF scintigraphy showed a favorable diag- nostic accuracy in appraising lung cancers and mediastinal lymph node metastases. Furthermore semi-quantitative technology can improve the accuracy, and is potential to offer some information about histological type of the cancer tissue. Therefore, 99mTc-TF scintigraphy will be a useful tool in the diagnosis and staging of lung cancer.
文摘Background： We want to establish a lobe-specific mediastinal lymphadenectomy protocol for solitary pulmonary nodules （SPNs） in non-small cell lung cancer （NSCLC）. Methods： We retrospectively analyzed 401 patients with pathological diagnoses of NSCLC who underwent lobectomy, bilobectomy, or pneumonectomy with systematic lymphadenectomy from March 2004 to June 2011 in our hospital. All of the patients enrolled had a SPN preoperatively. Information about the primary tumor location, lymph node metastasis, and other baseline data were collected. Stepwise logistic regression was used to identify the key factors indicating non-regional mediastinal lymph node metastases （NRM）. Results： Of the primary tumors, 117, 39, 74, 104, and 67 were in the right upper lung （RUL）, right middle lung （RML）, right lower lung （RLL）, left upper lung （LUL）, and left lower lung （LLL）, respectively. Stepwise regression showed that #2,4, #10,11, and #10,11 as well as #7 was the key lymph node station for RUL, LUL, and lower lobes： #2,4 [odds ratio （OR）=28.000, 95% confidence interval （CI）： 2.917-268.790, P=0.004] for RUL, #10,11 （OR=31.667, 95% CI： 2.502-400.833, P=0.008） for LUL, #10,11 （OR=19.540, 95% CI： 4.217-90.541, P〈0.001） and #7 （OR=7.395, 95% CI： 1.586-34.484, P=0.011） for lower lobes, respectively. Patients with tumors 〉2 cm rarely had NRM without primary regional mediastinal involvement. Conclusions： With rigid consideration, a lobe-specific lymphadenectomy is feasible in practice. This protocol can be used when the lobe-specific key nodes are negative in intraoperative frozen sections, especially for NSCLC diagnosed as SPN 〈2 cm preoperatively.
基金funded by the Guangdong Provincial Science and Technology Project(Grant No.2013B021800070)
文摘Background:Despite numerous previous studies,the consideration of tumor location as a prognostic factor in resectable non-small cell lung cancer(NSCLC)remains controversial.The present study analyzed the association between tumor location and clinical outcome in patients with resectable NSCLC who had undergone lobectomy with systematic lymphadenectomy and who had presented with varying nodal statuses.Methods:The data from a cohort of 627 eligible patients treated in Sun Yat-sen University Cancer Center between January 2000 and December 2008 were retrospectively collected,and the nodal statuses of patients with different tumor locations were compared.Cox proportional hazards regression model was used to determine the independent factors related to cancer-specific survival(CSS).Results:Multivariate analysis demonstrated that left lower lobe(LLL)tumors[hazard ratio(HR):1.465,95%confidence interval(CI)1.090-1.969,P=0.011],lymph node metastasis(HR:2.742,95%CI 2.145-3.507,P<0.001),and a tumor size of>4 cm(HR:1.474,95%CI 1.151-1.888,P=0.002)were three independent prognosticators in patients with resectable NSCLC.However,LLL tumors were associated only with CSS in node-positive patients(HR:1.528,95%CI 1.015-2.301,P=0.042),and a tumor size of>4 cm was the only independent risk predictor in the node-negative subgroup(HR:1.889,95%CI 1.324-2.696,P<0.001).Conclusions:Tumor location is related to the long-term CSS of NSCLC patients with lymph node metastasis.LLL tumors may be upstaged in node-positive patients to facilitate an optimal treatment strategy.
文摘Objective: To investigate pathologically the characteristics of lung cancer metastasis by mediastinal lymph node ways (N2). Methods: Of 398 lung cancer patients who underwent radical pulmonectomy and extensive lymph node dissection, 160 patients were diagnosed as with N2 metastasis, their 352 groups of mediastinal lymph nodes invaded were subject to the pathological study. Results: Evidences showed that the N2 metastasis of lung cancer was very active. It appears as single group or multi-group or jumping-form metastasis, rating 41.2%, 58.8% and 29.3% respectively. In addition, the extension of N2 metastasis was large, the most concentrated site was the 7th group lymph node (48.8%), then the 4th, 3rd and 5th group, rating 45.6%, 31.3% and 25.6% respectively. The occurrence of N2 metastasis was highly correlated with the site, size, histopathological type and the grade of differentiation of the cancer. An another feature of N2 metastasis was the invasion of metastasized lymph node into the bronchial wall, especially in adenocarcinoma. Conclusion: In order to achieve the radical removal of tumor, it is necessary to dissect the lymph nodes of the hilar and upper and lower mediastinum at the homolateral thoracic cavity actively and completely; beside, attention may be paid to the bronchial wall invasion caused by the lymph nodes metastasized.
文摘Since the latest revision of the TNM system reclassified T3N0 tumours into the ⅡB stage, N2 lesions became the major determinant of the ⅢA stage. Concerning the minority of patients with T3N1 tumours in this stage,
文摘Objective: Increased numbers of removed lymph nodes (LN) are resulting in more accurate staging of the patient (Will-Rogers-Phenomenon). This study evaluates dependence of lymph node sample size to 1) Will-Rogers-Phenomenom, 2) influence of sample size on overall survival and in?terms of 3) morbidity and mortality. Methods: 131 patients after pulmonary resection were?retrospectively analysed concerning surgery, number of removed lymph nodes, stage, complications and survival. Patients were stratified according to the median number of lymph nodes in two groups (A <12 lymph nodes and B ≥12 lymph nodes). Results: 5% of the patients had only local lymphadenectomy and in 14% a systematic lymphadenectomy was performed. 17% of the patients showed skip metastasis. Lymph node positivity was correlated to the number of removed lymph nodes (p = 0.003). The approximated median survival for UICC (Union internationale contre le cancer) stage I was 511, stage II 521 and stage III 290 days. Subgroup analysis of survival data showed in group A an approximated median survival at stage I of 495 days, at II 537 days and at III 451.5 days. Group B showed at stage I 675 days, at II 521 days and at III 221 days. There was no difference in complications and mortality. Conclusion: A too low sample size leads to understaging due to skip metastasis. Obligatory mediastinal lymph node sampling would decrease the risk of understaging due to skip metastasis and does not increase morbidity or complications. Lymph node sampling is not inferior concerning morbidity and survival in our patient collective. This study cannot recommend a minimum number of LN to be resected. The evaluated limit of 12 LN proves to be suitable as a guideline.
基金supported by the National Key Research and Development Plan of China (No. 2017YFC1309100)the National Natural Scientific Foundation of China (No. 81771912, 81901910, and 81701782)the Provincial Science and Technology Plan Project of Guangdong Province (No. 2017B020227012)
文摘Objective: To develop and validate a radiomics-based predictive risk score(RPRS) for preoperative prediction of lymph node(LN) metastasis in patients with resectable non-small cell lung cancer(NSCLC).Methods: We retrospectively analyzed 717 who underwent surgical resection for primary NSCLC with systematic mediastinal lymphadenectomy from October 2007 to July 2016. By using the method of radiomics analysis, 591 computed tomography(CT)-based radiomics features were extracted, and the radiomics-based classifier was constructed. Then, using multivariable logistic regression analysis, a weighted score RPRS was derived to identify LN metastasis. Apparent prediction performance of RPRS was assessed with its calibration,discrimination, and clinical usefulness.Results: The radiomics-based classifier was constructed, which consisted of 13 selected radiomics features.Multivariate models demonstrated that radiomics-based classifier, age group, tumor diameter, tumor location, and CT-based LN status were independent predictors. When we assigned the corresponding score to each variable,patients with RPRSs of 0-3, 4-5, 6, 7-8, and 9 had distinctly very low(0%-20%), low(21%-40%), intermediate(41%-60%), high(61%-80%), and very high(81%-100%) risks of LN involvement, respectively. The developed RPRS showed good discrimination and satisfactory calibration (C-index: 0.785, 95% confidence interval(95% CI):0.780-0.790)Additionally, RPRS outperformed the clinicopathologic-based characteristics model with net reclassification index(NRI) of 0.711(95% CI: 0.555-0.867).Conclusions: The novel clinical scoring system developed as RPRS can serve as an easy-to-use tool to facilitate the preoperatively individualized prediction of LN metastasis in patients with resectable NSCLC. This stratification of patients according to their LN status may provide a basis for individualized treatment.
文摘Objective: Advances in diagnostic imaging techniques, such as 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), have led to greater accuracy in preoperative mediastinal staging for patients with non-small-cell lung cancer (NSCLC), but surgical staging remains the “gold standard” for diagnosis. A proper understanding of the current accuracy of diagnostic imaging is needed for further improvements. Methods: Forty-three patients who underwent resection for NSCLC involving mediastinal lymph node (MLN) metastasis at our hospital between June 2003 and May 2011 were enrolled in this study. We conducted a retrospective study of the radiological and pathological findings for 53 metastatic MLNs in the 43 patients. Results: The preoperative imaging modality was computed tomography (CT) alone for 18 patients (22 MLNs) and CT and FDG-PET for 25 patients (31 MLNs). The sensitivities of CT and FDG-PET were 41.5% and 58.0%, respectively. The sensitivity of CT did not differ according to any clinicopathological factors, but the sensitivity of FDG-PET tended to be higher for primary tumors with high SUVmax values and for non-adenocarcinomas. In the lymph nodes, all micrometastatic foci ≤ 2 mm were PET-negative, but 4 lymph nodes with metastatic foci larger than 10 mm were also PET-negative. Conclusions: For the diagnostic imaging of MLN, FDG-PET has a greater sensitivity than contrast-enhanced CT based on “size criteria”, but it is still not sufficiently sensitive and is influenced by various factors. At present, histological confirmation of MLNs is necessary when making decisions regarding treatment plans and the type of surgical procedure that should be performed.
