Study on the Relationship between Enhanced CT Scanning before Surgery and Lymph Node Metastasis of Patients with Non-small Cell Lung Cancer
|School||Southern Medical University,|
|Keywords||Non-small cell lung cancer Preoperative enhanced CT scan Surgery Lymph nodemetastasis|
Background:Lung cancer is currently the greatest threat to human life and health of malignancy. It is expected that the lung cancer patients in China will reach100million by2025, being the country that having the most patients with lung cancer around the world than any other country. Lung cancer mostly occur in people over the age of40, according to their biological characteristics are divided into small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). Patients with non-small cell lung cancer accounts for80%-85%of all lung cancer patients, combined therapy to surgery as the only means of non-small-cell lung cancer may be completely cured. Lung cancer whether the scope of its parts with mediastinal lymph node metastasis and metastasis, clinical stage, treatment options, and assess prognosis and efficacy, follow-up observation are very important. With the development of the medical examination of lung cancer means also follow the progress, but due to computed tomography (CT), especially enhanced CT can provide comprehensive primary lung lesions, intrathoracic lymph nodes, pleura, chest wall and upper abdominal anatomy information CT scan has become the most important tool for the clinical staging of lung cancer, is currently the main method for the clinical staging of lung cancer. In recent years, PET/PET-CT provides metabolic lesions and pathophysiology information, to make up for a CT scan provides only the defect of the lesion morphology information, especially for mediastinal lymph node metastasis judgment sensitivity, specificity than CT, but its high cost, is not widely used in the clinical diagnosis and treatment of lung cancer.Lymph drainage has certain rules, namely the right upper lobe of lung lymph flow right hilar and right upper mediastinal lymph node. Middle lobe of right lung lymph flow, lower lobe summary area of lymphoid tissue, subcarinal and right upper mediastinal lymph node. The lower lobe of the right lung, lower lobe to summary area, subcarinal, pulmonary ligament and the right superior mediastinum lymph gland. The left lung lymph node, the left lobe lymphatic lead to aortic arch anterior mediastinal lymph node. The lower lobe of the left lung lymph flow to the upper and lower leaf summary area, subcarinal and across the mediastinum to the right upper mediastinum lymph nodes. The rules suggest that lung cancer will have a certain amount of lymphatic drainage pathway:diffusion of right lung cancer begins with metastasis to ipsilateral hilar lymph node of the trend, and then shifted to the right paratracheal lymph nodes, and rarely transferred to the contralateral lymph node; but the left lung cancer in the ipsilateral lymph node metastasis often spread to the lateral lymph node.CT diagnosis of lymph node metastasis is generally determined by its size.At present, most of the researchers and clinicians diagnosis of normal mediastinal lymph node is set to1.0cm (measuring its short diameter); lymph node short diameter>1cm in CT image is diagnosed lymph node metastasis. The sensitivity, specificity, and accuracy of different reports in order to get the current diagnostic criteria will be different. Foreign Dwamena, Meta-analysis covers1990-199829studies,15studies observed CT mediastinal staging of NSCLC, they found that CT sensitivity is 60%, specificity of77%,75%accuracy rate. Nine studies on the evaluation of CT examination of mediastinal lymph node metastasis domestic Yang Jin-ji The analysis covers the period1999-2002, all of the research will mediastinal lymph node short diameter>1cm as positive standard CT scan, mediastinoscopy, and cross-sectional thoracic surgery to obtain the pathological findings as the standard for diagnosis of mediastinal lymph node metastasis, CT examination sensitivity47%, specificity of83%,75%accuracy rate. However, we think, to lymph node diameter as diagnostic node metastasis of CT lung carcinoma lymph standard has limitations, it is missing the CT check for other information we. Almost all researchers agree that the following views:pathological lymph nodes of normal size after the results may be positive, transfer and enlarged lymph nodes do not necessarily occur tumor. And Zhong Wenzhao thinks to lymph node short diameter as the diagnosis of lymph node metastasis in standard has certain limitations. The Tan Lilian study found that dynamic enhanced spiral CT scan can well show enhanced degree of lung cancer, and preliminary evaluation of tumor vascular endothelial growth factor (vascular endothelial growth factor, VEGF) expression and microvessel density (microvascular density, MVD) quantity, understand the status of tumor vessels, indirect evaluation of the malignant degree and transfer.Objectives:Preoperative assessment according to the imaging information of non-small cell lung cancer about mediastinal lymph node metastasis, the choice of the standardized treatment of lung cancer and prognosis judgment have extremely important significance. The previous comparative study on preoperative CT scan with postoperative lymph node biopsy results, mostly focused on CT displayed on lymph node size, such as tumor size, enhanced value, the location of the tumor and the location of lymph node where the enhanced CT shows, emphasis on such information was ignored.In this study, we retrospectively analyzed in recent years in212cases of non-small cell cancer preoperative enhancement results pathological lymph node CT findings and postoperative,we aim to study the information enhanced CT examination of providing in non-small cell lung cancer,we try to find out wether he information is associated with mediastinal lymph node metastasis.Methods:(1) Observed objectCardiothoracic Surgery, Zhujiang Hospital, Southern Medical University,from January2009to June2012,212cases of patients with non-small cell lung cancer surgery, before surgery enhanced CT examination. Male139cases, female73cases, aged31-74years, with a mean age of59.2±9.3years old. The amendments to the lymph nodes made by Mountain CF1997, is the basis of the mediastinal lymph node location distribution.All cases preoperative enhanced CT scan in our hospital, exclude contraindications underwent lung cancer resection and systematic mediastinal lymphadenectomy (SML).The right lung cleaning area including the trachea paratracheal lymph node, lymph nodes before and after, anterior mediastinal nodes, lower paratracheal lymph nodes, ascending aortic lymph node, subcarinal lymph node, paraesophageal lymph node, lymph nodes and pulmonary ligament focal pulmonary hilar lymph node, That is to say2,3,4,6,7,8,9,10groups of lymph nodes. The left lung cleaning area including the trachea paratracheal lymph node, lymph nodes before and after, lower paratracheal lymph node, lymph node under the aortic arch, ascending aortic lymph node, subcarinal lymph node, paraesophageal lymph node, lymph nodes and pulmonary ligament focal pulmonary hilar lymph node,That is to say2,3,4,5,6,7,8,9,10groups of lymph nodes..212cases of non-small cell lung cancer,159cases of lesions of peripheral lung cancer,53cases of central lung cancer.101cases of adenocarcinoma,80cases of squamous cell carcinoma,2cases of bronchioloalveolar carcinoma,13cases of adenosquamous carcinoma,11cases of large cell lung cancer,5cases of carcinoid tumors.We swept intrathoracic lymph nodes,3731lymph nodes in981groups during the operations, harvested lymph nodes per patient on average about17.6; pathologically confirmed the transfer of784lymph nodes in331groups, the ratio of lymph node metastasis is20.1%. We analysis patients’Enhanced CT scan results before their surgery and postoperative lymph node biopsy results.(2) ResearchFor212cases of postoperative pathological diagnosis of non-small cell lung cancer patients, we analysis the preoperative spiral CT imaging information, including cancer tumor size, cancer CT enhancement of the value, lymph node size, CT prompted intumescent lymph node’s location and four aspects of materials. Cancer tumor size group still refer to the size of the lung Cancer standard which is enacted by International Union Against Cancer, UICC, in2009. There are three groups:diameter<3cm, diameter is between3-7cm, tumor diameter over7cm.The judgment standard of CT diagnose in lung cancer with regional lymph node metastasis is to measure intumescent lymph node size which CT finds, refer to lymph nodes diameter of≥1cm as positive. To strengthen value15HU as the boundary value of the contrast enhanced CT value, enhanced CT value is less than15HU as its mild enhancement, greater than or equal to15HU to strengthen significantly. CT group situation points without lymph node enlargement, enlarged mediastinal lymph nodes, Hilum lymph node enlargement, pulmonary, mediastinal lymph node enlargement.Routine pathological method detection of lymph node metastasis is the main method of diagnosis of lymph node metastasis, clinical go up to the most commonly used method is single paraffin section of lymph node haematin eosin (HE) staining, according to the tumor cells and normal cells of different size, shape, color diagnosis, etc. The preoperative CT imaging characteristics and postoperative non-small cell lung cancer lymph node is the last stage to do one by one contrast, contrast analysis, evaluation of spiral CT examination diagnostic sensitivity, specificity and accuracy of mediastinal lymph node metastasis.(3) statistical methodsAll the information of the data are the Chinese version of the software by the SPSS13.0statistical analysis. Count data using the number of cases (percentage). Statistical methods:count data using χ2test groups were compared using the Log-rank test, multivariate regression analysis of the influencing factors, P<0.05indicates significant difference significant.ResultsBased on preoperative enhanced CT features of212patients with non-small cell lung cancer patients and postoperative lymph pathologic result, contrast analysis found that the size of the lymph node metastasis and lung lesions, CT shown in lymph node size and position lymph nodes (ie mediastinal lymph node grouping). Lung lesions greater, the greater the possibility of occurrence of lymph node metastasis (P <0.01). According to the results of this study,12patients with tumor diameter>7cm patients were12cases with lymph node metastasis positive, the positive rate was as high as100%. CT check to lymph node short diameter>1cm as positive standard, there are significant differences, but the short diameter≤1cm lymph nodes in patients with non-small cell lung cancer of the lymph node metastasis rate was48.4%. Study found that patients with non-small cell lung cancer CT cancer enhanced value node metastasis and no significant difference with lymph. The study found that non small cell lung cancer, the anatomical location and CT found that there is a close relationship between lymph node location, pulmonary hilar lymph node enlargement of the lymph node metastasis of non-small cell lung cancer patients was low, the research sample and insufficient number of related, but the CT found that enlarged mediastinal lymph nodes. The rate of lymph node metastasis was significantly increased, and lung cancer in the right upper lobe is more prone to mediastinal lymph node metastasis than in other parts, whether the tip of the left lung space occupying more should actively operation intervention required follow-up studies in further.ConclusionsMediastinal lymph node size variation and normal lymph node size of their parts have a certain relationship. CT diagnosis of lymph node metastasis in its size alone to determine, and prone to error, sensitivity, specificity, and accuracy of the different reports will be different. Through comparative analysis, we get the following view:1.Lymph node metastasis was associated with tumor sizes in patients with small cell lung cancer.Patients with tumor diameter≤3cm, regardless the size of lymph node of their CT shows, lymph node metastasis may exist. Lesion diameter more than7cm of the lung lesions in patients with suspected lung cancer, may also need high attention has no lymph node metastasis, must be enhanced further examination, including CT.2.Tumor enhanced value of CT examination of patients with non-small cell lung cancer with lymph node metastasis was no significant difference.3.CT examination of non-small cell lung cancer with lymph node, short diameter>1cm as positive standard has significant differences, but even in CT patients without lymph node enlargement still had a higher rate of lymph node metastasis, that rely on lymph node size was diagnosed with localized lung metastasis lymph node, prompted us to read non CT findings in patients with small cell lung cancer was enhanced when we must also pay attention to information in many aspects, a full assessment of the clinical stage of the tumor to choose the appropriate treatment. 4.In this group of cases, CT findings of non small cell lung cancer lymph singlet hilum of lung and lymph nodes metastasis rate is low, and the number of cases may be less relevant; CT showed enlarged mediastinal lymph nodes when the rate of lymph node metastasis was significantly increased, and the left upper lobe of lung lesions than other parts of the lung cancer more easily occurrence of mediastinal lymph node metastasis, whether the tip of the left lung space occupying more should actively operation intervention required follow-up studies further validate.