Utility of frozen-section evaluation of lymph nodes in the staging of bronchogenic carcinoma at mediastinoscopy and thoracotomy

We conducted a retrospective analysis of the utility of frozen-section diagnoses in determining lymph node status at mediastinoscopy in 122 consecutive patients with bronchogenic carcinoma. Thirty-five of 122 patients had one or more lymph nodes with frozen-section evaluation positive for metastatic carcinoma. Subsequent nodal sections not in the original frozen-section study revealed metastatic carcinoma in two additional patients. The false-negative rate was 1.6%. Sensitivity was 94.6%. Predictive value of negative frozen-section evaluation results was 97.7%. Because there were no false-positive frozen-section results, specificity and predictive value for positive results of frozen-section evaluation were 100%. The statuses of individual lymph nodes from these 122 patients were also evaluated. Six hundred twenty lymph nodes were sampled from the mediastinum at mediastinoscopy. Frozen-sections in 47 lymph nodes were positive. Subsequent nodal sections not in the original frozen-sections examination revealed metastatic carcinoma in four additional lymph nodes. The false-negative rate was 0.6%. Sensitivity was 92.2%. Predictive value of negative results from frozen-section evaluation was 99.3%. Because there were no false-positive frozen-section results, specificity and predictive value for positive results of frozen-section examination were 100%. We conclude that frozen-section evaluation of lymph nodes at mediastinoscopy reliably indicates lymph node status, thus enabling the physician to decide whether to proceed to thoracotomy. Thus staging of the carcinoma and definitive surgery can be accomplished during a single anesthetic procedure. Combining mediastinoscopy and thoracotomy with frozen-section diagnostic control also reduces both the length and cost of hospitalization.     

Computed tomography for the evaluation of intrathoracic invasion by lung cancer

We conducted computed tomographic examinations of the chest in 171 patients with lung cancer whose disease was subsequently surgically staged; routine mediastinal exploration was undertaken in all patients undergoing thoracotomy (151), and in 20 patients only anterior mediastinotomy or mediastinoscopy was performed. We have considered three groups of patients: In Group I (including all 171 patients) mediastinal lymph nodes were evaluated for metastatic involvement; nodes were considered diseased when greater than 1 cm. Sensitivity, specificity, and accuracy were 95%, 83%, and 89%. Among these 171 patients, 34 (Group II) had a central tumor otherwise considered operable, which was shown on plain roentgenograms to be in contact with the mediastinum; infiltration of hilar and mediastinal vessels and of mediastinal tissues was investigated preoperatively with computed tomography and then ascertained at thoracotomy. Sensitivity, specificity, and accuracy were 68%, 72% and 70%. Twenty-seven patients (Group III) had a peripheral tumor abutting the pleural surface and suspected to invade the parietal pleura and chest wall; patients with evident bone infiltration were excluded. Sensitivity, specificity, and accuracy of computed tomography were 50%, 90%, and 65%.     

Role of positron emission tomography in mediastinal lymphatic staging of non-small cell lung cancer.

OBJECTIVE: Positron emission tomography (PET) is used increasingly in staging of non-small cell lung cancer (NSCLC) as a non-invasive tool. The role of the PET in mediastinal lymphatic staging of NSCLC is not clear. We aimed to demonstrate the efficacy of PET in determining mediastinal lymphatic metastasis by comparing the results of PET with mediastinoscopy. PATIENTS AND METHODS: We performed PET preoperatively in 170 patients with clinically operable NSCLC between 2004 and 2006. Stations defined as metastasis by PET (SUV(max) >2.5) were recorded. Mediastinoscopy was performed initially in all patients and a total of 687 stations which can be reached with mediastinoscope were sampled (mean 4.04). Forty-three patients with mediastinal metastasis were referred to the oncology clinic for chemotherapy while lung resection and complete mediastinal lymphatic dissection through thoracotomy was performed in the remaining 127 patients. Involvement of mediastinal lymph nodes was verified to compare the sensitivity and specificity of mediastinoscopy and the related PET results. RESULTS: Histopathologic classification of the tumors revealed 79 squamous carcinomas and 58 adenocarcinomas. False positivity rate of PET was 26% (95% CI: 14-38), false negativity was 25% (95% CI: 18-33), sensitivity was 74% (95% CI: 63-86), specificity was 73% (95% CI: 66-82) and accuracy was 74% in mediastinal staging. Negative predictive value of mediastinoscopy was 94% (95% CI: 89-98), positive predictive value 100%, sensitivity 84% (95% CI: 74-94), specificity 100% and accuracy was 95%. CONCLUSION: PET results do not provide acceptable accuracy rates. Mediastinoscopy still remains the gold standard for mediastinal staging of NSCLC, although it cannot reach to all the mediastinal stations.     

Role of Mediastinoscopy in Pretreatment Staging of Patients with Primary Lung Cancer

Since the introduction of mediastinoscopy, there has been a great deal of discussion regarding indications for this technique and the significance of positive findings. We undertook this study to determine the role of clinical staging and the value of routine mediastinoscopy in the treatment selection of patients with primary lung cancer.From 1975 to 1983, 1,259 consecutive patients with proven and operable lung cancer underwent preresection mediastinoscopy. Nodes were sampled at three levels, and findings were recorded by location, invasiveness, and histology. There were no operative deaths, but 3 patients had a major complication.Mediastinoscopy was positive in 339 (27%) patients and negative in 920 (73%). In the group with positive findings, 303 patients had no operation because a curative resection was not possible (extranodal metastases, 180; location, 76; histology, 47). No patient survived 5 years, and only 4% survived 2 years. Of the 36 patients considered to have operable disease, 28 underwent resection with a projected 5-year survival of 18%. In the group with negative findings, 89% had a curative resection with a hospital mortality of 3.2% and 5-year survival of 53%. When results of mediastinoscopy were correlated with findings at thoracotomy, the sensitivity of the test was 93% on nodes in the superior mediastinum and the specificity, 100%.This study shows that mediastinoscopy is safe and is an accurate indicator of the presence or absence of tumor in superior mediastinal nodes. If positive nodes are found, a curative resection is generally not possible, thoracotomy is avoided, and the overall survival is low.     

Mediastinoscopy in patients with clinical stage I non-small cell lung cancer

BACKGROUND: The aim of this study was to investigate the significance of mediastinoscopy for clinical stage I non-small cell lung cancer. METHODS: We reviewed 291 patients who underwent mediastinoscopy from January 1995 to December 2001 for clinical stage I non-small cell lung cancer. The patients who presented tumor-negative lymph nodes on mediastinoscopy underwent thoracotomy for pulmonary resection and mediastinal lymph node dissection in the same operative session. Mediastinoscopy-positive patients were referred for neoadjuvant therapy. RESULTS: Of the 291 patients, 20 patients (6.9%) were found with N2 or N3 disease on mediastinoscopy. Among 271 mediastinoscopy-negative patients, thoracotomy-proven N0 was found in 201 patients (74.2%), N1 in 44 patients (16.2%), and N2 in 25 patients (9.2%). Seventeen of 25 patients with unforeseen N2 disease had positive lymph nodes in the station that could be approached by mediastinoscopy only. The positive rate of mediastinoscopy was significantly higher in the patients with nonbronchioloalveolar-type adenocarcinoma than in squamous cell carcinoma (11.5% vs 3.3%, p = 0.013). However, there was no difference in the mediastinoscopy-positive rate between clinical T1 and T2 status. CONCLUSIONS: Though there are still controversies about routine mediastinoscopy in patients without mediastinal nodal enlargement on chest computed tomography scan, this study demonstrates that routine mediastinoscopy is necessary, especially for nonbronchioloalveolar-type adenocarcinoma patients.     

The value of mediastinoscopy in preoperative staging of bronchogenic carcinoma

To determine more precisely the role of mediastinoscopy in the preoperative staging of bronchogenic carcinoma, we studied 85 patients in the period 1983 to 1985 and compared the results of mediastinoscopy and computed tomographic scanning with the findings at thoracotomy. Mediastinoscopy was performed in 48 patients when mediastinal nodes larger than 1 cm were found at computed tomographic scanning. Only 21 of them (44%) were found to have metastatic nodes. Of the remaining patients, 22 were operated on and two showed false negative results (9%). Mediastinoscopy had a sensitivity of 91% and a specificity of 100%. The positive predictive value of computed tomographic scanning was only 54%. Thirty-seven patients underwent thoracotomy after having negative computed tomographic scan results. Eleven of them (30%) were found to have metastatic mediastinal lymph nodes. The negative predictive value of computed tomographic scanning was 70%. When results from both series of patients were compared, the sensitivity and specificity of computed tomographic scanning proved to be 68% and 57%, respectively, with an accuracy of 61%. Because of the low accuracy rate of computed tomographic scanning, a more routine use of mediastinoscopy seems to be justified.     

Results of preoperative mediastinoscopy for small cell lung cancer

BACKGROUND: The significance of mediastinoscopy for small cell lung cancer is unclear owing to the small number of surgical cases. METHODS: To determine the N component of the TNM staging system, computed tomographic findings and the results of mediastinoscopy were compared with the pathologic examination of surgical specimens. RESULTS: Four cases among 37 patients (10.8%) were determined as inoperable by mediastinoscopy because of mediastinal lymph node metastasis. A thoracotomy was performed in 33 patients. Six patients (18.2%) who had been judged to have no metastasis by mediastinoscopy were found to have N2 disease after examination of the surgical specimens. In the identification of all mediastinal metastases, mediastinoscopy was 40.0% sensitive, 100% specific, and 83.8% accurate. When the superior mediastinal, paratracheal, pretracheal, tracheobronchial, and subcarinal lymph nodes were defined as approachable nodes, mediastinoscopy was 66.7% sensitive, 100% specific, and 94.6% accurate in the evaluation of these restricted nodes. Four cases among 8 patients with cN1 lesions resulted in a designation as pN2. CONCLUSIONS: Mediastinoscopy is useful for the diagnosis of an approachable mediastinal lymph node in small cell lung cancer cases. This exploration is necessary for patients with small cell lung cancer who are diagnosed as cN1 before thoracotomy.     

支气管内超声引导针吸活检术在肺癌分期中的应用

目的 探讨支气管内超声引导针吸活检术(EBUS-TBNA)在肺癌分期中的应用价值.方法 回顾性总结2009年9月至2010年2月,52例胸部CT均发现纵隔淋巴结肿大≥1.0 cm肺癌病人经EBUS-TBNA检查的临床资料.结果 经EBUS-TBNA检查证实纵隔淋巴结转移(阳性)者41例,未见纵隔淋巴结转移(阴性)者11例.阳性者放弃手术,予以化疗.阴性者接受胸腔镜或开胸手术,行肺叶切除或肺楔形切除加纵隔淋巴结清扫.术后病理证实,9例纵隔淋巴结确实末见转移,2例纵隔淋巴结可见癌转移,即EBUS-TBNA检查假阴性.EBUS-TBNA的敏感性、特异性、准确性、阳性预测价值及阴性预测价值分别为95.3%、100%、96.2%、100%及81.8%.该检查耐受良好,无任何相关并发症发生.结论 EBUS-TBNA是一种安全、有效的肺癌分期方法.

Abstract：

Objective To determine the value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for staging of lung cancer. Methods The study was retrospective, a total of 52 patients underwent EBUSTBNA for known or suspected lung cancer. All patients were detected enlarged mediastinal lymph nodes on CT scan ( ≥ 1.0cm). Results Of the 52 patients, 41 patients were found with N2 or N3 disease on EBUS-TBNA. 11 patients with negative EBUS-TBNA underwent thoracoscopy or thoracotomy for pulmonary resection and mediastinal lymph node dissection, 9 patients were confirmed N0 by pathology, whereas 2 patients had metastatic lymph node. The diagnostic sensitivity, specificity, accuracy, positive predictive value and negative predictive value of EBUS-TBNA for the mediastinal staging of lung cancer were 95.3%, 100%, 96.2%, 100%, and 81.8%, respectively. The procedure was uneventful, and there were no postoperative complications. Conclusion EBUS-TBNA is an effective and safe technique for mediastinal staging in lung cancer patients.     

电视纵隔镜临床应用的初步体会

目的：探讨电视纵隔镜手术在临床应用中的价值。方法：回顾性总结2001年9月－2002年9月54例经电视纵隔镜手术患者的临床资料,其中颈部纵隔镜手术44例,胸骨旁纵隔镜手术6例,颈部加胸骨旁纵隔手术4例。术前未获得明确病理诊断的纵隔疾病18例;高度怀疑或已明确诊断为肺癌且影像学显示纵隔淋巴结肿大（直径＞1．0cm）者36例。结果：术前未获病理诊断的18例患者,经电视纵隔镜检查后17例取得明确诊断,确诊率为94．4％（17／18）;高度怀疑或病理已确诊为肺癌的36例,电视纵隔镜检查证实肿瘤纵隔淋巴结转移（阳性）22例,未见纵隔淋巴结转移（阴性）14例。阳性者放弃手术,予以化疗。阴性者均中转开胸行肺叶切除或肺楔型切除加纵隔淋巴结清扫。术后病理证实肺癌11例（纵隔淋巴结未见转移,与纵隔镜检查结果相符）,肺结核球、炎性假瘤和错构瘤各1例。本组纵隔镜手术后患者并发症发生率及病死率均为0。结论：电视纵隔镜手术更安全、可靠,可作为纵隔疑难疾病诊断和明确肺癌术前分期的常规方法。     

Clinical value of cervical mediastinoscopy in the staging of bronchial carcinoma

Whether mediastinoscopy is indicated in the preoperative staging of bronchogenic carcinoma is still a controversial issue. It may be performed routinely (to exclude locally inoperable patients from surgery), selectively, or it may be regarded as superfluous (in centers which prefer an extended lympho adenectomy at the time of thoracotomy). We regard mediastinoscopy as indicated for the following purposes: 1) staging of NSCLC and SCLC; 2) diagnostic (mediastinal masses or lung tumors without previous histology); 3) restaging after primary chemotherapy; 4) assessment of prognosis in patients with borderline operability. The indication for 224 mediastinoscopies performed at our institution in the period from September 1991 through March 1999 was mainly for staging (59.2%) or diagnostic (30.6%). Eight (5.4%) patients underwent mediastinoscopy for the assessment of operability, and 7 (4.8%) after primary chemotherapy for the restaging of loco-regionally advanced lung cancer. Sensitivity and specificity rates were 87% and 100%, respectively, with an accuracy of 93% for the mediastinoscopy performed for the staging of lung cancer at all stages. If we consider the N2 tumors (42 cases) alone, the sensitivity was 76.7% and the specificity 100%, with an accuracy of 83.3%. Overall positive and negative predictive value resulted 100% and 87%, respectively, according to the data reported in literature. Our data confirm the role of mediastinoscopy as the gold standard for regional staging of lung cancer.     

The Value of Radiographic and Computed Tomography in the Staging of Lung Carcinoma

A prospective double-blind study was undertaken to compare computed tomography (CT) and conventional radiographic tomography (RT) in the staging of lung carcinoma. Seventy-five patients had CT and RT of the mediastinum and hilum prior to operation. The presence or absence of metastasis to lymph nodes documented at the time of operation was the standard applied to the studies. CT correctly predicted the presence or absence of mediastinal lymphadenopathy in most cases (sensitivity 91%, specificity 94%), while RT was less helpful (sensitivity 61%, specificity 86%). Metastatic mediastinal lymph nodes in those patients with false negative CT and RT studies averaged only 0.8 cm in diameter, probably accounting for the negative radiographic findings. Both CT and RT had poor predictive values in detecting hilar lymphadenopathy (sensitivity 73% and 47%, specificity 87% and 72%, respectively).The predictive value of CT in the evaluation of mediastinal lymphadenopathy equaled that of mediastinoscopy or mediastinotomy. When CT of the mediastinum demonstrates no lymphadenopathy, invasive staging can be deferred for definitive thoracotomy. Since false positive values were seen with both CT and RT scans of the mediastinum (4% and 8%, respectively), invasive staging will still be necessary in those patients with positive studies.     

Mediastinal lymph node staging in suspected lung cancer: comparison of positron emission tomography with F-18-fluorodeoxyglucose and mediastinoscopy

BACKGROUND: In patients with bronchogenic carcinoma, mediastinal lymph node staging is essential for determining treatment options. In this retrospective analysis we compared the results of positron emission tomography (PET) using F-18 fluorodeoxyglucose with those of mediastinoscopy in nodal staging for suspected bronchogenic carcinoma. METHODS: From March 1997 to June 2001, 102 patients (86 male,16 female, age 62 +/- 9 years) underwent both PET and mediastinoscopy for radiologically suspected mediastinal lymph node disease in bronchogenic carcinoma. Total body emission scans were acquired 90 to 150 minutes after injection of 230 MBq of F-18 fluorodeoxyglucose. Mediastinoscopic evaluation of lymph node stations was performed according to the method of Mountain and Dresler (1R, 1L, 2L, 2R, 4L, 4R,7). Patients were eligible if surgical staging was performed within 6 weeks after the PET scan. RESULTS. Of the 102 patients, benign lesions were diagnosed in 15. In 87 patients malignant disease was proven by histology, and bronchogenic carcinoma was found in 82. Of 469 nodal stations analyzed, malignancy was documented by histology in 84. In PET analysis 79 true-positive and 304 true-negative samples were found. Five lymph node stations were false negative, and 81 samples were false positive. False-positive findings in PET frequently were seen in inflammatory lung disease. The sensitivity of PET was 94.1%, specificity was 79% with a diagnostic accuracy of 81.6%. The positive predictive value of PET was 49.3%, and the negative predictive value was 98.4%. CONCLUSIONS: In patients with positive PET scan results histologic verification appears necessary for exact lymph node staging. In view of the negative predictive value mediastinoscopy can be omitted in patients with bronchogenic carcinoma whose PET scan results were negative.     

The value of mediastinal staging with endobronchial ultrasound-guided transbronchial needle aspiration in patients with lung cancer

Objective: To evaluate the diagnostic yield, the learning curve and the safety of endobronchial ultrasound-guided transbronchial needle biopsy (EBUS-TBNA) in mediastinal staging of patients with lung cancer. Methods: Mediastinal staging was performed with EBUS-TBNA according to the Danish national guidelines in patients fulfilling one or more of the following criteria: (1) central tumour; (2) enlarged (>10 mm) mediastinal lymph nodes on computed tomography; or (3) positron emission tomography (PET)-positive mediastinal lymph nodes. The study period began in January 2006 when EBUS-TBNA was introduced in the department and ended in December 2007. All records were reviewed retrospectively. None of the four examiners had any previous experience with EBUS-TBNA or ultrasound when the study began. All examinations were performed under general anaesthesia. Patients without useful cytological material from the EBUS-TBNA were subjected to a supplementary standard cervical mediastinoscopy if the mediastinal lymph nodes were found to be enlarged (>10 mm), PET positive or if the examiner was insecure of the result of the EBUS-TBNA. Patients with mediastinal lymph node involvement, detected by EBUS-TBNA or standard cervical mediastinoscopy, were referred to oncological treatment, while those without mediastinal lymph node involvement underwent – if they were otherwise eligible for surgery – resection and systematic lymph node sampling either by thoracotomy or by video-assisted thoracoscopy. Final mediastinal staging was defined as positive if mediastinal lymph node involvement was detected by EBUS-TBNA, standard cervical mediastinoscopy or surgery, or defined as negative otherwise. Results: A total of 157 patients were included in the study. N2/N3 disease was found in 67 patients (42.6%). EBUS-TBNA missed the mediastinal spread in 10 patients. Five of the ten patients had lymph node metastases in station 5, 6 or 8 – out of reach of EBUS-TBNA or standard cervical mediastinoscopy. EBUS-TBNA had a sensitivity of 0.85 (0.74–0.93) and a negative predictive value of 0.90 (0.82–0.95). No complications occurred from EBUS-TBNA. The number of supplementary standard cervical mediastinoscopies decreased significantly in the study period. Conclusion: The results of this study suggest that staging of the mediastinum with EBUS-TBNA is safe and easy to learn – even without previous experience with ultrasound. The diagnostic yield of EBUS-TBNA is in accordance with the yield of standard cervical mediastinoscopy reported in the literature. We do not find any indications in the present study of the recommended necessity for mediastinoscopy in all EBUS-TBNA-negative patients.     

Computed tomography and the TNM classification of lung cancer

Computed tomography (CT) of the thorax and upper abdomen was prospectively evaluated in 84 patients with potentially operable lung cancer. Invasion into the thoracic wall and the mediastinal structures was not accurately demonstrated by CT. For metastatic mediastinal lymph nodes, the sensitivity and specificity of CT were, respectively, 86% and 61% and the positive and negative predictive indices 49% and 91%. For T1, T2 and T3 tumours the negative indices were 100%, 96% and 71%. Positive predictive index did not differ between squamous cell carcinoma and adenocarcinoma. Adrenal metastases were CT-suspected in 17 cases and liver metastases in eight, but were verified by ultrasonography in only one and four cases. CT should be used in preoperative investigation of lung cancer, irrespective of stage. Demonstration of thoracic-wall or mediastinal invasion need not exclude tumour resection. Preoperative mediastinoscopy is indicated if CT shows nodal metastases or if there are signs of tumour invasion, but not in CT-negative T1 or T2 tumour. Abdominal metastases indicated by CT should be investigated with CT-guided needle biopsy.     

支气管内超声引导针吸活检术在纵隔淋巴结CT阳性肺癌分期中的价值

目的 评价支气管内超声引导下针吸活检术(EBUS-TBNA)在纵隔淋巴结CT阳性肺癌病例分期中的应用价值.方法 2009年9月至12月共对28例胸部CT纵隔淋巴结阳性(短径≥1 cm)的肺癌病人行EBUS-TBNA检查.总结穿刺结果,评价该方法的诊断价值和安全性.结果 28例共穿刺淋巴结40组,淋巴结穿刺取材满意率96.3%(27/28例),无任何相关并发症.EBUS-TBNA阳性(取得恶性细胞病理学证据)20例,阴性(未取得恶性细胞病理学证据)8例;阴性者接受进一步外科手术,术后证实纵隔淋巴结转移2例(EBUS-TBNA假阴性).EBUS-TBNA检查准确率92.9%(26/28例),灵敏度90.9%(20/22例),特异度100%(6/6例),阳性预测值100%(20/20例),阴性预测值75%(6/8例).结论 EBUS-TBNA是评价纵隔淋巴结CT阳性肺癌分期的安全有效方法.     

Computed tomography. An effective technique for mediastinal staging in lung cancer

Computed tomographic scans of the chest were utilized to stage mediastinal disease in 148 instances of bronchogenic carcinoma considered for resection in 146 patients. Nodes greater than or equal to 1.5 cm in diameter were interpreted as abnormal. All nodes positive by computed tomography were evaluated by mediastinoscopy, anterior mediastinotomy, or thoracotomy. All patients with negative computed tomographic findings underwent thoracotomy without prior surgical staging. Patients undergoing thoracotomy were divided into two groups. In Group I (first 51 instances) routine mediastinal exploration was not carried out; in Group II (last 97 instances) the mediastinum was explored in every patient and nodes were submitted for histopathological study. The computed tomographic and pathological findings on the mediastinal lymph nodes were compared. The sensitivity, specificity, and accuracy of computed tomography in Group I were 88%, 94%, and 92%, respectively, in Group II 75%, 89%, and 86%, and in the combined group, 80%, 91%, and 88%. The positive predictive index in Group I, Group II, and in the combined group was 88%, 69%, and 77%, respectively. It was lower for central than peripheral lesions (74% versus 88%) and was lowest for lesions in the right upper and left lower lobes. The negative predictive index was greater than 90% for all groups and all tumor sites except the left upper lobe, where it was 89%. Ten patients had false-positive scans, three with old mediastinitis and seven with postobstructive pneumonia; nine of the 10 had central lesions, and seven of these lesions were located in the right upper lobe. Eight patients had false-negative scans; six had para-aortic, subaortic, or postsubcarinal nodes. These nodes would not have been accessible to mediastinoscopy. In only one patient with false-negative nodes would routine mediastinoscopy have prevented thoracotomy and resection. Computed tomographic staging of mediastinal disease is indicated for all patients with lung cancer in whom operation is contemplated. Computed tomography directs the most appropriate staging procedure for patients with positive findings and obviates invasive staging for patients with negative findings.     

Computed tomography for evaluation of mediastinal lymph nodes in lung cancer: correlation with surgical staging

Computed tomography (CT) of the chest (late model) was done preoperatively in 56 candidates for resection of lung cancer. Precise borders for each node region were defined by the American Thoracic Society modification of the classification of the American Joint Committee for Cancer Staging and were used to "map" nodes seen on CT and nodes removed surgically. Metastatic involvement of mediastinal nodes was proven by mediastinoscopy in 11 patients; nodes were removed from multiple regions at thoracotomy in 45 patients. The mediastinum was clearly delineated by CT in 46 patients with determinate scans and was judged normal in 32 (CT-negative scans) and abnormal in 14 (CT-positive scans). A node was considered metastatically involved if it measured greater than 1.5 cm in diameter. Positive nodes were found at surgical staging in 3 of 32 patients with CT-negative scans and in all patients with CT-positive scans. Thus, for the 46 patients with determinate scans, sensitivity was 82%, specificity was 100%, and accuracy (true positive and true negative) was 93%. The high accuracy of CT in these patients suggests that mediastinoscopy is not necessary before thoracotomy in the patient with a CT-negative scan, but that for the patient with a CT-positive or CT-indeterminate scan, the indications for mediastinoscopy remain the same.     

Can FDG-PET reduce the need for mediastinoscopy in potentially resectable nonsmall cell lung cancer?

BACKGROUND: Few fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) nonsmall cell lung cancer (NSCLC) trials have had sufficient patients to adequately evaluate PET for mediastinal staging. We question whether once PET is performed, is mediastinoscopy necessary? METHODS: We performed a 5-year retrospective analysis of operable patients with known or suspicious NSCLC. Standard PET techniques were used. Inclusion criteria were (1) surgical mediastinal nodal sampling by mediastinoscopy within 31 days of the PET and (2) definitive diagnosis. RESULTS: There were 237 patients who met the evaluation criteria; ninety-nine patients with NSCLC and 138 with suspicious lesions (137 men and 100 women; aged 20 to 88 years). The PETs were performed from 0 to 29 days before mediastinoscopy (median, 7 days). The standardized uptake value for the primary lesion was 0 to 24.6 (7.9+/-5.0). Nine primary lesions had no FDG uptake (1 benign, 8 NSCLCs). Seventy-one patients (31%) had mediastinal PET positive disease, and 44 patients (19%) had histologic positive mediastinal disease; N2 41 patients (17%) and N3 9 patients (4%). In 6 patients (3%), the initial frozen sections were negative, but PET positivity encouraged further biopsies that were positive for cancer. The PET sensitivity was 82%, specificity 82%, accuracy 82%, negative predictive value 95%, and positive predictive value was 51%. All primary lesions with a standardized uptake value less than 2.5 and a negative mediastinal PET were negative histologically (n = 29). Logistic regression analysis resulted in 100% specificity for PET in this group. CONCLUSIONS: In NSCLC PET may reduce the necessity for mediastinoscopy when the primary lesion standardized uptake value is less than 2.5 and the mediastinum is PET negative. Accepting this approach in our patient population, the need for mediastinoscopy would have been reduced by 12%.     

The role of FDG-PET scan in staging patients with nonsmall cell carcinoma

BACKGROUND: To assess the role of flourodeoxyglucose-positron-emission tomography (FDG-PET) scan in staging patients with nonsmall cell lung cancer (NSCLC). METHODS: We prospectively studied 400 patients with NSCLC. Each patient underwent a computed tomography (CT) scan of the chest and upper abdomen, other conventional staging studies and had a FDG-PET scan within 1 month before surgery. All suspicious N2 lymph nodes by either chest CT or by FDG-PET scan were biopsied. Patients that were N2 and M1 negative underwent pulmonary resection and complete thoracic lymphadenectomy. RESULTS: The FDG-PET had a higher sensitivity (71% vs 43%, p < 0.001), positive predictive value (44% vs 31%, p < 0.001), negative predictive value (91% vs 84%, p = 0.006), and accuracy (76% vs 68%, p = 0.037) than CT scan for N2 lymph nodes. Similarly, FDG-PET had a higher sensitivity (67% vs 41%, p < 0.001), but lower specificity (78% vs 88%, p = 0.009) than CT scan for N1 lymph nodes. FDG-PET led to unnecessary mediastinoscopy in 38 patients. FDG-PET was most commonly falsely negative in the subcarinal (#7) station and the aortopulmonary window lymph node (#5, #6) stations. It accurately upstaged 28 patients (7%) with unsuspected metastasis and it accurately downstaged 23 patients (6%). CONCLUSIONS:The FDG-PET scan allows for improved patient selection. It more accurately stages the mediastinum, however there are many false positives lymph nodes and it may be more likely to miss N2 disease in the #5, #6, and #7 stations. A positive FDG-PET scan means a tissue biopsy is indicated in that location.     

Results of radical treatment of stage IIIa non-small-cell carcinoma of the lung

From 1979 to 1987, 907 patients with non-oat cell carcinoma of the lung were subjected to thoracotomy: of these, 685 (75.5%) underwent radical resection of the lung tumour. The 230 stage IIIa patients were studied in this paper. These were divided into three groups. First group: 93 patients with only local parietal or mediastinal spread without involvement of the mediastinal lymph nodes (T3N0-1M0); the 5-year survival of this group was 35% (44.1% when the ribs and muscles were not affected). A second group of 118 patients had tumour spreading to the mediastinal lymph nodes, but without local involvement (T1-2N2M0): this group had a 5-year survival of 22.3%. The 5-year survival was better in patients without metastases in the subcarinal lymph nodes than in patients with them (23.76% versus 12.89%). Skipping of lymphatic levels was frequent: 37% of patients with metastasis to mediastinal lymph nodes did not have metastases in the lymph nodes of the lung; 10% of tumours removed by lobectomy had metastases in the lymph nodes of the residual lobe. The third group with parietal and lymphatic mediastinal invasion (T3N2M0) had a poor survival (13.5% at 5 years). The author concludes that it is possible to achieve an acceptable 5-year survival in selected cases with metastasis to mediastinal lymph nodes: when the CT scan demonstrated mediastinal lymph nodes larger than 1.5 cm, mediastinoscopy was carried out and, if positive, the patient was judged inoperable.