Invasive staging of non-small cell lung cancer--a prospective study

Mediastinal lymph node staging for lung cancer

Mediastinal lymph node staging is crucial in deciding the treatment strategy for lung carcinoma. The diagnosis rate of computed tomography is not high; however, it is a standard examination. Although the contrast computed tomography is necessary for an accurate diagnosis, images from the positron emission tomography are excellent, and these two technologies are independent and complementary. Positron emission tomography has a disadvantage of false positives and false negatives, but it should also be used in cases where lymph node diameters are 1 cm or more. However, image-based diagnostic methods are not an alternative to histological examination. The results of a transbronchial needle biopsy are extremely dependent on the inspection method, the diagnostic ability of the physician, and the staging of the case. The transesophageal ultrasound endoscope is useful for reaching parts inaccessible by a mediastinoscope. Although its employment requires technical training, it is becoming popular as a minimally invasive method of obtaining cell and the tissue samples. A thoracoscopic biopsy is considered as a last resort for mediastinal lymph node diagnosis. Carefully-chosen invasive procedures are necessary to diagnose swollen lymph nodes. Although mediastinoscopy is still considered as the gold standard, most procedures will be replaced by a comparatively minimally invasive method in the future.

Bronchoscopy with endobronchial ultrasound guided transbronchial needle aspiration vs. transthoracic needle aspiration in lung cancer diagnosis and staging

BACKGROUND

In evaluating patients with suspected lung cancer, it is important to not only obtain a tissue diagnosis, but also to obtain enough tissue for both histologic and molecular analysis in order to appropriately stage the patient with a safe and efficient strategy. The diagnostic approach may often be dependent on local resources and practice patterns rather than current guidelines. We Describe lung cancer staging at two large academic medical centers to identify the impact different procedural approaches have on patient outcomes.

METHODS

We conducted a retrospective cohort study of all patients undergoing a lung cancer diagnostic evaluation at two multidisciplinary centers during a 1-year period. Identifying complication rates and the need for multiple biopsies as our primary outcomes, we developed a multivariate regression model to determine features associated with complications and need for multiple biopsies.

RESULTS

Of 830 patients, 285 patients were diagnosed with lung cancers during the study period. Those staged at the institution without an endobronchial ultrasound (EBUS) program were more likely to require multiple biopsies (OR 3.62, 95% CI: 1.71-7.67, P=0.001) and suffer complications associated with the diagnostic procedure (OR 10.2, 95% CI: 3.08-33.58, P<0.001). Initial staging with transthoracic needle aspiration (TTNA) and conventional bronchoscopy were associated with greater need for subsequent biopsies (OR 8.05 and 14.00, 95% CI: 3.43-18.87 and 5.17-37.86, respectively) and higher complication rates (OR 37.75 and 7.20, 95% CI: 10.33-137.96 and 1.36-37.98, respectively).

CONCLUSIONS

Lung cancer evaluation at centers with a dedicated EBUS program results in fewer biopsies and complications than at multidisciplinary counterparts without an EBUS program.

Staging of lung cancer: the role of noninvasive, minimally invasive and invasive techniques

Accurate staging and restaging of primary tumour and mediastinal nodes in patients with lung cancer is of significant importance. For primary tumours, computed tomography (CT) scans of the chest are recommended. Positron emission tomography (PET) imaging should be used in patients with curative intent treatment to evaluate metastatic disease. Diagnosis of the primary tumour should be performed using bronchoscopy or CT-guided transthoracic needle aspiration. In patients with enlarged mediastinal nodes and no distant metastasis, invasive staging of the mediastinum is required. For suspicious N2 or N3 disease, endoscopic needle techniques, such as endobronchial ultrasound and transbronchial needle aspiration, oesophageal ultrasound and fine needle aspiration, or a combination of both, are preferred to any surgical staging technique. In cases of suspicious nodes and negative results using needle aspiration techniques, invasive surgical staging using mediastinoscopy or video-assisted thoracic surgery should be performed. In central tumours or N1 nodes, preoperative invasive staging is indicated.Restaging after induction therapy remains a controversial topic. Today, neither CT, PET nor PET/CT scans are accurate enough to make final further therapeutic decisions for mediastinal nodal involvement. An invasive technique providing cytohistological information is still recommended.

Methods for staging non-small cell lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

BACKGROUND

Correctly staging lung cancer is important because the treatment options and prognosis differ significantly by stage. Several noninvasive imaging studies and invasive tests are available. Understanding the accuracy, advantages, and disadvantages of the available methods for staging non-small cell lung cancer is critical to decision-making.

METHODS

Test accuracies for the available staging studies were updated from the second iteration of the American College of Chest Physicians Lung Cancer Guidelines. Systematic searches of the MEDLINE database were performed up to June 2012 with the inclusion of selected meta-analyses, practice guidelines, and reviews. Study designs and results are summarized in evidence tables.

RESULTS

The sensitivity and specificity of CT scanning for identifying mediastinal lymph node metastasis were approximately 55% and 81%, respectively, confirming that CT scanning has limited ability either to rule in or exclude mediastinal metastasis. For PET scanning, estimates of sensitivity and specificity for identifying mediastinal metastasis were approximately 77% and 86%, respectively. These findings demonstrate that PET scanning is more accurate than CT scanning, but tissue biopsy is still required to confirm PET scan findings. The needle techniques endobronchial ultrasound-needle aspiration, endoscopic ultrasound-needle aspiration, and combined endobronchial ultrasound/endoscopic ultrasound-needle aspiration have sensitivities of approximately 89%, 89%, and 91%, respectively. In direct comparison with surgical staging, needle techniques have emerged as the best first diagnostic tools to obtain tissue. Based on randomized controlled trials, PET or PET-CT scanning is recommended for staging and to detect unsuspected metastatic disease and avoid noncurative resections.

CONCLUSIONS

Since the last iteration of the staging guidelines, PET scanning has assumed a more prominent role both in its use prior to surgery and when evaluating for metastatic disease. Minimally invasive needle techniques to stage the mediastinum have become increasingly accepted and are the tests of first choice to confirm mediastinal disease in accessible lymph node stations. If negative, these needle techniques should be followed by surgical biopsy. All abnormal scans should be confirmed by tissue biopsy (by whatever method is available) to ensure accurate staging. Evidence suggests that more complete staging improves patient outcomes.

Meta-analysis study of lymph node staging by 18 F-FDG PET/CT scan in non-small cell lung cancer: comparison of TB and non-TB endemic regions

Lymph node staging in non-small cell lung cancer (NSCLC) is challenging and important for deciding treatment policy. The role of PET/CT scans in lymph node staging of NSCLC remains controversial when comparing TB and non-TB endemic regions. This study systematically reviews the literature regarding the diagnostic performance of PET/CT in lymph node staging of patients with NSCLC, and determines its pooled sensitivity and specificity.

METHODS

The databases of PubMed, Medline, and Cochrane library were searched for relevant studies. Two reviewers independently assessed the methodological quality of each study. A meta-analysis of the reported sensitivity and specificity of each study was performed.

RESULTS

Seven of 86 studies were included. These studies had moderate to good methodological quality. Pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio for patient-based analyses (five studies) were 66%, 92.7%, 5.86%, and 0.41%, respectively, and those for lesion-based analyses (six studies) were 59.4%, 96.5%, 9.37%, and 0.31%, respectively. Subanalysis of endemic regions of tuberculosis (TB) showed that these regions had lower sensitivity and similar specificity to non-TB endemic regions.

CONCLUSION

PET/CT showed high specificity in the lymph node staging of NSCLC and lower sensitivity in TB endemic regions.

Induction therapy for lung cancer: sailing across the pillars of Hercules

In spite of numerous clinical trials, the jury is still out on the value of induction therapy for locally advanced lung cancer. We elected to address this topic from the multifaceted views of the clinicians often involved in lung cancer management and according the most recent views on locally advanced NSCLC. The concept of a prognostic stratification of N2 disease subsets, especially single vs multiple zone, has been introduced and this may lead to a new interpretation of locally advanced NSCLC. Ten crucial issues were identified that may have an impact on the approach to patients with locally advanced lung cancer in everyday practice.

[Utility of PET/CT for mediastinal staging of non-small cell lung cancer in stage III (N2)]

PURPOSE

To evaluate the accuracy of integrated positron emission tomography with (18)F-fluoro-2-deoxy-D-glucose (FDG) and computed tomography (PET/CT) in mediastinal lymph node staging in patients with potentially operable (N2) non-small cell lung cancer (NSCLC) and to ascertain the role of invasive staging in verifying positron emission tomography (PET)/computed tomography (CT) results.

MATERIAL AND METHODS

A retrospective study of consecutive patients with pathologically-proven NSCLC and N2 staging by enhanced CT was performed. A PET/CT scan was performed for all the patients. Lymph node staging was pathologically confirmed when it was possible or by consensus in the Thoracic Cancer Committee. Sensitivity, specificity, negative predictive value and positive predictive value of PET/CT in N2 cases were determined.

RESULTS

A total of 34 patients with N2 by CT were evaluated. PET/CT showed N2 in 30 patients. Discrepancies were found in four patients, two patients were classified as N1 in PET/CT and two patients as N0. Lymph node staging was pathologically confirmed in 20 patients. No false positives were found in PET/CT study. Sensitivity was 94.7%, specificity and positive predictive values were 100% and negative predictive value was 50%.

CONCLUSIONS

Our data show that integrated PET/CT provides high sensitivity and positive predictive value in mediastinal nodal staging of NSCLC patients. Therefore, in patients with potentially resectable lung cancer, neoadjuvant chemotherapy candidate, mediastinoscopy could be reserved for restaging after induction therapy.

Minimally invasive staging of N2 disease: endobronchial ultrasound/transesophageal endoscopic ultrasound, mediastinoscopy, and thoracoscopy

In 2005 the American College of Surgeons conducted a survey examining lung cancer practice patterns at 729 hospitals in the United States. In 11,668 surgically treated patients, 92% received a preoperative chest CT. Only 27% of these patients underwent mediastinoscopy, and lymph node material was sampled in less than half of these patients. At the time of surgical resection, additional mediastinal lymph nodes were sampled in only 58% of patients. In the remaining 42% only the lymph node material attached to the surgical specimen (N1 nodes) was sampled. Although this article discusses the finer points of the minimally invasive evaluation of the N2 lymph nodes, any procedure to evaluate these nodes is better than simply ignoring them.

Invasive mediastinal staging of lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition)

BACKGROUND

The treatment of non-small cell lung cancer (NSCLC) is determined by accurate definition of the stage. If there are no distant metastases, the status of the mediastinal lymph nodes is critical. Although imaging studies can provide some guidance, in many situations invasive staging is necessary. Many different complementary techniques are available.

METHODS

The current guidelines and medical literature that are applicable to this issue were identified by computerized search and were evaluated using standardized methods. Recommendations were framed using the approach described by the Health and Science Policy Committee of the American College of Chest Physicians.

RESULTS

Performance characteristics of invasive staging interventions are defined. However, a direct comparison of these results is not warranted because the patients selected for these procedures have been different. It is crucial to define patient groups, and to define the need for an invasive test and selection of the best test based on this.

CONCLUSIONS

In patients with extensive mediastinal infiltration, invasive staging is not needed. In patients with discrete node enlargement, staging by CT or positron emission tomography (PET) scanning is not sufficiently accurate. The sensitivity of various techniques is similar in this setting, although the false-negative (FN) rate of needle techniques is higher than that for mediastinoscopy. In patients with a stage II or a central tumor, invasive staging of the mediastinal nodes is necessary. Mediastinoscopy is generally preferable because of the higher FN rates of needle techniques in the setting of normal-sized lymph nodes. Patients with a peripheral clinical stage I NSCLC do not usually need invasive confirmation of mediastinal nodes unless a PET scan finding is positive in the nodes. The staging of patients with left upper lobe tumors should include an assessment of the aortopulmonary window lymph nodes.

Noninvasive staging of non-small cell lung cancer: ACCP evidenced-based clinical practice guidelines (2nd edition)

BACKGROUND

Correctly staging lung cancer is important because the treatment options and the prognosis differ significantly by stage. Several noninvasive imaging studies including chest CT scanning and positron emission tomography (PET) scanning are available. Understanding the test characteristics of these noninvasive staging studies is critical to decision making.

METHODS

Test characteristics for the noninvasive staging studies were updated from the first iteration of the lung cancer guidelines using systematic searches of the MEDLINE, HealthStar, and Cochrane Library databases up to May 2006, including selected metaanalyses, practice guidelines, and reviews. Study designs and results are summarized in evidence tables.

RESULTS

The pooled sensitivity and specificity of CT scanning for identifying mediastinal lymph node metastasis were 51% (95% confidence interval [CI], 47 to 54%) and 85% (95% CI, 84 to 88%), respectively, confirming that CT scanning has limited ability either to rule in or exclude mediastinal metastasis. For PET scanning, the pooled estimates of sensitivity and specificity for identifying mediastinal metastasis were 74% (95% CI, 69 to 79%) and 85% (95% CI, 82 to 88%), respectively. These findings demonstrate that PET scanning is more accurate than CT scanning. If the clinical evaluation in search of metastatic disease is negative, the likelihood of finding metastasis is low.

CONCLUSIONS

CT scanning of the chest is useful in providing anatomic detail, but the accuracy of chest CT scanning in differentiating benign from malignant lymph nodes in the mediastinum is poor. PET scanning has much better sensitivity and specificity than chest CT scanning for staging lung cancer in the mediastinum, and distant metastatic disease can be detected by PET scanning. With either test, abnormal findings must be confirmed by tissue biopsy to ensure accurate staging.

Histological diagnosis of mediastinal lymph node metastases from renal cell carcinoma by endobronchial ultrasound-guided transbronchial needle aspiration

Evaluation of mediastinal lymphadenopathy in patients with an intrathoracic nodule post malignancy is crucial for the determination of further treatment. Different radiological modalities are available for the detection of mediastinal lymph node metastases such as multidetector helical CT, PET-scan and PET-CT. However, tissue sampling is required for a firm diagnosis. A minimally invasive method of tissue sampling of mediastinal and hilar lymph nodes using direct real-time endobronchial ultrasound-guided transbronchial needle aspiration has been reported. This method is appropriate not only for cytodiagnosis but also for histological diagnosis. This current study reports a case of mediastinal lymph node metastases from renal cell carcinoma successfully diagnosed histologically by endobronchial ultrasound-guided transbronchial needle aspiration.

Histological diagnosis of spinal chondrosarcoma by endobronchial ultrasound-guided transbronchial needle aspiration

Rare neoplastic diseases including sarcomas can occur in the middle mediastinum. Obtaining a histological specimen is crucial for diagnosis and for establishing a treatment plan. Our research group has recently reported a minimal invasive method of tissue sampling of the mediastinum using direct real-time endobronchial ultrasound-guided transbronchial needle aspiration. By the use of this new modality, histological cores can be obtained for pathological diagnosis that can be used for immunohistochemistry as well as genetic analysis. A very rare case of spinal chondrosarcoma due to hereditary multiple exostoses successfully diagnosed by endobronchial ultrasound-guided transbronchial needle aspiration and by immunohistochemistry with genetic analysis is reported.

Current state of imaging for lung cancer staging

Proper selection and interpretation of imaging studies is essential to provide optimal treatment to patients who have lung cancer. The following combines the recommendations of the American College of Chest Physicians [74] and the authors' current clinical practice guidelines: --All patients who have known or suspected lung cancer should undergo a CT of the chest and upper abdomen. --An FDG-PET study should be performed, if available. --Mediastinoscopy should be performed in all patients except those who have peripheral small (<2 cm) tumors and no evidence of N2 disease on CT or PET imaging. --MRI should be performed for tumors of the superior sulcus to define the relationship of the tumor to adjacent neurovascular structures. --Patients who have neurologic signs or symptoms should undergo a brain imaging study (CT or MRI). --Screening for extrathoracic disease is not necessary in asymptomatic patients who have clinical stage I or II disease.