Clinical value of video-assisted thoracoscopy for preoperative staging of non-small cell lung cancerA prospective study of 105 patients

GOECP/SEOR radiotheraphy guidelines for non-small-cell lung cancer

Non-small cell lung cancer (NSCLC) is a heterogeneous disease accounting for approximately 85% of all lung cancers. Only 17% of patients are diagnosed at an early stage. Treatment is multidisciplinary and radiotherapy plays a key role in all stages of the disease. More than 50% of patients with NSCLC are treated with radiotherapy (curative-intent or palliative). Technological advances-including highly conformal radiotherapy techniques, new immobilization and respiratory control systems, and precision image verification systems-allow clinicians to individualize treatment to maximize tumor control while minimizing treatment-related toxicity. Novel therapeutic regimens such as moderate hypofractionation and advanced techniques such as stereotactic body radiotherapy (SBRT) have reduced the number of radiotherapy sessions. The integration of SBRT into routine clinical practice has radically altered treatment of early-stage disease. SBRT also plays an increasingly important role in oligometastatic disease. The aim of the present guidelines is to review the role of radiotherapy in the treatment of localized, locally-advanced, and metastatic NSCLC. We review the main radiotherapy techniques and clarify the role of radiotherapy in routine clinical practice. These guidelines are based on the best available evidence. The level and grade of evidence supporting each recommendation is provided.

Controversies in Mediastinal Staging for Nonsmall Cell Lung Cancer

Mediastinal lymph nodal involvement in nonsmall cell lung cancer plays a crucial role in deciding treatment strategy. Survival falls markedly with increasing involvement of mediastinal nodal stations. Hence, accurate staging of the mediastinum with lowest morbidity is of utmost importance. A wide array of invasive and noninvasive modalities that complement each other in assessing the nodes are available at our disposal. Guidelines recommend noninvasive imaging as the initial step in the staging algorithm for all tumors, followed by invasive staging. No single modality has proven to be the ideal method to stage the mediastinum when used alone. In the present decade, minimally invasive endobronchial ultrasound (EBUS) has challenged the position of surgical mediastinoscopy, which has been the gold standard, historically. However, a negative EBUS needs to be confirmed by surgical mediastinoscopy. Video-assisted mediastinoscopic lymphadenectomy has also come to the forefront in last two decades and has shown exceptional results, when performed in experienced centers. This review details the various modalities of mediastinal staging and the controversies surrounding the optimal method of staging, restaging after neoadjuvant therapy, and the most cost-effective strategy.

Mediastinal staging for non-small cell lung cancer

The staging of mediastinal lymph nodes for lung cancer is crucial for planning treatments or reinterventions. In potentially curable patients the aim of mediastinal staging is to exclude the presence of malignancy in mediastinal lymph nodes with a high level of accuracy while also considering clinical factors and the balance of the benefits and risks of tissue sampling techniques. Mediastinal staging is based on computed tomography (CT) and positron emission tomography (PET) and can be sufficient when no mediastinal abnormalities are present and the probability of unforeseen N2 disease is low. In the case of bulky lymph nodes with a high probability of malignancy in PET-CT, tissue confirmation is not normally required. If mediastinal sampling is needed it can be achieved by endosonographic techniques, including endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) or a combination of the two. Positive results do not need further confirmation. In the case of negative results, surgical techniques still play a role in the selected cases discussed by multidisciplinary lung cancer committees. New mediastinal surgical techniques including video-assisted cervical mediastinoscopy (VACM), video-assisted mediastinoscopic lymphadenectomy (VAMLA), and transcervical extended mediastinal lymphadenectomy (TEMLA) have been shown to be useful in selected patients. Final pathological staging is based on lymph node removal during surgery and can be achieved by taking one of two approaches: lymph node sampling or systematic lymph node sampling. The accuracy of PET-CT and mediastinal endosonography is lower for mediastinal restaging than it is for surgical techniques; their false positive and false negative (FN) rate is high and so, they require histological confirmation. Here we explain and revise the results from the most recent studies and current international guidelines.

Mediastinal staging: when and how?

Mediastinal staging for lung cancer includes both the assessment of mediastinal lymph nodes status before treatment and the postoperative pathological staging obtained by lymph-node removal performed during surgery. In patients with early stage NSCLC, the aim is to exclude with the highest certainty and the lowest morbidity the presence of mediastinal node involvement. Before treatment, mediastinal staging is based on imaging techniques, endoscopic techniques, and surgical procedures. Final pathological staging is based on lymph-node removal performed with lung resection according with different modalities (sampling, systematic dissection, etc.) and various approaches (thoracotomy, VATS, robotic). Data and indications from literature evidences are reported and discussed.

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.

Lung cancer staging: a concise update

Diagnosis and clinical staging of lung cancer are fundamental to planning therapy. The techniques for clinical staging, i.e anatomic and metabolic imaging, endoscopies and minimally invasive surgical procedures, should be performed sequentially and with an increasing degree of invasiveness. Intraoperative staging, assessing the magnitude of the primary tumour, the involved structures, and the loco-regional lymphatic spread by means of systematic nodal dissection, is essential in order to achieve a complete resection. In resected tumours, pathological staging, with the systematic study of the resected specimens, is the strongest prognostic indicator and is essential to make further decisions on therapy. In the present decade, the guidelines on lung cancer staging of the American College of Chest Physicians and the European Society of Thoracic Surgeons are based on the best available evidence and are widely followed. Recent advances in the classification of the adenocarcinoma of the lung, with the definition of adenocarcinoma in situ, minimally invasive adenocarcinoma and lepidic predominant adenocarcinoma, and the publication of the eighth edition of the tumour, node and metastasis classification of lung cancer, have to be integrated into the staging process. The present review complements the latest guidelines on lung cancer staging by providing an update of all these issues.

Executive summary of the SEPAR recommendations for the diagnosis and treatment of non-small cell lung cancer

The Thoracic Surgery and Thoracic Oncology groups of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) have backed the publication of a handbook on recommendations for the diagnosis and treatment of non-small cell lung cancer. Due to the high incidence and mortality of this disease, the best scientific evidence must be constantly updated and made available for consultation by healthcare professionals. To draw up these recommendations, we called on a wide-ranging group of experts from the different specialties, who have prepared a comprehensive review, divided into 4 main sections. The first addresses disease prevention and screening, including risk factors, the role of smoking cessation, and screening programs for early diagnosis. The second section analyzes clinical presentation, imaging studies, and surgical risk, including cardiological risk and the evaluation of respiratory function. The third section addresses cytohistological confirmation and staging studies, and scrutinizes the TNM and histological classifications, non-invasive and minimally invasive sampling methods, and surgical techniques for diagnosis and staging. The fourth and final section looks at different therapeutic aspects, such as the role of surgery, chemotherapy, radiation therapy, a multidisciplinary approach according to disease stage, and other specifically targeted treatments, concluding with recommendations on the follow-up of lung cancer patients and surgical and endoscopic palliative interventions in advanced stages.

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.

Joint use of cervical mediastinoscopy and video-assisted thoracoscopy for the evaluation of mediastinal lymph nodes in patients with non-small cell lung cancer

OBJECTIVE

To evaluate the efficacy of the joint use of cervical mediastinoscopy and video-assisted thoracoscopy for the sampling of mediastinal lymph nodes in patients with non-small cell lung cancer (NSCLC) and candidates for pulmonary resection.

METHODS

Sixty-two patients diagnosed with NSCLC were submitted to cervical mediastinoscopy and video-assisted thoracoscopy. The samples obtained (from paratracheal chains, anterior and posterior subcarinal chains, paraesophageal chains and pulmonary ligament) were submitted to frozen section analysis. The following variables were also evaluated: age; gender; weight loss; diagnostic method; tomographic findings; histological type; staging; and location and size of the primary tumor.

RESULTS

In 11 patients, mediastinoscopy showed no involvement of the subcarinal chain, whereas such involvement was identified when video-assisted thoracoscopy was used: positive predictive value = 88.89% (95% CI: 51.75-99.72); negative predictive value = 94.34% (95% CI: 84.34-98.82); prevalence = 17.74% (95% CI: 9.2-29.53); sensitivity = 72.73% (95% CI: 39.03-93.98); and specificity = 98.77% (95% CI: 93.31-99.97). In 60% of the patients with involvement of the posterior subcarinal chain, the primary tumor was in the right inferior lobe. (p = 0.029)

CONCLUSIONS

The joint use of cervical mediastinoscopy and video-assisted thoracoscopy for the evaluation of posterior mediastinal lymph nodes proved to be an efficacious method. When there is no access to posterior chains by means of ultrasound with transbronchial or transesophageal biopsy, which dispenses with general anesthesia, this should be the method of choice for the correct evaluation of mediastinal lymph nodes in patients with NSCLC.

Narrow band imaging (NBI) during medical thoracoscopy: first impressions

Background

This is the first ever evaluation of narrow band imaging (NBI), an innovative endoscopic imaging procedure, for the visualisation of pleural processes.

Methods

The pleural cavity was examined in 26 patients with pleural effusions using both white light and narrow band imaging during thoracoscopy under local anaesthesia.

Results

In the great majority of the patients narrow band imaging depicted the blood vessels more clearly than white light, but failed to reveal any differences in number, shape or size. Only in a single case with pleura thickened by chronic inflammation and metastatic spread of lung cancer did narrow band imaging show vessels that were not detectable under white light.

Conclusion

It is not yet possible to assess to what extent the evidence provided by NBI is superior to that achieved with white light. Further studies are required, particularly in the early stages of pleural processes.

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.

Flexible Videopericardioscopy in cT4 Nonsmall-Cell Lung Cancer With Radiologic Evidence of Proximal Vascular Invasion

BACKGROUND

The purpose of this study was to evaluate feasibility and effectiveness of flexible videopericardioscopy (FVP) in assessing resectability of cT4 nonsmall-cell lung cancer (NSCLC) with radiologic evidence of proximal vascular invasion.

METHODS

Between March 2003 and December 2005, 22 patients with NSCLC deemed unresectable owing to signs of proximal vascular invasion at multislice computed tomography were included in a nonrandomized prospective study entailing FVP performed before curative-intent thoracotomy. Primary outcome measures were technical feasibility (graded from 1 = poor to 3 = excellent) and quality of anatomic visualization (graded as diagnostic or nondiagnostic). Patients with FVP evidence of proximal vascular invasion did not receive thoracotomy and were included in an induction chemoradiotherapy protocol.

RESULTS

Mean operative time was 31 +/- 6 minutes. Technical feasibility ranged from good to excellent in 21 patients. In 1 patient, FVP was not completed owing to intrapericardial adhesions. In 7 patients, FVP disclosed no tumor spread to intrapericardial pulmonary vessels, and radical resection was carried out. The FVP findings were considered not diagnostic because of poor visualization of the right pulmonary artery in 2 patients with bulky hilar tumors. There was no operative mortality and morbidity. Mean hospital stay was 2.9 +/- 1 days for patients who did not undergo thoracotomy and 6.3 +/- 1 days for patients receiving FVP plus resection. Definitive pathologic staging in patients undergoing resection was pT3N1 (n = 2), pT3N0 (n = 2), pT2N0 (n = 3), and pT2N1 (n = 1).

CONCLUSIONS

Flexible videopericardioscopy proved safely feasible and allowed a better assessment of centrally located NSCLC, with radiologic evidence of proximal vascular involvement eventually resulting in increased resectability rate.

The Future in Diagnosis and Staging of Lung Cancer

Surgical techniques remain central to the diagnosis and staging of lung cancer. Clinical situations which invoke the role of surgery include the diagnosis of solitary pulmonary masses, staging of the mediastinum, restaging of the mediastinum and the assessment of resectability. The techniques available include cervical mediastinoscopy, anterior mediastinotomy, video-assisted thoracoscopy and different procedures for intra-operative mediastinal lymph node assessment including systematic nodal dissection, lobe-specific nodal dissection and sentinel node mapping. The staging of lung cancer is continuously evolving as technological advances combine with clinical advances to better stratify patients into treatment and prognostic categories and alter pre-operative investigation algorithms. Although most of the surgical techniques have been around for many years, it is their application in future which is likely to change. The increasing use of positron emission tomography/computed tomography fusion imaging is raising the proportion of patients being shown to have additional lesions that could contraindicate surgical treatment but which require tissue confirmation to exclude a false-positive examination. Many such lesions are amenable to the expanding techniques available to the interventional endoscopist. The relationship between the surgeon and the endoscopist must become closer to ensure that the appropriate technique is used at each point in the patient's pathway. The future of surgical techniques will be driven by: (1) developments in screening and imaging, with a likelihood that more early stage cancers will present and may be amenable to minimally invasive surgical approaches with the possibility of a role for robotics and nanotechnology; (2) improvements in neoadjuvant therapies which will demand flawless mediastinal staging and restaging; (3) advances in molecular biology which, whilst currently requiring that surgery provide samples of tumour and lymph node tissue to fully characterize the disease, do hold the promise that ever smaller amounts of tissue will be required and that eventually the genetic fingerprint will provide a biological ultrastaging to perhaps supersede anatomical staging.

Near infrared thoracoscopy of tumoral protease activity for improved detection of peripheral lung cancer

Improvement in tumor detection using "smart" probes in combination with microcatheter fluorescence thoracoscopy was evaluated in a mouse model. These imaging probes increase in fluorescence intensity after protease activation; cathepsin B is a major activator of the probes used in this study. Lewis lung carcinoma cells were orthotopically implanted in the subpleural lung parenchyma. Two activatable near infrared (NIR) probes with different excitation and emission wavelength were administered intravenously to determine whether wavelength would modulate target to background ratio (TBR). Mice were selectively intubated and thoracoscopy performed. A 0.8 mm outer diameter imaging catheter was used to record simultaneous white-light (anatomic) and NIR (protease expression) images. At both wavelength pairs evaluated (680/700 and 750/780 nm excitation/emission), the intrinsic luminosity differences between tumors and normal lung in uninjected animals was low (p > 0.3 and p = 0.4, respectively and TBR near 1). In mice receiving protease probes IV, tumors were significantly more fluorescent than adjacent lung (p < 0.0005 for 680/700 and p < 0.006 for 750/780) and TBR increased to approximately 9-fold. Confirmatory fluorescence microscopy and immunohistochemistry were similar and revealed that normal lung had very low levels when compared to tumors of cathepsin B and probe fluorescence. In conclusion, protease sensitive imaging probes selective for cathepsin B, imaged with NIR microcatheters, significantly increase the TBR, making small peripheral lung tumors more readily apparent. Such an approach may be a useful adjunct in staging or restaging patients with lung cancer to find minimal disease in the pleural and subpleural space.

Problems in pathologic staging of lung cancer

CONTEXT

Tumor stage is the most important prognostic and predictive factor for patients with lung cancer, the most lethal neoplasm in the United States. It is used by thoracic surgeons, radiation therapists, and oncologists to determine whether patients with these neoplasms will be treated surgically with curative intent or with palliative radiation therapy and/or chemotherapy.

OBJECTIVE

To review the variety of practical problems that can arise during the assessment of the pathologic stage and other prognostic/predictive factors included in the College of American Pathologist checklist for evaluation of resected lung neoplasms.

DATA SOURCES

Potential practical difficulties that can arise during the pathologic staging of lung cancer patients include the distinction between pT1, pT2, and pT3 lesions based on their location and the presence of visceral pleura and/or parietal pleura invasion; the differential diagnosis between multiple synchronous or metachronous primary lung neoplasms (pT1m) and intrapulmonary metastasis of non-small cell carcinoma of the lung (pT4 or pM1 according to their location); and the role of the recent American Joint Committee on Cancer terminology for the classification of lymph nodes (isolated tumor cells, micrometastases, and metastases).

CONCLUSIONS

The variety of practical problems that can arise during the assessment of important prognostic and predictive features such as resection margin status and evaluation of lymphovascular invasion are reviewed. A brief discussion of the assessment of the effects of neoadjuvant therapy on resected lung neoplasms is also included.