Combined transbronchial needle aspiration and positron emission tomography for mediastinal staging of NSCLC

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.

Endobronchial ultrasound-guided transbronchial needle aspiration in lung cancer diagnosis and staging

Lung cancer is one of the most prevalent types of cancer in the world. A complete diagnosis of lung cancer involves tissue acquisition for pathological subtype, molecular diagnosis and accurate staging of the disease to guide appropriate therapy. Real-time endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is minimally invasive and relatively safe procedure, which can be done on an outpatient basis under moderate sedation. EBUS-TBNA has been shown to be a safe modality to obtain tissue for diagnosis, staging and molecular profiling in lung cancer. EBUS-TBNA stands out in comparison with other modalities for tissue acquisition in lung cancer. EBUS-TBNA performed with the patient under moderate sedation yields sufficient tissue for sequential molecular analysis in most patients. In this review, we describe the role of EBUS-TBNA in various aspects of diagnosis and staging of lung cancer in the present era along with its future aspects.

Combined transbronchial needle aspiration and (99m)Tc-2-methoxy-isobutyl-isonitrile single photon emission computed tomography for diagnosing enlarged mediastinal lymph nodes

BACKGROUND

To demonstrate the diagnostic accuracy of an integrated approach of blind trans-bronchial needle aspiration (TBNA) and (99m)Tc-2-methoxy-isobutyl-isonitrile single photon emission computed tomography ((99m)Tc-MIBI-SPECT) in diagnosing mediastinal lymph adenopathy.

METHODS

Sixty one consecutive patients with mediastinal lymph adenopathy undergoing both TBNA and (99m)Tc-MIBI-SPECT were prospectively enrolled. Mediastinoscopy was attended in case of negative TBNA.

RESULTS

Eighty three adenopathies were sampled (73 malignant and 10 benign). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of TBNA was 74%, 100%, 100%, and 34%, respectively; and of (99m)Tc-MIBI-SPECT was 96%, 80%, 97%, and 73%, respectively. Combining TBNA and (99m)Tc-MIBI-SPECT results sensitivity, specificity, PPV, NPV of 97%, 100%, 100%, and 83%, respectively, was obtained. TBNA alone avoided medistianoscopy in 65% of cases, while an integrated approach could have potentially obviated mediastinoscopy in 76%.

CONCLUSIONS

(99m)Tc-MIBI-SPECT improved the sensitivity and the NPV of TBNA, reducing the need of mediastinoscopy.

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.

Representativeness of nodal sampling with endobronchial ultrasonography in non-small-cell lung cancer staging

The objective of our study was to determine the procedure-related requirements of mediastinal node sampling with endobronchial ultrasonography with real-time transbronchial needle aspiration (EBUS-TBNA) that would provide negative predictive value (NPV) for the identification of stage III disease in non-small-cell lung cancer (NSCLC) high enough to consider the technique equivalent to cervical mediastinoscopy. Representative EBUS-TBNA was defined as a sampling procedure obtaining satisfactory samples from normal nodes in regions 4R, 4L and 7 or diagnosing malignancy in mediastinal nodes. NPV was estimated using the results of postsurgical staging in patients who underwent surgery as a reference. Two-hundred ninety-six patients staged with EBUS-TBNA were included. Representative samples from regions 4R, 4L and 7 showing nonmalignant cytology were obtained from 98 patients (33.1%) and EBUS-TBNA detected N2/N3 disease in 150 (50.7%). Accordingly, an EBUS-TBNA procedure accomplishing the representativeness criteria required for sampling was attained in 248 of the participating patients (83.8%). The NPV of the procedure in this setting was 93.6%, with false-negative results only found in 5 patients, four of them with nodal metastasis out of the reach of EBUS-TBNA (regions 5, 8 and 9). In conclusion, representative sampling of regions 4R, 4L and 7 is achieved in more than 80% of patients staged using EBUS-TBNA, and in the procedures that attain this requirement a NPV >90% for mediastinal malignancy is reached, a figure equivalent to cervical mediastinoscopy.

Additional value of FDG-PET to contrast enhanced-computed tomography (CT) for the diagnosis of mediastinal lymph node metastasis in non-small cell lung cancer: a Japanese multicenter clinical study

OBJECTIVE

This study was a controlled multicenter clinical study to verify the diagnostic effects of additional FDG-PET to contrast-enhanced CT for mediastinal lymph node metastasis in patients with operable non-small cell lung cancer (NSCLC).

METHODS

NSCLC patients with enlarged mediastinal lymph nodes (short diameter, 7-20 mm), confirmed using contrast-enhanced CT, were examined using FDG-PET to detect metastases prior to surgery. The primary endpoint was the accuracy for concomitantly used CT and FDG-PET showing the additional effects of FDG, compared with CT alone. The secondary endpoints were the clinical impact of FDG-PET on therapeutic decisions and adverse reaction from FDG administration. The images were interpreted by investigators at each institution. Moreover, blinded readings were performed by an image interpretation committee independent of the institutions. The gold standard was the pathological diagnosis determined by surgery or biopsy after PET, and patients in whom a pathological diagnosis was not obtained were excluded from the analysis.

RESULTS

Among 99 subjects, the results for 81 subjects eligible for analysis showed that the accuracy improved from 69.1% (56/81) for CT alone to 75.3% (61/81) for CT + PET (p = 0.404). These findings contributed to treatment decisions in 63.0% (51/81) of the cases, mainly with regard to the selection of the operative procedure. The results of the image interpretation committee showed that the accuracy improved from 64.2% (52/81) (95% CI 52.8-74.6) for CT to 75.3% (61/81) (95% CI 64.5-84.2) for CT + PET. The accuracy for 106 mediastinal lymph nodes improved significantly from 62.3% (66/106) (95% CI 52.3-71.5) for CT to 79.2% (84/106) (95% CI 70.3-86.5) for CT + PET (p < 0.05). We found that no serious adverse drug reactions appeared in any of the 99 patients who received FDG, except for transient mild outliers in the laboratory data for two patients.

CONCLUSIONS

The addition of FDG-PET to contrast-enhanced CT imaging for the staging of NSCLC improved the diagnostic accuracy for mediastinal lymph node metastasis. FDG-PET improved the precision of the staging of NSCLC and contributed to the surgical decisions.

[What is the role of FDG-PET in thoracic oncology in 2010?]

18F-Fluorodeoxyglucose-Positron Emission Tomography (FGD-PET) has been considered to have a major impact on the management of lung malignancies since the beginning of this century. Its value has been demonstrated by many publications, meta-analysis and European/American/Japanese recommendations. PET combined with computed tomography has provided useful information regarding the diagnosis and staging of lung cancer and allows for the delivery of adaptive radiotherapy. In its more common uses, PET has been shown to be cost-effective. With the widespread use of new radiotracers, PET will play an increasing role in the evaluation of response to treatment.

Mediastinal staging of NSCLC with endoscopic and endobronchial ultrasound

Mediastinal staging of non-small-cell lung cancer (NSCLC) is of paramount importance. It distinguishes operable from inoperable disease, guides prognosis and allows accurate comparison of outcomes in clinical trials. Noninvasive imaging modalities for mediastinal staging include CT, PET and integrated PET-CT. Mediastinoscopy is considered the current gold standard; however, each of these techniques has limitations in sensitivity or specificity. These inadequacies mean that 10% of operations performed with curative intent in patients with NSCLC are futile, owing to inaccurate locoregional lymph-node staging. Endoscopic and endobronchial ultrasound-guided mediastinal lymph-node aspiration are important and promising innovative techniques with reported sensitivities and specificities higher than standard investigations. The role of these techniques in mediastinal lymph-node staging is evolving rapidly and early data suggest that they may diminish the need for invasive surgical staging of the mediastinum. Furthermore, these are outpatient procedures that do not require general anesthesia and may be combined safely in the same sitting, for optimal accuracy of mediastinal staging. We propose a new algorithm for the diagnosis and staging of NSCLC, based on the current evidence, which incorporates endoscopic and endobronchial ultrasound as a first investigation after CT in patients with intrathoracic disease.

[The advantage of Positron Emission Tomography combined with Computer Tomography (PET-CT) in the diagnosis of lung cancer (experience with 408 patients)]

The authors analyzed the results of PET-CT scans made with oncological indications among 408 patients. One hundred and fifty-four PET-CTs were done to characterize pulmonary foci, after which in 59 cases lung surgery was performed. The method's sensitivity in respect to malignancy was 100%, specificity was 56%. Staging of affected lymph nodes resulted in 17 mediastinoscopies and 54 thoracotomies. In the former indications PET-CT-positive lymph nodes always need cytologic/histologic verification. M-staging done with PET-CT was performed in 141 cases, mediastinal restaging of patients having received neoadjuvant chemotherapy was done in 24 cases. The latter indications we consider superfluous because of the diagnostic inaccuracy of PET-CT. In 175 cases we analyzed the frequently determining factor of the PET-CT scan in the indication of lung surgery. The authors wish to share their experience for the better use of this method and to accelerate the inclusion of PET-CT into the diagnostic protocol.

Utilidad de la ultrasonografía endobronquial con punción-aspiración en tiempo real para la estadificación de la neoplasia broncopulmonar

BACKGROUND AND OBJECTIVE

To determine the usefulness of endobronchial ultrasonography (EBUS) with real-time needle aspiration (NA) for lung cancer staging.

PATIENTS AND METHOD

All patients examined with EBUS and real-time NA to measure and sample mediastinal and lobar nodes for lung cancer staging during one year were included, independently of the size of the mediastinal nodes at computed tomography (CT).

RESULTS

Eighty two nodes > 5 mm were sampled using EBUS-NA (16.0 [7.2] mm; 23 cases <or= 10 mm, 28.0%), from 67 patients were examined for staging (64.0 [12.4] years). NA from 72 nodes was adequate (87.8%) (38 normal node, 46.3%; 31 neoplasia, 37.8%; 3 granuloma, 3.7%), and EBUS-NA found neoplasia in 4/23 nodes <or= 10 mm (17.4%). EBUS-NA showed neoplasic nodes in 5 out of 24 patients with a normal mediastinum at CT (20.8%). The use of EBUS-NA avoided mediastinoscopy in 62 of the 67 patients included in the study (92.5%).

CONCLUSIONS

The use of EBUS with real-time NA on mediastinal and lobar nodes obtain representative pathological samples and allow the avoidance of mediastinoscopy in over 90% of the patients referred for lung cancer staging.

La tomographie par émission de positons au 18fluorodésoxyglucose (18FDG-TEP) dans la prise en charge du cancer bronchique non à petites cellules en 2006

Technological progress and numerous published studies allow to estimate the best place of the 18F-fluorodeoxyglucose positron emission tomography, a real functional metabolic imagery, in the clinical and therapeutic strategy of non small cell lung cancers.