This page contains a Flash digital edition of a book.
Lung Cancer Figure 1: Flowchart for a Mediastinal Study Contrast enhanced CT


adequate samples, namely samples with neoplastic cells or lymphoid cellularity.36


Others have proposed a score based on the number of lymphocytes on the slide; using EBUS-TBNA and accounting only for the samples with more than 40 lymphocytes per field (magnification x40), the authors produced only one false-negative.37


Therefore, we Positive mediastinal nodes PET Negative mediastinal nodes


can suppose that using semi-quantitative criteria for evaluating adequacy can improve TBNA performance on healthy lymph nodes, modifying the value of a negative result in mediastinal staging.


TBNA, USTBNA, EUSFNA


N2 >10%


post-test probability*


N1 N0 Surgical Techniques


Positive STOP


N2 Negative >10%


Mediastinoscopy, thoracoscopy, etc.


*Bayes’ theorem.


CT = computed tomography; EUSFNA = endoscopic ultrasound-guided fine-needle aspiration; PET = positron emission tomography; SUV = standardised uptake value; T = tumour; TBNA = transbronchial needle biopsy; USTBNA = ultrasound-directed transbronchial needle aspiration.


examinations.10–14


However, despite a small amount of reported false-negatives (5–8%), a recent meta-analysis showed that in patients with normal-sized lymph nodes the false-negative rate may reach 25%.15


This happens above all for central5,16,17 or large tumours1,18 Negative


post-test probability*


<10% Surgery <10%


Grading 3* T SUV >10* T size* Central T*


Surgical techniques are considered as a source of reference for the evaluation of suspicious lymph nodes following a negative or inadequate cytological result. Of the surgical techniques, mediastinoscopy is the gold standard in the pre-operative staging of lung cancer. Its sensitivity is high (75–90%) and complications are rare, although potentially severe.5,38–41


paratracheal stations (levels one, two and four) and the subcarinal station (level seven, anterior).5 among surgeons;42


In general, this technique is not popular


in addition, the increasing availability and accuracy of ultrasound-guided minimally invasive techniques have been challenging the reference role of mediastinoscopy in recent years.43


Video-assisted thoracic surgery (VATS) can reach several mediastinal levels, in particular nodal stations five and six, but its sensitivity varies widely among series. The aorto-pulmonary window station five can be approached by Chamberlain’s anterior mediastinotomy when other techniques are not available or have failed.5


or for


tumours with an elevated standardised uptake value (SUV).18,19 Nevertheless, owing to its high performance, PET is considered the reference test for all potentially operable patients.20


Needle Aspiration Techniques


The use of TBNA in lung cancer staging has recently been steadily increasing. The sensitivity and specificity of this technique are around 76 and 98%, respectively.21 coupled with TBNA,22


When rapid on-site examination (ROSE) is the performance of TBNA increases owing to the


shorter duration and lesser risks of the procedure according to some authors,23


or because of better accuracy according to others.24,25


When supported by other complementary techniques, such as EBUS, TBNA yield may improve, and its sensitivity may rise >90% when a convex probe is used, which allows direct observation of the needle piercing the lymph node.26–29


Staging Protocols for Mediastinum It is well known that in clinical stage N0, histology–cytology finds nodal metastases in up to 20–25% of cases.18,44,45


Unexpected


mediastinal involvement (even without CT or PET abnormalities in the mediastinum) is more common if pathological hilar (N1) lymph nodes are present.18,46


Many risk factors for unforeseen mediastinal metastasis have been described,8,18,47–58


including tumour size, adenocarcinoma cell type, elevated levels of carcinoenmryonic antigen (CEA), central or right upper lobe location, tumour-related symptoms, patient age <65 years, tumour SUV >9–10 and pleural involvement. When risk factors are lacking, some authors suggest avoiding systematic lymph node dissection during surgical resection.59,60


However, in clinical practice the worthwhile


application of ultrasound appears limited to lymph nodes at American Thoracic Society (ATS) stations one and two (in such cases endoscopists have no definite safe landmarks for the puncture), to small lymph nodes (≤5mm) and when ROSE is not performed.30,31


Similar to TBNA, EUS-FNA


provides high sensitivity and specificity; its major limitations are lymph nodes anterior to the trachea and to the main bronchi.32–34


As for other needle aspiration techniques, a positive result can be considered definitive for staging, while surgical confirmation is generally required in the event of a negative result.5,35


This assumption


does not consider any qualitative evaluation of a non-diagnostic sample; in fact, to date no reliable criteria for distinguishing whether a sample comes from a lymph node or not have been identified. Martinez-Olondris et al. in a series of 194 patients demonstrated that the sensitivity of TBNA was 88% when the study included only


32


The European Society of Thoracic Surgery (ESTS) recommends direct resort to surgery in cT1N0 tumours only for squamous cell carcinoma, and to mediastinoscopy for other cell types; in the other clinical stages, minimally invasive techniques (EBUS-TBNA, EUS-FNA) and, if negative, mediastinoscopy are suggested. When PET is available, surgery is advised in clinical stage 1, except in central tumours, adenopathies >1.6cm and tumours with a low SUV.1


However,


observations that the probability of mediastinal metastasis rises in line with the tumour SUV value18,19 ACCP5


conflict with the ESTS position. The


guidelines agree on avoiding further examinations in peripheral stage 1 tumours, but do not differentiate among cell types, and suggest cytological sampling irrespective of PET result when CT shows enlarged nodes and surgical confirmation of every negative needle aspirate. This argument is sometimes used due to the moderate negative predictive value of mediastinoscopy, which is not vastly different from that of EBUS-TBNA.61


node involvement seem to benefit from surgery,62–69


As only patients with microscopic many surgeons


EUROPEAN ONCOLOGY & HAEMATOLOGY


However, it can only reach the


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92