Staging and Resectability in NSCLC

The Importance of Pathologic Staging for NSCLC

Pathologic staging can dramatically improve staging accuracy1

The correlation between clinical and pathologic staging is only 50% to 60%.2 In one study using PET-CT alone, mediastinal lymph nodes were3

falsely overstaged in

≈19% of patients

falsely understaged in

≈13% of patients

Clinical and pathologic staging methods
Clinical and pathologic staging methods

*Approximate ranges based on published studies.

NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) recommend clinical and pathologic staging to assess whether N2 nodal disease is present before starting therapy.7

Different pathologic staging methods have specific advantages and considerations2,5,8

Mediastinoscopy and EBUS and EUS pathologic staging
Mediastinoscopy and EBUS and EUS pathologic staging

Pathologic staging methods can access different nodal stations2,8

Pathologic staging for nodal stations
Pathologic staging for nodal stations

Guidelines recommend pathologic staging when the likelihood of mediastinal node positivity is increased2

Even if N2 nodes are negative through CT and PET imaging, guidelines recommend confirming the results with pathologic staging based on certain disease characteristics, including2,4,9:

N1 through clinical staging

30% of patients with N1 disease based on CT scans were upstaged to N2 or N3 after pathologic assessment10


Central tumor

Unforeseen N2 disease was ≈7x more likely in patients with central tumors vs peripheral tumors11


Tumor >3 cm

T2 tumors were ≈3x more likely to have unforeseen N2 metastases than T1 tumors12

Suggested algorithm for pathologic nodal assessment2,4,9,*

 

Pathologic nodal assessment algorithm
Pathologic nodal assessment algorithm

*Some differences in the exact algorithm used exist between institutions.

N1 through clinical staging.

There is increased likelihood of positive mediastinal lymph node involvement when these nodes are CT and PET negative for pure solid tumors >3 cm.12 The rate of occult N2 disease in patients with ground-glass tumors is low.12

§Mainly adenocarcinoma with high FDG uptake.9

Multidisciplinary team collaboration

Guidelines recommend a multidisciplinary approach to determine optimal steps for diagnostic staging, including7,13:

Thoracic radiologists
Thoracic radiologists

Thoracic radiologists

Interventional radiologists
Interventional radiologists

Interventional radiologists

Thoracic surgeons
Thoracic surgeons

Thoracic surgeons

Pulmonologists
Pulmonologists

Pulmonologists

Because N2 involvement affects stage and resectability, pathologic staging is crucial for obtaining the most accurate nodal assessment to inform prognosis and treatment decisions.2,14

ACCP, American College of Chest Physicians; CT, computed tomography; EBUS, endobronchial ultrasound; EUS, endoscopic ultrasound; FDG, fludeoxyglucose; FNA, fine needle aspiration; NCCN, National Comprehensive Cancer Network; NSCLC, non–small cell lung cancer; PET, positron emission tomography; SUV, standardized uptake value; TBNA, transbronchial needle aspiration; VATS, video-assisted thoracoscopic surgery.

References: 1. Steinfort DP et al. Medicine (Baltimore). 2016;95(8):e2488. 2. Heineman DJ et al. Ther Adv Med Oncol. 2017;9(9):599-609. 3. Harders SW et al. Cancer Imaging. 2014;14:23. 4. Silvestri GA et al. Chest. 2013;143(5)(suppl):e211S-e250S. 5. Rami-Porta R et al. Eur Respir J. 2018;51(5). pii: 1800190. 6. Schmidt-Hansen M et al. Cochrane Database Syst Rev. 2014;(11):CD009519. 7. Referenced with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Non–Small Cell Lung Cancer V4.2019. © National Comprehensive Cancer Network, Inc. 2019. All rights reserved. Accessed April 29, 2019. NCCN makes no warranties of any kind whatsoever regarding their content, use or application and disclaims any responsibility for their application or use in any way. To view the most recent and complete version of the guideline, go online to NCCN.org. 8. Yasufuku K et al. Chest. 2006;130:710-718. 9. Postmus PE et al. Ann Oncol. 2017;28(suppl 4):iv1-iv21. 10. Hishida T et al. Thorax. 2008;63:526-531. 11. Lee PC et al. Ann Thorac Surg. 2007;84:177-181. 12. Gao SJ et al. Lung Cancer. 2017;109:36-41. 13. Detterbeck FC et al. Chest. 2013;143(5)(suppl):7S-37S. 14. Amin MB et al. AJCC Cancer Staging Manual. 8th ed. Springer; 2017.