A group of European experts has published a consensus document to better define which stage III lung cancers can be operated on. This work aims to harmonize practices and improve patient selection for future clinical trials. Professor Paul Hofman, Director of IHU RespirERA, contributed to this publication as a co-author.
Better identifying operable stage III lung cancers
Non-small cell lung cancer (NSCLC), the most common type of lung cancer, can be particularly difficult to assess at stage III. At this stage, the disease can vary greatly from one patient to another: the tumor may still be relatively localized, or more advanced, with lymph nodes already involved in the chest.
This variability complicates medical decision-making, especially when determining whether surgery is possible. It also makes it harder to compare clinical trials, as patients included may not meet the same criteria from one center to another.
To address this challenge, a European consensus led by the EORTC has been developed to better define technical resectability (the ability to completely remove the tumor through surgery).
A common framework to better compare clinical trials
The objective of this work is to establish shared criteria for future clinical trials involving stage III lung cancer.
In practice, this means avoiding situations where each team uses its own definition of an “operable” tumor. With clearer and standardized criteria, studies will be more consistent, easier to compare, and ultimately more useful in improving patient care.
A collaborative effort at the European level
This document is the result of a collaboration between several international scientific societies. To build this consensus, experts used a well-established method known as the Delphi process (a structured approach that allows specialists to reach a common agreement through several rounds).
Their work was based on:
- a systematic review of the scientific literature;
- an international survey involving 558 professionals;
- the analysis of 105 real clinical cases.
In total, 36 experts contributed to the development of 34 consensus statements.
A decision that must be made as a team
The document emphasizes that decisions should never be made by a single specialist. Determining whether a tumor is operable requires the input of a multidisciplinary team, including at least a thoracic surgeon, a medical oncologist, a radiation oncologist, a radiologist, a pathologist, and a pulmonologist.
The initial assessment must also be comprehensive. It includes:
- a contrast-enhanced chest CT scan;
- a PET-CT scan (an imaging test used to detect suspicious areas in the body);
- brain imaging, preferably an MRI.
Additional examinations are also recommended to assess whether mediastinal lymph nodes are involved (lymph nodes located between the lungs).
More precise criteria depending on disease extent
The consensus provides guidance across different situations.
Stage IIIA is generally considered operable, particularly in cases where the tumor remains localized and lymph node involvement is limited.
Involvement of so-called N2 lymph nodes plays a key role in decision-making. When a single lymph node station is affected, without large size or invasion of surrounding structures, the tumor is considered resectable. When multiple lymph node stations are involved, the situation becomes more complex and should be assessed on a case-by-case basis.
However, when lymph nodes are very large or invade surrounding tissues, the tumor is generally considered non-operable.
For stage IIIB, surgery may still be considered in selected cases, but only under specific conditions. When lymph node involvement is more extensive, the disease is considered non-resectable.
Stage IIIC is considered non-operable.
The specific case of T4 tumors
The document also provides clarification for T4 tumors, which correspond to more locally advanced disease.
In some cases, surgery may still be an option, for example when the tumor is classified as T4 due to its size, or when it involves structures that can still be surgically removed.
Conversely, when the tumor invades complex organs or structures such as the heart, esophagus, or trachea, surgery is generally not recommended, except in very specific situations and in highly specialized centers.
Remaining questions and uncertainties
The consensus also highlights areas that remain uncertain. For instance, the exact definition of “bulky” lymph nodes may still vary between teams.
Another important question concerns treatments given before surgery. In some cases, these treatments can shrink the tumor and make surgery possible. The exact role of these strategies still needs to be clarified in the coming years.
Contribution of Professor Paul Hofman
Professor Paul Hofman, Director of IHU RespirERA, contributed to this work as a co-author.
His involvement included the development of the study methodology, as well as the revision and editing of the final manuscript. As a pathology expert, he took part in this collective effort alongside other European specialists, with the aim of better standardizing the evaluation of stage III lung cancers.
This European consensus represents an important step forward in better defining which stage III lung cancers can be operated on. By providing clearer and shared criteria, it is expected to improve the design of future clinical trials and contribute to better patient management.
