In lung cancer, the stage is usually determined using the TNM system. This looks at the tumour, the lymph nodes and any metastases.
But the stage does not tell the whole story. Two people can have the same TNM stage and still have biologically very different tumours.
In ALK-positive lung cancer there is an ALK fusion or rearrangement. That molecular characteristic can be decisive in choosing a targeted treatment. This is why biomarker testing matters so much.
In a recent article, Lung Cancer Europe discusses whether the classic TNM system is still sufficient now that molecular features play an increasingly important role. A possible future model is mentioned: TNM + DB.
- D for Driver: is there a molecular change for which a targeted treatment is available and supported by evidence in that disease setting?
- B for Biology/Burden: is there still molecular evidence of cancer detectable, for example through ctDNA?
CtDNA is tumour DNA that can be found in the blood. Among other things, researchers are looking at whether the presence of ctDNA after treatment with curative intent can help identify patients at higher risk of the disease returning.
Important: TNM + DB is not currently a new official staging system. TNM remains the standard.
For people with ALK-positive lung cancer, this discussion underlines one important point above all: the stage matters, but biomarker testing can provide additional information that may be decisive for treatment.
That is why it is important not only to ask:
“What stage do I have?”
but also:
“Has my tumour been comprehensively tested for biomarkers?”
Source and further reading: Lung Cancer Europe – Lung cancer staging: is TNM still enough?