Determining progression

nnguyen

Hello, hope you would response to this question: when does your oncologist decide the cancer has progressed from current regimen?

1- A definitive trend in rising tumour's marker such as Ca27.29 or Ca15-3. Note that there are 7-10 benign causes of a jump in marker, although I haven't read any paper with respect to benign cause for definitive rising trend.

2- Imaging shows tumor increases in size regardless of the size increase

3- Imaging shows tumor increase in size and has to be at least "20% bigger" per RECIST 1.1 standard. If yes, is "20% bigger" in comparison to the previous scan or image from the scan at the start of the current regimen?

4- Imaging shows new tumor regardless of new tumor size

5- Imaging shows new tumor and its size must be bigger than imaging minimum resolution. For example, typical CT scan resolution is 5mm, so if the new tumor is less than 5mm, the scan result dims not definitive. Note newer CT machine has resolution of 1-3mm. Also reading images is very subjective (per radiologist) especially for small tumor. I looked at a few, it's really tough.

6- Some combination of above, if so please specify.

Thanks so much for your response.

Nguyen

Ps: If you are curious about Recist 1.1

https://radiologyassistant.nl/more/r...1/recist-1-1-1

https://ctep.cancer.gov/protocoldeve..._guideline.pdf

parakeetsrule

7. It depends. Everybody is different! It's not just by oncologist. It depends on each individual patient, their diagnosis, progression history, progression location, etc. Whether to change treatments can depend on treatment history, remaining available treatments, side effect tolerance, and risk tolerance.

nnguyen

Thank you for your response. But I am asking about "determining progression" only, and yes there are other factors (beside progression) to change regimen. Thanks again.

moth

It depends.

When I was in a trial, we lived by RECIST on the target lesions. (measured from start of current treatment, not from last scan)

Once off the trial, we're still sort of following recist.

New lesions in same organ while other things stay stable = progression but we have a couple times said wait & see till next scan.

New lesions in new organ while other things stay stable = definite progression

new lesions while other lesions shrink/disappear - that one has been trickier. We've waffled on it. I've had a lot of mixed responses with the immunotherapy. We've mostly tried to continue until it got to the point last Dec where there were too many new things to ignore.

Tumor markers - largely ignored as mine don't seem very much in sync with what is happening.

For some of these decisions *I* was the decision maker. About a year ago I had a mixed response scan & was given the option to switch treatments or wait another 3 months. I waited and the following scan was definitely back to reduction in lesions so I gambled well. I stayed on that treatment until my Dec 2021 scan which was more definitely a progression. My oncologist called it definite progression & I really couldn't argue otherwise so we changed treatment.

fwiw, other than a few things in my lymph nodes (all over) my tumors like to grow fast & big so we're not talking about mm changes. I'll go from nothing, nothing, nothing to a new 2cm tumor 12 weeks later. I think small mm changes that might be margin of error in measurement changes would give me more pause. But otoh, if there are a lot of them (instead of just one or two) then I'd probably also lean to calling that progression because even with margins of error in measurement, something is clearly happening

parakeetsrule

I know you're asking about progression. But my answer is still "it depends" and I think moth's response helps show why. It's not by oncologist, it's based on individual patients. For example, like her, tumor markers don't follow progression for many people. My oncologist told me they are too unreliable. Mine were actually completely normal even though I had cancer popping up all over. But for some people, they are extremely reliable and would indicate progression was occurring. So for that person the oncologist would follow them to help track progression.