PET Scan in metastatic breast cancer

[Mjmumbai]

My mom 52 yr old was diagnosed with breast cancer (er/pr +ve, her2-ve) stage 4 with multiple bone mets in Jan 2016. She was started on letrozole daily since 1st week of feb and monthly zoledronic acid injection. She also took 5 radiations to the spine n rt hip for pain relief. She will be completing 3 months of letrozole in may. What should be the follow up at 3 months..does the 3 month follow up include pet scan in such pts? Or is it usually done at 6 months??

[roxboxfox RadiationOncologist]

Depends on affordability of the patient. These days patients themselves are aware about PET scan, so a clinician does not interfere...and PET scans are done. 

The traditional approach has been to do conventional contrast enhanced CT scans which is good enough to serve similar purpose. 

The whole idea is to compare scans regularly...every 3-4 months and change treatment if there is progression.

There will be loads of scans for her in future...as there is a long list of armamentarium available for her.

[har9505538462 in reply to roxboxfox]

Is it true more then 13 pet ct scan not to done for a single patient in his whole life? There is any limitation on pet ct scan test? 

[sumeet_shah Administrator in reply to har9505538462]

No

[Mjmumbai in reply to roxboxfox]

Thanks sir..my doctor was the opinion of not doing pet scan at 3 months and continuing with letrozole...will check with him again at the 3 month follow up

[roxboxfox RadiationOncologist]

No man. Have u got any reference. I m not aware personally but can find out from my nuclear medicine consultant friend.

You are exposed to some radionucleqr material... But risk of second cancer will be seen only after 15-20 years.

Which is not relevant for someone with an incurable metastatic breast cancer

Whose current life expectancy is under 5 years on an average.

[Jagdin]

Are there any other scans or diagnostic follow up tests apart from the PET scans and CT scans.

[roxboxfox RadiationOncologist]

In small subset of patients, there is a tumour marker CA 15-3 

Which if elevated cab be used in conjunction with scans..Its a crude marker and should not be used to change treatments.

It may he used to guide frequency of scans in poor patients not able to afford scans and /or help one decide about progression of cancer at times.

[Mjmumbai in reply to roxboxfox]

Ohk sir..no one ever mentioned abt tumor markers being used although I have read abt it's common practice in us n uk..also abt the pet scan he was not worried abt the affordability but more abt the fact that letroz will only show marginal improvement at 3 months. Still il confirm everything again at our next follow up. Thanks 

[roxboxfox RadiationOncologist]

For Advanced Mets Breast cancer.

The response rates with Letrozole is 32% and the median time to progression being 9.4 months.

30% patients would progress in first three months.

Ref: PO 25 TRIAL 

[sumeet_shah Administrator]

Planning for a cancer patient is a very individualized thing. For two patients of same age and same stage, the treatment may vary and so also the follow up investigations and everything else. We consider the burden of disease in a patient plan follow up and treatment accordingly. And like Dr. Rohit mentioned above, it is not always necessary to do PET. But many times, my patients insist on doing so (even when according to me it's not needed and we can do with a plain CT scan) and when it is so, we don't interfere in their decisions. We let them do it. 

Let your Oncologist decide on the follow up investigations needed for your mother.