Response to TreatMent

When you have treatment for Waldenstrom’s macroglobulinaemia, your doctor will monitor you to see how well the treatment is working and whether you are getting side effects from the treatment.

Response to treatMent

They’ll use different tests to look for signs of your Waldenstrom’s macroglobulinaemia, like blood tests to detect certain proteins and scans to search for other signs of the disease. By looking at the results of these tests and talking to you about your symptoms, your doctor can tell how well the treatment is working. This is known as your ‘response’ to treatment and will help your doctor to decide if you need further treatment or if you can go back to active monitoring.

Waldenstrom’s macroglobulinaemia cannot be cured, but treatment can put the disease into remission – where the signs and symptoms of the disease are gone or reduced. These periods of remission can last for months or even years before the abnormal WM cells build up enough to give you WM symptoms. You may hear both ‘remission’ and ‘response’ used.

Measuring response to treatment

There are different ways to measure people’s response to various treatments. They measure how treatment affects someone’s Waldenstrom’s macroglobulinaemia immediately, but also in the longer term.

You may come across the following terms when reading or talking about a treatment’s effectiveness:

Depth of response: a way for researchers to quickly measure how your Waldenstrom’s macroglobulinaemia has been affected during and immediately after treatment. You might hear terms like ‘complete response’, or ‘partial response’. These terms are sometimes used outside of clinical trials. We go into these phrases in more detail below.
Progression free survival (PFS): how long a person lives with their Waldenstrom’s macroglobulinaemia without an increase in IgM levels or their symptoms becoming worse. Some drugs might not kill all the WM cells in your body but lead to long periods where your WM doesn’t get worse. For some people with WM, this is a preferable option to other treatments that might kill more abnormal cells but make them very ill in the process.
Time to next treatment: this is a helpful measurement as it can show how long-lasting the treatment. It is the time between one treatment and the next.
Overall survival (OS): how long people live on average after their treatment. You may hear this in terms of years e.g. ‘5 year survival’. This refers to how many people are alive at least 5 years after treatment.

Depth of response

In clinical trials, researchers use terms to describe how people have responded to treatment. This helps them to quickly measure the effectiveness of a treatment, and is sometimes used to predict how long the remission is likely to last for, especially in clinical trials. You may come across these terms even if you’re not in a clinical trial. However, they don’t give the full picture – for example some treatments rarely lead to a complete response but remain very effective treatments.

Try not to put too much emphasis on the numbers talked about below. Outside of a clinical trial, the specific numbers carry less meaning – there is likely to be very little difference between someone whose IgM has decreased by 49% (minor response) compared to someone whose IgM has decreased by 51% (partial response) even though this would put them in a better response category.

Response Terms used in Clinical Trials

Can sometimes be called ‘No Evidence of Disease’ (NED)
Blood tests show no sign of abnormal IgM
Your levels of IgM are normal
If you had swelling in the lymph nodes or spleen, this has gone
Bone marrow biopsy results are normal

Abnormal IgM proteins show up in your blood tests
Your levels of IgM are at least 90% lower than they were at the start of treatment
If you had swelling in the lymph nodes or spleen, this has gone
You have no new signs or symptoms of Waldenstrom’s macroglobulinaemia

Abnormal IgM proteins show up in your blood tests
Your levels of IgM have been reduced by at least 50% but no more than 90% from the start of treatment
If you had swelling in your lymph nodes or spleen, this may still be present but reduced
You have no new signs or symptoms of Waldenstrom’s macroglobulinaemia

Abnormal IgM proteins show up in your blood tests
Your levels of IgM have been reduced by at least 25% but no greater than 50% from the start of treatment
You have no new signs or symptoms of Waldenstrom’s macroglobulinaemia

Abnormal IgM proteins show up in your blood tests
Your levels of IgM have been reduced by less than 25%, or haven’t increased by more than 25% from the start of treatment
Any swelling you had in your lymph nodes or spleen hasn’t reduced but it hasn’t progressed (become more swollen) either
You have no new signs or symptoms of Waldenstrom’s macroglobulinaemia

Your levels of IgM have increased by 25% or more from their lowest point
Your signs and symptoms have progressed (become worse)