During treatment for chronic myelogenous leukemia (CML), frequent tests are needed to determine how well people are responding to their medication. Key response “milestones” have identified that an earlier, more profound response translates to a better outcome over the longer term. For example, long-term survival is improved if a person can achieve better than a 1-log response within the first three months of starting a tyrosine kinase inhibitor (TKI, such as Gleevec, Tasigna, Sprycel or Bosulif).
To determine that response, doctors need to obtain blood or bone marrow samples to do PCR (polymerase chain reaction) testing. Frequent visits to the hospital or clinic can be something of a nuisance, but testing appears to have some less obvious benefits, according to a new analysis of health data (Latremouille-Viau and colleagues. ASCO 2016; abstract 318539). Results were presented at the American Society of Clinical Oncology (ASCO) annual meeting in Chicago.
The database included about 1,400 people with CML. Over a 1-year period, one-third had no PCR tests, 16% had one test, 15% had two tests, 18% had three tests, and 16% had four tests.
More frequent testing was associated with less time in hospital. For every added test, the number of in-hospital days decreased 13%. This may suggest that closer monitoring enables your doctor to manage some problems early before they become serious enough to require a hospital stay.
People who were being monitored more closely also showed better adherence to their medication regimen. Overall adherence was 86%, which translates to taking the medication about 26 days a month (over 90% adherence is recommended). But with each additional test, adherence improved by just over 2%. People were more likely to stick to the program if they had frequent tests. In effect, people were more likely to “study” if they knew there was a test coming up.