Influence of National Comprehensive Cancer Network (NCCN) Guidelines on Clinical Practice in Patients with Chronic Myelogenous Leukemia (CML) Treated At a Single Academic Medical Center

Abstract 4433

One of the aims of the National Comprehensive Cancer Network (NCCN) is to provide physicians with state-of- the- art treatment pathways for specific malignancies. These guidelines are frequently updated, and disease- based committee members either meet or speak with each other at least once a year. However, it is not known to what extent these guidelines are actually used in clinical practice. In order to determine how physicians in a single large academic cancer center utilize NCCN guidelines for patients with chronic myelogenous leukemia (CML), we reviewed 20 randomly chosen patients with CML diagnosed between 2002 –2007 and 2008– 2010, using 2008 as the year when the more contemporary testing schedule for FISH and PCR was established. Nine physicians, median age 51 years (range 35–61) with a median clinical care experience of 21 years (range 2–30), cared for these patients. The median age of the patients was 58 (range 22–56), 11 were male, and median follow up was 4 years (range 1–8). Eleven patients began treatment in 2008 or later. CML guidelines were divided into two main components: (1) documentation of CML by bone marrow (BM) studies at time of diagnosis, and after 6 and 12 months of imatinib (IM) therapy, and (2) frequency of testing with either BM or peripheral blood (PB) FISH and PCR for BCR-ABL. Of the 20 patients, 17 had diagnostic BMs performed on their initial visit here, and 3 had PB confirmation of disease, having had BMs done on the outside 1, 2, and 5 months prior to their initial visit. Thirteen of the 20 patients had BMs performed after 6 months of IM therapy, and 11 had BMs performed at 12 months; 5 patients had negative karyotype and FISH studies on their 6^th month BM and thus did not have a repeat BM at month 12. Thus, NCCN guidelines were followed in 80% of patients. The most common deviation from NCCN guidelines was the frequency of interim PB and/or BM testing using FISH and PCR. While the median interval for PB testing was every 3 months (range 1 to 6), significant numbers of patients had much more frequent testing. For example, 13 of the 20 patients had serial PB FISH performed after at least one negative FISH result; 3 patients had > 5 samples analyzed and one patient had 10 samples tested after at least one negative result. In all these patients, subsequent FISH tests results after the first negative test were also negative. Two patients had BM testing performed after PB PCR was negative in at least two prior samples; BM PCR results were also negative. Three patients had simultaneous BM and PB PCR performed which provided similar results. At the time of last testing, 19 of the 20 patients had a complete cytogenetic response, 13 patients had a complete molecular response, and 6 patients had a major molecular response. One patient with significant co-morbidities took IM intermittently and had no response to therapy. There were no differences between the two groups with regards to frequency of BM or PB FISH or PCR testing. In summary, in this CML patient population, important therapeutic tests such as BM sampling at diagnosis and at treatment decision points (12 months) were met in the majority of patients. However, interim testing varied widely and in many instances, was redundant, even after publication of NCCN contemporary guidelines. In order to eliminate such unnecessary testing and conserve important resources, improved internal audits and communication between the laboratory and the clinical staff is needed.