Diagnosing and Treating Myeloproliferative Neoplasms
Myeloproliferative neoplasms (MPNs) are “still in their infancy in the cancer world,” according to Rebecca N. Claassen, RN, BSN, OCN.
Rebecca N. Claassen, RN, BSN, OCN
Myeloproliferative neoplasms (MPNs) are “still in their infancy in the cancer world,” notes Rebecca N. Claassen, RN, BSN, OCN, who specializes in the care of patients with these blood disorders at the University of Kansas (KU) Cancer Center. Until 2008, MPNs were classified as myeloproliferative diseases, and like other rare cancers, the biggest challenge with MPNs is that they are not well-known.
MPNs include three disorders: polycythemia vera (PV) and essential thrombocytosis or thrombocythemia (ET), and primary myelofibrosis. PV and ET can progress to the most serious of the three conditions—myelofibrosis—a chronic blood cancer which involves a scarring of the bone marrow.
For patients with PV or ET, the severity varies by disease burden, but the prognosis is good. PV occurs when the body produces too many red cells and is most commonly seen in men >60 years. Therapeutic phlebotomy is the standard treatment, and if that’s not enough, explained Claassen, hydroxyurea, and in some cases, interferon, will be needed to treat the condition.
ET is marked by an increased number of platelets in the blood without a known cause. It is most prevalent in women >50 years, and frequent symptoms include blood clotting and bleeding. Claassen herself has ET, having been diagnosed shortly after she started working in the hematology clinic at the KU cancer center. She explained that her disease burden is very low, and she is being successfully treated with low-dose aspirin.
Myelofibrosis is treated with hydroxyurea, interferon, and ruxolitnib (Jakafi), which was approved by the FDA in 2011. Ruxolitinib is an oral JAK1 and JAK2 inhibitor typically prescribed in 15- to 20-mg doses twice daily. In 2014, the FDA extended its approval of the drug to patients with PV who are resistant or intolerant to hydroxyurea. An investigational agent to treat myelofibrosis, pacritinib, was placed on a “full clinical hold” by the FDA last month following reports of patient deaths related to intracranial hemorrhage, cardiac failure, and cardiac arrest in the phase III PERSIST-2 trial.
Because of the bone marrow’s inability to generate new blood cells in a patient with myelofibrosis, the liver and spleen become responsible for producing new blood cells. The spleen often becomes enlarged in these patients. Other health issues associated with the condition include anemia, night sweats, and muscle and bone pain.
Claassen, a 2015 recipient of one of CURE magazine’s MPN Hero Awards, stressed the importance of understanding the side effects of MPNs—not only the conditions themselves, but also their treatments.
“A lot of the side effects that people present with happen to go with older age, with the majority of people being diagnosed with these disorders in their 60s and 70s,” Claassen explained, for example, joint pain and fatigue, but these are also signs of MPNs.
“It’s important to know what those side effects are, and also what the side effects of the treatments are, to best support that patient,” she continued. She added that side effects should not be dismissed because patients are older, and nurses need to emphasize with patients that relief is available for their pain and fatigue.
As the nurse educator, she encourages her peers to keep up on the research by utilizing available resources, staying educated, and using the networks of specialized organizations like the MPN Research Foundation, because “the field is really so new and ever-evolving.”
Claassen also stressed the importance of participating in clinical trials, and this is especially true for the high-risk patient. She said that several myelofibrosis studies are under way at KU Cancer Center, and she encouraged nurses and patients to look for relevant trials which can be found on the National Institutes of Health ClinicalTrials.gov website.
“Nothing can cure these conditions, so we need new ways to slow them down and manage them.”
More Resources ...
The MPN Research Foundation (www.mpnresearchfoundation.org), the MPN Education Foundation (www.mpninfo.org), and the Leukemia & Lymphoma Society’s myeloproliferative neoplasm page at (www.lls.org) offer resources and information for HCPs, patients, and caregivers.