Good question! The forms of Leukemia (ALL, AML, CLL, and CML) also involve the bone marrow, and they share characteristics with AA, MDS, and PNH, with overlapping causes, symptoms, diagnostic tests, underlying biology, and some treatment approaches.
It's an arbitrary cutoff when they classify patients with multiple cytopenias, cell dysplasia, and 19% bone marrow blasts as MDS-RAEB-2 and patients with multiple cytopenias, cell dysplasia, and 20% bone marrow blasts as AML.
On the flip side, there are medical differences between these groups of diseases:
- AA, MDS, and PNH usually involve low blood counts, with their associated symptoms and treatments, while leukemias usually involve blood cell proliferation.
- Medical practitioners classify the diseases separately, with research, medical statistics, and drug trials usually focused on one type or the other.
We purposely limited the scope of Marrowforums for several reasons:
- AA, MDS, and PNH are rare, while leukemias are unfortunately common. Discussions and information about AA/MDS/PNH can easily get lost in the forest of discussions and information about leukemia.
- This site grew out of an email discussion group for AA and MDS patients, founded by volunteers for the Aplastic Anemia & MDS International Foundation (AA&MDSIF), so we inherited the same patient population.
- There are already many resources available for leukemia patients, including the Leukemia and Lymphoma Society and, since 2009, its LLS discussion boards.
That's not to say that you can't talk about the forms of myeloid leukemia here. But patients and family members dealing with AML and CML may be better served by seeking information from leukemia-focused sites and organizations.
Just as the AA&MDSIF's name doesn't mention PNH, but they're just as devoted to helping PNH patients as AA and MDS patients, we want to serve people with pure red cell aplasia (PRCA), people with undiagnosed low blood counts, and other conditions that sometimes overlap, such as myelofibrosis. We've focused on acquired diseases but occasionally hear from people with inherited anemias like Diamond-Blackfan anemia, thalassemia, and Fanconi anemia.
Bottom line: These forums are focused on a few diseases, but they are open to everyone they can help!