Key Points for This Section

Myelodysplastic/myeloproliferative disease, unclassifiable, is a disease that has features of both myelodysplastic and myeloproliferative diseases but is not chronic myelomonocytic leukemia, juvenile myelomonocytic leukemia, or atypical chronic myelogenous leukemia. Possible signs of chronic myelomonocytic leukemia include fever, feeling very tired, and weight loss.

Myelodysplastic/myeloproliferative disease, unclassifiable, is a disease that has features of both myelodysplastic and myeloproliferative diseases but is not chronic myelomonocytic leukemia, juvenile myelomonocytic leukemia, or atypical chronic myelogenous leukemia.

In myelodysplastic /myeloproliferative disease, unclassifiable (MDS/MPD-UC), the body tells too many blood stem cells to develop into red blood cells, white blood cells, or platelets. Some of these blood stem cells never become mature blood cells. These immature blood cells are called blasts. Over time, the abnormal blood cells and blasts in the bone marrow crowd out the healthy red blood cells, white blood cells, and platelets.

MDS/MPD-UC is a very rare disease. Because it is so rare, the factors that affect risk and prognosis are not known.

Possible signs of chronic myelomonocytic leukemia include fever, feeling very tired, and weight loss.

These and other symptoms may be caused by MDS/MPD-UC. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:

• Fever or frequent infections.
• Shortness of breath.
• Feeling very tired and weak.
• Pale skin.
• Easy bruising or bleeding.
• Petechiae (flat, pinpoint spots under the skin caused by bleeding).
• Pain or a feeling of fullness below the ribs.

Glossary Terms

Not normal. An abnormal lesion or growth may be cancerous, premalignant (likely to become cancer), or benign.

An immature blood cell.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

A group of diseases in which the bone marrow does not make enough healthy blood cells. Also called preleukemia and smoldering leukemia.

A group of slow growing blood cancers, including chronic myelogenous leukemia, in which large numbers of abnormal red blood cells, white blood cells, or platelets grow and spread in the bone marrow and the peripheral blood.

Pinpoint, unraised, round red spots under the skin caused by bleeding.

A type of blood cell that helps prevent bleeding by causing blood clots to form. Also called a thrombocyte.

The likely outcome or course of a disease; the chance of recovery or recurrence.

RBC. A cell that carries oxygen to all parts of the body. Also called RBC and erythrocyte.

Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

Refers to a blood cell that does not contain hemoglobin. White blood cells include lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. These cells are made by bone marrow and help the body fight infections and other diseases. Also called WBC.