Can a CBC (blood test) show leukemia always?

Yes, most times. A leukemia typically begins in the bone marrow and will often show effects on the CBC as the cancer cells spill over into the circulating blood. On rare occasions leukemia may be still limited in the bone marrow, so we make a diagnosis by taking a bone marrow sample.

Related Questions

Could a CBC (blood test) show leukemia accurately always?

Sometimes. Sometimes but not always. Leukemia, a form of blood and bone marrow cancer, is frequently detectable in the blood; however, especially if early in the course of the disease, leukemic cells may be confined to the bone marrow and not cross into the blood in sufficient numbers to be detected by a cbc. Ultimately, the complete diagnosis and prognosis of leukemia relies on bone marrow examination. Read more...

I am a 66 yr old male and my blood test show a RDW-SD of 47.8fl and a RBC of 4.62mil All other CBC readings were normal. Is this a problem?

No. I would check your stool for occult blood in case this is very early iron deficiency perhaps due to a bleeding ulcer or tumor . Read more...
Incomplete info. The information you provided about RDW does not add up. However, if rest of the parameters are normal, this is not any thing to be concerned about. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex. Read more...