C91.90: Lymphoid leukaemia, unspecified Without mention of complete remission

You have blood cancer (leukemia).

With blood cancer, a blood cell divides uncontrollably and much too often. There are then far too many blood cells and they cannot work properly either. The diseased blood cells also crowd out the healthy blood cells. This means there are often too few healthy blood cells. A distinction is made between 3 different types of blood cell:

  • Red blood cells are important for carrying oxygen in the blood.
  • White blood cells are part of the body’s immune system. They fight pathogens.
  • Platelets are important for clotting blood.

Blood cancer symptoms are dependent on how many diseased blood cells and how many healthy blood cells there are. You can have prolonged bleeding or develop bruises for no reason. You may then be ill much more often and more seriously. You may also feel generally weak, anaemic.

Not all blood cancers are the same. There are different types of blood cancer. For example, it is possible to differentiate from which blood cell the blood cancer originated. In your case, a subtype of immune cell is affected.

Another distinction is the course of the disease. There are types of blood cancer that cause serious symptoms in a short time. But there are also types of blood cancer that are discovered accidentally and only cause a few symptoms at the beginning.

Additional indicator

On medical documents, the ICD code is often appended by letters that indicate the diagnostic certainty or the affected side of the body.

  • G: Confirmed diagnosis
  • V: Tentative diagnosis
  • Z: Condition after
  • A: Excluded diagnosis
  • L: Left
  • R: Right
  • B: Both sides

Further information


This information is not intended for self-diagnosis and does not replace professional medical advice from a doctor. If you find an ICD code on a personal medical document, please also note the additional indicator used for diagnostic confidence.
Your doctor will assist you with any health-related questions and explain the ICD diagnosis code to you in a direct consultation if necessary.


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