C96.9: Malignant neoplasm of lymphoid, haematopoietic and related tissue, unspecified

You have cancer of immune cells or blood stem cells.

There are various kinds of defense cells (immune cells) in the body. Specific immune cells produce antibodies in the blood. The antibodies cling to pathogens and foreign substances in the blood, for example. This allows the antibodies to make the pathogens and foreign substances visible to the immune system. The immune system helps the body to fight and eliminate diseases and foreign substances.

Blood stem cells are cells that can develop into different types of blood cells. Different types of stem cells and therefore also blood cells can be distinguished:

  • 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.

With cancer of the blood stem cells, these stem cells divide uncontrollably and much too frequently. There are then far too many stem cells and blood cells and they cannot work properly either. The diseased stem cells and blood cells can crowd out healthy cells. This means there are often too few healthy cells.

There are cancers of immune cells or of blood stem cells that cause serious symptoms in a short time, causing you to feel weak or have a fever, for example. You also sometimes lose weight. But there are also cancers of immune cells or of blood stem cells 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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