A transfusion medicine physician in an Eastern city of the USA states that colleagues at his institution ask the following: "One of the absolute indications for irradiated blood products is Hodgkin's disease. How long after diagnosis does this indication continue (only if active disease, 5 years after remission, forever?)" He wonders if the same question would apply to many acquired indications such as allogeneic stem cell transplant, autologous stem cell transplant, treatment for many hematologic malignancies, use of a purine analog, solid organ transplant using anti-thymocyte globulin, etc. Once a patient is essentially "cured" and is living a normal life, does he still need irradiated blood products to prevent TA-GVHD?

The above question was posed to Dr. Paul Holland (attribution used with permission) who replied as follows: "My first question would be why one of these patients would need a transfusion after being "cured" of the disease for which irradiated blood was appropriate in the first place? Are they in relapse or what else is going on to necessitate more transfusions? In any case, I think these patients should receive irradiated blood components for the rest of their lives. I cannot see how to give a meaningful time limit when their risk might be less without some data. I believe they would remain at risk, to some extent, so should ever after only get irradiated components, including supposedly "acellular" components like FFP and cryo which do have some viable lymphocytes in them despite the freezing without any cryoprotective agent."

The following comments have been received.

ADDENDA Sept. 1, 2005

1. The Quality Manager at Banco de Sangre y Tejidos de Cantabria in Santander, Spain reports that in their opinion, until sensitive, optimal, functional immunologic tests are available in clinical practice, candidates for product irradiation should receive such products indefinitely to avoid transfusion associated graft versus host disease (TA-GVHD), which is their practice. They base the aforementioned practice on the following assumptions:

• The logistic problems of flagging a patient for irradiation, then de-flagging, then re-flag if relapse... the potential errors could cause more harm than good.

• The difficulty in assessing with absolute assurance when a patient is cured of a neoplastic disease. This is even more evident for autoimmune diseases. Relapses can occur several years after an initial complete remission, so the patient could always be at risk. The immune alterations present in some neoplastic diseases could be present even after achieving a complete remission, and these could also be a risk factor for TAGVHD.

• The risk of TAGVHD is influenced by immune alterations in the host. In the case of transplantation, particularly allogeneic cases, immune recovery may take several years to be complete, and many patients take long term immunosuppresive treatment. Moreover, the effect of chemotherapy can cause long term lymphocytic impairment, years after the original disease is cured.

• Sometimes you cannot know if transfusion needs are caused by occult relapses of the original disease, specially in the emergency room setting.

• One could make the hypothesis that the immunosuppresive effects of transfusion which play a role in tumor relapse, could potentially be avoided by irradiation.

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Ira A. Shulman, MD
CBBS e-Network Forum Editor & Moderator