Problems in crossmatching blood from cancer patients.

The term "cancer" is an umbrella for a large number of malignant diseases which vary in severity and type. Therefore, many problems are associated with crossmatching a patient with this diagnosis. Blood use may vary greatly in amount and in the urgency of its need. The diseases themselves may cause cold reactive auto agglutinins to appear. The diseases and their treatments may cause red cell antigenic structure to be modified or antibodies to decrease in strength. Multiple transfusions may induce the formation of multiple antibodies. A few blood groups have been associated with a higher incidence of carcinoma in the patients possessing them. All of these possibilities must be considered by the blood bank when a transfusion request for a patient with "cancer" is received.