The presence of certain proteins can be measured on tissue samples. For tumour types such a lymphomas it is possible this way to determine whether the tumour consists of B or T cells. This information is not only important for the prognosis, but also for the choice of the proper treatment.
Immunophenotyping can also be done on other samples than tissue: the presence of certain proteins can also be determined on aspirates. This can be done via lab techniques such as flow cytometry, PCR and immunocytochemistry. Histopathology is in general the most appropriate test to do immunophenotyping with, followed by flow cytometry, PCR and finally immunocytochemistry.