When tumor cells are poorly differentiated, and it is not possible to determine their lineage/origin based on their appearance, we are pleased to offer ICC in-house for cytology samples when indicated. The sample required for ICC submission is simply 4 adequately cellular, unstained or stained, air-dried glass slides prepared the same way as those for standard cytologic evaluation. ICC analysis does not require overnight shipping of cells in a fluid medium (as with flow cytometric analysis) or an incisional biopsy (as with IHC).