Any suggestions on which type of leukemia involves immature white blood cells, lymphocytic or myeloid?

Acute leukemia: Immature white blood cells called blast cells are found in acute leukemia- both in acute lymphoblastic and myelogenous leukemia. It also can be seen in chronic myeloid leukemia- especially in certain phase of the disease.

Several...: There are multiple types of leukemia including lymphocytic or myeloid. If the cells in question are immature, it is more likely the leukemia is an acute rather than chronic type; however, chronic leukemias can also have immature cells. The most likely answer to your question would be acute lymphoblastic leukemia and acute myeloid leukemia, but these too have multiple subtypes.