PTH and chronic myelogenous leukemia, BCR-ABL1 positive: To our knowledge, this is the second case in the literature with the coexistence of two rare diseases, ADH1 and CML.In CML patients treated with TKIs, serum calcium levels should be monitored and, in the case of severe hypocalcemia accompanied by low or inappropriately normal PTH, the possible existence of ADH1 may need to be investigated.