normal range for ca125
Reference Range. CA 125 is the only tumor marker recommended for clinical use in the diagnosis and management of ovarian cancer. The reference range of CA 125 is 0-35 units/mL (0-35 kU/L).The cutoff of 35 kU/L for CA 125 was determined from the distribution of values in healthy individuals to include 99% of the normal population.eference Range. CA 125 is the only tumor marker recommended for clinical use in the diagnosis and management of ovarian cancer. The reference range of CA 125 is 0-35 units/mL (0-35 kU/L).