Significance of serum concentrations of carcinoembryonic antigen, ferritin, and calcitonin in breast cancer.

Serum concentrations of carcinoembryonic antigen (CEA), ferritin, and calcitonin were measured in 107 patients with breast cancer, 80 of whom had overt or occult metastatic disease. CEA and ferritin values were statistically higher in those patients with metastases. In contrast, there was no correlation between calcitonin concentrations and the stage of the disease. All 27 subjects with CEA concentrations greater than 80 microgram/liter and 32 of 40 with values between 41-80 microgram/liter had metastatic disease. Ferritin was a definite but less sensitive discriminator, with metastatic disease present in all nine patients having concentrations greater than 400 microgram/liter. Such metastases were invariably hepatic. When the two measurements were used as a combined discriminant, the diagnostic accuracy increased somewhat. All 32 patients with CEA concentration greater than microgram/liter and/or a ferritin concentration greater than 400 microgram/liter had metastatic disease; the same was true for 32 of the 42 subjects with CEA concentration between 41-80 microgram/liter and/or a ferritin concentration between 200-400 microgram/liter. The measurements had prognostic value, both when assessed alone and together, with a median survival from the time of study significantly shorter in those with the highest values.