Clinical significance of serum ferritin in patients with renal cell carcinoma.

OBJECTIVES

We examined the serum ferritin levels in 158 patients with renal cell carcinoma and 101 healthy control subjects between 1987 and 1994 to investigate the value of this intracellular protein as a tumor marker.

METHODS

Preoperative and postoperative serum ferritin values were analyzed and the patients were stratified to three groups accordingly: group 1, patients with normal values (N-N); group 2, those with preoperative high and postoperative normal (H-N); and group 3, those with preoperative normal or high with postoperative high ferritin levels (H-H).

RESULTS

The mean serum ferritin level in 101 healthy control subjects was 85.7 +/- 63.6 ng/mL (range, 3.7 to 265.2). The upper limit of normal, which was calculated by adding 2 standard deviations to the mean was 219.9 ng/mL. Mean serum ferritin in patients with renal cell carcinoma was 274.2 +/- 276.3 ng/mL, which was significantly higher than that of control values (P < 0.01). The sensitivity, specificity, and overall accuracy rate for ferritin increase was 94%, 50%, and 61%, respectively. Multivariate analysis showed that the aforementioned grouping and stage of the disease were the two independent prognostic parameters. Preoperative ferritin levels lost its significance on multivariate analysis.

CONCLUSIONS

Our study shows that although serum ferritin was a useful tool in diagnosing and staging patients, it was not ideal in early stages. However serum ferritin seems to be more valuable for follow-up; postoperative values, indeed, predict the prognosis.