Serum ferritin as a third marker in germ cell tumours.

Serial measurements of serum ferritin have been assessed as an additional marker in a study of 12 patients with germ cell tumours. The standard markers, serum AFP and beta HCG, were also assessed serially. During treatment elevated levels of serum ferritin were detected in 10 patients, elevated AFP in 10 patients and elevated beta HCG in 6 patients. A poor prognosis was associated with persistently raised serum ferritin and either, or both, elevated AFP and beta HCG levels. Decreasing levels of serum ferritin indicated favourable response to treatment; rising values were associated with recurrence or dissemination of tumour. Even if serum ferritin cannot be classed specifically as a tumour product, it may be useful in the early detection of residual or recurrent tumour.