Immature teratomas: identification of patients at risk for malignant recurrence

We investigated the significance of immature elements in an otherwise benign teratoma in 28 patients with immature teratomas diagnosed and treated at the Childrens Hospital of Los Angeles from 1941 to 1986. Different characteristics, including age, sex, primary tumor site, type of surgery (complete resection vs. partial resection or biopsy), and preoperative levels of alpha-fetoprotein (AFP) were analyzed to evaluate their association with risk of subsequent local malignant recurrence. After a median follow-up of 6 years, 21 patients are alive with no recurrence of the tumor (72% event-free survival). One patient died from infection after surgery and six patients had local malignant tumor recurrence within 1 year from diagnosis. Of the 28 patients, 12 had AFP levels measured at diagnosis. Eight patients had normal levels with no further evidence of tumor recurrence, and four had elevated levels with three tumor recurrences. Our experience demonstrates that only at the time of diagnosis do AFP levels correlate with a subsequent malignant behavior of these tumors (P = .004). Those patients with immature teratomas and elevated AFP levels at diagnosis should receive adjuvant chemotherapy after the initial surgical resection.