Two CT scans needed to follow nonseminomatous tumors

September 1, 2006

Atlanta-Sixty percent of testicular germ cell tumors, such as embryonal cell carcinoma, teratocarcinoma, and teratoma, are nonseminomatous. Stage I nonseminoma patients are usually of young age, the cure rate is high, and most patients have many decades of life ahead after orchidectomy, followed by surveillance. Therefore, long-term investigations of morbidity and treatment are of significant concern.

Atlanta-Sixty percent of testicular germ cell tumors, such as embryonal cell carcinoma, teratocarcinoma, and teratoma, are nonseminomatous. Stage I nonseminoma patients are usually of young age, the cure rate is high, and most patients have many decades of life ahead after orchidectomy, followed by surveillance. Therefore, long-term investigations of morbidity and treatment are of significant concern.

Graham M. Mead, MD, of the Royal South Hants Hospital in Southampton, UK, presented results of a UK Medical Research Council study of different numbers of CT scans in the surveillance of patients with stage I nonseminomatous germ cell tumors of the testis at the American Society of Clinical Oncology annual meeting here. Dr. Mead and colleagues concluded that two CT scans at 3 and 12 months after orchidectomy is an effective approach to follow-up that reduces radiation exposure.

Surveillance is a standard management approach for stage I nonseminomatous germ cell tumors, but there is no agreement on the number of CT scans that are required to detect relapses.

In order to answer these concerns, Dr. Mead organized a randomized trial of two versus five CT scans to determine whether the number of scans influenced prognosis. Patients were randomized to chest and abdominal CT scans at either 3 and 12 months, or at 3, 6, 9, 12, and 24 months, with all other investigations, such as clinical exams, markers, and chest x-rays carried out at equal frequency in the two arms.

Two scans adequate

Between February 1998 and April 2003, 414 patients were randomized from 32 centers in the UK, Norway, Australia, and New Zealand. Of those patients, 247 were assigned to two CT scans and 167 to five CT scans. With a median follow up of 40 months, 37 relapses (15%) occurred in the two-scan arm, but 33 of those 37 relapsed patients remained alive and disease-free. There was no information available on the remaining four.

In the five-scan arm, 33 relapses (20%) have been reported, with 30 of them alive and disease-free. The remaining three were also alive, but a residual mass kept them under surveillance.

"This study can exclude with 95% probability an increase in the proportion of patients relapsing with intermediate-or poor-prognosis disease of more than 1.6% if they have two, rather than five CT scans as part of their surveillance protocol," Dr. Mead concluded. "CT scans at 3 and 12 months after orchidectomy should be considered the new standard and will be associated with a reduction in radiation exposure."

Maria DeSantis, MD, of the Kaiser Franz Josef Hospital in Vienna, Austria, who moderated the session, called this an "exciting trial," even though only a few high-risk stage I cases were included.

"Therefore, the study is not representative for an average stage I surveillance group," Dr. DeSantis told Urology Times. "There are still a lot of open questions concerning follow-up procedures. The CT frequency in the follow-up of high-risk stage I patients on surveillance and also for patients after adjuvant chemotherapy is still open. There is no consensus about the frequency and duration of follow-up visits with clinical examination, x-rays, and tumor markers.

"Further radiation reduction strategies, such as a change in operational settings and a reduction in the body volume scanned, should be considered."