Risk-Adapted Approach Favoured for Stage I Seminoma

Prognostic risk factors for stage I seminoma relapse could help individualise treatment

  • Date: 12 Sep 2014
  • Author: Lynda Williams, Senior medwireNews Reporter
  • Topic: Germ Cell Tumours

medwireNews: Pooled results from three Spanish Germ Cell Cancer Group studies support a risk-adapted approach for the treatment of patients with stage I seminoma, say researchers who have used the findings to devise a nomogram to aid treatment decision-making.

They believe identification of reliable prognostic factors can help individualise treatment and reduce late treatment side effects, a significant concern in patients who are likely to be long-term survivors.

After a median of 80 months of follow-up, 11.1% of 744 patients participating in the three risk-adapted studies had relapsed, report Jorge Aparicio, from Hospital Universitario y Politécnico La Fe in Valencia, Spain, and co-workers.

This included 14.8% of the 396 low-risk patients who were recommended for surveillance after orchiectomy and 3.2% of the 348 high-risk patients who were given two courses of adjuvant carboplatin.

This gave an overall actuarial 5-year disease-free survival (DFS) rate of 92.3%; 88.3% for surveillance patients and 96.8% for adjuvant chemotherapy patients.

Writing in the Annals of Oncology, the researchers say that relapse occurred after a median of 14 months, with most (86%) cases occurring in the retroperitonenum (86%). Relapse characteristics did not significantly differ between the surveillance and carboplatin treatment groups.

And salvage treatment – consisting of chemotherapy (92%), radiotherapy (5%) or surgery plus chemotherapy (3%) - was effective in all patients, giving a 100% 5-year cause-specific survival rate.

Jorge Aparicio et al explain that patients in the first study were classified as low or high risk for recurrence according to the presence of vascular invasion or above T1 stage disease in the first study and this gave a 5-year actuarial DFS rate of 87.7%.

The second study defined high-risk disease as a tumour size greater than 4 cm and/or rete testis invasion, while the third study classified patients as high risk only if they had both criteria - actuarial 5-year DFS rates were 95.9% and 91.6% for these patient populations, respectively.

Further analysis found that rete testis invasion and tumour size were the best predictive factors for relapse; these were used to create a nomogram to predict an individual patient’s DFS probability and decide whether or not adjuvant carboplatin should be given.

“Future studies of molecular tumor characteristics or Gene signatures and improved imaging techniques may help to define the best approach to the management of stage I seminoma”, the researchers suggest.

For now, they believe the overall pooled relapse rate of 11.1% “compares favourably with the 15–20% attained in the surveillance studies, and the proportion of men treated with adjuvant therapy in our trials (46.8% overall) is significantly lower than in the studies of carboplatin or radiation therapy (100%).”

Jorge Aparicio and co-authors add: “We have also demonstrated that the incidence of relapses among patients with no risk factors (tumor size <4 cm and rete testis invasion) is only 8.3%.”

Reference

Aparicio J, Maroto P, del Muro G, et al. Prognostic factors for relapse in stage I seminoma: a new nomogram derived from three consecutive, risk-adapted studies from the Spanish germ cell cancer group.  Ann Oncol 2014; First published online 10 September. doi: 10.1093/annonc/mdu437

medwireNews (www.medwireNews.com) is an independent clinical news service provided by Springer Healthcare Limited.© Springer Healthcare Ltd; 2014