Prediction of relapse after lymph node dissection for germ cell tumours: can salvage chemotherapy be avoided?

Salvage chemotherapy has been used by some oncology centres for patients with residual malignant or immature elements in retroperitoneal lymph node dissections removed for metastatic non-seminomatous germ cell tumours. However, surveillance of these patients shows that many are cured by surgery alone. 118 retroperitoneal lymph node dissections for metastatic non-seminomatous germ cell tumours were reviewed and the morphology seen within them was quantified. 28 of these had immature or malignant elements and had been treated by surveillance before administration of further chemotherapy. The proliferation rate in these cases was assessed by immunochemistry. The proliferation index and the amount of embryonal carcinoma (EC) were both predictors of recurrence and therefore the need for further chemotherapy. Patients with greater than 25% of EC had an 84% chance of relapse and those with a Ki-67 index of greater than 50% had a 71% chance of relapse. The two tests had a positive predictive value of 83% and 71%, respectively. Patients with such a high risk of recurrence could be considered for post-operative adjuvant therapy at this point whilst others would be suitable for a watchful waiting approach.