Ejaculatory function in stage T1 nonseminomatous germ cell tumors: retroperitoneal lymph node dissection versus surveillance--a decision analysis.

Abstract

Ejaculatory function remains a major concern for patients with low stage nonseminomatous germ cell tumors of the testis. Whereas, it has been extensively studied in patients undergoing retroperitoneal lymph node dissection, preservation of ejaculatory function on surveillance protocols has not been studied. To compare ejaculatory function for surveillance protocols to primary retroperitoneal lymph node dissection appropriately, we constructed a decision analysis model mimicking the standard treatment algorithm for stage 1 nonseminomatous germ cell tumor of the testis. The primary clinical payoff for this study is ejaculatory function. Based on this model, we established that a primary nerve sparing retroperitoneal dissection must be performed with a 96.8% ejaculatory function rate to be recommended as the appropriate therapy. However, if a highly skilled surgeon routinely performs post-chemotherapy dissection with an ejaculatory function rate of 69.2% or greater, surveillance should be offered as the primary treatment modality. This result simply demonstrates a high skill level to allow the surgeon to salvage ejaculatory function in post-chemotherapy retroperitoneal lymph node dissection settings. If this level cannot be achieved, primary retroperitoneal lymph node dissection is the best choice. If we account for a 10% loss of ejaculatory function from primary chemotherapy, the minimum ejaculatory function rate for primary retroperitoneal dissection decreases to 95.7%. In the post-chemotherapy setting an 85.7% ejaculatory function rate must be achieved for surveillance to be considered the optimal choice. Clearly, less surgical rigor is needed with a primary retroperitoneal lymph node dissection when correcting for the effects of chemotherapy on ejaculatory function. Despite this fact, 1-way sensitivity analysis revealed that our model is insensitive to the ejaculatory function effects of chemotherapy. Furthermore, if the likelihood of recurrence on surveillance is greater than 16%, primary nerve sparing retroperitoneal lymph node dissection should again be recommended. Thus, to maximize ejaculatory function for patients with stage 1 nonseminomatous germ cell tumor a nerve sparing primary retroperitoneal lymph node dissection should always be performed, unless the likelihood of recurrence on surveillance is low or the surgical skill level allows for a highly successful post chemotherapy nerve sparing dissection.