Comparative Effectiveness of Risk-adapted Surveillance vs Retroperitoneal Lymph Node Dissection in Clinical Stage I Nonseminomatous Germ Cell Testicular Cancer: A Retrospective Follow-up Study of 81 Patients

Management of Germ Cell Tumours of the Testis in Adult Patients. German Clinical Practice Guideline Part I: Epidemiology, Classification, Diagnosis, Prognosis, Fertility Preservation, and Treatment Recommendations for Localized Stages

INTRODUCTION

This is the first German evidence- and consensus-based clinical guideline on diagnosis, treatment, and follow-up on germ cell tumours (GCTs) of the testis in adult patients. We present the guideline content in two publications. Part I covers the topic's background, methods, epidemiology, classification systems, diagnostics, prognosis, and treatment recommendations for the localized stages.

METHODS

An interdisciplinary panel of 42 experts including 1 patient representative developed the guideline content. Clinical recommendations and statements were based on scientific evidence and expert consensus. For this purpose, evidence tables for several review questions, which were based on systematic literature searches (last search was in March 2018) were provided. Thirty-one experts entitled to vote, rated the final clinical recommendations and statements.

RESULTS

We provide 161 clinical recommendations and statements. We present information on the quality of cancer care and epidemiology and give recommendations for staging and classification as well as for diagnostic procedures. The diagnostic recommendations encompass measures for assessing the primary tumour as well as procedures for the detection of metastases. One chapter addresses prognostic factors. In part I, we separately present the treatment recommendations for germ cell neoplasia in situ, and the organ-confined stages (clinical stage I) of both seminoma and nonseminoma.

CONCLUSION

Although GCT is a rare tumour entity with excellent survival rates for the localized stages, its management requires an interdisciplinary approach, including several clinical experts. Quality of care is highly related to institutional expertise and can be reassured by established online-based second-opinion boards. There are very few studies on diagnostics with good level of evidence. Treatment of metastatic GCTs must be tailored to the risk according to the International Germ Cell Cancer Collaboration Group classification after careful diagnostic evaluation. An interdisciplinary approach as well as the referral of selected patients to centres with proven experience can help achieve favourable clinical outcomes.

Risk-adapted treatment reduced chemotherapy exposure for clinical stage I pediatric testicular cancer

BACKGROUND

Different from adult clinical stage I (CS1) testicular cancer, surveillance has been recommended for CS1 pediatric testicular cancer. However, among high-risk children, more than 50% suffer a relapse and progression during surveillance, and adjuvant chemotherapy needs to be administered. Risk-adapted treatment might reduce chemotherapy exposure among these children.

METHODS

A decision model was designed and calculated using TreeAge Pro 2011 software. Clinical utilities such as the relapse rates of different groups during surveillance or after chemotherapy were collected from the literature. A survey of urologists was conducted to evaluate the toxicity of first-line and second-line chemotherapy. Using the decision analysis model, chemotherapy exposure of the risk-adapted treatment and surveillance strategies were compared based on this series of clinical utilities. One-way and two-way tests were applied to check the feasibility.

RESULTS

In the base case decision analysis of CS1 pediatric testicular cancer, risk-adapted treatment resulted in a lower exposure to chemotherapy than surveillance (average: 0.7965 cycles verse 1.3419 cycles). The sensitivity analysis demonstrated that when the relapse rate after primary chemotherapy was ≤ 0.10 and the relapse rate of the high-risk group was ≥ 0.40, risk-adapted treatment would result in a lower exposure to chemotherapy, without any association with the proportion of low-risk patients, the relapse rate of the low-risk group, the relapse rate after salvage chemotherapy or the toxicity utility of second-line chemotherapy compared to first-line chemotherapy.

CONCLUSIONS

Based on the decision analysis, risk-adapted treatment might decrease chemotherapy exposure for these high-risk patients, and an evaluation after orchiectomy was critical to this process. Additional clinical studies are needed to validate this statement.