Bibliographical note

Funding Information:
We agree with Dieckmann [2] that there are several instances where a semen-based analysis is not applicable, that is, for detection of contralateral CIS. However, a semen-based method would be of great use in screening where CIS is suspected, and semen analysis could aid in selection of patients for biopsy, thereby decreasing the number of unnecessary surgeries. We agree here with van Casteren and colleagues that there is a large potential for a noninvasive detection method, best illustrated by the detection of CIS by the AP-2γ-based method in a young subfertile man, where testicular neoplasia was detected at the noninvasive stage due to his inclusion as a control subject in our studies [5] . Conflicts of interest : The studies of the Copenhagen group on various aspects of testicular cancer are supported by the Danish Medical Research Council, Vissing Foundation, Danish Cancer Society, Carla Thiel Kraghs Foundation, Kirsten & Freddy Johansen's Foundation, Danish National Advanced Technology Foundation, and Copenhagen University Hospital. A patent application covering the use of novel CIS markers for diagnosis of germ cell neoplasia is pending.