From 9 to 11 September 2026, the European Testicular Tumor Network (ETTN) held its first Work Meeting in Prague. The hybrid meeting aimed to give the network a practical framework for international collaboration in the research, diagnosis, treatment, and long-term follow-up of patients with testicular cancer.
ETTN Lead Coordinator Ludmila Boubliková (Department of Oncology, First Faculty of Medicine, Charles University, and Thomayer University Hospital, Prague) organised the meeting. Thomayer University Hospital is an ERN eUROGEN Full Member, and representatives from other ERN eUROGEN healthcare providers (HCPs) also took part.
Why testicular cancer needs a European network
Testicular cancer is rare, but it is the most common solid cancer in young men. Its incidence continues to rise, and Europe has long recorded the highest rates in the world. The pattern is shifting, however. The highest incidence is moving away from Northern European countries such as Denmark and Norway towards Central and Southern Europe. According to GLOBOCAN 2024 data, Croatia, Switzerland, Slovenia, Montenegro and Hungary now rank first to fifth worldwide, with rates of 11–12 cases per 100,000 men.
More than 95% of patients achieve long-term remission across all disease stages, which makes testicular cancer one of the most curable cancers. Even so, it remains the leading cause of cancer-related death among young adult men, with a mortality rate of approximately 0.5 per 100,000. Treatment has changed little in many years. Few clinical trials focus on these tumours, and modern options such as targeted therapies are not available for this diagnosis.
Until recently, therapy targeting Claudin 6 (CLDN6), a protein highly expressed in 90–100% of testicular tumours, offered a promising new approach. Early-phase studies of the anti-CLDN6 therapy BNT211 showed highly encouraging responses, particularly in patients with testicular cancer. A phase II trial (BNT211-02) followed, but it was discontinued for testicular cancer after a short period and terminated early by the sponsor.
Treatment therefore still relies mainly on cisplatin-based chemotherapy. Once resistance to cisplatin develops, no other effective options are currently available. Fundamental questions also remain open: what causes testicular cancer and drives its biology, how treatment resistance develops, which biomarkers and prognostic factors are useful in clinical practice, and how best to care for survivors given the potential long-term effects of treatment.
A new European network for testicular cancer
The ETTN brings together clinicians from different specialities, scientists, researchers and patient organisations across Europe. Its aims are to accelerate testicular cancer research, translate findings into clinical practice as quickly as possible and improve patient outcomes. It currently includes experts from 10 European countries and the United States.
As a consortium of European centres dedicated to testicular cancer research and treatment, the network builds on the long tradition of the Copenhagen Testicular Cancer Workshops. It works closely with other germ cell tumour initiatives, including the Testicular Cancer Consortium (TECAC) and the Malignant Germ Cell International Consortium (MaGIC). It is also developing its activities within, and with the support of, two European Reference Networks: ERN EURACAN, for rare adult solid cancers, and ERN eUROGEN.
What the meeting covered
The programme focused on building the network’s organisational structure, coordinating research activities, preparing joint grant applications and developing educational initiatives.
Work Group sessions addressed:
- epidemiology and pathogenesis of testicular cancer
- tumour biology and pathological classification
- emerging biomarkers
- imaging techniques and surgical approaches
- clinical trials and new therapeutic strategies
- long-term consequences of treatment and quality of life among cancer survivors
Participants also explored ways to share data and biological samples, develop joint research projects, establish training and reference centres, and harmonise best practice in patient care.
Supporting and educating early-career researchers has long been a priority for the network. The ETTN also places strong emphasis on involving patient organisations in awareness-raising and in defining research priorities, so that patients’ perspectives and needs help shape the future of the field.
Get involved
Developing new therapies for testicular cancer is one of the most urgent, yet persistently overlooked, challenges in uro-oncology, and progress will depend on close international collaboration. The ETTN aims to provide a sustainable, long-term platform that links research and clinical practice.
Clinicians, researchers and patient organisations interested in the network’s work on testicular cancer can find out more at ettn.eu and ettw.eu, or contact the network at info@ettn.eu.
Within ERN eUROGEN, testicular cancer is covered by Expertise Area 3.2 in Workstream 3 (Oncology).
This event was supported by the ERDERA Networking Support Scheme (GA No. 101156595); grants from the Czech Ministry of Health – RVO (FTN – 00064190; FNMH – 00064203); the National Institute for Cancer Research project (EXCELES Programme, ID: LX22NPO5102), funded by the European Union – NextGenerationEU; and the Men Against Cancer Foundation.
