Second edition ICCR dataset for testicular germ cell tumours: a reporting guide for histopathological diagnosis of orchiectomy specimens

Abstract

To summarise the content and significance of the recently published second edition International Collaboration on Cancer Reporting (ICCR) histopathology dataset for testicular germ cell tumours, covering the Orchiectomy specimen dataset. We highlight key updates from the first editions, including alignment with the 5th edition World Health Organization (WHO) Classification, revised staging criteria, clarified core data elements versus non-core elements and the evidentiary basis underpinning these changes. A review of the ICCR 2nd edition dataset for Orchiectomy specimens of primary testicular tumours was performed, focusing on their development by an international expert committee using a consensus-based approach. Core (required) and non-core (recommended) data elements were identified along with the level of evidence supporting each, following National Health and Medical Research Council (NHMRC) criteria. Changes from the first edition were extracted by comparing dataset content and notes, informed by up-to-date literature through July 2024. The 2nd edition Orchiectomy dataset provides an integrated, harmonised framework for reporting testicular germ cell tumours. The dataset incorporates the WHO 5th Edition Classification of Urinary and Male Genital Tumours. Pathological staging criteria have been updated to align with the 8th edition Union for International Cancer Control (UICC)/American Joint Committee on Cancer (AJCC) tumour-node-metastasis (TNM) definitions. The second edition of this dataset includes changes to align the dataset with the WHO Classification of Tumours, Urinary and Male Genital Tumours, 5th edition, 2022. The ICCR dataset includes the 5th edition Corrigenda, July 2024. It was agreed that this dataset is not suitable for non-germ cell tumours, with the hope that a new dataset, especially for sex-cord stromal tumours, would be developed. The 2nd edition Orchiectomy dataset represents an authoritative, up-to-date standard for pathology reporting of primary testicular germ cell tumours. By incorporating the WHO 5th edition classifications, current TNM staging and the latest evidence on prognostic factors, this dataset facilitates uniform reporting and prognostication. The ICCR dataset underscores core data required for patient management decisions (e.g., adjuvant therapy in Stage I disease, post-chemotherapy management) while providing flexibility through non-core elements for additional useful information. Adoption of this internationally vetted dataset will enhance consistency, assist multidisciplinary treatment planning and align pathology reports with modern consensus guidelines and classifications. The dataset can be used in both high-resource and limited-resource settings without compromising the essential reporting standards.