To assess differences in the histopathological diagnoses of a series of paratesticular sarcomas following changes in the morphological classification of these tumours and the availability of investigations to define their immunophenotype, and to consider the impact of these changes on clinical management. Thirty-six soft tissue tumours of the paratesticular region, originally submitted to the British Testicular Tumour Panel and Registry between 1958 and 1967 were re-examined histologically using modern diagnostic criteria, including immunohistochemical features. Where possible, follow-up was brought up to date. Thirteen (35%) of the diagnoses made in 1967 were changed; of these, seven changes were attributable to the results of immunohistochemical tests and one involved the identification of an entity not recognized in 1967 (spindle cell rhabdomyosarcoma). The changes in diagnoses of major clinical relevance involved three neoplasms (8%) in which the recent opinion was rhabdomyosarcoma, a tumour for which successful treatment protocols are currently available.