AIMS: Pharmaco-epidemiological surveys enable the frequency of serious adverse effects-and also the determining factors of their occurrence and seriousness-to be quantified. Few studies systematically gathering post-chemotherapy adverse effects data have been conducted. The objective was to assess the incidence of post-chemotherapy serious adverse effects on the basis of cancer registry data. METHODS: The population was composed of new invasive cancer cases, with the exception of haematopoietic tumours and cutaneous carcinomas. These cancers were identified in 2012 among patients living at the time of diagnosis in a region covered by a general cancer registry and by a French regional pharmacovigilance centre, and treated with neo-adjuvant and/or adjuvant first-intention chemotherapy, followed or not by radiotherapy. The study was based on a sample of 1000 patients from the registry, followed by the collection of serious adverse effects and the required information to constitute a pharmacovigilance file. RESULTS: Chemotherapy was associated with a particularly high incidence of serious adverse effects, affecting 44.5% (41.4-47.5%) of the patients. The highest incidence rates were observed when patients were exposed to topo-isomerase II inhibitors such as etoposide and bleomycin (69.2%), vinca-alkaloids (66.7%), topo-isomerase I inhibitors (54.5%) and platinum derivatives (52.0%). The clinical context was also linked to incidence, especially in case of metastases (53.3%) and comorbidities (51.3%). Substantial differences were found according to localisation, with a particularly high incidence in bronchial-pulmonary cancers (59.0%). CONCLUSION: The high overall incidence rate of serious adverse effects should motivate a reinforcement of information about drug toxicities and improve knowledge by drawing on patient reporting.