Thierry J Molina1, Maria V Bluthgen2, Lara Chalabreysse3, Vincent T de Montpréville4, Anne de Muret5, Romain Dubois6, Véronique Hofman7, Sylvie Lantuejoul8, Cécile le Naoures9, Audrey Mansuet-Lupo10, Marie Parrens11, Nicolas Piton12, Isabelle Rouquette13, Véronique Secq14, Nicolas Girard15, Alexander Marx16, Benjamin Besse2. 1. Department of Pathology, AP-HP, INSERM U1163, Institut Imagine, Hôpital Universitaire Necker-Enfants-Malades, Université de Paris, Paris, France. Electronic address: thierry.molina@aphp.fr. 2. Department of Cancer Medicine, Gustave Roussy, Villejuif, France. 3. Department of Pathology, Groupement Hospitalier Est, Hospices Civils de Lyon, France. 4. Department of Pathology, Institut d'oncologie thoracique, Hôpital Marie-Lannelongue, Le Plessis-Robinson, France. 5. Department of Pathology, CHU de Tours, France. 6. Institute of Pathology, CHU de Lille, France. 7. University Côte d'Azur, Laboratory of Clinical and Experimental Pathology, FHU OncoAge, Pasteur Hospital, Biobank, 0033-00025, Nice, France. 8. Department of BioPathology, CHU de Centre Léon Bérard, Lyon, and Grenoble Alpes University, Grenoble, France. 9. Department of pathology, CHU Rennes, Rennes, France. 10. Department of Pathology, AP-HP, INSERM U1138, Centre de Recherche des Cordeliers, Hôpital Universitaire Cochin, Université de Paris, Paris, France. 11. Department of Pathology, CHU de Bordeaux, INSERM U1053, Université de Bordeaux, 146 rue Léo Saignat, 33076, Bordeaux, France. 12. Rouen University Hospital, Department of Pathology, F 76 000, Rouen, France. 13. Department of Pathology, CHU Toulouse Oncopole, 1 avenue I Joliot Curie, 31059, Toulouse, France. 14. Department of Pathology, Hôpital Nord, AP-HM, Marseille, France. 15. Université de Lyon, Université Claude Bernard Lyon 1, Hospices Civils de Lyon, Lyon, France; Institut Curie, Paris, France. 16. Institute of Pathology, Mannheim Medical University, Heidelberg University, Mannheim, Germany.
Abstract
BACKGROUND: Classification of thymic epithelial tumours (TETs) is known to be challenging; however, the level of discordances at a nationwide level between initial and expert diagnosis and their clinical consequences are currently unknown. RYTHMIC is a national network dedicated to the management of TET based on initial histological diagnosis, followed by an additional expert review of all cases. Our aim was to evaluate the discordances between initial and expert diagnoses and whether they would have led to different clinical management. PATIENTS AND METHODS: We conducted a retrospective analysis of the cohort of patients discussed at RYTHMIC tumour board from January 2012 to December 2016. Assessment of disagreement was made for histological typing and for staging. The discordances were classified as major or minor based on whether they would have changed or not the proposed therapeutic strategy, respectively. Follow-up of the patients with major discordances was conducted until December 2018. RESULTS: Four hundred sixty-seven patients were reviewed, and 183 (39%) discordances were identified either related to histological subtype (132) and/or stage (72). Major discordances were identified in 27 patients (6%). They included 16 patients with TET for whom treatment recommendation based on the central review would have been post-operative radiotherapy, whereas it had not been the case. However, follow-up did not show any progression among the 15 patients with high-grade histology and/or stage resected thymomas. On the other hand, among the remaining 11 patients including 7 with a diagnosis other than TET, the overall management or follow-up would have been completely different with the expert diagnosis. CONCLUSION: Our real-life cohort reveals a high level of discordances considering TET diagnosis and supports expert review for optimal clinical management.
BACKGROUND: Classification of thymic epithelial tumours (TETs) is known to be challenging; however, the level of discordances at a nationwide level between initial and expert diagnosis and their clinical consequences are currently unknown. RYTHMIC is a national network dedicated to the management of TET based on initial histological diagnosis, followed by an additional expert review of all cases. Our aim was to evaluate the discordances between initial and expert diagnoses and whether they would have led to different clinical management. PATIENTS AND METHODS: We conducted a retrospective analysis of the cohort of patients discussed at RYTHMIC tumour board from January 2012 to December 2016. Assessment of disagreement was made for histological typing and for staging. The discordances were classified as major or minor based on whether they would have changed or not the proposed therapeutic strategy, respectively. Follow-up of the patients with major discordances was conducted until December 2018. RESULTS: Four hundred sixty-seven patients were reviewed, and 183 (39%) discordances were identified either related to histological subtype (132) and/or stage (72). Major discordances were identified in 27 patients (6%). They included 16 patients with TET for whom treatment recommendation based on the central review would have been post-operative radiotherapy, whereas it had not been the case. However, follow-up did not show any progression among the 15 patients with high-grade histology and/or stage resected thymomas. On the other hand, among the remaining 11 patients including 7 with a diagnosis other than TET, the overall management or follow-up would have been completely different with the expert diagnosis. CONCLUSION: Our real-life cohort reveals a high level of discordances considering TET diagnosis and supports expert review for optimal clinical management.