Non-clear cell renal cell carcinomas (nccRCC) represent a highly heterogeneous group of kidney tumors, consisting of the following subtypes: papillary carcinomas, chromophobe renal cell carcinoma, so-called unclassified carcinomas or aggressive uncommon carcinomas such as Bellini carcinoma, renal cell carcinoma (RCC) with ALK rearrangement or fumarate hydratase-deficient RCC. Although non-clear cell cancers account for only 15 to 30% of renal tumors, they are often misclassified and accurate diagnosis continues to be an issue in clinical practice. Current therapeutic strategy of metastatic nccRCC is based primarily on guidelines established for clear cell tumors, the most common subtype, however this approach remains poorly defined. To date, published clinical trials for all histological nccRCC subtypes have been collectively characterized into one group, in contrast to clear cell RCC, and given the small numbers of cases, the interpretation of study results continues to be challenging. This review summarizes the available literature for each nccRCC subtype and highlights the lack of supportive evidence from prospective clinical trials and retrospective studies. Future trials should evaluate treatment approaches which focus on a specific histological subtype and progress in treating nccRCC will be contingent on understanding the unique biology of their individual histologies.
Cancer treatment reviews. 2021 Apr 09 [Epub ahead of print]
Philippe Barthélémy, Nathalie Rioux-Leclercq, Constance Thibault, Carolina Saldana, Delphine Borchiellini, Christine Chevreau, Isabelle Desmoulins, Aurélien Gobert, Werner Hilgers, Ahmed Khalil, Nathalie Lemoine, Friederike Schlürmann-Constans, Sylvie Négrier
Medical Oncology Department, Institut de cancérologie Strasbourg Europe, Strasbourg University Hospital, Strasbourg, France. Electronic address: ., Department of Pathology, Rennes Hospital, IRSET, Rennes 1 University, France., Medical Oncology Department, Hôpital Européen Georges Pompidou, APHP, Paris, France., Medical Oncology, Hôpital Henri Mondor, APHP, Univ Paris Est Creteil, Créteil, France., Medical Oncology Department, Centre Antoine Lacassagne, Université Côte d'Azur, Nice, France., ICR IUCT-Oncopole Toulouse, France., Medical Oncology Department, Centre Georges-François Leclerc, Dijon, France., Medical Oncology Department, Pitié-Salpêtrière Hospital, APHP, Sorbonne University, Paris, France., Medical Oncology Department, Institut Sainte Catherine, Avignon, France., Medical Oncology Department, Tenon Hospital - APHP, Sorbonne University, Paris, France., Medical Oncology Department, Clinique Sainte Marie, Cambrai, France., Medical Oncology Department, CHRU Brest, Institut de Cancerologie et Hématologie, CHIC Quimper, France., University of Lyon, Centre Léon Bérard, Lyon, France. Electronic address: .