EFO_1000603 (Unclassified Renal Cell Carcinoma) is a renal cell carcinoma characterized by morphologic features that do not fit easily into one of the other well-defined categories of renal cell carcinoma. Examples of such features include mixtures of morphologic patterns, mucin production, and sarcomatoid morphology. Also known as: unclassified renal cell cancer, unclassified renal cell carcinoma.