Fig. 4

Subtype prediction through PSA in formalin-fixed and paraffin-embedded (FFPE) tissue. A PSA based on fresh-frozen (FF) samples from 9 RCC were compared to PSA based on matching FFPE samples. Whole-transcriptome profiles generated by RNA-Seq for two ccRCC were obtained from Li et al. (marked by asterisks) [82]. The remaining 7 tumors (pRCC) from the present study have been analyzed using microarray technology. For all 18 samples, \({P}_{psa}\) was below 0.05. B–D PSA were determined for 92 FPPE tissues of cohort C4. Gene expression was quantified using microarray technology. The assigned proportions of molecular features of ccRCC (B), pRCC (C), and chRCC (D) were compared with the original pathological classification. According to pathology, 23 tumors had a mixed histology dominated either by clear cell morphology (n = 11) or by papillary features (n = 12). Additionally, 4 ccRCC, 48 pRCC including 18 pRCC T1 and 14 pRCC T2, and 17 chRCC were analyzed. Tumors with PSA values ≥ 95% are colored. Samples with \({P}_{psa}>0.05\) are marked in gray. Boxes refer to median and interquartile ranges with whiskers extending to a maximum of 1.5 times the interquartile range