ERBB2 and cancer: Pearson correlation of KRT5, KRT20, ERBB2, BIRC5, and CD68 mRNA levels with clinical variables such as performance status (PS), age, sex, body mass index (BMI), presence of carcinoma in situ (Cis), tumor stage (T-prim), and WHO Grade 1973 (G-prim) levels in the larger PCR cohort (Figure 5a) revealed that luminal tumors determined by KRT20 mRNA were negatively associated with the presence of Cis and positively associated with higher age and male gender.