In immunohistochemistry, only K7/K20 immunohistochemical staining pattern cannot entirely rule out poorly differentiated primary colorectal cancers, although the majority of primary colorectal cancers present K7‐negative/K20‐positive pattern (65.8%) and the minority of it present K7‐positive/K20‐negative pattern (2%) like the present case.5 The gene discussed is KRT7; the disease is colorectal cancer.