AKR1C1 and squamous cell carcinoma: Low AKR1C1 expression was more frequently observed in undifferentiated non‐keratinized carcinoma (UDC), T3‐T4, N2‐N3, M1 and stage III‐IV tumours than in differentiated non‐keratinized squamous carcinoma (DNKC), T1‐T2, N0‐N1, M0 and stage I‐II tumours (Figure 2A and 2B, Table 2).