PTGS2 and adenosquamous carcinoma: Similarly, higher tumour/stroma COX-2 IDV ratio was found in stage III-IV with respect to stage I–II cases (P value=0.09), in adenocarcinoma and adenosquamous carcinoma versus squamous cell (P value=0.0005), in tumours ⩾4 cm vs smaller tumours (P value=0.011).