Histology report
Microscopy: The sections show fragments of tissue some with the surface stratified squamous mucosa, deep to which there is an infiltrate of severely pleomorphic epithelial cells with very frequent mitoses and a high nuclear to cytoplasmic ratio, showing no evidence of gland formation. There is moderately extensive necrosis of the tumour. Koilocytic atypia and squamous epithelial dysplasia is not seen in the overlying squamous epithelium. Immunoperoxidase shows that the tumour cells are strongly reactive with cytokeratin 7, p63 and 40 and do not react with cytokeratin 20, S-100, or CD45.
Macroscopy: Labelled "Anal lesions". 6 ragged fragments of haemorrhagic, pale grey ragged, friable mucosal tissue and skin ranging from 7 mm to 18 x 8 x 7 mm. The largest fragment has a smooth pale grey mucosal surface.
Conclusion: Anal tumour - poorly differentiated squamous cell carcinoma.