Polyomavirus infection and urothelial carcinoma.

INTRODUCTION

Polyomavirus infections are common in the general (adult) population with a reported prevalence of more than 80%. Polyomavirus can infect urothelial carcinoma and change the morphology of these malignant cells, as is shown in this paper.

MATERIAL AND METHODS

An eighty year old Hispanic male was referred to the urology clinic for diagnosis and treatment. The submitted voided urine sample was concentrated, processed, and a SurePath preparation was made.

RESULTS AND DISCUSSION

The Papanicolaou-stained slides contained single cells with very large hyperchromatic nuclei with a glassy appearance in addition to atypical neoplastic cells. The single cells with enlarged nuclei proved to stain positive for Simian virus 40 (SV40) antigen. The nuclei of these cells were 2 to 4 times larger than that of the surrounding noninfected atypical cells. These findings were confirmed on histologic sections prepared from tissue biopsy.

CONCLUSION

In conclusion we report that it is difficult to distinguish benign polyomavirus infected cells from their malignant counterparts in cytology but not in histology.