Cervical punch biopsy specimens or brushings were collected from 33 patients with cervical human papilloma virus (HPV) infection, cervical intraepithelial neoplasia (CIN), or invasive cervical carcinoma, and from eight control patients with recent normal cervical cytology. Prostatic chippings obtained from six men with benign prostatic hypertrophy were used as further controls. Biopsy specimens and brushings were assayed by flow cytometry for c-myc oncogene antigen and papillomavirus antigen expression and rate of cell division (by measuring DNA content). Results obtained from analysis of specimens and brushings were similar in terms of c-myc antigen and total DNA content, but when the percentages of nuclei from biopsy and brush specimens staining positively with antibody to papilloma viral antigens were compared, brush specimens gave consistently higher percentages than biopsy specimens. More specimens from normal epithelium were c-myc antigen positive (five of eight, (63%) than specimens from CIN II or III (two of 10, 20%), or invasive carcinoma (0%). No association was found between c-myc antigen expression and cell division. HPV antigen positive specimens were found to contain more dividing cells than negative specimens.