BACKGROUND
Human papillomavirus (HPV) infection can be detected by in situ hybridization (ISH), in which a punctate signal pattern indicates integrated HPV DNA and a diffuse pattern denotes the presence of episomal viral DNA. This study was conducted to evaluate the usefulness of an HPV ISH assay for invasive cervical cancer.
METHODS
The HPV ISH assay for high-risk HPV and immunohistochemical staining for p16(INK4a), p53, bcl-2, and Ki-67 were performed in a tissue microarray of 279 cervical cancers.
RESULTS
High-risk HPV ISH was positive in 194 (69.5%) of the samples. Punctate, diffuse, and mixed signal patterns were observed in 157 (56.3%), one (0.4%), and 36 cases (12.9%), respectively. Positive results in high-risk HPV ISH were associated with p16 and bcl-2 expression (p = 0.01 and p < 0.01, respectively). According to a Cox regression analysis, HPV infection and its surrogate immunohistochemical markers such as p16, bcl-2, and Ki-67 were not independent prognostic factors, but stage and grade were independent prognostic factors.
CONCLUSIONS
Our results confirm that an HPV ISH assay is reasonably sensitive for HPV infection and that it might be useful to identify integrated HPV DNA in formalin-fixed and paraffin-embedded specimens. Further study encompassing HPV type, E2/E6 ratio, and therapeutic modality is necessary to understand the clinical meaning of HPV status in cervical cancer.