Human papillomavirus 16 DNA in cervical cancers and in lymph nodes of cervical cancer patients: a diagnostic marker for early metastases?

Human papillomavirus (HPV) 16 is most prevalent in cervical cancers and also persists in metastases. We examined HPV16-DNA-positive primary cancers and several lymph nodes from each of 14 patients to evaluate the use of HPV16 DNA as a diagnostic marker for the detection of early node involvement. The HPV16 DNA was exclusively integrated in 39% of the primary cancers, predominantly episomal in 36%, and integrated and extrachromosomal to a similar extent in 25%. Thirteen of 16 involved lymph nodes contained HPV16 sequences. Integrated viral DNA showed the same pattern in primary tumors and in metastases. The level of extrachromosomal HPV16 DNA, however, appeared to be considerably reduced in some nodes. HPV16 DNA was also detected in 18 out of 59 histologically negative lymph nodes. This result recommends nucleic acid hybridization as a sensitive method for the detection of HPV-DNA-positive cancer cells. The prognostic significance of viral sequences in histologically negative nodes remains to be established.