Biology of anogenital neoplasia

Human papillomavirus: burden of illness and treatment cost considerations

The monetary and personal costs to society of human papillomavirus (HPV) infection are enormous. In order to make a comparison of different treatment methods we reviewed the entire literature on HPV treatment from January 1966 to December 2003 using MEDLINE, with particular reference to published meta-analyses, randomized controlled and comparative studies. Patient-applied therapies offer patients the possibility of convenient and, on the whole, pain-free treatment. Podofilox (podophyllotoxin) and salicylic acid for genital and extragenital warts, respectively, have the additional advantage of being the most cost-effective treatments and, on this basis, they are to be commended as appropriate first-line agents. The second-line treatment of choice for common warts is cryotherapy. For recalcitrant common warts possible options include inosine pranobex with cryotherapy or electrosurgery, imiquimod with paring and occlusion, intralesional bleomycin, or diphencyprone. Alternative first-line and second-line treatments for genital warts would be either some form of surgical removal or imiquimod. The first option may be the cheapest but this has to be balanced against a degree of post-operative morbidity. Limited data from comparative studies do not show any clear difference in efficacy between cryotherapy, trichloroacetic acid, scissor excision, electrosurgery, and laser surgery in the treatment of genital warts, and the cost effectiveness of these therapies is probably similar to that of imiquimod. Cryotherapy and trichloroacetic acid are relatively expensive and inconvenient for patients and should be reserved as third-line treatments with certain exceptions, such as cryotherapy for meatal warts. The duration of treatment is significantly related to the number of warts present, the area covered by the warts, and the length of time the warts have been present. For recalcitrant anogenital warts third-line treatment options that show promise include surgery in combination with imiquimod or cidofovir cream. For squamous intraepithelial lesions that cannot easily be excised or physically ablated current treatment options include imiquimod and fluorouracil cream. The latter is an inexpensive option but causes the greatest morbidity. It is hoped that cidofovir may be added to this list if it becomes commercially available, and that protective and therapeutic HPV vaccines will transform the management of HPV in the future.

Host Genetic Polymorphism Analysis in Cervical Cancer

Background: The natural history of cervical cancer comprises a latency period that probably involves long-term immunologic tolerance of human papillomavirus infection. Identifying host determinants of viral persistence may help to better understand the mechanisms of tolerance and may lead to the development of tests that can allow more focused follow-up of high-risk individuals.

Methods: Genotypic frequencies of 12 polymorphic loci in four candidate genes from 127 cervical cancer patients were compared with a control group of 108 female blood donors. Genotypes were determined by PCR amplification and direct sequencing of isolated genomic DNA.

Results: The tumor necrosis factor-α (TNFα) −238 polymorphism was significantly underrepresented in cervical cancer patients [heterozygotes (HETs), odds ratio (OR) = 0.33; 95% confidence interval (CI), 0.11–0.96], as was the TNFα −376 polymorphism (P = 0.02; 0% for any variant genotype in cases vs 4.7% in controls). The NRAMP1 3′ untranslated region STP+86 polymorphism also appeared to be inversely associated with cervical cancer, but this result did not reach statistical significance (HET, OR = 0.57; 95% CI, 0.32–1.02). The p53 codon 72 arginine allele showed a suggestive negative association with cervical cancer (HET, OR = 0.49; 95% CI, 0.14–1.63; homozygotes, OR = 0.35; 95% CI, 0.11–1.17). The remaining alleles tested showed no association with cervical cancer.

Conclusions: We identified host genetic polymorphisms that may be associated with cervical cancer risk, some of which have been linked to potential functional effects on cellular immune responses or antigen processing. We failed to confirm earlier reports of increased cervical cancer susceptibility in women who harbor the p53 P72R allele. Although our findings support the general hypothesis that host immunogenetic determinants other than class II MHC may be important in the development of cervical cancer, further analysis of the HLA gene cluster comprising the implicated TNFα single-nucleotide polymorphisms will be required to determine whether their association is linkage independent.