Epidemiology of Human Papillomaviruses

Rarity of Human Papillomavirus in Nonmelanoma Skin Cancer among Immunocompetent Patients

Background:

The role of human papillomavirus (HPV) in nonmelanoma skin cancer (NMSC) among immunocompentent individuals is not well understood.

Objective:

We tested for the presence of HPV DNA in NMSC of immunocompetent patients from New England.

Methods:

Biopsies taken from 59 patients were reviewed histopathologically. A segment of the biopsy and scrapings from a site remote from the skin lesion were analyzed for HPV using a standardized polymerase chain reaction (PCR) DNA amplification assay.

Results:

Of 55 evaluable samples, 21 were histologically confirmed squamous cell carcinomas (SCC), 25 were basal cell carcinomas (BCC), and nine had other diagnoses. Two samples were HPV-positive (3.6%): a basal cell carcinoma of the forehead and a squamous cell carcinoma of the thumbnail bed. Type analysis of these samples revealed HPV 16 from both lesions.

Conclusion:

The HPV DNA is not commonly detected in NMSCs of immunocompetent patients using standard laboratory techniques. It is possible, however, that a wider range of HPV types could be detected using more sensitive assays; this warrants further investigation.

Warts, malnutrition, and sunshine

Viral warts are common in poor rural settings but their relationship to malnutrition has not been studied. We sought to determine the prevalence of warts in children of two communities in Oaxaca, Mexico, and compared it with their nutritional status. Children from Santa Catarina Yahuio and Santiago Laxopa of the state of Oaxaca were examined. Localization, number, and type of verruca were noted. Date of birth, height, and weight were obtained to determine nutritional status. A total of 213 children (116 girls and 97 boys), 107 in Yahuio and 106 in Laxopa, were studied. Mean age was 10.24 years. Thirty children (14.1%) had warts and 80% (24/30) of these lived in Yahuio (p = 0.0002). Almost half were teenagers. Most lesions were on sun-exposed areas. First degree malnutrition was found in 24.5%; second degree in 23.6% and third degree in 14.2%. A higher frequency of warts than previously reported was found. Malnutrition was prevalent in both groups but did not correlate positively with verruca. Verruca were more frequent in females, adolescents, sun-exposed areas, and higher altitude. We believe that the higher altitude of Yahuio facilitates greater exposure to ultraviolet light-induced immune suppression.

Infectious Agents

There is substantial evidence that infectious agents play a causal role in a variety of human malignancies. These cancers include the liver, cervix, stomach, nasopharynx, bladder, and bile duct as well as Kaposi sarcoma (KS) and several lymphomas. This chapter summarizes the biological and epidemiologic features of each of the major oncogenic infections, beginning with the viruses, followed by H. pylori, and with a brief summary of the relevant parasites.

Secondary malignancies after hematopoietic stem cell transplantation

Advances in the field of hematopoietic stem cell transplantation have led to an increasing number of cures of malignant and non-malignant diseases with this therapeutic approach. Long-term survivorship may, however, be associated with secondary malignancies, the result of a complex interaction of treatment-, recipient- and immunosuppression-related factors. Furthermore, the increasing use of donors other than human leukocyte antigen-identical siblings is associated with more intense immunosuppression, delayed immune recovery and higher incidence of B-cell post-transplantation lymphoproliferative disorders. Here, we review the incidence and the risk factors associated with these complications of hematopoietic stem cell transplants.

Determinants of genital wart case detection rates among STD clinic attendees in Athens, Greece

BACKGROUND AND OBJECTIVE

To report significant sociodemographic and behavioral outpatient characteristics associated with the diagnosis of genital warts.

METHODS

Cross-sectional hospital-based study (1990-96).

RESULTS

Genital warts (n = 2988, 51.2%) represent the leading sexually transmitted disease (STD) among 5831 consecutive symptomatic Greek and foreign immigrant STD outpatients. In Greek heterosexuals a low rate of partner change was the main patient characteristic at diagnosis (median: one partner in the past 6 months). Lower detection rate and riskier behavior characterized immigrants. Although associated with risky behavior, homo/bisexual orientation in males and injecting drug use were not significantly associated with condyloma diagnosis in the context of STDs.

CONCLUSION

Broader health education and secondary prevention are needed to control this infection, whereas low-risk behavior in Greek heterosexuals with condylomata facilitates further preventive interventions.

Solid tumors after hematopoietic stem cell transplantation in Japan: incidence, risk factors and prognosis

To evaluate the incidence, risk factors and prognosis for solid tumors after hematopoietic stem cell transplantation (HSCT) in Japan, 809 patients who had received HSCT between 1981 and 2000 were retrospectively analyzed. In all, 19 newly diagnosed secondary cancers were observed. The risk for cancer development was 2.8 times as high as that for expected cases. The cumulative incidence ratios at 5 and 10 years were 1.9 and 4.2%, respectively. The risk was significantly elevated for buccal cavity cancer (standard incidental ratio (SIR), 44.42: 95% confidence interval (CI) 17.86-91.51), esophageal cancer (SIR, 22.36: 95% CI 6.09-57.25), and cervical cancer (SIR, 8.58: 95% CI 1.04-31.01). Of 15 patients who developed solid cancers following allografting, 12 had chronic graft-versus-host disease (GVHD), and all 10 patients with squamous cell carcinoma of the buccal cavity or esophagus had chronic GVHD. On multivariate analysis, extensive chronic GVHD and age over 45 years at the time of transplantation were associated with a higher risk for solid cancers. In all, 17 patients received therapy for secondary cancers, nine of whom are still alive and the 5-year probability of survival from the diagnosis is 42.8%. Our data suggest that early detection of secondary cancers is very important in prolonging overall survival.

Human papillomaviruses in the normal oral cavity of children in Japan

The purpose of this study was to determine the frequency of human papillomavirus (HPV) infections in the normal oral cavity of children in Japan. Oral squamous cell specimens were collected from 77 children (44 boys and 33 girls), aged 3 and 5 years. Extracted DNA was evaluated for HPV infections by polymerase chain reaction (PCR) methods, using consensus primers for the L1 region, specific primers, and direct DNA sequencing analysis. Thirty-seven of 77 specimens (48.1%) were positive for HPV DNA. Positive rates of boys and girls in all specimens were 28.3 (22/77) and 19.5 (15/77)%, respectively. The positive rate in 3-year-old children was 45.2 (14/31)%, and positive rates in boys and girls were 52.6 (10/19) and 33.3 (4/12)%, respectively. The positive rate in 5-year-old children was 50.0 (23/46)%, and positive rates in boys and girls were 48.0 (12/25) and 52.4 (11/21)%, respectively. HPV types were determined by specific PCR and direct DNA sequencing analysis. Frequent HPV types in the specimens of all children were HPV-16 (11/37; 29.7%),-1 (6/37; 16.2%),-2 (6/37; 16.2%),-75 (6/37; 16.2%). The results of the present investigation indicate that many HPVs, including HPV-16 (a high-risk type for cancer), are present in the oral cavity of 3- and 5-year-old children. It is suggested, therefore, that the oral cavity is already a reservoir of HPVs in childhood where later HPV-associated diseases, such as oral cancer and other oral lesions, may develop.

Solid cancers after bone marrow transplantation

PURPOSE

To evaluate the incidence and associated risk factors of solid cancers after bone marrow transplantation (BMT).

PATIENTS AND METHODS

We analyzed 2,129 patients who had undergone BMT for hematologic malignancies at the City of Hope National Medical Center between 1976 and 1998. A retrospective cohort and nested case-control study design were used to evaluate the role of pretransplantation therapeutic exposures and transplant conditioning regimens.

RESULTS

Twenty-nine patients developed solid cancers after BMT, which represents a two-fold increase in risk compared with a comparable normal population. The estimated cumulative probability (+/- SE) for development of a solid cancer was 6.1% +/- 1.6% at 10 years. The risk was significantly elevated for liver cancer (standardized incidence ratio [SIR], 27.7; 95% confidence interval [CI], 1.9 to 57.3), cancer of the oral cavity (SIR, 17.4; 95% CI, 6.3 to 34.1), and cervical cancer (SIR, 13.3; 95% CI, 3.5 to 29.6). Each of the two patients with liver cancer had a history of chronic hepatitis C infection. All six patients with squamous cell carcinoma of the skin had chronic graft-versus-host disease. The risk was significantly higher for survivors who were younger than 34 years of age at time of BMT (SIR, 5.3; 95% CI, 2.7 to 8.6). Cancers of the thyroid gland, liver, and oral cavity occurred primarily among patients who received total-body irradiation.

CONCLUSION

The risk of radiation-associated solid tumor development after BMT is likely to increase with longer follow-up. This underscores the importance of close monitoring of patients who undergo BMT.

Human papillomavirus in the oral cavities of children and adolescents

OBJECTIVE

The purpose of this pilot study was to determine the frequency of human papillomavirus (HPV) in the oral cavities of children and adolescents and to identify potential risk factors for HPV infection.

STUDY DESIGN

Sociodemographic information was obtained on 268 healthy infants, children, and adolescents who were < or = 20 years old. Oral squamous cells were collected from swabs with young children and from oral saline solution rinses with older children and adolescents. Extracted DNA was evaluated for HPV by polymerase chain reaction, dot blot hybridization, and DNA sequencing. Factors associated with the presence of HPV were tested by using chi(2), Fisher's exact test, and logistic regression tests.

RESULTS

HPV was detected in 6.0% of the participants. HPV frequency among young children (<7 years old) was 8.7% (11/127), and among adolescents (13-20 years old) it was 5.2% (5/97). HPV was not detected in children aged 7 to 12 years old (0/44). Fifty-four percent (6/11) of HPV-positive children were 1 year of age or less; 3 of the HPV-positive children (<7 years old) were delivered by cesarean section. No statistically significant association was found between the detection of HPV in the oral cavity and method of delivery or gender; parent's race, education, HPV-related conditions, smoking history, or number of sex partners; or adolescent's smoking history or history of sexual activity.

CONCLUSIONS

This study suggests that HPV is present in the oral cavity primarily in children 2 years old and younger and in adolescents 13 years and older. Cesarean delivery was not protective against oral HPV infection; in fact, half of the HPV-positive infants were born by cesarean delivery.

Self-administered topical 5% imiquimod for the treatment of common warts and molluscum contagiosum

BACKGROUND

Despite numerous therapeutic options the treatment of common warts and molluscum contagiosum remains unsatisfactory for both patients and physicians. Imiquimod, a novel topical immune response modifier, has been successfully used for the treatment of external anogenital warts.

OBJECTIVES

We aimed to evaluate the safety, tolerance and efficacy of imiquimod for the treatment of common cutaneous warts and mollusca that were resistant to previous therapeutic interventions.

METHODS

Imiquimod 5% cream was self-applied by the patients to the warts or mollusca once daily for 5 days per week and left in place overnight. Assessment for response and the occurrence of side-effects was performed every 4 weeks until clinical cure or up to a maximum of 16 weeks.

RESULTS

Twenty-eight of 50 (56%) patients with warts achieved a total clearance (n = 15; 30%) or a > 50% reduction in wart size (n = 13; 26%) after a mean treatment period of 9.2 weeks. Twelve of 15 (80%) patients with mollusca achieved a total clearance (n = 8; 53%) or a > 50% reduction in molluscum size (n = 4; 27%). There was no difference in response with regard to gender, human immunodeficiency virus serostatus or atopic predisposition.

CONCLUSIONS

Patient-applied 5% imiquimod cream holds promise as an effective treatment of common warts and mollusca in a difficult-to-treat patient population.

[Does a particular risk associated with papillomavirus infections exist in women with lupus?]

PURPOSE

There is strong evidence that papillomavirus infections (HPV), especially infections with HPV 16/18, are involved in the development of dysplasia and cancers. Cervical cancer is thought to be increased in women with systemic lupus erythematosus (SLE).

METHODS

To assess this risk we studied cervical smears from 11 women with SLE and determined the prevalence of HPV infection by in situ hybridization.

RESULTS

Dysplasia was found in 9% of women with SLE and in 0.03% of control subjects (non significant difference). Dysplasia was found to be six times more frequent in women with SLE (18% versus 3%, P < 0.01). HPV prevalence in normal smears was 37.5% in women with SLE versus 14.7% in control subjects (non-significant difference). Identified HPV genotypes were those for which intermediate or high risk is well established. No correlation was found between infection or dysplasia risk and the lymphocyte count or a previous treatment with cyclophosphamide.

CONCLUSION

We conclude that women with SLE would be at increased risk of HPV infection, dysplasia and cervical cancer. We suggest that women with SLE should be regularly tested for cervical cancer by colposcopy, especially in case of HPV 16 infection.

Trends in seroprevalence of human papillomavirus type 16 among pregnant women in Stockholm, Sweden, during 1969-1989

To assess long-term trends in the prevalence of oncogenic human papillomavirus (HPV) infection, we performed a cross-sectional serosurvey of the seroprevalence of the major oncogenic HPV type, HPV16, among 3,512 pregnant women undergoing population-based serological screening at the first trimester of pregnancy in the same catchment area in Stockholm, Sweden, during 1969, 1983 or 1989. The overall HPV16 seroprevalence rates were 16% in 1969, 22% in 1983 and 21% in 1989. Seroprevalence was significantly increased, comparing both 1969 vs. 1983 (p = 0.0005) and 1969 vs. 1989 (p = 0.008). By comparison, the previously reported herpes simplex 2 (HSV-2) seroprevalence in the same women increased from 17% in 1969 to 32% in 1983 and 33% in 1989, whereas the seroprevalence rates of HSV-1 were the same (69% in 1969, 63% in 1983 and 68% in 1989). Odds ratios for HPV 16-positive women to also be HSV-2-positive were 1.8 in 1969 (p < 0.005), 1.1 in 1983 (p = NS) and 1.0 in 1989. Our results suggest that both HSV-2 and HPV16 became more generally spread in the Swedish population between 1969 and 1983 but that the spread has been stable during the 1980s.

Solid cancers after bone marrow transplantation

BACKGROUND

The late effects of bone marrow transplantation, including cancer, need to be determined in a large population at risk.

METHODS

We studied 19,229 patients who received allogeneic transplants (97.2 percent) or syngeneic transplants (2.8 percent) between 1964 and 1992 at 235 centers to evaluate the risk of the development of a new solid cancer. Risk factors relating to the patient, the transplant, and the course after transplantation were evaluated.

RESULTS

The transplant recipients were at significantly higher risk of new solid cancers than the general population (observed cases, 80; ratio of observed to expected cases, 2.7; P<0.001). The risk was 8.3 times higher than expected among those who survived 10 or more years after transplantation. The cumulative incidence rate was 2.2 percent (95 percent confidence interval, 1.5 to 3.0 percent) at 10 years and 6.7 percent (95 percent confidence interval, 3.7 to 9.6 percent) at 15 years. The risk was significantly elevated (P<0.05) for malignant melanoma (ratio of observed to expected cases, 5.0) and cancers of the buccal cavity (11.1), liver (7.5), brain or other parts of the central nervous system (7.6), thyroid (6.6), bone (13.4), and connective tissue (8.0). The risk was higher for recipients who were younger at the time of transplantation than for those who were older (P for trend <0.001). In multivariate analyses, higher doses of total-body irradiation were associated with a higher risk of solid cancers. Chronic graft-versus-host disease and male sex were strongly linked with an excess risk of squamous-cell cancers of the buccal cavity and skin.

CONCLUSIONS

Patients undergoing bone marrow transplantation have an increased risk of new solid cancers later in life. The trend toward an increased risk over time after transplantation and the greater risk among younger patients indicate the need for life-long surveillance.