HPV in anal squamous cell carcinoma and anal intraepithelial neoplasia (AIN). Impact of HPV analysis of anal lesions on diagnosis and prognosis

HPV-independent Vulvar Squamous Cell Carcinoma is Associated With Significantly Worse Prognosis Compared With HPV-associated Tumors

Vulvar squamous cell carcinomas (VSCC) represent the most common carcinoma of the female external genitalia, with increasing incidence. Although high-risk human papillomavirus (HPV) infection has long been implicated in the majority of cervical and anal squamous cell carcinomas, there is uncertainty about its prevalence and prognostic impact in VSCC. In this study, we conducted a retrospective integrated morphologic and multimodal HPV analysis of a cohort of 114 VSCC cases treated at the Princess Margaret Cancer Centre/University Health Network, Toronto, Canada between 2000 and 2010. VSCC histology was reviewed. We analyzed the cohort for HPV using polymerase chain reaction based method, and tissue microarray DNA and RNA in situ hybridization (ISH), and p16 immunohistochemistry. Among the 114 cases (age 70±16 yr), 36.7% of cases were classified as having histomorphology of HPV infection. HPV was detected in 31.9% (polymerase chain reaction), 14.0% (DNA ISH), and 27.3% (RNA ISH) of cases. p16 immunohistochemistry was positive in 37.8% of cases. On univariate analysis, HPV morphology (P=0.009), p16+ (P=0.00013), DNA ISH+ (P=0.021), and RNA ISH+ (P=0.00061) were associated with better 5-yr progression-free survival. DNA ISH+ (P=0.049) was associated with better 5-yr overall survival. On multivariate analysis, HPV morphology (P=0.033), p16+ (P=0.01), and RNA ISH+ (P=0.035) were associated with better 5-yr progression-free survival. In conclusion, a subset of VSCC is associated with HPV, which correlates with better outcome. Relatively inexpensive tests such as histomorphologic evaluation, p16 immunohistochemistry, and HPV RNA ISH can be used to predict outcome in VSCC. Therefore, routine reporting of HPV status in VSCC is recommended.

Clinicopathological aspects and prevalence of human papillomavirus in anal cancer

Anal cancer is relatively rare; however, its incidence has increased in recent years. Several risk factors are associated with the development of anal cancer, including age older than 50 years, low-fiber diet, chronic anal fistulas, smoking, multiple partners, anal intercourse practice, Human Immunodeficiency Virus infection and immunosuppression. However, the presence of human papillomavirus represents the main risk factor for the development of anal cancer. The aim of this study was to evaluate the clinicopathological aspects of a series of patients with anal carcinomas diagnosed in Hospital Araújo Jorge, Goiânia-Goiás, as well as the prevalence of human papillomavirus genome in these tumors. Clinical, pathological and socio-demographic data were collected from the respective medical files and paraffin blocks containing anal carcinomas specimens were used for DNA extraction and detection of human papillomavirus, by means of polymerase chain reaction, using short PCR fragment primers. Forty-three cases were selected and had the data analyzed, while 38 cases were tested for human papillomavirus genome detection. Among the evaluated patients, 62.8% were women; 53.4% of tumors were squamous cell carcinoma and 46.5% of the patients were aged between 60 and 75 years. Risk factors, such as smoking (39.5%) and alcoholism (20.9%) were recorded in the studied group. Lymph node metastases were detected in 30.2% of cases and 7.0% had distant metastasis. The detection of human papillomavirus DNA was positive in 76% of cases assessed and this was significantly associated with squamous cell carcinomas. Aggressive behavior and advanced stage of anal cancer described in this study highlight the need for preventive measures that contemplate these tumors, including vaccination against human papillomavirus.

Co-presence of human papillomaviruses and Epstein-Barr virus is linked with advanced tumor stage: a tissue microarray study in head and neck cancer patients

Background

Human papillomaviruses (HPVs) and Epstein–Barr virus (EBV), known oncoviruses, can be co-present and cooperate in the initiation and/or progression of human carcinomas, including head and neck. Based on this fact, we recently reported the prevalence of both HPVs and EBV in cervical and breast cancers.

Methods

We herein explore for the first time the co-prevalence of high-risk HPVs and EBV in 98 head and neck (HN) squamous cell carcinoma (SCC) tissues from Bosnian patients using polymerase chain reaction (PCR) and immunohistochemistry (IHC) analysis, as well as tissue microarray methodology.

Results

The majority of these cancer tissue cases were from the oral cavity (68%). We found that high-risk HPVs and EBV are co-present in 34.7% of the SCC samples; with a significant correlation between the various HPV types and EBV co-incidence (p = 0.03). Our data showed that 30.8% of oral SCCs are positive for E6 oncoprotein of high-risk HPVs and 44.6% are positive for LMP1 of EBV. The most commonly expressed HPVs in our HNSCC samples include HPV types 16, 18, 45 and 58. Additionally, 37.5% of oral SCCs are positive for both HPVs and EBV, with statistically significant association between high-risk HPV types and EBV (p < 0.05). More importantly, our data revealed that the co-presence of HPV and EBV is strongly correlated with advanced tumor stage (p = 0.035).

Conclusion

In this study we show that HPV and EBV oncoviruses are co-present in HNSCC, particularly in oral cancer, where they can cooperate in the initiation and/or progression of this cancer. Thus, further studies are necessary to elucidate the mechanism of this cooperation.

Human Papillomavirus and Anal Cancer: Prevalence, Genotype Distribution, and Prognosis Aspects from Midwestern Region of Brazil

BACKGROUND

Approximately 90% of all anal cancers are associated with human papillomavirus (HPV), especially high-risk genotypes such as HPVs 16 and 18.

OBJECTIVE

To investigate the clinical and prognostic aspects of anal cancers associated with the presence, as well as the genotypic distribution of human papillomavirus (HPV).

METHODS

A retrospective study carried out over a 10-year period, using clinical and molecular data, with PCR analysis and reverse hybridization (INNO-LIPA kit), in anal cancers. The data analysis was done using descriptive univariate statistics, and the survival curves were made using the Kaplan-Meier and log-rank methods.

RESULTS

Of the 81 formalin-fixed and paraffin-embedded specimens, HPV prevalence was 69% and was significantly higher in squamous cell carcinomas (SCC) than in other anal tumors (p=0.0001). Female patients had a higher prevalence of HPV (p=0.01). Multiple infections were detected in 14.3% of cases. The most prevalent genotypes were HPVs 16, 33, and 18. The overall survival at 60 months was 44.3%, and the prognostic factors included gender (p=0.008) with greater survival for men (52.9%) in comparison to women (29.6%), histological type (p=0.01), SCC (54.4%), adenocarcinomas (37.5%), other carcinomas (14.2%), and the presence of distant metastasis (p=0.01). Survival was not influenced by the presence of HPV (p=0.54).

CONCLUSIONS

The association of HPV to anal cancer was found in this study, especially in SCC. However, the presence of HPV did not influence the prognosis of patients with anal cancer.

Human papillomavirus in ocular malignant tumours: a study from a tertiary eye care centre in North India

OBJECTIVE

The present study aims to detect the presence of human papillomavirus (HPV) in ocular malignant tumours, including retinoblastoma, eyelid squamous cell carcinoma (SCC), and sebaceous gland carcinoma (SGC), in the North Indian population.

DESIGN

Prospective observational non randomized study.

PARTICIPANTS

In this study, 142 prospective cases of ocular malignant tumours (retinoblastoma, SGC, and SCC) were included.

METHODS

HPV was detected by multiplex PCR using PGMY09/11 primers in 142 patients with ocular malignancies. This was followed by genotyping using linear array (reverse hybridization).

RESULTS

Of the 142 tumours studied, 72 were retinoblastoma, 30 SGC, and 40 SCC. The HPV genome was detected in 2.8% (4 of 142) of cases by multiplex PCR; all positive cases (4 of 40) were SCC. Genotyping revealed that all positives belonged to the high-risk HPV16 genotype. HPV-positive SCC patients had better disease-free survival. Retinoblastoma and SGC cases were negative for HPV.

CONCLUSIONS

Low prevalence of HPV in ocular malignancies was observed in this study. The HPV genome was detected only in ocular squamous cell carcinoma cases and these patients were associated with better prognosis. HPV may not have a role in retinoblastoma and SGC in the North Indian population.

Liver transplant recipients have a higher prevalence of anal squamous intraepithelial lesions

BACKGROUND

Anal squamous intraepithelial lesions (ASIL) are precancerous lesions of anal squamous cell carcinoma, with a higher prevalence in immunosuppressed patients. There are some studies in kidney transplant recipients, but there is no information regarding prevalence in liver transplantation. Our aim was to evaluate the prevalence of ASIL in this setting.

METHODS

Prospective case-control study involving liver transplant recipients without any other known risk factor for ASIL (n=59), which were compared with a healthy control group (n=57). All were submitted to anal cytology and high-resolution anoscopy was performed in those with abnormal results.

RESULTS

Ten (17%) of liver transplant recipients had abnormal cytological results, seven patients had atypical squamous cells of undetermined significance (ASC-US), one patient had atypical squamous cells that cannot exclude high-grade (ASC-H) and two patients had high-grade squamous intraepithelial lesions (HSIL). In the control group, one patient (2%) had an ASC-US result (P=0.005). Anal squamous intraepithelial lesions were confirmed in 7 out of 10 of liver transplant patients and 0 out of 1 in the controls (P=0.013) by high-resolution anoscopy with biopsies. Current smoking was the only risk factor for abnormal cytology (odds ratio=5.87, 95% confidence intervals=1.22-28.12, P=0.027).

CONCLUSIONS

Liver transplant patients have a higher risk of ASIL. Screening should be considered, especially in smokers.

The economic burden of human papillomavirus-related precancers and cancers in Sweden

Background

High-risk (HR) human papillomavirus (HPV) infection is an established cause of malignant disease. We used a societal perspective to estimate the cost of HR HPV-related cervical, vulvar, vaginal, anal, and penile precancer and cancer, and oropharyngeal cancer in Sweden in 2006, 1 year before HPV vaccination became available in the country.

Materials and methods

This prevalence-based cost-of-illness study used diagnosis-specific data from national registries to determine the number of HR HPV-related precancers and cancers. The HR HPV-attributable fractions of these diseases were derived from a literature review and applied to the total burden to estimate HR HPV-attributable costs. Direct costs were based on health care utilization and indirect costs on loss of productivity due to morbidity (i.e., sick leave and early retirement) and premature mortality.

Results

The total annual cost of all HR HPV-attributable precancers and cancers was €94 million (€10.3/inhabitant). Direct costs accounted for €31.3 million (€3.4/inhabitant) of the total annual cost, and inpatient care amounted to €20.7 million of direct costs. Indirect costs made up €62.6 million (€6.9/inhabitant) of the total annual cost, and premature mortality amounted to €36 million of indirect costs. Cervical precancer and cancer was most costly (total annual cost €58.4 million). Among cancers affecting both genders, anal precancer and cancer, and oropharyngeal cancer were the most costly (€11.2 million and €11.9 million, respectively). For oropharyngeal cancer, males had the highest health care utilization and represented 71% of the total annual cost. Penile precancer and cancer was least costly (€2.6 million).

Conclusion

The economic burden of HR HPV-related precancers and cancers is substantial. The disease-related management and treatment costs we report are relevant as a point of reference for future economic evaluations investigating the overall benefits of HPV vaccination in females and males in Sweden.

Cetuximab Plus Chemoradiotherapy in Immunocompetent Patients With Anal Carcinoma: A Phase II Eastern Cooperative Oncology Group-American College of Radiology Imaging Network Cancer Research Group Trial (E3205)

Purpose Squamous cell carcinoma of the anal canal (SCCAC) is characterized by high locoregional failure (LRF) rates after sphincter-preserving definitive chemoradiation (CRT) and is typically associated with anogenital human papilloma virus infection. Because cetuximab enhances the effect of radiation therapy in human papilloma virus-associated oropharyngeal squamous cell carcinoma, we hypothesized that adding cetuximab to CRT would reduce LRF in SCCAC. Methods Sixty-one patients with stage I to III SCCAC received CRT including cisplatin, fluorouracil, and radiation therapy to the primary tumor and regional lymph nodes (45 to 54 Gy) plus eight once-weekly doses of concurrent cetuximab. The study was designed to detect at least a 50% reduction in 3-year LRF rate (one-sided α, 0.10; power 90%), assuming a 35% LRF rate from historical data. Results Poor risk features included stage III disease in 64% and male sex in 20%. The 3-year LRF rate was 23% (95% CI, 13% to 36%; one-sided P = .03) by binomial proportional estimate using the prespecified end point and 21% (95% CI, 7% to 26%) by Kaplan-Meier estimate in a post hoc analysis using methods consistent with historical data. Three-year rates were 68% (95% CI, 55% to 79%) for progression-free survival and 83% (95% CI, 71% to 91%) for overall survival. Grade 4 toxicity occurred in 32%, and 5% had treatment-associated deaths. Conclusion Although the addition of cetuximab to chemoradiation for SCCAC was associated with lower LRF rates than historical data with CRT alone, toxicity was substantial, and LRF still occurs in approximately 20%, indicating the continued need for more effective and less toxic therapies.

Cetuximab Plus Chemoradiotherapy for HIV-Associated Anal Carcinoma: A Phase II AIDS Malignancy Consortium Trial

Purpose Squamous cell carcinoma of the anal canal (SCCAC) is characterized by high locoregional failure (LRF) rates after definitive chemoradiation (CRT), associated with anogenital human papilloma virus, and often appears in HIV infection. Because cetuximab enhances the effect of radiation therapy in human papilloma virus-associated oropharyngeal SCC, we hypothesized that adding cetuximab to CRT would reduce LRF in SCCAC. Methods Forty-five patients with stage I to III SCCAC and HIV infection received CRT: 45 to 54 Gy radiation therapy to the primary tumor and regional lymph nodes plus eight once-weekly doses of concurrent cetuximab and two cycles of cisplatin and fluorouracil. The study was designed to detect at least a 50% reduction in 3-year LRF rate (one-sided α, 0.10; power, 90%), assuming a 35% LRF rate from historical data. Results The 3-year LRF rate was 42% (95% CI, 28% to 56%; one-sided P = .9) by binomial proportional estimate using the prespecified end point (LRF or alive without LRF and followed < 3 years), and 20% (95% CI, 10% to 37%) by Kaplan-Meier estimate in post hoc analysis using definitions and methods consistent with historical data. Three-year rates by Kaplan-Meier estimate were 72% (95% CI, 56% to 84%) for progression-free survival and 79% (95% CI, 63% to 89%) for overall survival. Grade 4 toxicity occurred in 26%, and 4% had treatment-associated deaths. Conclusion HIV-associated SCCAC is potentially curable with definitive CRT. Although addition of cetuximab may result in less LRF, the 20% recurrence and 26% grade 4 toxicity rates indicate the continued need for more-effective and less-toxic therapies.

Progress in the Research on the Relationship between Infection with Human Papillomavirus and Tumorigenesis

Human papillomavirus (HPV) is a DNA virus that infects the skin and mucous membranes of the human body. Approximately 80% of sexually active women are likely infected with HPV. Cervical cancer is one of the most common malignant tumors and is second in incidence only to breast cancer. Infection with high-risk HPV types is the main risk factor for cervical cancer, which is currently the only malignant tumor with a clearly defined etiology. HPV infection is also closely related to the incidence and development of other malignant tumors. In addition to cervical cancer, HPV can cause other urogenital tumors, as well as tumors in the digestive tract, lungs, eyes, skin, and other organ systems. This paper provides a review of the progress in HPV infection-related research and provides novel ideas for the study of tumor etiology and mechanisms.

Human papillomavirus (HPV) infection: a Mozambique overview

Human Papillomavirus is agent of the most common sexually transmitted disease which is able to infect mucosal and cutaneous membranes of the anogenital region, upper aerodigestive tract, and other head and neck mucosal regions. Although mainly HPV infection can be asymptomatic and transient, it may persist and give rise to various lesions such as warts, condyloma dysplasia and cancers depending on low or high risk type of HPV infection. Moreover, growing recent evidence suggests a role of this virus in male and female fertility. To date no effective prevention, test, treatment and control strategies are provided for people in developing countries despite the reported high incidence of HPV both in women and men. This paper reviews the more recent literature about HPV infection highlighting epidemiology, related pathologies and possible fertility effects of HPV in male and female with particular attention to the Mozambique context.

Human papillomaviruses-related cancers. Presence and prevention strategies in the Middle east and north African regions

Human papillomavirus (HPV) infections are estimated to be the most common sexually transmitted infections worldwide. Meanwhile, it is well established that infection by high-risk HPVs is considered the major cause of cervical cancer since more than 96% of these cancers are positive for high-risk HPVs, especially types 16 and 18. Moreover, during the last 2 decades, numerous studies pointed-out the possible involvement of high-risk HPV in several human carcinomas including head and neck, colorectal and breast cancers. The association between high-risk HPVs and cervical cancer and potentially other human malignancies would necessitate the introduction of vaccines which were generated against the 2 most frequent high-risk HPVs (types 16 and 18) worldwide, including the Middle East (ME) as well as North African countries. The presence of high-risk HPVs in the pathogenesis of human cancers in the ME, which is essential in order to evaluate the importance of vaccination against HPVs, has not been fully investigated yet. In this review, we present an overview of the existing epidemiological evidence regarding the presence of HPV in human cancers in the ME and the potential impact of vaccination against HPV infections and its outcome on human health in this region.

A Case of Rectal Squamous Cell Carcinoma with Metachronous Diffuse Large B Cell Lymphoma in an HIV-Infected Patient

Diffuse large B cell lymphoma (DLBCL) is one of the most common acquired immune deficiency syndrome (AIDS)-defining malignancies among human immunodeficiency virus-infected patients, and rectal cancer has recently emerged as a prevalent non-AIDS-defining malignancy. We report a case of rectal squamous cell carcinoma that was metachronous with DLBCL in an HIV-infected patient who was receiving highly active antiretroviral therapy. The patient was diagnosed with DLBCL and showed complete remission after chemotherapy. Follow-up imaging showed increased uptake at the rectum, previously treated as lymphoma. Repeated biopsy was performed and squamous cell carcinoma of the rectum was reported. After concurrent chemoradiation therapy, curative resection was performed.

The prognostic value of HPV status and p16 expression in patients with carcinoma of the anal canal

Background

In anal cancer studies, the detection frequency of high-risk HPV (human papillomavirus) is variable, depending on the method used. There are limited data reporting results of different HPV detection techniques in the same clinical series, and very few correlating results with clinical outcome.

Objectives

To evaluate tumor expression of p16/HPV16 using three different methods, and to determine their association with clinical outcome in patients with anal canal squamous cell carcinomas (SCC).

Design

This retrospective study included patients with anal canal SCC treated with definitive radiotherapy or chemoradiotherapy at a single institution between 1992 and 2005. Formalin-fixed paraffin–embedded tumor samples from 53 of the 89 (60%) patient pre-treatment biopsies were adequate for tissue microarray construction. HPV status was determined using: p16 expression by conventional immunohistochemistry (IHC) and quantitative IHC (AQUA), HPV genotype analysis by chromogenic in situ hybridization (CISH) and HPV linear array sub-typing. Expression status was correlated with clinical outcome.

Results

80% (28/35) of patient tumors had high p16 expression using conventional IHC. HPV16 CISH was positive in 81% (34/42) of tumors, and 78% (28/36) of tumors were HPV subtype 16. HPV16 CISH correlated with p16 evaluated by conventional IHC (correlation coefficient 0.46; p = 0.01) and by p16 AQUA score (correlation coefficient 0.49; p = 0.001). A subset of cases (15%) had very high p16 quantitative IHC scores (>244) and were associated with a higher incidence of local or distant recurrence (p = 0.04).

Conclusions

The vast majority (80%) of anal canal SCC in our series were positive for HPV16/p16, regardless of the testing method used. The exploratory analysis of automated quantitative IHC scoring was the only technique to define a subset of patients with a worse prognosis by p16 expression status on univariate analysis. Further exploration of the molecular mechanisms of treatment resistance in association with very high p16 expression is warranted.

Prognostic value of human papillomavirus in anal squamous cell carcinoma

PURPOSE

Anal cancer is an uncommon malignancy, but its incidence is increasing worldwide. Chemoradiation is the standard primary treatment for patients with loco-regional limited disease. However, once patients develop metastatic spread, the prognosis is very poor. Human papillomavirus (HPV) is present in around 80 % of anal cancers, but its prognostic and/or predictive value is essentially unknown in this disease.

METHODS

We retrospectively evaluated 50 patients with the diagnosis of anal squamous cell carcinoma treated at our institution with combined chemoradiotherapy for loco-regional limited disease. HPV status was evaluated from paraffin-embedded tumor tissues collected at the time of diagnosis by a polymerase chain reaction analysis.

RESULTS

Among 50 patients, 42 (84 %) were HPV-positive. Thirty-two (64 %) patients were positive to genotype 16, two (4 %) to genotype 18, and three (6 %) to both 16 and 18. Lymph nodal involvement and clinical stage at diagnosis were more advanced for HPV-positive patients. After a median follow-up of 4 years (range 0.4-13.8), 46 (92 %) patients were alive. Overall, eight patients relapsed: One regional, one loco-regional, and six distant recurrences were observed. Four patients died of metastatic disease. Five-year disease-free survival (DFS) in HPV-positive and HPV-negative patients was 92.5 and 50.0 %, respectively (P < 0.01). In multivariate analysis, HPV-positivity was associated with a statistically significant better 5-year DFS (HR HPV+ vs HPV- 0.10; 95 % CI 0.02-0.50). Five-year overall survival in HPV-positive and HPV-negative patients was 93.3 and 66.7 %, respectively (P = 0.12).

CONCLUSIONS

In our study, HPV-positive anal cancers had a statistically significant improved DFS compared to HPV-negative group.

High-Risk HPVs and Human Carcinomas in the Syrian Population

Human papillomavirus (HPV) infection is the most common sexually transmitted infection; persistent infection with high-risk types of HPV present a major risk factor for the initiation and progression of a variety of human carcinomas including cervical, colorectal, head, and neck (HN) as well as breast carcinomas. A huge number of studies investigated and reported the incidence of high-risk HPVs in these cancers worldwide particularly in the developed countries; therefore, two HPV prophylactic vaccines against the two most frequent high-risk HPV types (16 and 18) have been developed and used worldwide. However, there are very limited studies about the prevalence of HPVs in the developing countries especially in Africa and some states of the Middle East. In this mini review, we outline the presence of high-risk HPVs in human cervical, colorectal, HN as well as breast cancers in the Syrian population, which was recently explored for the first time by a Canadian/Syrian group.

HPV and precancerous lesions of anal canal in women: systematic review

OBJECTIVE

The infection caused by human papillomavirus (HPV) in the anogenital area is considered the most common sexually transmitted infection in the world. Although anal cancer is relatively uncommon in the general population, there has been a significant increase in incidence in recent years. In this review, we focused on research on anal lesions in women.

METHOD

Research on HPV and precancerous lesions of the anal canal was examined by a systematic literature review in the Cochrane Centre of Brazil, where 1,734 publications were identified in the databases Scielo Brazil, Pubmed, Lilac, Medline, and Old Medline, for the period 1966 to 2010. We selected two papers, published in 1994 and 2009, based on the inclusion-exclusion criteria.

RESULTS

The first paper refers to the study of the anal canal in HIV-negative women with previous genital pathology and its relationship to the presence of HPV, and the other compares two groups of women who are HIV+ and HIV- and its relationship with anal disease and HPV.

CONCLUSION

The existence of previous genital neoplasia associated with HPV promotes the development of anal lesions, especially in younger patients, and a poor immune status contributes to the appearance of this pathologic finding.

Audit of paired anal cytology and histopathology outcomes in patients referred to a public sexual health clinic

BACKGROUND

The level of agreement between anal cytology and histopathology is not clear with only a few studies evaluating the reliability of anal specimen reporting. Australian data in relation to this are limited.

METHODS

The results of paired anal cytology and histopathology specimens received between 2002 and 2008 from patients who were referred within the sexual health clinic were retrieved from the anatomical pathology database. A total of 248 paired samples from 154 (21 females, 133 males) participants were extracted. Concurrent high risk human papilloma virus (hrHPV) DNA assay and HIV status for the study group were also collected. Data were tabulated according to reported grade of squamous abnormality based on the Bethesda system. Using the biopsy result as the gold standard the specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) for cytology were calculated and the association between grade of abnormality, HIV status and hrHPV infection estimated.

RESULTS

Concordance between cytology and histology showed that in 204 (85%) paired samples both tests were categorised as abnormal (Kappa statistic 0.73, P = 0.013). The cytology result showed a sensitivity of 96%, specificity 14%, PPV 89% and NPV 31% when compared with histopathology. HrHPV assay was positive in 192 (80%) samples. High-grade squamous abnormalities were reported in biopsy specimens from 60% (n = 42/67) of HIV-positive subjects and 25% (n = 22/87) of HIV-negative subjects. HIV-positive individuals were more likely to be hrHPV positive, odds ratio (OR) 6.21 [95% confidence interval (CI) 2.69 to 14.34], when compared with HIV-negative subjects.

CONCLUSION

Anal cytology is highly sensitive for the detection of abnormal squamous cells. While cytology has low specificity for predicting the grade of abnormality compared with biopsy outcome, its application as a screening method in asymptomatic at risk populations warrants further study.

Episomal and integrated human papillomavirus type 16 loads and anal intraepithelial neoplasia in HIV-seropositive men

OBJECTIVES

To assess levels of episomal and integrated human papillomavirus type 16 (HPV-16) loads in HIV-seropositive men who have sex with men (MSM) in anal infection and to study the association between episomal and integrated HPV-16 loads and anal intraepithelial neoplasia (AIN).

STUDY DESIGN

A cohort study of 247 HIV-positive MSM followed each 6 months for 3 years. Overall, 135 (54.7%) men provided 665 HPV-16-positive anal samples.

METHODS

Episomal and integrated HPV-16 loads were measured with quantitative real-time PCR assays. HPV-16 integration was confirmed in samples with a HPV-16 E6/E2 of 1.5 or more with PCR sequencing to demonstrate the presence of viral-cellular junctions.

RESULTS

The HPV-16 DNA forms in anal samples were characterized as episomal only in 627 samples (94.3%), mixed in 22 samples (3.3%) and integrated only in nine samples (1.4%). HPV-16 episomal load [odds ratio (OR) = 1.5, 95% confidence interval (CI) 1.1-2.1], number of HPV types (OR = 1.4, 95% CI 1.1-1.8) and current smoking (OR = 4.8, 95% CI 1.3-18.6) were associated with high-grade AIN (AIN-2,3) after adjusting for age and CD4 cell counts. Integrated HPV-16 load was not associated with AIN-2,3 (OR = 0.7, 95% CI 0.4-1.1). Considering men with AIN-1 at baseline, four (16.7%) of the 24 men who progressed to AIN-2,3 had at least one sample with integrated HPV-16 DNA compared with three (23.1%) of 13 men who did not progress (OR = 0.7, 95% CI 0.2-3.8; P = 0.64). Integration was detected in similar proportions in samples from men without AIN, with AIN-1 or AIN-2,3.

CONCLUSION

High episomal HPV-16 load but not HPV-16 integration load measured by real-time PCR was associated with AIN-2,3.

Management of anal squamous intraepithelial lesions

Anal squamous intraepithelial lesions include both low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL) and are caused by chronic infection with the human papillomavirus (HPV). The disease is increasing in both incidence and prevalence, especially among patients with the following risk factors: homosexual men, acquired or iatrogenic immunosuppression, and presence of other HPV-related diseases. Although the natural history of the disease is unknown, there is significant evidence that untreated HSIL progresses to squamous cell carcinoma in 11% of patients and in up to 50% of patients with extensive disease and immunosuppression. Anal cytology and reflex HPV DNA testing are used to screen for disease, particularly among patients with the aforementioned risk factors. Evaluation of the patient should include physical examination and high-resolution anoscopy (HRA) to evaluate for disease above and below the dentate line. Intervention is warranted and this can be achieved in many ways. The treatment option associated with the best outcomes is ablation directed with HRA, which can be performed in the office or in the operating room with minimal morbidity. This strategy is effective in patients with both low-volume and high-volume disease and is associated with a malignant progression rate of 0.4% in patients with treated HSIL.

Management of anal squamous intraepithelial lesions

Anal squamous intraepithelial lesions include both low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL) and are caused by chronic infection with the human papillomavirus (HPV). The disease is increasing in both incidence and prevalence, especially among patients with the following risk factors: homosexual men, acquired or iatrogenic immunosuppression, and presence of other HPV-related diseases. Although the natural history of the disease is unknown, there is significant evidence that untreated HSIL progresses to squamous cell carcinoma in 11% of patients and in up to 50% of patients with extensive disease and immunosuppression. Anal cytology and reflex HPV DNA testing are used to screen for disease, particularly among patients with the aforementioned risk factors. Evaluation of the patient should include physical examination and high-resolution anoscopy (HRA) to evaluate for disease above and below the dentate line. Intervention is warranted and this can be achieved in many ways. The treatment option associated with the best outcomes is ablation directed with HRA, which can be performed in the office or in the operating room with minimal morbidity. This strategy is effective in patients with both low-volume and high-volume disease and is associated with a malignant progression rate of 0.4% in patients with treated HSIL.

Human papillomavirus genotypes in anal intraepithelial neoplasia and anal carcinoma as detected in tissue biopsies

Human papillomavirus (HPV) infection strongly correlates with the development of anal intraepithelial neoplasias and carcinomas; however, few studies have characterized the distribution of the specific subtypes of the virus in the varying grades of dysplasia. This report characterizes the distribution of HPV 16/18 in surgical specimens with anal intraepithelial neoplasia (AIN) I-III and histological variants of anal carcinoma. A total of 111 anal surgical specimens with no dysplasia (10), AIN I-III (53), and anal carcinomas (48) were evaluated for the presence of high-risk HPV infection and subtyped by nested PCR or the Invader Assay. High-risk virus types were detected in progressively greater number of anal intraepithelial lesions from 56% in low grade to 88% in high grade. Type 16 was the prevalent subtype and was noted in 28% of low grade and 68% of high-grade lesions. Moderate dysplasias showed type 16 in 20%, a prevalence similar to that in low-grade lesions. The non-16/18 subtypes of the virus predominated and were present in 50% of the cases. Most (89%) squamous carcinomas were associated with high-risk viruses, 68% with type 16, a prevalence similar to that noted in high-grade dysplasia. Non-16/18 subtypes were encountered more frequently in squamous carcinomas from immunodeficient individuals (57% cases) as compared with immunocompetent individuals (18% cases). The similarity in the prevalence of type 16 in high-grade dysplasia and squamous carcinomas suggests that anal intraepithelial lesion III is the true precursor of squamous carcinoma and warrants aggressive management. Anal intraepithelial lesions II showed a virus distribution that was similar to low-grade dysplasia. In addition, a subset of these that were associated with type 16 or 18 showed progression, whereas those associated with non-16/18 subtypes regressed, thereby raising the possibility of conservative management for these lesions.

Anal cancer treated with radio-chemotherapy: correlation between length of treatment interruption and outcome

AIM

The purpose of this study was the evaluation of the feasibility and outcome of definitive radio-chemotherapy without split-course technique but with individualised short treatment interruption in anal cancer patients.

METHOD

Between 1993 and 2008, 101 patients with anal cancer were treated in our institution with definitive radio-chemotherapy with individualised short treatment interruptions. Treatment was halted independent of dose in case of acute grade 3 toxicities and started again until improvement. Short interruption was defined as completing treatment without exceeding six cumulative treatment days beyond a scheduled plan; otherwise, it was defined as prolonged interruption.

RESULTS

Median overall treatment time was 47 days corresponding to an interruption of six cumulative treatment days. Fifty-one patients (50%) had treatment interruption of <or=6 days. No acute grade 4 toxicities were observed. One fatality occurred during treatment due to ileus-like symptoms according to acute grade 5 toxicity. After a median follow-up of 56 months, the 5-year actuarial rates for local control comparing patients with short vs. prolonged treatment interruption were 78% vs. 81% (p = 0.904) and, for colostomy-free survival, 83% vs. 85% (p = 0.784), respectively.

CONCLUSIONS

Definitive radio-chemotherapy with short individualised treatment interruption shows high local control and colostomy-free survival rates.

HPV infection in an HIV-positive patient with primary squamous cell carcinoma of rectum

Primary squamous cell carcinoma (SCC) of the colorectum is a rare malignancy of unknown etiology and pathogenesis. We report a case of primary SCC of the rectum. A 55-year-old man with a rectal tumor and human immunodeficiency virus (HIV) infection was referred to our hospital. Histopathology of biopsy specimens showed characteristics of SCC. We diagnosed the patient as having primary moderately differentiated SCC of the rectum according to the criteria proposed by Cooper. Human papillomavirus (HPV) DNA was amplified by polymerase chain reaction analysis of unfixed tumor biopsy specimens. In addition, no p53 overexpression or nuclear staining of retinoblastoma protein (Rb) was observed in neoplastic cells by immunohistochemical staining. We suggest from our case that HPV infection following the inactivation of the cellular tumor suppressor Rb and the immune suppression induced by HIV infection play an etiologic role in the pathogenesis of rectal SCC, consistent with the well-established concept of HPV-associated anal carcinogenesis.

[Experimental vaccines for sexually transmitted infections]

INTRODUCTION

Sexually transmitted infections (STIs) are major global public health problems. Present strategies for prevention have limitations. Vaccines are an attractive addition to the current prevention armamentarium because they provide durable protection and do not require repetitive adherence to be effective. Challenges for vaccination include induction and long-term maintenance of mucosal immune responses in the female genital tract.

VACCINES

A REALISTIC GOAL? For the time being, US Centers for Disease Control and Prevention have recommended only hepatitis and HPV immunization to be routinely offered. Final, III stage trials are underway on other prophylactic vaccines for human papillomavirus and genital herpes. Though vaccines against Chlamydia trachomatis and Neisseria gonorrhoeae are in early stages of development they do offer the hope of preventing pelvic inflammations. The high incidence of HIV-infection for which a vaccine would not be readily available, "cries out" for an effective vaccine.

VACCINES FOR HPV INFECTIONS

According to a recent meta-analysis of worldwide prevalence data, vaccinating with HPV-16/18 VLP against HPV-16 and HPV-18 could prevent over 70% of invasive cervical cancer worldwide. The latest release of data from the phase III trial of a quadrivalent recombinant non-infectious vaccine HPV-6/11/16/18 L1 VLP, including HPV types 6, 11, 16, 18 have given complete protection against HPV-16/18-related cervical intraepithelial neoplasias 1, 2/3, and adenocarcinoma in situ and cancer through 2 years of post-vaccination follow up.

CONCLUSION

Despite the fact that the development of vaccines for STI prevention was rather slow in the past, the ideal vaccine would decrease transmission of the infection between partners and would prevent complications of disease. Moreover, in future decades, increasingly successful universal vaccination of newborns and children will substantially reduce the need for vaccination of persons with specific risk factors, including sexual risk.

Human papillomavirus type distribution in anal cancer and anal intraepithelial lesions

A systematic review was conducted of HPV type distribution in anal cancer and anal high-grade and low-grade squamous intraepithelial lesions (HSIL and LSIL). A Medline search of studies using PCR or hybrid capture for HPV DNA detection was completed. A total of 1,824 cases were included: 992 invasive anal cancers, 472 HSIL cases and 360 LSIL cases. Crude HPV prevalence in anal cancer, HSIL, and LSIL was 71, 91 and 88%, respectively. HPV16/18 prevalence was 72% in invasive anal cancer, 69% in HSIL and 27% in LSIL. The HPV 16 and/or 18 prevalence in invasive anal cancer cases was similar to that reported in invasive cervical cancer. If ongoing clinical trials show efficacy in preventing anal HPV infection and associated anal lesions, prophylactic HPV vaccines may play an important role for the primary prevention of these cancers in both genders.

Prevalence and type distribution of human papillomavirus in carcinoma and intraepithelial neoplasia of the vulva, vagina and anus: a meta-analysis

This meta-analysis investigated human papillomavirus (HPV) prevalence in vulvar, vaginal and anal intraepithelial neoplasia (VIN, VAIN, AIN) grades 1-3 and carcinoma from 93 studies conducted in 4 continents and using PCR assays. Overall HPV prevalence was 67.8%, 85.3% and 40.4% among 90 VIN1, 1,061 VIN2/3 and 1,873 vulvar carcinomas; 100%, 90.1% and 69.9% among 107 VAIN1, 191 VAIN2/3 and 136 vaginal carcinomas; and 91.5%, 93.9% and 84.3% among 671 AIN1, 609 AIN2/3 and 955 anal carcinomas, respectively. HPV16 was found more frequently (>75%) and HPV18 less frequently (<10%) in HPV-positive vulvar, vaginal and anal carcinomas than in cervical carcinoma. HPV6 and 11 were common in VIN1 and AIN1, but not in VAIN1. HPV prevalence in vulvar carcinoma varied most by histological type (69.4% in warty-basaloid and 13.2% in keratinized type) and was also higher in women 60 years or younger and in studies carried out in North America. HPV prevalence in anal carcinoma was higher among women (90.8%) than men (74.9%), but no difference by gender emerged in North America. The majority of AIN2/3 derived from studies of HIV-positive individuals and/or men who have sex with men. Among AIN2/3, HIV infection was associated with higher HPV prevalence, more multiple-type infections and a relative under-representation of HPV16. In conclusion, approximately 40% of vulvar, 60% of vaginal and 80% of anal carcinoma may be avoided by prophylactic vaccines against HPV16/18. This proportion would be similar for the corresponding high-grade lesions of the vagina and anus, but higher for VIN2/3 (75%) than for vulvar carcinoma.

Genotyping of human papillomavirus DNA in anal biopsies and anal swabs collected from HIV-seropositive men with anal dysplasia

BACKGROUND

Human papillomavirus (HPV) causes anal intraepithelial neoplasia (AIN) in HIV-seropositive men. The detection of HPV genotypes in anal biopsies and swabs was compared.

METHODS

HPV DNA was detected in anal swabs and biopsies obtained concurrently from 154 HIV-seropositive men [31 without AIN, 60 low-grade AIN (AIN-1), 62 high-grade AIN (AIN-2,3), and 1 indeterminate AIN] under or eligible to highly active antiretroviral therapy.

RESULTS

HPV DNA was detected in 24.2% of normal biopsies compared with 93.5% with AIN-2,3 (P < 0.001) and 88.3% with AIN-1 (P < 0.001). The proportion of biopsies containing multiple genotypes was greater in AIN-1 (n = 21, 35.0%; P = 0.002) and AIN-2,3 (n = 38, 58%; P < 0.001) than in normal biopsies (n = 2, 6.5%). The most frequent genotypes in order of frequency were in AIN-2,3 biopsies HPV-16, 18, 58, and 45 and were in AIN-1 biopsies HPV-6, 11, 16, and 39. Controlling for age, CD4 count, and smoking, the presence of high-risk HPV DNA in biopsies [odds ratio (OR) = 50.8, 95% confidence interval (CI): 13.0 to 199.5] but not in swabs (OR = 2.0, 95% CI: 0.6 to 7.0) was associated with AIN-2,3.

CONCLUSIONS

AIN-2,3 was associated with high-risk HPV infection detected in biopsies but not in swabs in men under or starting highly active antiretroviral therapy, possibly due to the presence of HPV foci outside of the neoplastic lesion.

Diagnostic problems in anal pathology

Anal squamous cell carcinoma and its precursor lesions are increasing in incidence in the United States and Europe. This trend predates human immunodeficiency virus/acquired immune deficiency syndrome and has been associated with persistent high-risk human papilloma virus (HPV) genotype infection, previous lower genital tract dysplasia/carcinoma, high frequency anoreceptive intercourse, heavy cigarette smoking, immunosuppression in solid organ transplant and immune disorders, and human immunodeficiency virus seropositivity. Screening protocols for at-risk patients are under active investigation and pathologists are often asked to assess anal canal and perianal biopsies for the presence of dysplasia and/or invasive carcinoma. Because underdiagnosis and overdiagnosis of anal cancer and precancer may lead to inappropriate treatment, it is important for the pathologist to be aware of current screening strategies, specific risk lesions, and the role of pathology in initial diagnosis and evaluation of anal biopsy and/or resection specimens. Standardized histologic criteria and uniform terminology should be used for reporting all anal canal and perianal squamous intraepithelial lesions. HPV subtyping, anal cytology, and recently identified biomarkers, such as p16 and Becton Dickinson ProEx C may provide additional information in problematic cases, but it is important to be aware of the limitations of these assays. HPV has been linked to all the major histologic subtypes of anal carcinoma (eg, basaloid, cloacogenic, transitional, etc.) and this association is strongest for anal canal lesions. With the possible exception of the microcystic pattern, histologic subtype does not seem to predict prognosis; and anal squamous cell carcinomas should be classified as either keratinizing or nonkeratinizing. Poorly differentiated squamous cell carcinomas have a worse prognosis and should be distinguished from poorly differentiated adenocarcinoma, melanoma, and neuroendocrine tumors. Very well differentiated squamous cell carcinoma with pushing margins (so-called giant condyloma of Buschke and Lowenstein) should be classified as verrucous carcinoma; this tumor shows aggressive local infiltration but does not metastasize. As all anal condylomata may harbor foci of high-grade dysplasia or invasive carcinoma, careful sectioning and complete histologic examination is required.

Epidemiology of human papillomavirus infection in men, cancers other than cervical and benign conditions

Human papillomavirus (HPV) infection is commonly found in the genital tract of men and women with or without any clinical lesion. The association of HPV DNA with several different ano-genital cancers other than cervical has been reported for the vulva, vagina, anus and penis. HPV DNA has also been identified in head and neck cancers in the oral cavity, the oropharynx and the larynx in both sexes. In men, 80-85% of anal cancers and close to 50% of penile cancers are associated with HPV infection. In women, HPV DNA is prevalent in 36-40% vulvar cancer cases and close to 90% of vaginal cancers. There is limited data available on the natural history and HPV-related diseases in the genital tract in men, although studies are ongoing. Efficacy of HPV vaccines in the prevention of HPV infection and disease among men also remains unknown. Among HPV DNA positive ano-genital cancer cases, HPV-16 is the most frequently found followed distantly by HPV-18. In benign HPV-related diseases such as genital warts or recurrent respiratory papillomatosis HPV-6 and 11, the two most frequent non-oncogenic types, are the predominant types detected. Oncogenic types are rarely detected. In this article we summarize and review studies describing the natural history of HPV infections among men and its impact on HPV related disease in women. We summarize the evidence linking HPV in the epidemiology and etiology of cancers of the vulva, vagina, anus and oropharynx and present recent estimates of the burden of and HPV type distribution in genital warts and in cases of HPV infection of the airways.

HPV DNA detection and genotyping in 21 cases of primary invasive squamous cell carcinoma of the vagina

Primary invasive squamous cell carcinoma of the vagina is rare, and the role of human papilloma virus in its pathogenesis remains unclear. The aims of our study were to determine the distribution of human papilloma virus genotypes in 21 cases of primary invasive squamous cell carcinoma of the vagina and to correlate human papilloma virus genotype with histological subtypes. Patients' clinical records were reviewed for demographic data and the stage of the disease. Tumors (n=21) were classified according to the World Health Organization criteria. Human papilloma virus genotyping (INNO-LiPA HPV Genotyping) was performed in the whole series, and statistical analysis was performed with Fisher's Exact Test and with Student's t-test. The patients' age ranged from 36 to 88 (mean 65) years. Six cases were keratinizing squamous cell carcinoma, and 15 cases were non-keratinizing squamous cell carcinoma (seven non-keratinizing not otherwise specified, three basaloid, and five warty types). The median age of patients with keratinizing squamous cell carcinoma was 73.8 years and that of non-keratinizing squamous cell carcinoma patients was 61.5 years (P=0.08). Human papilloma virus DNA was detected in 17 cases (81%): 13 non-keratinizing squamous cell carcinoma (87%) and four keratinizing squamous cell carcinoma (67%) (P=0.31). The human papilloma virus genotypes identified were: 6, 11, 16, 18, 31, 33, 35, 40, and 58, with human papilloma virus 16 DNA the most prevalent (33%). Invasive squamous cell carcinoma of the vagina is frequently associated with human papilloma virus infection, and human papilloma virus 16 is the most common genotype. Although without statistical significance, keratinizing squamous cell carcinoma is more frequent in older patients, whereas non-keratinizing squamous cell carcinoma more frequently affects younger women. All studied histological subtypes are strongly associated with human papilloma virus infection.

High-risk human papillomavirus infections in breast cancer in Syrian women and their association with Id-1 expression: a tissue microarray study

High-risk human papillomaviruses (HPVs) could be important risk factors for breast carcinogenesis and metastasis. Based on this hypothesis, we recently studied the effect of E6/E7 onco-proteins of high-risk HPV type 16 in two non-invasive human breast cancer cell lines, BT20 and MCF7; we reported that E6/E7 converts these cell lines to invasive cells. This is accompanied by an overexpression of Id-1, which is an important regulator of breast metastasis. In this investigation, we examined the presence of high-risk HPVs (16, 18, 31, 33 and 35) and the expression of their E6 onco-protein as well as their correlation with Id-1 gene expression, using polymerase chain reaction (PCR) and tissue microarray (TMA) analysis, respectively, in a cohort of 113 Syrian breast cancer patients. We found that high-risk HPV types 16, 18, 31, 33 and 35 are present in 8.84, 9.73, 7.07, 55.75 and 37.16% of our samples, respectively, which represent invasive breast cancers. Overall, 69 (61.06%) of the 113 samples are HPV positive; among these specimens 24 tissues (34.78%) are coinfected with more than one HPV type. Furthermore, we report that the expression of the E6 onco-protein of these high-risk HPVs is correlated with Id-1 overexpression in the majority of invasive breast cancer tissue samples. Our data suggest that high-risk HPV infections are associated with human breast cancer progression in Syrian women.

The future of vaccines for cervical cancer

Cervical cancer continues to cause significant morbidity and mortality worldwide, making prophylactic cervical cancer vaccines an important focus for cervical cancer prevention. The increasing accessibility of these vaccines worldwide has the potential to greatly decrease the incidence and burden of disease in the future. However, current prophylactic vaccines offer no therapeutic benefit for persons already infected with human papillomavirus HPV types targeted by vaccines or persons with precancerous lesions or cervical cancer. The protection offered by current vaccines is primarily against HPV types used to derive the vaccine, although partial cross-protection for related virus types has been observed. Herein, we describe findings from preclinical and clinical studies that employ vaccine strategies that have the potential to shape the future of vaccines against cervical cancer. Modalities include prophylactic strategies to target more oncogenic virus types by using the minor capsid antigen L2 and/or by increasing the number of types used to derive virus-like particle vaccines. Therapeutic strategies include the development of vaccines against HPV early proteins (targets for cellular immunity) for the resolution of precancerous lesions and cervical cancer. Future applications of existing virus-like particle-based vaccines are also discussed.

Involvement of human papillomavirus infections in prostate cancer progression

High-risk human papillomaviruses (HPVs) are sexually transmitted and have been associated with several human carcinomas especially cervical and colorectal. On the other hand, a small number of studies have examined the presence of high-risk HPV in human prostate cancer tissues. Currently, the presence and role of high-risk HPV infections in prostate carcinogenesis remain unclear because of the limited number of investigations. This raises the question whether high-risk HPV infections play any role in human prostate cancer development. However, other investigators and our group were able to immortalize normal and cancer prostate epithelial cells in vitro by E6/E7 of HPV type 16. In this paper, we propose the hypothesis that normal and cancer prostate epithelial cells are susceptible to persistent HPV infections; therefore, high-risk HPV infections play an important role in the progression of prostate cancer. We believe that an international collaboration of epidemiological studies and more molecular biology investigations are necessary to answer these important questions.

Prevalence and factors associated with anal lesions mediated by human papillomavirus in men with HIV/AIDS

Summary

Prevalence and risk factors for human papillomavirus-related anal lesions were evaluated in 60 men with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Patients underwent anal cytology, anuscopy under colposcopic vision and anal biopsy for detection of the lesions. The mean age was 41.9 years and the mean time of HIV infection was 6.8 years, 88.3% of them having been on highly active antiretroviral therapy for an average of 6.5 years. Homosexuals represented 43.3% and bisexuals 15.0% whereas heterosexuals comprised 41.7%. The prevalence of anal lesions detected by anuscopy under colposcopic vision, cytology and biopsy were, respectively, 35.0, 16.7 and 23.3%. Homosexuals or bisexuals accounted for 85.7% of the patients with an abnormal biopsy, the remaining 14.3% being heterosexuals (P = 0.02). The T-CD4+ lymphocyte count, HIV viral load and use of antiretrovirals did not reveal any association with anal lesions. The occurrence of anal lesions was high in the individuals with HIV/AIDS, especially in the homosexuals and bisexuals, but it also occurred in heterosexuals, justifying the screening of anal lesions of all men with the infection.

A Phase 1 Clinical Study of Intravenous Administration of PV701, an Oncolytic Virus, Using Two-Step Desensitization

PURPOSE

In a previous phase 1 study, adverse events, especially flu-like symptoms, were observed mainly following the first i.v. bolus dose of PV701, an oncolytic Newcastle disease virus. Desensitization to adverse events of subsequent doses occurred, allowing a 10-fold increase in the maximum tolerated dose for these doses. Although one-step desensitization (a single desensitizing dose with higher subsequent doses) addressed the tolerability of high repeat doses, additional testing was required to further improve tolerability of the initial dose. This study tested the hypothesis that two-step desensitization, using two dose increments before high repeat doses, would be well tolerated.

EXPERIMENTAL DESIGN

Sixteen adults with incurable solid tumors were enrolled. Cycles consisted of six PV701 doses over 2 weeks followed by a 1-week rest. Doses 1 to 2 were 1 and 12 x 10(9) plaque-forming units (pfu)/m(2), respectively, whereas doses 3 to 6 were escalated by cohort from 24 to 120 x 10(9) pfu/m(2).

RESULTS

No dose-limiting toxicities were observed, permitting dose escalation through cohort 4 (1, 12, 120, 120, 120, 120 x 10(9) pfu/m(2)). Mild flu-like symptoms were common following the first infusion, diminished with repeated dosing, and were less pronounced than those seen previously. Tumor regression was observed in a patient with anal carcinoma who enrolled with stable disease following palliative radiotherapy. Four patients with clearly progressing cancer before enrollment had disease stabilization of >/=6 months.

CONCLUSIONS

This novel two-step desensitization improved patient tolerability compared with the previous regimen. Toxicities were predictable and manageable. PV701, the first oncolytic virus to enter phase 1 i.v. testing, continues to show single-agent activity, warranting planned phase 2 trials.