Tracing human papillomavirus DNA in nasal polyps by polymerase chain reaction

Human papilloma virus in the etiopathogenesis of allergic nasal polyposis: A prospective study

PURPOSE

To evaluate and compare the prevalence of high-risk HPV and low-risk HPV types in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) and healthy controls.

MATERIALS AND METHODS

A prospective cohort study was conducted in a tertiary care hospital on the patients of CRSwNP undergoing surgical management. All patients underwent preoperative endoscopic evaluation and radiological assessment using NCCT of the nose and paranasal sinuses. The severity of the disease was graded using the Lund-Mackay score on NCCT. All patients underwent endoscopic polypectomy and the sample of tissues was sent for HPV DNA detection using Hybrid Capture II® technique. The clinicopathological characteristics of HPV positive and negative patients were compared.

RESULTS

Sixty cases and 20 controls were included in the study. All controls were negative for HPV DNA. 27 patients (45%) had the presence of HPV DNA, out of which 23 had only LR-HPV and 1 had only HR-HPV types. Three patients had both HR-HPV and LR-HPV subtypes. There was a significant difference between the cases and controls for the presence of HPV DNA (p < 0.001). However, the patients with HPV-positive DNA in the nasal specimen did not differ significantly from HPV-negative patients in age, gender, or severity of the disease.

CONCLUSIONS

Human papillomaviruses may play a significant role in the etiopathogenesis of CRSwNP, however, do not impact the degree of sinus involvement.

Association between oncogenic human papillomavirus type 16 and Killian polyp

BACKGROUND

Killian polyp (KP) is a benign lesion that arises from the maxillary sinus. The etiology of KP is unknown. The aim of this study was to investigate the potential involvement of human papilloma- (HPV) and polyoma-viruses (HPyV) infections in the onset of KP.

METHODS

DNA from antral (n = 14) and nasal (n = 14) KP fractions were analyzed for HPV and HPyV sequences, genotypes, viral DNA load and physical status along with expression of viral proteins and p16 cellular protein.

RESULTS

The oncogenic HPV16 was detected in 3/14 (21.4%) antral KPs, whilst nasal KPs tested HPV-negative (0/14). The mean HPV16 DNA load was 4.65 ± 2.64 copy/104 cell. The whole HPV16 episomal genome was detected in one KP sample, whereas HPV16 DNA integration in two KPs. P16 mRNA level was lower in the KP sample carrying HPV16 episome than in KPs carrying integrated HPV16 and HPV- negative KPs (p< 0.001). None of the antral and nasal KP samples tested positive for HPyV DNA (0/28).

CONCLUSIONS

A fraction of KP tested positive for the oncogenic HPV16. HPV16 detection in the KP antral portion may be consistent with HPV16 infection derived from the maxillary sinus. HPV16 DNA integration represents a novel finding. Altogether, these data improve our knowledge on the association between KP and HPV infection, whereas it indicates that the KP onset is heterogeneous.

Human papillomavirus and infiltration of CD8- and Foxp3-positive immune cells in sinonasal inverted papillomas

Background: Sinonasal inverted papilloma (IP) is a benign tumor with a high risk of local recurrence and a potential to malignify and Human papillomavirus (HPV) has been suggested an etiological factor. p16INK4a (p16) overexpression is considered a surrogate marker for HPV, but whether p16 and HPV correlate to IP is uncertain. Besides, a prognostic role of tumor infiltrating lymphocytes (TILs) are observed in many tumors, however their role in IP is sparsely studied. Aims/objectives: We hence analyzed IPs for the presence and the prognostic role of HPV and p16 overexpression together with CD8+ and FoxP3+ TILs in a population-based study. Material and methods: 98 IP patients diagnosed 2001-2010 were identified from the Swedish Cancer Registry and analyzed for HPV by PCR and p16, CD8 and FoxP3 was by immunohistochemistry. Results: In total, 12.2% of the IPs were HPV-positive (nine HPV-11, two HPV-6 and one HPV-45). Patients with HPV-positive lesions were younger (p = .003) and tended to present with more dysplasia. No correlation was observed between TILs and prognosis. Conclusions and significance: Our data suggests that patients with HPV-positive IPs present with different clinical characteristics, suggesting possibly different disease entities. Moreover, recurrences may occur >5 years, which should be considered in the follow-up.

HPV and Oropharyngeal Cancer in the Eighth Edition of the TNM Classification: Pitfalls in Practice

This review is a call for mindfulness and precision when applying TNM 8 in oropharyngeal cancers. Implications, intentions, and weaknesses of TNM 8 are addressed in light of our own investigations and the published literature. In TNM 8, the impact of p16^INK4A status on the staging of oropharyngeal SCC highlights i) that underlying evidence is scarce, ii) its stage grouping exclusively has prognostic intention, and iii) that a noncritical application of TNM 8 might negatively impact the patients' survival as the perception of TNM 8 as having therapeutic intention may lead to de-escalating treatment regimens in p16^INK4A-positive cases, specifically when grouped into stage I despite the presence of neck metastasis. If other parameters from HPV positivity that also have a negative impact on the patient's survival, such as smoking or the presence of comorbidity, are neglected in therapy planning, survival outcomes might even become worse. Future studies applying TNM 8 and further investigating the value of p16^INK4A as surrogate marker for active HPV infections will identify whether or not changes in TNM 8 should have therapeutic implications in HPV-associated, only p16^INK4A-positive cases or whether this impact additionally holds true for nontonsillar cancers.

Investigation of Human Papillomavirus (HPV) and Epstein-Barr Virus (EBV) in antrochoanal polyps

OBJECTIVES/HYPOTHESES

This study aimed to investigate the presence of HPV (HPV types 11 and 16) and EBV in antrochoanal polyps and to contribute to the current literature in this regard.

STUDY DESIGN

A case-control study.

METHODS

A total of 100 patients (including 43 patients undergoing surgery for antrochoanal polyp, 27 patients undergoing surgery for nasal polyp, and 30 patients undergoing surgery for hypertrophic inferior turbinate) were included in this study. DNA was isolated from formalin-fixed, paraffin-embedded samples with the aid of the Bioneer's AccuPrep Genomic DNA Extraction Kit. In the obtained genomic DNAs, while the detection of HPV DNA was performed using the nested-PCR method, the detection of HPV types 11/16 and EBV DNA was performed using the RT-PCR method.

RESULTS

The mean age of the patients with antrochoanal polyp was 26.7 ± 15.4 years (range 7-70). There were 20 (46.5%) women and 23 (53.5%) men in the antrochoanal polyp group. HPV DNA was positively detected using the nested-PCR method in 14 (32.6%) of the patients with antrochoanal polyp and in 3 (11.1%) of the patients with nasal polyp. HPV DNA was not detected in the hypertrophic inferior turbinate group (control group). There was a statistically significant difference between all groups in terms of HPV DNA positivity. In the antrochoanal polyp group, 2 patients had HPV 11 positivity and 12 patients had HPV 16 positivity. In the nasal polyp group, 1 patient had HPV 11 positivity and 2 patients had HPV 16 positivity. EBV DNA was positively detected in 16 (37.2%) of the patients with antrochoanal polyp, in 11 (40.7%) of the patients with nasal polyp and in 8 (26.7%) of the patients with hypertrophic inferior turbinate, respectively. There was no statistically significant difference between the groups in terms of EBV DNA positivity.

CONCLUSIONS

This study demonstrates that there is a need for further studies investigating the presence of viruses in antrochoanal polyps.

The role of human papilloma virus and herpes viruses in the etiology of nasal polyposis

BACKGROUND/AIM

The aim of this study was to investigate the etiological role of human papilloma virus (HPV), herpes simplex virus (HSV), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpes virus-6 (HHV-6) and -7 (HHV-7) in the occurrence of nasal polyposis.

MATERIALS AND METHODS

Nasal polyp samples from 30 patients with nasal polyposis and normal nasal mucosa from 10 patients without nasal polyps were obtained. DNA was extracted from tissues. Real-time polymerase chain reaction was performed for all runs.

RESULTS

No HSV-1, HSV-2, or VZV was detected in the samples. Among the patient samples, EBV and HHV-7 DNA were detected in 18 (60%), HHV-6 was detected in 20 (66.7%), and HPV was detected in 4 (13.3%) samples. Among the controls, CMV DNA was positive in one (10%). EBV was positive in 5 (50%), HHV-6 and HHV-7 were positive in 7 (70%), and HPV was positive in 2 (20%) samples. No significant difference was found among the groups with any test in terms of positivity.

CONCLUSION

The association of Herpesviridae and HPV with the pathogenesis of nasal polyps was investigated in this study and no relationship was found. Thus, these viruses do not play a significant role in the formation of nasal polyps.

Human Papillomavirus (HPV) Prevalence in Nasal and Antrochoanal Polyps and Association with Clinical Data

Objectives

The pathogenesis of sinonasal polyposis remains unclear, in spite of several investigative approaches. Antrochoanal polyps, a subgroup of sinonasal polyposis along with allergic- and chronic-inflammatory nasal polyps, mostly originate from the maxillary sinus and develop as a unilateral, pedunculated mass towards the nasopharynx. The human papillomavirus (HPV) is discussed as a possible causative and influencing factor in development and progression of sinonasal polyposis. This study aims to elucidate HPV frequency in nasal polyps and antrochoanal polyps.

Materials and Methods

Genomic DNA from 257 tissue specimens (166 nasal polyps, 39 antrochoanal polyps and 52 nasal turbinates) was subjected to three different established HPV- polymerase chain reaction assays, testing for 37 low- and high-risk HPV. In addition, immunohistochemical analyses for HPV16 were carried out, as well as immunohistochemistry and western blots of p16, a biomarker for HPV induced cancer.

Results

HPV-DNA was detected in 53.8% of antrochoanal polyps, 15.1% of nasal polyps, and 5.8% of nasal turbinates. HPV16 was the predominant type with a detection rate of 76% in nasal polyps and 62% in antrochoanal polyps. Immunohistochemically, HPV positive tissues stained positive for HPV16 antigens and p16 in epithelial cell layers. No significant p16 overexpression was traceable in antrochoanal polyps, nasal polyps and nasal turbinates by western blot. There was no correlation of HPV-status with sex, age, smoking, alcohol consumption or allergic background.

Conclusion

The present study shows a significant frequency of high-risk type HPV16 in antrochoanal polyps. Absence of oncogenic transformation or correlation of the HPV-status with clinical data suggests a latent superinfection, possibly because of anatomical proximity to the oropharynx.

Herpes viruses and human papilloma virus in nasal polyposis and controls

Introduction

Chronic rhinosinusitis with nasal polyps is a multifactorial disease entity with an unclear pathogenesis. Contradictory data exist in the literature on the potential implication of viral elements in adult patients with chronic rhinosinusitis.

Objective

To compare the prevalence of human herpes viruses (1–6) and Human Papilloma Virus in adult patients with chronic rhinosinusitis with nasal polyps and healthy controls.

Methods

Viral DNA presence was evaluated by real-time polymerase chain reaction application to nasal polyps specimens from 91 chronic rhinosinusitis with nasal polyps patients and nasal turbinate mucosa from 38 healthy controls.

Results

Epstein–Barr virus positivity was higher in nasal polyps (24/91; 26.4%) versus controls (4/38; 10.5%), but the difference did not reach significance (p = 0.06). Human herpes virus-6 positivity was lower in nasal polyps (13/91; 14.29%) versus controls (10/38; 26.32%, p = 0.13). In chronic rhinosinusitis with nasal polyps group, 1 sample was herpes simplex virus-1-positive (1/91; 1.1%), and another was cytomegalovirus-positive (1/91; 1.1%), versus none in controls. No sample was positive for herpes simplex virus-2, varicella-zoster virus, high-risk-human papilloma viruses (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59) and low-risk-human papilloma viruses (6, 11).

Conclusion

Differences in Epstein–Barr virus and human herpes virus-6 positivity among patients with chronic rhinosinusitis with nasal polyps and healthy controls are not statistically significant, weakening the likelihood of their implication in chronic rhinosinusitis with nasal polyps pathogenesis.

Infection and HLA-G molecules in nasal polyposis

Sinonasal polyposis (SNP) is a chronic inflammatory pathology with an unclear aetiopathogenesis. Human papillomavirus (HPV) infection is one candidate for the development of SNP for its epithelial cell trophism, hyperproliferative effect, and the induction of immune-modulatory molecules as HLA-G. We enrolled 10 patients with SNP without concomitant allergic diseases (SNP-WoAD), 10 patients with SNP and suffering from allergic diseases (SNP-WAD), and 10 control subjects who underwent rhinoplasty. We analyzed the presence of high- and low-risk HPV DNA and the expression of membrane HLA-G (mHLA-G) and IL-10 receptor (IL-10R) and of soluble HLA-G (sHLA-G) and IL-10 by polyp epithelial cells. The results showed the presence of HPV-11 in 50% of SNP-WoAD patients (OR:5.5), all characterized by a relapsing disease. HPV-11 infection was absent in nonrelapsing SNP-WoAD patients, in SNP-WAD patients and in controls, supporting the hypothesis that HPV-11 increases risk of relapsing disease. HPV-11 positive SNP-WoAD patients presented with mHLA-G and IL-10R on epithelial cells from nasal polyps and showed secretion of sHLA-G and IL-10 in culture supernatants. No HLA-G expression was observed in HPV negative polyps. These data highlight new aspects of polyposis aetiopathogenesis and suggest HPV-11 and HLA-G/IL-10 presence as prognostic markers in the follow-up of SNP-WoAD.

Human papillomavirus in non-oropharyngeal head and neck cancers: a systematic literature review

Perhaps one of the most important developments in head and neck oncology of the past decade is the demonstration that patients with human papillomavirus (HPV)-mediated oropharyngeal cancers have significantly improved outcomes, compared to HPV-negative counterpart patients. This has become the basis for clinical trials investigating the impact on "treatment deintensification" for patients with HPV-mediated oropharyngeal cancers. Unfortunately, the significance of HPV in non-oropharyngeal head and neck cancers is much less certain. Our goal is to systematically review the published data regarding the role HPV in carcinomas of the oral cavity, larynx, sinonasal tract and nasopharynx with respect to HPV detection frequency, viral activity, and association with outcome. We also present preliminary data on HPV16/18 transcriptional status in oral cavity carcinomas, as well as salivary gland neoplasia, as determined by nested reverse transcription PCR for HPV E6/E7 RNA. The weighted prevalence (WP) of HPV DNA detection in 4,195 oral cavity cancer patients is 20.2 %, (95 % CI 16.0 %, 25.2 %). HPV16 is the most common type detected. Importantly, no data currently demonstrates a significant association between the presence of HPV DNA and improved outcome. The WP of HPV DNA in 1,712 laryngeal cancer patients is 23.6 %, (95 % CI 18.7 %, 29.3 %). Similarly, no association has yet been demonstrated between HPV DNA status and outcome. The WP of HPV DNA detection in 120 sinonasal cancer patients is 29.6 % (95 % CI 17.8 %, 44.9 %), and in 154 nasopharyngeal carcinoma patients is 31.1 %, (95 % CI 20.3 %, 44.5 %). Recent preliminary data also suggests an association between HPV and certain salivary gland neoplasms. The clinical significance of these findings is unclear. The published data strongly support the need for studies on patients with oral and laryngeal carcinomas that will be powered to find any differences in clinical outcome with respect to HR-HPV and p16 overexpression.

Prevalence of human papillomavirus, Epstein-Barr virus, p21, and p53 expression in sinonasal inverted papilloma, nasal polyp, and hypertrophied turbinate in Hong Kong patients

BACKGROUND

The purpose of this study of human papillomavirus (HPV), Epstein-Barr virus (EBV), p21, and p53 in sinonasal inverted papilloma (IP) was to help elucidate its pathogenesis.

METHODS

Seventy-three IPs, 48 nasal polyps, and 85 hypertrophied turbinates were subjected to HPV polymerase chain reaction (PCR) study. Seventy-three IPs, 30 nasal polyps, and 32 hypertrophied turbinates were subjected to EBV in situ hybridization (ISH), p21, and p53 immunohistochemical (IHC) studies.

RESULTS

HPV was positive in 3 of 73 IPs (4.1%). All specimens were EBV negative. In all, 99% of IPs showed strong and diffuse p21 nuclear reactivity. Most nasal polyps and hypertrophied turbinates showed weak to moderate immunoreactivity of the basal and parabasal cells. Only focal p53 immunoreactivity of the basal and parabasal cells was found in 19% of IPs and 40% of nasal polyps.

CONCLUSIONS

HPV prevalence of our IP is low. EBV is not present in IP. High p21 and low p53 expression in IP suggests a non-p53-dependent regulation pathway.

Human papillomavirus infection in nasal polyps in a Chinese population

In order to determine the prevalence and genotype distribution of human papillomavirus (HPV) infection in patients with nasal polyps, a total of 204 patients with nasal polyps and 36 healthy controls were recruited for this study. Genomic DNA was extracted from paraffin-embedded tissue sections. HPV DNA genotyping was achieved by a flow-through hybridization and gene-chip method. HPV-positive infection was identified in 82 of 204 (40.2 %) patients, while HPV DNA was not found in healthy controls (P<0.05). Genotyping analysis showed that low-risk HPV genotype 11 was the most prevalent type of HPV in nasal polyps (45.28 %). Both single and multiple HPV genotype infections were found in these HPV-positive cases, although most (74.39 %) were infected with a single genotype. In addition, there was no correlation between HPV infection or HPV subtypes and the clinicopathological characteristics of patients, such as age, gender, number of surgery and disease course. The data from our study clearly demonstrated that HPV infection was associated with nasal polyps. Both high-risk HPV and low-risk HPV (LR-HPV) genotypes were identified in nasal polyp tissues, and LR-HPV-11 was the most prevalent type. Future research will explore the association of HPV infection with the development and progression of nasal polyps.

Human nasal polyp microenvironments maintained in a viable and functional state as xenografts in NOD-scid IL2rgamma(null) mice

OBJECTIVES

The objective was to develop a model with which to study the cellular and molecular events associated with nasal polyp progression. To accomplish this, we undertook to develop a system in which nondisrupted human nasal polyp tissue could be successfully implanted into severely immunocompromised mice, in which the histopathology of the original nasal polyp tissue, including inflammatory lymphocytes, epithelial and goblet cell hyperplasia, and subepithelial fibrosis, could be preserved for prolonged periods.

METHODS

Small, non-disrupted pieces of human nasal polyp tissues were subcutaneously implanted into NOD-scid IL2rgamma(null) mice. Xenografts at 8 to 12 weeks after implantation were examined histologically and immunohistochemically to identify human inflammatory leukocytes and to determine whether the characteristic histopathologic characteristics of the nasal polyps were maintained for a prolonged period. The xenografts, spleen, lung, liver, and kidneys were examined histologically and immunohistochemically and were evaluated for changes in volume. The sera of these mice were assayed for human cytokines and immunoglobulin.

RESULTS

Xenografts of human nasal polyp tissues were established after their subcutaneous implantation into NOD-scid IL2rgamma(null) mice. The xenografts were maintained in a viable and functional state for up to 3 months, and retained a histopathologic appearance similar to that of the original tissue, with a noticeable increase in goblet cell hyperplasia and marked mucus accumulation in the submucosal glands compared to the original nasal polyp tissue. Inflammatory lymphocytes present in the polyp microenvironment were predominantly human CD8+ T cells with an effector memory phenotype. Human CD4+ T cells, CD138+ plasma cells, and CD68+ macrophages were also observed in the xenografts. Human immunoglobulin and interferon-gamma were detected in the sera of xenograft-bearing mice. The polyp-associated lymphocytes proliferated and were found to migrate from the xenografts to the spleens of the recipient mice, resulting in a significant splenomegaly. A progressive increase in the volume of the xenografts was observed with little or no evidence of mouse cell infiltration into the human leukocyte antigen-positive human tissue. An average twofold increase in polyp volume was found at 3 months after engraftment.

CONCLUSIONS

The use of innate and adaptive immunodeficient NOD-scid mice homozygous for targeted mutations in the interleukin-2 receptor gamma-chain locus NOD-scid IL2rgamma(null) for establishing xenografts of nondisrupted pieces of human nasal polyp tissues represents a significant improvement over the previously reported xenograft model that used partially immunoincompetent CB17-scid mice as tissue recipients. The absence of the interleukin-2 receptor gamma-chain results in complete elimination of natural killer cell development, as well as severe impairments in T and B cell development. These mice, lacking both innate and adaptive immune responses, significantly improve upon the long-term engraftment of human nasal polyp tissues and provide a model with which to study how nasal polyp-associated lymphocytes and their secreted biologically active products contribute to the histopathology and progression of this chronic inflammatory disease.

Prevalence of human papilloma virus and human herpes virus types 1-7 in human nasal polyposis

This study aimed to investigate the prevalence of human papilloma virus (HPV), herpes simplex virus-1/-2 (HSV-1/-2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpes virus-6/-7 (HHV-6/-7) in 23 human nasal polyps by applying PCR. Two types of control tissues were used: adjacent inferior/middle turbinates from the patients and inferior/middle turbinates from 13 patients undergoing nasal corrective surgery. EBV was the virus most frequently detected (35%), followed by HPV (13%), HSV-1 (9%), and CMV (4%). The CMV-positive polyp was simultaneously positive for HSV-1. HPV was also detected in the adjacent turbinates (4%) and the adjacent middle turbinate (4%) of one of the HPV-positive patients. EBV, HSV, and CMV were not detected in the adjacent turbinates of the EBV-, HSV- or CMV-positive patients. All mucosae were negative for the VZV, HHV-6, and HHV-7. This is the first study to deal with the involvement of a comparable group of viruses in human nasal polyposis. The findings support the theory that the presence of viral EBV markedly influences the pathogenesis of these benign nasal tumors. The low incidence of HPV detected confirms the hypothesis that HPV is correlated with infectious mucosal lesions to a lesser extent than it is with proliferative lesions, such as inverted papilloma. The low incidence of HSV-1 and CMV confirms that these two herpes viruses may play a minor role in the development of nasal polyposis. Double infection with HSV-1 and CMV may also play a minor, though causative, role in nasal polyp development. VZV and HHV-6/-7 do not appear to be involved in the pathogenesis of these mucosal lesions.

Role of human papillomavirus and its detection in potentially malignant and malignant head and neck lesions: updated review

Head and neck malignancies are characterized by a multiphasic and multifactorial etiopathogenesis. Tobacco and alcohol consumption are the most common risk factors for head and neck malignancy. Other factors, including DNA viruses, especially human papilloma virus (HPV), may also play a role in the initiation or development of these lesions. The pathways of HPV transmission in the head and neck mucosal lesions include oral-genital contact, more than one sexual partner and perinatal transmission of HPV to the neonatal child. The increase in prevalence of HPV infection in these lesions may be due to wider acceptance of oral sex among teenagers and adults as this is perceived to be a form of safe sex. The prevalence of HPV in benign lesions as well as malignancies has been assessed by many techniques. Among these, the polymerase chain reaction is the most sensitive method. Review of literature reveals that HPV may be a risk factor for malignancies, but not in all cases. For confirmation of the role of HPV in head and neck squamous cell carcinoma, large population studies are necessary in an assortment of clinical settings. Prophylactic vaccination against high-risk HPV types eventually may prevent a significant number of cervical carcinomas. Of the two vaccines currently available, Gardasil (Merck & Co., Inc.) protects against HPV types 6, 11, 16 and 18, while the other vaccine, Cervarix (GlaxoSmithKline, Rixensart, Belgium) protects against HPV types 16 and 18 only. However, the HPV vaccine has, to the best of our knowledge, not been tried in head and neck carcinoma. The role of HPV in etiopathogenesis, prevalence in benign and malignant lesions of this area and vaccination strategies are briefly reviewed here.

Human papillomaviruses in lymph node neck metastases of head and neck cancers

CONCLUSION

The results of this study corroborate earlier findings that human papillomavirus (HPV)16 is the most prevalent type of HPV in squamous cell carcinomas of the head and neck (SCCHNs) and reinforce a possible influence of HPV on SCCHN progression by showing that the majority of HPV-positive patients harbor HPV16 (or HPV33) both in their primary tumors and in lymph node neck metastases (LNNMs).

OBJECTIVE

HPVs are causally associated with carcinomas of the uterine cervix and have also been linked to a subset of SCCHNs. In order to further investigate the predicted causative role of HPV in SCCHNs, we analyzed pairs of primary tumors and LNNMs or LNNMs alone for the presence of HPV DNA using polymerase chain reaction (PCR).

MATERIAL AND METHODS

DNA was extracted from fresh frozen tissue samples of primary tumors and the corresponding LNNMs of 18 patients and from LNNMs alone in 17 patients. For the detection and typing of HPV, PCR was performed using both type-specific and consensus primer pairs, followed by Southern hybridization and, in selected cases, sequencing of the PCR products.

RESULTS

Of the 35 patients investigated, 22 (63%) were found to have HPV DNA in their tumors: HPV16 DNA in 21 cases and HPV33 in 1. The highest HPV prevalence was detected in tumors of Waldeyer's tonsillar ring (8/9 patients; 89%). Of the 18 patients in whom primary tumors and LNNMs were analyzed, 7 (39%) were HPV-positive in both samples (HPV16, n = 6; HPV33, n = 1), in 3 (17%) the primary tumors were HPV-negative and the LNNMs HPV16-positive and in 1 (5.5%) the primary tumor contained HPV16 and the LNNM was negative. Interestingly, of the 7 patients in whom LNNMs had been detected only several months after diagnosis and treatment of the primary tumors, only 1 showed infection with HPV (HPV33).