Human papillomavirus (HPV) DNA in esophageal precancer lesions and squamous cell carcinomas from China

Human papillomavirus type 16 DNA in esophageal carcinomas from Alaska Natives

The possible etiological role of human papillomavirus (HPV) in esophageal carcinogenesis was evaluated in Alaska Natives in whom the incidence of esophageal cancer is 1.3 and 3.8 times higher than in US Caucasian men and women, respectively. Fixed paraffin-embedded esophageal tissues from 32 cases of squamous-cell carcinoma (SCC) and 3 cases of adenocarcinoma (AC) diagnosed between 1957 and 1988 were analyzed by polymerase chain reaction (PCR) and in situ hybridization for HPV DNA sequences. Detection of the human beta-globin gene by PCR was used as a control for sufficiency of DNA and its potential for amplification in the tissue samples. Twenty-five of the tumor tissues were considered adequate for PCR analyses; HPV DNA was detected in 10 of 22 SCCs and was not found in 3 ACs. Seven of the 10 HPV-positive tissues contained sequences from the E6 gene of HPV type 16. Koilocytosis, an epithelial change consistent with HPV infection, was found in 80% of the esophageal squamous-cell tumors with HPV DNA and in 75% of those without HPV DNA. The detection of amplifiable cellular DNA was related to recentness of diagnosis; however, the detection of HPV DNA within amplifiable specimens was not related to recentness of diagnosis. A 413-bp sequence from the L1 open reading frame of HPV 16 from esophageal tissue of 2 patients was identical to sequences previously identified in cervical cells from other Alaska Natives. Our results provide molecular evidence of HPV infection, especially type 16, in archival esophageal cancer tissues from 45% of those patients whose specimens contain adequate DNA for PCR analysis.

Human papillomavirus (HPV) in head and neck cancer. An association of HPV 16 with squamous cell carcinoma of Waldeyer's tonsillar ring

BACKGROUND

Certain strains of human papillomavirus (HPV) have been shown to be etiologically related to the development of uterine cervical and other genital cancers, but their role in the development of malignancies at other sites is less well established. Previous studies have shown HPV DNA in tumors of the head and neck, but its prevalence has varied depending on the detection methods and the types of tumor and/or tissue examined. This study was undertaken to estimate the frequency of HPV DNA in squamous cell carcinoma (SCC) at different sites of the esophagus, head and neck and to compare the clinical behavior of HPV positive and negative tumors.

METHODS

DNA was extracted from frozen tissue of 167 SCCs of the esophagus, head and neck. The DNA was screened for HPV sequences by polymerase chain reaction with two sets of consensus primers, one to a conserved region in the L1 gene (MY09/ MY11) and the other to a conserved region in the E1 open reading frame (IU/IWDO). The products were run on agarose gels, detected by ethidium bromide staining, and then the gels were subjected to Southern blot analysis and hybridized with probes specific to HPV 6, 16, and 18. All tumors found to be HPV positive with the consensus primers were amplified with type specific primers, and in selected cases the presence of HPV DNA was confirmed by restriction enzyme digestion of the tumor DNA with conventional Southern blot analysis.

RESULTS

Overall, HPV sequences were found in 25 of 167 tumors (15%), but HPV was detected most frequently in tumors in Waldeyer's tonsillar ring. In that area, 9 of 15 (60%) were HPV positive. No HPV DNA was detected in 11 esophageal SCCs, 7 tumors of the pharynx/hypopharynx, or 6 pyriform sinus carcinomas. HPV DNA was detected in the following tumor sites: 1 of 28 (3.6%) in the larynx, 1 of 10 (10%) in the oral cavity, 5 of 39 (12.8%) in the tongue, 2 of 15 (13.5%) in the floor of the mouth, 3 of 21 (14.3%) supraglottic, and 1 of 7 (14.3%) in the lip. A high incidence of HPV DNA was also found in metastatic tumors located in cervical lymph nodes for which no primary site was clinically identified (3 of 8, 37.5%). With respect to age, gender, and tobacco and alcohol consumption, analysis of clinical data obtained by retrospective review showed no difference between patients with HPV DNA in their tumors and those in which no HPV was detected. However, HPV positive patients had larger tumors (P = 0.09) and a higher incidence of lymph node metastasis (P = 0.003). In spite of the higher stage of disease at presentation in HPV positive patients, there was no significant difference in 3-year survival rates between HPV positive patients and HPV negative patients (43.1% vs. 48.8%, respectively). Median follow-up was 27 months.

CONCLUSIONS

In the head and neck, HPV-associated SCC had site specificity with the viral DNA frequently found in tumors in Waldeyer's tonsillar ring. Patients with HPV positive tumors presented with a higher stage of disease than patients with HPV negative tumors, but there was no significant difference in the 3-year survival rates between these two groups of patients.

Detection of human papillomavirus in esophageal squamous cell carcinoma

BACKGROUND

Human papillomavirus (HPV) DNA has been identified in esophageal carcinomas. However, the incidence of HPV varies significantly in different geographic locations. In the current study, neoplasms from two separate geographic regions were analyzed for the presence of HPV DNA:

METHODS

One hundred and ten esophageal squamous cell carcinomas, 83 from Beijing, China and 27 from Cincinnati, Ohio, were examined for the presence of HPV DNA: In situ hybridization and polymerase chain reaction (PCR) using both consensus primers for the HPV L1 gene and type specific primers for the E6 gene of HPV types 6, 16, and 18 were performed.

RESULTS

In situ hybridization failed to demonstrate any HPV type (6, 11, 16, 18, 31, 33, or 35) in any tumor specimen. Likewise, PCR using consensus primers for the HPV L1 gene was negative in all samples. Three of the Chinese specimens (4.29%) were positive for HPV using E6 type specific primers. One tumor contained HPV type 6 DNA, whereas the other 2 contained HPV type 16 DNA. One Cincinnati tumor (4.35%) was positive for HPV 16 by type specific primer. None of the specimens contained HPV 18 DNA.

CONCLUSIONS

The incidence of HPV DNA in esophageal carcinoma specimens from Beijing, China and Cincinnati, Ohio is similar. The incidence of HPV in tumors from Beijing is significantly lower than that reported for those from other regions of China where the incidence of esophageal cancer is higher. Thus, although HPV may play a role in esophageal carcinogenesis, this role may be more pronounced in those regions of the world with a high incidence of the disease, and may be less important in areas with moderate or low risks for esophageal cancer.

Detection of human papillomavirus in esophageal squamous cell carcinoma

BACKGROUND

Human papillomavirus (HPV) DNA has been identified in esophageal carcinomas. However, the incidence of HPV varies significantly in different geographic locations. In the current study, neoplasms from two separate geographic regions were analyzed for the presence of HPV DNA:

METHODS

One hundred and ten esophageal squamous cell carcinomas, 83 from Beijing, China and 27 from Cincinnati, Ohio, were examined for the presence of HPV DNA: In situ hybridization and polymerase chain reaction (PCR) using both consensus primers for the HPV L1 gene and type specific primers for the E6 gene of HPV types 6, 16, and 18 were performed.

RESULTS

In situ hybridization failed to demonstrate any HPV type (6, 11, 16, 18, 31, 33, or 35) in any tumor specimen. Likewise, PCR using consensus primers for the HPV L1 gene was negative in all samples. Three of the Chinese specimens (4.29%) were positive for HPV using E6 type specific primers. One tumor contained HPV type 6 DNA, whereas the other 2 contained HPV type 16 DNA. One Cincinnati tumor (4.35%) was positive for HPV 16 by type specific primer. None of the specimens contained HPV 18 DNA.

CONCLUSIONS

The incidence of HPV DNA in esophageal carcinoma specimens from Beijing, China and Cincinnati, Ohio is similar. The incidence of HPV in tumors from Beijing is significantly lower than that reported for those from other regions of China where the incidence of esophageal cancer is higher. Thus, although HPV may play a role in esophageal carcinogenesis, this role may be more pronounced in those regions of the world with a high incidence of the disease, and may be less important in areas with moderate or low risks for esophageal cancer.

Human papillomavirus expression in oral mucosa, premalignant conditions, and squamous cell carcinoma: a retrospective review of the literature

OBJECTIVES

The literature of human papillomavirus detection in normal oral mucosa and oral lesions associated with the dysplastic progression of epithelium was reviewed to help define the role of this virus in the development of oral squamous cell carcinoma.

STUDY DESIGN

All available data from published studies were analyzed by chi-square test for association between the human papillomavirus and age, gender, race, DNA type, location, lesional dysplastic progression, method of detection, tissue preservation, and use of tobacco and alcohol.

RESULTS

Human papillomavirus was identified with increasing frequency in normal oral mucosa (13.5%), benign leukoplakia (14.8%), intraepithelial neoplasia (18.5%), squamous carcinoma (26.2%), and verrucous carcinoma (27%). It was detected in oral squamous cell carcinoma significantly (p < 0.005) more often (37.1%; 122 of 329) in studies that used a high sensitivity assay (polymerase chain reaction) than studies that used moderate sensitivity assays (25.2%; 84 of 334) (e.g., Southern blot hybridization) and low sensitivity assays (16.9%; 61 of 362) (e.g., immunohistochemistry, in situ hybridization). Human papillomavirus DNA was detected significantly more often (p < 0.001) in frozen oral squamous cell carcinoma (51.6%; 115 of 223) than paraffin-embedded tissue (21.7%; 136 of 628). High-risk human papillomaviruses (2, 16, 18) were detected in 81.4% of OSCCs that contained the virus compared with low-risk human papillomavirus genotypes (6, 11) in 17.9% of oral squamous cell carcinoma that contained the human papillomavirus (p < 0.001). In studies that analyzed the use of chemical cofactors, the use of tobacco and alcohol (87.3%) was associated more often with oral squamous cell carcinoma than the presence of human papillomavirus (51.3%), however, the difference was not significant.

CONCLUSION

High-risk human papillomavirus genotypes have a significant association with oral squamous cell carcinoma. However, the presence of this virus in a high proportion of oral normal mucosa makes the virus alone a poor prognosticator of progression to malignancy.

Type 73 human papillomavirus in esophageal squamous cell carcinoma: a novel association

BACKGROUND

Human papillomaviruses (HPVs) commonly cause proliferative lesions of squamous epithelia, and infection with certain HPV types carries a high risk of malignant transformation, especially in the uterine cervix but also at other sites, including the esophagus. We used molecular techniques to detect and type HPV in an in situ squamous cell carcinoma in the esophagus of a 39-year old woman.

METHODS

DNA was extracted from paraffin sections of the esophageal lesion and of the uterine cervix (which was removed several years earlier), and analyzed for HPV by polymerase chain reaction (PCR). Primers complementary to highly conserved regions of the open reading frame of most genital HPVs were used to amplify a approximately 450 base pair product that contained both conserved and divergent regions. The PCR products were hybridized with probes specific for HPV-6, HPV-11, HPV-16, and HPV-18, and with a consensus probe. A conspicuous band in the esophageal sample failed to hybridize with any of the probes. The amplimer was subcloned and sequenced. The sequence was compared with other known HPVs.

RESULTS

The intraepithelial neoplasia in the patient's cervical cone biopsy contained HPV-16. The esophageal lesion contained HPV that did not hybridize with probes for types 6, 11, 16, or 18, but exhibited 98.3% homology with HPV-73.

CONCLUSIONS

Squamous cell carcinoma in situ of the esophagus may be associated with infection by HPV-73.

Absence of human papillomavirus DNA in breast cancer as revealed by polymerase chain reaction

Oncogenic human papillomavirus (HPV) types 16 and 18 commonly associated with cervical cancer are found in many epithelial malignancies at extra-genital sites including breast. The transforming gene products of HPV have also been shown to immortalize breast epithelial cells in vitro. But the findings of HPV DNA in breast carcinoma are found to be contradictory. In the present study fine needle aspirate cell (FNAC) samples from 26 breast cancer patients and four breast tumour biopsies were analysed for the presence of HPV 16 and 18 DNA sequences by both polymerase chain reaction (PCR) and Southern blot hybridization. Of 26 fine needle aspirate cell samples and four breast cancer biopsies, not a single sample was found to be positive by either PCR or Southern blot hybridization. The observation of complete absence of HPV DNA sequences in breast cancer refute the possibility of any role for oncogenic genital HPV types 16 and 18 in the pathogenesis of breast cancer.

The molecular biology of esophageal carcinoma

There have been many new developments in our understanding of esophageal carcinoma biology over the past several years. Information regarding both of the major forms of this disease, adenocarcinoma and squamous cell carcinoma, has accumulated in conjunction with data on precursor conditions such as Barrett's esophagus. Some of the most interesting and promising findings have included aneuploidy (abnormal DNA content), amplification and overexpression of proto-oncogenes, loss of heterozygosity at multiple chromosomal loci, and tumor suppressor gene inactivation. Of particular importance is mutation and deletion involving the tumor suppressor gene p53, but abnormalities in the retinoblastoma, deleted in colon cancer, and adenomatous polyposis coli genes have been described as well. Recently, two important cancer pathways implicated in the genesis of multiple tumor types have also been inculpated in esophageal carcinogenesis: the cyclin kinase inhibitor cascade and the DNA mismatch repair process. Alterations in the p16 and p15 cyclin kinase inhibitors, including point mutation and homozygous deletion, have been reported in primary esophageal tumors and/or tumor-derived cell lines. Microsatellite instability, the hallmark of DNA mismatch repair defects, has been detected in esophageal cancers, particularly those associated with Barrett's metaplasia (where it may represent an early event). Further developments in the field of molecular carcinogenesis of esophageal malignancies promise to yield improvements in the early detection, prognostic categorization, and perhaps eventual gene-based therapy of this deadly disease.

Papillomatosis of the esophagus

Esophageal papillomas are rare. Both local irritation as by gastroesophageal reflux and infections with human papillomavirus (HPV) have been implicated as etiological factors. We here describe a 28-year-old female patient with massive esophageal papillomatosis. The clinical course has been mild, with signs of regression after a 3 1/2-year observation period. An extensive evaluation showed no predisposing diseases, and test results for HPV using sensitive methods were negative despite histological features suggesting virus infection and concomitant pharyngeal papillomas that are known to be caused by HPV. This case underlines the incomplete understanding of the etiology of this disease.

Absence of human papillomavirus DNA detected by polymerase chain reaction in French patients with esophageal carcinoma

BACKGROUND & AIMS

Recent studies have suggested that esophageal human papillomavirus infection could be a risk factor for esophageal squamous cell carcinoma. The aim of this study was to evaluate the prevalence of human papillomavirus DNA sequences in the esophagus of French patients with esophageal squamous cell carcinoma.

METHODS

Multiplex polymerase chain reactions with consensus primers directed to the L1 gene or specific primers for human papillomavirus types 6, 11, 16, 18, 31, and 33 directed to E6 gene (40 cycles followed by restriction mapping of the amplified products) were used to determine the presence of human papillomavirus DNA sequences in esophageal squamous cell carcinoma (n = 75), normal adjacent mucosa (n = 49), and metastatic lymphadenopathies (n = 5). As an internal control, a target located in the embryonic myosin heavy-chain gene was used in each reaction.

RESULTS

Human papillomavirus DNA sequences could not be detected in any of the tumoral samples, the normal adjacent mucosa, or the metastatic lymphadenopathies.

CONCLUSIONS

Human papillomavirus seems not to be implicated in esophageal carcinogenesis, at least in French patients, because the viral genomes are not associated with esophageal squamous cell carcinomas.

High prevalence of human papillomavirus in squamous cell carcinoma and matched normal esophageal mucosa: assessment by polymerase chain reaction

BACKGROUND

Studies using DNA technology have reported the presence of human papillomavirus (HPV) DNA in esophageal carcinomas, suggesting that it could play a role in the pathogenesis of this tumor. In the present study, in addition to DNA from neoplasms, normal mucosa was screened for viral DNA, assuming that this would increase HPV detection substantially.

METHODS

Seventeen patients with esophageal carcinoma and 10 control subjects were studied. In 8 of the patients, normal mucosa was also available. Polymerase chain reaction (PCR) was performed using primers for the E6 region of HPV-16 and HPV-18. Koilocytosis, a commonly accepted histopathologic marker of viral infection, was studied, and results were correlated with PCR findings.

RESULTS

DNA from neoplastic lesions was positive for HPV-16 and HPV-18 in 8 of 16 (50%) and in 3 of 16 (18.8%), respectively. When tumor tissue and normal mucosa were available, PCR results were 3 of 8 (37.5%), 5 of 8 (62.5%), and 8 of 8 (100%) for HPV-16, in tumor, normal mucosa, and both. For HPV-18, results were 0 of 8 (0%), 5 of 8 (62.5%), and 5 of 8 (62.5%), respectively. In comparison with tumor samples, positivity in normal mucosa was increased for HPV-18 and for both viral genotypes (P = 0.01). No amplification was obtained in the control group. Koilocytosis was present in 33% of the cases.

CONCLUSIONS

These results suggested a high prevalence of HPV in esophageal carcinoma. The detection rate is significantly higher in normal mucosa specimens, suggesting that infection probably antedates tumor development. Koilocytosis was substantially less sensitive than PCR.

Expression of p53 protein related to human papillomavirus and DNA ploidy in superficial esophageal carcinoma

We examined the p53 protein and human papilloma virus (HPV) by immunohistochemistry and DNA ploidy by cytofluorometry in paraffin-embedded esophageal carcinoma tissue specimens. Sixty-one patients with superficial esophageal carcinoma were operated on between 1983 and 1991 without any prior treatment. Immunostaining of the anti-p53 protein antibody (CM1) was positive in 32 carcinomas (52%). Patients with p53-positive tumors had a poorer outcome than those with p53-negative tumors (P < 0.05). In addition, patients with p53-positive tumors did not have any characteristic site of relapse. Only 5 of the 61 patients (8.2%) had HPV-positive tumors. One of these 5 carcinomas expressed both p53 protein and HPV. Three patients with HPV-positive tumors which had invaded the submucosal layer died of relapse. A determination of DNA ploidy revealed 30 patients with aneuploid tumors, 13 with polyploid tumors and 18 with diploid tumors. The outcome of the patients with aneuploid tumors was worse than that of the patients with diploid tumor (P < 0.05). p53 protein expression was not associated with DNA ploidy; however, the 16 patients who had both p53-positive and aneuploid tumors had a worse prognosis than patients with p53-negative and aneuploid tumors (P < 0.01). These findings suggest that p53 protein expression in conjunction with DNA ploidy may be a useful indicator in evaluating the prognosis of patients with superficial esophageal carcinoma.

Squamous papilloma of the esophagus - a clinicopathologic study of 10 cases and review of the literature

Esophageal squamous papilloma (ESP) is considered to be a rare finding during endoscopy or autopsy. Over a 10 year period, 10 cases were identified among 14,232 patients who were endoscoped in the King Khalid University Hospital (KKUH), Riyadh. The calculated incidence was 0.07%. There were eight males and two females whose ages ranged from 24 to 65 years. The presenting symptoms were mostly dyspepsia and heartburn. All the ESPs were single growth, most of which were located in the lower segment of the esophagus. Immunoperoxidase staining was negative for human papilloma virus in all the tissue samples. It is calculated that ESPs may not be very rare in the Saudi population. Awareness of its occurrence may lead to increasing diagnosis among endoscopy patients.

Human papillomavirus DNA in oesophageal carcinomas in South Africa

Using morphological criteria, the presence of human papillomavirus (HPV) in oesophageal carcinomas has been inferred in patients from Finland and South Africa. However, studies to demonstrate the viral antigen in tissue sections of these tumours have proved disappointing. This study investigates 48 archival oesophageal carcinoma biopsies from South Africa for the presence of HPV DNA using non-isotopic in situ hybridization (NISH) with HPV DNA probes to HPV 6, 11, 16, 18, 31, and 33. HPV DNA sequences were detected in 25/48 (52 per cent) oesophageal cancers. HPV 16 was present in 84 per cent of the HPV-positive cancers. A NISH type 2 signal pattern (punctate/dot) was present in all HPV-positive tumours. This signal pattern was previously shown to represent integrated HPV DNA within host chromosome. Integrated HPV DNA in oesophageal cancers has also been demonstrated in patients from China and Japan. In addition, the prevalence of HPV DNA in oesophageal cancers from high-risk countries like South Africa (52 per cent) and China (49 per cent) would appear to be consistent.

Human papillomavirus type 16-positive esophageal papilloma at an endoscopic injection sclerotherapy site

Human papillomavirus infection is important for both the development of papilloma and the progression of the papilloma-carcinoma sequence in the cervix, larynx, lung, and colon. Esophageal squamous cell papilloma is rare but important as a possible precancerous lesion. Esophageal papilloma has previously been thought to develop mainly as a result of chemical irritation by chronic gastroesophageal reflux. However, a few recent studies suggested a role for papillomavirus infection in esophageal tumorigenesis, although the exact route of transmission and invasion of the virus has not been fully elucidated. A case of esophageal squamous papilloma at the site of endoscopic injection sclerotherapy (EIS) for varices is reported. Papilloma development was followed up clinically during a 2-year period, and the papilloma was removed by endoscopic mucosal resection. Histological examination of the tissue confirmed the diagnosis of squamous cell papilloma. DNA analysis of the tumor showed integration of papillomavirus type 16 but not types 18 and 33. The surrounding normal mucosa did not contain any of the three virus types. Injury such as ulceration resulting from EIS may have provided a locus susceptible to the viral infection. The clinical course after EIS should be monitored carefully to detect papilloma formation.

Detection of human papillomavirus DNA in esophageal squamous cell carcinomas by the polymerase chain reaction using general consensus primers

We studied 40 formalin-fixed, paraffin-embedded esophageal squamous cell carcinomas from a high risk region for this tumor for the presence of human papillomavirus (HPV) DNA by the polymerase chain reaction (PCR). We used two general consensus primers from a highly conserved E1 region of HPV types 6, 11, 16, and 18. Human papillomavirus DNA was detected in 60% (24 of 40) of the cases without relation to the tumor grade. Two lymph node metastases had the same HPV types as the primary tumor. Human papillomavirus types were determined in the 24 HPV-positive cases by Southern blot analysis of amplified DNA. Human papillomavirus type 6 was detected in 50% (12 of 24) of the cases, HPV type 16 in 8% (two of 24), and HPV types 6 and 16 in 17% (four of 24); in 25% (six of 24) of the cases the type was unknown. Human papillomavirus types 11 and 18 were not detected. Esophageal mucosa adjacent to the tumor was studied for morphological changes of HPV effect in 27 cases. Adjacent esophageal mucosa in 16 HPV-positive tumors showed statistically significant (P < .05) koilocytosis in six cases. Papillomatosis was the next most frequent finding in four cases. This study supports the role of HPV in the causation of esophageal squamous cell carcinomas, especially in high risk regions for this tumor.

Frequent mutations of p53 gene in oesophageal squamous cell carcinomas with and without human papillomavirus (HPV) involvement suggest the dominant role of environmental carcinogens in oesophageal carcinogenesis

Epidemiological evidence suggests that alcohol intake, use of tobacco, ingestion of mycotoxins and nitrosamines and nutritional deficiencies are high-risk factors for the development of oesophageal cancer. Similarly, viral infections have been postulated to play a role in some tumours. However, the molecular events underlying the development of oesophageal carcinoma are poorly understood as yet. Loss of p53 tumour-suppressor gene function has been found in different human malignancies, and it can occur in a variety of ways, including gene mutation and interaction with the E6 protein of oncogenic human papillomaviruses (HPVs). Because the oesophageal mucosa is potentially exposed to mutagens and HPVs, we studied DNA samples derived from nine HPV-positive squamous cell carcinomas and 12 HPV-negative tumours. Exons 5-9 of the p53 gene containing phylogenetically conserved domains were examined using the polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) technique. HPV detection was done using DNA in situ hybridisation with biotin-labelled HPV DNA probes. Mutations were detected in eight (38%) out of the 21 cases. Three mutations were found in exons 5/6, three in exon 7 and two in exon 8/9. Six (50%) of the 12 HPV-negative carcinomas showed p53 mutations. Two (22.2%) of the nine HPV-positive carcinomas were found to contain p53 mutations as well; one contained HPV 16 DNA sequences and showed p53 mutation in exon 8/9, and the other was HPV 6/11 positive with the mutation in exon 5/6. Although mutations were more common in HPV-negative tumours (50.0% vs 22.2%), the difference in p53 mutations in HPV-positive and -negative tumours did not reach statistical significance (P = 0.1946). These data indicate that inactivation of the p53 gene is a frequent event in oesophageal squamous cell carcinomas and such an inactivation might be an important molecular pathway for the development of oesophageal cancer. The findings of p53 mutations in HPV-positive oesophageal carcinomas suggest that HPV and p53 mutation were not mutually exclusive events. The presence of frequent mutations of p53 gene in both HPV-positive and -negative oesophageal carcinomas suggests a dominant role of environmental carcinogens in oesophageal carcinogenesis.

Human papillomavirus DNA sequences in esophagus squamous cell carcinoma

BACKGROUND/AIMS

Esophagus squamous cell carcinoma has much geographic variation. A variety of genetic and environmental factors have been implicated in the pathogenesis of esophagus squamous cell carcinoma. This study was undertaken to determine whether the human papillomavirus is present in these tumors.

METHODS

A radioactive nested polymerase chain reaction was used to determine the presence of human papillomavirus in esophagus squamous cell carcinoma DNA and adjacent normal mucosa DNA from different regions of the world. Restriction fragment length polymorphism analysis was used to determine which particular human papillomavirus genotype was present.

RESULTS

Human papillomavirus was identified in 14% of esophageal squamous cell cancer DNA but in none of the adjacent normal mucosa DNA available for some of the samples. Positive samples were found to contain sequences specific for high-risk human papillomaviruses, either types 16 or 18. In addition, a novel human papillomavirus genotype was detected in another 10% of the samples.

CONCLUSIONS

Esophagus squamous cell carcinoma is associated with the expression of human papillomavirus genotypes 16 and 18, which are linked to transformation of squamous epithelial cells. In addition, a novel human papillomavirus genotype that was identified may be associated with pathogenesis in esophagus squamous cell cancer.

Human papillomavirus not found in squamous and large cell lung carcinomas by polymerase chain reaction

BACKGROUND

Human papillomavirus (HPV) has been identified not only in anogenital carcinomas, but also in malignancies of other organs, including bronchogenic carcinomas. Previous studies reporting detection of these viruses in lung cancers used mainly in situ hybridization. The authors applied the polymerase chain reaction (PCR) for investigating the occurrence of HPV in bronchial neoplasms.

METHODS

Formalin fixed, paraffin embedded tissues of 40 squamous and 7 large cell lung cancers were examined. PCR was done with consensus primers, capable of detecting HPV 6, 11, 16, 18, 31, 33, 52b, and 58.

RESULTS

None of the 47 samples contained any of the examined HPV types.

CONCLUSIONS

Because the squamous and large cell cancer cases were found not to be associated with HPV infection, this study does not support the potential role of these viruses in the development of lung cancers.

Squamous cell papillomas of the esophagus: a study of 23 lesions for human papillomavirus by in situ hybridization and the polymerase chain reaction

This study assessed squamous cell papillomas of the human esophagus for the presence of human papillomavirus (HPV) and correlated the results with histological features. Twenty-three lesions obtained by endoscopic biopsy from 17 patients were studied, first by in situ hybridization (ISH) for HPV types 6-11, 16-18, 18, and 31-33-51, and second by the polymerase chain reaction (PCR) with amplification of multiple HPV types and demonstration of amplified product by ethidium bromide staining and Southern blot hybridization for HPV types 6-11, 16, and 18 in each case. Evidence of HPV DNA was found in only one lesion, which showed HPV type 6-11 by ISH and HPV positivity by Southern blotting of the amplified product after the PCR. This case exhibited histological features suggestive of HPV infection, although no morphological changes specific to the lesion were identified. The remaining 22 lesions, including those from cases in which multiple papillomas were present, were negative for HPV. The results show that HPV DNA is frequently not detectable in esophageal squamous cell papillomas, even when highly sensitive techniques are used. These findings are consistent with the hypothesis that other pathogenetic mechanisms, such as mucosal injury and repair, are important in the etiology of these lesions.

Esophageal infections: risk factors, presentation, diagnosis, and treatment

Infections of the esophagus are unusual in the general population and strongly imply immunodeficiency, although immunocompetent individuals are not exempt. HIV infection is predominant among risk factors for infectious esophagitis. For all immunocompromised patients, the most frequently identified esophageal pathogens are Candida, CMV, and HSV. Peculiar to HIV-infected patients are idiopathic esophageal ulcers as well as unusual bacteria and parasites. Patterns of presentation differ with each infecting organism, and clinical features should be used as a guide in achieving a correct diagnosis. For example, a patient with AIDS presenting with esophageal symptoms and thrush, along with abdominal pain, nausea, vomiting, and fever, is unlikely to resolve all symptoms with empiric antifungal therapy alone. Parsimony of diagnosis does not hold among immunodeficient patients in whom concurrent infections are common. Accurate and timely diagnoses are essential as effective treatments are available for particular etiologies. Finally, among immunocompromised patients, all esophageal symptoms are not necessarily due to an infection, and possible diagnoses of pill esophagitis, acid-peptic injury, or structural and functional abnormalities should not be overlooked.

Screening for human papillomavirus infections in esophageal squamous cell carcinomas by in situ hybridization

BACKGROUND

Infections with specific types of human papillomavirus (HPV) have been closely linked with human squamous cell carcinomas, those of the anogenital tract in particular. Increasing number of reports also suggest that HPV infection could be a risk factor for esophageal cancer. However, most of the previous studies on HPV involvement in esophageal carcinomas have included only small numbers of biopsy specimens, thus necessitating additional studies based on extensive series of esophageal samples.

METHODS

A series of 776 biopsy specimens derived from 363 patients who had undergone esophagectomy for squamous cell carcinoma in the high-incidence area of China were analyzed for the presence of HPV DNA by screening and specific typing in situ hybridization with biotinylated HPV DNA probes.

RESULTS

Under low-stringency conditions, 85 (23.4%) tumors were demonstrated to contain HPV DNA: Positive signals were found on the nuclei of cancer cells in 71 (19.6%), in the surrounding epithelial cells with hyperplastic or dysplastic changes in 13 (3.6%), in the cancer cells and the surrounding epithelial cells in 10 (2.8%), and in the resected margins in 1 (0.3%). Thirty-four (40%) of the 85 HPV-positive tumors were shown to contain at least one type of HPV 6, 11, 16, 18, or 30 DNA sequences. HPV 16 was the type found most frequently, occurring in 18.8% of the 85 HPV-positive specimens. In addition to the primary tumors, HPV DNA sequences were found in 12.3% (7 of 57) of the lymph node metastases.

CONCLUSION

The results confirm the previously reported HPV involvement in esophageal squamous cell lesions and implicate HPV as a potential etiologic agent in the multifactorial pathogenesis of esophageal carcinoma.

Human papillomavirus in squamous cell carcinoma of the oesophagus associated with tylosis

Human papillomavirus (HPV) may have a pathogenic role in squamous cell carcinoma of the oesophagus. Tylosis, an inherited thickening of the skin of the palms and soles, was associated with a high risk of developing squamous cell carcinoma of the oesophagus among members of a large family in Liverpool. The resected carcinomas of the oesophagus was examined from four such patients with DNA probes to HPV types 6,11,16,18,31,33 and 35 using in situ hybridisation under conditions of high stringency. No reaction was detected. The oesophageal biopsy specimens from 10 tylotic subjects without carcinoma were also examined. No HPV DNA was detected. It is concluded that there is no evidence that HPV infection has a role in the development of squamous cell carcinoma of the oesophagus in tylosis.

Prognostic significance of human papillomavirus genomes (type-16, -18) and aberrant expression of p53 protein in human esophageal cancer

The presence and distribution of human papillomavirus (HPV) DNA or of increased expression of the p53 protein were determined in 71 patients with esophageal squamous-cell carcinoma (SCC) by in situ hybridization with biotinylated DNA probes for HPV-16, -18, -31 and -33, and immunohistochemical techniques using antibody to p53 protein. Of 71 patients from Kochi prefecture, 24 (Group I) were positive for HPV DNA, including 10 for HPV type-16 and 14 for HPV type-18; in contrast, none were positive for HPV-31 or -33. Of the remaining 47 patients, 24 (Group II) showed positive nuclear staining in cancer cells with p53 antibody. The group of 23 patients with neither HPV nor p53 expression (Group III) had a significantly better survival rate than Group I or II. These results suggest that HPV-16 and -18 may play a role in the pathogenesis of esophageal SCC, particularly with regard to its striking geographical distribution; that esophageal cancers do occur in the absence of HPV infection when over-expression of p53 is present; and that the presence of HPV infection and over-expression of p53 may each be a factor indicating a relatively poor prognosis.

Cervical (Pap) smear. New directions

This article reports the historic background leading to the introduction of cervical smears as a tool in the detection of precancerous changes in the uterine cervix. The false-negative error rate in the primary screening process is discussed and illustrated by data recently compiled from this laboratory. Rescreening of approximately 25% of cervical smears yielded an error screening rate of approximately 5% of precancerous lesions and cancer of the uterine cervix. The total false-negative screening error rate was much higher but was unknown and should be determined by additional studies. The reasons for the false-negative screening errors are discussed. Some of the proposed remedies, particularly screening of the entire population for human papillomavirus infection, are judged to be unacceptable because of the high prevalence of this virus in well women and because the biologic events linking the presence of viral DNA with the development of precancerous lesions are unknown. Screening assistance with the help of a newly developed interactive machine, combining image analysis with a neural net was promising as a tool in quality control.

Cytologic diagnosis of oral, esophageal, and peripheral lung cancer

Oral cavity. Most carcinomas in situ of the oral cavity present as red or pink lesions that do not have a keratinized surface. Scrapings of such lesions readily disclose abnormal squamous cells diagnostic of cancer. Scrapings of the keratinized white lesions (so-called leukoplakia) are of no diagnostic value. Dentists, who are most likely to uncover precancerous lesions, are apparently not aware of the diagnostic options based on simple scrape smears. The method is also applicable to follow-up of patients with treated cancer of the oral cavity. Esophagus. Cytologic evaluation of esophageal cancer, initially by washings and subsequently by brushings under endoscopic control, is an established method of diagnosis. The diagnostic results are very good in symptomatic cancer patients and have an accuracy reaching 85-90%. Unfortunately the results of treatment of advanced lesions are very poor, with 5-year survival of only about 5%. Serious efforts at detection of early esophageal cancer started in China in the 1960s, using an abrasive balloon technique which was applied to asymptomatic populations in high risk areas such as Linxian in the Henan province of Central China. The Chinese investigators reported the finding of numerous precancerous lesions of the esophagus classified as carcinoma in situ and as dysplasia. Surgical resection of some of the precursor lesions apparently resulted in a significant drop in the rate of invasive carcinoma, although the statistical results were not convincingly presented. The balloon technique has been tested by us and by others in South Africa and in Transkei, confirming its efficacy in the diagnosis of early esophageal cancer. Peripheral lung. Sputum and bronchial brush cytology may uncover bronchogenic carcinoma in situ and early invasive cancers located in the primary or secondary bronchi. Small, peripheral lung lesions usually do not shed cells in sputum or brushings, and their discovery is usually based on roentgenologic finding. The identity of such lesions can be confirmed in most cases by a transcutaneous aspiration. Most of the peripheral malignant lesions are small adenocarcinomas or epidermoid carcinomas, both resectable by routine surgical procedures. Less commonly, oat cell carcinomas may be observed and these lesions should not be treated by surgery. Benign lesions such as granulomatous inflammation and fungal infections may also be identified by aspiration techniques. The prognosis of the resectable carcinomas varies with their size and the presence or absence of regional lymph node metastases.(ABSTRACT TRUNCATED AT 400 WORDS)

Detection of human papillomavirus DNA in esophageal carcinoma in Japan by polymerase chain reaction

BACKGROUND

Human papillomaviruses (HPV) have been implicated strongly in the pathogenesis of human squamous cell carcinomas, especially of anogenital carcinomas. Some pathologic changes of the esophagus may be one of the candidates for HPV etiology, but the role of HPV infections in the carcinogenesis of the esophagus remains to be clarified.

METHODS

To elucidate the association of HPV with carcinogenesis of the esophagus, 45 biopsy samples of esophageal squamous cell carcinomas were examined for the presence of HPV DNA by polymerase chain reaction (PCR). Primers for PCR were (1) consensus primers (CP) for the simultaneous amplification of the E6-E7 regions of cancer-associated HPV types (HPV 16, 18, 31, 33, 52b, and 58), which have been shown to have transforming activities; (2) type-specific primers (SP16, SP18) for the E7 regions of HPV 16 and HPV 18, respectively; and (3) general primers (GP) for the simultaneous amplification of the L1 regions of HPV 6, 11, 16, 18, 31, and 33.

RESULTS

PCR using CP first was done for screening and showed that 3 (6.7%) of 45 specimens contained HPV 16 or HPV 18 DNA, the oncogenic high-risk HPV types. This was confirmed by SP16 and SP18 PCR. However, no HPV DNA was detected by PCR using GP. These results suggested that the HPV DNA detected might be integrated into the cell genome with their transforming genes retained and their late regions deleted.

CONCLUSIONS

Most oncogenic types of HPV (HPV 16 and HPV 18) were detected by PCR in carcinomas of the esophagus. Thus, HPV might play a role, although at a low frequency, in carcinogenesis of the esophagus.

Infectious agents in the etiology of esophageal cancer

Extensive epidemiological and experimental studies have suggested that some chemical agents, nutritional deficiencies, and physical factors are associated with the development of esophageal cancer (EC). Recent evidence also suggests an etiologic role of certain microorganisms in esophageal carcinogenesis either by producing carcinogens or promotors or by acting directly on the host cells. The mutagenic and carcinogenic effects of several fungi and bacteria isolated from the grains and foodstuffs in high-risk areas have been shown by in vitro and in vivo studies. Certain viruses, e.g., human papillomavirus, herpes simplex virus, cytomegalovirus, and Epstein-Barr virus, have been implicated in the pathogenesis of a variety of human cancers, and all of them are known to produce tumors in animals and cell transformation in vitro. These viruses also have been shown to infect the esophageal epithelium. Therefore, although many of the key issues of their mechanisms of action are unclear as yet, they should be considered potential etiologic agents of EC. The present review summarizes the data available on the etiology of EC, emphasizing the current evidence implicating an etiologic role of microorganisms in the pathogenesis of this malignancy.

Human papillomavirus involvement in esophageal precancerous lesions and squamous cell carcinomas as evidenced by microscopy and different DNA techniques

A series of 71 surgically resected esophageal squamous cell carcinomas, including 51 cases of formalin-fixed samples and 20 cases of fresh biopsy specimens derived from the high-incidence area of esophageal cancer in China, were systematically analyzed for the presence of human papillomavirus (HPV) infections by light microscopy, electron microscopy (TEM), in situ DNA hybridization, Southern blot hybridization, and polymerase chain reaction (PCR) techniques. On light microscopy, HPV-suggestive lesions were found in a total of 49.0% (25 of 51) of the specimens, including the flat type (22 of 51) and, less frequently, an inverted one (2 of 51). Of the 51 formalin-fixed, paraffin-embedded specimens, 43.1% (22 of 51) contained HPV DNA sequences by in situ hybridization. Of the positive cases, HPV 6 was present in three (5.9%), HPV 11 in three (5.9%), HPV 16 in eight (15.7%), HPV 18 in six (11.8%), double infections with HPV 11/18 in one (2.0%), and HPV 16/18 in one. In most cases the HPV-positive signals were localized in the hyperplastic and/or dysplastic epithelium adjacent to invasive carcinomas. In two specimens, however, HPV DNA sequences were found in the frankly invasive lesions, one being HPV 6 and the other HPV 18. On TEM, HPV-like particles located in the nuclei of koilocytotic cells were demonstrated in two of the five specimens previously shown to be HPV-positive by in situ hybridization. By means of the PCR technique, all specimens positive for HPV by in situ hybridization also contained amplified HPV sequences. Moreover, three additional samples negative by in situ hybridization were found to contain HPV 11 DNA sequences. Of the 20 DNA samples extracted from the fresh carcinoma samples (containing some surrounding tissues as well) 9 were shown to contain HPV DNA sequences by Southern blot hybridization under low-stringency conditions. Of these, eight samples remained positive when hybridized with the probe cocktail of HPV 11, 16, 18, and 30 DNA under high-stringency conditions. HPV DNA sequences in these carcinoma specimens appeared to be present mainly in an integrated form. The present results confirm the HPV involvement in esophageal squamous cell lesions and suggest that HPV infection might be an important etiologic factor in the pathogenesis of esophageal cancer, most probably acting synergistically with other carcinogenic factors.

The acetic acid test in evaluation of subclinical genital papillomavirus infection: a comparative study on penoscopy, histopathology, virology and scanning electron microscopy findings

OBJECTIVES

To evaluate colposcopic criteria in acetowhite lesions of the penis ("penoscopy") for the diagnosis of subclinical genitoanal papillomavirus infection (GPVI) compared with histopathological criteria of HPV involvement and to various hybridisation assays for HPV DNA detection, and to depict typical lesions by scanning electron microscopy.

DESIGN

The study included 101 randomly selected male partners of females with known GPVI, or with penile symptoms such as itching, burning and dyspareunia who did not exhibit overt genital warts but appeared to be afflicted with acetowhite penile lesions after topical application of 5% acqueous acetic acid. Lesions were judged by penoscopy as either typical, conspicuous or nontypical for underlying HPV infection. Biopsy specimens from 91 men were examined by light microscopy and by either Southern blot (SB), polymerase chain reaction (PCR) and/or in situ hybridisation (ISH) assays for the presence of HPV DNA of the HPV types 6, 11, 16, 18, 31, 33 and 42 (Group A). From another ten men lesions clinically typical for GPVI were also examined topographically by scanning electronic microscopy (Group B).

SETTING

The STD out-patient clinic of the Department of Dermatovenereology of Karolinska Hospital, Stockholm, Sweden.

RESULTS

Group A Seventy eight (86%) of the biopsied lesions met the penoscopy criteria of being either typical of or conspicuous for GVPI. The agreement between penoscopy and histopathology was fairly good, as HPV diagnosis was made by both methods in 56 (62%) of the cases. The reliability of applying strict colposcopic hallmarks was further substantiated by the finding that 55 (60%) of the biopsy specimens taken from penoscopically typical/conspicuous lesions contained HPV DNA. However, there are diagnostic pitfalls for the acetic acid test. Coexistence of an eczematoid reaction with changes indicative of HPV influence was detected in six (7%) of the cases, while an inflammatory response only occurred in 17 (19%) of the specimens. Additional histopathological diagnoses (normal epithelium, lichen sclerosus et atrophicus, balanitis circinata parakeratotica, verruca plana) were established in another eight (9%) of the cases. Among the HPV DNA positive cases, all of the HPV types tested for were detected with the exception of HPV 18. A severe penile intraepithelial neoplasia (PIN III) was revealed in five (5%) of biopsies; HPV 16 was present in two and HPV 42 in one of these biopsy specimens.

GROUP B

Scanning electron microscopy depiction harmonised with the penoscopy findings showing that subclinical GPVI characteristically exhibits a well demarcated, slightly elevated border and that the central area of lesions often displays a "groove" in which the epithelium appears to be thin with protrusions from beneath that probably represent capillaries.

CONCLUSION

Use of the acetic acid test for evaluation of GPVI should be combined with a colposcopic evaluation based on strict topographic hallmarks, followed by a directed biopsy for light microscopic evaluation. We found that the positive predictive value of colposcopy was as high when correlated with histopathological findings (72%) as when virological methods were used, whether HPV DNA hybridisation testing was performed with the well established SB and ISH assays (45%), or by applying the newly introduced and highly sensitive PCR assay as well (71%). False positivity from the acetic acid test occurs and is mainly due to inflammatory conditions but also to the presence of other conditions. Epithelial fissures are evidently associated with some subclinical GPVI lesions and may potentially represent loci minores for infectious stimuli and perhaps facilitate the transmission of some blood-borne STDs. We prose that the term "papillomavirus balanoposthitis" should be used for penile HPV infection associated with inflammatory responses. Our study indicates that PIN III frequently occurs in a subclinical form and may be associated with not only previously identified "high-risk" HPV types such as type 16, but also with the HPV type 42 that has not previously been considered as oncogenic.

Human papillomavirus infection in esophageal squamous-cell carcinoma in western countries

Recent studies have suggested that esophageal HPV infection could be a risk factor for esophageal squamous-cell carcinoma. The aims of our study were to assess the presence of HPV esophageal infection among French patients with esophageal squamous-cell carcinoma and to compare the prevalence of this infection among control patients exposed to similar known risk factors (alcohol and tobacco) and among non-exposed control patients. All patients had the following investigations: serum immunoglobulin level, T-lymphocyte subsets, cutaneous anergy test and endoscopy with biopsies from tumoral and normal areas. Three different methods were used for HPV-infection diagnosis: histological score, in situ hybridization intended for detection of HPV types 6, 11, 16, 18, 31 and 33, and dot blot intended for detection of HPV types 6/11 and 16/18. Five out of 12 patients with esophageal carcinoma had HPV esophageal infection. This infection did not result from impaired immune status. The most frequently observed types are HPV 16/18. None out of 17 exposed controls and only 1 out of 7 nonexposed controls had HPV esophageal infection (p less than 0.01). HPV infection may be implicated in the development of esophageal squamous-cell carcinoma in association with known risk factors.

Squamous papilloma of the esophagus associated with the human papillomavirus

Squamous cell papilloma of the esophagus is a rare lesion involving less than 60 case reports worldwide. These lesions are generally asymptomatic but may at times grow and spread rapidly. One fatality, a result of massive dissemination, has been reported. Until recently, human papillomavirus had not been identified in association with esophageal papillomas. A second case, to the authors' knowledge, of esophageal papillomas associated with human papillomavirus is reported. The virus has been previously shown to be associated with abnormal squamous epithelium in and adjacent to esophageal carcinoma. The virus was identified from biopsy specimens obtained at endoscopy using DNA in situ hybridization techniques. The strain of human papillomavirus identified is similar to those found in the oropharynx and genital tract, raising the possibility of sexual transmission. This case also differs from the previous case report involving the human papillomavirus because of the patient's benign clinical course. Our case serves to highlight differences that are perhaps unique to the human papillomavirus. Multiple papillomas found in a proximal location within the esophagus seem to favor involvement of the human papillomavirus. Isolated lesions located distally appear more characteristic of chronic gastroesophageal reflux as an etiology. The syndrome of squamous cell papillomas involving the esophagus is reviewed in the article.

Effect of chewing Qat on mucosal histology and prevalence of Helicobacter pylori in the oesophagus, stomach and duodenum of Yemeni patients

This investigation was aimed at assessing whether the Yemeni habit of chewing Qat on a regular basis had a significant effect on the upper alimentary tract. Seventy patients with dyspepsia attending Al-Thawra Hospital in Taiz, Yemen Republic were examined by endoscopy. Biopsies were taken from the oesophagus, stomach and duodenum. The patients included 28 who gave a history of daily Qat intake, 21 with less frequent intake and 21 who took none. The only statistically significant finding associated with daily Qat intake was a higher prevalence of duodenal ulcer, particularly in females. However, a strong association was also found between heavy smoking and ulcer, with most ulcer patients who chewed Qat daily being heavy smokers. Chewing Qat was not associated with a higher prevalence of oesophageal dysplasia, making it unlikely to be the cause of the perceived high incidence of oesophageal carcinoma in Yemen. There was a high prevalence of gastric H. pylori colonization (93%) and columnar-lined lower end of oesophagus (18%), as well as low prevalence of intestinal metaplasia of stomach (4%); this was not, however, related to chewing Qat. Further epidemiological and histological studies are needed to assess the significance of these findings in relation to the incidence of oesophageal and gastric carcinoma in Yemen.

Verrucous carcinoma of the leg positive for human papillomavirus DNA 11 and 18: a case report

Human papillomavirus (HPV) types 6 and/or 11 have been associated with benign lesions, while types 16, 18, 31, and 33 are prevalent in malignant lesions. This case report describes the findings in a verrucous carcinoma of the leg, which was examined for HPV types 11, 16, and 18 by in situ DNA hybridization. The lesion gave positive results for HPV subtypes 11 and 18, a combination that, to our knowledge, has not been previously reported in this neoplasm.

Human papillomavirus (HPV) infections and their associations with oral disease

More than 65 distinct types of human papillomavirus (HPV) have been identified to date. Several of the HPV types have been proposed as etiologic agents of squamous cell carcinoma. In the oral cavity, HPVs have been found associated with several benign squamous cell proliferations. Evidence from histology and DNA hybridization studies suggests that HPV is also involved in oral carcinogenesis. It is apparent, however, that substantial amount of confusion exists in the diagnosis of oral HPV infections. The keratotic, papillary lesions in the oral cavity are usually small and easily overlooked. The gross appearance of these viral lesions is not distinct enough to be readily diagnosed by the clinicians. Degenerative changes found on oral mucosa frequently simulate koilocytosis. Thus, caution should be exercised to avoid overdiagnosis of HPV infection in the oral cavity. The present review summarizes the current evidence available on HPV infections in general and on oral HPV infections in particular. The diagnostic techniques available as well as the problems encountered in the distinction of these lesions are also discussed in short.

Human papillomavirus DNA types in squamous cell carcinomas of the head and neck

Previous studies have found variable evidence suggestive of a role for human papillomavirus (HPV) in squamous cell carcinoma of the head and neck. In this study 49 cases of primary verrucous or squamous cell carcinoma from patients referred to a regional medical center were examined initially by Southern blot hybridization to detect HPV types 2, 6, 11, 13, 16, 18, and 32. Approximately 60% of carcinomas from certain head and neck sites, particularly the floor of the mouth, tongue, pharynx, piriform sinus, and larynx, were positive for episomal viral DNA of HPV-6, -11, -16, or -18. HPV DNA was found in some multiple tumors from separate sites of the same patient. Integration of viral DNA into the host cell chromosome was likely in a minority of the positive carcinomas, and no novel HPV DNA types were indicated by the hybridization analyses. Subsequently, DNA remaining from 30 of the carcinomas was examined by a more sensitive polymerase chain reaction amplification assay for DNA of HPV-6, -11, -16, and -18. Twenty-seven of the samples were positive for one or more HPV DNA types, with all positive carcinoma samples containing oncogenic HPV-16 or -18 DNAs. Almost all the patients examined were of the middle to older age group with a history of tobacco use. Although HPV infection of oral mucosa may be a frequent occurrence, a possible role for HPVs in the multifactorial etiology of head and neck carcinogenesis merits further epidemiologic investigation.

Esophageal squamous cell papillomas. Failure to detect human papillomavirus DNA by in situ hybridization and polymerase chain reaction

Squamous cell papilloma of the esophagus has been regarded as a distinct rarity. After having reviewed the files of the Gastrointestinal Endoscopy Unit of our hospital we found 14 patients diagnosed as having an esophageal papilloma on endoscopy of about 18,000 patients during the period 1985-90. On histologic examination of the biopsy specimens 12 cases showed histologic characteristics typical of a squamous cell papilloma (SQP), 1 was a fibroid polyp, and another showed epithelial dysplasia without the features typical of SQP. To assess the role of human papillomavirus (HPV) recently implicated in the etiology of this tumor, we analyzed all specimens for the presence of HPV types 6, 11, 16, and 18 DNA by in situ DNA hybridization (ISH) and polymerase chain reaction (PCR). No viral DNA was found by either ISH or PCR in any of these lesions. The significance of these findings is discussed in relation to the previous evidence presented on HPV involvement in the development of esophageal squamous cell papillomas and in esophageal carcinogenesis.