Detection of human papillomavirus DNA in formalin-fixed tissues by in situ hybridization after amplification by polymerase chain reaction.

The authors describe the detection of human papillomavirus (HPV) 16 DNA in paraffin-embedded, formalin-fixed tissues of cervical squamous intraepithelial lesions (SILs) by in situ hybridization after amplification by the polymerase chain reaction (PCR). Using conventional in situ hybridization and a biotin-labeled probe, variable numbers of superficial cells and none of the basal cells in the SILs showed detectable HPV 16 DNA. When the in situ assay was done after amplification, increased numbers of superficial cells had detectable HPV DNA, and the hybridization signal was much more intense. HPV DNA was also detected in basal and parabasal cells at the site of the lesion whereas not detectable in directly adjacent, normal squamous epithelium. Amplified HPV DNA was demonstrated in formalin-fixed SiHa cells using a biotin-labeled probe, demonstrating the ability to detect one copy of HPV 16 DNA. This technique should allow for direct visualization in cells of other DNA sequences of low copy number from achival specimens otherwise undetectable by conventional in situ hybridization analysis.     

Detection and localization of human papillomavirus in penile condylomas and squamous cell carcinomas using in situ hybridization with biotinylated DNA viral probes

Human papillomavirus (HPV) has been previously demonstrated in male genital neoplasms using Southern blot hybridization (SBH) and in situ hybridization with radiolabeled probes (ISH-R). In this study we used in situ hybridization with biotinylated DNA viral probes (ISH-B), a technique that can be applied to routinely collected and processed tissue. Thirty cases of exophytic penile condyloma acuminatum and nine cases of invasive squamous cell carcinoma of the penis were examined for the presence of HPV using ISH-B for HPV types 6, 11, 16, 18, 31, and 33. HPV DNA was found in 25 of 30 (83%) penile condylomas; HPV type 6 in 13 (43%); and HPV type 11 in 12 (40%). Slight cross-reactivity between HPV types 6 and 11 was noted. None of the condyloma cases was positive for HPV types 16, 18, 31, or 33. One of the nine patients with squamous cell carcinoma of the penis was positive for HPV 16. In situ hybridization with biotinylated DNA viral probes is a highly sensitive method for detecting and localizing HPV in penile condylomas. This method, however, may not be as sensitive as SBH for detecting HPV in invasive penile squamous cell carcinomas.     

Detection of human papillomavirus DNA in genital lesions by using a modified commercially available in situ hybridization assay.

A modified, commercially available DNA-DNA in situ hybridization test that uses biotinylated probes for the identification of human papillomavirus (HPV) DNA types 6/11, 16/18, and 31/33/35 was evaluated. HPV DNA was detected in 314 of 787 (40%) histologically abnormal genital biopsy specimens by using the ViraType in situ assay (Life Technologies, Gaithersburg, Md.), in which the hybridization time was increased from 2 to 16 h. Ninety percent of positive condyloma acuminata specimens contained HPV type 6/11 DNA. The prevalences of HPV DNA for cervical intraepithelial neoplasia I, II, and III lesions by this in situ hybridization test were 42, 54, and 55%, respectively. The combined prevalence of HPV type 16/18 and 31/33/35 DNAs increased with the severity of the lesion, while the prevalence of type 6/11 DNA decreased. HPV type 6/11 DNA was found only in 1 of 16 (6%) positive cervical intraepithelial neoplasia III specimens. HPV type 16/18 and 31/33/35 DNA was detected in 11 of 16 (69%) and 4 of 16 (25%) in situ hybridization-positive cervical intraepithelial neoplasia III specimens, respectively. Thus, the observation that certain "higher-risk" HPV genotypes are associated with upper-grade cervical precancer lesions was confirmed by this commercial hybridization system. In general, the assay was found to be well suited for use in the clinical laboratory. The ViraType in situ procedure modified for a longer hybridization time may be helpful in identifying lesions containing higher-risk HPV strains.     

Penile/anal condylomas and squamous cell cancer

Summary Acuminate condylomas from the penis (n=17) and anus (six cases), three anal/penile giant condylomas, anal Bowen's disease (four cases), and intraanal squamous cell carcinomas with associated condylomatous changes (10 cases) including two verrucous carcinoma were studied for human papillomavirus (HPV) infections with nick translated, biotinylated cDNA probes for HPV 6, 11, 16 and 18. In addition, six cases of flat white penile lesions designated as lichen sclerosus et atrophicus were examined.Reannealed complementary DNA strands were detected in situ with either immunoenzyme or immunogold protocols.The in situ hybridizations resulted in 1/6 positive penile lichenoid lesions, 12/17 positive penile acuminate condylomas, 6/6 positive anal acuminate condylomas (including two condylomas with cellular atypias), 2/3 positive giant condylomas, 1/4 positive anal bowenoid lesions, and 4/10 positive keratinized squamous cell carcinomas, two of them being verrucous carcinomas. All penile/anal condylomas and two giant condylomas harboured HPV 6 and/or 11 DNA.The five positive carcinomas (carcinoma in situ/invasive cancer) contained HPV 6 and/or 11 in two cases (including the verrucous carcinomas), and HPV 16 and/or 18 in three cases (one carcinoma in situ, two invasive carcinomas).Recurrent malignancies were seen in one case to harbour the same HPV type as the primary lesions (HPV 16). In one particular patient, a double infection with HPV 16 and HPV 18 was demonstrated in distantly located malignant tumours. Our study confirms the restrictions and the value of non-isotopic hybridization methods applied to archival tissues, and extends the knowledge on the presence and distribution of HPV infections at anogenital sites.This study was supported by the Deutsche Forschungsgemeinschaft (Lo 285/2-4) and the Hamburger Stiftung zur Förderung der Krebsbekämpfung     

两种检测头颈部鳞状细胞癌HPV16/18感染状态方法的对比

 目的 比较荧光定量PCR法（RT-PCR）和原位杂交法检测头颈部鳞状细胞癌中HPV（HPV）16/18亚型感染的差异。方法 采用RT-PCR法和原位杂交法对78例头颈部鳞状细胞癌患者的肿瘤组织进行HPV感染状态的检测,评价两种方法的一致性。结果 RT-PCR法检测到62.8%的头颈部鳞癌组织中含有HPV16/18 DNA。原位杂交法检测到47.4%的肿瘤组织中有HPV16DNA。用RT-PCR方法,唇、口腔、口咽及下咽的HPV16/18DNA阳性率分别为33.3%、66.67%、70%和57.14%;用原位杂交方法,唇、口腔、口咽、下咽的HPV16 DNA阳性率分别为33.3%、43.8%、60.0%和57.1%。总体上,两种方法检测HPV16/18DNA具有较高一致性（Kappa=0.595,P<0.001）。 结论 RT-PCR和原位杂交法检测HPV16/18DNA结果的一致性较高。     

Human papillomavirus DNA in anal carcinomas. Comparison of in situ and dot blot hybridization.

Because the sensitivities of individual hybridization techniques differ considerably, their role in accounting for the published frequencies of human papillomavirus (HPV) DNA in anal squamous cell carcinomas, ranging from 0 to 61%, must be investigated. With the use of biotinylated probes to HPV 6, 11, 16, 18, and 33, three hybridization techniques were performed on the same paraffin-embedded tissue blocks selected from 13 cases of anal squamous cell carcinoma. HPV DNA was detected in 0%, 62%, and 85% of cases with the use of in situ hybridization with horseradish peroxidase, in situ hybridization with alkaline phosphatase, and dot blot hybridization, respectively. By dot blot hybridization, 69% had HPV 16/6 and 15% had HPV 6/11. An HPV DNA frequency range of 0-85% in the same group of tumors with the use of three hybridization techniques indicates the influential role of the method on HPV DNA prevalences. HPV DNA was identified regardless of patient gender or type of squamous cell carcinoma. The presence of HPV 16 in 82% of the positive cases in supportive evidence of the carcinogenic role of the HPV in anal squamous cell carcinoma.     

Detection of human papillomavirus DNA in squamous bronchial metaplasia and squamous cell carcinomas of the lung by in situ hybridization using biotinylated probes in paraffin-embedded specimens

We examined a series of paraffin-embedded tissue specimens from 10 cases of squamous bronchial metaplasia and 33 cases of squamous cell carcinoma of the lung for histologic characteristics and for the presence and typing of human papillomavirus (HPV) by molecular in situ hybridization with biotinylated probes types 6, 11, 16 and 18 under stringent conditions (temperature, 19 degrees C). Fourteen of these lesions (32.5%) showed typical condylomatous histologic changes. Human papillomavirus DNA was present in seven (16%) specimens. Type 6 HPV DNA was detected in one of the squamous bronchial metaplasia cases. In six of the squamous cell carcinomas cases (18%), HPV DNA was identified (type 18, three cases; type 16, one case; type 11, one case; and type 6, one case); one of the squamous cell carcinoma specimens contained both HPV types 16 and 18. Our data confirm the presence of HPV DNA in squamous metaplastic bronchial mucosa and epidermoid lung carcinoma on paraffin-embedded tissues. This suggests that an HPV infection with benign or potentially oncogenic HPV types could be associated not only with genital tumors, but also with bronchial and lung tumors. The role of HPV DNA in the process of malignancy conversion is not yet known; HPV DNA could possibly be a cocarcinogenic factor. In situ hybridization with biotinylated probes is a useful and appropriate method of retrospective analysis of HPV DNA sequences in routinely paraffin-embedded lesions. It may be used to identify patients at risk of more serious or possibly malignant progression.     

HPV typing of cervical squamous lesions by in situ HPV DNA hybridization: Influence of HPV type and therapy on the follow-up of low-grade squamous cervical disease

Papanicolaou (Pap)-stained cervical specimens from 160 squamous lesions were processed for the detection of human papillomavirus (HPV) DNA by an in situ hybridization (ISH) assay. Three biotinylated HPV DNA probes were employed, each containing HPV genotypes 6/11, HPV genotypes 16/18, or HPV genotypes 31/35/51. The HPV etiology of 86 lesions was ascertained (53.8%). In 74 out of 135 (58.8%) HPV-typed low-grade squamous intraepithelial lesions (SILs), HPV 6/11 was found in nine (6.6%), HPV 16/18 in 46 (34.2%), and HPV31/35/51 in 19 lesions (14.1%); in 11 out of 18 HPV-typed high-grade SILs (61.1%), seven lesions (38.9%) were typed for HPV 16/18 and four (22.2%) for HPV 31/35/51. Of seven invasive carcinomas, only one (14.3%) reacted with the HPV 16/18 DNA probe. A cohort of 124 low-grade SILs was followed cytologically for a year. The results of this study are discussed in light of HPV type association and therapy. Diagn Cytopathol 1994; 11:28–32. © 1994 Wiley-Liss, Inc.     

Detection of human papillomavirus DNA on routine Papanicolaou's smears by in situ hybridization with the use of biotinylated probes.

Specific human papillomavirus (HPV) types have been implicated as playing a major role in the development of cervical neoplasias. HPV DNA types usually have been identified by nucleic acid hybridization assays with the use of radiolabeled probes. These techniques are sensitive and specific but are not suitable for large-scale clinical use. To detect specific HPV DNAs simply and rapidly, in situ hybridization (ISH) with the use of biotinylated HPV DNA 6/11 and 16/18 probes was done on destained Papanicolaou's (Pap) smears from 545 patients. All smears showed koilocytotic changes. HPV DNAs were demonstrated not only in cervical intraepithelial neoplasia (CIN) and atypia, but also in squamous cells with minimal nuclear changes (karyomegaly) and perinuclear halos. HPV DNA 16/18 was detected in 52% of the smears with CIN I, 44% of those with CIN II and III, 19% of those with atypia, and 4% of the minimal changes. HPV DNA 6/11 was detected in 27% of the smears with CIN I, 27% of those with atypia, and 6% of the minimal changes. HPV DNAs were also detected in smears without koilocytotic changes. Thus, ISH with the use of biotinylated probes can serve as an adjunct to Pap smears in detecting HPV infection.     

In situ hybridization analysis of HPV 16 DNA sequences in early cervical neoplasia

The authors examined 18 cervical intraepithelial neoplasms (CIN) for the presence of human papillomavirus (HPV) DNA sequences by Southern blot hybridization and DNA-DNA in situ hybridizations for HPV DNA sequences and compared the epithelial distribution of HPV 16 DNA sequences with HPV 6/11 sequences in selected condylomas. Fifteen of the 18 CIN lesions contained HPV 16 DNA as determined by Southern blot hybridization. With the use of biotinylated HPV 16 DNA probes, 10 of the 18 were positive by in situ hybridization, 9 of which were also positive by Southern blot hybridization. In situ hybridization to HPV 16 probes was found primarily in areas of CIN which contained either maturation or koilocytotic atypia, although in two cases hybridizing sequences were detected in superficial cells from epithelium with no discernible maturation. Staining in both condylomas and CIN lesions varied in distribution and intensity. However, in some CIN lesions staining from cell to cell varied considerably. This greater variability in staining appeared to correlate with greater morphologic variations which characterize CIN, and which may influence greater variation in HPV DNA replication. Thus, some differences in patterns of hybridization for HPV DNA between CIN and condylomas may be explained by morphologic differences in the two classes of lesions. Differences in viral gene expression between condylomas and CIN and their relationship to morphologic findings remain to be clarified.     

Detection of human papillomavirus in skin and genital lesions of renal allograft recipients by in situ hybridization

Renal allograft recipients have an increased incidence of malignancy including squamous carcinoma of cervix and skin. There is growing evidence that human papillomavirus (HPV) has a part to play in malignant transformation at these sites. We have previously identified HPV DNA in the skin and genital lesions of such patients by dot and Southern blotting. In situ hybridization studies, using biotinylated DNA probes for HPV 4, 5 and 8 in skin lesions and 6, 11. 16 and 18 in genital lesions, were performed on tissues derived from the same group of patients. In the cutaneous lesions, only 25% of the specimens probed were found to contain virus by in situ hybridization; 60% of these specimens were found to harbour virus by dot and Southern blotting. In situ hybridization revealed HPV 16 and/or 18 in 86% of the genital lesions probed.     

Sensitivity of in situ hybridization techniques using biotin- and 35S-labeled human papillomavirus (HPV) DNA probes

In order to evaluate the sensitivity of our modified in situ DNA hybridization technique using biotinylated probes, formalin fixed, paraffin embedded biopsies from 20 cervical lesions known to contain human papillomavirus (HPV) DNA were re-examined by the technique using both 35S-labeled- and biotinylated HPV DNA probes. The probe concentrations as well as the detection limits of biotin probing were screened by spotting known amounts of HPV 16 DNA on nylon filter, and allowed to hybridize with biotinylated HPV 16 DNA probe. By this method, 4 pg of HPV 16 DNA could be detected using a probe concentration of 0.2 micrograms/ml. HPV DNA could be demonstrated in all 20 biopsies with both hybridization techniques. However, signals in subrabasal cells were detected more frequently with biotin- than with 35S-labeled probes. Additional experiments were performed using three cervical cancer cell lines (with known copy numbers of HPV DNA), to assess the detection limits of HPV infections by the in situ hybridization techniques. The CaSki cells (500-600 HPV 16 copies/cell) were unequivocally positive with both labelling systems. HeLa cells (10-50 HPV 18 copies/cell) were positive with the biotin probing in 10/10 smears, as compared to 7/10 smears when 35S-labeled probes were used. Radioactive probing was inferior to biotinylated probing in detecting the signals in SiHa cells (1-2 HPV 16 copies/cell). This is because even weak background signals could mask true positive signals when 35S-labeled probes are used. In contrast, no background is generated with the biotinylated probes, detected with streptavidin-biotinylated alkaline phosphatase complex. In situ hybridization with biotinylated DNA probes is as sensitive as techniques using 35S-labeled probes for detecting HPV infections in routine cervical biopsies or smears.     

Influence of fixation on human papillomavirus DNA detection in frozen and embedded paraffin lesions by in situ hybridization with biotinylated probes.

Series of frozen or paraffin-embedded tissues from various body sites, taken from non-immunosuppressed or immunosuppressed patients with persistent papilloma lesions were examined for the presence of group specific antigen from human papillomavirus (HPV) by indirect immunofluorescence or HPV DNA by in situ hybridization with biotinylated probes. We have shown that it is possible to detect HPV DNA after fixation of tissues in neutral formalin, Bouin's or Baker's solution. However, the sensitivity was reduced as compared to frozen tissues. The HPV DNA was detected in nuclei of heavily infected epithelial cells such as plantar or hand warts or in dispersed cells containing high copy numbers of HPV DNA from lesions such as squamous cell carcinomas or keratoacanthomas. In premalignant or malignant lesions of both immunosuppressed or non-immunosuppressed patients, HPV DNA was rarely detected after fixation. HPV types commonly described for skin and genital samples were identified in non-immunosuppressed patients, whereas in transplant recipients oncogenic HPV type 16 was identified in benign warts as well as in premalignant or malignant lesions. Positive reactions with several HPV types were more frequent in lesions from grafted patients than from the normal population. Virus antigen was detectable more frequently in frozen sections than in fixed tissues. Our findings indicate that in situ hybridization is an appropriate and rapid technique to study the presence of HPV infection. However, numerous controls are needed to avoid misinterpretations.     

Detection of HPV16 and 18 by in situ hybridization in precancerous and cancerous lesions of cervix

Fifty cervical biopsies from women with preinvasive and invasive malignancies of uterine cervix and ten normal cervical biopsies were examined for the presence of human papilloma virus (HPV) 16 and 18 DNA sequences by in situ hybridization (ISH) method with biotinylated DNA probes. The overall positivity of HPV DNA was 48% (24/50). The positivity of HPV 16 DNA for low grade squamous intraepithelial lesion (LSIL), high grade squamous intraepithelial lesions (HSIL) and squamous cell carcinoma (SCC) were 33.33%, 45.45%, 42.30% respectively. The positivity for HPV 18 DNA for LSIL, HSIL and SCC were 0%, 18.18%, 30.76% respectively. Two cases of cervical adenocarcinomas showed positivity for HPV 18 DNA only.     

Histological characteristics of human papilloma-virus-positive and -negative invasive and in situ squamous cell tumours of the penis

A high prevalence of cervical cancer associated high-risk types of human papillomavirus (hrHPV) has been demonstrated in premalignant and invasive squamous cell lesions of the penis, but large studies correlating histological characteristics with HPV status are few in number. Tumour tissues from 145 patients with invasive ( n  = 116) or in situ ( n  = 29) penile squamous cell carcinoma were subjected to systematic histological evaluation and were PCR-tested for 14 hrHPV types and 23 low-risk HPV types. Around half (52%) of invasive and nine-tenths (90%) of in situ lesions were positive for an hrHPV type, of which HPV 16 was by far the predominant type (91% of hrHPV-positive lesions). In relation to histological characteristics, hrHPV positivity was statistically significantly more common in high-grade tumours, lesions dominated by small tumour cells, lesions with a high number of multinucleated cells and mitoses, and lesions with a small amount of parakeratosis. In conclusion, about half of invasive penile squamous carcinomas in this study were hrHPV-positive, most notably to HPV 16, and probably arose through in situ lesions whereas the other half of invasive penile lesions appeared to be unrelated to hrHPV. A number of histological characteristics differed significantly between hrHPV-positive and -negative invasive penile carcinomas.     

Vulvar carcinomas: search for sequences homologous to human papillomavirus and herpes simplex virus DNA

Ten cases of intraepithelial carcinoma, five with Bowenoid features and five with early invasion, and ten cases of invasive vulvar carcinoma were examined by in situ hybridization and Southern blot analysis using DNA probes for human papillomavirus (HPV) types 6, 11, 16, 18 and 31. HPV DNA was detected in 90% of the intraepithelial cases and in 10% of the invasive cases. All positive cases showed the presence of DNA of HPV type 16. The cases with intraepithelial lesions revealed a strong correlation between the presence of HPV type 16 DNA, cigarette smoking habit, other potential cofactors such as herpes simplex (HSV) DNA sequences and the use of contraceptive drugs, and clinicopathologic features of Bowen's type in situ squamous cell carcinoma. Similar associations were not observed among the cases with invasive disease. While HPV-16 is associated with differentiated Bowenoid type vulvar intraepithelial neoplasia, which appears to be the most common form of early carcinoma of the vulva, the same association was not seen with respect to advanced vulvar invasive squamous cell carcinoma.     

应用基因芯片诊断宫颈石蜡组织样本中人乳头状瘤病毒感染及其临床意义

目的探讨应用基因芯片检测宫颈石蜡组织标本中人乳头状瘤病毒（HPV）感染的可能性及其临床意义。方法收集解放军总医院诊断为宫颈鳞状上皮病变的石蜡组织标本40例,其中宫颈浸润性鳞癌18例,宫颈上皮内瘤变（CIN）Ⅲ12例,CINⅠ4例,CINⅡ6例。从组织中提取DNA后采用基因芯片检测23种常见HPV基因亚型,即PCR扩增后产物在基因芯片上进行杂交。同时选用10例经基因芯片检测16型和18型基因阳性的宫颈鳞癌的石蜡组织切片做原位杂交。基因芯片检测结果与部分原位杂交结果进行比较并分析。结果基因芯片检测的18例宫颈鳞癌HPV高危亚型均为阳性（100％）,其中1例为混合阳性;12例CINⅢ中11例为高危亚型阳性（91．7％）,1例阴性;6例CINⅡ的宫颈病变中高危型5例阳性,低危型1例阳性;4例CINⅠ中有2例低危型阳性、2例阴性;宫颈鳞癌和CINⅢ组与CINⅠ和Ⅱ组比较,差异有统计学意义（U=80．0,P〈0．01）。10例宫颈鳞癌基因芯片HPV16型和18型阳性组织中,原位杂交同型探针6例检测显示阳性。结论HPV基因芯片技术可用于检测多种亚型,特异性强,敏感性高,对HPV感染亚型的鉴别及宫颈癌的预防和治疗具有重要意义。     

肺鳞癌人乳头状瘤病毒感染的原位杂交检测和观察

经多重多聚酶链反应，检测４９例肺鳞癌中发现７例人乳头瘤病毒阳性的肿瘤组织，采用生物素标记ＨＰＶＤＮＡ探针，进行原位杂交检测，结果发现在５例肿瘤组织中显示ＨＰＶＤＮＡ阳性信号，其中ＨＰＶ１１型阳性３例；ＨＰＶ１６例阳性１例；１例为ＨＰＶ１１例和１６型均阳性。原杂交ＨＰＶＤＮＡ阳性信号，大多位于凹空样肿瘤细胞或低分化鳞癌细胞的核内，分子生物学研究表明ＨＰＶ感染可能与部分鳞有关。     

In situ hybridization study on human papillomavirus DNA expression in benign and malignant squamous lesions of the esophagus.

Histologic changes suggesting HPV infection are occasionally found adjacent to squamous cell carcinoma or in squamous papilloma of the esophagus, but the relationship between HPV infection and benign and malignant squamous lesions of the esophagus is not yet dear. The aim of this study was to examine the role of HPV in squamous lesions of the esophagus. Microscopic examination with emphasis on HPV infection was done on 15 cases of squamous cell carcinoma and 26 cases of squamous papilloma. In situ hybridization technique for wide-spectrum HPV probe was performed on 35 endoscopically biopsied esophageal tissues. Among the histologic parameters suggesting HPV infection, acanthosis was the most frequent finding: 100.0% in benign and malignant esophageal lesions, and koilocytosis and intraepithelial capillary loops were the second (92.7%).: Dyskeratosis, basal cell hyperplasia and bi- or multinucleation were 52.3%, 44.0% and 34.1% in frequency, respectively. On in situ hybridization study, the HPV DNA expression rates of 10 squamous cell carcinomas with evidence of HPV infection and 15 carcinomas without evidence of HPV infection were 60.0% and 33.3%, respectively. In contrast to the carcinoma cases, only one (10.0%) of 10 squamous papillomas revealed positive signal. In conclusion, HPV infection is strongly associated with squamous cell carcinoma, but the causal relation of HPV to squamous papilloma is inconspicous.     

Human papillomavirus DNA determination of anal condylomata, dysplasias, and squamous carcinomas with in situ hybridization

Infection with types 6, 11, 16, and 18 of the human papillomavirus (HPV) is associated with condylomatous, dysplastic, or carcinomatous changes in the genital tract. Emerging evidence suggests that a similar series of lesions develops in the anal canal after exposure to the same HPV types. In situ hybridization was performed with the use of biotinylated DNA probes to HPV 6, 11, 16, and 18, so as to determine the frequency of HPV DNA in 45 perianal and/or anal condylomata, 6 anal intraepithelial neoplasias, and 13 anal squamous cell carcinomas. Of the 33 perianal and/or anal condylomata in which HPV DNA was detected, 13 contained HPV 6 and 11, 12 HPV 6, 7 HPV 11, and 1 HPV 6, 11, and 18. Two of four severe anal dysplasias contained HPV 16, whereas one case each of mild and moderate anal dysplasia contained HPV 6. No HPV DNA was detected in the anal squamous cell carcinomas. The study demonstrated the presence of HPV DNA in 73% of condylomata and 67% of anal dysplasias. The observations suggest that the cloacogenically derived anal epithelium is susceptible to infection by the same HPV types as infect the similarly derived epithelium of the lower female genital tract and that these HPV types result in some similar lesions, i.e., condylomata and dysplasias in both sites. A role in the genesis of anal cancer was not found in this study.