Adenocarcinoma of the cervix and adenocarcinoma of the endometrium: distinction with PCR-mediated detection of HPV DNA

Immunohistochemistry in Gynecologic Pathology: An Example-Based Practical Update

CONTEXT

- Immunohistochemical stains are routinely applied in the pathology diagnostic workup of gynecologic lesions. The rapidly expanding repertoire of available markers helps in refining the diagnostic criteria for each disease entity; however, limitations and pitfalls exist.

OBJECTIVE

- To provide a practical, relevant update on the use of immunohistochemistry for commonly encountered differential diagnoses in gynecologic pathology.

DATA SOURCES

- Literature review and authors' diagnostic experience.

CONCLUSIONS

- Immunohistochemistry is a helpful adjunct tool in gynecologic pathology. Although the primary application is in the diagnostic workup, novel prognostic and predictive markers, and immunostains to screen for genetic cancer syndromes, have also been recently introduced in the field.

Human papillomavirus genotype-specific prevalence across the continuum of cervical neoplasia and cancer

BACKGROUND

The New Mexico HPV Pap Registry was established to measure the impact of cervical cancer prevention strategies in the United States. Before widespread human papillomavirus (HPV) vaccine implementation, we established the baseline prevalence for a broad spectrum of HPV genotypes across the continuum of cervical intraepithelial neoplasia (CIN) and cancer.

METHODS

A population-based sample of 6,272 tissue specimens was tested for 37 HPV genotypes. The number of specimens tested within each diagnostic category was: 541 negative, 1,411 CIN grade 1 (CIN1), 2,226 CIN grade 2 (CIN2), and 2,094 CIN grade 3 (CIN3) or greater. Age-specific HPV prevalence was estimated within categories for HPV genotypes targeted by HPV vaccines.

RESULTS

The combined prevalence of HPV genotypes included in the quadrivalent and nonavalent vaccines increased from 15.3% and 29.3% in CIN1 to 58.4% and 83.7% in CIN3, respectively. Prevalence of HPV types included in both vaccines tended to decrease with increasing age for CIN1, CIN2, CIN3, and squamous cell carcinoma (SCC), most notably for CIN3 and SCC. The six most common HPV types in descending order of prevalence were HPV-16, -31, -52, -58, -33, and -39 for CIN3 and HPV-16, -18, -31, -45, -52, and -33 for invasive cancers.

CONCLUSIONS

Health economic modeling of HPV vaccine impact should consider age-specific differences in HPV prevalence.

IMPACT

Population-based HPV prevalence in CIN is not well described, but is requisite for longitudinal assessment of vaccine impact and to understand the effectiveness and performance of various cervical screening strategies in vaccinated and unvaccinated women.

Endometrial carcinomas: a review emphasizing overlapping and distinctive morphological and immunohistochemical features

This review focuses on the most common diagnostic pitfalls and helpful morphologic and immunohistochemical markers in the differential diagnosis between the different subtypes of endometrial carcinomas, including: (1) endometrioid versus serous glandular carcinoma, (2) papillary endometrioid (not otherwise specified, villoglandular and nonvillous variants) versus serous carcinoma, (3) endometrioid carcinoma with spindle cells, hyalinization, and heterologous components versus malignant mixed müllerian tumor, (4) high-grade endometrioid versus serous carcinoma, (5) high-grade endometrioid carcinoma versus dedifferentiated or undifferentiated carcinoma, (6) endometrioid carcinoma with clear cells versus clear cell carcinoma, (7) clear cell versus serous carcinoma, (8) undifferentiated versus neuroendocrine carcinoma, (9) carcinoma of mixed cell types versus carcinoma with ambiguous features or variant morphology, (10) Lynch syndrome-related endometrial carcinomas, (11) high-grade or undifferentiated carcinoma versus nonepithelial uterine tumors. As carcinomas in the endometrium are not always primary, this review also discusses the differential diagnosis between endometrial carcinomas and other gynecological malignancies such as endocervical (glandular) and ovarian/peritoneal serous carcinoma, as well as with extra-gynecologic metastases (mainly breast and colon).

Detection of HPV-DNA by a PCR-based method in formalin-fixed, paraffin-embedded tissue from rare endocervical carcinoma types

High-risk human papilloma virus (HPV) seems to play a role in the pathogenesis of cervical squamous neoplasia and adenocarcinomas of the mucinous and endometrioid cell types. Cervical serous, clear cell, and small cell carcinomas differ from the conventional endocervical adenocarcinoma in their clinical characteristics. The data on the role of HPV in their pathogenesis are limited. In this study, we examined the presence of high-risk HPV-DNA in rare types of cervical carcinoma using polymerase chain reaction-based test. In-house cervical serous, clear cell, and small cell carcinoma cases accessioned between 2000 and 2008 were tested for HPV by polymerase chain reaction amplification of DNA extracted from deparaffinized sections using Roche AMPLICOR HPV Amplification Detection and Control Kits. The kit detects all 13 high-risk HPV-DNA genotypes. The positive cut-off point for AMPLICOR HPV Test was A450 = 0.2. We identified 4 serous, 3 clear cell, 1 mixed clear cell and serous, and 5 small cell carcinomas. High-risk HPV-DNA tested positive in 3 out of 4 serous carcinomas, 2 out of 3 cervical clear cell carcinomas, and all 5 cases of small cell carcinoma and the mixed cell type. Our report documents HPV status in a series of archival unusual types of adenocarcinoma of the uterine cervix. It suggests a robust association between high-risk HPV and these rare subtypes. Despite their unique clinical setting and morphologic appearance, the majority of these tumors likely share a common HPV-mediated carcinogenic pathway. Our observation is particularly significant in cervical cancer prevention as we enter the HPV vaccination era.

Human papillomavirus in endometrial adenocarcinomas: infectious agent or a mere "passenger"?

Aims. To investigate the possible association of human papillomavirus (HPV) with endometrial hyperplasias and neoplasia. Does HPV play any role in the initiation or prognosis of endometrial adenocarcinomas? Methods. Twenty-five endometrial adenocarcinomas of the endometrioid cell type, with and without squamous differentiation, and twenty-four endometrial hyperplasias of various forms (simple, complex, and atypical) were analyzed for the presence of type 16 and 18 HPV by the polymerase chain reaction (PCR). The results were related to histopathological features of the tumour, and the patients' age, and prognosis. Results. Six of 25 endometrial adenocarcinomas were HPV 16-positive (24%), and 5 of 25 (20%) were HPV 18-positive. Simple endometrial hyperplasias was associated somewhat more commonly with HPV 16 and 18 (2/8 and 1/8 cases, resp.) than hyperplasias progressing to endometrial adenocarcinomas, namely, atypical endometrial hyperplasia (1/8 and 0/8 cases, resp.). None of the positive cases in the series, whether hyperplastic or neoplastic, demonstrated cytological evidence of HPV infection. There was no relation between HPV-positive cases and squamous differentiation, depth of myometrial invasion, lymphatic involvement, lymphocytic response, patients' age, or prognosis. Conclusion. It appears that the presence of HPV in the endometrium, as detected by PCR, does not play any role in the initiation or prognosis of endometrial adenocarcinoma.

P16INK4a overexpression independent of Human Papilloma Virus (HPV) infection in rare subtypes of endometrial carcinomas

In the current study, we evaluated p16 expression in rare subtypes of endometrial carcinomas, whose HPV status has been previously examined in order to establish the role of this protein in their pathogenesis. These rare subtypes of endometrial carcinomas are primary squamous endometrial carcinoma (ESCC), endometrial mucinous microglandular adenocarcinoma (EMMA), and endometrial transitional cell carcinoma (ETCC). All tissues, obtained at the time of hysterectomy, were fixed in 10% phosphate-buffered formalin and embedded in paraffin. Serial sections were made for hematoxylin and eosin staining and for immunohistochemistry. Although a previous PCR study has demonstrated that none of these neoplasms showed any signal for HPV DNA, these malignancies did display immunoreactivity for P16(INK4a). In ESCC, P16(INK4a) immunoreactivity was diffuse in 100% of neoplastic cells. In two cases of EMMA, positivity for P16INK4a was zonal. In ETCC, scattered cells were positive for P16INK4a protein. These findings suggest that alteration of p16 could play an etiologic role, without any association to HPV infections, in these rare endometrial carcinomas. However, in our view, other cases of these rare malignancies should be investigated in order to confirm this hypothesis.

Human papillomavirus localization in cervical adenocarcinoma and adenosquamous carcinoma using in situ polymerase chain reaction: review of the literature of human papillomavirus detection in these carcinomas

Many studies have suggested that human papillomavirus (HPV) infection plays an important role in the carcinogenesis of the cervical adenocarcinoma. However, the prevalence of HPV infection in cervical adenocarcinoma and adenosquamous carcinoma varies among the studies. Cervical adenocarcinoma (24 cases) and adenosquamous carcinoma (16 cases), including the underlying non-neoplastic epithelium were examined for HPV-DNA using in situ polymerase chain reaction (PCR), which enabled visualization of the localization on a glass slide. In adenocarcinoma, HPV-DNA was found in 13 cases (54%) and in eight cases in underlying non-neoplastic epithelium, resulting in a total of 21 positive cases (88%). In adenosquamous carcinoma, HPV-DNA was detected in 12 cases (75%) and and the HPV-DNA localization of each component was pure adenocarcinoma, 28.6%; mixed, 54.5%; and pure squamous cell carcinoma, 83.3%. In the underlying non-neoplastic epithelium, HPV-DNA was found more frequently in the squamous epithelium (73.3%) than the cervical glands (6.3%). In conclusion, HPV-DNA was detected in 54% of adenocarcinoma, and the rate was elevated by HPV localization in the underlying non-neoplastic epithelium. HPV infection in the underlying squamous epithelium might be related to the carcinogenesis, even in cervical adenocarcinoma. HPV-DNA localization was different in each component of adenosquamous carcinoma.

Detection of high-risk human papillomavirus (HPV) DNA by Hybrid Capture II in women referred due to atypical glandular cells in the primary screening

We assessed the detection of high-risk human papillomavirus DNA (HPV-DNA) in women examined by a second Pap smear due to atypical glandular cells (AGC) detected in their screening Pap smear. In 91 women included in the study, a second Pap smear was taken and HPV-DNA test was performed using Hybrid Capture II (HC II). The second Pap smear showed no abnormalities in 28 (31%) cases, ACG in 17 (19%) cases, and high-grade squamous intraepithelial lesions (HSIL) or worse in 24 (26%). HC II test was positive in 36% of the cases. Considering the second Pap smear diagnosis, HPV-DNA was detected in 87% of the women with HSIL, 100% of women with in situ adenocarcinoma, and only in 11% of the women with no abnormalities. The use of the second Pap smear combined with HPV-DNA may improve the management of women with AGC in the primary screening.

Human papillomavirus DNA detection and histological findings in women referred for atypical glandular cells or adenocarcinoma in situ in their Pap smears

OBJECTIVE

To evaluate the association between high-risk human papillomavirus (HPV) DNA detection and histological diagnosis in women referred for atypical glandular cells (AGC) or adenocarcinoma in situ (AIS) at Pap smear.

METHODS

In this cross-sectional study, 146 women referred for AGC (124), AGC with high-grade squamous intraepithelial lesion (HSIL) (15), or AIS (7) were tested for HPV DNA using Hybrid Capture II (HC II). All women underwent colposcopic examination, and cervical biopsy was performed for 95 patients. Fifty-one women referred due to AGC with normal colposcopy and normal second Pap smear were scheduled for control visits every 4 months.

RESULTS

The overall prevalence of HPV DNA was 38%. HPV DNA was detected in 93% of the women with HSIL associated with AGC and in 71% of women with AIS Pap smear, being significantly higher when compared with the prevalence (29%) in women with AGC alone. Forty-five women (30.8%) had clinically significant histological lesions (CIN 2 or worse). High-risk HPV DNA was detected in only 16% of the women without significant abnormalities in biopsy, in contrast to 96% of those who had CIN 2 or CIN 3 and 75% of women with AIS. Eighty-five percent of women with invasive cervical carcinoma (squamous or adenocarcinoma) tested positive for HPV DNA. HPV DNA detection was significantly associated with histological diagnosis of CIN 2 or worse, with an odds ratio (OR) = 51.8 (95% CI 14.3-199.9).

CONCLUSION

HPV DNA detection was strongly associated with the severity of cervical lesion (CIN 2 or worse) in women referred for AGC or AIS in their Pap smear. These data implicate the use of HPV testing in triage of women with AGC Pap smears.

Distinction of Endocervical and Endometrial Adenocarcinomas

Determining the origin of uterine adenocarcinomas can be difficult in biopsy and curettage specimens because the morphologic spectrum of endocervical and endometrial adenocarcinomas overlaps. In hysterectomy specimens, the primary site is often equivocal for tumors that involve the lower uterine segment and endocervix and lack identifiable precursor lesions. Most endocervical adenocarcinomas (ECAs) contain high-risk human papillomavirus (HPV) DNA, whereas endometrial adenocarcinomas (EMAs) rarely do. p16 is an inhibitor ofcyclin-dependent kinases, and overexpression of p16 has been observed in cervical intraepithelial lesions and invasive carcinomas associated with high-risk HPV types. We evaluated the utility of immunohistochemistry for p16 in the distinction of ECAs and EMAs. p16 expression was assessed in 24 unequivocal EMAs and 19 unequivocal ECAs and correlated with HPV DNA detection by in situ hybridization and polymerase chain reaction. These assays were then used to assist in the classification of four lower uterine segment/upper endocervical adenocarcinomas (LUS/EC-A) of equivocal origin. p16 expression was moderate-strong and diffuse in 18 ECAs (median 90% of tumor cells positive, range 90%-100%), and weak and diffuse in one. Fourteen of these were positive for HPV DNA, whereas 5 lacked detectable HPV DNA by in situ hybridization; one of these 5 was positive by polymerase chain reaction. In contrast, EMAs displayed weaker staining with patchy distribution (median 30% of tumor cells positive, range 5%-70%) and none contained HPV DNA by in situ hybridization. Two LUS/EC-As, which were positive for HPV, exhibited strong, diffuse p16 expression, consistent with endocervical origin of the tumors. The remaining 2 LUS/EC-As showed patchy p16 staining and did not contain detectable HPV DNA, consistent with the endometrial origin of the tumors. The p16 expression pattern can distinguish ECAs from EMAs. Compared with HPV DNA detection by in situ hybridization, p16 immunohistochemistry appears to be a more sensitive and easier to perform method for distinguishing ECAs from EMAs, can be used to assist in the classification of LUS/EC-As of equivocal origin, and should be evaluated for its utility in the prospective classification of uterine adenocarcinomas in curettage specimens prior to hysterectomy.

The value of HPV DNA typing in the distinction between adenocarcinoma of endocervical and endometrial origin

AIMS

Distinguishing between adenocarcinomas of endocervical and endometrial origin histologically can be difficult, particularly in small biopsies. Most endocervical adenocarcinomas contain human papillomavirus (HPV) deoxyribonucleic acid (DNA) of 'high-risk' (HR) types, whereas this has not been consistently demonstrated in endometrial adenocarcinomas. The aim of this study was to determine whether HPV DNA testing could aid in this differential diagnosis.

METHODS

The frequency of HPV DNA in paraffin-embedded tissue samples from 50 endocervical and 50 endometrial adenocarcinomas was investigated using polymerase chain reaction (PCR) amplification techniques involving (i) a screening HPV test followed by HPV DNA sequencing, and (ii) a test designed to detect HR genotypes 16, 18, 31, 33, 35, 45 and 58. Control specimens included cervical intraepithelial neoplasia (CIN) III lesions, squamous cell carcinomas (SCCs) of the cervix and lung, and colonic adenocarcinomas. Measures to minimise cross-contamination were implemented.

RESULTS

The screening test followed by HPV DNA sequencing had the highest sensitivity. By this test HR HPV DNA was detected in 11 of 11 (100%) cervical intraepithelial neoplasia (CIN III) lesions, nine of 10 (90%) cervical SCCs, none of 10 (0%) colorectal adenocarcinomas and none of 10 (0%) SCCs of the lung. Thirty-nine (78%) endocervical adenocarcinomas contained HR HPV DNA, compared to one (2.0%) endometrial adenocarcinoma.

CONCLUSIONS

The results suggest that HPV DNA testing could be a useful adjunct in distinguishing between endocervical and endometrial adenocarcinomas in curettings or small biopsy specimens.

p16 immunoreactivity may assist in the distinction between endometrial and endocervical adenocarcinoma

The distinction between an endometrial and an endocervical origin of an adenocarcinoma may be difficult, especially with small biopsy specimens or when tumor is present in both endometrial and cervical specimens. Previous studies have investigated the value of antibodies such as carcinoembryonic antigen, estrogen receptor, and vimentin in making this distinction. We investigated the value of p16 immunohistochemistry for distinguishing between an endometrial and an endocervical origin of an adenocarcinoma. Cases included in the study were endometrial adenocarcinomas of endometrioid type (n=29) and cervical adenocarcinomas of endocervical type (n=23). Cases were scored on a scale from 0 to 5 depending on the percentage of positive tumor cells: 0 (negative or occasional cells positive); 1 (<5% cells positive); 2 (5-20% cells positive); 3 (21-50% cells positive); 4 (51-99% cells positive); 5 (100% cells positive). Twenty-two of 23 (96%) endocervical adenocarcinomas were scored 5; the other was scored 0. The numbers of endometrial adenocarcinomas with scores of 0 to 5, respectively, were 1, 7, 4, 9, 5, and 3. Most primary endocervical adenocarcinomas were characterized by strong, diffuse positivity of 100% of cells with p16. Endometrial adenocarcinomas are usually positive, but positivity is generally focal and commonly involves <50% of cells. However, occasional endometrial adenocarcinomas exhibit 100% positivity. Diffuse, strong positivity with p16 suggests an endocervical rather than an endometrial origin of an adenocarcinoma. When there is morphological doubt this antibody may be of value as part of a panel for ascertaining the origin of an adenocarcinoma. Diffuse, strong positivity with p16 in endocervical adenocarcinomas is likely caused by inactivation of the retinoblastoma protein by the E7 human papillomavirus oncoprotein, which acts as a p16 transcript repressor.

Symposium part IV: investigative approaches to endocervical pathology

There is continuing interest in the study of adenocarcinoma of the cervix and its precursors because of its increase in incidence, both absolute and relative, to squamous neoplasia and the complexity of benign glandular lesions with which endocervical neoplasia may be confused. Investigative techniques may be applied as aids to diagnosis, as prognostic markers, and to further our understanding of etiopathogenesis. This article focuses on recent developments in the four areas of epithelial glycoproteins, molecular markers, cell proliferation markers, and human papillomaviruses as applied to endocervical pathology. Although immunohistochemistry remains dominant, a wide range of other techniques is discussed.

Hormone receptor immunohistochemistry and human papillomavirus in situ hybridization are useful for distinguishing endocervical and endometrial adenocarcinomas

Determining the origin of uterine adenocarcinomas can be difficult in biopsy and curettage specimens because the morphologic spectrum of endocervical and endometrial adenocarcinomas overlaps. In addition, in hysterectomy specimens the primary site is often equivocal for tumors that involve predominantly the lower uterine segment and endocervix and lack identifiable precursor lesions. We assessed the value of immunohistochemistry for estrogen and progesterone receptors and in situ hybridization for human papillomavirus DNA detection in making this clinically relevant distinction. We evaluated a set of 48 adenocarcinomas of unequivocal origin (24 endocervical carcinomas and 24 endometrial endometrioid carcinomas without cervical extension) and then tested seven lower uterine segment/endocervical carcinomas of equivocal origin to determine whether patterns established in the initial set would permit definitive assignment of primary site for the equivocal set. Only one (4.2%) of 24 endocervical carcinomas was positive for both estrogen receptor and progesterone receptor, whereas 18 (75%) of 24 endometrial carcinomas were positive for estrogen receptor and 23 (95.8%) of 24 endometrial carcinomas were positive for progesterone receptor (p <0.001, chi2 test). Human papillomavirus DNA was detected in 16 (66.7%) of 24 endocervical carcinomas and in none of 24 endometrial carcinomas (p <0.001, chi2 test). Of the seven tumors of equivocal origin, five could be definitively classified as either endocervical or endometrial in origin based on their demonstration of a characteristic profile with these assays (either estrogen receptor/progesterone receptor-negative/human papillomavirus-positive, consistent with endocervical origin or estrogen receptor/progesterone receptor-positive/human papillomavirus-negative, consistent with endometrial origin). We conclude that hormone receptor immunohistochemistry and human papillomavirus in situ hybridization are useful for distinguishing endocervical and endometrial adenocarcinomas. The clinical utility of these techniques should be evaluated in studies that include curettage and biopsy specimens.

Endometrioid carcinoma of the uterine corpus: a review of its pathology with emphasis on recent advances and problematic aspects

This review considers the pathologic features of endometrioid carcinoma of the uterine corpus, which accounts for approximately 80% of endometrial adenocarcinomas, with an emphasis on its histologic features, recent advances, and problematic aspects. In addition to typical endometrioid carcinoma, the variants of endometrioid carcinoma covered include secretory carcinoma, villoglandular endometrioid carcinoma, endometrioid carcinoma with small nonvillous papillae, endometrioid carcinomas with microglandular and sertoliform patterns, and endometrioid carcinomas with metaplastic changes. These changes include a variety of different appearances of squamous epithelia (ranging from mature and keratinizing to immature with only subtle evidence of a squamous nature), clear cells, surface changes resembling syncytial metaplasia or microglandular hyperplasia, ciliated cells, oxyphilic cells, and spindled epithelial cells (sarcomatoid carcinoma). The last is one of several variants that may cause a biphasic appearance, all of which should be distinguished from the malignant müllerian mixed tumor. Rare findings in endometrioid carcinomas include hyalinization, psammoma bodies, and foci of stromal metaplasia such as osteoid. Unusual growth patterns of endometrioid carcinomas include involvement of adenomyosis, the "diffusely" infiltrating pattern of myoinvasion, and a previously unemphasized pattern of myoinvasion with "pinched off" glands that may be cystic or have a pseudovascular appearance, often with a myxoid stromal reaction. Other aspects of endometrioid carcinoma discussed are its immunoprofile, grading, cervical involvement (including a hitherto undescribed "burrowing" pattern of extension within the cervix that can result in underdiagnosis of stage IIB disease), carcinoma arising in the lower uterine segment, carcinoma arising in polyps and adenomyomas, carcinoma in young women, tamoxifen-related carcinoma, associated ovarian endometrioid carcinoma, and peritoneal keratin granulomas. Finally, the differential diagnosis of endometrioid carcinoma is briefly considered with a section on benign mimics, including curettage-related changes, menstrual changes, adenomyosis-related problems, metaplastic changes, atypical polypoid adenomyoma, radiation atypia, and papillary proliferations, and a section on metastatic colonic carcinoma.

Human papillomavirus type 16 is detected in transitional cell carcinomas and squamotransitional cell carcinomas of the cervix and endometrium

BACKGROUND

The etiologic role of human papillomavirus (HPV) in a variety of squamous neoplasms, including malignant and premalignant lesions of the cervix, is well established. The presence of HPV, predominantly HPV types 16 and 18, in adenocarcinomas of the endometrium has also been reported, although less commonly. Although rare, transitional cell carcinoma (TCC) in the female genital tract, including such sites as the cervix, endometrium, and ovary, has been described. HPV, however, has not been previously studied in TCC of the female genital tract, the etiology of which is uncertain.

METHODS

Eight cases of primary TCC of the endometrium and six cases of primary TCC of the cervix were retrieved from the files of the Armed Forces Institute of Pathology and the University of Texas Southwestern Medical Center. Slides stained with hematoxylin and eosin were reviewed, and tumor tissue was obtained and analyzed for the presence of HPV types 6, 11, 16, 18, 31, and 33 by polymerase chain reaction (PCR).

RESULTS

HPV was detected by PCR in 4 of 6 TCCs of the cervix (67%) and in 2 of 8 TCCs of the endometrium (25%), using HPV general primers and specific primers to HPV type 16. PCR for HPV using specific primers to HPV types 6 and 11, 18, 31, and 33 were negative in all cases.

CONCLUSIONS

The results of this study demonstrated that HPV type 16 was present in a proportion of primary TCCs of the cervix and endometrium. These findings support the hypothesis that these rare neoplasms are similar, with regard to risk factors, to the more commonly occurring squamous cell carcinomas of the cervix, and suggest that HPV may play an etiologic role in at least a proportion of these tumors.