p53 immunoreactivity in endometrial metaplasia with dysfunctional uterine bleeding

Endometrial Metaplastic/Reactive Changes Coexistent with Endometrial Hyperplasia and Carcinoma: A Morphological and Immunohistochemical Study

The aim of this study was to assess the relationship between endometrial metaplastic/reactive changes (EMRCs) and endometrial neoplastic lesions. Twenty cases of “simple” (without architecture complexity) EMRCs coexistent with endometrial malignant/premalignant lesions, twenty cases of neoplasia-unassociated EMRCs, and eight cases of complex metaplastic lesions were assessed by immunohistochemistry. EMRCs coexisted with endometrioid carcinoma (n = 12), atypical endometrial hyperplasia (n = 3), serous carcinoma (n = 2), and clear cell carcinoma (n = 3). Neoplasia-associated EMRCs showed a mean Ki67 labeling index of 12.6% (range 0–30%); with nuclear atypia in 16/20 (80%) cases; diffuse p16 expression in 15/20 (75%) cases; and heterogeneous ER, PR, and vimentin expression. Compared to the associated neoplasia, EMRCs showed a lower Ki67 expression (p < 0.001) and higher p16 expression (p < 0.001). No EMRC case showed mitotic activity, PTEN loss, MMR deficiency, nuclear β-catenin, p53-mutant pattern, Napsin A, or AMACR expression. No significant differences were found between neoplasia-associated and neoplasia-unassociated EMRCs. Complex metaplastic lesions showed a lower Ki67 expression than EMRCs (p = 0.044) and PTEN loss in 5/8 cases, even in the absence of nuclear atypia. In conclusion, neoplasia-associated simple EMRCs may show evident atypia and a worrisome immunophenotype, but no data support their involvement in endometrial carcinogenesis. Architectural complexity appears as a crucial factor to identify precancerous lesions.

Molecular markers in uterine serous cancer: Correlation between endometrial biopsy and hysterectomy specimens

Objectives

To measure the correlation of molecular biomarkers between biopsy and final pathology specimens in uterine serous cancer (USC) and to establish the overall prevalence of specific biomarkers among subjects with USC.

Methods

Twenty eight patients with a diagnosis of USC and sufficient biopsy and hysterectomy specimens were identified. IHC was used to measure the biomarker status of EGFR, phospho-AKT, ER, PR, Her2/neu, and PTEN in FFPE tissue. The presence or absence of individual biomarkers was then compared between a given subject's diagnostic biopsy specimen and final hysterectomy specimen.

Results

In the cohort identified, average age was 72 and average BMI was 29. 75% of patients had full lymphadenectomy performed. The average time from biopsy to surgery was 33 days (range 9–91 days). The distribution of disease was 61% stage I (n = 17), 14% stage II (n = 4), 22% stage III (n = 6) and 4% stage IV (n = 1). Biopsy and hysterectomy specimens agreed 67% of the time for phospho-AKT, 80% for ER, 73% for PR, 83% for EGFR, 100% for Her2/neu and 95% for PTEN loss.

Conclusions

The measurement of specific biomarkers correlated well between subjects' biopsy and hysterectomy specimens in women with USC as measured by a pathologist using routine clinical techniques. Preoperative diagnostic biopsy may be a useful tool for guiding neoadjuvant targeted therapy in USC.

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Molecular biomarkers can be measured in endometrial biopsy specimens using routine clinical techniques.

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There was 100% correlation between biopsy and hysterectomy specimen staining for Her2/neu.

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Standardization of staining for molecular markers in endometrial cancers has potential to expand treatment options.

Endometrial Glandular Dysplasia: A Newly Defined Precursor Lesion of Uterine Papillary Serous Carcinoma. Part I: Morphologic Features

Dysplastic epithelium frequently bridges the changes between normal epithelium and noninvasive carcinoma. However, such a dysplastic lesion has not been previously described in the development of uterine papillary serous carcinoma (UPSC) or between resting endometrium and serous endometrial intraepithelial carcinoma (EIC), which is composed of indisputably malignant noninvasive cancer cells. In this study, we hypothesize that there is a lesion bridging benign endometrium and serous EIC. Based on current understanding of carcinogenesis in general, the lesion should exhibit dysplastic features that are more atypical than “resting endometrium” but fall short of serous EIC. If the putative dysplastic endometrial lesion exists, it should be highly associated with UPSC rather than uterine endometrioid carcinoma (UEC). We examined the morphologic appearance of the endometrium from 32 uteri with UPSC, 16 with serous EIC, and 60 with UEC. The endometrial dysplastic lesions were identified and their pathologic features were characterized. Immunohistochemical staining with p53 and MIB-1 were performed in all sections containing endometrial dysplastic lesions, serous EICs, and benign areas. In addition, 25 postmenopausal endometrial biopsies including 6 benign resting endometria, 8 dysplastic lesions, and 11 serous EICs were also compared for the level of p53 overexpression and cellular proliferative activity. We found that endometrial dysplastic lesions do exist in the endometrial specimens we speculated and examined. We designate it as endometrial glandular dysplasia (EmGD). EmGD was present in 17 (53%) uteri with UPSC compared with 1 (1.7%) uterus removed for UEC (p = 0.001). EmGD was identified in 12 (75%) of 16 serous EIC uteri. Areas of both EmGD and serous EIC were found in 15 (47%) of the 32 UPSC uteri. Transitions from either EmGD to serous EIC or serous EIC to UPSC were present in 8 (25%) of the UPSC cases. No transitions from EmGD to UPSC were identified in any hysterectomy specimen. EmGD was frequently found in endometrial polyps. There was no statistically significant difference between EmGD in a polyp (48%) and EmGD in nonpolypoid endometrium (52%). The majority of EmGDs were multifocal and involved superficial endometrial glands. However, single glandular involvement and endometrial surface epithelial involvement were also seen. Immunohistochemically, EmGD lesions mostly showed intermediate scores/indices of p53 and MIB-1 in comparison with serous EIC and resting endometrium. EmGD is a morphologically distinct entity, which is commonly and specifically associated with uterine tumors with serous differentiation. EmGD may represent the earliest identifiable morphologic change in the development of UPSC. Characteristics of p53 and MIB-1 immunostains of EmGD may be of diagnostic usage in surgical pathology practice. Recognition of EmGD may provide an opportunity to improve the management of UPSC.

Clear cell carcinomas of the mullerian system: does the pathogenesis vary depending on their nuclear grade and their association with endometriosis? An immunohistochemical analysis

Clear cell carcinomas (CCC) of the mullerian system are considered high grade tumors, but morphologically, the cells of CCC show both low and high grade features. The aims of the current study were to categorize CCC into low and high nuclear grade types, correlate their association with endometriosis, and then observe possible variations in pathogenesis based on their expression of p53 and Ki-67. We studied 41 pure mullerian CCCs and designated each as either a high (HNG) or low (LNG) nuclear grade tumor. Morphologically, 17 (41%) CCCs were LNG and 24 (59%) were HNG. Nine (38%) HNG and 2 (12%) LNG tumors showed positive immunostaining with p53. Endometriosis was associated with 8 (47%) LNG tumors and 8 (33%) HNG CCCs. Of the 11 cases with p53 alteration, 4 (1 LNG and 3 HNG) were associated with endometriosis.

CONCLUSIONS

HNG CCCs, irrespective of their association with endometriosis, have alterations of p53. In general, LNG ovarian and endometrial CCCs, irrespective of their association with endometriosis/adenomyosis, are less likely to show p53 alteration. It appears that mullerian CCCs may have variable pathogenesis depending on their nuclear grade and association with endometriosis. A larger study is needed to validate these findings.

Tubal metaplasia of the endometrium with cytologic atypia: analysis of p53, Ki-67, TERT, and long-term follow-up

Tubal metaplasia of the endometrium may occasionally display cytologic atypia (atypical tubal metaplasia) resembling serous carcinoma or endometrial intraepithelial carcinoma. Although atypical tubal metaplasia is presumed to be reactive or degenerative in etiology, its clinical significance is unknown. In this study, we investigated atypical tubal metaplasia in regard to its immunoexpression of p53, Ki-67, and human telomerase reverse transcriptase (TERT), and its long-term clinical outcome. A total of 63 cases of atypical tubal metaplasia and 200 cases of endometrial samples with typical tubal metaplasia were followed for a mean of 64 and 61 months, respectively. Of the 63 atypical tubal metaplasia cases, formalin-fixed, paraffin-embedded tissue sections from 16 cases were immunostained with antibodies to p53, Ki-67, and TERT. Sections from 13 cases of uterine serous carcinoma were also stained for TERT as control. After long-term follow-up, 5% of patients in the atypical tubal metaplasia group developed hyperplasia without atypia compared with 4% of patients in the control group (P=0.44), whereas 3% in the atypical tubal metaplasia group developed atypical hyperplasia or carcinoma compared with 2% in the control group (P=0.44). p53 immunoreactivity was either focal and weak or negative in all cases of both atypical and typical tubal metaplasia (P>0.05). Ki-67 immunoreactivity was present in 0-5% of cells in 94% of both atypical and typical tubal metaplasia (P>0.05). TERT immunoexpression was absent in all 16 cases of atypical tubal metaplasia, but present in all 13 cases of uterine serous carcinoma (P<0.0001). Our study indicates that atypical tubal metaplasia displays an immunostaining pattern similar to otherwise typical tubal metaplasia of the endometrium, and distinct from uterine serous neoplasms. The presence of atypical tubal metaplasia in endometrial samplings does not increase the risk of developing endometrial hyperplasia or malignancy.

High-Grade Endometrial Carcinomas

High-grade endometrial carcinomas are a heterogeneous group of clinically aggressive tumors. They include FIGO grade 3 endometrioid carcinoma, serous carcinoma, clear cell carcinoma, undifferentiated carcinoma, and malignant mixed Müllerian tumor (MMMT). Epidemiologic, genetic, biologic prognostic and morphologic differences between these entities are striking in prototypic cases, yet substantial overlap exists and diagnostic criteria and therapeutic approaches that account for the group's diversity are currently insufficient. FIGO grade 3 endometrioid carcinoma demonstrates solid, trabecular or nested growth and may resemble poorly differentiated squamous cell carcinoma. Endometrioid glandular differentiation is usually focally present. Serous carcinoma usually displays papillary architecture but glandular and solid patterns may predominate. Tumor cells typically display diffuse and severe atypia. Clear cell carcinoma should be diagnosed by recognizing characteristic papillary or tubulocystic architecture with cuboidal tumor cells showing atypical but uniform nuclei. Cells with clear cytoplasm are frequently but not always present. On the other hand, clear cells may be encountered in endometrioid and serous carcinomas. Immunohistochemical stains for p53, p16, ER, PR, mib-1, hepatocyte nuclear factor 1β and pan-cytokeratin can be helpful in classifying these high-grade carcinomas. They should be used in concert with thorough morphologic examination, as part of a rational panel of markers and only in specific circumstances. Although these tumors may appear clinically and even morphologically similar, demographic and epidemiologic features as well as patterns of spread and treatment modalities differ.

"Surface epithelial changes" in uterine endometrioid carcinoma mimicking micropapillary serous borderline tumor of ovary: report of two cases and review of the literature

We encountered two cases of endometrioid carcinoma of uterus with extensive surface epithelial changes (SECs) mimicking serous borderline tumor (SBT) of the ovary. The first case was a well-differentiated endometrioid carcinoma arising in a background of complex atypical hyperplasia. The second case was moderately-differentiated endometrioid carcinoma with squamous and mucinous differentiation. The SECs comprised of thin microapapillae without hierarchal branching, lined by cuboidal cells with eosinophilic cytoplasm and mild to moderate nuclear atypia. These areas were reminiscent of SBTs of ovary, micropapillary type. This report expands the existing spectrum of SECs. Serous borderline tumor of ovary like surface epithelial changes could be misleading if present in an endometrial biopsy or curettings. Therefore, knowledge of this morphologic variation is important.

Utility of PTEN expression of endometrial "surface epithelial changes" and underlying atypical endometrial hyperplasia

Surface epithelial changes (SECs) have been reported to be associated with endometrial carcinoma in about 49% of cases. They have also been seen to be associated with endometrial hyperplasia. Although morphologically benign, these lesions are considered a marker for underlying malignancy. Their true biologic nature, however, is not known. PTEN has been reported to be altered in endometrial carcinomas and endometrial precancers where no morphologic changes are appreciated. The current study aims to investigate PTEN status in the endometrial SECs. Thirty-two cases of endometrial biopsy are divided into 2 groups: group 1 had 18 cases of SEC and underlying endometrial atypical hyperplasia and group 2 had 14 cases of SEC alone. Four-micron sections were cut from each block and stained with antibodies to PTEN. One section was stained with hematoxylin and eosin to confirm the presence of the area of interest. Positive and negative control slides were run with each batch of staining. All 32 cases were followed for a median period of 54 (range, 21 to 84) months. Overall, PTEN alteration (NULL) was found in 12 of the 32 cases of endometrial samples (37.5%) examined. In group 1, 10 of the 18 cases (56%) of atypical endometrial hyperplasia with "SECs" showed PTEN NULL. Of these 10 cases, 6 (60%) cases showed FIGO grade 1 endometrioid carcinoma in subsequent hysterectomy specimens. Two other cases (20%) had atypical endometrial hyperplasia only. In group 2, two of the 14 (14%) cases of SECs alone showed PTEN NULL phenotype. These 2 patients were followed for 26 and 63 months, respectively, and subsequent endometrial biopsies and pap smears were negative. Of the remaining 12 cases that retained PTEN, 9 cases (75%) were negative when followed for a median of 54 months (range, 21 to 84 mo). SECs seem to be a heterogeneous entity. Presence of PTEN NULL phenotype in SECs and associated endometrial hyperplasia does not necessarily predict an increased incidence of endometrioid carcinoma in subsequent follow-up. However, absence of PTEN NULL phenotype in SECs alone may predict a benign follow-up.

Minimal uterine serous carcinoma: current concepts in diagnosis and prognosis

Uterine serous carcinoma (USC) is an aggressive type of endometrial cancer with a propensity to have extra-uterine spread at diagnosis, in some cases despite limited involvement of the uterus. Serous endometrial intra-epithelial carcinoma (EIC) is a recently recognised entity with the same cytological features and p53 mutations as USC, but it does not demonstrate stromal or myometrial invasion. In addition to representing the putative precursor to USC, the pure form of serous EIC may also be associated with extra-uterine tumour at the time of diagnosis and with risk for recurrence, spread, and eventual death from tumour. Current evidence indicates that serous EIC is a form of minimal USC with behaviour that is stage dependent, thereby necessitating complete surgical staging despite limited disease in the uterus. We review the diagnostic criteria for minimal USC, pitfalls in the differential diagnosis, and discuss a practical approach to evaluating biopsies, polypectomies, or hysterectomies containing minimal USC.

Precursors of Endometrial Clear Cell Carcinoma

The recognition of morphologically identifiable lesions which may confer an increased risk for subsequent development of an invasive malignancy offers an opportunity to investigate and better understand the molecular-genetic etiopathogenesis of the well-developed tumor, and potentially, to administer a therapeutic intervention before its development. In contrast to uterine endometrioid and serous carcinomas, very little is known about the potential precursor lesions of endometrial clear cell carcinoma (ECCC). In our routine practice, we have noted the presence of a spectrum of atypical glandular changes in the endometria adjacent to ECCC or endometrial carcinomas with a clear cell component, which on the basis of current criteria, would not qualify for any specific designation. We hypothesize that these lesions represent the earliest morphologically recognizable precursor lesions of ECCC and systematically characterize their clinicopathologic features herein. Thirty archived cases of pure ECCC (n=14) or mixed endometrial carcinomas with a >10% clear cell component (n=16) were retrieved and the "normal" endometria adjacent to the malignancies were evaluated in detail. Thirty-eight benign uteri and 30 uteri with classic endometrial endometrioid carcinoma (EEC) served as controls. All cases were reviewed in a blinded fashion. Putative precursor lesions (PPL) were searched for and identified microscopically. The lesions were typically isolated glands or surface epithelium (within an otherwise normal endometrial region) that displayed cytoplasmic clarity and/or eosinophilia with varying degrees of nuclear atypia. Twenty-seven (90%) of the 30 cases had at least 1 PPL. In contrast, PPL were identified neither in the benign uteri nor in endometrioid carcinoma control groups (P<0.001). A total of 67 foci of PPL were identified in the 27 cases with an average of 2.5 foci per case. The immunohistochemical expression of p53, mib-1, estrogen receptor (ERs), and progesterone receptor in the benign endometria, ECCC, and the PPL were evaluated on all 27 cases. The mean p53 scores for the benign endometria, PPL, and ECCC were 0, 4.5, and 6.2, respectively. Parallel values for mib-1 were 15%, 45%, and 63%. ER/progesterone receptor indices for benign endometria, PPL, and carcinoma were 90/80, 21.52/4.61, and 11/4, respectively. The PPL described herein have a morphologic and immunophenotypic profile which seems to be distinct from both the benign endometria in which they reside and the adjacent areas of ECCC. The high frequency of association of these lesions with ECCC, their frequent occurrence as isolated lesions within otherwise "benign-appearing" endometria, and their continuous spectrum of nuclear atypia from minimum (grade 1, cytologic atypia falls short of ECCC cells) to maximum (grade 3, cytologically identical to ECCC cells), argues in favor of our hypothesis that these may represent precursor lesions of ECCC. Further studies are required to conclusively define the nature of these lesions. However, such studies can only be performed if diagnostic surgical pathologists recognize, highlight, and segregate these lesions for further analysis.

My approach to the interpretation of endometrial biopsies and curettings

A major proportion of the workload in many histopathology laboratories is accounted for by endometrial biopsies, either curettage specimens or outpatient biopsy specimens. The increasing use of pipelle and other methods of biopsy not necessitating general anaesthesia has resulted in greater numbers of specimens with scant tissue, resulting in problems in assessing adequacy and in interpreting artefactual changes, some of which appear more common with outpatient biopsies. In this review, the criteria for adequacy and common artefacts in endometrial biopsies, as well as the interpretation of endometrial biopsies in general, are discussed, concentrating on areas that cause problems for pathologists. An adequate clinical history, including knowledge of the age, menstrual history and menopausal status, and information on the use of exogenous hormones and tamoxifen, is necessary for the pathologist to critically evaluate endometrial biopsies. Topics such as endometritis, endometrial polyps, changes that are induced by hormones and tamoxifen within the endometrium, endometrial metaplasias and hyperplasias, atypical polypoid adenomyoma, adenofibroma, adenosarcoma, histological types of endometrial carcinoma and grading of endometrial carcinomas are discussed with regard to endometrial biopsy specimens rather than hysterectomy specimens. The value of ancillary techniques, especially immunohistochemistry, is discussed where appropriate.

Immunohistochemical and functional biomarkers of value in female genital tract lesions

There has been a marked expansion in the literature pertaining to the use of immunohistochemical markers in female genital tract pathology, especially with regard to diagnosis. This review provides a survey of the antibodies commonly used in the diagnosis of gynecological lesions grouped as to function or type. Prognostic or predictive markers are also discussed where appropriate, although few of these are of value in everyday practice. It is stressed that when immunohistochemistry is used diagnostically, panels of markers provide better information than reliance on a single antibody.

Immunohistochemical staining for Ki-67 and p53 helps distinguish endometrial Arias-Stella reaction from high-grade carcinoma, including clear cell carcinoma

The distinction of the Arias-Stella reaction from clear cell carcinoma of the endometrium is usually straightforward; however, this differential diagnosis can be difficult when the Arias-Stella reaction occurs outside the setting of pregnancy or in older patients. The differential diagnosis also is problematic when serous or clear cell carcinoma focally arises within an endometrial polyp, as part of "endometrial intra-epithelial carcinoma" (EIC), or in younger patients. The goal of this study was to determine whether immunohistochemical staining can distinguish the Arias-Stella reaction from endometrial high-grade carcinoma, particularly clear cell carcinoma. Cases of endometrial Arias-Stella reaction (n = 27), clear cell carcinoma (n = 11), serous carcinoma (n = 7), and EIC (n = 4) were assessed by immunohistochemical staining with antibodies for Ki-67, p53, estrogen receptor (ER), and progesterone receptor (PR). Composite immunohistochemical scores based on the percentage and intensity of stained cells were calculated, as was the overall positivity (percentage positive cases), using a cutoff value of >/=5% stained cells and at least weak intensity. Appropriate statistical tests were performed. Ki-67 and p53 immunostaining was significantly less in Arias-Stella reaction than in clear cell carcinoma (p < 0.0001 for both) or serous carcinoma/EIC (p < 0.0001 for both), measured by the composite immunohistochemical scores or overall positivity. ER showed a significant difference only between Arias-Stella reaction and clear cell carcinoma; PR showed a significant difference only between Arias-Stella reaction and serous carcinoma/EIC. When clinical or histologic features cannot facilitate the differential diagnosis, immunohistochemical staining for Ki-67 and p53 may help distinguish endometrial Arias-Stella reaction from clear cell carcinoma and other types of high-grade carcinoma.

Ki-67, Bcl-2 and p53 expression in endometrial polyps and in the normal endometrium during the menstrual cycle

OBJECTIVE

To determine the presence of proteins related to proliferation (Ki-67) and apoptosis (Bcl-2, p53) in endometrial polyps and normal endometrium during the menstrual cycle.

DESIGN

Retrospective study using paraffin embedded tissue.

SETTING

Hospital affiliated to the university.

POPULATION

Premenopausal patients with endometrial polyps.

METHODS

Seventy-eight premenopausal patients in different phases of the menstrual cycle were submitted to polypectomy using the Bettocchi hysteroscope. Immunohistochemistry was used to detect the expression of these proteins in endometrial polyps. One hundred and eighteen normal endometrial biopsies were used as controls.

MAIN OUTCOME MEASURES

Detection of Bcl-2 and Ki-67 expression by immunohistochemistry.

RESULTS

In endometrial polyps, Ki-67, p53 and Bcl-2 expression was detected with more frequency during the proliferative than during the luteal phase of the cycle. Similar findings were observed in the normal endometrium.

CONCLUSION

Endometrial polyps undergo cyclic changes in the expression of their proteins related to proliferation and apoptosis during the menstrual cycle, similar to those of the cycling endometrium.

A critical appraisal of the value of immunohistochemistry in diagnosis of uterine neoplasms

In recent years there have been a plethora of publications regarding the value of immunohistochemical studies in diagnosis in gynecological pathology. In many instances, papers are published initially that suggest that a certain antibody or panel of antibodies is of value in the diagnosis of a particular neoplasm and in the distinction of this from mimics. However, this is usually quickly followed by other studies that somewhat contradict these findings. The aim of this review is to present a critical appraisal of the value of immunohistochemical studies in the diagnosis of uterine neoplasms with emphasis on the recent literature. It is stressed that immunohistochemistry is necessary in relatively few cases and a knowledge of the potential immunoreactivity of utilized antibodies is required. With regard to endometrial carcinoma, topics discussed in this review include antibodies of value in the distinction between type 1 and type 2 carcinoma, in the characterization of focal serous proliferations in endometrial polyps and non-polypoid endometrium, in the sometimes problematic distinction between an endometrial and an endocervical adenocarcinoma, and in the distinction between a uterine and ovarian serous carcinoma. The value of CD10 as a proposed marker of mesonephric adenocarcinoma is also discussed. With regard to uterine mesenchymal neoplasms, a critical appraisal of the value of relatively new antibodies, including CD10 and h-caldesmon, in distinguishing between a smooth muscle and an endometrial stromal neoplasm is discussed as is the immunophenotype of two rare uterine mesenchymal neoplasms, uterine tumor resembling ovarian sex cord tumor (UTROSCT) and perivascular epithelioid cell tumor (PEComa).

Immunohistochemistry in gynecological pathology

Although the majority of diagnoses in gynecological pathology are established on examination of routine hematoxylin and eosin stained sections, additional tests are occasionally required. Immunohistochemistry is widely used to provide additional diagnostic information in problematic cases. This review touches on some of the basics of the procedure, presents an example immunohistochemical panel, and discusses some of the most common immunohistochemical markers used in diagnostic gynecological pathology. Differential diagnostic problems and relevant immunohistochemical stains for the vulva, vagina, cervix, uterus, and ovary are also addressed.

P53 expression in spontaneous and estradiol-induced endometrial hyperplasia during menopause

OBJECTIVE

To determine the percentage of endometrial hyperplasia positive for p53 expression in both spontaneously occurring cases or following the use of unopposed estradiol.

METHODS

Fifty-four postmenopausal patients with endometrial hyperplasia diagnosed by endometrial biopsy and hysteroscopy were recruited to this study. Thirty-three patients had used unopposed estradiol for periods of time from 1 to 3 years. P53 expression was detected in paraffin-embedded endometrial specimens by immunohistochemical methods.

RESULTS

The percentage of endometrial hyperplasia positive for p53 expression was significantly greater in spontaneously occurring hyperplasia than in cases induced by the unopposed use of estradiol.

CONCLUSION

Endometrial hyperplasia caused by the unopposed use of estradiol during menopause probably harbors fewer genomic errors than those cases occurring spontaneously.

Bcl-2, iNOS, p53 and PCNA expression in normal, disordered proliferative, hyperplastic and malignant endometrium

We attempted to determine Bcl-2, inducible nitric oxide synthase (iNOS), p53 and proliferating cell nuclear antigen (PCNA) expression, and the relationships between them, in endometrioid adenocarcinomas and precursor lesions. Expression of Bcl-2, iNOS, p53 and PCNA were investigated immunohistochemically in 91 samples from benign (proliferative (pEM), secretory (sEM), disordered proliferative (dEM), inactive/atrophic (aEM), hyperplastic endometrium) and malignant endometrial tissue. Staining scores for Bcl-2 in the dEM, endometrial hyperplasia (EMH) and endometrioid cancer (ECA) groups were higher than in the pEM group (P = 0.004; P = 0.036 and P = 0.020, respectively). A significant difference in proliferating cell nuclear antigen staining was found between simple and complex EMH samples (P = 0.000). An inverse relationship was found between iNOS and p53 in the hyperplasia group (r = -0.533, P = 0.019). While a significant difference was found in p53 staining in ECA between the pEM, dEM and EMH groups, no such difference was found in iNOS staining. In addition, there was no direct relationship between iNOS and p53 in the ECA group. It was concluded that the interaction between iNOS, p53 and Bcl-2 in proliferative processes in the development of type 1 endometrioid adenocarcinomas is different from that in tumors originating in other organs.

Expression of cyclin D1 in normal, metaplastic, hyperplastic endometrium and endometrioid carcinoma suggests a role in endometrial carcinogenesis

CONTEXT

Endometrioid carcinoma is often preceded by characteristic histopathologic lesions known as endometrial hyperplasia. Estrogen appears to be involved in the development of endometrioid carcinoma. Other mechanisms of endometrial carcinogenesis include mutations in p53 and PTEN tumor suppressor genes and overexpression of cyclin D1. However, the pattern of cyclin D1 expression is not well defined in normal, hyperplastic, neoplastic, and metaplastic endometrium.

DESIGN

Cyclin D1 immunohistochemical analysis was used to evaluate 108 fixed, paraffin-embedded endometrial biopsy specimens and uterine resections obtained from 108 patients. Specimens included proliferative and secretory endometria, simple and complex hyperplastic lesions, and endometrioid adenocarcinoma. Normal and metaplastic surface epithelia were also evaluated independently of glandular morphologic features.

RESULTS

Cyclin D1 was significantly overexpressed in glands with complex hyperplasia and endometrioid adenocarcinoma compared with proliferative or secretory endometrium and simple hyperplasia. Significant overexpression was also noted in papillary, syncytial, and squamous metaplasias compared with normal surface epithelium or epithelium with tubal metaplasia.

CONCLUSION

Overexpression of cyclin D1 increases from normal endometrium to hyperplasia and carcinoma, suggesting that it may play a role in endometrial carcinogenesis. Overexpression of cyclin D1 in endometrial glands was independent from overexpression of cyclin D1 in surface metaplastic epithelium.