Endometrial Glandular Dysplasia Research Articles

SIX1 Regulates Aberrant Endometrial Epithelial Cell Differentiation and Cancer Latency Following Developmental Estrogenic Chemical Exposure.

Early-life exposure to estrogenic chemicals can increase cancer risk, likely by disrupting normal patterns of cellular differentiation. Female mice exposed neonatally to the synthetic estrogen diethylstilbestrol (DES) develop metaplastic and neoplastic uterine changes as adults. Abnormal endometrial glands express the oncofetal protein sine oculis homeobox 1 (SIX1) and contain cells with basal [cytokeratin (CK)14+/18-] and poorly differentiated features (CK14+/18+), strongly associating SIX1 with aberrant differentiation and cancer. Here, we tested whether SIX1 expression is necessary for abnormal endometrial differentiation and DES-induced carcinogenesis by using Pgr-cre to generate conditional knockout mice lacking uterine Six1 (Six1 d/d). Interestingly, corn oil (CO) vehicle-treated Six1 d/d mice develop focal endometrial glandular dysplasia and features of carcinoma in situ as compared with CO wild-type Six1 (Six1 +/+) mice. Furthermore, Six1 d/d mice neonatally exposed to DES had a 42% higher incidence of endometrial cancer relative to DES Six1 +/+ mice. Although DES Six1 d/d mice had >10-fold fewer CK14+/18- basal cells within the uterine horns as compared with DES Six1 +/+ mice, the appearance of CK14+/18+ cells remained a feature of neoplastic lesions. These findings suggest that SIX1 is required for normal endometrial epithelial differentiation, CK14+/18+ cells act as a cancer progenitor population, and SIX1 delays DES-induced endometrial carcinogenesis by promoting basal differentiation of CK14+/18+ cells. In human endometrial biopsies, 35% of malignancies showed CK14+/18+ expression, which positively correlated with tumor stage and grade and was not present in normal endometrium. IMPLICATIONS: Aberrant epithelial differentiation is a key feature in both the DES mouse model of endometrial cancer and human endometrial cancer. The association of CK14+/18+ cells with human endometrial cancer provides a novel cancer biomarker and could lead to new therapeutic strategies.

Serous carcinoma arising from uterine adenomyosis/adenomyotic cyst of the cervical stump: a report of 3 cases

BackgroundSerous carcinoma arising in adenomyosis and adenomyotic cyst is very rare. Only 3 serous carcinomas and 5 serous endometrial intraepithelial carcinomas (EIC) have been reported to date.MethodsWe reviewed the clinicopathological features of 2 serous carcinoma in uterine adenomyosis and 1 serous EIC in adenomyotic cyst of the cervical stump.ResultsCase 1 had an endometrial serous carcinoma in the uterine myometrium and the left ovary. A minor component of benign endometrial glands with minimal endometrial stroma was found in the uterine mass and the surrounding myometrium. Case 2 showed 3 small foci of serous carcinoma, serous EIC and endometrial glandular dysplasia (EmGD) in the adenomyosis. Scanty serous carcinoma was present in the endometrium without evidence of myometrial invasion. The eutopic endometrium in both case 1 and 2 had no evidence of neoplastic changes after complete examination. Case 3 had 3 microscopic serous EICs in the adenomyotic cysts of the cervical stump. One EIC lesion coexisted with EmGD. No cancer was found in the endocervical tube although the preoperative endocervical biopsy showed a poorly differentiated endometrioid carcinoma. Immunohistochemistry demonstrated that serous carcinoma in case 1 and EIC in all 3 cases showed a characteristic pattern of p53 and p16 over expression, high Ki67 index, and lack of WT1, ER and PR staining. EmGD in case 1 and 3 had a similar staining pattern except a lower Ki67 index and the presence of ER expression.ConclusionsWe believe that this case series may expand our recognition on serous carcinoma arising in uterine adenomyosis/adenomyotic cyst including extra-uterine spread and the potential synchronous growth of carcinomas in eutopic endometrium.

Serous Endometrial Intraepithelial Carcinoma Arising in Adenomyosis

Serous endometrial intraepithelial carcinoma (serous EIC) arising in adenomyosis is rare. It may be underrecognized because of its deceiving morphology when embedded in the foci of adenomyosis. Although there is no connection to peritoneal cavity, some cases may be associated with extrauterine disease. It is currently unknown what the etiology for such a disease is. More studies are in need to elucidate the pathogenesis of such a grave malady. We report a series of 5 cases of serous EIC, which may arise in adenomyosis. The 5 cases are in 5 different patients or whom on histopathological examination of their hysterectomy specimens, the finding of adenomyosis involved with serous intraepithelial neoplasia was identified. The finding of interest was the presence of multifoci of adenomyosis; some of those foci were involved in serous EIC. In addition to EIC, lesions of endometrial glandular dysplasia were present in the foci of adenomyosis. To rule out the possibility of endometrial serous carcinoma (ESC) invading into the areas of the adenomyosis, all of the 5 uteri were extensively examined. Among the 5 uteri, the eutopic endometirum showed 1 invasive ESC, 2 serous EIC, and 2 benign resting endometrium without any cancer or precancerous lesions. In 1 uterus with ESC, we did not see any direct spatial connection between the invasive component of ESC and the areas of EIC in the foci of adenomyosis. In 2 uteri with serous EIC within the endometrial cavity, there was a distance of at least 0.5 cm between the lesions within the endometrial cavity and the serous EIC in adenomyosis. The remaining 2 uteri showed no evidence of endometrial malignancy in the endometrial cavity, whereas serous EIC was present only in areas of adenomyosis. Clinicopathologic data including characterized immunohistochemical stainings and p53 gene sequence analysis are presented and clinical significance is discussed.

A Proposed Model for Endometrial Serous Carcinogenesis

Endometrial serous carcinomas constitute no more than 10% of endometrial adenocarcinomas, but frequently present at an advanced stage and have a significantly worse prognosis than the more common low-grade and intermediate-grade endometrioid adenocarcinomas. The neoplasm's potential for rapid tumor progression and the high mortality that is associated with advanced-stage disease underscore the importance of understanding endometrial serous carcinogenesis so that its precancers can be diagnosed and an effective therapeutic intervention can be administered. In this study, the authors summarize the current state of knowledge on endometrial serous carcinogenesis and propose a model for its development based on recent work from our group and published data from other researchers. In this model, endometrial serous carcinoma arises predominantly in the resting endometrium, manifesting first as p53 immunoreactive, morphologically normal endometrial cells (p53 signatures), evolving to endometrial glandular dysplasia (which is the first morphologically identifiable precursor lesion), then to serous endometrial intraepithelial carcinoma (a carcinoma with a noninvasive growth pattern in the uterus but which is not infrequently associated with extrauterine disease), and finally into fully developed serous carcinoma. Endometrial glandular dysplasia is a lesion, which can be diagnosed by routine microscopic evaluation, whose ablation or removal may potentially offer the opportunity to prevent the development of the associated malignancy. The diagnostic criteria, practical applicability, and evidentiary basis for the delineation of this lesion are studied.

Evidence for a latent precursor (p53 signature) that may precede serous endometrial intraepithelial carcinoma

Both serous intraepithelial carcinoma and endometrial glandular dysplasia are associated with uterine serous carcinoma. Recently a candidate serous cancer precursor containing p53 mutations (p53 signature) was described in the fallopian tube. We analyzed normal and neoplastic endometrium for a similar entity. In total 10 endometrial polyps involved by intraepithelial and/or invasive carcinoma and 137 benign polyps were studied. All were stained for p53 and MIB-1. A subset of p53 signatures and carcinomas were analyzed for γ-H2AX and p53 mutations. p53 signatures were identified in 7 of 10 cases intraepithelial carcinoma and were multicentric in 2. In one case, the signature was in continuity with intraepithelial carcinoma. Of 137 benign polyps (4%), 6 contained p53 signatures. The MIB-1 fraction in most signatures was less than 5%, and ranged from 50 to 90% in carcinomas. DNA damage (γ-H2AX) was demonstrated in both p53 signatures and adjacent carcinomas but not in benign polyps. Shared identical p53 mutations were found in paired signatures and carcinomas in two of three cases analyzed, including one case with multiple signatures. In one, a coexistent invasive serous cancer was not found to contain a p53 mutation. In a third, a p53 signature and an invasive cancer harbored two different p53 mutations. This is the first description of p53 signatures adjacent to carcinoma, suggesting a role for this entity in the genesis of serous malignancy. The significance of p53 signatures in benign conditions (polyps) remains to be determined. The role of the p53 signature in early serous neoplasia is discussed.

Endometrial Glandular Dysplasia with Frequent p53 Gene Mutation: A Genetic Evidence Supporting Its Precancer Nature for Endometrial Serous Carcinoma

Endometrial glandular dysplasia (EmGD) has been recently proposed to be a putative precursor to endometrial serous carcinoma (ESC). The purpose of this study is to determine if EmGD is genetically linked to ESC and if it can be used for early detection. The tumor suppressor p53 gene was sequenced from serial samples of benign and neoplastic endometria with serous differentiation. The study group contained 15 neoplastic uteri and the control group had 12 age-matched benign uteri. A total of 139 informative samples were obtained, including 55 resting endometrium, 37 EmGD, 25 serous endometrial intraepithelial carcinoma (EIC), and 22 ESC. At least one representative section from each uterus was used for p53 immunohistochemical staining to correlate p53 overexpression with gene mutation status. The mutations of p53 were detected in 0%, 43%, 72%, and 96% in resting endometrium, EmGD, serous EIC, and ESC, respectively. More than 50% of the neoplastic uteri showed at least one identical p53 gene mutant among lesions of EmGD, serous EIC, and/or ESC. The majority of lesions showed overexpression of p53 protein, which was significantly correlated with p53 gene mutation (P < 0.01). This genetic evidence strongly supports that EmGD represents the precancer of ESC or serous EIC. Mutation of p53 gene is probably one of the most important factors to initiate the endometrial serous carcinogenesis. Correct identification of EmGD will provide us an opportunity of early diagnosis and a potentially effective therapeutic modality to control ESC.

Endometrial glandular dysplasia and endometrial intraepithelial neoplasia

In recent decades, progress has been made in defining endometrial precancers. Endometrial intraepithelial neoplasia has been widely accepted as a precancer of type I endometrial cancer, while endometrial glandular dysplasia is a newly described entity as a probable precancer of type II cancer. As endometrial intraepithelial neoplasia has been discussed more extensively in the literature, we focus more on the recent development of endometrial glandular dysplasia in this review. Serous endometrial intraepithelial carcinoma was previously considered as a putative precancer for endometrial serous carcinoma or uterine papillary serous carcinoma. It is now considered as an early form of endometrial serous carcinoma, however. Endometrial glandular dysplasia was found to be a better candidate for precancer for both endometrial serous and clear cell carcinomas, which meets almost all recently defined criteria for precancer. Biomarkers of p53 and IMP3 are helpful for the early detection of endometrial glandular dysplasia as well as type II endometrial cancers. Two types of endometrial cancers are derived from two different precancers. Type I endometrioid carcinoma develops from endometrial intraepithelial neoplasia, while type II derives most probably from endometrial glandular dysplasia. Recognition and correct detection of endometrial glandular dysplasia may deepen our understanding and improve prevention and clinical management for type II endometrial cancer.

The Oncofetal Protein IMP3

Insulin-like growth factor II mRNA-binding protein 3 (IMP3) is an oncofetal protein highly expressed in fetal tissue and malignant tumors but rarely found in adult benign tissues. The aim of this study is to determine the expression of IMP3 in benign endometrium, endometrial cancer, and its precursor lesions, trying to see whether IMP3 has any diagnostic usage. Two hundred ninety-eight endometrial samples were examined for IMP3 expression by immunohistochemistry. These included benign endometrium (n=68), atypical hyperplasia or endometrial intraepithelial neoplasia (n=35), endometrial glandular dysplasia (n=21), endometrial intraepithelial carcinoma (n=18), endometrioid carcinoma (n=70), mucinous carcinoma (n=8), serous carcinoma (n=51), clear cell carcinoma (n=12), and other malignancies (n=15). Maturational patterns in the 68 benign endometrial samples included atrophic (n=12), proliferative (n=18), secretory (n=14), menstrual (n=8), and gestational (n=16). Most of the carcinomas were histologically pure; where mixed, the second component constituted <10% of the total tumor volume. The extent and intensity of IMP3 expression was semiquantitatively determined and scored for all samples. A renal cell carcinoma with known IMP3 expression was used as positive control for each immunohistochemistry run. Among the malignant cases, IMP3 expression was predominantly found in endometrial serous carcinoma and its putative precursor lesions, with 3 (14%) of 21 endometrial glandular dysplasia, 16 (89%) of 18 serous endometrial intraepithelial carcinoma, and 48 (94%) of 51 serous carcinomas (P<0.001). In contrast, the frequency of IMP3 expression was significantly lesser in nonserous malignancies with 0 (0%) of 35, 5 (7%) of 70, 0 (0%) of 8, 3 (25%) of 12, and 5 (33%) of 15 positive expression rates in atypical hyperplasia or endometrial intraepithelial neoplasia, endometrioid, mucinous, clear cell carcinomas, and other malignancies, respectively. The IMP3 staining was universally cytoplasmic, with diffuse staining of strong intensity in serous carcinomas, whereas staining was typically patchy and of moderate or weak intensity in nonserous malignancies. Among the benign endometrial samples, decidualized endometrial stroma showed 100% positivity for IMP3. The remaining samples were negative, with the exception of a few weakly proliferative glands in 3 (5%) of 68 cases that showed focal weak immunoreactivity of IMP3. The trophoblasts in the first trimester chorionic villi were also diffusely positive, which was consistent with previously reported findings. We conclude that expression of IMP3, a newly identified cytoplasmic marker, is closely associated with type II endometrial cancer. It seems that IMP3 expression is associated with an aggressive histologic phenotype among endometrial neoplastic lesions. Strong and diffuse IMP3 expression is highly sensitive for endometrial serous and clear cell carcinomas including their putative precursor lesions. Therefore, IMP3 may be a useful diagnostic marker in the assessment of endometrial cancers and their precursor lesions, particularly when the amount of available tissue material is limited and a concern of type II cancer arises. High frequency of IMP3 expression is present in decidualized endometrial stroma of gestational endometrium and chorionic villi in early pregnancy. Although the significance of the latter finding remains unclear, the differential diagnosis between decidual changes and endometrial serous carcinoma is rarely problematic.

Endometrial Glandular Dysplasia (EmGD): morphologically and biologically distinctive putative precursor lesions of Type II endometrial cancers.

In this article, the authors briefly review the historical evolution of the various putative precursor lesions for Type II endometrial cancers, with an emphasis on the newly defined "Endometrial Glandular Dysplasia (EmGD)". The evidentiary basis for delineating serous EmGD as the most probable precursor lesions to endometrial serous carcinoma is reviewed in detail. An argument is advanced for the discontinuation of the term serous "endometrial intraepithelial carcinoma (EIC)" as a descriptor for a supposedly intraepithelial, precancerous lesion. Preliminary evidence is also presented that suggests that there is a morphologically recognizable "clear cell EmGD" that probably represents a precancerous lesion to endometrial clear cell carcinomas.

Occurrence of Endometrial Glandular Dysplasia Precedes Uterine Papillary Serous Carcinoma

Endometrial glandular dysplasia (EmGD) is a newly defined entity that is commonly and specifically associated with serous endometrial intraepithelial carcinoma and uterine papillary serous carcinoma (UPSC). Endometrial glandular dysplasia has been proposed as a true precancerous lesion of UPSC based on our recent studies showing morphological and molecular linkages between these 2 lesions. The present report is to examine if EmGD occurs before UPSC development and to define the period from the occurrence of EmGD to a full-blown UPSC by studying their clinicopathologic features in a retrospective setting. A total of 250 UPSC and 258 benign cases were used as initial study source. To identify if EmGD existed before the development of UPSC, we blindly reviewed all available endometrial biopsies from a period of 3 months or earlier before hysterectomies. These included an available pool of 27 biopsy specimens from UPSC group and 29 samples from benign control group. Any endometrial abnormalities, which morphologically qualified as EmGD as defined previously in preceding biopsies were recorded. Among all endometrial biopsies before hysterectomies, we morphologically identified a total of 10 EmGD cases; 9 (33%) of 27 were from UPSC group and 1 (3.5%) of 29 were from benign control group. All 10 morphologically diagnosed EmGD cases showed a high p53 staining score (>/=5) except 1 noncontributory from UPSC group and 1 from the benign control group with a score of 0. A high MIB-1 index score was seen in all EmGD cases, whereas low index was found in morphologically benign biopsies. The main purpose of this study is to report these retrospectively identified EmGD cases. The period from identifying EmGD to the presence of either a serous endometrial intraepithelial carcinoma or a full-blown UPSC ranged from 16 to 98 months with an average of 33 months. We conclude that occurrence of EmGD precedes the development of UPSC. The findings support our recently proposed UPSC development model, in which EmGD is likely to be a precursor lesion of UPSC. Further studies are needed to address issues in regard to molecular and cellular mechanisms, reversibility, risk of UPSC development, and clinical management of EmGD.

Endometrial Glandular Dysplasia: A Putative Precursor Lesion of Uterine Papillary Serous Carcinoma. Part II: Molecular Features

Endometrial glandular dysplasia (EmGD) may be a newly defined precursor lesion of uterine papillary serous carcinoma (UPSC) by morphology. In this report, we studied molecular changes present in EmGD by the loss of heterozygosity (LOH) approach using laser capture microdissected tissue samples. Nineteen uteri showing at least 1 focus of EmGD by morphology were selected. These cases were 12 UPSC, 2 clear cell carcinomas, 1 mixed uterine papillary serous and endometrioid carcinoma, 1 uterine carcinosarcoma, 1 serous endometrial intraepithelial carcinoma (EIC), and 2 EmGD involving endometrial polyps. Seven microsatellite polymorphic DNA markers (TP53 at 17p, D1S211, and D1S162 at 1p32, D17S1323 at 17q21, D17S1330 at 17q25, D5S346 at 5q, and D2S123 at 2p) were utilized. A total of 123 laser-captured microdissection samples from 19 cases was studied with LOH method. The frequencies and patterns of LOH were analyzed and compared among benign resting endometrium (RE), EmGD, serous EIC, and UPSC. LOH was observed for at least 1 of the 7 markers in all categories of lesions, EmGD, serous EIC, and UPSC. The frequency of LOH for EmGD ranged from 4.2% to 31.3%; the range for serous EIC was 5.9% to 78.6%; and that for UPSC was 7.7% to 62.5%. The most frequent LOH in the 3 above-cited categories of lesions was identified at 17p (TP53) and 1p (D1S162). The frequency of LOH in EmGD with markers of TP53 and D1S162 was significantly higher than in RE (p < 0.05). With markers of D1S211 and D2S123, LOH in EmGD was higher than RE, approaching to a statistically significant level. Compared with foci of serous EIC and UPSC, however, the rate of LOH in EmGD was significantly lower only with TP53 locus (31.3% vs more than 60%, p < 0.05). The difference of LOH frequency with other chromosomal markers between EmGD and serous EIC/UPSC did not reach a statistically significant level. A significantly high concordant LOH pattern was found between foci of EmGD and serous EIC/UPSC (p = 0.05). We conclude that EmGD frequently shows LOH at multiple chromosomal loci, particularly at 17p and 1p. Significantly high concordant LOH frequency between EmGD and paired serous EIC or UPSC strongly suggests that EmGD is a noncancerous precursor lesion of UPSC, probably also of serous EIC. The clinical significance of EmGD needs further studies.