Wenxin Zheng

The oncofetal protein IMP3: A novel biomarker for endometrial serous carcinoma

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.

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.

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.

Regulation of non-AU-rich element containing c-fms proto-oncogene expression by HuR in breast cancer

The role of RNA-binding proteins in cancer biology is recognized increasingly. The nucleocytoplasmic shuttling and AU-rich RNA-binding protein HuR stabilizes several cancer-related target mRNAs. The proto-oncogene c-fms, whose 3′untranslated region (3′UTR) is not AU-rich, is associated with poor prognosis in breast cancer. Using a large breast-cancer tissue array (N=670), we found nuclear HuR expression to be associated with nodal metastasis and independently with poor survival (P=0.03, RR 1.45), as well as to be co-expressed with c-fms in the breast tumors (P=0.0007). We described c-fms mRNA as a direct target of HuR in vivo, and that HuR bound specifically to a 69-nt region containing ‘CUU’ motifs in 3′UTR c-fms RNA. Overexpressing or silencing HuR significantly up- or down-regulated c-fms RNA expression, respectively. We also found that known glucocorticoid stimulation of c-fms RNA and protein is largely dependent on the presence of HuR. HuR, by binding to the 69-nt wild type, but not mutant, c-fms sequence can regulate reporter gene expression post-transcriptionally. We are the first to describe that HuR can regulate gene expression by binding non-AU-rich sequences in 3′UTR c-fms RNA. Collectively, our findings suggest that HuR plays a supportive role for c-fms in breast cancer progression by binding a 69-nt element in its 3′UTR, thus regulating its expression.

Correlation of tumor phenotype with c-fms proto-oncogene expression in an in vivo intraperitoneal model for experimental human breast cancer metastasis

Although proto-oncogene expression has been shown to correlate with clinical outcome in breast carcinoma, an experimental model has not been proposed to study this phenomenon in vivo. In addition, the ability to modulate this proto-oncogene in vivo to correlate with phenotypic behavior has not been determined. Utilizing an intraperitoneal model for metastatic spread with BT20 human breast carcinoma cells, clonally expanded cells expressing five fold higher c-fms protein were compared with parent BT20 cells as well as an underexpressing clone using intrasplenic injection following left flank cut-down in female nude and Severe combined immunodeficient (SCID) mice. Athymic BALB/c nude and SCID animals were observed for clinical evidence of tumorigenicity with necropsy performed at either 50 or 80 days unless compromised earlier. Immunohistochemistry (IHC) of the harvested tumors was performed to correlate c-fms expression from its original in vitro culture to the in vivo model. At day 50, differences in primary tumor take and spread to the pelvis were already evident favoring the c-fms over-expression group with IHC of these tumors revealing significantly higher intensity of staining for c-fms, (mean H score of 205 vs. 43 in the over-expression and parent groups, respectively). At day 80, tumor take and spread was comparable; however, tumor size in the over-expression group was significantly larger than the parent and under-expressing group in both the BALB/c and SCID experiments. Modulation of c-fms proto-oncogene expression was also achieved using the anti-glucocorticoid, RU-486, via oral administration to SCID mice with subsequent correlation to IHC staining. This model thus provides tumors of significant size and organ diversity which retain their phenotype early in tumorigenesis allowing an early endpoint to assess efficacy of novel treatments.

Serous endometrial intraepithelial carcinoma arising in adenomyosis: a report of 5 cases.

Serous endometrial intraepithelial carcinoma (serous EIC) arising in adenomysis is rare. It may be underrecognized because of its deceiving morphology when embedded in the foci of adenomysis. 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.

Sertoliform endometrioid carcinoma of the endometrium with dual immunophenotypes for epithelial membrane antigen and inhibin α: Case report and literature review

Summary We report a rare case of sertoliform endometrioid carcinoma of the endometrium in a 71-year-old African American woman who presented with postmenopausal bleeding. Her medical condition was remarkable for hypertension, diabetes, and obesity. She underwent total hysterectomy, right salpingo-oophorectomy and lymph node sampling. The endometrium was occupied by a 4.5-cm solid polypoid tumor, which grossly invaded into the myometrium. Microscopically, the tumor consisted of small hollow tubules, anastomosing cords and trabeculae, and tightly packed nests. Microglandular areas mimicking adult granulosa cell tumors were also present. But true Call-Exner bodies were absent. Component of typical endometrioid carcinoma was noted only focally. The uninvolved endometrium demonstrated atypical complex hyperplasia. The tumor cells were diffusely immunoreactive for epithelial membrane antigen, estrogen receptor, and progesterone receptor (PR), and focally for vimentin. The tumor cells were also diffusely positive for inhibin &agr; and CD99. Immunostains for other sex cord markers (calretinin, WT-1, and Melan-A) were also positive in approximately 30% to 40% of the tumor cells. Immunostains for CD10, smooth muscle actin, desmin, or HHF35 were negative. Two ovarian sertoliform endometrioid carcinomas from our archived tissue were, however, immunoreactive for epithelial membrane antigen but negative for inhibin &agr;. Despite the prominent sertoliform features, both histologically and immunohistochemically, the tumor was of a high-grade endometrial carcinoma and will likely behave as such. As of today, dual differentiation of epithelium and sex cord by immunohistochemical staining has not been demonstrated in sertoliform endometrioid carcinomas of either endometrial or ovarian origin. Our case is the first documentation of such example and suggests that endometrial carcinoma can undergo true sex cord differentiation.

Pilot Clinical Evaluation of a Confocal Microlaparoscope for Ovarian Cancer Detection.

Objective The aim of this study is to evaluate the performance of a confocal fluorescence microlaparoscope for in vivo detection of ovarian cancer. Methods/Materials Seventy-one patients scheduled for open or laparoscopic oophorectomy were consented for the imaging study. High-resolution confocal microlaparoscopic images of the epithelial surface of the ovary were acquired in vivo or ex vivo after tissue staining using acridine orange. Standard histologic evaluation of extracted tissue samples was performed and used as the gold standard of disease diagnosis. Trained human observers from different specialties viewed the microlaparoscopic images, rating each image on a 6-point scale ranging from “definitely not cancer” to “definitely cancer.” Receiver operating characteristic curves were generated using these scores and the gold standard histopathologic diagnosis. Area under the receiver operating characteristic curve (AUC) was calculated as a performance metric. Results Forty-five of the consented patients were used in the final evaluation study. From these 45 patients, 63 tissue locations or samples were identified and imaged with the confocal microlaparoscope. Twenty of the samples were high-grade cancers, and the remaining 43 samples were normal or noncancerous. Twenty-three of the samples were imaged in vivo, and the remaining 40 samples were imaged ex vivo. The average AUC score and standard error (SE) for detection of cancer in all images were 0.88 and 0.02, respectively. An independent-samples t test was conducted to compare AUC scores for in vivo and ex vivo conditions. No statistically significant difference in the AUC score for in vivo (AUC, 0.850; SE, 0.049) and ex vivo (AUC, 0.888; SE, 0.027) conditions was observed, t(6) = 1.318, P = 0.2355. Conclusions Area under the receiver operating characteristic curve scores indicate that high-resolution in vivo images obtained by the confocal laparoscope can distinguish between normal and malignant ovarian surface epithelium. In addition, in vivo performance is similar to that which can be obtained from ex vivo tissue.

Malignant Female Adnexal Tumor of Probable Wolffian Origin: Case Report and Literature Review

Although most female adnexal tumors of probable Wolffian origin have a benign biologic behavior, occasional cases have exhibited malignant potential. We encountered a 50-yr-old woman with an uncommon female adnexal tumors of probable Wolffian origin, which involved bilateral ovaries, invaded the ipsilateral fallopian tube, and extended to the uterine serosa. The initial histopathologic presentation caused significant confusion in pathologic diagnosis. Multiple differential diagnoses including ovarian endometrioid carcinoma, Sertoli cell tumor, and metastasis from nongynecologic organs were considered. After careful examination of the histologic findings and a thorough investigation with multiple immunohistochemical stains, the diagnosis was ultimately established. A literature review on female adnexal tumors of probable Wolffian origin including a malignant form is presented.

Assessment of the Role of Intraoperative Frozen Section in Guiding Surgical Staging for Endometrial Cancer.

Objective The aim of this study was to assess the role of intraoperative frozen section (FS) in guiding decision making for surgical staging of endometrioid endometrial cancer (EC). Methods Medical records were collected retrospectively on 112 patients with endometrioid EC, who underwent total hysterectomy and bilateral salpingo-oophorectomy at the University of Arizona Medical Center from January 1, 2010, to December 31, 2014. Only patients with endometrioid adenocarcinoma, grade 1, less than 50% myometrial invasion, and tumor size less than 2 cm determined by intraoperative FS omitted lymphadenectomy; otherwise, surgical staging was performed with lymph node dissection. The FS results were compared with the permanent paraffin sections (PSs) to assess the diagnostic accuracy. Results The concordance rate of different variables between FS and PS in EC was 100%, 89.3% (100/112), 97.3% (109/112), and 95.5% (107/112), respectively, with respecting to histological subtype, grade, myometrial invasion, and tumor size. Diagnostic accurate rate of combined risk factors deciding surgical staging at the time of FS was 95.5% (107/112), and the discordance rate of all risk factors considered between FS and PS was 4.5%, resulting 3 cases (2.7%) undertreated and 2 cases (1.8%) overtreated. Conclusions Despite nonideal FS evaluation, intraoperative FS diagnosis for EC is highly reliable by providing guidance for the intraoperative decisions of surgical staging at our institution, and such guidelines may be referenced by the institutions with sufficient gynecologic pathology expertise.