Primary Carcinoid Tumor of the Ovary: A Case Report With Radiologic and Pathologic Correlation

Ovarian carcinoid tumors are very rare entities that often mimic other ovarian neoplasms. A case of primary ovarian carcinoid in a 44-year-old woman is presented with emphasis on the magnetic resonance imaging (MRI) features of the tumor and pathologic correlation. Ovarian carcinoid tumors can be variable in their MRI appearance, presumably due to different tumor subtypes and tumor components, thus requiring pathologic diagnosis. It is imperative to accurately diagnose primary ovarian carcinoid tumors, as their prognosis is usually more favorable compared to other malignant ovarian neoplasms.

Malignant female genital tract smooth muscle tumors with adipocytic differentiation: A morphologic, immunohistochemical, MDM2 fluorescence in situ hybridization and molecular genetic study of 6 lipoleiomyosarcomas

Leiomyosarcoma with adipocytic differentiation or lipoleiomyosarcoma is an uncommon sarcoma of the female genital tract with only a few individual reports in the literature. We therefore performed a morphologic, immunohistochemical, MDM2 gene amplification and RNA and DNA sequencing analysis of a series of gynecologic lipoleiomyosarcoma to better define the clinicopathologic spectrum. Six tumors from 6 patients were identified and classified as spindled lipoleiomyosarcoma (n = 2), mixed spindled and myxoid lipoleiomyosarcoma (n = 1), epithelioid lipoleiomyosarcoma with focal myxoid features (n = 1) and mixed spindled and epithelioid lipoleiomyosarcoma (n = 2). Patient age ranged from 41 to 64 years (mean: 49; median: 50). Primary location included uterine corpus (3), uterine corpus/cervix (2) and broad ligament (1). Tumor size ranged from 4.5 to 22 cm (mean: 11.2; median: 9.8). Four patients had metastasis at presentation or subsequently developed recurrent or distant disease. Patient status was known for 5: 2 dead of disease, 2 alive with disease and 1 alive without evidence of disease. Immunohistochemical expression of smooth muscle markers, ER, PR and WT-1 showed patterns similar to non-adipocytic gynecologic leiomyosarcomas. MDM2 amplification fluorescence in situ hybridization performed on 2 tumors was negative in 1 and equivocal in 1. Sequencing studies performed on 3 tumors found TP53 mutations in 3, with 1 tumor also having an ATRX alteration. No gene fusions were identified. Although lipoleiomyosarcomas have a diverse morphologic spectrum, our findings suggest the smooth muscle component shares morphologic and immunohistochemical features with female genital tract non-adipocytic leiomyosarcomas. Lipoleiomyosarcomas also have genetic alterations associated with non-adipocytic gynecologic leiomyosarcomas.

Benign female genital tract smooth muscle tumors with adipocytic differentiation: A morphologic, immunohistochemical and MDM2 fluorescence in situ hybridization study of 44 conventional lipoleiomyomas and lipoleiomyoma variants

Leiomyomas with adipocytic differentiation typically occur in the uterus although they may arise at several sites in the female genital tract. While these are most commonly spindled leiomyomas with a component of adipocytic tissue ("conventional lipoleiomyomas"), there is a relatively ill-defined assortment of leiomyoma variants with adipocytic differentiation. We performed a morphologic, immunohistochemical and MDM2 gene amplification analysis of a large series of gynecologic leiomyomas with adipocytic differentiation to better define the clinicopathologic spectrum. Forty four tumors from 44 patients were identified and classified as conventional lipoleiomyoma (n = 21), adipocyte-rich lipoleiomyoma (defined as tumor volume >80 % adipocytes, n = 9); cellular lipoleiomyoma (n = 9); hydropic lipoleiomyoma (n = 3); and lipoleiomyoma with bizarre nuclei (n = 2). Patient age ranged from 32 to 83 years (mean 63; median 63). Primary location included uterine corpus (35), uterine cervix (3), uterine corpus/cervix (1), broad ligament (2), parametrium (2), and round ligament (1). Tumor size was 0.6-30 cm (mean 8; median 6). None of the 34 patients with follow up developed further disease (range 1-311 months; mean 65; median 41). Immunohistochemical expression of ER, PR, HMB45, Melan A, Cathepsin K and WT-1 in lipoleiomyomas and variants was similar to patterns in non-adipocytic gynecologic leiomyomas. MDM2 amplification fluorescence in situ hybridization performed on 14 tumors was negative in all. Our findings suggest female genital tract conventional lipoleiomyomas and lipoleiomyoma variants largely parallel their non-adipocytic counterparts in morphology and immunophenotype, and may be categorized using non-adipocytic leiomyoma histologic criteria.

Lipoblastoma-Like Tumor and Fibrosarcoma-Like Lipomatous Neoplasm Represent the Same Entity: A Clinicopathologic and Molecular Genetic Study of 23 Cases Occurring in Both Men and Women at Diverse Locations

Lipoblastoma-like tumor (LLT) is a benign soft tissue tumor demonstrating mixed morphologic features of lipoblastoma, myxoid liposarcoma, and spindle cell lipoma but lacking genetic alterations associated with those tumors. LLT was originally thought to be specific to the vulva but has since been reported in the paratesticular region. The morphologic features of LLT overlap with those of "fibrosarcoma-like lipomatous neoplasm" (FLLN), a rare, indolent adipocytic neoplasm considered by some to form part of the spectrum of atypical spindle cell and pleomorphic lipomatous tumor. We compared the morphologic, immunohistochemical, and genetic features of 23 tumors previously classified as LLT (n = 17) and FLLN (n = 6). The 23 tumors occurred in 13 women and 10 men (mean age, 42 years; range, 17 to 80 years). Eighteen (78%) cases arose in the inguinogenital region, whereas 5 tumors (22%) involved noninguinogenital soft tissue, including the flank (n = 1), shoulder (n = 1), foot (n = 1), forearm (n = 1), and chest wall (n = 1). Microscopically, the tumors were lobulated and septated, with variably collagenized fibromyxoid stroma, prominent thin-walled vessels, scattered univacuolated or bivacuolated lipoblasts, and a minor component of mature adipose tissue. Using immunohistochemistry, 5 tumors (42%) showed complete RB1 loss, with partial loss in 7 cases (58%). RNA sequencing, chromosomal microarray, and DNA next-generation sequencing study results were negative for significant alterations. There were no clinical, morphologic, immunohistochemical, or molecular genetic differences between cases previously classified as LLT or FLLN. Clinical follow-up (11 patients [48%]; range, 2-276 months; mean, 48.2 months) showed all patients were alive without disease, and only one patient had experienced a single local recurrence. We conclude that LLT and FLLN represent the same entity, for which "LLT" seems most appropriate. LLT may occur in either sex and any superficial soft tissue location. Careful morphologic study and appropriate ancillary testing should allow for the distinction of LLT from its potential mimics.

Detection of endometrial cancer using tampon-based collection and methylated DNA markers

OBJECTIVE

Alterations in DNA methylation are early events in endometrial cancer (EC) development and may have utility in EC detection via tampon-collected vaginal fluid.

METHODS

For discovery, DNA from frozen EC, benign endometrium (BE), and benign cervicovaginal (BCV) tissues underwent reduced representation bisulfite sequencing (RRBS) to identify differentially methylated regions (DMRs). Candidate DMRs were selected based on receiver operating characteristic (ROC) discrimination, methylation level fold-change between cancers and controls, and absence of background CpG methylation. Methylated DNA marker (MDM) validation was performed using qMSP on DNA from independent EC and BE FFPE tissue sets. Women ≥45 years of age with abnormal uterine bleeding (AUB) or postmenopausal bleeding (PMB) or any age with biopsy-proven EC self-collected vaginal fluid using a tampon prior to clinically indicated endometrial sampling or hysterectomy. Vaginal fluid DNA was assayed by qMSP for EC-associated MDMs. Random forest modeling analysis was performed to generate predictive probability of underlying disease; results were 500-fold in-silico cross-validated.

RESULTS

Thirty-three candidate MDMs met performance criteria in tissue. For the tampon pilot, 100 EC cases were frequency matched by menopausal status and tampon collection date to 92 BE controls. A 28-MDM panel highly discriminated between EC and BE (96% (95%CI 89-99%) specificity; 76% (66-84%) sensitivity (AUC 0.88). In PBS/EDTA tampon buffer, the panel yielded 96% (95% CI 87-99%) specificity and 82% (70-91%) sensitivity (AUC 0.91).

CONCLUSION

Next generation methylome sequencing, stringent filtering criteria, and independent validation yielded excellent candidate MDMs for EC. EC-associated MDMs performed with promisingly high sensitivity and specificity in tampon-collected vaginal fluid; PBS-based tampon buffer with added EDTA improved sensitivity. Larger tampon-based EC MDM testing studies are warranted.

Inflammatory Myofibroblastic Tumor of the Placenta With Subsequent Successful Pregnancy and Benign Hysterectomy: A Case Report With 59-Month Follow-up

Inflammatory myofibroblastic tumors (IMT) are rare neoplasms of intermediate malignant potential which have been described in the gynecologic tract, predominantly in the myometrial wall, but also in association with the placenta. Like those in other organs, IMT of the placenta are characterized by molecular abnormalities, most commonly anaplastic lymphoma kinase gene rearrangements, and are often positive for anaplastic lymphoma kinase immunohistochemically. Although the clinical behavior of placental IMTs has so far proven benign, a successful intrauterine pregnancy with subsequent negative hysterectomy following a placental IMT has not been documented. Herein is presented a case of a 27-yr-old noted to have a 2 cm IMT of the extraplacental membranes at delivery, after which the patient received no further treatment. After 56 mo, the patient experienced a subsequent normal delivery in a pregnancy complicated by gestational diabetes. No longer desiring fertility, the patient elected to have a hysterectomy to confirm the absence of IMT at 59 mo and the uterus was unremarkable. This case provides insight into possible outcomes for patients with a rare tumor who may desire future fertility and may otherwise be advised to undergo hysterectomy in the setting of an unclear clinical course.

Frequency of HER2 protein overexpression and HER2 gene amplification in endometrial clear cell carcinoma

HER2 (ERBB2) overexpression and/or HER2 gene amplification has been well established in several tumors types and when present HER2 directed therapy may be to be efficacious. While recent findings suggests that HER2 overexpression and HER2 amplification are a relatively common in serous endometrial carcinoma, similar data regarding clear cell endometrial carcinoma (CCC) is difficult to interpret due to issues such as diagnostic criteria, sample type and HER2 interpretation criteria. Our goals were to study HER2 expression and HER2 copy number status in hysterectomy specimens from a large series of patients with pure CCC to determine the frequency of HER2 overexpression and HER2 amplification and evaluate applicability of current HER2 interpretation criteria. Pure CCC specimens derived from hysterectomy specimens from 26 patients were identified. All diagnoses were confirmed by two gynecologic pathologists. Immunohistochemistry for HER2 protein and fluorescence in situ hybridization (FISH) studies for HER2 were performed on whole-slide sections from all cases. Results were interpreted according to the 2018 ASO/CAP HER2 guidelines for breast cancer and International Society of Gynecologic Pathologists (ISGyP) HER2 guidelines for serous endometrial carcinoma. Additional testing was performed when indicated by the guidelines. HER2 expression by immunohistochemistry was 3+ in 4% and 0% of cases, and 2+ in 46% and 52% of cases, by 2018 ASCO/CAP and ISGyP criteria, respectively, while the remaining cases were negative. HER2 testing by FISH showed a positive result in 27% of tumors with 2018 ASCO/CAP guidelines, while 23% were positive with the ISGyP criteria. Our findings indicate that HER2 overexpression and HER2 amplification occur in a subset of CCC. Therefore, additional study into the potential benefit of HER2 targeted therapy in patients with CCC is warranted.

Ovarian Signet-ring Stromal Tumor: A Morphologic, Immunohistochemical, and Molecular Study of 7 Cases With Discussion of the Differential Diagnosis

Signet-ring stromal tumor (SRST) is a rare ovarian stromal neoplasm characterized by a population of bland signet-ring cells, devoid of mucin or lipid, in a generally cellular fibromatous stroma. Previous reports have described heterogenous immunohistochemical and molecular genetic findings, including occasional nuclear β-catenin expression and/or CTNNB1 mutations. We report 10 ovarian stromal neoplasms originally diagnosed as SRST. All but 1 tumor underwent detailed immunohistochemical analysis (including β-catenin) and 5 of 10 had CTNNB1 mutation analysis performed. All tumors contained a population of morphologically bland signet-ring cells that ranged from 15% to 95% of the neoplasm, characterized by a single large empty intracytoplasmic vacuole, mostly with nuclear indentation. Six of the 10 tumors contained cellular fibroma-like areas, comprising from 10% to 85% of the neoplasm. Three of the 10 tumors were reclassified as microcystic stromal tumor with signet-ring cells on the basis of the microcyst formation and hyalinized stroma, beta-catenin and cyclin D1 nuclear expression and/or CTNNB1 mutation, CD10 staining and largely absent expression of inhibin and calretinin. In the remaining 7 tumors, the diagnosis of SRST remained, constituting the largest series of SRST reported in the literature to date. The results of our study suggest that a subset of tumors diagnosed as ovarian SRST, especially those which show β-catenin nuclear positivity and/or CTNNB1 mutation, likely represent microcystic stromal tumor with variant morphology. We also suggest that at least a subset of SRSTs without evidence of Wnt/β-catenin pathway abnormalities may be related to ovarian fibromas. We discuss the differential diagnosis of ovarian neoplasms containing signet-ring cells.

Association Between Laparoscopic Appearance of Superficial Endometriosis, Positive Histology, and Systemic Hormone Use

STUDY OBJECTIVE

To assess the association between laparoscopic appearance of superficial endometriosis lesions, histopathology, and systemic hormone use.

DESIGN

Retrospective study.

SETTING

Tertiary care academic medical center.

PATIENTS

We identified 266 women who underwent laparoscopic surgery at an endometriosis center with excision of lesions consistent with possible superficial endometriosis between September 2015 and November 2018.

INTERVENTIONS

Appearance of the peritoneal lesions was confirmed with review of surgical videos and correlated with each pathology specimen. Lesions were dichotomized on positive or negative pathology assessment. All pathology-positive lesions were further dichotomized by hormone use within 1 month of surgery.

MEASUREMENTS AND MAIN RESULTS

A total of 841 lesions were biopsied from included subjects during the study period. Of those, 251 biopsies were negative, and 590 were positive for endometriosis on pathology assessment. Lesions had significantly higher odds of positive histology when they were red (odds ratio [OR], 1.70; 95% confidence interval [CI], 1.17-2.48), white (OR, 1.99; 95% CI, 1.47-2.70), blue/black (OR, 2.98; 95% CI, 2.00-4.44), or puckering (OR, 9.78; 95% CI, 2.46-38.91) in appearance. The following combined characteristics had significantly higher odds of positive histology: white and blue (OR, 5.98; 95% CI, 2.97-12.02), red and white (OR, 2.22; 95% CI, 1.38-3.56), red and blue (OR, 4.11; 95% CI, 1.83-9.24), and clear and white (OR, 8.77; 95% CI, 1.17-66.02). Among positive biopsies, those with hormone exposure were more likely to have clear lesions than those without hormone use (OR, 3.36; 95% CI, 1.54-7.34) and were 2.89 times more likely to have clear and white lesions (95% CI, 1.07-7.85).

CONCLUSION

Although lesions suspicious for endometriosis may have differing rates of positive pathology based on appearance, no lesion characteristic was able to exclude the possibility of endometriosis. In addition, hormone use may influence lesion appearance at the time of surgery, with clear lesions more prevalent. These data have implications for appropriate identification of endometriosis at the time of laparoscopy to ensure accurate diagnosis and complete treatment of disease.

Bizarre Chorionic-type Trophoblast in Second-trimester and Third-trimester Placentas: Clinicopathologic Characterization of a Placental Pseudoneoplastic Lesion

Bizarre (atypical/symplastic) cells have been described in various gynecologic normal tissues and benign neoplasms. This type of bizarre cytologic change is usually an incidental finding and is regarded as a benign process. We describe 17 cases of bizarre chorionic-type trophoblast in second-trimester and third-trimester placentas that created concern for an underlying/undersampled or incipient intraplacental trophoblastic neoplasm, predominantly found in intervillous trophoblastic islands (11/17), placental septae (6/17), chorionic plate (1/17), and/or the chorion layer of fetal membranes (2/17). The bizarre trophoblastic cells exhibited sheet-like or nested architecture, had a multifocal/patchy distribution, and/or were present as individual cells within hyaline stroma; they were characterized by large nuclei with smudgy chromatin and occasional intranuclear pseudoinclusions. The degree of atypia was classified as mild (0/17), moderate (3/17), or severe (14/17). Mitotic figures and necrosis were not identified. A dual immunohistochemical stain for trophoblast (hydroxyl-delta-5-steroid dehydrogenase) and a proliferation marker (Ki-67), performed in 15 cases, demonstrated 0% to very low proliferative activity within the bizarre trophoblast (0% to 2% [10/15], 3% to 8% [5/15]). Immunohistochemical stains for fumarate hydratase showed intact/retained expression in the bizarre cells in 7 of 7 cases. Clinical follow-up ranged from 1 to 45 months, and all patients were alive and well without subsequent evidence of a gestational trophoblastic or other neoplasms. We conclude that bizarre chorionic-type trophoblast in second-trimester or third-trimester placentas have the potential to mimic an intraplacental trophoblastic neoplasm but are likely a benign degenerative change. This study expands the spectrum of bizarre cells that occur in the gynecologic tract.

A case of a large leiomyomatous uterus with multiple arteriovenous malformations and subsequent high cardiac output state with severe four chamber cardiac enlargement

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Uterine arteriovenous malformations (AVMs) may be associated with leiomyomas.

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Uterine AVMs can lead to a high cardiac output state and cardiac dysfunction.

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Multidisciplinary management of uterine AVMs may prevent high output cardiac failure.

Uterine arteriovenous malformations (AVMs) are rare and potentially life-threatening. They can be congenital or acquired. Uterine artery embolization or hysterectomy are considered mainstays of management. AVMs can be associated with leiomyomas, and patients may require both procedures. We present a case of a 42-year-old woman with a massively enlarged leiomyomatous uterus supplied and drained by multiple large AVMs, leading to high cardiac output state with severe four chamber cardiac dilation. Management required a multidisciplinary team of interventional radiology, gynecologic oncology surgery, vascular surgery, cardiac anesthesiology, cardiology, and urology and a 2-day interventional approach of preoperative arterial embolization followed by hysterectomy.

EWSR1-WT1 gene fusions in neoplasms other than desmoplastic small round cell tumor: a report of three unusual tumors involving the female genital tract and review of the literature

Desmoplastic small round cell tumor (DSRCT) is a high-grade round cell sarcoma that typically arises in the abdominopelvic cavity of young males, co-expresses keratins and desmin, and carries a pathognomonic EWSR1-WT1 gene fusion. The EWSR1-WT1 gene fusion is generally considered specific for DSRCT, although there are two reports of this fusion in tumors otherwise lacking features of DSRCT. We report three female genital tract tumors with EWSR1-WT1 fusions but showing morphologic and immunohistochemical features incompatible with DSRCT. The tumors occurred in the uterine cervix, uterine corpus/ovaries, and vagina, respectively, of 46, 30, and 20-year-old women. Two tumors consisted of a sheet-like to fascicular proliferation of relatively uniform spindled to occasionally more epithelioid cells arrayed about thick-walled, hyalinized, and capillary-sized vessels, with distinctive areas of pseudovascular change, and absence of desmoplastic stroma. The third tumor resembled a monomorphic spindle cell sarcoma with necrosis. All had diffuse desmin and variable but more limited keratin expression, two of three expressed smooth muscle actin, and all were negative for h-caldesmon, CD10, estrogen receptor, myogenin, N-terminus WT-1, and S100 protein. One patient received neoadjuvant chemotherapy and radiation therapy followed by resection and is disease-free 42 months after diagnosis. Another patient was managed by resection only and is disease-free 9 months after initial diagnosis. The remaining patient recently underwent resection of multifocal pelvic disease. Comprehensive differential gene expression analysis on two tumors compared to two classic DSRCTs with known EWSR1-WT1 fusions resulted in 1726 genes that were differentially expressed (log2 fold change >2 or < -2) and statistically significant (FDR < 5%). In combination with previous reports, our findings suggest pleiotropy of the EWSR1-WT1 fusion is possible and not limited to DSRCT. Subsets of non-DSRCT EWSR1-WT1 positive tumors may represent discrete entities, but further study is necessary.

A Distinctive Adnexal (Usually Paratubal) Neoplasm Often Associated With Peutz-Jeghers Syndrome and Characterized by STK11 Alterations (STK11 Adnexal Tumor): A Report of 22 Cases

We describe 22 examples of a novel, usually paratubal, adnexal tumor associated with Peutz-Jeghers syndrome in nearly 50% of cases that harbored STK11 alterations in all tested (n=21). The patients ranged from 17 to 66 years (median=39 y) and the tumors from 4.5 to 25.5 cm (median=11 cm). Most (n=18) were paratubal, with metastases noted in 11/22 (50%) and recurrences in 12/15 (80%). Morphologically, they were characterized by interanastomosing cords and trabeculae of predominantly epithelioid cells, set in a variably prominent myxoid to focally edematous stroma, that often merged to form tubular, cystic, cribriform, and microacinar formations, reminiscent of salivary gland-type tumors. The tumor cells were uniformly atypical, often with prominent nucleoli and a variable mitotic index (median=9/10 HPFs). The tumors were usually positive to a variable extent for epithelial (CAM5.2, AE1/AE3, cytokeratin 7), sex cord (calretinin, inhibin, WT1), and mesothelial (calretinin, D2-40) markers, as well as hormone receptors. PAX8, SF1, and GATA-3 were rarely positive, while claudin-4, FOXL2, and TTF-1 were consistently negative. All sequenced tumors (n=21) harbored alterations in STK11, often with a loss of heterozygosity event. There were no other recurrently mutated genes. Recurrent copy number alterations included loss of 1p and 11q, and gain of 1q, 15q, and 15p. Despite an extensive morphologic, immunohistochemical, and molecular evaluation, we are unable to determine with certainty the histogenesis of this unique tumor. Wolffian, sex cord stromal, epithelial, and mesothelial origins were considered. We propose the term STK11 adnexal tumor to describe this novel entity and emphasize the importance of genetic counseling in these patients as a significant number of neoplasms occur in association with Peutz-Jeghers syndrome.

Discovery and validation of novel methylated DNA markers of cervical cancer

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Background: HR-HPV DNA testing, with or without cervical cytology, provides excellent sensitivity for detection of cervical cancer (CC) and its precursors; negative test results indicate that risk of disease is extremely low and enable women to undergo reduced screening with safety. However, management of women who screen positive remains challenging as many will prove to have self-limited HR-HPV infections. DNA methylation is an early event in carcinogenesis that could enhance CC screening specificity. Methods: For discovery, DNA from 70 FFPE CC (36 squamous, 34 adenocarcinoma) tissues that were reviewed microscopically, 18 fresh frozen benign cervicovaginal (BCV) tissues collected at the time of benign hysterectomy, and 18 buffy coats from cancer-free women underwent reduced representation bisulfite sequencing (RRBS) to identify MDMs associated with CC. Candidate MDM selection was based on area under the receiver operating characteristic curve (AUC) discrimination, methylation fold change, and low background methylation among benign controls. Candidate MDMs were re-tested using methylation-specific PCR (MSP) to confirm performance. Blinded biological validation was performed using MSP on DNA extracted from independent FFPE CC (38 squamous, 43 adenocarcinoma) and BCV (40) tissues. The performance of CC MDMs was also tested in DNA extracted from cervical dysplasia (36 adenocarcinoma in situ (AIS), 32 cervical intraepithelial neoplasia (CIN) 2/3, 11 CIN 1) FFPE tissues. Results: From RRBS discovery and technical validation via MSP, 30 candidate MDMs showed marked methylation fold changes (10 to >1000) across both CC histologies compared to BCV tissue from cancer-free women. Each of the 30 MDMs highly discriminated CC from BCV tissue with 9 MDMs having an AUC >0.90 (Table). CC MDMs also highly discriminated AIS from BCV but did not perform well in CIN 2/3 and CIN 1 (Table). Conclusions: Whole methylome sequencing, stringent filtering criteria, and biological validation have yielded outstanding candidate MDMs for CC that highly discriminate CC from BCV, notably with high specificity. Performance in cervical dysplasias varied with higher positivity rates in AIS than in CIN 2/3 and CIN 1. Translation to testing these novel MDMs in lower genital tract biospecimens and the addition of HR-HPV to the CC panel are warranted.[Table: see text]

Methylated DNA markers for plasma detection of ovarian cancer: Discovery, validation, and clinical feasibility

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Background: Effective screening tests for ovarian cancer (OC) are lacking; most cases present at advanced stage and portend poor prognosis. DNA methylation is an early event in carcinogenesis and can be detected in blood plasma samples from cancer patients. In DNA extracted from tissues, we first discovered, then validated discriminant methylated DNA marker (MDM) candidates for OC and subsequently tested independent plasma from women with and without OC. Methods: For discovery, DNA from 67 frozen tissues (18 high grade serous (HGS), 18 endometrioid, 15 clear cell (CC), 6 mucinous OCs; 10 benign fallopian tube epithelium (FT); and 19 buffy coats from cancer-free women underwent reduced representation bisulfite sequencing (RRBS) to identify MDMs associated with OC. Candidate MDM selection was based on receiver operating characteristic (ROC) discrimination, methylation fold change, and low background methylation among controls. Blinded biological validation was performed using methylated specific PCR on DNA extracted from independent FFPE tissues from OCs (36 HGS, 22 endometrioid, 21 CC, and 14 mucinous) and 29 FT. Top performing MDMs in tissue were tested using long-probe quantitative amplified signal assays in independent pre-treatment plasma samples from women newly-diagnosed with OC and population-sampled healthy women. A random forest modeling analysis was performed to generate predictive probability of disease; results were 500-fold in silico cross-validated. Results: After RRBS discovery and biological validation, 33 MDMs showed marked methylation fold changes (10 to > 1000) across all OC histologies vs FT. The top 11 MDMs ( GPRIN1, CDO1, SRC, SIM2, AGRN, FAIM2, CELF2, DSCR6, GYPC, CAPN2, BCAT1) were tested on plasma from 91 women with OC (76 (84%) HGS) and 91 without OC; the cross-validated 11-MDM panel highly discriminated OC from controls (96% (95%CI 89-99%) specificity; 79% (69-87%) sensitivity, and AUC 0.91 (0.86 - 0.96)). Among HGS, the panel correctly identified 83%, including 5/6 stage I/II, and the majority of other subtypes (Table). Conclusions: Whole methylome sequencing, stringent filtering criteria, and biological validation yielded outstanding candidate MDMs for OC that performed with promisingly high sensitivity and specificity in plasma. Larger plasma-based OC MDM testing studies, with larger numbers of non-HGS histologies are warranted. [Table: see text]

Endoscopic Resection of a Pediatric Carcinoid Lung Tumor Presenting as Persistent Pneumonia

Primary lung tumors are very rare in children and constitute only 0.2 percent of all pediatric malignancies. Carcinoids are the most common primary pediatric lung tumor and account for 80 percent of all primary malignant bronchial tumors. Carcinoid tumors can be histologically categorized as typical or atypical. They are derived from neuroendocrine cells in the bronchial epithelium and are locally infiltrative. Surgical resection of endobronchial carcinoid tumors is the mainstay of treatment with a five-year survival of 95 percent. Endoscopic resection has been reported in adult patients with typical carcinoid tumors (less than 20 mm) with no extrabronchial disease. We present the first pediatric bronchial carcinoid tumor treated with endoscopic resection.

Leiomyoma with KAT6B-KANSL1 fusion: case report of a rapidly enlarging uterine mass in a postmenopausal woman

Background

Uterine leiomyomas, in contrast to sarcomas, tend to cease growth following menopause. In the setting of a rapidly enlarging uterine mass in a postmenopausal patient, clinical distinction of uterine leiomyoma from sarcoma is difficult and requires pathologic examination.

Case presentation

A 74-year-old woman presented with postmenopausal bleeding and acute blood loss requiring transfusion. She was found to have a rapidly enlarging uterine mass clinically suspicious for sarcoma. An abdominal hysterectomy and bilateral salpingo-oophorectomy were performed. A 15.5 cm partially necrotic intramural mass was identified in the uterine corpus. The tumor was classified as a cellular leiomyoma. RNA sequencing identified a KAT6B-KANSL1 fusion that was confirmed by RT-PCR and Sanger sequencing. After 6 months of follow-up, the patient remains asymptomatic without evidence of disease.

Conclusion

Prior studies of uterine leiomyomas have identified KAT6B (previously MORF) rearrangements in uterine leiomyomas, but this case is the first to identify a KAT6B-KANSL1 gene fusion in a uterine leiomyoma. While alterations of MED12 and HMGA2 are most common in uterine leiomyomas, a range of other genetic pathways have been described. Our case contributes to the evolving molecular landscape of uterine leiomyomas.

Florid cystic endosalpingiosis with uterine preservation and successful assisted reproductive therapy

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While endosalpingiosis is often asymptomatic & incidental, florid cystic endosalpingiosis can have a variable presentation

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Cystic endosalpingiosis can be difficult to differentiate from other non-neoplastic peritoneal inclusion cysts

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Although associated with serous pelvic neoplasms, there is no evidence for oophorectomy at the completion of fertility

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There is no strong evidence that hysterectomy along with cyst resection leads to improved outcomes if pathology is benign

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This is the first reported case of successful assisted-reproductive therapy after resected florid cystic endosalpingiosis

HER2 gene amplification and protein overexpression in uterine clear cell carcinoma and its implications in targeted immunotherapy

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Background: Uterine clear cell carcinoma (UCCC) is a high-grade endometrial carcinoma. The current treatment is hysterectomy with post-operative chemotherapy and/or radiation. The 5-year disease free survival remains dismal for UCCC with 65% for early-stage and 54% for advanced stage disease. In addition, UCCC may be more resistant to chemotherapy or radiation therapy than the endometrioid subtype. The aim of the current study is to investigate the HER2 gene amplification status in UCCC and its role for targeted therapy in UCCC. Methods: Twenty-nine cases of UCCC were retrieved from surgical pathology archives of Mayo Clinic at Rochester between 2011 and 2015. All cases except one case were hysterectomy specimens. The blocks contain the most characteristic morphology of UCCC were selected and corresponding paraffin sections were subjected to fluorescent in situ hybridization for amplification of HER2 gene (Hercept, Abbott Molecular) and parallel immunohistochemical (IHC) study. Results: A total of 9 (of 29; 31%) UCCCs showed HER2 amplification and 4 (of 29; 14%) were considered equivocal for HER2 amplification by FISH. A total of 3 (10%) tumors showed 3+ HER2 overexpression while 11 (38%) UCCCs showed 2+ HER2 overexpression, 9 (31%) showed 1+ expression with the remaining cases showing no expression of HER2. Importantly, we observed significant intratumoral heterogeneity with regard to HER2 expression. Comparing the results of IHC with HER2 gene status as determined by FISH, 2 (66%) of the 3 cases that showed 3+ HER2 expression also showed amplification for HER2 by FISH, while 1 (33%) was equivocal for HER2 amplification. Of the 11 tumors that showed 2+ HER2 expression, 6 (55%) were amplified by FISH and 1 (9%) was equivocal. Conclusions: This is the largest number of UCCC cases that has been studied on the HER2 amplification and corresponding protein overexpression. Our results indicate that the HER2 overexpression is common in UCCCs and is frequently associated with HER2 amplification. These results also suggest that targeted adjuvant therapy with trastuzumab-based immunotherapy should be evaluated in patients with UCCC showing HER2 protein overexpression or HER2 gene amplification.