Kaori Sanuki

Microsatellite instability is a biomarker for immune checkpoint inhibitors in endometrial cancer

In recent years, it has become evident that tumor cells have immune escape mechanisms, and immune checkpoint inhibitor therapy (anti-PD-1/PD-L1 antibody) has shown benefit in various cancers. In endometrial tumors with microsatellite-instability (MSI), somatic mutations have the potential to encode ‘’non-self’’ immunogenic antigens, and lymphocytes have been shown to infiltrate the tumor. Therefore, immune checkpoint inhibitor therapy might be effective in endometrial cancers with MSI. Expression of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6), the presence of tumor-infiltrating lymphocytes (CD8+), and PD-1/PD-L1 expression were assessed by immunohistochemistry in 149 patients with endometrial cancer. We examined whether tumors with MSI had an enhanced immune microenvironment and whether MSI could be a predictor of the therapeutic effect of PD-1/PD-L1 immunotherapy in endometrial cancer. Loss of MMR protein expression was identified in 42 (28.2%) of 149 patients (MSI group) with endometrial cancer. There was no significant relationship between MSI status and age (p = 0.193), histological grade (p = 0.097), FIGO stage (p = 0.508), pelvic lymph node metastasis (p = 0.139), or depth of myometrial invasion (p = 0.494). However, the presence of tumor-infiltrating lymphocytes (CD8+) and PD-L1/PD-1 expression were significantly higher in the MSI group compared to the microsatellite-stable group (p = 0.002, p = 0.001, and p = 0.008, respectively). These results suggest that immune checkpoint inhibitors (anti-PD-1/PD-L1 antibody) could be effective in endometrial cancers with MSI. The presence of MSI may be a biomarker for good response to PD-1/PD-L1 immunotherapy in endometrial cancer.

KRAS/BRAF Analysis in Ovarian Low-Grade Serous Carcinoma Having Synchronous All Pathological Precursor Regions

Ovarian low-grade serous carcinoma is thought to begin as a serous cystadenoma or adenofibroma that progresses in a slow stepwise fashion. Among the low-grade serous carcinomas, there is a high frequency of activating mutations in the KRAS or BRAF genes; however, it remains unclear as to how these mutations contribute to tumor progression. This is the first report to track the histopathological progression of serous adenofibroma to low-grade serous carcinoma. Each stage was individually analyzed by pathological and molecular genetic methods to determine what differences occur between the distinct stages of progression.

Affinity-purified DNA-based mutation profiles of endometriosis-related ovarian neoplasms in Japanese patients

Aim Endometriosis-related ovarian neoplasms (ERONs) have recently attracted considerable attention; however, the prevalence and patterns of ARID1A and POLE mutations in ERONs have not been studied in detail. The aim of this study was to investigate not only the carcinogenesis of ERONs, but also the prognostic significance of several gene mutations in this cohort. We used DNA purified from only tumor epithelial cells, from which fibroblasts were removed, using a specific method we called “liquid microdissection”. Methods Tissue samples from 22 ovarian carcinomas (13 endometrioid, and nine clear cell) were used. Tumor cells were isolated using a cell sorting system and DNA was purified from tumor epithelial cells. Nucleotide sequencing was conducted to analyze the mutational status of ARID1A, p53, PTEN, POLE, PIK3CA, and KRAS. Results In ERONs, the frequencies of somatic mutations in ARID1A, p53, POLE, PTEN, PIK3CA, and KRAS were 19/20 (95.0%), 7/19 (36.8%), 9/22 (40.9%), 13/19 (68.4%), 3/19 (15.8%), and 1/9 (11.1%). The frequency of ARID1A mutations was significantly higher than that reported previously. Kaplan-Meier survival analysis revealed that mutations in all genes, including POLE, were not associated with patient prognosis in our Japanese cohort. Conclusions Our results suggest that the frequency of ARID1A mutations in ERONs may be higher than that previously reported. In addition, the “liquid microdissection” method that we chose for DNA purification could be used to obtain high-quality sequencing results. The findings suggest that ARID1A mutations represent the basis of ERON carcinogenesis; other subsequent gene mutations may result in the progression of carcinogenesis.

Long‑term outcomes of microwave endometrial ablation for treatment of patients with menorrhagia: A retrospective cohort study

This study aimed to describe the long-term outcomes of patients with menorrhagia treated with microwave endometrial ablation (frequency, 2.45 GHz), as well as to identify factors associated with recurrence or re-surgery. This retrospective cohort study was conducted from 2007 to 2015 at Shimane University Hospital in Japan. Patients with severe menorrhagia and a desire to preserve their uterus were included in the study. Clinical factors associated with recurrence of menorrhagia or re-surgery were analyzed with a multivariable logistic regression model. Of 160 microwave endometrial ablation candidates, 100 had uterine myomas, 20 adenomyosis, 26 functional excessive menstruation, and 12 endometrial polyps. In the full cohort, age (<40) and uterine cavity length (≥10) were associated with recurrence of menorrhagia and re-surgery. Among patients with myomas, age (<48) and number of myomas (≥4) were associated with recurrence, and largest myoma size (≥5) and preoperative hemoglobin level (<9 mg/dl) were associated with re-surgery. Among subjects with adenomyosis, uterine cavity length (≥10) was associated with recurrence. Microwave endometrial ablation is thought to be a highly efficacious method to control menorrhagia caused by functional bleeding and endometrial polyps. However, microwave endometrial ablation may be less effective for patients younger than 48 years with myomas, especially those with 4 or more myomas, or with a myoma 5 cm or larger in size, and for patients with adenomyosis who have a thickened myometrium. These clinical factors may be useful predictors of success in selecting candidates for microwave endometrial ablation.

Genetic analysis and phosphoinositide 3‑kinase/protein kinase B signaling pathway status in ovarian endometrioid borderline tumor samples

Ovarian endometrioid borderline tumors (EBTs) are extremely rare, and are thought to be precursors of endometrioid carcinoma, beginning as adenofibroma or endometriosis and progressing in a slow, stepwise manner. In endometrioid carcinomas, a high frequency of activating mutations in phosphatase and tensin homolog (PTEN), β-catenin or AT-rich interaction domain 1A (ARID1A) genes, and the activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway have been observed. However, the frequency of these alterations in EBTs and how they contribute to tumor progression remain unclear. To the best of our knowledge, this is the first study to assess the status of the PI3K/AKT signaling pathway in EBTs, in association with PTEN and ARID1A mutations. PTEN mutations were observed in EBTs and also in the area of endometriosis without atypia. However, the PI3K/AKT signaling pathway was revealed to be activated only in EBTs. The observations of the present study suggest that the PTEN mutation represents an early event in EBT tumorigenesis, while additional genetic alterations may be necessary to activate the PI3K/AKT signaling pathway and induce the development of the invasive carcinoma.

High preoperative Glasgow prognostic score is a negative prognostic factor for patients with endometrial carcinoma

The aim of the present study was to determine the prognostic value of the Glasgow prognostic score (GPS) in endometrial carcinoma (EC). Patients with EC who underwent surgery at the Shimane University Hospital between January 1997 and December 2013 were enrolled (n=118). The associations between pretreatment GPS and clinical parameters, including age, histological type, International Federation of Gynecology and Obstetrics stage, tumor grade, carbohydrate antigen 19-9 and carcinoembryonic antigen levels, progression-free survival (PFS), and overall survival (OS), were investigated. Survival analysis was performed with the Kaplan-Meier method, and prognostic factors were evaluated with Coxs proportional hazards regression model. A high pretreatment GPS was associated with advanced clinical stage, histological type and tumor grade (P<0.001, P=0.007 and P=0.006, respectively). Multivariate analysis identified a high GPS as an independent negative prognostic factor for PFS and OS (P=0.025 and P=0.044, respectively). Therefore, a high pretreatment GPS has prognostic value and the potential to be a predictive marker for surgical outcome in patients with EC. Evaluation of pretreatment GPS may aid in the identification of high-risk populations, which may improve treatment selection and patient outcomes.

Loss of beclin 1 expression in ovarian cancer: A potential biomarker for predicting unfavorable outcomes

The clinicopathological significance and prognostic value of the expression of proteins associated with autophagy, beclin 1 (BECN1), 1A/1B-light chain 3 (LC3) and high mobility group box-1 protein (HMGB-1), were investigated in patients with ovarian carcinoma, receiving combination chemotherapy with a platinum agent and a taxane. Immunohistochemical staining was performed for autophagy-associated proteins in tumor tissues from 141 patients with ovarian carcinoma. Clinical data were collected retrospectively by reviewing medical charts, and the association between protein expression, clinicopathological features and survival was investigated. Amongst 141 ovarian carcinoma samples, the loss of BECN1, LC3, and HMGB-1 expression was identified in 59 (41.8%), 35 (24.8%), and 66 (46.8%) samples, respectively. Clinicopathological factors were not significantly associated with the loss of BECN1 expression. However, significant associations were demonstrated between the expression of BECN1, LC3, and HMGB-1. In addition, loss of BECN1 expression demonstrated a significant association with poor progression-free and poor overall survival. Multivariate analysis demonstrated that loss of BECN1 expression and postoperative residual tumor were significant independent predictors of poor progression-free survival and poor overall survival. These results indicated that loss of BECN1 expression in ovarian carcinoma is a negative prognosticator in patients receiving platinum-based chemotherapy. Assessment of BECN1 expression may be useful for predicting an unfavorable response to platinum-based chemotherapy in ovarian carcinoma.

Metastasis of breast cancer to an endometrial polyp, the cervix and a leiomyoma: A case report and review of the literature

Haematogenous metastases of breast cancer tumors has previously been demonstrated to frequently occur at the sites of the lung, bones, liver and brain, however presence in the uterine remains a rare occurrence. Metastatic carcinoma of the uterus usually originates from other genital sites, most frequently from the ovaries. The current review presents the first reported case of lobular breast carcinoma metastasizing to an endometrial polyp, the cervix and a leiomyoma simultaneously. The patient (58 years, female) first presented with abnormal uterine bleeding. Invasive ductal carcinoma had previously been diagnosed in her right breast, with lobular and ductal cancer cells observed to be present in her lymph nodes. A hysteroscopic procedure to examine the postmenopausal bleeding revealed an endometrial polyp, which was subsequently resected. The morphology and immunohistochemical studies confirmed the diagnosis of metastasis of lobular breast carcinoma to an endometrial polyp. An 18F fludeoxyglucose positron emission tomography/computed tomography (PET-CT) scan performed following the diagnosis, revealed a slightly increased uptake in the myoma, which is often observed in benign uterine leiomyoma. The patient then underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy and partial colectomy. Pathology results demonstrated that the uterine leiomyoma and cervix shared the same histopathological features as those presented by the primary lobular breast carcinoma. Although rare, breast tumors may metastasize to an endometrial polyp, cervix and leiomyoma concurrently in patients, therefore physicians may now consider the potential of the diagnosis of metastatic spread to the genital tract, in a patient with abnormal uterine bleeding and a history of lobular breast cancer. Gynecologists planning a laparoscopic hysterectomy for a patient with a history of lobular breast carcinoma may consider abdominal rather than laparoscopic hysterectomy, as lobular carcinoma is difficult to detect. The use of PET-CT may be beneficial for the identification of an unexpected mass.

Total laparoscopic hysterectomy for large uterine cervical myoma

Ureterolysis is a surgical method with a high level of difficulty, which may be necessary when performing total laparoscopic hysterectomy (TLH) for large cervical myoma, despite the benign nature of this tumor. The aim of the present study was to introduce techniques that are commonly applied in malignant tumor surgery in order to safely perform TLH for large cervical myoma. Between 2014 and 2016, TLH was performed at the Shimane University Hospital (Izumo, Japan) in 153 patients with benign tumors, including 25 cases with a large uterus (uterine weight ≥500 g). The surgical methods applied in 3 of these large uterine cervical myoma cases were investigated in detail, including techniques devised by our department. TLH was performed without enucleating myomectomy in all 3 cases; however, all 3 cases required ureterolysis, transection of the anterior layer of the vesicouterine ligament and isolation of the ureter. In conclusion, although radical laparoscopic hysterectomy is commonly performed for cervical cancer at our department, techniques used for malignant tumor surgery may prove useful for benign cases with a high level of difficulty.

Abstract 2621: Microsatellite instability is a potential biomarker for immune checkpoint inhibitor in endometrial cancer

[Introduction] In recent years, tumor cells have immune escape mechanism and immune checkpoint inhibitor therapy (anti PD-1/ PD-L1 antibody) has shown benefit in various cancers. Somatic mutations have the potential to encode ‘’non-self’’immunogenic antigens and lymphocytes infiltrate tumor cells in Microsatellite-instable (MSI) endometrial cancers. Therefore, immune checkpoint inhibitor therapy might be effective in MSI endometrial cancers. [Method] Mismatch repair protein (MLH1, PMS2, MSH2, and MSH6), tumor-infiltrating lymphocytes (CD8), and PD-1/PD-L1 expression were assessed by immunohistochemistry in 60 patients with endometrial cancer. We examined whether MSI status have enhanced immune microenvironment and become the therapeutic effect predictor of PD-1/PD-L1 immunotherapy in endometrial cancer. [Results] Loss of mismatch repair protein (MSI group) was identified in 8 (13.3 %) of 60 patients with endometrial cancer. Expression of tumor-infiltrating lymphocytes (CD8) and PD-L1/PD-1 were significantly higher in MSI group compared to MSS group (p=0.001, p=0.044 and p=0.013). [Conclusion]These results suggested that immune checkpoint inhibitor (anti PD-1/PD-L1 antibody) is effective in endometrial cancers with MSI. MSI testing is likely to be a biomarker for PD-1/PD-L1 immunotherapy in endometrial cancer. Citation Format: Hitomi Yamashita, Kentaro Nakayama, Noriyoshi Ishikawa, Toshiko Minamoto, Tomoka Ishibashi, Kohei Nakamura, Kaori Sanuki, Ruriko Ono, Masako Ishikawa, Takeshi Isobe, Satoru Kyo. Microsatellite instability is a potential biomarker for immune checkpoint inhibitor in endometrial cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2621. doi:10.1158/1538-7445.AM2017-2621