High-Grade Endometrial Cancer: Molecular Subtypes, Current Challenges, and Treatment Options.

Although many recent advancements have been made in women's health, perhaps one of the most neglected areas of research is the diagnosis and treatment of high-grade endometrial cancer (EnCa). The molecular classification of EnCa in concert with histology was a major step forward. The integration of profiling for mismatch repair deficiency and Human Epidermal Growth Factor 2 (HER2) overexpression, can further inform treatment options, especially for drug resistant recurrent disease. Recent early phase trials suggest that regardless of subtype, combination therapy with agents that have distinct mechanisms of action is a fruitful approach to the treatment of high-grade EnCa. Unfortunately, although the importance of diagnosis and treatment of high-grade EnCa is well recognized, it is understudied compared to other gynecologic and breast cancers. There remains a tremendous need to couple molecular profiling and biomarker development with promising treatment options to inform new treatment strategies with higher efficacy and safety for all who suffer from high-grade recurrent EnCa.

Targeting Galectin 3 illuminates its contributions to the pathology of uterine serous carcinoma.

BACKGROUND: Uterine serous cancer (USC) comprises around 10% of all uterine cancers. However, USC accounts for approximately 40% of uterine cancer deaths, which is attributed to tumor aggressiveness and limited effective treatment. Galectin 3 (Gal3) has been implicated in promoting aggressive features in some malignancies. However, Gal3's role in promoting USC pathology is lacking. METHODS: We explored the relationship between LGALS3 levels and prognosis in USC patients using TCGA database, and examined the association between Gal3 levels in primary USC tumors and clinical-pathological features. CRISPR/Cas9-mediated Gal3-knockout (KO) and GB1107, inhibitor of Gal3, were employed to evaluate Gal3's impact on cell function. RESULTS: TCGA analysis revealed a worse prognosis for USC patients with high LGALS3. Patients with no-to-low Gal3 expression in primary tumors exhibited reduced clinical-pathological tumor progression. Gal3-KO and GB1107 reduced cell proliferation, stemness, adhesion, migration, and or invasion properties of USC lines. Furthermore, Gal3-positive conditioned media (CM) stimulated vascular tubal formation and branching and transition of fibroblast to cancer-associated fibroblast compared to Gal3-negative CM. Xenograft models emphasized the significance of Gal3 loss with fewer and smaller tumors compared to controls. Moreover, GB1107 impeded the growth of USC patient-derived organoids. CONCLUSION: These findings suggest inhibiting Gal3 may benefit USC patients.

Inhibition of the proline metabolism rate-limiting enzyme P5CS allows proliferation of glutamine-restricted cancer cells.

Glutamine is a critical metabolite for rapidly proliferating cells as it is used for the synthesis of key metabolites necessary for cell growth and proliferation. Glutamine metabolism has been proposed as a therapeutic target in cancer and several chemical inhibitors are in development or in clinical trials. How cells subsist when glutamine is limiting is poorly understood. Here, using an unbiased screen, we identify ALDH18A1, which encodes P5CS, the rate-limiting enzyme in the proline biosynthetic pathway, as a gene that cells can downregulate in response to glutamine starvation. Notably, P5CS downregulation promotes de novo glutamine synthesis, highlighting a previously unrecognized metabolic plasticity of cancer cells. The glutamate conserved from reducing proline synthesis allows cells to produce the key metabolites necessary for cell survival and proliferation under glutamine-restricted conditions. Our findings reveal an adaptive pathway that cancer cells acquire under nutrient stress, identifying proline biosynthesis as a previously unrecognized major consumer of glutamate, a pathway that could be exploited for developing effective metabolism-driven anticancer therapies.

The evolving role of DNA damage response in overcoming therapeutic resistance in ovarian cancer.

Epithelial ovarian cancer (EOC) is treated in the first-line setting with combined platinum and taxane chemotherapy, often followed by a maintenance poly (ADP-ribose) polymerase inhibitor (PARPi). Responses to first-line treatment are frequent. For many patients, however, responses are suboptimal or short-lived. Over the last several years, multiple new classes of agents targeting DNA damage response (DDR) mechanisms have advanced through clinical development. In this review, we explore the preclinical rationale for the use of ATR inhibitors, CHK1 inhibitors, and WEE1 inhibitors, emphasizing their application to chemotherapy-resistant and PARPi-resistant ovarian cancer. We also present an overview of the clinical development of the leading drugs in each of these classes, emphasizing the rationale for monotherapy and combination therapy approaches.

Systematic identification of anticancer drug targets reveals a nucleus-to-mitochondria ROS-sensing pathway.

Multiple anticancer drugs have been proposed to cause cell death, in part, by increasing the steady-state levels of cellular reactive oxygen species (ROS). However, for most of these drugs, exactly how the resultant ROS function and are sensed is poorly understood. It remains unclear which proteins the ROS modify and their roles in drug sensitivity/resistance. To answer these questions, we examined 11 anticancer drugs with an integrated proteogenomic approach identifying not only many unique targets but also shared ones-including ribosomal components, suggesting common mechanisms by which drugs regulate translation. We focus on CHK1 that we find is a nuclear H2O2 sensor that launches a cellular program to dampen ROS. CHK1 phosphorylates the mitochondrial DNA-binding protein SSBP1 to prevent its mitochondrial localization, which in turn decreases nuclear H2O2. Our results reveal a druggable nucleus-to-mitochondria ROS-sensing pathway-required to resolve nuclear H2O2 accumulation and mediate resistance to platinum-based agents in ovarian cancers.

Graft Failure after Uterus Transplantation in 16 Recipients: A Review.

Uterus transplantation (UTx) is now an alternative to surrogacy and adoption for women with uterine factor infertility to have children; however, there are still unresolved clinical and technical issues. One of these is that the graft failure rate after transplantation is somewhat higher than that of other life-saving organ transplants, which is a critical concern. Herein, we summarize the details of 16 graft failures after UTx with living or deceased donors using the published literature in order to learn from these negative outcomes. To date, the main causes of graft failure are vascular factors (arterial and/or venous thrombosis, atherosclerosis, and poor perfusion). Many recipients with thrombosis develop graft failure within one month of surgery. Therefore, it is necessary to devise a safe and stable surgical technique with higher success rates for further development in the UTx field.

Characteristics and clinicopathological features of patients with ovarian metastasis of endometrial cancer: a retrospective study.

There are no criteria for patient selection for ovarian-preserving surgery for endometrial cancer (EC). In this study, intraoperative findings of ovarian swelling (OvS) and the clinicopathological features of patients with EC with or without ovarian metastasis were analysed to identify risk factors for ovarian metastasis. Patients who underwent surgery for EC between 2012 and 2019 at our hospital were enrolled. In univariate analysis, all features were significantly higher in metastasis(+) cases. In multivariate analysis, lymphatic space invasion (LSI), cervical stromal involvement (CSI), peritoneal dissemination, and OvS were significant risk factors. In univariate analysis in stage I and II cases classified without adnexal pathological factors, type 2 histologic type, LSI, CSI, and OvS were significantly higher in metastasis(+) cases. LSI, CSI, and OvS were significant risk factors in multivariate analysis. Patients with type 1 histologic type EC without myometrial invasion ≥1/2, CSI and extrauterine lesions are appropriate for ovarian preservation. IMPACT STATEMENTWhat is already known on this subject? The number of premenopausal patients with endometrial cancer (EC) is increasing. Bilateral oophorectomy for EC results in surgical primary ovarian insufficiency, and thus, surgery with ovarian preservation has been examined. However, there are few reports on risk factors for ovarian metastasis of EC and no established criteria for patient background or pathological factors to determine suitability for ovarian preservation surgery.What do the results of this study add? In univariate analysis, all pathological findings suggestive of disease progression were more frequent in cases with ovarian metastases. In multivariate analysis, lymphatic space invasion (LSI), cervical stromal involvement (CSI), peritoneal dissemination, and ovarian swelling (OvS) were identified as significant risk factors for ovarian metastasis. In an analysis of stage I and II cases classified without adnexal pathological factors, type 2 histologic type, LSI, CSI, and OvS were significantly more common in cases with ovarian metastasis, and LSI, CSI, and OvS emerged as significant risk factors for ovarian metastasis in multivariate analysis.What are the implications of these findings for clinical practice and/or further research? Patients with type 1 histologic type EC without depth of myometrial invasion ≥1/2, CSI, or extrauterine lesions may be appropriate cases for ovarian preservation.

Keio Uterus Transplantation Research: From Basic Research toward Future Clinical Application.

Uterus transplantation (UTx) is now a potential option to allow women with uterine factor infertility to give birth. However, UTx is still at an experimental stage, and basic animal studies, including in non-human primates, are needed for the accumulation of data prior to clinical application. Considering that UTx may provide new hope to Japanese women, we launched UTx research in 2009 and have since accumulated a large archive of results in the UTx research field. Furthermore, we have carried out various activities aimed at the implementation of clinical applications of UTx in Japan while clarifying the ethical and social issues involved. Currently, the clinical application of UTx in Japan is just around the corner, and it is expected that UTx research will develop further in the future. Herein, we summarize our basic experiences using non-human primates and our activities with the goal of future clinical applications.

Massive Hemorrhage Due to Cervical Endometriotic Cyst Rupture: Two Case Reports and a Literature Review.

BACKGROUND Endometriosis is defined as the growth of ectopic endometrial tissue beyond the uterine cavity, and endometriosis on the uterine cervix is a rare variant. Although asymptomatic patients with cervical endometriosis or those with minor symptoms are treated conservatively, there are reports of life-threatening hemorrhage due to cervical endometriosis. Here, we report 2 cases of massive genital bleeding caused by cervical endometriotic cysts and we performed a literature review. CASE REPORT Case 1: A 32-year-old woman presented to our hospital due to massive genital bleeding on her 11th day of menstruation. An arterial hemorrhage in a cervical endometriotic cyst was suspected. As pressure hemostasis proved difficult, urgent uterine artery embolization (UAE) by interventional radiology was performed. Angiography during the UAE showed extravascular leakage from the branch of the left uterine artery. After embolization, hemostasis was achieved. No further genital bleeding was observed, and transvaginal ultrasound showed the cyst has continued to shrink for 9 months after the UAE with sequential dienogest, a progesterone receptor agonist, treatment. Case 2: A 43-year-old woman presented to our hospital with increasing massive genital bleeding after completing a 12-day course of 0.5 mg of norgestrel and 0.05 mg of ethinyl estradiol as a treatment for irregular intermenstrual bleeding. We suspected cervical endometriotic cyst rupture on imaging and performed an urgent laparoscopic total hysterectomy. In the excised uterine specimen, a cystic lesion that contained old, blood-like fluid was macroscopically observed in the cervix and was diagnosed pathologically as endometriosis. CONCLUSIONS Cervical endometriotic cyst rupture is rare; however, it should be kept in mind as a differential diagnosis when treating massive genital bleeding because urgent intervention is sometimes required to control the bleeding.

Hysteroscopic treatment assisted by photodynamic diagnosis for atypical polypoid adenomyoma: A report of two cases.

Atypical polypoid adenomyoma (APA) is an intrauterine tumor for which hysteroscopic tumor resection allows for fertility preservation. Complete resection is important because of the high recurrence rate of APA, but is difficult due to the lack of characteristic hysteroscopic findings. We previously reported a case in which photodynamic diagnosis (PDD) was useful for detection of APA. Here, we report two additional cases of APA treated by hysteroscopic resection with PDD. The procedure was approved by the ethical committee. Case 1: A 35-year-old female who underwent hysteroscopic surgery for a submucosal tumor suspected to be APA with hypermenorrhea. Case 2: A 37-year-old female in whom hysteroscopic surgery was performed for a residual APA lesion after hormone therapy. In Case 1, PDD identified the tumor borders and this enabled as complete resection as possible. In Case 2, lesions could not be identified clearly under white light, but some areas were PDD-positive and were excised. Among 19 specimens from these two cases and the previously reported case, all PDD-positive specimens were pathologically diagnosed as APA. The sensitivity and specificity of PDD for APA were 76.9% and 100%, respectively. These results suggest that PDD can contribute to identification of APA.

Meningitis caused by Listeria monocytogenes in a locally advanced cervical cancer patient with pyometra: A case report.

Locally advanced cervical cancer occasionally induces pyometra, but there have been no reports of meningitis where pyometra is the cause of infection. Here, we report a case of Listeria monocytogenes meningitis related to pyometra during concurrent chemoradiotherapy (CCRT) in a cervical cancer patient. The patient, a 77-year-old woman, was diagnosed with Stage IIB (FIGO 2018) cervical adenocarcinoma, and CCRT was initiated. Pyometra was exacerbated during CCRT, and after her first brachytherapy, she presented at our hospital with fever and decreased consciousness level. After admission to the Intensive Care Unit, the patient lost consciousness and experienced frequent seizures; tracheal intubation was required. Whole-body computed tomography revealed pyometra; therefore, transvaginal removal of the abscess was performed. Laboratory tests and vital signs indicated septic shock, and meropenem was administered. L. monocytogenes was detected in the abscess from the uterine cavity and the blood cultures on the third day of hospitalization. A lumbar puncture was performed on the same day to investigate whether the patient had meningitis. A FilmArray meningitis/encephalitis panel test of the spinal fluid revealed L. monocytogenes. After the diagnosis of meningitis with L. monocytogenes, ampicillin and gentamicin were started, and the blood test results gradually improved. Five months after the initial episode, her consciousness recovered, however she still received mechanical ventilatory support. L. monocytogenes infections can occur in patients undergoing chemotherapy, even without the use of steroids or immunosuppressive agents. In cases with pyometra, intrauterine manipulation can increase the risk of severe infection.

Initiatives and achievements of the Japanese Society of Obstetrics and Gynecology, Obstetrics and Gynecology MIRAI Committee 2020.

BACKGROUNDS: In 2013, the total number of obstetrician-gynecologists decreased. The Japanese Society of Obstetrics and Gynecology established the Obstetrics and Gynecology MIRAI Committee in 2015. Within the MIRAI Committee, Japanese Trainees in Obstetrics and Gynecology (JTOG) was established; it was comprised of 20 promising young obstetrician-gynecologists recommended from regions across Japan. The office term is 2 years. OBJECTIVE: The purpose of this report is to learn and inform about the results of MIRAI's activities. METHODS: We surveyed the trends in new obstetrician-gynecologists and also matched each seminar participant with them. RESULT: The number of new memberships has been increasing since the nadir in 2016. In particular, there are over 100 more new physicians specializing in the field in 2020 than there were at the nadir in 2016. It was revealed that approximately 50% of the participants in the summer school specialized in obstetrics and gynecology. Furthermore, approximately 70% of POP2 participants specialized in obstetrics and gynecology, which shows that these two recruitment seminars are extraordinarily effective events that result in an increase in the number of new obstetricians and gynecologists. CONCLUSION: We conclude that the activities of this MIRAI Committee and JTOG have been effective. With the spread of COVID-19 and the inability of obstetrician-gynecologists and students/clinical trainees to perform social distancing, it is currently difficult to hold hands-on seminars. However, we hope that new JTOG members will be able to create a new seminar format.

A survey of Japanese interns to prepare for mandatory clinical training in obstetrics and gynecology.

AIM: Obstetrics and gynecology (Ob/Gyn) training became compulsory for Japanese physician interns from April 2020 to improve medical competence in treating women's diseases. This study aims to understand the Ob/Gyn training needs of postgraduate year 1-2 physicians (interns) and thereby improve training efficiency. METHODS: This study was administered to interns at Ob/Gyn training facilities from December 2019 to February 2020. An original questionnaire was used to evaluate their assessment of training needs. In analyses, interns were categorized according to whether they were willing to major in Ob/Gyn. RESULTS: Of the 1154 participants, 163 (14.1%) would major in Ob/Gyn (Ob/Gyn applicants) and 967 (83.8%) would not (non-Ob/Gyn applicants). At the time of the survey, 634 (54.9%) had rotated in Ob/Gyn, 253 (21.9%) planned to rotate, and 267 (23.1%) chose not to rotate. The two most favorable training experiences were "experience in surgical procedures" (81/141, 57.4%) and "wide treatment areas covered by Ob/Gyn" (78/141, 55.3%) among the Ob/Gyn applicants, and "specificity of women's treatment" (308/488, 63.1%) among the non-Ob/Gyn applicants. CONCLUSIONS: Ob/Gyn applicants and non-Ob/Gyn applicants differed in their assessment of Ob/Gyn rotations. It is crucial to provide medical training based on interns' needs to improve their skills for treating female patients.

Operative and Clinical Outcomes of Minimally Invasive Living-Donor Surgery on Uterus Transplantation: A Literature Review.

BACKGROUND: The surgical approach and choice of drainage veins for uterus transplantation living-donor surgery have been investigated to reduce invasiveness. METHODS: A thorough search of the PubMed database was conducted. The search was not limited by language or date of publication. The data were collected on 13 October 2020. Two reviewers independently assessed each article and determined eligibility for inclusion in the review article. Inclusion criteria were English peer-reviewed articles reporting surgical information or postoperative course, articles regarding animal research on UTx, UTx on deceased donors, or not original articles. RESULTS: Of the 51 operations within 26 articles reviewed, the mean operative time was shortest in the laparoscopic approach, and longest in the robot-assisted approach. The mean blood loss was less in the laparoscopic and robot-assisted approaches than in the open approach. In cases where the uterine veins were not preserved, the mean operative time was shortened by each approach and the mean blood loss decreased with the laparoscopic and robot-assisted approaches. CONCLUSIONS: These procedures may contribute to less invasive living-donor surgery.

Concerns Associated with Uterus Transplantation in Japan.

Uterus transplantation (UTx) has seen increasing global adoption as an alternative for women with uterine factor infertility to achieve pregnancy. However, several medical, ethical, and social issues need to be addressed before UTx can be applied clinically. Since 2009, Japan has amassed a large database of basic research on UTx in non-human primates, but clinical application has not been realized because of conservative attitudes and prudent concerns. Nonetheless, UTx may be viable in Japan after comprehensive resolution of the concerns associated with this medical technology.

First Successful Delivery after Uterus Transplantation in MHC-Defined Cynomolgus Macaques.

Delivery following uterus transplantation (UTx)-an approach for treating uterine factor infertility-has not been reported in nonhuman primate models. Here, six female major histocompatibility complex (MHC)-defined cynomolgus macaques that underwent allogeneic UTx were evaluated. Antithymocyte globulin and rituximab were administered to induce immunosuppression and a triple maintenance regimen was used. Menstruation resumed in all animals with long-term survival, except one, which was euthanized due to infusion associated adverse reaction to antithymocyte globulin. Donor-specific antibodies (DSA) were detected in cases 2, 4, and 5, while humoral rejection occurred in cases 4 and 5. Post-transplant lymphoproliferative disorder (PTLD) developed in cases 2 and 3. Pregnancy was attempted in cases 1, 2, and 3 but was achieved only in case 2, which had haploidentical donor and recipient MHCs. Pregnancy was achieved in case 2 after recovery from graft rejection coincident with DSA and PTLD. A cesarean section was performed at full-term. This is the first report of a successful livebirth following allogeneic UTx in nonhuman primates, although the delivery was achieved via UTx between a pair carrying haploidentical MHCs. Experimental data from nonhuman primates may provide important scientific knowledge needed to resolve unsolved clinical issues in UTx.

Experimental techniques for the development of a uterus transplantation model in cynomolgus macaques.

Uterus transplantation (UTx) is now a treatment for women with uterine factor infertility to have a child. However, UTx is still largely at the experimental stage, and many medical issues remain unsolved. Therefore, adequate studies in large animals including non-human primates are required for validation of these issues. UTx research, especially in non-human primates, can provide important information for its full establishment in humans due to the anatomical and physiological similarities between the two. We accumulated data from UTx studies using cynomolgus macaques since 2009 and established autologous and allogeneic UTx models which led to deliveries after performing the procedure. In this paper, we summarized key points to develop UTx models in cynomolgus macaques based on our experience. UTx models in non-human primates can surely contribute new and beneficial knowledge in this field and can be useful for the further development of UTx in humans.

Clinical features of irreversible rejection after allogeneic uterus transplantation in cynomolgus macaques.

Uterus transplantation (UTx) is a potential option for women with uterine factor infertility to have a child. The clinical features indicating irreversible rejection of the uterus are unknown. In our experimental series of allogeneic UTx in cynomolgus macaques, six female macaques were retrospectively examined, which were unresponsive to treatment with immunosuppressants (i.e. irreversible rejection). Clinical features including general condition, hematology, uterine size, indocyanine green (ICG) fluorescence imaging by laparotomy, and histopathological findings of the removed uterus were evaluated. In all cases, general condition was good at the time of diagnosis of irreversible rejection and thereafter. Laboratory evaluation showed temporary increases in white blood cells, lactate dehydrogenase and C-reactive protein, then these levels tended to decrease gradually. In transabdominal ultrasonography, the uterus showed time-dependent shrinkage after transient swelling at the time of diagnosis of irreversible rejection. In laparotomy, a whitish transplanted uterus was observed and enhancement of the transplanted uterus was absent in ICG fluorescence imaging. Histopathological findings in each removed uterus showed hyalinized fibrosis, endometrial deficit, lymphocytic infiltration and vasculitis. These findings suggest that uterine transplantation rejection is not fatal, in contrast to rejection of life-supporting organs. Since the transplanted uterus with irreversible rejection atrophies naturally, hysterectomy may be unnecessary.

Evaluation of safety and diagnostic performance for flexible hysteroscopy in 1591 outpatient cases.

BACKGROUND: To date, only few large studies are available concerning the safety and diagnostic concordance rates of outpatient flexible hysteroscopy. In our institution, outpatient hysteroscopy has been routinely and educationally applied Kosuke Tsuji to intrauterine lesions; thus, we retrospectively investigated the institution's outpatient flexible hysteroscopy cases. METHODS: A total of 1591 cases of outpatient flexible hysteroscopy conducted at our institution in 2012-2016 were retrospectively analyzed in terms of their clinical background, complications and diagnostic concordance rates. RESULTS: A total of 1591 cases included 546 cases of benign tumors (317 endometrial polyps, 168 myomas and 61 endometrial hyperplasia), 361 cases of atypical endometrial hyperplasia, 571 cases of endometrial cancers and 113 cases of other diagnoses. No major complications, including uterine perforation, occurred. However, one patient (0.06%) was diagnosed with septic shock caused by intrauterine infection that required prolonged immunosuppressive drug administration. Meanwhile, 335 patients diagnosed with benign tumors through outpatient flexible hysteroscopy underwent operation, and the diagnostic concordance rate was 74.6% (250 cases). However, this rate included 14 cases (4.2%) diagnosed with malignant tumors postoperatively. In preoperative endometrial cancer cases, the sensitivity and specificity for cervical invasion diagnosis were 39.4 and 90.8%, respectively. In addition, only one patient manifested positive ascites cytology intraoperatively, possibly caused by outpatient hysteroscopy. CONCLUSIONS: Outpatient flexible hysteroscopy is highly safe, with a slight negligible effect on ascites cytology. However, the diagnosis should be determined by multidisciplinary approaches, as hysteroscopy alone can miss malignancy.

Hysteroscopic Photodynamic Diagnosis Using 5-Aminolevulinic Acid: A High-Sensitivity Diagnostic Method for Uterine Endometrial Malignant Diseases.

STUDY OBJECTIVE: To examine the diagnostic accuracy of hysteroscopic photodynamic diagnosis (PDD) using 5-aminolevulinic acid (5ALA) in patients with endometrial cancer and premalignant atypical endometrial hyperplasia. DESIGN: A single-center, open-label, exploratory intervention study. SETTING: University Hospital in Japan. PATIENTS: Thirty-four patients who underwent hysteroscopic resection in the Department of Obstetrics and Gynecology at Keio University Hospital. INTERVENTIONS: Patients were given 5ALA orally approximately 3 hours before surgery and underwent observation of the uterine cavity and endometrial biopsy using 5ALA-PDD during hysteroscopic resection. Specimens were diagnosed histopathologically and the diagnostic sensitivity and specificity of hysteroscopic 5ALA-PDD for malignancy in the uterine cavity was determined. Red (R), blue (B), and green (G) intensity values were determined from PDD images, and the relationships of histopathological diagnosis with these values were used to develop a model for objective diagnosis of uterine malignancy. MEASUREMENTS AND MAIN RESULTS: Three patients were excluded from the study because of failure of the endoscope system. A total of 113 specimens were collected endoscopically. The sensitivity and specificity of 5ALA-PDD for diagnosis of malignancy in the uterine cavity were 93.8% and 51.9%, respectively. The R/B ratio in imaging analysis was highest in malignant lesions, followed by benign lesions and normal uterine tissue, with significant differences among these groups (p <.05). The R/B and G/B ratios were used in a formula for prediction of malignancy based on logistic regression and the area under the receiver operating characteristic curve for this formula was 0.838. At a formula cutoff value of 0.220, the sensitivity and specificity for diagnosis of malignant disease were 90.6% and 65.4%, respectively. CONCLUSION: To our knowledge, this is the first study of the diagnostic accuracy of 5ALA-PDD for malignancies in the uterine cavity. Hysteroscopic 5ALA-PDD had higher sensitivity and identifiability of lesions. These findings suggest that hysteroscopic 5ALA-PDD may be useful for diagnosis of minute lesions.