ASCT2 regulates glutamine uptake and cell growth in endometrial carcinoma

Glutamine commonly becomes a conditionally essential amino acid in cancer. Glutamine is supplied to the cell by transporters such as ASCT2 (SLC1A5), which is frequently upregulated in multiple cancers. Here we investigated the expression of ASCT2 in endometrial carcinoma, and evaluated the contribution of ASCT2 to glutamine uptake and endometrial cancer cell growth. Analysis of human gene expression data showed that ASCT2 was significantly upregulated in both endometrioid and serous subtypes of endometrial carcinoma, compared to normal, age-matched endometrium. Furthermore, immunohistochemical staining of primary human endometrioid adenocarcinomas showed that tumours stain positive for ASCT2 in either a uniform or mosaic expression pattern, while normal adjacent glands appeared predominantly negative for ASCT2 staining. Chemical inhibition of glutamine transport by benzylserine or GPNA led to a significant decrease in endometrial cancer cell growth and spheroid cross-sectional area. ASCT2 knockdown recapitulated the decrease of cell growth and spheroid cross-sectional area in HEC1A cells, suggesting a reliance on ASCT2-mediated glutamine uptake. ASCT2 knockdown in Ishikawa cells led to lower glutamine uptake and cell growth, but did not affect spheroid area. Ishikawa cells express higher levels of the glutamine transporter SNAT1 compared to HEC1A cells, suggesting these cells may rely on both ASCT2 and SNAT1 for glutamine uptake. Since SNAT1 is also significantly upregulated in the endometrioid and serous subtypes, these data indicate that ASCT2 and SNAT1 could be used as markers of malignancy, and/or potential therapeutic targets in patients with endometrial carcinoma

CTCF genetic alterations in endometrial carcinoma are pro-tumorigenic

CTCF is a haploinsufficient tumour suppressor gene with diverse normal functions in genome structure and gene regulation. However the mechanism by which CTCF haploinsufficiency contributes to cancer development is not well understood. CTCF is frequently mutated in endometrial cancer. Here we show that most CTCF mutations effectively result in CTCF haploinsufficiency through nonsense-mediated decay of mutant transcripts, or loss-of-function missense mutation. Conversely, we identified a recurrent CTCF mutation K365T, which alters a DNA binding residue, and acts as a gain-of-function mutation enhancing cell survival. CTCF genetic deletion occurs predominantly in poor prognosis serous subtype tumours, and this genetic deletion is associated with poor overall survival. In addition, we have shown that CTCF haploinsufficiency also occurs in poor prognosis endometrial clear cell carcinomas and has some association with endometrial cancer relapse and metastasis. Using shRNA targeting CTCF to recapitulate CTCF haploinsufficiency, we have identified a novel role for CTCF in the regulation of cellular polarity of endometrial glandular epithelium. Overall, we have identified two novel pro-tumorigenic roles (promoting cell survival and altering cell polarity) for genetic alterations of CTCF in endometrial cancer

Metastatic ovarian disease following surgical management of grade 1 endometrial endometrioid adenocarcinoma confined to the endometrium : a case report and review of the literature

Endometrial endometrioid type cancer is a common gynaecological cancer for which the standard surgical management includes hysterectomy and bilateral salpingo-oophorectomy. The value of oophorectomy is to remove occult ovarian disease. It is estimated that 5 % of low grade endometrioid adenocarcinoma will have concurrent ovarian involvement (3 % synchronous tumours, 2 % ovarian metastases), of which only 1 % will be microscopic. Ovarian preservation at the time of surgery can be considered, especially in early-stage disease or premenopausal women. We describe a case of metastatic ovarian disease following surgical management of grade 1 endometrial endometrioid adenocarcinoma confined to the endometrium (FIGO stage 1a), in a postmenopausal woman who declined primary oophorectomy. This case was without genetic predisposition and recurred 12 months after initial surgical treatment. This case is incongruent with what has previously been understood for FIGO stage 1a endometrial endometrioid adenocarcinoma and highlights that even disease seemingly confined to the endometrium can metastasise microscopically to the ovaries

Clinical and molecular classification of vulvar squamous pre-cancers

Vulvar intraepithelial neoplasia (VIN) is a precursor to vulvar squamous cell carcinoma and is defined histopathologically by the presence of atypia. VIN has been classified into two types: usual vulvar intraepithelial neoplasia (uVIN), which is also referred to as a vulvar high-grade squamous intra-epithelial lesion (HSIL), and differentiated VIN (dVIN). The former is associated with chronic infection by sub-types of the human papilloma virus (HPV), whereas dVIN is HPV-independent and frequently associated with lichen sclerosus. The distinction is important because dVIN has a greater risk of, and more rapid transit to, vulvar squamous cell carcinoma. Furthermore, dVIN-associated vulvar cancers have an increased risk of recurrence and higher mortality than those arising from HSIL. Molecular characterization of vulvar squamous cell carcinoma precursors using next-generation sequencing is a relatively novel, but rapidly advancing field. This review appraises recent studies that have investigated the risks of progression to vulvar malignancy associated with HSIL and dVIN, the prognosis of HPV-dependent and HPV-independent vulvar squamous cell carcinomas, and conducted next generation sequencing mutation analyses to elucidate the genomic profiles underlying VIN. These studies suggest that HSIL and dVIN are characterized by different underlying molecular alterations that may have important implications for treatment and follow-up of women diagnosed with vulvar squamous cell cancer

A novel cause of postmenopausal bleeding in an immunosuppressed patient

Malakoplakia is a rare histiocytic disease first described in 1902 by Michaelis and Gutmann. It is associated with host immunocompromise including chronic inflammatory conditions, infectious conditions or malnutrition. Here, we report the case of uterine malakoplakia as a rare cause of postmenopausal bleeding in an immunocompromised patient

Intraoperative frozen section of ovarian tumors : a 6-year review of performance and potential pitfalls in an Australian Tertiary Referral Center

Objectives Intraoperative frozen section (IFS) offers a rapid test to guide the extent of surgery, which is essential for optimal treatment of ovarian cancer. This study evaluated the diagnostic performance and influence of IFS in the surgical management of ovarian tumors. Methods A retrospective review was conducted of IFS of adnexal lesions from 2008 to 2013, with diagnoses classified as benign, borderline, or malignant. The diagnostic performance of IFS was calculated, with a focus on primary epithelial tumors. In discordant cases, it was determined whether the results of the IFS influenced the nature of the primary surgery. Results There were 277 consecutive cases over the study period. The overall sensitivity for diagnosing malignant disease was 75.9% and the specificity was 100%. With a benign IFS result, there was a 6.25% (9/144) chance that the final diagnosis would be malignant, and a 7.6% (11/144) chance that the final diagnosis would be borderline, resulting in the potential for understaging. The predictive values for benign, borderline, and malignant IFS results were 86.1%, 66.6%, and 100%, respectively. For a borderline IFS result, there was a 33.3% chance that the final diagnosis would be malignant disease, and this was higher in older patients (53.3%). There were no instances of overdiagnosis in this series. Of 37 cases underdiagnosed, 19 received incomplete primary staging surgery guided by the IFS, and most of these were mucinous tumors. Conclusions Intraoperative frozen section is most valuable for its high specificity in diagnosing malignancy. It should be interpreted with caution in borderline tumors, particularly in older patients and in mucinous tumors. Overdiagnosis did not occur in this series; however, in younger patients, the limitations of IFS must be considered before surgery that would result in loss of fertility

The lymphatic system in endometriosis : a pilot study of endometrial-like cells and immune cell populations in lymph nodes associated with deep infiltrating bowel lesions

In endometriosis, the lymphatic and immune systems are implicated in disease establishment and progression. The objective of this pilot study was to examine endometrial-like, and for the first time, immune cell populations in lymph nodes associated with deep infiltrating endometriosis (DIE) bowel lesions. Premenopausal women undergoing excision of endometriosis and/or hysterectomy were included. DIE bowel lesion-associated (n = 10) and other pelvic (n = 15) lymph nodes were studied. Samples were immunohistochemically stained for endometrial-like cells (CD10), T cells (CD3, CD4, CD8, and FoxP3), dendritic cells (DC; DC-Lamp and DC-Sign), B cells (CD20, CD79 and plasma), macrophages (CD68), and natural killer cells (NK; CD57). Cell abundance (percentage positive area) and antigen expression (optical density; OD) were quantified. Endometrial-like cells and each immune cell population were present in all studied nodes. The DIE bowel lesion-associated nodes showed features of immune activation, with T cell proliferation (CD3+ area p = 0.007, CD4+ area p = 0.015 compared with other pelvic nodes); and a mixture of helper and regulatory T cells, B cells, DCs, macrophages, and plasma cells present in the paracortex. In DIE bowel lesion-associated compared with other pelvic nodes, CD10+ endometrial-like cells were reduced (percentage positive area p < 0.001, OD p = 0.004). This study provides new insight into lymphatic and immune system involvement in advanced endometriosis. In particular, we have shown evidence of immune activation in DIE lesion-associated nodes. This was despite lower endometrial-like cell numbers compared with other pelvic nodes. The observations contribute to a developing understanding of the local immune response to advanced disease

Follow-up after treatment of high-grade cervical dysplasia : the utility of six-month colposcopy and cytology and routine 12-month colposcopy

Background: Australian Cervical Screening Program guidelines no longer recommend colposcopy and cytology at six months following treatment of cervical intraepithelial neoplasia (CIN2/3) and a co-test of cure can be performed at 12 months without colposcopy. Aims: To determine the usefulness of six-month colposcopy and cytology and routine colposcopy with co-testing at 12 months in detecting persistent or recurrent disease in patients treated for CIN2/3. Materials and Methods: We conducted a review of all patients with histologically proven CIN2/3 who underwent a cervical excisional procedure between March 2012 and March 2017 in one specialised centre. Results: We examined 1215 cases and 750 remained after exclusions for analysis. At six months (722 cases, 96.2%) seven of 42 (16.7%) patients with high-grade cytology had a high-grade colposcopy and 24 of 42 (57.1%) had a normal colposcopy. Persistent CIN2/3 was diagnosed in 12 cases (1.7%) and only 1/3 had a high-grade colposcopy. Cytology was more useful than colposcopy in detecting persistent disease. At 12 months (638 cases, 85%) routine colposcopy at the time of co-testing had a high false positive rate with all high-grade changes negative on biopsy and co-test. Recurrent CIN2/3 was diagnosed in five cases, and four had normal colposcopy at co-testing. Conclusions: There may be a delay in detection of persistent/recurrent CIN2/3 in a small number of cases without six-month colposcopy and cytology; however, it is not likely to negatively impact overall clinical outcome. Co-testing at 12 months following treatment of CIN2/3 without colposcopy is safe and routine colposcopy at collection of the co-test can be omitted

The impact of primary human papillomavirus screening on negative loop excision histology following biopsy-proven high-grade cervical intra-epithelial lesions : a review from a large tertiary colposcopy unit

Background: The renewed National Cervical Screening Program incorporating primary human papillomavirus (HPV) screening was implemented in Australia in December 2017. In a previous study conducted in the UK, primary HPV screening was found to be associated with a 25% reduction in the incidence of negative histology following loop electrosurgery excision procedure (LEEP). Aim: To examine the change in incidence and associated risk factors for a negative LEEP with introduction of primary HPV screening. Materials and Methods: A retrospective review of the records of all patients undergoing a LEEP excision for biopsy-proven high-grade cervical intra-epithelial lesions between 1 January 2014 and 30 June 2019 in a specialised centre. Results: There were 1123 patients who underwent a LEEP included in the analysis. The incidence of a negative LEEP specimen was 7.5% (59/784) and 5.3% (18/339) in the pre- and post-HPV screening cohort. More patients in the post-HPV screening group had low-grade cytology on referral (P < 0.001), smaller cervical lesions on colposcopy (P = 0.012) and longer biopsy to treatment interval (P = 0.020). Primary HPV screening was associated with a significant reduction in the incidence of a negative LEEP specimen in a propensity matched cohort (11.2% to 5.1%, P = 0.006) and a 41% (P = 0.045) decreased relative risk of a negative LEEP on multivariate analysis. Conclusions: Primary HPV screening results in a lower incidence of negative LEEP histology, despite a longer biopsy to treatment wait time and higher proportion of low-grade cytology at triage

Fluorescent in situ hybridization in surgical pathology practice

There have been rapid and significant advances in diagnostic and predictive molecular techniques in recent years with profound impact on patient care. In situ hybridization (ISH) studies have become well entrenched in surgical pathology practice and their role in the evaluation of HER2 in breast carcinoma and their diagnostic utility in soft tissue pathology are well known. Fluorescent ISH is being increasingly used in other sites such as the head and neck and the gynecologic tract. Like most tests in surgical pathology, ISH studies require good quality tissue, correlation with clinical and histopathologic findings, and adherence to guidelines for optimal assay performance and interpretation. Although ISH studies are largely performed in tertiary centers, the tissue is often processed by a variety of laboratories and the referring pathologists are required to discuss the need, relevance, and significance of these tests and the results with their clinical colleagues. Here we review the predictive and diagnostic utility of fluorescent ISH studies in a variety of organ systems, the preanalytical factors that may affect the results, and the pitfalls in the interpretation that all practicing surgical pathologists should be aware of