Concise Reporting of Benign Endometrial Biopsies is an Acceptable Alternative to Descriptive Reporting

In the United Kingdom, endometrial biopsy reports traditionally consist of a morphologic description followed by a conclusion. Recently published consensus guidelines for reporting benign endometrial biopsies advocate the use of standardized terminology. In this project we aimed to assess the acceptability and benefits of this simplified "diagnosis only" format for reporting non-neoplastic endometrial biopsies. Two consultants reported consecutive endometrial biopsies using 1 of 3 possible formats: (i) diagnosis only, (ii) diagnosis plus an accompanying comment, and (iii) the traditional descriptive format. Service users were asked to provide feedback on this approach via an anonymized online survey. The reproducibility of this system was assessed on a set of 53 endometrial biopsies among consultants and senior histopathology trainees. Of 370 consecutive benign endometrial biopsies, 245 (66%) were reported as diagnosis only, 101 (27%) as diagnosis plus a brief comment, and 24 (7%) as diagnosis following a morphologic description. Of the 43 survey respondents (28 gynecologists, 11 pathologists, and 4 clinical nurse specialists), 40 (93%) preferred a diagnosis only, with 3 (7%) being against/uncertain about a diagnosis only report. Among 3 histopathology consultants and 4 senior trainees there was majority agreement on the reporting format in 53/53 (100%) and 52/53 (98%) biopsies. In summary, we found that reporting benign specimens within standardized, well-understood diagnostic categories is an acceptable alternative to traditional descriptive reporting, with the latter reserved for the minority of cases that do not fit into specific categories. This revised approach has the potential to improve reporting uniformity and reproducibility.

3D Functional Genomics Screens Identify CREBBP as a Targetable Driver in Aggressive Triple-Negative Breast Cancer

Triple-negative breast cancers (TNBC) are resistant to standard-of-care chemotherapy and lack known targetable driver gene alterations. Identification of novel drivers could aid the discovery of new treatment strategies for this hard-to-treat patient population, yet studies using high-throughput and accurate models to define the functions of driver genes in TNBC to date have been limited. Here, we employed unbiased functional genomics screening of the 200 most frequently mutated genes in breast cancer, using spheroid cultures to model in vivo-like conditions, and identified the histone acetyltransferase CREBBP as a novel tumor suppressor in TNBC. CREBBP protein expression in patient tumor samples was absent in 8% of TNBCs and at a high frequency in other tumors, including squamous lung cancer, where CREBBP-inactivating mutations are common. In TNBC, CREBBP alterations were associated with higher genomic heterogeneity and poorer patient survival and resulted in upregulation and dependency on a FOXM1 proliferative program. Targeting FOXM1-driven proliferation indirectly with clinical CDK4/6 inhibitors (CDK4/6i) selectively impaired growth in spheroids, cell line xenografts, and patient-derived models from multiple tumor types with CREBBP mutations or loss of protein expression. In conclusion, we have identified CREBBP as a novel driver in aggressive TNBC and identified an associated genetic vulnerability in tumor cells with alterations in CREBBP and provide a preclinical rationale for assessing CREBBP alterations as a biomarker of CDK4/6i response in a new patient population. SIGNIFICANCE: This study demonstrates that CREBBP genomic alterations drive aggressive TNBC, lung cancer, and lymphomas and may be selectively treated with clinical CDK4/6 inhibitors.

Homologous recombination DNA repair deficiency and PARP inhibition activity in primary triple negative breast cancer

Triple negative breast cancer (TNBC) encompasses molecularly different subgroups, with a subgroup harboring evidence of defective homologous recombination (HR) DNA repair. Here, within a phase 2 window clinical trial, RIO trial (EudraCT 2014-003319-12), we investigate the activity of PARP inhibitors in 43 patients with untreated TNBC. The primary end point, decreased Ki67, occured in 12% of TNBC. In secondary end point analyses, HR deficiency was identified in 69% of TNBC with the mutational-signature-based HRDetect assay. Cancers with HRDetect mutational signatures of HR deficiency had a functional defect in HR, assessed by impaired RAD51 foci formation on end of treatment biopsy. Following rucaparib treatment there was no association of Ki67 change with HR deficiency. In contrast, early circulating tumor DNA dynamics identified activity of rucaparib, with end of treatment ctDNA levels suppressed by rucaparib in mutation-signature HR-deficient cancers. In ad hoc analysis, rucaparib induced expression of interferon response genes in HR-deficient cancers. The majority of TNBCs have a defect in DNA repair, identifiable by mutational signature analysis, that may be targetable with PARP inhibitors.

Assessment of Molecular Relapse Detection in Early-Stage Breast Cancer

Importance

Current treatment cures most cases of early-stage, primary breast cancer. However, better techniques are required to identify which patients are at risk of relapse.

Objective

To assess the clinical validity of molecular relapse detection with circulating tumor DNA (ctDNA) analysis in early-stage breast cancer.

Design, Setting, and Participants

This prospective, multicenter, sample collection, validation study conducted at 5 United Kingdom medical centers from November 24, 2011, to October 18, 2016, assessed patients with early-stage breast cancer irrespective of hormone receptor and ERBB2 (formerly HER2 or HER2/neu) status who were receiving neoadjuvant chemotherapy followed by surgery or surgery before adjuvant chemotherapy. The study recruited 170 women, with mutations identified in 101 patients forming the main cohort. Secondary analyses were conducted on a combined cohort of 144 patients, including 43 patients previously analyzed in a proof of principle study.

Interventions

Primary tumor was sequenced to identify somatic mutations, and personalized tumor-specific digital polymerase chain reaction assays were used to monitor these mutations in serial plasma samples taken every 3 months for the first year of follow-up and subsequently every 6 months.

Main Outcomes and Measures

The primary end point was relapse-free survival analyzed with Cox proportional hazards regression models.

Results

In the main cohort of 101 female patients (mean [SD] age, 54 [11] years) with a median follow-up of 35.5 months (interquartile range, 27.9-43.0 months), detection of ctDNA during follow-up was associated with relapse (hazard ratio, 25.2; 95% CI, 6.7-95.6; P < .001). Detection of ctDNA at diagnosis, before any treatment, was also associated with relapse-free survival (hazard ratio, 5.8; 95% CI, 1.2-27.1; P = .01). In the combined cohort, ctDNA detection had a median lead time of 10.7 months (95% CI, 8.1-19.1 months) compared with clinical relapse and was associated with relapse in all breast cancer subtypes. Distant extracranial metastatic relapse was detected by ctDNA in 22 of 23 patients (96%). Brain-only metastasis was less commonly detected by ctDNA (1 of 6 patients [17%]), suggesting relapse sites less readily detectable by ctDNA analysis.

Conclusions and Relevance

The findings suggest that detection of ctDNA during follow-up is associated with a high risk of future relapse of early-stage breast cancer. Prospective studies are needed to assess the potential of molecular relapse detection to guide adjuvant therapy.

Abstract P4-01-01: Molecular residual disease detection with circulating tumor DNA analysis predicts relapse in patients with early stage breast cancer

Background. Detection of circulating tumor DNA (ctDNA) after treatment of early stage breast cancer may identify molecular residual disease. In a prior proof-of-principle study we demonstrated that detection of ctDNA predicted relapse with high accuracy (Garcia-Murillas et al Science Trans Med 2015). We conducted an independent, prospective, multi-centre validation study.

Methods. In this validation study, a cohort of 170 early stage breast cancer patients were recruited from five hospitals into two prospective sample collection studies. Patients were scheduled to receive standard chemotherapy, surgery +/- radiotherapy, adjuvant endocrine therapy and HER2 antibodies as appropriate. Plasma samples were collected for ctDNA analysis at baseline, post-surgery, three monthly for the first year of follow-up, and six monthly thereafter and shipped to a central lab for processing. Using previously established criteria, tumor was sequenced to identify somatic mutations that were tracked by digital PCR in DNA extracted from 4mls of plasma at all available time points. Buffy coat DNA was analysed at all time-points to control for clonal haematopoesis of indeterminate potential (CHIP) detection. The primary endpoint was to compare invasive disease free survival between patients with and without detection of ctDNA after treatment. A combined analysis of this validation study, and the prior proof-of-principle study, was also conducted to analyse secondary endpoints.

Results. After tumor sequencing, 101 patients from the validation study had at least one mutation to track. At median 35.5 months follow-up, ctDNA was detected in plasma of 15.8% (16/101) patients. Detection of ctDNA strongly predicted relapse, hazard ratio 24.5 (95% CI 6.5 to 93.2, P&lt;0.001 time-dependent Cox model), and was predictive of relapse in all tumor subtypes.

In the combined analysis (N=144), lead-time between ctDNA detection and relapse was 10.7 months (95% CI 7.7-17.0). Six patients had a clinical relapse that was not detected by ctDNA prior to relapse. These patients had a distinct pattern of oligo-metastatic relapse, 3 patients with brain-only metastases (P=0.0068), 1 ovarian oligo-metastasis and 2 local disease recurrence. The level of ctDNA in baseline plasma, prior to treatment, was associated with tumor subtype, highest in triple negative breast cancer (P=0.0036).

Conclusion. Detection of ctDNA after treatment is associated with a high risk of future relapse in early-stage breast cancer. Prospective studies are required to assess the potential of molecular residual disease detection to guide adjuvant therapy.

Citation Format: Turner N, Garcia-Murillas I, Chopra N, Comino-Mendez I, Beaney M, Tovey H, Cutts R, Swift C, Kriplani D, Afentakis M, Hrebien S, Walsh G, Johnston S, Ring A, Russell S, Evans A, Skene A, Wheatley D, Dowsett M, Smith I. Molecular residual disease detection with circulating tumor DNA analysis predicts relapse in patients with early stage breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-01-01.

Optimised ARID1A immunohistochemistry is an accurate predictor of ARID1A mutational status in gynaecological cancers

ARID1A is a tumour suppressor gene that is frequently mutated in clear cell and endometrioid carcinomas of the ovary and endometrium and is an important clinical biomarker for novel treatment approaches for patients with ARID1A defects. However, the accuracy of ARID1A immunohistochemistry (IHC) as a surrogate for mutation status has not fully been established for patient stratification in clinical trials. Here we tested whether ARID1A IHC could reliably predict ARID1A mutations identified by next-generation sequencing. Three commercially available antibodies - EPR13501 (Abcam), D2A8U (Cell Signaling), and HPA005456 (Sigma) - were optimised for IHC using cell line models and human tissue, and screened across a cohort of 45 gynaecological tumours. IHC was scored independently by three pathologists using an immunoreactive score. ARID1A mutation status was assessed using two independent sequencing platforms and the concordance between ARID1A mutation and protein expression was evaluated using Receiver Operating Characteristic statistics. Overall, 21 ARID1A mutations were identified in 14/43 assessable tumours (33%), the majority of which were predicted to be deleterious. Mutations were identified in 6/17 (35%) ovarian clear cell carcinomas, 5/8 (63%) ovarian endometrioid carcinomas, 2/5 (40%) endometrial carcinomas, and 1/7 (14%) carcinosarcomas. ROC analysis identified greater than 95% concordance between mutation status and IHC using a modified immunoreactive score for all three antibodies allowing a definitive cut-point for ARID1A mutant status to be calculated. Comprehensive assessment of concordance of ARID1A IHC and mutation status identified EPR13501 as an optimal antibody, with 100% concordance between ARID1A mutation status and protein expression, across different gynaecological histological subtypes. It delivered the best inter-rater agreement between all pathologists, as well as a clear cost-benefit advantage. This could allow patients to be accurately stratified based on their ARID1A IHC status into early phase clinical trials.

Abstract 788: Modeling tumor microenvironmental heterogeneity identifies CREBBP as a novel tumor suppressor in breast cancer

Solid tumors display significant histological, genetic and micro-environmental intra-tumor heterogeneity that can change substantially over the course of their evolutionary trajectory. In particular, changes in the micro-environmental complexity within breast cancer such as hypoxic and nutrient deplete environments are associated with aggressive disease and a poor patient outcome.

We sought to identify novel driver alterations in aggressive disease by employing a functional genomics screen in a 3-dimensional model of breast cancer progression that more accurately recapitulates in vivo micro-environmental heterogeneity. Screening of the top 200 recurrently mutated genes in breast cancer in cancer cell line spheroids identified several genes whose silencing impacted growth. A second targeted validation screen in a larger panel of triple negative cell line models showed that silencing of the histone acetyltransferase CREBBP, promoted growth in 3D but had limited effect under traditional 2D culture conditions.

Investigation of TCGA and METABRIC datasets showed that CREBBP was more frequently mutated in triple negative breast cancers (TNBCs) and at least a third of TNBCs also displayed gene haploinsufficiency or complete loss of CREBBP. Interrogation of expression and proteomic datasets showed that loss of CREBBP resulted in the upregulation of the pro-proliferative transcription factor FOXM1. Significantly, this conserved FOXM1-driven transcriptional programme was also seen in multiple solid tumors with CREBBP alterations including lung, oesophageal, bladder and endometrial cancers. This was recapitulated in several CREBBP deficient cells where we identified that FOXM1 is driving altered metabolism, allowing cancer cells to grow under nutrient stress conditions.

In summary, CREBBP is a bona fide tumor suppressor in up to a third of TNBCs, as well as a wide range of other solid tumors. CREBBP-altered tumors display up-regulation of FOXM1, which alters cancer cell metabolism under nutrient stress conditions. Moreover, CREBBP-altered tumors are selectively sensitive to small molecule inhibitors that target FOXM1 activity, suggesting that this maybe a viable targeted therapeutic approach for CREBBP altered cancers.

Citation Format: Barrie Peck, Philip J. Bland, Patty T. Wai, Hannah Cottom, Sarah L. Maguire, Eamonn Morrison, Holly E. Barker, Divya Kriplani, Rebecca Marlow, Kalnisha Naidoo, Gareth Muirhead, Syed Haider, Frances Daley, Frederik Wallberg, Andrew N. Tutt, Rachael C. Natrajan. Modeling tumor microenvironmental heterogeneity identifies CREBBP as a novel tumor suppressor in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 788.

Abstract P2-02-01: Withdrawn

This abstract was withdrawn by the authors.

Evaluation of CDK12 Protein Expression as a Potential Novel Biomarker for DNA Damage Response-Targeted Therapies in Breast Cancer

Disruption of Cyclin-Dependent Kinase 12 (CDK12) is known to lead to defects in DNA repair and sensitivity to platinum salts and PARP1/2 inhibitors. However, CDK12 has also been proposed as an oncogene in breast cancer. We therefore aimed to assess the frequency and distribution of CDK12 protein expression by IHC in independent cohorts of breast cancer and correlate this with outcome and genomic status. We found that 21% of primary unselected breast cancers were CDK12 high, and 10.5% were absent, by IHC. CDK12 positivity correlated with HER2 positivity but was not an independent predictor of breast cancer-specific survival taking HER2 status into account; however, absent CDK12 protein expression significantly correlated with a triple-negative phenotype. Interestingly, CDK12 protein absence was associated with reduced expression of a number of DDR proteins including ATR, Ku70/Ku80, PARP1, DNA-PK, and γH2AX, suggesting a novel mechanism of CDK12-associated DDR dysregulation in breast cancer. Our data suggest that diagnostic IHC quantification of CDK12 in breast cancer is feasible, with CDK12 absence possibly signifying defective DDR function. This may have important therapeutic implications, particularly for triple-negative breast cancers. Mol Cancer Ther; 17(1); 306-15. ©2017 AACR.

SOX11 promotes invasive growth and ductal carcinoma in situ progression

Here, we show that SOX11, an embryonic mammary marker that is normally silent in postnatal breast cells, is expressed in many oestrogen receptor‐negative preinvasive ductal carcinoma in situ (DCIS) lesions. Mature mammary epithelial cells engineered to express SOX11 showed alterations in progenitor cell populations, including an expanded basal‐like population with increased aldehyde dehydrogenase (ALDH) activity, and increased mammosphere‐forming capacity. DCIS.com cells engineered to express SOX11 showed increased ALDH activity, which is a feature of cancer stem cells. The CD44+/CD24–/ALDH+ cell population was increased in DCIS.com cells that expressed SOX11. Upregulating SOX11 expression in DCIS.com cells led to increased invasive growth both in vitro and when they were injected intraductally in a mouse model of DCIS that recapitulates human disease. Invasive lesions formed sooner and tumour growth was augmented in vivo, suggesting that SOX11 contributes to the progression of DCIS to invasive breast cancer. We identified potential downstream effectors of SOX11 during both microinvasive and invasive tumour growth stages, including several with established links to regulation of progenitor cell function and prenatal developmental growth. Our findings suggest that SOX11 is a potential biomarker for DCIS lesions containing cells harbouring distinct biological features that are likely to progress to invasive breast cancer. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Immunohistochemistry: A diagnostic aid in differentiating primary epithelial ovarian tumors and tumors metastatic to the ovary

INTRODUCTION

Among cancers of the female genital tract, the incidence of ovarian cancer ranks below only carcinoma of the cervix and the endometrium. Recent years have witnessed significant development in the use of immunohistochemistry in diagnostic ovarian pathology.

MATERIALS AND METHODS

We received 95 specimens and biopsies of primary ovarian neoplasms and neoplasms metastatic to the ovary in a period of 2 years. Of these 30 cases were of the primary surface epithelial neoplasms and seven of metastatic tumors.

DISCUSSION

The most common tumors metastasizing to the ovary originate from the gastrointestinal tract followed by the endometrium. We used a panel of six markers including cytokeratin-7 (CK7), CK20, carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), estrogen receptor (ER) and Wilms' tumor 1 (WT1) to help classify various surface epithelial tumors as well as to differentiate them from tumors metastatic to the ovary.

CONCLUSION

CK7 is the most helpful marker to differentiate primary ovarian carcinoma from metastatic colorectal carcinoma of the ovary. Nearly, 96% of ovarian adenocarcinomas were positive for CK7 in contrast to metastatic colorectal, which showed only 25% positivity. We also found that CK7, CK20 and CEA are useful markers to differentiate primary serous tumors from primary mucinous tumors; however, these are less helpful in differentiating ovarian mucinous adenocarcinomas from colorectal adenocarcinomas metastasizing to the ovaries. WT1 helps in typing primary surface epithelial tumors of the ovary and is also significant in determining whether a serous carcinoma within the ovary is primary or metastatic.

Small Cell Variant of Renal Oncocytoma With Liver Metastases

Renal oncocytoma is a renal neoplasm considered to be benign. A small cell variant comprising predominantly of oncoblasts is rare. Metastases from a renal oncocytoma are extremely rare. A case of small cell variant of renal oncocytoma with liver metastases is described.

Oral health attitudes and behaviour as predisposing factor for dental caries experience among health professional and other professional college students of India

PURPOSE

The objective of the present study was to determine if there existed any difference between the attitudes and behaviour apart from dental caries status among health professional and other professional college students and to investigate the association of oral health attitudes and behaviour with dental caries.

MATERIALS AND METHODS

The Hiroshima University-Dental Behaviour Inventory (HU-DBI) questionnaire was used to survey 1824 young student population of Udaipur, India. Dental caries status was evaluated using the World Health Organization caries diagnostic criteria for decayed, missing and filled teeth and surfaces (DMFT and DMFS, respectively).

RESULTS

There was a significant difference (P < 0.05) between the health professional and other professional college students for various components of DMFT and DMFS. Moreover, health professional students reported significantly higher HU-DBI scores (better oral health attitudes and behaviour) than their comparative group. Untreated dental caries played a major contribution to the total DMFT scores in both the groups, with 0.23 and 0.28 mean decayed teeth reported among health professional and other professional students, respectively. Decayed and missing teeth components exhibited a significant negative correlation with HU-DBI scores, whereas a positive correlation existed with the filled teeth component.

CONCLUSIONS

A difference existed between the health professional and other professional students with regard to caries experience, oral health attitudes and behaviour. DMF indices and their components were related to most of the oral health attitudes and behaviours. Decayed and missing teeth components were negatively related while filled component was positively related to HU-DBI score.