Combination of EZH2 and ATM inhibition in BAP1-deficient mesothelioma

BACKGROUND

More than half of mesothelioma tumours show alterations in the tumour suppressor gene BAP1. BAP1-deficient mesothelioma is shown to be sensitive to EZH2 inhibition in preclinical settings but only showed modest efficacy in clinical trial. Adding a second inhibitor could potentially elevate EZH2i treatment efficacy while preventing acquired resistance at the same time.

METHODS

A focused drug synergy screen consisting of 20 drugs was performed by combining EZH2 inhibition with a panel of anti-cancer compounds in mesothelioma cell lines. The compounds used are under preclinical investigation or already used in the clinic. The synergistic potential of the combinations was assessed by using the Bliss model. To validate our findings, in vivo xenograft experiments were performed.

RESULTS

Combining EZH2i with ATMi was found to have synergistic potential against BAP1-deficient mesothelioma in our drug screen, which was validated in clonogenicity assays. Tumour growth inhibition potential was significantly increased in BAP1-deficient xenografts. In addition, we observe lower ATM levels upon depletion of BAP1 and hypothesise that this might be mediated by E2F1.

CONCLUSIONS

We demonstrated the efficacy of the combination of ATM and EZH2 inhibition against BAP1-deficient mesothelioma in preclinical models, indicating the potential of this combination as a novel treatment modality using BAP1 as a biomarker.

The 3q Oncogene SEC62 Predicts Response to Neoadjuvant Chemotherapy and Regulates Tumor Cell Migration in Triple Negative Breast Cancer

In the absence of targeted treatment options, neoadjuvant chemotherapy (NACT) is applied widely for triple-negative breast cancer (TNBC). Response to NACT is an important parameter predictive of oncological outcomes (progression-free and overall survival). An approach to the evaluation of predictive markers enabling therapy individualization is the identification of tumor driver genetic mutations. This study was conducted to investigate the role of SEC62, harbored at 3q26 and identified as a driver of breast cancer pathogenesis, in TNBC. We analyzed SEC62 expression in The Cancer Genome Atlas database, and immunohistologically investigated SEC62 expression in pre- and post-NACT tissue samples from 64 patients with TNBC treated at the Department of Gynecology and Obstetrics/Saarland University Hospital/Homburg between January 2010 and December 2018 and compared the effect of SEC62 on tumor cell migration and proliferation in functional assays. SEC62 expression dynamics correlated positively with the response to NACT (p ≤ 0.01) and oncological outcomes (p ≤ 0.01). SEC62 expression stimulated tumor cell migration (p ≤ 0.01). The study findings indicate that SEC62 is overexpressed in TNBC and serves as a predictive marker for the response to NACT, a prognostic marker for oncological outcomes, and a migration-stimulating oncogene in TNBC.

Long-term survival of breast cancer patients with brain metastases: subanalysis of the BMBC registry

BACKGROUND

Up to 30% of metastatic breast cancer (BC) patients develop brain metastases (BM). Prognosis of patients with BM is poor and long-term survival is rare. Identification of factors associated with long-term survival is important for improving treatment modalities.

PATIENTS AND METHODS

A total of 2889 patients of the national registry for BM in BC (BMBC) were available for this analysis. Long-term survival was defined as overall survival (OS) in the upper third of the failure curve resulting in a cut-off of 15 months. A total of 887 patients were categorized as long-term survivors.

RESULTS

Long-term survivors compared to other patients were younger at BC and BM diagnosis (median 48 versus 54 years and 53 versus 59 years), more often had HER2-positive tumors (59.1% versus 36.3%), less frequently luminal-like (29.1% versus 35.7%) or triple-negative breast cancer (TNBC) (11.9% versus 28.1%), showed better Eastern Cooperative Oncology Group (ECOG) performance status (PS) at the time of BM diagnosis (ECOG 0-1, 76.9% versus 51.0%), higher pathological complete remission rates after neoadjuvant chemotherapy (21.6% versus 13.7%) and lower number of BM (n = 1, BM 40.9% versus 25.4%; n = 2-3, BM 26.5% versus 26.7%; n ≥4, BM 32.6% versus 47.9%) (P < 0.001). Long-term survivors had leptomeningeal metastases (10.4% versus 17.5%) and extracranial metastases (ECM, 73.6% versus 82.5%) less frequently, and asymptomatic BM more often at the time of BM diagnosis (26.5% versus 20.1%), (P < 0.001). Median OS in long-term survivors was about two times higher than the cut-off of 15 months: 30.9 months [interquartile range (IQR) 30.3] overall, 33.9 months (IQR 37.1) in HER2-positive, 26.9 months (IQR 22.0) in luminal-like and 26.5 months (IQR 18.2) in TNBC patients.

CONCLUSIONS

In our analysis, long-term survival of BC patients with BM was associated with better ECOG PS, younger age, HER2-positive subtype, lower number of BM and less extended visceral metastases. Patients with these clinical features might be more eligible for extended local brain and systemic treatment.

Trophoblast Cell Surface Antigen 2 (TROP2) as a Predictive Bio-Marker for the Therapeutic Efficacy of Sacituzumab Govitecan in Adenocarcinoma of the Esophagus

INTRODUCTION

The Trophoblast cell surface antigen 2 (TROP2) is expressed in many carcinomas and may represent a target for treatment. Sacituzumab govitecan (SG) is a TROP2-directed antibody-drug conjugate (ADC). Nearly nothing is known about the biological effectiveness of SG in esophageal adenocarcinoma (EAC).

MATERIAL AND METHODS

We determined the TROP2 expression in nearly 600 human EAC. In addition, we used the EAC cell lines (ESO-26, OACM5.1C, and FLO-1) and a xenograft mouse model to investigate this relationship.

RESULTS

Of 598 human EACs analyzed, 88% showed varying degrees of TROP2 positivity. High TROP2 positive ESO-26 and low TROP2 positive OACM5.1C showed high sensitivity to SG in contrast to negative FLO-1. In vivo, the ESO-26 tumor shows a significantly better response to SG than the TROP2-negative FLO-1 tumor. ESO-26 vital tumor cells show similar TROP2 expression on all carcinoma cells as before therapy initiation, FLO-1 is persistently negative.

DISCUSSION

Our data suggest that sacituzumab govitecan is a new therapy option in esophageal adenocarcinoma and the TROP2 expression in irinotecan-naïve EAC correlates with the extent of treatment response by sacituzumab govitecan. TROP2 is emerging as a predictive biomarker in completely TROP2-negative tumors. This should be considered in future clinical trials.

Combined inhibition of EZH2 and ATM is synthetic lethal in BRCA1-deficient breast cancer

Background

The majority of BRCA1-mutant breast cancers are characterized by a triple-negative phenotype and a basal-like molecular subtype, associated with aggressive clinical behavior. Current treatment options are limited, highlighting the need for the development of novel targeted therapies for this tumor subtype.

Methods

Our group previously showed that EZH2 is functionally relevant in BRCA1-deficient breast tumors and blocking EZH2 enzymatic activity could be a potent treatment strategy. To validate the role of EZH2 as a therapeutic target and to identify new synergistic drug combinations, we performed a high-throughput drug combination screen in various cell lines derived from BRCA1-deficient and -proficient mouse mammary tumors.

Results

We identified the combined inhibition of EZH2 and the proximal DNA damage response kinase ATM as a novel synthetic lethality-based therapy for the treatment of BRCA1-deficient breast tumors. We show that the combined treatment with the EZH2 inhibitor GSK126 and the ATM inhibitor AZD1390 led to reduced colony formation, increased genotoxic stress, and apoptosis-mediated cell death in BRCA1-deficient mammary tumor cells in vitro. These findings were corroborated by in vivo experiments showing that simultaneous inhibition of EZH2 and ATM significantly increased anti-tumor activity in mice bearing BRCA1-deficient mammary tumors.

Conclusion

Taken together, we identified a synthetic lethal interaction between EZH2 and ATM and propose this synergistic interaction as a novel molecular combination for the treatment of BRCA1-mutant breast cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-022-01534-y.

Characteristics of patients with brain metastases from human epidermal growth factor receptor 2-positive breast cancer: subanalysis of Brain Metastases in Breast Cancer Registry

Background

Up to 40% of patients with metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer develop brain metastases (BMs). Understanding of clinical features of these patients with HER2-positive breast cancer and BMs is vital.

Patients and methods

A total of 2948 patients from the Brain Metastases in Breast Cancer registry were available for this analysis, of whom 1311 had primary tumors with the HER2-positive subtype.

Results

Patients with HER2-positive breast cancer and BMs were—when compared with HER2-negative patients—slightly younger at the time of breast cancer and BM diagnosis, had a higher pathologic complete response rate after neoadjuvant chemotherapy and a higher tumor grade. Furthermore, extracranial metastases at the time of BM diagnosis were less common in HER2-positive patients, when compared with HER2-negative patients. HER2-positive patients had more often BMs in the posterior fossa, but less commonly leptomeningeal metastases. The median overall survival (OS) in all HER2-positive patients was 13.2 months (95% confidence interval 11.4-14.4). The following factors were associated with shorter OS (multivariate analysis): older age at BM diagnosis [≥60 versus <60 years: hazard ratio (HR) 1.63, P < 0.001], lower Eastern Cooperative Oncology Group status (2-4 versus 0-1: HR 1.59, P < 0.001), higher number of BMs (2-3 versus 1: HR 1.30, P = 0.082; ≥4 versus 1: HR 1.51, P = 0.004; global P = 0.015), BMs in the fossa anterior (HR 1.71, P < 0.001), leptomeningeal metastases (HR 1.63, P = 0.012), symptomatic BMs at diagnosis (HR 1.35, P = 0.033) and extracranial metastases at diagnosis of BMs (HR 1.43, P = 0.020). The application of targeted therapy after the BM diagnosis (HR 0.62, P < 0.001) was associated with longer OS. HER2-positive/hormone receptor-positive patients showed longer OS than HER2-positive/hormone receptor-negative patients (median 14.3 versus 10.9 months; HR 0.86, P = 0.03), but no differences in progression-free survival were seen between both groups.

Conclusions

We identified factors associated with the prognosis of HER2-positive patients with BMs. Further research is needed to understand the factors determining the longer survival of HER2-positive/hormone receptor-positive patients.

•

Patients with HER2-positive BMs from breast cancer have the best prognosis compared with other tumor subtypes.

•

Among HER2-positive patients, hormone receptor-positive patients have the longest survival.

•

HER2-targeted therapy is significantly associated with a better prognosis in patients with BMs.

•

On average, two HER2-targeted therapy lines were administered prior to the development of BMs.

•

New compounds are urgently needed to improve the outcome of this subgroup of patients.

Platelet-rich plasma (PRP) in oncological patients: long-term oncological outcome analysis of the treatment of subcutaneous venous access device scars in 89 breast cancer patients

Purpose

Platelet-rich plasma (PRP) is widely used product, and meta-analyses showed this product to be beneficial when applied to a wound area. This study group has already demonstrated increased patient satisfaction and lower complication rates in breast cancer patients who received PRP after removal of their subcutaneous venous access device. This work is a follow-up analysis focusing on oncologic safety. Currently, there is no long-term data on the use of PRP products in cancer patients available yet.

Methods

Between the years 2012–2016, venous access device removal was supported with the application of Arthrex ACP^® (Autologous Conditioned Plasma)—a PRP product to improve the wound-healing process. All surgeries were performed in the breast cancer center of the municipal hospital of Cologne, Holweide, Germany. 35 patients received an application of Arthrex ACP^® after port removal compared to the control group of 54 patients. Endpoints were local recurrence-free, distant recurrence-free as well as overall survival.

Results

Median follow-up was 45 months. No (0) adverse events were shown for cancer recurrence within the subcutaneous venous access device scar area. Thus, there seems to be no local oncogenic potential of the PRP product. All other endpoints as well as any-cause death numerically favor PRP use.

Conclusion

PRP products such as Arthrex ACP^® seem to be oncological inert when applied after removal of subcutaneous access devices. This is the first study providing long-term data about overall survival, distant recurrence-free and local recurrence-free survival after applying PRP in high-risk cancer patients.

Improving Breast Conserving Surgery Using the Faxitron® OR Specimen Radiography System - A Complication Analysis, Cost Evaluation and Literature Review

BACKGROUND/AIM

The combination of pre-surgical clip placement and hook-wire guided surgery is considered the gold standard for adequately locating non-palpable lesions during breast conserving surgery. After surgical removal of the segment, radiography is required to confirm clip removal, increasing surgical time, post-surgical complication rates, and cost.

PATIENTS AND METHODS

We performed a retrospective analysis, using the Faxitron^® in-theater specimen radiography system, of the following primary endpoints: surgical time and complication rates. The secondary endpoints were cost effectiveness and clip-location rates. The Control cohort included breast conserving surgery patients prior to May 2019 (n=150) and the Validation cohort included breast conserving surgery patients after May 2019 (n=53).

RESULTS

The analysis showed an improvement in surgical time when using the Faxitron^® system, which is directly linked to a benefit in cost effectiveness. A numerical benefit in complication rates was also shown. A subgroup analysis showed a significant advantage in surgical time for breast conserving surgery plus sentinel node biopsy and open breast biopsies.

CONCLUSION

Use of the Faxitron^® system significantly reduces surgical time, which increases cost efficiency while maintaining a low complication rate.

Correlation analysis of resected breast tissue and implant volume after mastectomy and its association with breast density

BACKGROUND

The current methods for calculating the ideal implant volume for breast reconstruction are based on pre- or intraoperative volume measurements of the existing breast volume and do not take into account the individual breast density of the woman. This study aims is to identify objective parameters that can help to improve the optimal implant selection.

MATERIALS AND METHODS

This retrospective analysis includes 198 breast cancer patients who underwent mastectomy. Breast densities (ACR) measured in mammography and MRI were compared with the removed breast tissue weight and volume of the implants used. In addition, the resected weight was compared directly with the implant volume to calculate a mathematical function.

RESULTS

There was no significant correlation between the ACR values and the resected weights [correlation coefficient: mammography:- 0.117 (p = 0.176), MRI - 0.033 (p = 0.756)]. A negative correlation between the implant volumes and both imaging methods could be demonstrated [correlation coefficient: mammography - 0.268; p = 0.002; MRI was - 0.200 (p = 0.055)]. A highly significant correlation between the resected weights and the implant volumes (correlation coefficient 0.744; p < 0.001) was observed. This correlation corresponds to a power function (y = 34.71 x^0.39), in which any resected weight can be used for the variable x to calculate the implant volume.

CONCLUSION

We were able to show that there is a significant correlation between the resected breast tissue and the implant volume. With our novel potency function, the appropriate implant volume can be calculated for any resected weight making it easier for the surgeon to choose a fitting implant in a simple and more objective manner.

Intraoperative central nipple biopsy in nipple-sparing mastectomy- A retrospective analysis of 211 patients

Subcutaneous nipple sparing mastectomies (NSM) are an important tool in modern oncoplastic surgery. Especially when an immediate implant-based reconstruction (IBR) is desired, clean margins are of the utmost importance. Central nipple biopsies during surgery serve two main purposes. Most importantly, it is hypothesized that intraoperative pathological evaluation of this biopsy may increase clean margin resection rates. In addition, a general recurrence risk reduction may occur due to the elimination of glandular and ductal components within the nipple. This analysis is a single center, multi-surgeon, retrospective, head to head analysis. Starting in March 2015, intraoperative central nipple biopsy in NSMs with IBR was introduced at the Municipal Breast Cancer Centre Cologne, Holweide, Germany. This trial retrospectively evaluates global complication rates, clean margin status and local recurrence rates for cohort 1 (NSM/no nipple biopsy, n = 103) vs. cohort 2 (NSM with nipple biopsy, n = 108) Median follow-up was 15 months. All implant-based reconstruction procedures used an epipectoral implant pocket. Cohorts were comparable. Global complication rates slightly favored the nipple biopsy cohort with respects to implant loss rate. An involved central nipple biopsy was found in 4.6% (n = 5/108) of the performed NSM procedures leading to the immediate removal of the nipple areola complex. All positive retro-areolar biopsies correlated with a positive nipple biopsy. However, in n = 1 case we found DCIS discontinual proliferation with an involved nipple biopsy, without a correlating positive retro-areolar biopsy (ie, 1 false-negative case was prevented). For the 15 month follow-up, there was no case of local recurrence within nipple areola complex for both cohorts. With this retrospective head to head analysis of 211 patients, it was shown that the central nipple biopsy correlates well with the retro-areolar biopsy. There may be a reduction in false negative rates. The procedure is safe to use and should be offered to NSM patients.

Genomic Signatures in Luminal Breast Cancer

Background

Breast cancer is a very heterogeneous disease and luminal breast carcinomas represent the hormone receptor-positive tumors among all breast cancer subtypes. In this context, multigene signatures were developed to gain further prognostic and predictive information beyond clinical parameters and traditional immunohistochemical markers.

Summary

For early breast cancer patients these molecular tools can guide clinicians to decide on the extension of endocrine therapy to avoid over- and undertreatment by adjuvant chemotherapy. Beside the predictive and prognostic value, a few genomic tests are also able to provide intrinsic subtype classification. In this review, we compare the most frequently used and commercially available molecular tests (OncotypeDX®, MammaPrint®, Prosigna®, EndoPredict®, and Breast Cancer Index^SM). Moreover, we discuss the clinical utility of molecular profiling for advanced breast cancer of the luminal subtype.

Key Messages

Multigene assays can help to de-escalate systemic therapy in early-stage breast cancer. Only the Oncotype DX® and MammaPrint®test are validated by entirely prospective and randomized phase 3 trials. More clinical evidence is needed to support the use of genomic tests in node-positive disease. Recent developments in high-throughput sequencing technology will provide further insights to understand the heterogeneity of luminal breast cancers in early-stage and metastatic disease.

Abstract P4-02-19: First reported use of the Faxitron LOCalizer™ Radiofrequency Identification (RFID) system in the axilla- A pilot trial in targeted axillary dissection (TAD)

Introduction: Adequately marking suspicious lymph nodes before neoadjuvant chemotherapy in breast cancer patients is commonly done by introducing a titanium clip followed by stereotactic hook wire location. However, clip dislocation and/or wire dislocation are common problems. Furthermore, locating a clip within the axilla is problematic since stereotactic location may be anatomically challenging. An ideal solution would be a clip which can be easily found without the use of a stereotactic intervention. This pilot trial proves the concept of using radiofrequency identification devices (RFID) in targeted axillary dissection (TAD).Methods: This pilot trial represents a single center, consecutively recruited, evaluation (n=10) for targeted axillary dissection using the Faxitron LOCalizer™ radiofrequency identification chip system. Patients were given the choice between wire guided TAD vs. LOCalizer™ TAD. Primary endpoints were: percentage of successful location /failure to locate. Secondary endpoints were major and minor complication rates as well as surgeon evaluated outcome.Results: Primary endpoints showed a 100% location rate of the suspicious lymph nodes at a 0% major complication (revision surgery) rate. Additional guided wire marking was not necessary for lymph node location. Surgeons evaluated the new system as being safe to use and only slightly more difficult to place than a standard clip or a wire system.Conclusion: This pilot trial proved the concept of TAD via a RFID system. When using this system, preoperative stereotactic lymph node marking is no longer required, thus patients may be spared additional x-ray exposure. Using the LOCalizer™ system should therefore be considered for any TAD.

Citation Format: Wolfram Malter, Christian Eichler, Julian Puppe, Fabishy Thangarajah, Peter Mallmann, Barbara Krug, Mathias Warm, Johannes Holtschmidt. First reported use of the Faxitron LOCalizer™ Radiofrequency Identification (RFID) system in the axilla- A pilot trial in targeted axillary dissection (TAD) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-02-19.

Joining to promote young talents: an experience report from the first German Summer School for Obstetrics and Gynaecology for medical students

PURPOSE

The Commission for the Promotion of Young Talents of the German Society for Gynaecology and Obstetrics e.V. was founded in 2017, aiming to inspire medical students for a career in obstetrics and gynaecology by developing a concept for the first German Summer School in this field. Here, medical students shall be introduced to this multifaceted specialty and have their interest in it kindled.

METHODS

This article reports about the experiences of the first gynaecological summer school which was held at the University Hospital Heidelberg for 2 days in August 2018. The programme included keynote presentations, discussion roundtables and skills-lab training. To assess students' related satisfaction, and to improve future projects, an evaluation survey with seven items and two open-comment questions was given to each participant after the event.

RESULTS

Mostly female students [n (♀) = 37, 93%; n (♂) = 3, 7%] from 15 different medical universities from all over Germany participated. Available places were booked within 1 week. Participants were in their clinical part of their studies between the 5th and 16th semester. The average rating of the event was excellent with 1.1 points (1 = best-5 = worst), while the selection of topics scored lowest marks with an average rating of 1.7 points.

CONCLUSION

Due to the great success, the high demand and the student's positive evaluation, annual summer schools in obstetrics and gynaecology are planned. Because most of the participating students have shown a high interest and have appropriate education in the domain, the information content of keynote presentations could be increased above basic level in future projects.

EZH2 Is Overexpressed in BRCA1-like Breast Tumors and Predictive for Sensitivity to High-Dose Platinum-Based Chemotherapy

PURPOSE

BRCA1-deficient breast cancers carry a specific DNA copy-number signature ("BRCA1-like") and are hypersensitive to DNA double-strand break (DSB) inducing compounds. Here, we explored whether (i) EZH2 is overexpressed in human BRCA1-deficient breast tumors and might predict sensitivity to DSB-inducing drugs; (ii) EZH2 inhibition potentiates cisplatin efficacy in Brca1-deficient murine mammary tumors.

EXPERIMENTAL DESIGN

EZH2 expression was analyzed in 497 breast cancers using IHC or RNA sequencing. We classified 370 tumors by copy-number profiles as BRCA1-like or non-BRCA1-like and examined its association with EZH2 expression. Additionally, we assessed BRCA1 loss through mutation or promoter methylation status and investigated the predictive value of EZH2 expression in a study population of breast cancer patients treated with adjuvant high-dose platinum-based chemotherapy compared with standard anthracycline-based chemotherapy. To explore whether EZH2 inhibition by GSK126 enhances sensitivity to platinum drugs in EZH2-overexpressing breast cancers we used a Brca1-deficient mouse model.

RESULTS

The highest EZH2 expression was found in BRCA1-associated tumors harboring a BRCA1 mutation, BRCA1-promoter methylation or were classified as BRCA1 like. We observed a greater benefit from high-dose platinum-based chemotherapy in BRCA1-like and non-BRCA1-like patients with high EZH2 expression. Combined treatment with the EZH2 inhibitor GSK126 and cisplatin decreased cell proliferation and improved survival in Brca1-deficient mice in comparison with single agents.

CONCLUSIONS

Our findings demonstrate that EZH2 is expressed at significantly higher levels in BRCA1-deficient breast cancers. EZH2 overexpression can identify patients with breast cancer who benefit significantly from intensified DSB-inducing platinum-based chemotherapy independent of BRCA1-like status. EZH2 inhibition improves the antitumor effect of platinum drugs in Brca1-deficient breast tumors in vivo.

Clinical impact of PD-L1 and PD-1 expression in squamous cell cancer of the vulva

PURPOSE

Squamous cell carcinoma of the vulva (SQCV) is the fifth most common cancer in women and accounts for about 5% of all genital cancers in women. The PD-L1 signaling pathway is activated in many malignant neoplasms and its blockade enhances anti-cancer immunity. The aim of our study was to examine the protein expression of PD-L1 and PD-1 in squamous cell cancer of the vulva, its correlations with clinicopathologic features and prognostic value.

METHODS

Patients with SQCV treated in one institution were used for the analyses. PD-L1 immunohistochemistry was performed on 4 µm-thick section of the respective FFPE tissue blocks using the 28-8 antibody. PD-L1 scoring was performed separately for tumour cells (TC) and tumour associated immune cells. DNA was extracted to determine HPV status. Kaplan-Meier estimates for disease-free-survival and overall-survival were calculated and compared by log-rank test.

RESULTS

PD-L1 expression in tumour cells could be observed in 32.9% of the patients. The expression of PD-L1 in peritumoural immune cells was confirmed in 91.4% of the patients. A significant correlation between PD-L1 expression in tumour cells and tumour stage was detected (p = 0.007). PD-L1 expression was independent from HPV status. Using the log-rank test we could not prove any significant differences in disease-free survival (p = 0.434) and overall survival (p = 0.858). Regression analysis showed that nodal status is a predictive factor of survival (p < 0.001).

CONCLUSION

The present study showed that a relevant amount of patients with squamous cell cancer of the vulva express PD-L1 in both, tumour cells and tumour-associated immune cells. Furthermore, the significant correlation of PD-L1 expression in TCs with tumour stage indicated the clinical impact of PD-L1 expression during tumour development. These data indicate that SQCV might be amenable to immune checkpoint-inhibition and constitute a rational for the future clinical trials.

Abstract P4-08-21: Gene expression profiling – a decision impact analysis – Decision dependency on OncotypeDX and EndoPredict as a function of oncological work experience

Background: Estimating distant recurrence risk in women with estrogen receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer is still challenging. Oncotype DX and EndoPredict are two competing, gene expression-based tests predicting the likelihood of recurrent disease. We analyzed the difference in oncological decision making with and without the knowledge of gene expression tests.

Methods: We performed a retrospective, analysis including n = 192 patients diagnosed with G2, HR+, Her2- breast cancer between 2011 and 2015 at the Municipal Breast Cancer Centre Cologne, Germany. All 192 patients received an evaluation by OncotypeDX or EndoPredict. An oncological tumor board (TB) with knowledge of these results served as baseline (control group). This baseline was compared to the treatment decision (adjuvant chemotherapy Yes vs. No) reached by oncologists with different experience levels (less than 5 years, between 5 and 15 years and more than 15 years) who were not provided the OncotypeDX or EndoPredict scores. All clinicians had access to clinical as well to histopathological data only.

Results: Within the EndoPredict group no significant decrease between overall TB decision (adjuvant chemotherapy Yes) 48.1% vs. 15+ years = 39.2%, 5-15 years = 39.2% and &lt;5 years = 50.6% group could be shown. Endopredict seemed to overestimate the clinical risk as judged by experienced oncologists. Within the OncotypeDX cohort we were able to find a significant decrease between overall TB decision (chemotherapy Yes) 41.6% vs. 15+ years = 42.5%, 5-15 years = 50.4% and &lt;5 years = 55.6% group (p&lt;0.05). In addition, inexperience led to a significant and numerically greater increase in chemotherapy recommendation. An exploratory subgroup analysis showed significant differences in TB vs oncologist decision for Ki67 &gt;14%, tumor sizes larger than pT2, pN1 and postmenopausal patients for all experience levels.

Conclusions: Overall, results for the EndoPredict group were inconclusive. A significant reduction of chemotherapy recommendation was shown for all experience levels in the Oncotype subgroup however, with a maximum reduction of 14.2%. A subgroup analysis showed that differences in decision making were most likely for patients with a Ki67 &gt;14%, tumor sizes larger than pT2, pN1 and postmenopausal patients. Since these are the patients where the question of pro/contra chemotherapy is most important, it is the opinion of this study group that gene expression testing is especially pertinent for these patients.

Citation Format: Eichler C, Fromme J, Puppe J, Malter W, Paepke S, Warm M. Gene expression profiling – a decision impact analysis – Decision dependency on OncotypeDX and EndoPredict as a function of oncological work experience [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 P4-08-21.

Neoadjuvant Therapy of Cervical Carcinoma with the Angiogenesis Inhibitor Bevacizumab: a Single-Centre Analysis

Introduction Cervical cancer is the fourth most frequent cancer in women worldwide. Addition of the VEGF antibody bevacizumab in combination with platinum-containing chemotherapy achieved an improvement in overall survival in advanced cervical cancer. To date there are no data on neoadjuvant use of bevacizumab. We therefore studied the benefit of neoadjuvant combined therapy with bevacizumab in a group of cervical cancer patients.

Patients and Methods This retrospective cohort study analysed 14 patients with cervical cancer FIGO stages 1b1 to IV who received neoadjuvant platinum-containing chemotherapy in combination with bevacizumab. The comparative cohort consisted of 16 patients who were treated with neoadjuvant platinum-containing chemotherapy alone. The response rates were determined by means of preoperative clinical examination, diagnostic imaging (RECIST), changes in tumour markers (SCC) and by histopathology.

Results A clinical response was found in 93.8% (n = 15) of patients after bevacizumab-free therapy and in 100% (n = 14) of the patients who were treated with bevacizumab in addition. Combined therapy with bevacizumab led to a higher rate of clinical complete remission (42.9 vs. 12.5%; p = 0.072) and significantly improved the reduction in tumour size (Δ longest diameter: 3.7 vs. 2.5 cm; p = 0.025). Downgrading was observed in 100% of all patients treated with bevacizumab compared with 75% in the control arm. The rate of pathological complete remission (pCR) was not altered significantly (28.6% [n = 4] vs. 37.5% [n = 6]; p = 0.460).

Discussion Overall, combined therapy with bevacizumab led to a better clinical response. Operability was therefore improved more often. Because of the small patient cohort, larger prospective studies are necessary to validate the effect of neoadjuvant combined therapy with bevacizumab.

A Head to Head Comparison Between SurgiMend® - Fetal Bovine Acellular Dermal Matrix and Tutomesh® - A Bovine Pericardium Collagen Membrane in Breast Reconstruction in 45 Cases

BACKGROUND/AIM

The use of acellular dermal matrices (ADM) has become a widely used option in breast reconstruction. A great deal of literature is available, totaling over 3,200 ADM reconstructions. Head-to-head comparisons between SurgiMend® and Tutomesh® are not yet reported. These are the first comparative clinical data reported on the use of Tutomesh® in breast reconstruction. Postoperative complication rates and costs for these devices were evaluated.

PATIENTS AND METHODS

This is a retrospective analysis of a 2-year experience with both SurgiMend® - fetal bovine acellular dermal matrix and Tutomesh® - a bovine pericardium collagen membrane in breast reconstruction in 45 cases from 2014-2015.

RESULTS

Forty-five patients received a total of 45 implant-based reconstructions using SurgiMend® (18 cases; 40%) or Tutomesh® (27 cases; 60%). Gross complication rates were 27.8% for SurgiMend® and 37.0% for Tutomesh® including hematoma, postoperative skin irritation, infection, red breast syndrome and revision surgery. The most common complication was postoperative red breast syndrome. Severe complications requiring revision surgery did not differ significantly in patients treated with SurgiMend® (0 cases, 0%) compared to Tutomesh® (1 case, 3.7%).

CONCLUSION

This retrospective analysis shows similar overall clinical complication rates for Tutomesh® and SurgiMend®. Severe complication rates are comparable to those reported in literature for both products. Although the retrospective nature of this work limits its clinical impact, it is possible to opt for the cheaper alternative (Tutomesh®).

Detection of Ductal Carcinoma In Situ by Ultrasound and Mammography: Size-dependent Inaccuracy

BACKGROUND

Retrospective analysis of breast cancer imaging methods is a common tool for evaluating the effectiveness of ultrasound and mammography regarding ductal carcinoma in situ (DCIS). No large number subpopulation of pure DCIS has been reported. It is however known that mammography and ultrasound underestimate tumor dimension with increasing tumor size. We aimed to quantify this discrepancy.

MATERIALS AND METHODS

This retrospective analysis reviewed the ultrasound and mammography data from 173 patients with DCIS at the University of Cologne - Department of Gynecology and Obstetrics between the years 2007 and 2010. Of these 173 patients, 34 fulfilled the DCIS analysis requirements and were evaluated in this study.

RESULTS

Overall, ultrasound underestimated tumor size 79.4% of the time, while overestimating only 20.6% of the time. Mammography underestimated tumor size in 50%, overestimated in 38.2%, correctly estimating in 11.8%. Over and underestimation distributions differed drastically above and a cut-off point of ≤2 cm actual tumor size, with a significant shift toward severe underestimation by both methods above a tumor size of 2 cm. DCIS misestimation was defined as the absolute value of the difference between actual tumor size and pre-surgical measurement by an imaging method. Mean DCIS size misestimation (actual tumor size ≤2 cm) was 3 mm for ultrasound and 6.2 mm for mammography.

CONCLUSION

We support previous findings that ultrasound and mammography lose accuracy with increasing tumor size. Nonetheless, ultrasound may be more useful in estimation of DCIS size for tumors ≤2 cm than previously expected.

Duty Rosters and Workloads of Obstetricians in Germany: Results of a Germany-wide Survey

BACKGROUND

Compiling a daily hospital roster which complies with existing laws and tariff regulations and meets the requirements for ongoing professional training while also taking the legal regulations on the health of employees into account makes planning the duty roster a challenge. The aim of this study was to obtain a realistic picture of existing duty roster systems and of the current workloads of obstetricians in Germany.

METHOD

This online survey was sent to 2770 physicians training to become obstetricians or specializing in specific areas of obstetric care. The survey consisted of an anonymized 95-item questionnaire which collected data on different types of duty roster systems and the workload of obstetricians in Germany for the period from 17.02.2015 to 16.05.2015.

RESULTS

Out of a total of 2770 physicians who were contacted, 437 (16%) completed the questionnaire. Across all forms of care, the care provided outside normal working hours usually (75%) consisted of a combination of regular working times and on-call duty or even consisted entirely of standby duty. Level I perinatal centers were most likely 20% (n = 88) to have a shift system in place. Working a shift system was significantly more common in care facilities which had previously carried out a job analysis. The number of physicians in hospitals who are present during the night shift was higher in facilities with higher numbers of births and in facilities which offered higher levels of care. In addition to regularly working overtime and the fact that often not all the hours worked were recorded, it was notable that the systems used to compile duty rosters often did not comply with legal regulations or with collectively agreed working hours nor were they compatible with the staff planning requirements.

OUTLOOK

The results of this study show that the conditions of work, the working times, and the organization of working times in obstetric departments are in need of improvement. Recording the actual times worked together with an analysis of the activities performed during working times and while on standby would increase the level of transparency for employers and employees.

The conjugated antimetabolite 5-FdU-ECyd and its cellular and molecular effects on platinum-sensitive vs. -resistant ovarian cancer cells in vitro

Background

Resistance to platinum-based chemotherapy is a clinical challenge in the treatment of ovarian cancer (OC) and limits survival. Therefore, innovative drugs against platinum-resistance are urgently needed. Our therapeutic concept is based on the conjugation of two chemotherapeutic compounds to a monotherapeutic pro-drug, which is taken up by cancer cells and cleaved into active cytostatic metabolites. We explore the activity of the duplex-prodrug 5-FdU-ECyd, covalently linking 2'-deoxy-5-fluorouridine (5-FdU) and 3'-C-ethynylcytidine (ECyd), on platinum-resistant OC cells.

Methods

In vitro assays and RNA-Sequencing were applied for characterization of 5-FdU-ECyd treated platinum-sensitive A2780 and isogenic platinum-resistant A2780cis and independent platinum-resistant Skov-3-IP OC cells.

Results

Nano molar 5-FdU-ECyd concentrations induced a rapid dose-dependent decline of cell viability in platinum-sensitive and -resistant OC cells. The effect of 5-FdU-ECyd was accompanied by the formation of DNA double strand breaks and apoptosis induction, indicated by a strong increase of pro-apoptotic molecular markers. Moreover, 5-FdU-ECyd efficiently decreased migration of platinum-resistant OC cells and inhibited clonogenic or spheroidal growth. Transcriptome analysis showed early up-regulation of CDKN1A and c-Fos in both, platinum-resistant and -sensitive cells after 5-FdU-ECyd treatment and de-regulation of distinct cellular pathways involved in cell cycle regulation, apoptosis, DNA-damage response and RNA-metabolism. Combined treatment of 5-FdU-ECyd and cisplatin did not show a synergistic cellular response, suggesting the potential use of 5-FdU-ECyd as a monotherapeutic agent.

Conclusion

Our data provide novel mechanistic insight into the anti-tumor effect of 5-FdU-ECyd and we hypothesize that this duplex-prodrug could be a promising therapeutic option for OC patients with resistance to platinum-based chemotherapy.

The activity of the conjugated antimetabolite 5-FdU-ECyd against platinum-resistant ovarian cancer

e17077

Background: Primary or secondary resistance to platinum-based chemotherapy is an important clinical challenge in the treatment of ovarian cancer (OC) and limits survival. Therefore, the development of innovative drugs against platinum resistance is urgently needed. Our therapeutic concept is based on the conjugation of two chemotherapeutic compounds to a monotherapeutic pro-drug, which is taken up by cancer cells and is subsequently cleaved into several active cytostatic metabolites. Our in vitro study evaluates the effects of the conjugated antimetabolite 5-FdU-ECyd, consisting of 2-deoxy-5-fluorouridine (5-FdU) and ethynylcytidine (ECyd), on platinum-resistant OC cells. Methods: In vitro assays and RNA-Seq (Illumina) were applied for characterization of 5-FdU-ECyd treated platinum-sensitive A2780 and isogenic platinum-resistant A2780cis as well as independent platinum-resistant Skov-3-IP OC cells. Results: Nano molar 5-FdU-ECyd concentrations induced a rapid dose-dependent decline of cell viability in platinum-sensitive and platinum-resistant OC cells. The cytotoxicity of 5-FdU-ECyd was accompanied by the formation of DNA double strand breaks and by the induction of apoptosis, indicated by a strong increase of pro-apoptotic molecular markers (caspase-3/7 activation, PARP-cleavage). Moreover, 5-FdU-ECyd efficiently decreased cell migration of platinum-resistant OC cells and inhibited other tumor-associated cellular functions, such as clonogenic or spheroidal growth. Transcriptome analysis indicated that, independently of platinum-resistance status, 5-FdU-ECyd influences distinct cellular pathways, involved in cell cycle regulation, apoptosis, DNA-damage response and RNA/pyrimidine metabolism. Combination treatment of 5-FdU-ECyd and platin did not show a synergistic cellular response, suggesting the potential use of 5-FdU-ECyd as a monotherapeutic agent. Conclusions: Our data provide a rationale to characterize the effect of 5-FdU-ECyd in a pre-clinical in vivo setting. We hypothesize that this conjugate is a promising therapeutic option for OC patients with resistance to conventional platinum-based chemotherapy.

Evaluation of QTc Interval Prolongation in Breast Cancer Patients after Treatment with Epirubicin, Cyclophosphamide, and Docetaxel and the Influence of Interobserver Variation

BACKGROUND

Chemotherapy with anthracyclines is associated with life-threatening electrocardiographic alterations including corrected QT (QTc) interval prolongation.

PATIENTS AND METHODS

In this study we assessed the effect of epirubicin, cyclophosphamide, and docetaxel (EC-Doc) on the QTc interval in 10 patients with early breast cancer. Cardiac toxicity was assessed with symptoms, transthoracic echocardiography, electrocardiography (ECG), and serum cardiac markers at baseline and after 4 cycles of EC and 4 cycles of docetaxel. To evaluate the influence of interobserver variation, the QTc interval was analyzed by a cardiologist, a gynecologist, and with automated ECG interpretation software.

RESULTS

There was a significant QTc prolongation after EC treatment independent of the investigator. In addition, a significant increase in N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels was noted after EC treatment. QTc prolongation and NT-proBNP levels normalized after docetaxel treatment. Other biochemical markers were within normal ranges. No clinically relevant effect on left ventricular ejection fraction was observed.

CONCLUSION

This prospective study demonstrated that EC treatment increases the QTc interval and NT-proBNP levels in women with early breast cancer. This effect was reversible and independent of docetaxel administration. Moreover, the treating physician can safely perform QTc interval evaluation as part of clinical routine independent of his/her specialty. Due to the small number of patients, further conclusions are limited at this point.

Inframammary Fold Reconstruction: A Biomechanical Analysis

Background:

Inframammary fold reconstruction has scarcely been evaluated in literature. No biomechanical analyses have been performed comparing different reconstructive methods. This evaluation compares the gold-standard suture reconstruction with an intrarib anchor system (Micro BioComposite SutureTak, Arthrex).

Methods:

Three analysis groups were compared including 8 Sawbone blocks, 22 embalmed cadaver, and 27 regular cadaver specimens (N = 57). Transient mechanical analysis was performed at 5 N/s using an Instron 5565 test frame.

Results:

Ultimate load favored the anchor system (compared with the gold-standard suture) by a factor of 9.8 (P < 0.0001) for the regular cadaver group and a factor of 1.7 (P < 0.038) for the embalmed cadaver group. A similar statistically significant benefit was shown for stiffness and load at 2-mm displacement.

Conclusions:

This analysis showed an anchor system to be the biomechanically superior fixation method in terms of ultimate load, fixation stiffness, and displacement at failure when compared with the gold-standard suture method in inframammary fold reconstruction. Because of superior stability in every aspect, an anchor system may be considered for inframammary fold reconstruction.

Senology in Gynaecology Specialist Training: a Baseline Survey from 2014

Introduction: Qualified training in senology is essential for maintaining adequate, high quality patient care. In order to meet the needs of doctors in training and those of the medical infrastructure it is necessary to assess the quality of training regularly, to enable its adaption and optimisation. Methods: We developed a comprehensive, 10 item online questionnaire to assess the quality of specialised training in senology. This questionnaire was sent to 4000 speciality trainees and young specialists countrywide via the DGGG newsletter and was accessible for over four weeks. Results: 111 obstetrics and gynaecology speciality trainees participated in this national survey, 79 % of whom were female. 33 % of participants were working at university hospitals, 29 % at hospitals offering maximal level care without an associated medical faculty, 37 % at hospitals offering primary and secondary level care and 2 % at gynaecology practices. 25 % of participants could imagine working in the field of senology in future. On average the current perception of general specialist training was satisfactory. Specialist trainees at university hospitals rated training in senology highest (score: 2.95) compared to those at other hospitals. A fixed rotation through a breast centre offering comprehensive advanced training was seen as a potential improvement to senology training. Conclusions: This is the first survey of specialised training in senology to be conducted in Germany. Results showed that there is significant potential for young doctors to enter the speciality in future. There are also significant differences in the perceived quality of senology training between training facilities. This survey aimed to determine the quality of specialised training at senology centres and hopes to contribute to a sustainable improvement in training. The intention is to continue to make senology attractive to gynaecologists and to ensure well-grounded training.