Omission of Axillary Dissection Following Nodal Downstaging With Neoadjuvant Chemotherapy

Importance

Data on oncological outcomes after omission of axillary lymph node dissection (ALND) in patients with breast cancer that downstages from node positive to negative with neoadjuvant chemotherapy are sparse. Additionally, the best axillary surgical staging technique in this scenario is unknown.

Objective

To investigate oncological outcomes after sentinel lymph node biopsy (SLNB) with dual-tracer mapping or targeted axillary dissection (TAD), which combines SLNB with localization and retrieval of the clipped lymph node.

Design, Setting, and Participants

In this multicenter retrospective cohort study that was conducted at 25 centers in 11 countries, 1144 patients with consecutive stage II to III biopsy-proven node-positive breast cancer were included between April 2013 and December 2020. The cumulative incidence rates of axillary, locoregional, and any invasive (locoregional or distant) recurrence were determined by competing risk analysis.

Exposure

Omission of ALND after SLNB or TAD.

Main Outcomes and Measures

The primary end points were the 3-year and 5-year rates of any axillary recurrence. Secondary end points included locoregional recurrence, any invasive (locoregional and distant) recurrence, and the number of lymph nodes removed.

Results

A total of 1144 patients (median [IQR] age, 50 [41-59] years; 78 [6.8%] Asian, 105 [9.2%] Black, 102 [8.9%] Hispanic, and 816 [71.0%] White individuals; 666 SLNB [58.2%] and 478 TAD [41.8%]) were included. A total of 1060 patients (93%) had N1 disease, 619 (54%) had ERBB2 (formerly HER2)-positive illness, and 758 (66%) had a breast pathologic complete response. TAD patients were more likely to receive nodal radiation therapy (85% vs 78%; P = .01). The clipped node was successfully retrieved in 97% of TAD cases and 86% of SLNB cases (without localization). The mean (SD) number of sentinel lymph nodes retrieved was 3 (2) vs 4 (2) (P < .001), and the mean (SD) number of total lymph nodes removed was 3.95 (1.97) vs 4.44 (2.04) (P < .001) in the TAD and SLNB groups, respectively. The 5-year rates of any axillary, locoregional, and any invasive recurrence in the entire cohort were 1.0% (95% CI, 0.49%-2.0%), 2.7% (95% CI, 1.6%-4.1%), and 10% (95% CI, 8.3%-13%), respectively. The 3-year cumulative incidence of axillary recurrence did not differ between TAD and SLNB (0.5% vs 0.8%; P = .55).

Conclusions and Relevance

The results of this cohort study showed that axillary recurrence was rare in this setting and was not significantly lower after TAD vs SLNB. These results support omission of ALND in this population.

Trends in use of neoadjuvant systemic therapy in patients with clinically node-positive breast cancer in Europe: prospective TAXIS study (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

PURPOSE

The aim of this study was to evaluate clinical practice heterogeneity in use of neoadjuvant systemic therapy (NST) for patients with clinically node-positive breast cancer in Europe.

METHODS

The study was preplanned in the international multicenter phase-III OPBC-03/TAXIS trial (ClinicalTrials.gov Identifier: NCT03513614) to include the first 500 randomized patients with confirmed nodal disease at the time of surgery. The TAXIS study's pragmatic design allowed both the neoadjuvant and adjuvant setting according to the preferences of the local investigators who were encouraged to register eligible patients consecutively.

RESULTS

A total of 500 patients were included at 44 breast centers in six European countries from August 2018 to June 2022, 165 (33%) of whom underwent NST. Median age was 57 years (interquartile range [IQR], 48-69). Most patients were postmenopausal (68.4%) with grade 2 and 3 hormonal receptor-positive and human epidermal growth factor receptor 2-negative breast cancer with a median tumor size of 28 mm (IQR 20-40). The use of NST varied significantly across the countries (p < 0.001). Austria (55.2%) and Switzerland (35.8%) had the highest percentage of patients undergoing NST and Hungary (18.2%) the lowest. The administration of NST increased significantly over the years (OR 1.42; p < 0.001) and more than doubled from 20 to 46.7% between 2018 and 2022.

CONCLUSION

Substantial heterogeneity in the use of NST with HR+/HER2-breast cancer exists in Europe. While stringent guidelines are available for its use in triple-negative and HER2+ breast cancer, there is a need for the development of and adherence to well-defined recommendations for HR+/HER2-breast cancer.

A multicenter phase II trial of anti-EGFR-immunoliposomes loaded with doxorubicin in patients with advanced triple negative breast cancer

Advanced triple negative breast cancer (TNBC) is an aggressive, but initially chemo-sensitive disease. The prognosis is poor and more than three quarters of patients experience progression 12 months after the initiation of conventional first-line chemotherapy. Approximately two thirds of TNBC express epidermal growth factor receptor 1 (EGFR). We have developed an anti-EGFR targeted nanocontainer drug by inserting anti-EGFR antibody fragments into the membrane of pegylated liposomes (anti-EGFR-ILs-dox). The payload consists of doxorubicin, a standard drug for TNBC. In a first-in-human phase I trial in 26 patients with various advanced solid malignancies, anti-EGFR-ILs-dox has shown little toxicity and encouraging efficacy. In this single-arm phase II trial, we assessed the efficacy of anti-EGFR-ILs-dox as first-line therapy in patients with advanced, EGFR + TNBC. The primary endpoint was progression-free survival at 12 months (PFS12m). Secondary endpoints included overall response rate (ORR), duration of response (DOR), time to progression (TTP), overall survival (OS) and adverse events (AEs). 48 patients received anti-EGFR-ILs-dox 50 mg/m² iv, on day one of a 28 days-cycle until progression. The Kaplan-Meier estimate for PFS12m was 13% (one-sided 90% CI 7%, 95% CI [5%, 25%]), median PFS was 3.5 months (95% CI 1.9, 5.4). The trial has not reached its primary endpoint. There were no new toxicity signals. Based on these results, anti-EGFR-ILs-dox should not be further developed for TNBC. It remains an open question whether anti-EGFR-ILs-dox would offer more opportunities in other EGFR-expressing malignancies, where targeting this receptor has already shown anticancer effects.Trial registration: This trial was registered at clinicaltrials.gov: NCT02833766. Registered 14/07/2016.

Abstract P2-14-08: Trends in neoadjuvant systemic therapy rates in Europe: Pre-planned substudy of TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

Introduction: Even though randomized controlled trials could not show a significant survival benefit for the use of neoadjuvant systemic therapy (NST), it is increasingly recommended for patients with clinically node-positive breast cancer due to its implications on prognosis, locoregional downstaging and response-driven adjuvant systemic therapy. The aim of this study was to assess the need for international standardization of treatment recommendations by evaluating clinical practice heterogeneity in use of NST for patients with clinically node-positive breast cancer in Europe. Methods: The study was preplanned in the international multicenter phase-III OPBC-03/TAXIS trial (ClinicalTrials.gov Identifier: NCT03513614) after randomization of the first 500 patients with clinically node-positive breast cancer who underwent axillary lymph node dissection (ALND) or axillary radiation (ART) without ALND after tailored axillary surgery (TAS) in the context of extended regional nodal irradiation. Clinically node-positive breast cancer was defined by confirmed nodal disease at the time of initial diagnosis; in case of neoadjuvant therapy, residual nodal disease was mandatory. Investigators were encouraged to enroll all eligible patients consecutively. However, TAXIS is unique inasmuch as its pragmatic design allows both the neoadjuvant and adjuvant setting according to the preferences of the treating physicians and institutions and thus provides an excellent opportunity to study patterns and trends in use of NST in patients with clinically positive nodes in Europe. Results: A total of 500 patients with a median age of 57 years (IQR: 48-69 years) were included at 44 breast centers in 6 European countries from August 2018 to June 2022. Subtype was hormone receptor (HR) positive (+) and human epidermal growth factor receptor 2 (HER2) negative (-) in 393 (80.0%), HR+/HER2+ in 52 (10.6%), HR-/HER2+ in 5 (1.0%) and HR-/HER2- in 34 (6.9%) patients. The rate of patients undergoing NST was 31.4% with a significant upward trend over time during the study period (from 20.0% in 2018 to 38.1% in 2022; p=0.044). The use of NST varied significantly by country (p=&lt; 0.001) and by site (p=0.015). For patients with clinical AJCC tumor stage II and III, the rates of patients undergoing NST in Switzerland were 26.5% (18 of 68) and 35.9% (92 of 256), in Germany 22.2% (2 of 9) and 30.4% (7 of 23), in Austria 50% (7 of 14) and 60% (9 of 15) and in Hungary 0% (0 of 15) and 20.7% (18 of 87), respectively (p=0.019 and 0.004). Large differences by country were found for ER+/HER2- breast cancer, ranging from 13.1% (11 of 84) in Hungary to 47.8% (11 of 23) in Austria (p=0.007). Within Switzerland, which was the country with most included patients (328 of 500) and participating sites (n=25), the rate of patients undergoing NST for ER+/HER2- breast cancer varied considerably by site, ranging from 10% (2 of 20) to 50% (11 of 22). Discussion: This study revealed substantial heterogeneity in clinical practice in Europe, indicating the need for development of and adherence to consistent guidelines to standardize the international use of NST.

Citation Format: Walter P. Weber, Zoltan Matrai, Stefanie Hayoz, Guido Henke, Daniel R. Zwahlen, Günther Gruber, Frank Zimmermann, Thomas Ruhstaller, Simone Muenst, Markus Ackerknecht, Christian Kurzeder, Sherko Küemmel, Vesna Bjelic-Radisic, Viktor Smanykó, Conny Vrieling, Rok Satler, Inna Meyer, Charles Becciolini, Susanne Bucher, Colin Simonson, Peter M. Fehr, Natalie Gabriel, Robert Maráz, Dimitri Sarlos, Konstantin J. Dedes, Cornelia Leo, Gilles Berclaz, Hisham Fansa, Christopher Hager, Klaus Reisenberger, Ákos Sávolt, Christian F. Singer, Roland Reitsamer, Jelena Winkler, Giang Thanh Lam Lam, Mathias K. Fehr, Tatiana Naydina, Magdalena Kohlik, Karine Clerc, Valerijus Ostapenko, Florian Fitzal, Martin Heidinger, Nadia Maggi, Alexandra Schulz, Pagona Markellou, Loïc Lelièvre, Daniel Egle, Jörg Heil, Michael Knauer, Christoph Tausch. Trends in neoadjuvant systemic therapy rates in Europe: Pre-planned substudy of TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-14-08.

Abstract GS4-02: Oncological Outcomes Following Omission of Axillary Lymph Node Dissection in Node Positive Patients Downstaging To Node Negative with Neoadjuvant Chemotherapy: the OPBC-04/EUBREAST-06/OMA study

Background: Data on the oncologic safety of omission of axillary lymph node dissection (ALND) in node positive (N+) patients who downstage to ypN0 with neoadjuvant chemotherapy (NAC) is sparse. Additionally, there is no consensus on which axillary staging procedure should be used in this setting, sentinel lymph node biopsy (SLNB) alone or in combination with localization and retrieval of the clipped positive node, also known as targeted axillary dissection (TAD). Whether the reduction in the false negative rate observed with TAD translates into a significant reduction in the rate of axillary recurrence is unknown. We sought to evaluate oncologic outcomes after omission of ALND in a large, real-world cohort of breast cancer (BC) patients and to compare rates of axillary recurrence after SLNB with dual tracer mapping vs. TAD.

Methods: Data were collected from 19 centers in the Oncoplastic Breast Consortium (OPBC) and EUBREAST networks. Patients with T1-4 biopsy-proven N1-3 BC who underwent NAC followed by axillary staging with either SLNB with dual tracer mapping or TAD and who were pathologically node negative (ypN0) were included. ypN0 was defined as the absence of any tumor or isolated tumor cells. Competing risk analysis was performed to assess the cumulative incidence rates of axillary recurrence, locoregional recurrence, and any invasive (locoregional or distant) recurrence. Two-year cumulative incidence rates were compared between TAD and SLNB using the Gray’s test. Type I error rate was set to 0.05 (α).

Results: We included 785 patients (565 treated with SLNB and 220 with TAD) treated with NAC followed by surgery from 01/2014-12/2020. Median patient age was 50 years. The majority (57%) of patients had clinical T2 tumors, and 95% had N1 disease. Most (55%) were HER2+, and 21% were triple negative. Most patients (81%) received anthracycline and taxane-based chemotherapy regimens, but NAC regimens differed between patients treated with TAD and those treated with SLNB (Table 1). All patients with HER2+ tumors received anti HER2 therapy. Nodal radiotherapy was administered to 76% of patients, and was more common in patients who underwent TAD (82% TAD vs 74% SLNB, p=0.017). Breast pathologic complete response (ypT0/is) was more frequent among those patients that had TAD (80% TAD vs. 66% SLNB, p&lt; 0.001). TAD localization was with wire in 46%, radioactive seed in 40%, ultrasound in 5%, tattoo in 2%, and with a combination of these techniques in 7%. The clipped node was successfully retrieved in 94% of TAD cases. The median number of lymph nodes removed was lower in the TAD group compared to the SLNB group [3 (IQR 3-5) vs 4 IQR 3-5), p&lt; 0.001], as was the median number of sentinel lymph nodes [3 (IQR 2-4) vs 4 IQR 3-5), p&lt; 0.001] (Table 1). The 5-year rates of any axillary recurrence, locoregional recurrence, and any invasive recurrence in the entire cohort were 1.1% (95%CI 0.39-2.4%), 3.1% (95%CI 1.6-5.3%) and 10% (95%CI 7.6-13%), respectively. The two-year cumulative incidence of axillary recurrence did not differ between patients treated with TAD compared to SLNB (0% vs 0.9%, p=0.19).

Conclusion: Early axillary recurrence after omission of ALND in patients who successfully downstage from N+ to ypN0 with NAC is a rare event following both SLNB or TAD, and was not significantly lower in TAD than SLNB. Although longer follow-up is needed to confirm these findings, the main advantage of TAD seems to be a reduction in the number of lymph nodes removed. Overall, these results support omission of ALND in patients who successfully downstage to node negative disease after NAC.

Table 1: Clinicopathological Features of the Study Cohort, Stratified by Axillary Staging Technique

Citation Format: Giacomo Montagna, Mary Mrdutt, Astrid Botty, Andrea V. Barrio, Varadan Sevilimedu, Judy C. Boughey, Tanya L. Hoskin, Laura H. Rosenberger, E Shelley Hwang, Abigail Ingham, Bärbel Papassotiropoulos, Bich Doan Nguyen-Sträuli, Christian Kurzeder, Danilo Diaz Aybar, Denise Vorburger, Dieter Michael Matlac, Edvin Ostapenko, Fabian Riedel, Florian Fitzal, Francesco Meani, Franziska Fick, Jacqueline Sagasser, Jörg Heil, Konstantin J. Dedes, Laszlo Romics, Maggie Banys-Paluchowski, Maria Del Rosario Cueva Perez, Marcelo Chavez Diaz, Martin Heidinger, Mathias K. Fehr, Mattea Reinisch, Nadia Maggi, Nicola Rocco, Nina Ditsch, Oreste Davide Gentilini, Regis Resende Paulinelli, Sebastian Sole Zarhi, Sherko Küemmel, Simona Bruzas, Simona Di Lascio, Tamara Parissenti, Uwe Güth, Valentina Ovalle, Christoph Tausch, Monica Morrow, Thorsten Kühn, Walter P. Weber. Oncological Outcomes Following Omission of Axillary Lymph Node Dissection in Node Positive Patients Downstaging To Node Negative with Neoadjuvant Chemotherapy: the OPBC-04/EUBREAST-06/OMA study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS4-02.

Contrast Media-Enhanced Breast Computed Tomography With a Photon-Counting Detector: Initial Experiences on In Vivo Image Quality and Correlation to Histology

OBJECTIVES

The aim of this study was to investigate the feasibility, the image quality, and the correlation with histology of dedicated spiral breast computed tomography (B-CT) equipped with a photon-counting detector in patients with suspicious breast lesions after application of iodinated contrast media.

MATERIALS AND METHODS

The local ethics committee approved this prospective study. Twelve women with suspicious breast lesions found in mammography or B-CT underwent contrast-enhanced spiral B-CT and supplementary ultrasound. For all lesions, biopsy-proven diagnosis and histological workup after surgical resection were obtained including the size of cancer/ductal carcinoma in situ, which were correlated to sizes measured in B-CT. Signal-to-noise ratio and contrast-to-noise ratio were evaluated for tumor, glandular tissue, and fatty tissue.

RESULTS

Of the 12 patients, 15 suspicious lesions were found, 14 were malignant, and 1 benign lesion corresponded to a chronic inflammation. All lesions showed strong contrast media uptake with a signal-to-noise ratio of 119.7 ± 52.5 with a contrast-to-noise ratio between glandular tissue and breast cancer lesion of 12.6 ± 5.9. The correlation of the size of invasive tumors measured in B-CT compared with histological size was significant and strong R = 0.77 ( P < 0.05), whereas the correlation with the size of the peritumoral ductal carcinoma in situ was not significant R = 0.80 ( P = 0.11).

CONCLUSIONS

Contrast-enhanced B-CT shows high contrast between breast cancer and surrounding glandular tissue; therefore, it is a promising technique for cancer detection and staging depicting both soft tissue lesions and microcalcifications, which might be a substantial advantage over breast MRI.

Single-incision for breast-conserving surgery through round block technique

AIMS AND OBJECTIVES

The purpose of this study was to assess the feasibility of using the single-incision round block technique in breast-conserving surgery with sentinel lymph node (SLN) retrieval for breast cancer without compromising oncological safety.

MATERIALS AND METHODS

A retrospective observational case-control study was conducted from January 2017 to October 2021. The study population consisted of two groups. In both groups, breast-conserving surgery was carried out through the round-block technique. In group A, SLN retrieval was performed using the round-block incision (study group), while in group B, SLN retrieval was conducted through a second skin incision in the axilla (control group). The study was approved by the local ethics committee Zurich (BASEC-Nr. 2020-02857), and written informed consent was obtained from all participants.

RESULTS

Overall, 134 patients met the inclusion criteria, of whom 86 women underwent breast-conserving surgery and SLN retrieval using the single-incision approach (group A), and 48 women underwent conventional surgery, using two independent incisions for tumour resection and SLN retrieval (group B). The overall success rate in group A regarding SLN retrieval was 97.7%, whereas most tumours were located in the upper outer (47.7%) and upper inner quadrant (27.9%). Although the technique was equally successful in the other quadrants, the share of tumours in the lower outer, and the lower inner quadrant, and the retroareolar region was smaller, representing 17.4%, 3.5% and 3.5%, respectively. The median number of dissected lymph nodes was two, with a positivity rate of 24.4%. The occurrence of axillary neuralgia and axillary skin retraction was significantly higher in group B along with tendentially more axillary seroma formation. There were no significant differences regarding reintervention rates, in terms of complications, resection margins, locoregional recurrences, or deaths with a mean follow-up of 11 months.

CONCLUSIONS

The single-incision method through the round block technique is as safe and effective as the standard two-incision approach regarding nodal staging and resection margins, and seems to be applicable for tumours in all breast quadrants.

Setting a diagnostic benchmark for tumor BRCA testing: detection of BRCA1 and BRCA2 large genomic rearrangements in FFPE tissue - A pilot study

PARP inhibitors are used for treatment of tumors lacking function of the double-strand DNA break repair proteins BRCA1 or BRCA2 and are already approved for several cancer types. Thus, it is clinically crucial to determine germline as well as somatic BRCA1/2 mutations in those patients. The amplicon-based Oncomine BRCA1 and BRCA2 Assay is a test routinely used in diagnostics with FFPE specimens. The assay is validated for the detection of mutations, however, data on its performance in detecting large genomic rearrangements in FFPE tissue, is scarce. We cross-validated Oncomine BRCA1 and BRCA2 Assay in blood samples and/or FFPE tissue with multiplex ligation-dependent probe amplification (MLPA) for exon deletions and with OncoScan and an in-house hybridization-based target capture assay (MelArray) with a customized pipeline for the detection of loss of heterozygosity (LOH) and heterozygous versus complete gene loss. The Oncomine BRCA1 and BRCA2 Assay could detect both exon deletion and mono- and bi-allelic losses of the BRCA1/2 genes. We show that the therapeutically relevant large genomic rearrangements are reliably detected with the amplicon-based Oncomine BRCA1 and BRCA2 Assay in FFPE tumor tissue. Based on our data, we suggest tumor BRCA testing as standard diagnostic prescreening prior to germline BRCA testing.

Tailored axillary surgery in patients with clinically node-positive breast cancer: Pre-planned feasibility substudy of TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

Aim

We developed tailored axillary surgery (TAS) to reduce the axillary tumor volume in patients with clinically node-positive breast cancer to the point where radiotherapy can control it. The aim of this study was to quantify the extent of tumor load reduction achieved by TAS.

Methods

International multicenter prospective study embedded in a randomized trial. TAS is a novel pragmatic concept for axillary surgery de-escalation that combines palpation-guided removal of suspicious nodes with the sentinel procedure and, optionally, imaging-guided localization. Pre-specified study endpoints quantified surgical extent and reduction of tumor load.

Results

A total of 296 patients were included at 28 sites in four European countries, 125 (42.2%) of whom underwent neoadjuvant chemotherapy (NACT) and 71 (24.0%) achieved nodal pathologic complete response. Axillary metastases were detectable only by imaging in 145 (49.0%) patients. They were palpable in 151 (51.0%) patients, of whom 63 underwent NACT and 21 had residual palpable disease after NACT. TAS removed the biopsied and clipped node in 279 (94.3%) patients. In 225 patients with nodal disease at the time of surgery, TAS removed a median of five (IQR 3–7) nodes, two (IQR 1–4) of which were positive. Of these 225 patients, 100 underwent ALND after TAS, which removed a median of 14 (IQR 10–17) additional nodes and revealed additional positive nodes in 70/100 (70%) of patients. False-negative rate of TAS in patients who underwent subsequent ALND was 2.6%.

Conclusions

TAS selectively reduced the tumor load in the axilla and remained much less radical than ALND.

•

Tailored axillary surgery is a novel concept for clinically node-positive breast cancer

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Tailored axillary surgery selectively removes positive lymph nodes

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Tailored axillary surgery is much less radical than axillary dissection

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Tailored axillary surgery removes the clipped node in the vast majority of patients

New clinical and biological insights from the international TARGIT-A randomised trial of targeted intraoperative radiotherapy during lumpectomy for breast cancer

BACKGROUND

The TARGIT-A trial reported risk-adapted targeted intraoperative radiotherapy (TARGIT-IORT) during lumpectomy for breast cancer to be as effective as whole-breast external beam radiotherapy (EBRT). Here, we present further detailed analyses.

METHODS

In total, 2298 women (≥45 years, invasive ductal carcinoma ≤3.5 cm, cN0-N1) were randomised. We investigated the impact of tumour size, grade, ER, PgR, HER2 and lymph node status on local recurrence-free survival, and of local recurrence on distant relapse and mortality. We analysed the predictive factors for recommending supplemental EBRT after TARGIT-IORT as part of the risk-adapted approach, using regression modelling. Non-breast cancer mortality was compared between TARGIT-IORT plus EBRT vs. EBRT.

RESULTS

Local recurrence-free survival was no different between TARGIT-IORT and EBRT, in every tumour subgroup. Unlike in the EBRT arm, local recurrence in the TARGIT-IORT arm was not a predictor of a higher risk of distant relapse or death. Our new predictive tool for recommending supplemental EBRT after TARGIT-IORT is at https://targit.org.uk/addrt . Non-breast cancer mortality was significantly lower in the TARGIT-IORT arm, even when patients received supplemental EBRT, HR 0.38 (95% CI 0.17-0.88) P = 0.0091.

CONCLUSION

TARGIT-IORT is as effective as EBRT in all subgroups. Local recurrence after TARGIT-IORT, unlike after EBRT, has a good prognosis. TARGIT-IORT might have a beneficial abscopal effect.

TRIAL REGISTRATION

ISRCTN34086741 (21/7/2004), NCT00983684 (24/9/2009).

Ectopic axillary breast cancer in a male patient

Ectopic breast tissue can persist in the axilla due to lack of involution of mammary glands along the mammary lines. It is rare in men, and the malignant transformation to breast cancer has occasionally been described. Differential diagnosis of any axillary tumor should include breast cancer arising at ectopic sites.

Long term survival and local control outcomes from single dose targeted intraoperative radiotherapy during lumpectomy (TARGIT-IORT) for early breast cancer: TARGIT-A randomised clinical trial

OBJECTIVE

To determine whether risk adapted intraoperative radiotherapy, delivered as a single dose during lumpectomy, can effectively replace postoperative whole breast external beam radiotherapy for early breast cancer.

DESIGN

Prospective, open label, randomised controlled clinical trial.

SETTING

32 centres in 10 countries in the United Kingdom, Europe, Australia, the United States, and Canada.

PARTICIPANTS

2298 women aged 45 years and older with invasive ductal carcinoma up to 3.5 cm in size, cN0-N1, eligible for breast conservation and randomised before lumpectomy (1:1 ratio, blocks stratified by centre) to either risk adapted targeted intraoperative radiotherapy (TARGIT-IORT) or external beam radiotherapy (EBRT).

INTERVENTIONS

Random allocation was to the EBRT arm, which consisted of a standard daily fractionated course (three to six weeks) of whole breast radiotherapy, or the TARGIT-IORT arm. TARGIT-IORT was given immediately after lumpectomy under the same anaesthetic and was the only radiotherapy for most patients (around 80%). TARGIT-IORT was supplemented by EBRT when postoperative histopathology found unsuspected higher risk factors (around 20% of patients).

MAIN OUTCOME MEASURES

Non-inferiority with a margin of 2.5% for the absolute difference between the five year local recurrence rates of the two arms, and long term survival outcomes.

RESULTS

Between 24 March 2000 and 25 June 2012, 1140 patients were randomised to TARGIT-IORT and 1158 to EBRT. TARGIT-IORT was non-inferior to EBRT: the local recurrence risk at five year complete follow-up was 2.11% for TARGIT-IORT compared with 0.95% for EBRT (difference 1.16%, 90% confidence interval 0.32 to 1.99). In the first five years, 13 additional local recurrences were reported (24/1140 v 11/1158) but 14 fewer deaths (42/1140 v 56/1158) for TARGIT-IORT compared with EBRT. With long term follow-up (median 8.6 years, maximum 18.90 years, interquartile range 7.0-10.6) no statistically significant difference was found for local recurrence-free survival (hazard ratio 1.13, 95% confidence interval 0.91 to 1.41, P=0.28), mastectomy-free survival (0.96, 0.78 to 1.19, P=0.74), distant disease-free survival (0.88, 0.69 to 1.12, P=0.30), overall survival (0.82, 0.63 to 1.05, P=0.13), and breast cancer mortality (1.12, 0.78 to 1.60, P=0.54). Mortality from other causes was significantly lower (0.59, 0.40 to 0.86, P=0.005).

CONCLUSION

For patients with early breast cancer who met our trial selection criteria, risk adapted immediate single dose TARGIT-IORT during lumpectomy was an effective alternative to EBRT, with comparable long term efficacy for cancer control and lower non-breast cancer mortality. TARGIT-IORT should be discussed with eligible patients when breast conserving surgery is planned.

TRIAL REGISTRATION

ISRCTN34086741, NCT00983684.

Effect of Delayed Targeted Intraoperative Radiotherapy vs Whole-Breast Radiotherapy on Local Recurrence and Survival: Long-term Results From the TARGIT-A Randomized Clinical Trial in Early Breast Cancer

Importance

Conventional adjuvant radiotherapy for breast cancer given daily for several weeks is onerous and expensive. Some patients may be obliged to choose a mastectomy instead, and some may forgo radiotherapy altogether. We proposed a clinical trial to test whether radiotherapy could be safely limited to the tumor bed.

Objective

To determine whether delayed second-procedure targeted intraoperative radiotherapy (TARGIT-IORT) is noninferior to whole-breast external beam radiotherapy (EBRT) in terms of local control.

Design, Setting, and Participants

In this prospective, randomized (1:1 ratio) noninferiority trial, 1153 patients aged 45 years or older with invasive ductal breast carcinoma smaller than 3.5 cm treated with breast conservation were enrolled from 28 centers in 9 countries. Data were locked in on July 3, 2019.

Interventions

The TARGIT-A trial was started in March 2000; patients were randomized after needle biopsy to receive TARGIT-IORT immediately after lumpectomy under the same anesthetic vs EBRT and results have been shown to be noninferior. A parallel study, described in this article, was initiated in 2004; patients who had their cancer excised were randomly allocated using separate randomization tables to receive EBRT or delayed TARGIT-IORT given as a second procedure by reopening the lumpectomy wound.

Main Outcomes and Measures

A noninferiority margin for local recurrence rate of 2.5% at 5 years, and long-term survival outcomes.

Results

Overall, 581 women (mean [SD] age, 63 [7] years) were randomized to delayed TARGIT-IORT and 572 patients (mean [SD] age, 63 [8] years) were randomized to EBRT. Sixty patients (5%) had tumors larger than 2 cm, or had positive nodes and only 32 (2.7%) were younger than 50 years. Delayed TARGIT-IORT was not noninferior to EBRT. The local recurrence rates at 5-year complete follow-up were: delayed TARGIT-IORT vs EBRT (23/581 [3.96%] vs 6/572 [1.05%], respectively; difference, 2.91%; upper 90% CI, 4.4%). With long-term follow-up (median [IQR], 9.0 [7.5-10.5] years), there was no statistically significant difference in local recurrence-free survival (HR, 0.75; 95% CI, 0.57-1.003; P = .052), mastectomy-free survival (HR, 0.88; 95% CI, 0.65-1.18; P = .38), distant disease-free survival (HR, 1.00; 95% CI, 0.72-1.39; P = .98), or overall survival (HR, 0.96; 95% CI, 0.68-1.35; P = .80).

Conclusions and Relevance

These long-term data show that despite an increase in the number of local recurrences with delayed TARGIT-IORT, there was no statistically significant decrease in mastectomy-free survival, distant disease-free survival, or overall survival.

Trial Registration

ISRCTN34086741, ClinicalTrials.gov Identifier: NCT00983684.

A cost-effectiveness analysis of consolidation immunotherapy with durvalumab in stage III NSCLC responding to definitive radiochemotherapy in Switzerland

BACKGROUND

Consolidation immunotherapy with the programmed death ligand 1 (PD-L1) inhibitor durvalumab improves survival in patients with stage III non-small-cell lung cancer responding to radiochemotherapy. The aim of this study was to assess the cost-effectiveness of durvalumab in Switzerland based on the most recent PACIFIC survival follow-up.

MATERIALS AND METHODS

We constructed a Markov model based on the 3-year follow-up data of the PACIFIC trial and compared consolidation durvalumab with observation. We used published utility values and assessed costs for treatment strategies from the perspective of the Swiss health care payers. Cost-effectiveness was tested both in the intention-to-treat population of the PACIFIC trial unselected for PD-L1 tumor expression and in patients with PD-L1-expressing tumors (≥1%).

RESULTS

In the unselected/PD-L1-positive patients, durvalumab showed an incremental effectiveness of 0.76/1.18 quality-adjusted life year (QALY) and incremental costs of Swiss Francs (CHF) 67 239/78 177, resulting in incremental cost-effectiveness ratios of CHF 88 703/66 131 per QALY gained, respectively. The most influential factors for the incremental cost-effectiveness ratio were the utility before first progression, costs for durvalumab, and the hazard ratio for overall survival under durvalumab versus observation. The cost-effectiveness of durvalumab was better than CHF 100 000 per QALY gained in 75% of the simulations in probabilistic sensitivity analysis.

CONCLUSION

Assuming a willingness-to-pay threshold of CHF 100 000 per QALY gained, consolidation durvalumab is likely to be cost-effective both in patients with inoperable stage III non-small-cell lung cancer (NSCLC) unselected for PD-L1 status and in patients with PD-L1-expressing tumors in Switzerland.

[Rare Forms of Mastitis]

Rare Forms of Mastitis Abstract. Inflammatory breast diseases caused by bacterial infections represent the main cause for mastitis in breastfeeding and non-breastfeeding women. The clinical appearance and a standardized evaluation can indicate rare inflammatory breast diseases. An underlying comorbidity or the evidence of rare pathogens could be suggestive. However, core needle biopsy is the main step in diagnostics. Malignancy, e.g. an inflammatory breast cancer must consistently be excluded. This mini review outlines a few rare inflammatory breast diseases, their initial presentation, and how to diagnose them accurately.

Loss of MDC1 in Endometrial Carcinoma Is Associated With Loss of MRN Complex and MMR Deficiency

AIM

To evaluate the frequency of loss of mediator of DNA damage checkpoint protein 1 (MDC1) protein expression in endometrial cancer (EC) and to determine whether loss of MDC1 is associated with certain clinicopathological parameters.

MATERIALS AND METHODS

MDC1 expression was examined in 426 samples of EC. The nuclear immunoreactivity of the protein was defined as: negative, weak, moderate and strong.

RESULTS

Loss of MDC1 expression (defined as negative nuclear staining) was found in 8.9% (38/426) of ECs and was significantly associated with the loss of MRE11 homolog, double-strand break repair nuclease, RAD50 double-strand break repair protein and nibrin complex components. In addition, loss of expression of MDC1 showed a significant correlation with any mismatch repair deficiency, with endometrioid histological subtype and low tumour grading.

CONCLUSION

Based on these findings, we suggest that MDC1 loss frequently occurs in ECs with microsatellite instability. Due to deficient homologous recombination DNA repair, MDC1-negative ECs might show an increased sensitivity to poly(ADP-ribose) polymerase-inhibitory therapy.

Prevalence of genetic susceptibility for breast and ovarian cancer in a non-cancer related study population: secondary germline findings from a Swiss single centre cohort

BACKGROUND

Since the advent of high-throughput sequencing technologies, organised germline screening, independent of the personal and family cancer history, has been frequently proposed. Since ethnic and geographic populations significantly differ in their mutation spectra and prevalence, one critical prerequisite would be the knowledge of the expected carrier frequencies.

OBJECTIVE

For the first time, in a retrospective non-cancer related cohort from a single Swiss genetic centre, we systematically assessed the prevalence of secondary findings in 19 genes (BRCA1/2 plus 17 non-BRCA genes) previously designated by the US National Comprehensive Cancer Network (NCCN) for hereditary breast and ovarian cancer (HBOC) germline testing.

DESIGN

A total of 400 individuals without a cancer diagnosis undergoing whole-exome sequencing (WES) analysis for neurodevelopmental disorders (NDDs) from 2015 to 2017 at IMG Zurich were included after quality assessment. Among these, 180 were unaffected parental couples, 27 unaffected parental singles and 13 NDD index patients (mean age 43 years). The majority of the cohort was of Caucasian ethnicity (n = 336, 84.0%) and of Northwest European ancestry (n = 202, 50.5%), for 70 of whom (42.5%) an autochthonous Swiss descent was assumed. For WES filtering of rare, potentially actionable secondary variants in HBOC genes, an overall minor allele frequency (MAF) below 0.65% was used as cut-off. Each rare variant was manually evaluated according to the recommended ACGM-AMP standards, with some adaptations including &ldquo;hypomorphic&rdquo; as an additional distinct pathogenicity class.

RESULTS

Overall, 526 rare secondary variants (339 different variants) were encountered, with the BRCA1/2 genes accounting for 27.2% of the total variant yield. If stratified for variant pathogenicity, for BRCA1/2, three pathogenic variants were found in three females of Italian ancestry (carrier frequency of 0.8%). In the non-BRCA genes, five carriers of (likely) pathogenic variants (1.3%) were identified, with two Swiss individuals harbouring the same CHEK2 Arg160Gly variant known to be recurrent among Caucasians. Hence, the overall carrier rate added up to 2.0%. Additionally, seven various hypomorphic HBOC predisposing alleles were detected in 22 individuals (5.5%).

CONCLUSION

We provide the first evidence of a high prevalence of HBOC-related cancer susceptibility in the heterogeneous Swiss general population and relevant subpopulations, particularly in individuals of Italian descent. These pioneering data may substantiate population-based HBOC screening in Switzerland.

A cost-effectiveness analysis of consolidative local therapy in oligometastatic non-squamous non-small cell lung cancer (NSCLC)

BACKGROUND

Novel systemic therapies have improved the prognosis of metastatic non-small cell lung cancer (NSCLC), but costs of some of these drugs are a matter of ongoing debate. More recently, local therapies (LT) such as radiotherapy and surgery have been suggested as additional treatment in oligometastatic NSCLC demonstrating an improved progression-free survival (PFS) in a phase II trial compared to maintenance chemotherapy (MC) alone. The aim of this analysis was to assess the cost-effectiveness of local therapies in oligometastatic NSCLC.

METHODS

We constructed a Markov model comparing the cost-effectiveness of LT versus MC for oligometastatic NSCLC from the Swiss healthcare payer's perspective. Treatment specifications and PFS were based on the phase II trial (NCT01725165). Overall survival (OS) was inferred from a recent phase III trial. Utilities were taken from published data. Primary outcome was the incremental cost-effectiveness-ratio (ICER, costs in Swiss Francs (CHF) per quality-adjusted life-year (QALY) gained).

RESULTS

PFS in the model was 3.8 months for MC and 11.4 months for LT (compared to 3.9 months and 11.9 months in the trial). OS in the model was 15.5 months in both arms. LT was cost-effective with a gain of 0.24 QALYs at an additional cost of CHF 9641, resulting in an ICER of CHF 40,972/QALY gained. Probabilistic sensitivity analyses demonstrated that LT was dominant or cost-effective at a willingness-to-pay threshold of CHF 100,000 per QALY in 61.7% of the simulations.

CONCLUSIONS

LT may be cost-effective for selected patients with oligometastatic NSCLC responding to first-line systemic therapy.

Feasibility of 18F-FDG Dose Reductions in Breast Cancer PET/MRI

The goal of this study was to determine the level of clinically acceptable ¹⁸F-FDG dose reduction in time-of-flight PET/MRI in patients with breast cancer. Methods: Twenty-six consecutive women with histologically proven breast cancer were analyzed (median age, 51 y; range, 34-83 y). Simulated dose-reduced PET images were generated by unlisting the list-mode data on PET/MRI. The acquired 20-min PET frame was reconstructed in 5 ways: a reconstruction of the first 2 min with 3 iterations and 28 subsets for reference, and reconstructions simulating 100%, 20%, 10%, and 5% of the original dose. General image quality and artifacts, image sharpness, image noise, and lesion detectability were analyzed using a 4-point scale. Qualitative parameters were compared using the nonparametric Friedman test for multiple samples and the Wilcoxon signed-rank test for paired samples. Different groups of independent samples were compared using the Mann-Whitney U test. Results: Overall, 355 lesions (71 lesions with 5 different reconstructions each) were evaluated. The 20-min reconstruction with 100% injected dose showed the best results in all categories. For general image quality and artifacts, image sharpness, and noise, the reconstructions with a simulated dose of 20% and 10% were significantly better than the 2-min reconstructions (P ≤ 0.001). Furthermore, 20%, 10%, and 5% reconstructions did not yield results different from those of the 2-min reconstruction for detectability of the primary lesion. For 10% of the injected dose, a calculated mean dose of 22.6 ± 5.5 MBq (range, 17.9-36.9 MBq) would have been applied, resulting in an estimated whole-body radiation burden of 0.5 ± 0.1 mSv (range, 0.4-0.7 mSv). Conclusion: Ten percent of the standard dose of ¹⁸F-FDG (reduction of ≤90%) results in clinically acceptable PET image quality in time-of-flight PET/MRI. The calculated radiation exposure would be comparable to the effective dose of a single digital mammogram. A reduction of radiation burden to this level might justify partial-body examinations with PET/MRI for dedicated indications.

Preclinical evaluation of the PARP inhibitor BMN-673 for the treatment of ovarian clear cell cancer

Purpose

To determine if models of ovarian clear cell carcinomas (OCCCs) harbouring defects in homologous recombination (HR) DNA repair of double strand breaks (DSBs) are sensitive to cisplatin and/or PARP inhibition.

Experimental Design

The HR status of 12 OCCC cell lines was determined using RAD51/γH2AX foci formation assays. Sensitivity to cisplatin and the PARP inhibitor BMN-673 was correlated with HR status. BRCA1, BRCA2, MRE11 and PTEN loss of expression was investigated as a potential determinant of BMN-673 sensitivity. A tissue microarray containing 50 consecutive primary OCCC was assessed for PTEN expression using immunohistochemistry.

Results

A subset of OCCC cells displayed reduced RAD51 foci formation in the presence of DNA DSBs, suggestive of HR defects. HR-defective OCCC cells, with the exception of KOC-7c, had higher sensitivity to cisplatin/ BMN-673 than HR-competent OCCC cell lines (Log10 SF50 –9.4 (SD +/− 0.29) vs –8.1 (SD +/− 0.35), mean difference 1.3, p < 0.01). Of the cell lines studied, two, TOV-21G and KOC-7c, showed loss of PTEN expression. In primary OCCCs, loss of PTEN expression was observed in 10% (5/49) of cases.

Conclusions

A subset of OCCC cells are sensitive to PARP inhibition in vitro, which can be predicted by HR defects as defined by γH2AX/RAD51 foci formation. These results provide a rationale for the testing of HR deficiency and PARP inhibitors as a targeted therapy in a subset of OCCCs.

Tissue Factor Expression Does Not Predict Mortality in Breast Cancer Patients

BACKGROUND

Tissue factor (TF), the trigger of coagulation, not only initiates thrombus formation, but also elicits tumor growth and invasion in breast cancer. However, the characterization of TF expression in breast cancer tissue and its prognostic value remain unclear.

MATERIALS AND METHODS

Three hundred and three primary breast cancer specimens from the local tumor tissue database were immunostained for TF expression and evaluated semiquantitatively. Tumor characteristics (size, grade, nodal status, and ER expression) as well as patient's survival were assessed.

RESULTS

Expression of TF was detected in 99% of specimens with higher expression in invasive lobular than ductal carcinoma (p=0.008). TF expression correlated with ER expression (p<0.0001) and inversely with tumor grade (p=0.006). Survival analysis did not reveal any prognostic impact of TF expression (p=0.966).

CONCLUSION

This study - by analyzing TF expression in the largest cohort of breast cancer patients so far - does not support a prognostic impact of TF expression.

Adjuvant treatment recommendations for patients with ER-positive/HER2-negative early breast cancer by Swiss tumor boards using the 21-gene recurrence score (SAKK 26/10)

Background

To evaluate the effect of Recurrence Score® results (RS; Oncotype DX® multigene assay ODX) on treatment recommendations by Swiss multidisciplinary tumor boards (TB).

Methods

SAKK 26/10 is a multicenter, prospective cohort study of early breast cancer patients: Eligibility: R0-resection, ≥10% ER+ malignant cells, HER2–, pN0/pN1a. Patients were stratified into low-risk (LR) and non-low-risk (NLR) groups based on involved nodes (0 vs 1–3) and five additional predefined risk factors. Recommendations were classified as hormonal therapy (HT) or chemotherapy plus HT (CT + HT). Investigators were blinded to the statistical analysis plan. A 5%/10% rate of recommendation change in LR/NLR groups, respectively, was assumed independently of RS (null hypotheses).

Results

Two hundred twenty two evaluable patients from 18 centers had TB recommendations before and after consideration of the RS result. A recommendation change occurred in 45 patients (23/154 (15%, 95% CI 10–22%) in the LR group and 22/68 (32%, 95% CI 22–45%) in the NLR group). In both groups the null hypothesis could be rejected (both p < 0.001). Specifically, in the LR group, only 5/113 (4%, 95% CI 1–10%) with HT had a recommendation change to CT + HT after consideration of the RS, while 18/41 (44%, 95% CI 28–60%) of patients initially recommended CT + HT were subsequently recommended only HT. In the NLR group, 3/19 (16%, 95% CI 3–40%) patients were changed from HT to CT + HT, while 19/48 (40%, 95% CI 26–55%) were changed from CT + HT to HT.

Conclusion

There was a significant impact of using the RS in the LR and the NLR group but only 4% of LR patients initially considered for HT had a recommendation change (RC); therefore these patients could forgo ODX testing. A RC was more likely for NLR patients considered for HT. Patients considered for HT + CT have the highest likelihood of a RC based on RS.

First ultrasound diagnosis of BI-RADS 3 lesions in young patients: Can 6-months follow-up be sufficient to assess stability?

OBJECTIVES

To evaluate the outcome of repeated short-term follow-up with ultrasound in no high-risk young patients with a BI-RADS3 lesion at first examination.

METHODS

In this IRB-approved study 492 women, aged 18-34 years (mean±standard deviation, 28±4.5years) with first breast ultrasound examination in 2012-2014 were retrospectively evaluated. Inclusion criteria were: at least one BI-RADS3 lesion and (a) biopsy/surgical excision or (b) follow-up of at least 18 months (including a 6-month follow-up). BI-RADS category assigned during follow-up and pathologic findings in cases undergoing biopsy/surgical excision were collected. At the 6- and 18-month follow-up the recommended biopsy rates (RBR) and the corresponding positive predictive value (PPV) were calculated.

RESULTS

In 97 patients, 151 BI-RADS3 lesions were identified. Biopsy/surgical excision was initially performed in 25/151 (16.5%) lesions. After 6-month, category was downgraded to BI-RADS1/2 in 23/126 (15.3%) and upgraded to BI-RADS4 in 9/126 lesions (7.1%). Pathological diagnosis of these lesions was fibroadenoma in 5 and benign phyllodes tumor in 4 cases (RBR 7%, PPV_bio 44.4%). After 18-month one lesion was classified BI-RADS4 and pathological diagnosis was fibroadenoma (RBR 1.1%, PPV_bio 0%).

CONCLUSIONS

Our preliminary data show that follow-up imaging performed after 18 months from a first BI-RADS3 diagnosis does not affect clinical treatment and 6-month follow-up may be sufficient to assess the stability of probably benign lesions.

A Micro CT Study in Patients with Breast Microcalcifications Using a Mathematical Algorithm to Assess 3D Structure

PURPOSE

The aim of this study was to evaluate the relevance of the three-dimensional (3D) structure of breast microcalcifications (MC) as a predictor of malignancy using highly resolved micro-computed tomography (micro-CT) datasets of biopsy samples.

MATERIAL AND METHODS

The study included 28 women with suspicious MC in their mammogram undergoing vacuum-assisted biopsy. Directly after the intervention, the specimens were scanned in a micro-CT with an isometric spatial resolution of 9 μm. Datasets were analysed regarding the number, volume and morphology of suspicious non-monomorphic MC (fl-fine linear, fp-fine pleomorphic, ch-coarse heterogeneous) and the structure model index (SMI). Histological evaluation was performed according to the B-classification: normal tissue or benign (group A: B1, B2), unclear malignant potential or suspicious of malignancy (group B: B3, B4) and malignant lesions (group C: B5).

RESULTS

In all groups, suspicious non-monomorphic MC were found: group A exhibited fp MC in 38.5% of samples, no fl/ch; group B: fl 14.3%, fp 28.6%, ch 14.3%; group C always had at least one type of suspicious non-monomorphic MC (fl (57.1%) or fp (57.1%)) in each sample. The different histologic groups showed a similar mean SMI (benign: 2.97 ± 0.31, malignant: 3.02 ± 0.10, unclear: 2.90 ± 0.28). Between the three groups, no significant differences were found regarding number, volume or SMI value of MC.

CONCLUSION

3D structure based on the SMI of MC analysed with highest spatial resolution is not significantly associated with the B-classification of breast lesions. Thus, magnification views of MC may be omitted in the analysis of MC detected in mammograms.

Tracking the origin of simultaneous endometrial and ovarian cancer by next-generation sequencing - a case report

Background

Endometrioid adenocarcinoma of the uterus and ovarian endometrioid carcinoma share many morphological and molecular features. Differentiation between simultaneous primary carcinomas and ovarian metastases of an endometrial cancer may be very challenging but is essential for prognostic and therapeutic considerations.

Case Presentation

In the present case study of a 33 year-old patient we used targeted amplicon next-generation re-sequencing for clarifying the origin of synchronous endometrioid cancer of the corpus uteri and the left ovary. The patient developed a metachronous lung metastasis of an endometrioid adenocarcinoma four years after hyster- and adnexectomy, vaginal brachytherapy and treatment with the synthetic steroid tibolone. Removal of the metastasis and megestrol treatment for seven years led to a complete remission.

A total of 409 genes from the Ampliseq Comprehensive Cancer Panel (Ion Torrent, Thermo Fisher) were analysed by next generation sequencing and mutations in 10 genes, including ARID1A, CTNNB1, PIK3CA and PTEN were identified and confirmed by Sanger sequencing. Primary endometrial as well as ovarian cancer showed an identical mutational profile, suggesting the presence of an ovarian metastasis of the endometrial cancer, rather than a simultaneous endometrial and ovarian cancer. The metachronous lung metastasis showed a different mutational profile compared to the primary cancer. Immunohistochemical staining of the corresponding proteins suggested that the tumour development was driven by alterations in the protein function rather than by changes of the protein abundance in the cell.

Conclusions

Our results have demonstrated next generation sequencing as a valuable tool in the differentiation of synchronous primary tumours and metastases, which has an important impact on the clinical decision making process. Similar to breast cancer, targeted therapies based on mutational tumour profiling will become increasingly important in endometrial and ovarian cancer. In summary, our results support the usage of next generation sequencing as a supplementary diagnostic tool, assisting in personalized precision medicine.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3054-6) contains supplementary material, which is available to authorized users.

Uterine Tumors Resembling Ovarian Sex Cord Tumors - Treatment, recurrence, pregnancy and brief review

Background

Uterine Tumors Resembling Ovarian Sex Cord Tumors (UTROSCT) are rare tumors of low malignancy. In the past, these tumors were mainly treated by hysterectomy. More recently, some authors have proposed conservative surgical management for women wishing to preserve fertility. This article is the first to report on organ-preserving treatment in the case of recurrence or disease persistence.

Cases

We report on three patients with UTROSCT, two of them young, not having completed family planning. One even gave birth to a healthy child after fertility-preserving treatment of a persistent UTROSCT. To our knowledge, this is the first pregnancy reported after surgical treatment of a persistent UTROSCT so far.

Conclusion

A fertility-sparing approach should always be considered in young women with UTROSCT who wish to preserve their fertility, also in cases of recurrence or disease persistence.

•

First report on organ-preserving treatment in case of UTROSCT recurrence

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First pregnancy reported after surgical treatment of a persistent UTROSCT

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Fertility-preserving approach also in cases of recurrence or disease persistence

Lack of MRE11-RAD50-NBS1 (MRN) complex detection occurs frequently in low-grade epithelial ovarian cancer

BACKGROUND

BRCA1/2-deficient ovarian carcinomas are recognized as target for Poly (ADP-ribose) polymerase (PARP) inhibitors. BRCA1 and BRCA2 proteins are involved in homologous recombination repair of double-strand DNA breaks. The relevance of other homologous recombination repair proteins, e.g. MRE11, RAD50, NBS1 (MRN complex) in ovarian carcinomas is unclear. The objective of this study was to investigate the prevalence of lack of MRE11, RAD50, NBS1 protein detection in epithelial ovarian cancer (EOC).

METHODS

A tissue microarray (TMA) with 134 EOC was immunohistochemically evaluated for MRE11, RAD50 and NBS1. Data was analysed for associations with clinicopathological parameters, histological subtype, patient overall survival and mismatch repair (MMR) protein status. Sensitivity towards the PARP inhibitor BMN673 was tested in two ovarian cancer cell lines (TOV-21 and OVTOKO) using colony formation assays.

RESULTS

Lack of MRN complex protein detection was seen in 41% (55/134) of EOC and was more frequent in low-grade (57.6%; 19/33) than in high-grade EOC (18.8%; 36/101; n = 134; p = 0.04). There was an association with the ovarian carcinoma subtype (60.3%; 35/58 lack of detection in type I versus 26.3%; 20/76 in type II; n = 134; p < 0.001) as well as undetectable DNA mismatch repair proteins MLH1 and MSH2 (89.3%; 25/28; n = 131; p < 0.001). MRE11 knockdown led to moderately increased sensitivity towards the PARP inhibitor BMN673 in one ovarian carcinoma cell line in vitro.

CONCLUSIONS

Frequent lack of MRE11, RAD50, NBS1 protein detection in type I human ovarian carcinomas is observed in EOC and our data suggests further investigation regarding sensitivity to PARP-inhibition in tumours lacking MRE11 expression.

Palbociclib as a first-line treatment in oestrogen receptor-positive, HER2-negative, advanced breast cancer not cost-effective with current pricing: a health economic analysis of the Swiss Group for Clinical Cancer Research (SAKK)

Endocrine therapy continues to be the optimal systemic treatment for metastatic ER(+)HER2(-) breast cancer. The CDK4/6 inhibitor palbociclib combined with letrozole has recently been shown to significantly improve progression-free survival. Here we examined the cost-effectiveness of this regimen for the Swiss healthcare system. A Markov cohort simulation based on the PALOMA-1 trial (Finn et al. in Lancet Oncol 16:25-35, 2015) was used as the clinical course. Input parameters were based on summary trial data. Costs were assessed from the Swiss healthcare system perspective. Adding palbociclib to letrozole (PALLET) compared to letrozole monotherapy was estimated to cost an additional CHF342,440 and gain 1.14 quality-adjusted life years, resulting in an incremental cost-effectiveness ratio (ICER) of CHF301,227/QALY gained. In univariate sensitivity analyses, no tested variation in key parameters resulted in an ICER below a willingness-to-pay threshold of CHF100,000/QALY. PALLET had a 0 % probability of being cost-effective in probabilistic sensitivity analyses. Lowering PALLET's price by 75 % resulted in an ICER of CHF73,995/QALY and a 73 % probability of being cost-effective. At current prices, PALLET would cost the Swiss healthcare system an additional CHF155 million/year. Palbociclib plus letrozole cannot be considered cost-effective for the first-line treatment of patients with metastatic breast cancer in the Swiss healthcare system.

Acrokeratosis paraneoplastica in serous ovarian carcinoma: case report

Background

Acrokeratosis paraneoplastica is a rare paraneoplastic phenomenon associated with upper aerodigestive tract carcinomas, usually manifesting as psoriasiform keratosis over the acral sites. It is primarily seen in white males above the age of 40 years. Here we report a case of paraneoplastic acrokeratosis in a woman with serous ovarian cancer. To the best of our knowledge, no similar case has been reported previously.

Case presentation

We report the case of a 60-year-old woman diagnosed with a serous ovarian cancer and complaining of a thickening and peeling of the skin on her feet. Clinical and histological examination, as well as the course of disease, confirmed the diagnosis of a paraneoplastic plantar keratosis. Under systemic chemotherapy with carboplatin and paclitaxel the lesion resolved gradually in concordance with tumour marker CA 125.

Conclusions

We present the reported case of paraneoplastic acrokeratosis associated with advanced high-grade ovarian cancer.

Loss of ARID1A expression sensitizes cancer cells to PI3K- and AKT-inhibition

ARID1A mutations are observed in various tumors, including ovarian clear cell (OCCC) and endometrioid carcinomas, endometrial, and breast carcinomas. They commonly result in loss of ARID1A-protein expression and frequently co-occur with PI3K/AKT-pathway activating mechanisms. The aim of this study was to test the hypothesis as to whether PI3K/AKT-pathway activation is a critical mechanism in ARID1A-mutated tumors and if consequently ARID1A-deficient tumors show increased sensitivity to treatment with PI3K- and AKT-inhibitors. Upon ARID1A knockdown, MCF7 breast cancer cells and primary MRC5 cells exhibited a significantly increased sensitivity towards the AKT-inhibitors MK-2206 and perifosine, as well as the PI3K-inhibitor buparlisib. Knockdown of ARID1A in MCF7 led to an increase of pAKT-Ser⁴⁷³. AKT-inhibition with MK-2206 led to increased apoptosis and to a decrease of pS6K in ARID1A-depleted MCF7 cells but not in the controls. In five OCCC cell lines ARID1A-deficiency correlated with increased pAKT-Ser⁴⁷³ levels and with sensitivity towards treatment with the AKT-inhibitor MK-2206. In conclusion, ARID1A-deficient cancer cells demonstrate an increased sensitivity to treatment with small molecule inhibitors of the PI3K/AKT-pathway. These findings suggest a specific requirement of the PI3K/AKT pathway in ARID1A-deficient tumors and reveal a synthetic lethal interaction between loss of ARID1A expression and inhibition of the PI3K/AKT pathway.

Prolonged complete remission of metastatic HER2-positive breast cancer after continuous trastuzumab treatment: a case report and review of the literature

Metastatic breast cancer is considered an incurable disease. Targeted treatments against the human epidermal growth factor receptor 2 (HER2), however, significantly improve survival in patients with metastatic HER2-positive breast cancer. Some patients may respond with prolonged complete remission. Evidence on safety of long-term trastuzumab and risk of relapse after trastuzumab cessation is limited. We present a case of an 81-year-old patient with HER2-amplified metastatic breast cancer (MBC) in the liver. Following taxane-based chemotherapy in combination with trastuzumab after local treatment resulted in a complete radiological remission after 21 months of trastuzumab maintenance therapy. The patient remains in complete remission 6 years later and continues to receive trastuzumab as maintenance therapy. Prolonged remission in cases with complete response under trastuzumab-based regimens for metastatic HER2-positive breast cancer can be observed in some patients. Reviewing the few available cases published in the literature, these patients share some common characteristics: hormone receptor negative disease and metastases to the liver. There is no evidence that trastuzumab maintenance treatment can be safely interrupted after a certain time period.

Effect of MRE11 loss on PARP-inhibitor sensitivity in endometrial cancer in vitro

AIM OF THE STUDY

To evaluate the frequency of MRE11/RAD50/NBS1 (MRN)-complex loss of protein expression in endometrial cancers (EC) and to determine whether loss of MRE11 renders the cancer cells sensitive to Poly(ADP-ribose) polymerase (PARP)-inhibitory treatment.

METHODS

MRN expression was examined in 521 samples of endometrial carcinomas and in 10 cancer cell lines. A putative mutation hotspot in the form of an intronic poly(T) allele in MRE11 was sequenced in selected cases (n = 26). Sensitivity to the PARP-inhibitor, BMN673 was tested in colony formation assays before and after MRE11 silencing using siRNA. Homologous recombination (HR) DNA repair was evaluated by RAD51-foci formation assay upon irradiation and drug treatment.

RESULTS

Loss of MRE11 protein was found in 30.7% of EC tumours and significantly associated with loss of RAD50, NBS1 and mismatch repair protein expression. One endometrial cell line showed a markedly reduced MRE11 expression due to a homozygous poly(T) mutation of MRE11, thereby exhibiting an increased sensitivity to BMN673. MRE11 depletion sensitizes MRE11 expressing EC cell lines to the treatment with BMN673. The increased sensitivity to PARP-inhibition correlates with reduced RAD51 foci formation upon ionizing radiation in MRE11-depleted cells.

CONCLUSION

Loss of the MRE11 protein predicts sensitivity to PARP-inhibitor sensitivity in vitro, defining it as an additional synthetic lethal gene with PARP. The high incidence of MRE11 loss in ECs can be potentially exploited for PARP-inhibitor therapy. Furthermore, MRE11 protein expression using immunohistochemistry could be investigated as a predictive biomarker for PARP-inhibitor treatment.

Characterization of the genomic features and expressed fusion genes in micropapillary carcinomas of the breast

Micropapillary carcinoma (MPC) is a rare histological special type of breast cancer, characterized by an aggressive clinical behaviour and a pattern of copy number aberrations (CNAs) distinct from that of grade- and oestrogen receptor (ER)-matched invasive carcinomas of no special type (IC-NSTs). The aims of this study were to determine whether MPCs are underpinned by a recurrent fusion gene(s) or mutations in 273 genes recurrently mutated in breast cancer. Sixteen MPCs were subjected to microarray-based comparative genomic hybridization (aCGH) analysis and Sequenom OncoCarta mutation analysis. Eight and five MPCs were subjected to targeted capture and RNA sequencing, respectively. aCGH analysis confirmed our previous observations about the repertoire of CNAs of MPCs. Sequencing analysis revealed a spectrum of mutations similar to those of luminal B IC-NSTs, and recurrent mutations affecting mitogen-activated protein kinase family genes and NBPF10. RNA-sequencing analysis identified 17 high-confidence fusion genes, eight of which were validated and two of which were in-frame. No recurrent fusions were identified in an independent series of MPCs and IC-NSTs. Forced expression of in-frame fusion genes (SLC2A1-FAF1 and BCAS4-AURKA) resulted in increased viability of breast cancer cells. In addition, genomic disruption of CDK12 caused by out-of-frame rearrangements was found in one MPC and in 13% of HER2-positive breast cancers, identified through a re-analysis of publicly available massively parallel sequencing data. In vitro analyses revealed that CDK12 gene disruption results in sensitivity to PARP inhibition, and forced expression of wild-type CDK12 in a CDK12-null cell line model resulted in relative resistance to PARP inhibition. Our findings demonstrate that MPCs are neither defined by highly recurrent mutations in the 273 genes tested, nor underpinned by a recurrent fusion gene. Although seemingly private genetic events, some of the fusion transcripts found in MPCs may play a role in maintenance of a malignant phenotype and potentially offer therapeutic opportunities.

ARID1A mutations and PI3K/AKT pathway alterations in endometriosis and endometriosis-associated ovarian carcinomas

Endometriosis is a common gynecological disease affecting 6%–10% of women of reproductive age and is characterized by the presence of endometrial-like tissue in localizations outside of the uterine cavity as, e.g., endometriotic ovarian cysts. Mainly, two epithelial ovarian carcinoma subtypes, the ovarian clear cell carcinomas (OCCC) and the endometrioid ovarian carcinomas (EnOC), have been molecularly and epidemiologically linked to endometriosis. Mutations in the gene encoding the AT-rich interacting domain containing protein 1A (ARID1A) have been found to occur in high frequency in OCCC and EnOC. The majority of these mutations lead to a loss of expression of the ARID1A protein, which is a subunit of the SWI/SNF chromatin remodeling complex and considered as a bona fide tumor suppressor. ARID1A mutations frequently co-occur with mutations, leading to an activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway, such as mutations in PIK3CA encoding the catalytic subunit, p110α, of PI3K. In combination with recent functional observations, these findings strongly suggest cooperating mechanisms between the two pathways. The occurrence of ARID1A mutations and alterations in the PI3K/AKT pathway in endometriosis and endometriosis-associated ovarian carcinomas, as well as the possible functional and clinical implications are discussed in this review.

Histone deacetylase inhibitors down-regulate G-protein-coupled estrogen receptor and the GPER-antagonist G-15 inhibits proliferation in endometriotic cells

OBJECTIVE

To investigate whether histone deacetylase inhibitors reduce the expression of the G-protein-coupled estrogen receptor (GPER) and whether the functional inhibition of GPER by the antagonist G-15 decreases the proliferation of endometriotic cells.

DESIGN

In vitro study.

SETTING

University hospital.

PATIENT(S)

Immortalized epithelial endometriotic cells.

INTERVENTION(S)

Treatment with the histone deacetylase inhibitor romidepsin or suberoylanilide hydroxamic acid (SAHA), or with the GPER antagonist G-15.

MAIN OUTCOME MEASURE(S)

Western blot analysis and quantitative real-time polymerase chain reaction (PCR) were used to monitor the expression of GPER in response to drug treatment. Effects of GPER stimulation and inhibition on cell proliferation were investigated by the 93-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide (Sigma) (MTT) assay.

RESULT(S)

Our results demonstrate that romidepsin and SAHA reduce GPER expression in a concentration-dependent manner. This reduction correlated with the accumulation of acetylated histones. No decreased expression of the estrogen receptor (ER)-α and ERβ was found under comparable experimental conditions. Pretreatment of endometriotic cells with the GPER agonist G-1 stimulated cell proliferation accompanied by rapid Akt phosphorylation. G-15 reversed this stimulation and inhibited cell proliferation, which was accompanied by Akt dephosphorylation.

CONCLUSION(S)

G-protein-coupled estrogen receptor is proposed as a potential therapeutic target in endometriosis. The down-regulation of GPER and/or the impairment of its function may reduce the estrogen responsiveness in endometriosis, and therefore might be considered a possible treatment option of endometriosis.

Clinical presentation and surgical management of invasive lobular carcinoma of the breast

Invasive lobular carcinoma is the second most common histological type of breast cancer and differs from invasive ductal carcinoma also in some clinical features. Multifocal or multicentric as well as contralateral diseases are more frequently found among patients with lobular carcinoma. Tumor size at diagnosis is larger than in patients with ductal carcinoma due to diagnostic challenges associated with lobular histology. For surgical management, breast conserving surgery followed by radiotherapy offers equal local control as mastectomy. Controversy however exists regarding risk for positive margins and subsequent need for second operations. Axillary staging can be safely performed by sentinel node biopsy if lymph nodes are clinically negative, even in multifocal or multicentric disease.

Loss of ARID1A/BAF250a-expression in endometriosis: a biomarker for risk of carcinogenic transformation?

Mutations of the tumor-suppressor gene ARID1A result in the loss of protein expression of the BRG-associated factor 250a (BAF250a), a large subunit of transcription-regulating Human SWI/SNF complexes, which have an important role in the control of cell proliferation and tumor suppression. ARID1A mutations are particularly frequent in endometriosis-associated ovarian clear cell and endometrioid carcinomas, and were recently described as a possible key mechanism and early step in the transformation of endometriosis into cancer. Here, we examined the immunohistochemical expression pattern of BAF250a in a tissue microarray including 74 endometriosis and 30 endometrium samples. Ovarian cancer samples (n=136) served as a control. Epithelial BAF250a expression was assessable in 90/104 (87%) and stromal BAF250a expression in 95/104 (91%) of the endometriosis, and endometrium cases due to lack of adequate tissue in some spots. Complete lack of BAF250a expression was observed in three endometriomas (n=3/20, 15%) and one deep-infiltrating endometriosis sample (n=1/22, 5%), but in none of the peritoneal endometriosis (n=0/16) and eutopic endometrium samples (n=0/30). A comparison of the mean immunoreactivity scores revealed a significantly lower expression rate of BAF250a in endometriomas compared with normal endometrium (P<0.0005), as well as peritoneal (P=0.003) and deep-infiltrating endometriosis (P=0.02). Our data demonstrates that a complete loss of BAF250a expression is observable in some endometriotic lesions, especially in endometriomas. In addition, we report that a partial loss of BAF250a expression is occurring in the form of cell clusters indicating a clonal loss of BAF250a expression in these cells. The loss of expression of the tumor-suppressor protein BAF250a in some endometriomas possibly indicates a risk of malignant transformation in these cases, which could be of importance in the determination of individual treatment strategies. However, its role and value as a prognostic parameter in endometriosis needs to be further studied.

Expression of the G protein-coupled estrogen receptor (GPER) in endometriosis: a tissue microarray study

BACKGROUND

The G protein-coupled estrogen receptor (GPER) is thought to be involved in non-genomic estrogen responses as well as processes such as cell proliferation and migration. In this study, we analyzed GPER expression patterns from endometriosis samples and normal endometrial tissue samples and compared these expression profiles to those of the classical sex hormone receptors.

METHODS

A tissue microarray, which included 74 samples from different types of endometriosis (27 ovarian, 19 peritoneal and 28 deep-infiltrating) and 30 samples from normal endometrial tissue, was used to compare the expression levels of the GPER, estrogen receptor (ER)-alpha, ER-beta and progesterone receptor (PR). The immunoreactive score (IRS) was calculated separately for epithelium and stroma as the product of the staining intensity and the percentage of positive cells. The expression levels of the hormonal receptors were dichotomized into low (IRS < 6) and high (IRS > = 6) expression groups.

RESULTS

The mean epithelial IRS (+/- standard deviation, range) of cytoplasmic GPER expression was 1.2 (+/- 1.7, 0-4) in normal endometrium and 5.1 (+/- 3.5, 0-12) in endometriosis (p < 0.001), of nuclear GPER 6.4 (+/- 2.6, 0-12) and 6.8 (+/- 2.9, 2-12; p = 0.71), of ER-alpha 10.6 (+/- 2.4, 3-12) and 9.8 (+/- 3.0, 2-12; p = 0.26), of ER-beta 2.4 (+/- 2.2; 0-8) and 5.6 (+/- 2.6; 0-10; p < 0.001), and of PR 11.5 (+/- 1.7; 3-12) and 8.1 (+/- 4.5; 0-12; p < 0.001), respectively. The mean stromal IRS of nuclear GPER expression was 7.7 (+/- 3.0; 2-12) in endometrium and 10.8 (+/- 1.7; 6-12) in endometriosis (p < 0.001), of ER-alpha 8.7 (+/- 3.1; 2-12) and 10.6 (+/- 2.4; 2-12; p = 0.001), of ER-beta 1.8 (+/- 2.0; 0-8) and 5.4 (+/- 2.5; 0-10; p < 0.001), and of PR 11.7 (+/- 0.9; 8-12) and 10.9 (+/- 2.0; 3-12; p = 0.044), respectively. Cytoplasmic GPER expression was not detectable in the stroma of endometrium and endometriosis. The observed frequency of high epithelial cytoplasmic GPER expression levels was 50% (n = 30/60) in the endometriosis and none (0/30) in the normal endometrium samples (p < 0.001). High epithelial cytoplasmic GPER expression levels were more frequent in endometriomas (14/20, 70%; p = 0.01), as compared to peritoneal (9/18, 50%) or deep-infiltrating endometriotic lesions (7/22, 31.8%). The frequency of high stromal nuclear GPER expression levels was 100% (n = 74/74) in endometriosis and 76.7% (n = 23/30) in normal endometrium (p < 0.001). The frequency of high epithelial nuclear GPER expression levels did not differ between endometriosis and normal endometrium.

CONCLUSIONS

The present data indicate a unique GPER expression pattern in endometriosis, especially in endometriomas as compared to the normal endometrium. The overexpression of GPER in endometriotic lesions suggests a potential role for GPER in the hormonal regulation of endometriosis, which should be taken into consideration for future hormonal treatment strategies.

Expression pattern of class I histone deacetylases in vulvar intraepithelial neoplasia and vulvar cancer: a tissue microarray study

BACKGROUND

Epigenetic regulation is an important mechanism leading to cancer initiation and promotion. Histone acetylation by histone deacetylases (HDACs) represents an important part of it. The development of HDAC inhibitors has identified the utility of HDACs as a therapeutic target. Little is known about the epigenetic regulation of vulvar intraepithelial neoplasia (VIN) and vulvar squamous cell cancer (VSCC). In this study, the expression of class I HDACs (HDAC 1, 2 and 3) was compared in a series of VIN and VSCC tissues.

METHODS

A tissue micro array (TMA) with specimens from 106 patients with high-grade VIN and 59 patients with vulvar cancer was constructed. The expression of HDACs 1, 2 and 3 were analyzed with immunohistochemistry (IHC). The nuclear expression pattern was evaluated in terms of intensity and percentage of stained nuclei and was compared between vulvar preinvasive lesions and vulvar cancer.

RESULTS

HDAC 2 expression was significantly higher in VIN than in VSCC (p < 0.001, Fisher's test). Also, 88.7% (n = 94/106) of VIN samples and only 54.5% (n = 31/57) of VSCC samples were scored at the maximum level. Conversely, HDAC 3 expression was significantly higher in VSCC (93%, 53/57) compared to VIN (73.6%, 78/106, p = 0.003), whereas only a small difference in the expression of HDAC 1 was found between these two entities of vulvar neoplasia.

CONCLUSIONS

These results suggest that epigenetic regulation plays a considerable role in the transformation of VIN to invasive vulvar neoplasia.

Revisiting the role of antiandrogen strategies in ovarian cancer

Androgen receptors are frequently expressed in epithelial ovarian cancer (EOC). Their role in the development of EOC is not fully understood. In the present review we first discuss the epidemiological data linking a hyperandrogen state to a higher risk for ovarian cancer, second describe in vitro studies of the role of androgens in influencing the growth of EOC, and finally review the completed clinical trials with compounds that exploit the androgen axis in patients with ovarian cancer. The therapeutic approaches that inhibit androgen signaling have so far produced only modest response rates. In the light of new data regarding the role of androgen stimulation in the evolution of EOC and the emergence of new compounds used for the treatment of other hormone-driven malignancies, such as prostate and breast cancer, we provide suggestions for new studies of antiandrogen therapeutics in the treatment of EOC. A specific example is the new agent abiraterone. In addition, we propose a panel of molecules that could be assessed as potential biomarkers that may aid patient selection for this approach in the future.

Synthetic lethality of PARP inhibition in cancers lacking BRCA1 and BRCA2 mutations

Utilizing the concept of synthetic lethality has provided new opportunities for the development of targeted therapies, by allowing the targeting of loss of function genetic aberrations. In cancer cells with BRCA1 or BRCA2 loss of function, which harbor deficiency of DNA repair by homologous recombination, inhibition of PARP1 enzymatic activity leads to an accumulation of single strand breaks that are converted to double strand breaks but cannot be repaired by homologous recombination. Inhibition of PARP has therefore been advanced as a novel targeted therapy for cancers harboring BRCA1/2 mutations. Preclinical and preliminary clinical evidence, however, suggests a potentially broader scope for PARP inhibitors. Loss of function of various proteins involved in double strand break repair other than BRCA1/2 has been suggested to be synthetically lethal with PARP inhibition. Inactivation of these genes has been reported in a subset of human cancers and might therefore constitute predictive biomarkers for PARP inhibition. Here we discuss the evidence that the clinical use of PARP inhibition may be broader than targeting of cancers in BRCA1/2 germ-line mutation carriers.

Abstract 3917: EMSY amplification and overexpression is not associated with defective homologous recombination and does not predict sensitivity to cisplatin or PARP inhibitors

EMSY is a gene amplified in 13-18% of breast and ovarian cancers, and encodes a protein reported to be a binding partner for BRCA2, that when overexpressed causes impairment of BRCA2 functions and so might constitute a mechanism for BRCA2 inactivation in non-hereditary breast and ovarian cancers. We hypothesised that if EMSY amplification abrogates BRCA2 function, cells harbouring EMSY gene amplification could have an impaired ability to elicit competent homologous recombination (HR) DNA repair in the presence of DNA double strand breaks (DSBs) and thus an increased sensitivity to DNA cross-linking agents and PARP inhibitors. EMSY amplification may therefore constitute a biomarker for response to these therapies. 59 cell lines were subjected to microarray based comparative genomic hybridisation (aCGH) with a resolution of 50Kb. Ten cell lines harbouring EMSY amplification were identified. These cell lines were matched by anatomical site and biomarker expression with cell lines lacking EMSY gene amplification. In addition, CAPAN1 (BRCA2 mutant), MDAMB436 and SUM149 (BRCA1 mutant) cells were included as controls. The associations between EMSY copy number, mRNA and protein expression were determined by aCGH and fluorescence in situ hybridisation, quantitative real-time PCR and western blotting respectively. Cell viability was assessed following transfection with validated short interfering RNAi (siRNA) against EMSY. Formation of foci of phosphorylated H2AX (γH2AX), a surrogate marker of the presence of double strand breaks, and RAD51, a surrogate marker of competent HR DNA repair, were assessed in cell lines with and without EMSY gene amplification following 10Gy of ionising radiation and treatment with cisplatin or the PARP inhibitor olaparib. Cell viability following treatment with cisplatin or olaparib was assessed to determine sensitivity of cell lines with and without EMSY amplification. EMSY is not consistently overexpressed at the mRNA and protein levels in cancer cells harbouring EMSY gene amplification. No significant difference in viability was seen in cells with or without EMSY amplification following silencing of EMSY using siRNA. Cell lines with EMSY amplification were able to elicit RAD51 foci formation in the presence of DNA double strand breaks, and did not differ from cancer cells devoid of EMSY amplification in their sensitivity to cisplatin and olaparib. These cells also showed a lower sensitivity to these drugs than CAPAN1, MDA-MB436 and SUM149 cells. EMSY amplification is not associated with an impairment of cancer cells to elicit RAD51 foci formation in the presence of DNA double strand breaks and is not associated with increased sensitivity to cisplatin or olaparib. Its potential use as a biomarker for response to cisplatin and PARP inhibitors should therefore be viewed with caution.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3917. doi:10.1158/1538-7445.AM2011-3917

PTEN deficiency in endometrioid endometrial adenocarcinomas predicts sensitivity to PARP inhibitors

PTEN (phosphatase and tensin homolog) loss of function is the most common genetic aberration in endometrioid endometrial carcinomas. In addition to its well-described role in cell signaling, PTEN is involved in the maintenance of genomic stability. Loss of PTEN function causes defects in repair of DNA double-strand breaks by homologous recombination and, therefore, sensitizes cells to inhibition of the poly(adenosine diphosphate ribose) polymerase (PARP). Here, we determined the PTEN status of eight endometrioid endometrial carcinoma cell lines and correlated it with in vitro sensitivity to the PARP inhibitor KU0058948. PTEN-deficient cells showed a significantly greater sensitivity to KU0058948 than the two endometrioid endometrial carcinoma cell lines with wild-type PTEN. The cell lines lacking PTEN expression were unable to elicit a homologous recombination damage response as assayed by RAD51 focus function (a marker of competent homologous recombination DNA repair) upon irradiation and treatment with PARP inhibitors. PTEN silencing in PTEN wild-type Hec-1b cells resulted in reduced RAD51 foci formation after DNA damage and increased sensitivity to PARP inhibition. PTEN reexpression in PTEN-null cell lines resulted in enhanced RAD51 foci formation and in relative resistance to KU0058948. Given that up to 80% of endometrioid endometrial cancers lack PTEN expression, our results suggest that PARP inhibitors may be therapeutically useful for a subset of endometrioid endometrial cancers.

PPM1D gene amplification and overexpression in breast cancer: a qRT-PCR and chromogenic in situ hybridization study

PPM1D (protein phosphatase magnesium-dependent 1δ) maps to the 17q23.2 amplicon and is amplified in ∼8% of breast cancers. The PPM1D gene encodes a serine threonine phosphatase, which is involved in the regulation of several tumour suppressor pathways, including the p53 pathway. Along with others, we have recently shown that PPM1D is one of the drivers of the 17q23.2 amplicon and a promising therapeutic target. Here we investigate whether PPM1D is overexpressed when amplified in breast cancers and the correlations between PPM1D overexpression and amplification with clinicopathological features and survival of breast cancer patients from a cohort of 245 patients with invasive breast cancer treated with therapeutic surgery followed by adjuvant anthracycline-based chemotherapy. mRNA was extracted from representative sections of tumours containing >50% of tumour cells and subjected to TaqMan quantitative real-time PCR using primers for PPM1D and for two housekeeping genes. PPM1D overexpression was defined as the top quartile of expression levels. Chromogenic in situ hybridization with in-house-generated probes for PPM1D was performed. Amplification was defined as >50% of cancer cells with >5 signals per nucleus/large gene clusters. PPM1D overexpression and amplification were found in 25 and 6% of breast cancers, respectively. All cases harbouring PPM1D amplification displayed PPM1D overexpression. PPM1D overexpression was inversely correlated with expression of TOP2A, EGFR and cytokeratins 5/6 and 17. PPM1D amplification was significantly associated with HER2 overexpression, and HER2, TOP2A and CCND1 amplification. No association between PPM1D gene amplification and PPM1D mRNA overexpression with survival was observed. In conclusion, PPM1D is consistently overexpressed when amplified; however, PPM1D overexpression is more pervasive than gene amplification. PPM1D overexpression and amplification are associated with tumours displaying luminal or HER2 phenotypes. Co-amplification of PPM1D and HER2/TOP2A and CCND1 are not random events and may suggest the presence of a 'firestorm' genetic profile.

Down-regulation of the miRNA master regulators Drosha and Dicer is associated with specific subgroups of breast cancer

Down-regulation of Drosha and Dicer has been suggested to be of prognostic value in some cancers. The aims of our study were to investigate the down-regulation of Drosha and Dicer in breast cancers and its associations with clinicopathological features, molecular subtypes and outcome. Drosha and Dicer expression was assessed with real-time RT-PCR in 245 patients with breast cancer receiving adjuvant anthracycline-based chemotherapy and compared to expression levels of normal breast tissue. Drosha down-regulation was observed in 18% of cases and was associated with high grade, high Ki-67, lack of Bcl2 expression, HER2 over-expression and gene amplification and TOPO2A gene amplification. Dicer down-regulation was found in 46% of cases and was associated with lack of expression of ER, PR and Bcl2 and with high grade, high Ki-67, triple-negative and basal-like phenotypes. Drosha and Dicer were concurrently down-regulated in 15% of cases and significantly associated with high grade and high Ki-67 index. No significant associations between down-regulation of Drosha and/or Dicer and outcome were observed. Our results suggest that down-regulation of Drosha and/or Dicer is not robustly associated with the outcome of breast cancer patients treated with adjuvant anthracycline-based chemotherapy but preferentially observed in distinct subgroups of breast cancer.