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Background: Breast cancer is the most frequently diagnosed cancer in women and about 10% of breast cancer cases are hereditary. BRCA1 and BRCA2 are the genes most frequently associated with Hereditary Breast Cancer, although there are numerous other genes, such as PALB2, CHEK2 and ATM, that require to be considered as well. Germline Copy Number Variation (CNV) is one mutation type that is an important contributor to hereditary breast cancer. Nowadays, next-generation sequencing (NGS) technologies has contributed to multi-gene panel analysis used in clinical practice. Methods: In total, 1418 individuals were tested for breast cancer predisposition, using a solution-based capture approach. Targeted NGS was performed with a panel of 36 genes. The capture-based approach allowed for computational analysis of CNVs from NGS data. Results: We investigate the performance of the CNV module of the commercial software suite SeqPilot (JSI Medical Systems) and the non-commercial tool panelcn.MOPS. Both algorithms are specifically developed for CNV analysis of sequencing data reporting 99-100% sensitivity and up to 100% specificity for the prediction of CNVs up to the level of a single gene exon. All CNVs detected with these algorithms were then verified experimentally using the MLPA technique as an orthogonal assay. At least one pathogenic/likely pathogenic variant was identified in 289 samples (20.4%). CNVs accounted for 10.4% (30/289), referring to the deletion of one or more exons of a gene. Interestingly, 50% of deletions were single exon and approximately 36% of CNVs were detected in genes other than BRCA1/2. In specific, of the 30 CNVs detected, 60% occurred in BRCA1, 3.3% in BRCA2, 20% in CHEK2, 6.7% in FANCA, 6.7% in PMS2, and 3.3% in ATM. The majority of CNVs in BRCA1 were deletions of exons 19, 22, and 22-23 whereas deletions of exons 9-10 were the most common deletions in CHEK2. Detailed information of all CNVs detected is provided in Table 1. Conclusions: Our results suggest that CNV analysis should not be restricted to BRCA1/2 due to the significant proportion of CNVs (36%) in additional breast cancer predisposition genes. Furthermore, in silico CNV detection tools provide a cost-effective and feasible methodology for the identification of CNVs from NGS experiments. This outlines the clinical utility of comprehensive genetic testing that includes full sequencing and CNV analysis in hereditary breast cancer facilitating personalized management decisions for patients. Table 1.Pathogenic Copy Number Variations (CNVs) identified in this studyGeneHGVS nomenclatureOther nomenclature# detectedATMNM_000051:c.(-30+1_-29-1)_(331+1_332-1)deldeletion of exons 2-41BRCA1NM_007294:c.(5467+1_5468-1)-(*1_?)deldeletion of exon 237BRCA1NM_007294:c.(5406+1_5407-1)_(*1_?)deldeletion of exons 23-245BRCA1NM_007294:c.(5193+1_5194-1)-(5277+1_5278-1)deldeletion of exon 196BRCA2NM_000059:c.(6841+1_6842-1)_(7007+1_7008-1)deldeletion of exons 12-131CHEK2NM_007194:c.(908+1_909-1)_(1095+1_1096-1)deldeletion of exons 9-104CHEK2NM_007194:c.(792+1_793-1)_(846+1_847-1)deletion of exon 72FANCANM_000135:c.(1626+1_1627-1)_ (2852+1_2853-1)deldeletion of exons 18-291FANCANM_000135:c.(893+1_894-1)_(1359+1_1360-1)deldeletion of exons 11-141PMS2NM_000535: c.(903+1_904-1)_(988+1_989-1)deldeletion of exon 91PMS2NM_000535:c.(705+1_706-1)_(2006+1_2007-1)deldeletion of exons 7-111 Citation Format: Nikolaos Tsoulos, Konstantinos Agiannitopoulos, Georgia Pepe, Eirini Papadopoulou, Georgios N Tsaousis, Despina Apostolopoulou, Angeliki Meintani, Vassileios Venizelos, Christos Markopoulos, Rodoniki Iosifidou, Sofia Karageorgopoulou, Christos Christodoulou, Ioannis Natsiopoulos, Konstantinos Papazisis, Maria Vasilaki-Antonatou, Eleftherios Kabletsas, Amanta Psyrri, Stylianos Giassas, Dimitrios Ziogas, Efthalia Lalla, Anna Koumarianou, Christos Papadimitriou, Vahit Ozmen, Sualp Tansan, Kerim Kaban, Tahsin Ozatlı, Dan Tudor Eniu, Angelica Chiorean, Alexandru Blidaru, George Nasioulas. Different CNVs account for 10.4% of pathogenic variants in 1418 patients referred for hereditary breast cancer testing [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-09-10.

Background: Comprehensive tumor analysis by Next Generation Sequencing (NGS) is imperative for targeted and immunotherapy related biomarkers’ analysis in metastatic breast cancer enabling personalization of cancer treatment in these patients. In parallel with targeted therapies, immunotherapies are also evolving, revolutionizing cancer therapy. Thus, biomarkers such as. Microsatellite Instability (MSI), and Tumor Mutational Burden (TMB) are commonly employed in NGS analysis due to their correlation to Immune Checkpoint inhibitors treatment.Methods: In the present study, tumor molecular profile analysis was performed in 73 metastatic breast cancer patients using a broad NGS assay, which analyzes more than 500 unique cancer related genes and is able to detect relevant single nucleotide variations (SNVs), indels, copy number variations (CNVs) and gene fusions, in addition to TMB and MS) simultaneously. Results: An actionable alteration was detected in 79.45% of the patients. 35.62% of them had at least one alteration with an on label treatment associated and 10.96% received information related to an off-label treatment (Tiers 1A.1 and 2C.1 respectively). Additionally, 31.51% of the tumors harbored an alteration that could be used for clinical trial inclusion (Table 1). The most prevalent altered gene in these patients was the PIK3CA gene, with 27.40% mutation rate. Moreover, in 11 cases (15.07%) the mutation detected was in a gene involved in the Homologous recombination (HR) pathway, with evidence of response to PARP inhibitors. BRCA1/2 genes were as expected the most prominent HR mutated genes (5 out of 11 HR mutations), while the remaining HR mutations involved other HR genes (ATM, BLM, CHEK2, FANCM, RAD50). 24.66% of the tumors had a TMB value >10muts/MB and thus were eligible for ICI treatment. The addition of TMB to targeted biomarkers’ analysis increased the number of patients with an on-label treatment recommendation by 8.22%. Conclusions: Tumor molecular profile analysis using NGS, in real world samples, is a first-tier method for metastatic breast cancer and provides important information for decision making in the treatment of such patients. Importantly, simultaneous analysis for targeted therapy and immunotherapy biomarkers could lead to better tumor characterization and offered actionable information in 9 out of 10 patients tested. However, appropriate interpretation of results from such analysis is essential for implementation in clinical practice and accurate refinement of the treatment strategy.. Table 1.Biomarker's summary in the 73 patients included in the studyPercentage of patients with Tier1 variantsPercentage of patients with 2C.1 variantsPercentage of patients with 2C.2/2D variantsPercentage of patients with Tier 3 variantsPercentage of patients with TMB>10muts/MBMEDIAN TMBPercentage of MSI-High patients35.62% (26/73)10.96% (8/73)12.33% (9/73)0% (0/73)24.66% (18/73)5.050% (0/73) Citation Format: Eirini Papadopoulou, Nikolaos Tsoulos, Vasiliki Metaxa-Mariatou, Aikaterini Tsantikidi, Georgios Kapetsis, Chrysiida Florou-Chatzigiannidou, Sonia Maravelaki, Evgenia Bourkoula, Dimitrios Fotiou, Georgios Tsaousis, Nikolaos Touroutoglou, Dimitrios Trafalis, Ioannis Boukovinas, Ioannis Varthalitis, Zacharenia Saridaki, Charalampos Zoublios, Eleni Galani, George Papatsibas, Christos Papadimitriou, Tania Zlatintsi, Polixenia Iorga, Bülent Orhan, Sualp Tansan, Tahsin Özatlı, George Nasioulas. Comprehensive tumor analysis by NGS in metastatic breast cancer patients [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-13-01.

Background Tumor molecular profile analysis by Next Generation Sequencing technology is currently widely applied in clinical practice and has enabled the detection of predictive biomarkers of response to targeted treatment. In parallel with targeted therapies, immunotherapies are also evolving, revolutionizing cancer therapy, with Programmed Death-ligand 1 (PD-L1), Microsatellite instability (MSI), and Tumor Mutational Burden (TMB) analysis being the biomarkers employed most commonly. Methods In the present study, tumor molecular profile analysis was performed using a 161 gene NGS panel, containing the majority of clinically significant genes for cancer treatment selection. A variety of tumor types have been analyzed, including aggressive and hard to treat cancers such as pancreatic cancer. Besides, the clinical utility of immunotherapy biomarkers (TMB, MSI, PD-L1), was also studied. Results Molecular profile analysis was conducted in 610 cancer patients, while in 393 of them a at least one biomarker for immunotherapy response was requested. An actionable alteration was detected in 77.87% of the patients. 54.75% of them received information related to on-label or off-label treatment (Tiers 1A.1, 1A.2, 2B, and 2C.1) and 21.31% received a variant that could be used for clinical trial inclusion. The addition to immunotherapy biomarker to targeted biomarkers’ analysis in 191 cases increased the number of patients with an on-label treatment recommendation by 22.92%, while an option for on-label or off-label treatment was provided in 71.35% of the cases. Conclusions Tumor molecular profile analysis using NGS is a first-tier method for a variety of tumor types and provides important information for decision making in the treatment of cancer patients. Importantly, simultaneous analysis for targeted therapy and immunotherapy biomarkers could lead to better tumor characterization and offer actionable information in the majority of patients. Furthermore, our data suggest that one in two patients may be eligible for on-label ICI treatment based on biomarker analysis. However, appropriate interpretation of results from such analysis is essential for implementation in clinical practice and accurate refinement of treatment strategy.

Background Classification of splicing variants (SVs) in genes associated with hereditary cancer is often challenging. The aim of this study was to investigate the occurrence of SVs in hereditary cancer genes and the clinical utility of RNA analysis. Material and methods 1518 individuals were tested for cancer predisposition, using a Next Generation Sequencing (NGS) panel of 36 genes. Splicing variant analysis was performed using RT-PCR and Sanger Sequencing. Results In total, 34 different SVs were identified, 53% of which were classified as pathogenic or likely pathogenic. The remaining 16 variants were initially classified as Variant of Uncertain Significance (VUS). RNA analysis was performed for 3 novel variants. Conclusion The RNA analysis assisted in the reclassification of 20% of splicing variants from VUS to pathogenic. RNA analysis is essential in the case of uncharacterized splicing variants, for proper classification and personalized management of these patients.

Background/Aim: The use of multi-gene panels for germline testing in breast cancer enables the estimation of cancer risk and guides risk-reducing management options. The aim of this study was to present data that demonstrate the different levels of actionability for multi-gene panels used in genetic testing of breast cancer patients and their family members. Materials and Methods: We performed an analysis in our clinical database to identify breast cancer patients undergoing genetic testing. We reviewed positive results in respect of risk estimation and management, cascade family testing, secondary findings and information for treatment decision-making. Results: A total of 415 positive test reports were identified with 57.1%, 18.1%, 10.8% and 13.5% of individuals having pathogenic/likely pathogenic variants in high, moderate, low and with insufficient evidence for breast cancer risk genes, respectively. Six point seven percent of individuals were double heterozygotes. Conclusion: Germline findings in 92% of individuals are linked to evidence-based treatment information and risk estimates for predisposition to breast and/or other cancer types. The use of germline findings for treatment decision making expands the indication of genetic testing to include individuals that could benefit from targeted treatments.

e17550 Background: Ovarian cancer (OC) is the the leading cause of cancer death in females. Most cases present at advanced stage. Standard treatment is cytoreductive surgery before or after paclitaxel and carboplatin chemotherapy (CT) followed by maintenance treatment. Weekly CT is at least as effective as three weekly CT in OC, and may overcome resistance in some patients. Hyperthermia has been used alone or in combination with radiotherapy and chemotherapy in the treatment of advanced cancer. Radiofrequency hyperthermia (Oncothermia-OT) is theoretically more effective and comfortable form of hyperthermia due to its selective effects on tumor cells. Since most advanced patients have disease limited to the abdominal cavity, OT can be applied with a single electrode to cover the whole abdomen. Immediately following CT, OT may result in aggregation of DNA repair ezymes secreted in response to CT in cancer cells. Methods: We used weekly CT with paclitaxel or nab-paclitaxel with carboplatin followed immediately by OT. (Oncotherm-EHY 3010) to the whole abdomen for one hour for eighteen weeks in 22 consecutive patients with advanced (III or IV) ovarian/primary peritoneal cancer between 2016 and 2021. 19 patients received bevacizumab every three weeks in addition to chemotherapy.All pts had ECOG PS 0-1. Maintenance treatment was bevacizumab (19 patients) or olaparib (3 patients) for one year. Patients were followed by periodic CT/MRI/PET-CT and CA-125 levels. Results: All patients completed eighteen weeks of planned treatment. No unexpected or grade III-IV toxicity was observed. Complete response was obtained in 21 patients and partial response in one patient. Median follow up is 30 months (range 8-73 months).18 patients are alive, with 12 patients in ongoing remission and 6 patients receiving palliative treatment. 4 patients have died of cancer. Conclusions: Although this is a single center retrospective observation, the combination of weekly paclitaxel/nab-paclitaxel and carboplatin CT in combination with immediate weekly OT appears tolerable and feasible. Despite all of the limitations of this observation, activity of CT and OT appears promising. These findings should be confirmed with prospective randomized trials.

Additional file 1: Table S1. Title: Genomic Regions and fusions analyzed with the 24 and 50 gene panels. Additional file 2: Table S2. Title: Gene alterations detected by the 161 gene panel. Description: The frequency of the different mutation types (SNVs, indels, CNV, fusions) for each gene is reported. Additional file 3: Table S3. Title: Alterations identified by the 161 gene panel in the 610 patients analyzed. Description: Genomic alterations and level of evidence of the variants detected in the 610 patients analyzed. The tumor type, age of diagnosis and gender are also reported. Additional file 4: Table S4. Title: Biomarker's summary in the 610 patients included in the study. Description: Patients' categorization based on TIER classification of their most clinically significant variant and immunotherapy biomarkers’ results are reported. Additional file 5: Figure S1. Title and description: Pancreatic cancer patients' categorization based on TIER classification of their most clinically significant variant. A. Pancreatic cancer patients' categorization based on TIER classification of their most clinically significant variant. Patients were categorized in the following categories: No Biomarker: Patients with no biomarker available, 1B: Patients harboring biomarkers with strong evidence of correlation to treatment, 2C.1 KRAS: Patients with a single finding in the KRAS gene, 2C.1: Patients with biomarkers related to off-label treatment. B. Percentage of patients with On-label and off-label mutations identified and the type of alterations detected. Genes of the homologous recombination complex are labeled in blue. Additional file 6: Figure S2. Title and description: Lung cancer patients' categorization based on TIER classification. A. Lung cancer patients' categorization based on TIER classification of their most clinically significant variant. The following categories were used:, 1A.1: Patients with biomarkers related to on-label treatment, 1B: Patients harboring biomarkers with strong evidence of correlation to treatment, 2C.1: Patients with biomarkers related to off-label treatment, 1A.2R; 2C.1: Patients harboring a KRAS mutation related to resistance to treatment plus an off-label, 1A.2R: Patients harboring a KRAS mutation related to EGFR TKIs resistance, 2.C.2: Patients B. % of patients with On-label and off-label mutations identified and the type of alterations detected. Genes of the homologous recombination complex are labeled in blue. Additional file 7: Figure S3. Title and description: Breast cancer patients' categorization based on the TIER classification. A. Patients' categorization based on TIER classification of their most clinically significant variant. The following categories were used: No Biomarker: Patients with no biomarker available, 1A.1: Patients with biomarkers related to on-label treatment, 2C.1: Patients with biomarkers related to off-label treatment, 2C.2: Patients with biomarkers related to clinical trials, 2D: Patients with biomarkers with preclinical evidence. B. Percentage of patients with On-label and off-label mutations identified and the type of alterations detected. Genes of the homologous recombination complex are labeled in blue. Additional file 8: Figure S4. Title and description: Colorectal cancer patients' categorization based on TIER classification. A. Patients' categorization based on TIER classification of their most clinically significant variant. Patients were categorized in the following categories: No Mutation, 1A.1: Patients with no mutation in KRAS/NRAS genes with or without other variations, 1A.2: Patients with biomarkers included in professional guidelines, 1A.1R: Patients harboring either KRAS or NRAS mutations related to resistance to treatment. B. % of patients with on-label and off-label mutations identified and the type of alterations detected. Additional file 9: Table S5. Title and description: Alterations that would have been detected if two hotspot panels of 24 and 50 genes respectively, had been used in the 610 patients analyzed. Additional file 10: Table S6. Title and description: Simulation results of the alterations that would have been identified if the gene set of the 161 gene NGS panel was used in the PCAWG samples. Additional file 11: Table S7. Title and description: Simulation results of the alterations that would have been identified if the gene set of the 514 gene NGS panel was used in the PCAWG samples. Additional file 12: Table S8. Title and Description: TMB, PD-L1 and MSI results in the 395 patients with at least one immunotherapy biomarker requested. Additional file 13: Table S9. Title and Description: Patients with suspicious hereditary pathogenic findings detected in tumor tissue.

Non-small cell lung cancer (NSCLC) is a frequent tumor entity with high mortality. Although several newly discovered chromosomal translocations and mutations opened new horizons for targeted therapy, literature still lacks large series of NSCLC with chromosomal abberations and their correlations with histological and clinical features. We present a case of echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) translocation positive adenocarcinoma of the lung with an unusual metastatic pattern in a 29-year-old young woman. Conclusion: Young adult non-smoker female patients with an unexplained pleural effusion and signs of metastatic disease should alert the physicians straight away for all types of malignancies including lung cancer. Any skin lesions should be evaluated carefully, biopsies should be done to exclude metastasis in urgency. On the other hand, an uncommon clinical presentation of a lung cancer requires corresponding molecular testing rapidly in order to offer the best treatment option. (C) 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license.

Table S4. Individuals with 2 Pathogenic/ Likely Pathogenic variants. (PDF 557 kb)

Figure S1. Mutation types for pathogenic/likely pathogenic variants and VUS among the 1197 individuals tested with a hereditary cancer panel A. Mutation types for the 161 unique pathogenic/likely pathogenic variants identified in 264 individuals. B. Mutation types for the 424 unique VUS identified in the 417 individuals. Figure S2. Panel testing outcomes and positive results for 768 individuals with personal history of Breast cancer, grouped by gene and gene category based on breast cancer risk (See Additional file 5: Table S4). A. Outcomes of panel testing for the 768 individuals with personal history of Breast cancer. B. Percentages of genes in individuals with positive findings. C. Percentages of gene categories in individuals with positive findings. Figure S3. Retrospective analysis of the genetic testing results of the 768 individuals with personal history of Breast cancer with 4 different testing scenarios; that of analyzing the BRCA1 and BRCA2 genes only and three additional gene panels that include other high-risk, moderate-risk and low-risk genes for breast cancer (See Additional file 6: Table S5). The percentage in each case corresponds to the number of individuals identified with VUS. Figure S4. Statistical analysis of Variants of Uncertain Significance (VUS). A. Number of VUS identified per individual B. Percentage of VUS identified in each gene C. VUS stratified by gene risk category. Figure S5. Details about VUS. A. Testing outcomes for individuals tested with a hereditary cancer panel. B. Classification of VUS to sub-categories. (PDF 1131 kb)

Table S3. Large Genomic Rearrangements (LGRs). (PDF 402 kb)

Table S1. Frequency of Pathogenic and Likely Pathogenic variants among genes. (PDF 539 kb)

Background The application of the Next Generation Sequencing (NGS) technology has facilitated multigene panel testing for hereditary breast cancer (BC) in clinical practice. We performed a retrospective analysis of individuals referred for testing in our lab aiming to investigate the contribution of included genes and evaluate current genetic testing guidelines in BC. Methods In total, 1141 BC patients and 184 unaffected individuals with family history (FH) of BC were referred from physicians for testing using a multigene panel. Genomic DNA was enriched for targeted regions of 33 genes and sequencing was carried out using the Illumina NGS technology. The presence of large genomic rearrangements (LGRs) was investigated computationally and by Multiplex Ligation-dependent Probe Amplification (MLPA). Results A pathogenic variant (PV) was identified in 22% (291/1325) of analyzed individuals and in specific in 23.2% of BC patients and 14.1% of unaffected individuals (P = 0.006). Among individuals with PVs, 49.1% were located in the BRCA1/2 genes whereas 8.6%, 22.7% and 19.6% occurred in other high, moderate and low-risk genes respectively. Notably, 21 of the 291 positive individuals (7.2%) carried clinically significant variants in two different genes and 6.5% had a LGR. A retrospective analysis of positive individuals showed that 88.3% of BC patients met the NCCN criteria for further genetic risk evaluation compared to 80.8% of unaffected individuals with FH of BC (P = 0.269). In BRCA-positive cases, NCCN criteria were met in 92.3% of the referrals compared to 81.8% in individuals positive for other genes (P = 0.008). Conclusions Extended multigene panel testing in hereditary BC facilitates the detection of nearly twice as many individuals that could benefit from personalized management. In our cohort, the currently used selection criteria for HBOC failed to identify only 12.7% of individuals positive for pathogenic variants, suggesting strong selection strategies from physicians. However, our results indicate that selection criteria perform better for the identification of BRCA-positive BC patients and should be revised to facilitate towards the inclusion of BC patients with PVs in other genes. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

BACKGOUND: Hereditary cancer predisposition syndromes are believed to be responsible for approximately 5-10% of all diagnosed cancer cases. In the past, single genes analysis of certain high risk genes was used for the determination of the genetic cause of cancer heritability in certain families. The selection of genes was mainly based on the family history of the individuals analyzed and included only highly associated genes (e.g. the BRCA1 and BRCA2 genes for families with breast cancer history. Nowadays though, the application of Next Generation Sequencing (NGS) technology has facilitated multigene panel analysis and is widely used in clinical practice, for the identification of individuals with cancer predisposition gene mutations. AIM: The aim of this study was to investigate the extent and nature of mutations in 36 genes implicated in hereditary cancer predisposition in individuals referred for testing in our lab. MATERIALS & METHODS: In total, 1197 individuals were referred for testing in our lab in the past four years from Greece, Romania and Turkey. The analysis of genes involved in hereditary cancer predisposition was performed using two NGS approaches. The first 451 individuals were analyzed using an amplicon based sequencing method (26 gene panel), while the following 746 individuals were analyzed using a capture based method (33 gene panel). Genomic DNA was enriched for targeted regions of 36 genes involved in hereditary predisposition to cancer included in both versions of the panel (APC, BMPR1A, BRCA1, BRCA2, CDH1, CDK4, CDKN2A, EPCAM, MEN1, MLH1, MSH2, MSH6, MUTYH, PALB2, PMS2, PTEN, RET, SMAD4, STK11, TP53, VHL, ATM, BRIP1, CHEK2, NBN, RAD51C, RAD51D, BARD1, BLM, CHEK1, ABRAXAS1 (FAM175A), MRE11 (MRE11A), NF1, RAD50, RAD51B, XRCC2). Sequencing was carried out using the Illumina NGS technology. Reads were aligned to the reference sequence (GRCh37), and sequence changes were identified and interpreted in the context of a single clinically relevant transcript. The presence of large genomic rearrangements was investigated by computational analysis of NGS results and the use of MLPA for 13 genes. All clinically significant observations were confirmed by orthogonal technologies. RESULTS: In total, a pathogenic mutation was identified in 259 of the 1197 individuals (21.6%) analyzed while a VUS was identified in 35.7% of the cases. Clinically significant mutations were identified in 29 of the genes analyzed. Concerning the mutation distribution among individuals with positive findings, 44.7% of them were located in BRCA1/2 genes whereas 20.9%, 19.9%, and 14.5% in high, moderate and low risk genes respectively. In addition to BRCA1 and BRCA2 genes other highly mutated genes were CHEK2 (10.6%), PALB2 (7.1%), MUTYH (7.1%) and ATM (4.3%). Of note is that 25 of the 259 positive individuals (9.7%) carried clinically significant mutations in two different genes and 5.8% had a large genomic rearrangement (LGR). CONCLUSIONS: Our results support the clinical significance of analysis of a panel of genes involved in hereditary cancer predisposition. In our cohort, analysis of this panel allowed for the identification of 8.3% additional pathogenic variants in moderate/low risk genes, enabling personalized management of these individuals. Citation Format: Tsoulos N, Tsaousis GN, Papadopoulou E, Agiannitopoulos K, Pepe G, Kambouri S, Apessos A, Diamantopoulos N, Floros T, Iosifidou R, Katopodi O, Koumarianou A, Markopoulos C, Papazisis K, Venizelos V, Xanthakis I, Xepapadakis G, Banu E, Eniu DT, Negru S, Stanculeanu DL, Ungureanu A, Ozmen V, Tansan S, Tekinel M, Yalcin S, Nasioulas G. Analysis of hereditary cancer syndromes by using a panel of genes: Novel and multiple pathogenic mutations [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 P4-03-07.

BACKGROUND: Mobilized blood progenitor cells rapidly reconstitute hematopoiesis in patients after dose-intensive chemotherapy. However, optimal timing and methods of mobilized blood progenitor cell collection have yet to be fully defined. STUDY DESIGN AND METHODS: The utility of large-volume leukapheresis (LVL; > 15 L blood processed) in collecting target doses of mononuclear cells (7 × 10(8)/kg) for use in autologous hematopoietic rescue was investigated. LVL was begun at a standardized interval (14 days) after a course of limited chemotherapy and subsequent daily recombinant human granulocyte-macrophage-colony- stimulating factor administration to mobilize blood progenitor cells into the circulation. With each LVL procedure, mononuclear cells, colony-forming units-granulocyte-macrophage (CFU-GM), burst-forming units-erythroid, mixed colonies, total clonogenic progenitor cells, and CD34+ cells collected per kg of patient weight were counted. After high- dose chemotherapy and infusion of cryopreserved mobilized blood progenitor cells, the days needed for neutrophils to reach levels of > 0.5 × 10(9) per L and for platelets to reach levels of > 20 × 10(9) per L were recorded. RESULTS: In 14 previously treated cancer patients, an average of 28.9 +/− 4.9 L of blood was processed per LVL (n = 35) to collect medians of 2.5 × 10(8) mononuclear cells per kg (range, 1.0- 7.4), 14 × 10(4) CFU-GM per kg (0-208), 27 × 10(4) clonogenic progenitor cells per kg (0-370), and 2.8 × 10(6) CD34+ cells per kg (0- 112.5). Fifty-seven percent of patients (8/14) required one or two LVL procedures to collect adequate blood progenitor cells (range, 1–4). After dose-intensive chemotherapy, 13 patients received medians of 6.8 × 10(8) mononuclear cells per kg (range, 5.1-9.9), 53 × 10(4) CFU-GM per kg (9-208), and 12 × 10(6) CD34+ cells per kg (3.6-112.5). Rapid hematopoietic reconstitution occurred with 10 days (range, 8–12) and 9 days (6-15), respectively, for neutrophil and platelet recoveries. CONCLUSION: Scheduled LVL, beginning on Day 14 after the administration of granulocyte-macrophage-colony-stimulating factor following chemotherapy, is a convenient and efficient method of collecting blood progenitor cells. The mononuclear cells so obtained effected consistent and rapid hematopoietic reconstitution in a highly reproducible manner in a group of heavily treated patients.

Background Treatment options for advanced non-small-cell lung cancer are inadequate. There remains a critical need for more effective systemic therapies. Methods Forty-one patients with advanced non-small-cell lung cancer were treated on a 28-day cycle with a very high-dose, cisplatin-based three-drug regimen. A treatment cycle consisted of an intravenous (IV) injection of cisplatin 100 mg/m2 on days 1 and 8; etoposide 60 mg/m2 IV over 30 minutes on days 1, 2, 8, and 9 (cycles 1 and 3 only); and mitomycin C 8 mg/m2 IV bolus on day 1 (cycles 2 and 4 only) (PEM regimen). Results The median dose intensity of cisplatin delivered was 49 mg/m2/wk, or 98% of the planned dose. One patient achieved a complete response and 16 patients a partial response or regression, yielding an overall objective response rate of 41%. The median duration of response was 21 weeks. Median survival of all patients was 38 weeks. Neurologic toxicity was dose limiting. The frequency of peripheral neuropathy and ototoxicity was directly related to cumulative cisplatin dose. In five patients, a progressive peripheral neuropathy developed after discontinuation of cisplatin. Hematologic toxicity also was significant. Conclusions This very high-dose, cisplatin-based chemotherapy regimen has appreciable activity in advanced non-small-cell lung cancer. In comparison with previous reports on the use of very high-dose cisplatin alone, however, this combination appears at best to be only marginally more active, to confer no additional survival advantage, and to be considerably more toxic.

e22223 Background: More recently, studies have reported that the activation of coagulation and fibrinolysis may play important role in tumor progression. The process of blood coagulation results in...

e12536 Background: Approximately 5-10% of breast cancer cases are hereditary. Germline mutations in the BRCA1 and BRCA2genes are responsible for 80% of inherited breast cancer cases. Carriers of su...

Purpose: To determine the effect of a semisynthetic progesterone, megestrol acetate (MA), on the cytotoxicity of various chemotherapeutic agents including vincristine, doxorubicin, actinomycin-D, taxol, vinblastine and colchicine in cell lines with or without P-gp expression. Methods: Three cell lines with high P-gp expression (two colon cancer and one leukemia), and a control cell line with no P-gp expression were exposed to chemotherapeutic agents in the presence or absence of MA and drug sensitivity was determined using the MTT colorimetric assay. P-gp-170 expression was detected by flow cytometry using JSB-1 monoclonal antibody and the functionality of MDR expression was tested by rhodamine-123 uptake studies. In vitro drug accumulation studies were performed using [3H]-vincristine. The results were subjected to paired t-test analysis and 95% confidence intervals were determined in cytotoxicity tests. Results: MA augmented the cytotoxicity of vincristine, but not doxorubicin, actinomycin-D, taxol, vinblastine or colchicine in the three P-gp-expressing cell lines, whereas verapamil augmented the cytotoxicity of doxorubicin and vincristine. MA did not augment the cytotoxicity of vincristine in the P-gp-negative HUT-102 cell line. Conclusion: MA augmented vincristine cytotoxicity in P-gp-expressing cell lines. However, this phenomenon did not occur with the other classic MDR drugs. Therefore, the augmentation of vincristine cytotoxicity by MA can be explained either by involvement of a different mechanism that coexists with the mdr-1 phenotype or by the presence of a different affinity or binding site on the P-gp molecule for MA compared to that for the other classic MDR drugs and verapamil.

e11042 Background: The RS assay has been shown to quantify the likelihood of distant recurrence and also predict the magnitude of benefit from chemotherapy (CT) in women with estrogen receptor posi...