In the era of precision oncology, comprehensive molecular profiling is critical for guiding targeted and immunotherapy strategies. This study presents the analytical and clinical validation of a 1021-gene next-generation sequencing (NGS) panel, designed for use with both formalin-fixed paraffin-embedded (FFPE) tissue- and liquid-biopsy specimens. Analytical validation confirmed the assay’s high sensitivity and specificity across variant types—including SNVs (Single Nucleotide Variations), indels, CNVs (Copy Number Variations), and fusions—down to a 0.5% variant allele frequency. The assay also accurately identified microsatellite instability (MSI) and tumor mutational burden (TMB), essential biomarkers for immunotherapy. Clinical validation was performed on over 1300 solid tumor samples from diverse histologies, revealing actionable alterations in over 50% of cases. The panel detected on-label treatment biomarkers in 12.57% of patients, increasing to 20.15% when immunotherapy markers were included. Additionally, the assay demonstrated strong concordance with orthogonal methods and was effective in detecting variants in plasma-derived circulating tumor DNA in 70% of evaluable cases. These findings support the robust performance and broad clinical applicability of the 1021-gene panel for comprehensive genomic profiling in both tissue and liquid biopsies, offering a valuable tool for personalized cancer treatment.

Background/Aim: Germline copy number variation (CNV) is a type of genetic variant that predisposes significantly to inherited cancers. Today, next-generation sequencing (NGS) technologies have contributed to multi gene panel analysis in clinical practice. Materials and Methods: A total of 2,163 patients were screened for cancer susceptibility, using a solution-based capture method. A panel of 52 genes was used for targeted NGS. The capture-based approach enables computational analysis of CNVs from NGS data. We studied the performance of the CNV module of the commercial software suite SeqPilot (JSI Medical Systems) and of the non-commercial tool panelcn.MOPS. Additionally, we tested the performance of digital multiplex ligation-dependent probe amplification (digitalMLPA). Results: Pathogenic/likely pathogenic variants (P/LP) were identified in 464 samples (21.5%). CNV accounts for 10.8% (50/464) of pathogenic variants, referring to deletion/duplication of one or more exons of a gene. In patients with breast and ovarian cancer, CNVs accounted for 10.2% and 6.8% of pathogenic variants, respectively. In colorectal cancer patients, CNV accounted for 28.6% of pathogenic/likely pathogenic variants. Conclusion: In silico CNV detection tools provide a viable and cost-effective method to identify CNVs from NGS experiments. CNVs constitute a substantial percentage of P/LP variants, since they represent up to one of every ten P/LP findings identified by NGS multigene analysis; therefore, their evaluation is highly recommended to improve the diagnostic yield of hereditary cancer analysis.

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.

As with other solid tumors, comprehensive geriatric assessment should be performed before the treatment of GI system cancers. Chronological age alone is not a contraindication to treatment. Physiological age and performance status are more important. Healthy elderly patients without comorbidity benefit from treatment as much as young people. In patients with comorbidity, the dose may be reduced or a single agent may be preferred for cytotoxic treatments. In these cases, side effect monitoring and management gains importance. This section summarizes the characteristics of management and treatment of digestive system cancers in the elderly population.

Background : Tumor molecular profile is of great importance for the detection of biomarkers of response to targeted treatment due to the increased availability, with concomitant reduction of cost, of Next Generation Sequencing technology (NGS). In parallel to 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, a 161 gene NGS panel, containing the majority of clinically significant genes for cancer treatment selection, was used for tumor molecular profile analysis. 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. At least one actionable alteration was detected in 77.70% of the patients. 54.59% 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 22.40%, while an option for on-label or off-label treatment was provided in 71.35% of the cases. Conclusions : Tumor molecular profile analysis by NGS is a first-tier methodology for a variety of tumor types, which provides critical information for treatment decision making in cancer patients. Importantly, simultaneous analysis for targeted therapy and immunotherapy biomarkers could lead to a better tumor characterization and provide actionable information in the majority of patients. Moreover, our results indicate that one in two patients is eligible for ICI treatment based on the biomarkers’ analysis. However, when these analyses are performed, the challenge is their implementation in clinical practice. Multidisciplinary patient management is critical to the refinement of the strategy incorporating such information.

The tumor objective response rate (ORR) is an important parameter to demonstrate the efficacy of a treatment in oncology.The ORR is valuable for clinical decision making in routine practice and a significant end-point for reporting the results of clinical trials.World Health Organization and Response Evaluation Criteria in Solid Tumors (RECIST) are anatomic response criteria developed mainly for cytotoxic chemotherapy.These criteria are based on the visual assessment of tumor size in morphological images provided by computed tomography (CT) or magnetic resonance imaging.Anatomic response criteria may not be optimal for biologic agents, some disease sites, and some regional therapies.Consequently, modifications of RECIST, Choi criteria and Morphologic response criteria were developed based on the concept of the evaluation of viable tumors.Despite its limitations, RECIST v1.1 is validated in prospective studies, is widely accepted by regulatory agencies and has recently shown good performance for targeted cancer agents.Finally, some alternatives of RECIST were developed as immune-specific response criteria for checkpoint inhibitors.Immune RECIST criteria are based essentially on defining true progressive disease after a confirmatory imaging.Some graphical methods may be useful to show longitudinal change in the tumor burden over time.Tumor tissue is a tridimensional heterogenous mass, and tumor shrinkage is not always symmetrical; thus, metabolic response assessments using positron emission tomography (PET) or PET/CT may reflect the viability of cancer cells or functional changes evolving after anticancer treatments.The metabolic response can show the benefit of a treatment earlier than anatomic shrinkage, possibly preventing delays in drug approval.Computer-assisted automated volumetric assessments, quantitative multimodality imaging in radiology, new tracers in nuclear medicine and finally artificial intelligence have great potential in future evaluations.

Colorectal cancer (CRC) is one of the most common cancers in the world.Obesity is an established risk factor for colorectal carcinogenesis.Many epidemiological and experimental studies support this link and tumor-promoting effects of obesity.Body mass index (BMI) is a marker of general obesity.Obesity is also a global health problem and is defined by World Health Organization as BMI > 30 kg/m 2 .In this chapter, we give a general review about the mechanisms of obesity on colorectal carcinogenesis and the effects of obesity on clinical outcomes such as disease-free survival (DFS), progression-free survival (PFS) and overall survival (OS), in adjuvant setting and metastatic disease, respectively.

e15507 Background: Esophagus cancer is an important cause of cancer-related deaths in Turkey as well as in the world. In our study, clinicopathological features and survival results of patients treated for esophageal cancer were presented. Methods: This study retrospectively reviewed esophageal squamous cell carcinoma (SCC) and adenocarcinoma (ADC) patients who were admitted to our center, between 2012 and 2016. Results: A total of 82 patients (56 males) with a median age of 56 years were evaluated. Seventy-one (87%) patients were diagnosed with SCC, 10 (12%) with ADC, 1 with adenosquamous carcinoma. All ADC patients were HER2 negative. The localization of tumors; lower third (55%), middle third (27%) and upper third (18%) of the esophagus. Prior to surgery, neoadjuvant chemoradiotherapy (CRT) was administered in 21 patients (26%); 10 of them receiving carboplatin and paclitaxel (CP), and 11 receiving cisplatin and 5-FU (CF). TNM classification of operated patients were as follows; Stage 1 (n = 5), stage 2 (n = 10), stage 3 (n = 8) and stage 4 (n = 1). Adjuvant chemotherapy (CF) was administered in the other 6 (7%) patients. Definitive CRT was given in 36 patients (44%), with CF being administered in 32 patients, and CP therapy in 4 patients. There were 19 patients (23%) with metastatic diagnosis and 13 of whom were treated with CF, and 4 with docetaxel-cisplatin-5FU combination. With median follow up of 21 months, median overall survival (OS) and time to progression (TTP) were 24 and 17 months, respectively. The median OS and TTP of patients with metastatic disease were 14 and th 9 months, respectively. The median OS and TTP of the patients who underwent surgery were 45 and 34 months, respectively. Conclusions: Our findings in this study regarding the rate of histology, the percentages of patients with metastatic vs. locally advanced disease, and survival rates were similar to the literature.

BACKGROUNDPrognostic factors and the standard treatment approach for gynaecological carcinosarcomas have not yet been clearly defined. Although carcinosarcomas are more aggressive than pure epithelial tumours, they are treated similarly. Serous/clear cell and endometrioid components may be predictive factors for the efficacy of adjuvant chemotherapy (CT) or radiotherapy (RT) or RT in patients with uterine and ovarian carcinosarcomas. Heterologous carcinosarcomas may benefit more from adjuvant CT.AIMSWe aimed to define the prognostic and predictive factors associated with treatment options in ovarian (OCS) and uterine carcinosarcoma (UCS).STUDY DESIGNRetrospective cross-sectional study.METHODSWe retrospectively reviewed the medical records of patients with ovarian and uterine carcinosarcoma from 2000 to 2013, and 127 women were included in this study (24 ovarian and 103 uterine). Patients admitted to seventeen oncology centres in Turkey between 2000 and December 2013 with a histologically proven diagnosis of uterine carcinosarcoma with FIGO 2009 stage I-III and patients with sufficient data obtained from well-kept medical records were included in this study. Stage IV tumours were excluded. The patient records were retrospectively reviewed. Data from 104 patients were evaluated for this study.RESULTSAge (≥70 years) was a poor prognostic factor for UCS (p=0.036). Pelvic±para aortic lymph node dissection did not affect overall survival (OS) (p=0.35). Macroscopic residual disease was related with OS (p<0.01). The median OS was significantly longer in stage I-II patients than stage III patients (p=0.03). Adjuvant treatment improved OS (p=0.013). Adjuvant radiotherapy tended to increase the median OS (p=0.075). However, this tendency was observed in UCS (p=0.08) rather than OCS (p=0.6).Adjuvant chemotherapy had no effect on OS (p=0.15).Adjuvant radiotherapy significantly prolonged the median OS in patients with endometrioid component (p=0.034). A serous/clear cell component was a negative prognostic factor (p=0.035). Patients with serous/clear cell histology for whom adjuvant chemotherapy was applied had significantly longer OS (p=0.019), and there was no beneficial effect of adjuvant radiotherapy (p=0.4). Adjuvant chemotherapy was effective in heterologous tumours (p=0.026). In multivariate analysis, the stage and chemotherapy were prognostic factors for all patients. Age was an independent prognostic factor for UCS. However, serous/clear cell histology and radiotherapy tended to be significant prognostic factors.CONCLUSIONThe primary location, the histological type of sarcomatous and the epithelial component may be predictive factors for the efficacy of chemotherapy or radiotherapy in UCS and OCS.

BackgroundSoft tissue sarcomas (STSs) are rare malignant tumors of embryogenic mesoderm origin. Primary thoracic STSs account for a small percentage of all STSs and limited published information is available. This study aimed to identify the prognostic factors for thoracic STSs and evaluate the disease's clinical outcomes.MethodsThe medical records of 109 patients with thoracic STSs who were treated between 2003 and 2013 were retrospectively reviewed. Patients' survival rates were analyzed and potential prognostic factors evaluated.ResultsThe median follow-up period was 29 months (range: 1-121 months). STSs were most frequently localized on the chest wall (n = 42; 38.5%) and lungs (n = 42; 38.5%). The most common histological types were malignant fibrous histiocytoma (n = 23; 21.1%), liposarcoma (n = 17; 15.6%), and leiomyosarcoma (n = 16; 14.7%). The median survival time of all patients was 40.3 months (95% confidence interval, 14.22-66.37 months), with one and five-year survival rates of 93.4% and 63.5%, respectively. Univariate analysis of all groups revealed that metastatic stage, unresectability, tumor diameter of >10cm, tumor location other than the chest wall, and grade 3 diseases were predictable of poor survival. However, only grade 3 diseases and tumor location other than the chest wall were confirmed by multivariate analysis as poor prognostic factors.ConclusionsPrimary thoracic STSs are rarely seen malignant tumors. Our results indicated that patients with low-grade tumors and those localized on the chest wall often experienced better survival outcomes.

PURPOSE:Adding targeted therapies to chemotherapy in metastatic colorectal cancer (CRC) improves response rates and survival. KRAS is a predictive indicator for anti-epidermal growth factor receptor (EGFR) treatments. The most important reasons for KRAS discordance are intratumoral heterogeneity and incorrect mutation analysis. Evaluating the status of KRAS in primary and metastatic lesions becomes even more crucial to ensure efficient usage of anti-EGFR treatments.METHODS:Patients with metastatic CRC, whose primary disease and liver and/or lung metastases were operated, were retrospectively evaluated, and KRAS assessment was performed on 31 patients who were suitable for DNA analysis. Pyrosequencing with polymerase chain reaction (PCR) was used for KRAS analysis.RESULTS:The median age of 31 patients diagnosed with rectal cancer (N=13) and colon cancer (N=18) was 63 years (range 33-73). Metastasectomy locations included the liver (N=27), lung (N=3), and both lung and liver (N=1). KRAS discordance was detected in 22% (7/31) of the patients. While 3 patients with detected discordance had mutated KRAS in the primary material, wild type KRAS was detected in their liver or lung lesions. On the other hand, while 4 patients had wild type KRAS in the primary material, mutated KRAS was determined in their liver or lung lesions. The McNemar test revealed no significant discordance between primary and metastatic disease (p=1.00). No progression free survival (PFS) difference was detected between patients with determined discordance and patients with undetermined discordance (10.6 vs 14.7 months, p=0.719).CONCLUSION:This is the first study to evaluate KRAS discordance between primary and metastasis in CRC patients, who underwent metastasectomy, together with survival data. In the literature and recent studies with large patient numbers in which modern KRAS tests were used, the KRAS discordance rate varies between 3-12%. In our study, a higher KRAS discordance (22%) was detected, and no survival difference was determined between patients with or without discordance. In recent years, the rising interest in borderline resectable disease may bring forward discussions related to which material the KRAS status should be analyzed.

ÖZETDev hücreli kemik tümörü (DHKT) nadir görülen bir primer kemik tümörüdür.Günümüzde anti osteoklastik aktiviteye sahip bifosfanat tedavisi kullanılmaktadır.Denosumab tamamen insan kaynaklı monoklonal antikordur ve metastatik DHKT'de hastalık progresyonunu inhibe eder.Akciğer metastazı olan 3 DHKT'li hastayı özetledik.Hastalar 12 ile 18 ay arasında denosumab kullanmışlardı.Tedavi

ABSTRACT Aim: Gastric cancer is often diagnosed in advanced stage. Palliative chemotherapy or best supportive care is recommended for patients with metastatic gastric patients. In several clinical trials palliative chemotherapy improved overall survival (OS) and disease free survival (DFS), but the survival benefit of second line chemotherapy was demostrated in small cohort studies. The main aim of our study is to compare the efficacy of second line fluorouracil-folinic acid-irinotecan (FOLFIRI) and epirubicin-oxaliplatin-capacitabine (EOX) regimens. Methods: Metastatic gastric cancer patients who progressed after completed modified docetaxel-cisplatin-fluorouracil (DCF) regimens were included. A total 105 patients were included to this study; 55 and 50 patients were treated with EOX and FOLFIRI regimens. The clinicopathological and demographic characteristics of all patients were collected from the medical charts. Kaplan–Meier survival analysis was carried out for DFS and OS. Results: The median follow-up of our study was 15 (4-85) months. In both groups, all of the patient were treated with prior modified DCF. In our study, prior median DCF cycle was 4 (2-6) and 5 (3-8) in EOX and FOLFIRI groups, respectively. Median cycle of chemotherapy was 3 (1-8) and 3.5 (1-6) in EOX and FOLFIRI groups, respectively (P = 0.44). Median DFS was 5.3 months and 6.3 months (P = 0.91) whereas median OS was 6 and 7 months (P = 0.67) in EOX and FOLFIRI groups, respectively. Six months and 1-year DFS rate was 43.4% and 13.7% in EOX regimen; 54.7% and 11.3% in FOLFIRI regimen arms (P = 0.91). Six months and 1-year OS rate was 48.1% and 24.1% in EOX regimen; 53.8% and 29.3% in FOLFIRI regimen arms (P = 0.67). Conclusions: Published trials and meta-analyses showed the efficacy of second-line chemotherapy in the treatment of metastatic gastric cancer, but the optimal treatment regimen was not still known. In our trial both platin based and irinotecan based second line chemotherapies showed similar efficacy in metastatic gastric cancer. Like iriotekan based regimens, oxaliplatin based regimens can be effective in the second line treatment of metastatic gastric cancer patients. Disclosure: All authors have declared no conflicts of interest.