Assistance by adaptative damping on a complex bimanual task in laparoscopic surgery

PURPOSE

Laparoscopic surgery has improved outcomes in abdominal surgery, but presents kinematic restrictions for surgeons. Robotic comanipulation with adaptative damping has been investigated in simple laparoscopic tasks. The present protocol aimed to determine the contribution of adaptive damping in complex bimanual tasks approaching clinical setting.

METHODS

Fourteen residents in general surgery performed three exercises, and for each three repetitions without (classic repetitions) and three with robotic assistance (robotic repetitions) in a randomised order. The exercises chosen were trajectory, modified Pea on a Peg and intracorporeal suture. Task performance, gesture performance, workload and impression were measured. Also, a semi-directed interview was performed to collect the participants' feeling about companipulated robots and their potential application in clinical practice.

RESULTS

Adaptative damping assistance did not impact task performance, but allowed an economy of movement in the non-dominant hand during suture exercise (distance 916 ± 500 mm in classic vs. 563 ± 261 mm in robotic, p < 0.001). Perceived workload (p = 0.12) and user's impression were not different between classic and robotic repetitions, except novelty (p < 0.001). Participants' interviews revealed their interest for the robotic devices, particularly the gravity compensation, and were ready to use the adaptative damping provided an intermittent use, for example to dissect dangerous areas.

CONCLUSION

Adaptative damping applied by comanipulated robots does not influence the performance of the task, but improves the performance of the gesture itself, particularly for the non-dominant hand, and during the realisation of a complex task like suturing. For residents in digestive surgery, this assistance does increase workload, and they would use this help in the operating room under certain conditions.

Deleterious and ethnic-related BRCA1/2 mutations in tissue and blood of Egyptian colorectal cancer patients and its correlation with human papillomavirus

This study aimed to identify BRCA1/2 mutational patterns in the tissue and blood of Egyptian colorectal cancer (CRC) patients and to study the possible correlation of this mutational pattern with Human papillomavirus (HPV) infection. Eighty-two colonoscopic biopsies and forty-six blood samples were collected from Egyptian CRC patients, as well as blood samples of age and sex-matched healthy controls (n = 43) were enrolled. The libraries were performed using Qiaseq Human BRCA1 and BRCA2 targeted DNA panel and sequenced via Ion proton sequencer. Also, the CRC tissues were subjected to conventional PCR targeting the HPV Late 1 (L1) region. Our analysis revealed that the BRCA-DNA damage pathway had been altered in more than 65% of the CRC patients. Comparing tissue and blood samples from CRC patients, 25 somatic mutations were found exclusively in tissue, while 41 germline mutations were found exclusively in blood. Additionally, we identified 23 shared BRCA1/2 pathogenic (PVs) mutations in both blood and tissue samples, with a significantly higher frequency in blood samples compared to tissue samples. The most affected exon in BRCA1 was exon 10, while the most affected exons in BRCA2 were 11, 14, 18, 24, and 27 exons. Notably, we revealed an ethnic-related cluster of polymorphism variants in our population closely related to South Asian and African ethnicities. Novel PVs were identified and submitted to the ClinVar database. HPV was found in 23.8% of the CRC tissues, and 54% of HPV-positive cases had somatic BRCA1/2 PVs. The results of this research point to a possible connection between infection with HPV and BRCA1/2 mutations in the occurrence of colorectal cancer in the Egyptian population, which has a mixed ethnic background. Our data also indicate that liquid biopsy (blood samples) may be more representative than tissue samples for detecting BRCA1/2 mutations. These findings may have implications for cancer screening and the development of personalized, targeted therapies, such as PARP inhibitors, which can effectively target BRCA1/2 mutations.

Frequency of Pathogenic Germline Mutations in Early and Late Onset Familial Breast Cancer Patients Using Multi-Gene Panel Sequencing: An Egyptian Study

BACKGROUND

Precision oncology has been increasingly used in clinical practice and rapidly evolving in the oncology field. Thus, this study was performed to assess the frequency of germline mutations in early and late onset familial breast cancer (BC) Egyptian patients using multi-gene panel sequencing to better understand the contribution of the inherited germline mutations in BC predisposition. Moreover, to determine the actionable deleterious mutations associated with familial BC that might be used as biomarker for early cancer detection.

METHODS

Whole blood samples were collected from 101 Egyptian patients selected for BC family history, in addition to 50 age-matched healthy controls. A QIAseq targeted DNA panel (human BC panel) was used to assess the frequency of germline mutations.

RESULTS

A total of 58 patients (57.4%) out of 101 were found to have 27 deleterious germline mutations in 11 cancer susceptibility genes. Of them, 32 (31.6%) patients carried more than one pathogenic mutation and each one carried at least one pathogenic mutation. The major genes harboring the pathogenic mutations were: ATM, BRCA2, BRCA1, VHL, MSH6, APC, CHEK2, MSH2, MEN1, PALB2, and MUTYH. Thirty-one patients (30.6%) had BRCA2 mutations and twenty (19.8%) had BRCA1 mutations. Our results showed that exon 10 and exon 11 harbored 3 and 5 mutations, respectively, in BRCA1 and BRCA2 genes. Our analysis also revealed that the VHL gene significantly co-occurred with each of the BRCA2 gene (p = 0.003, event ratio 11/21), the MSH2 gene (p = 0.01, 4/10), the CHEK2 gene (p = 0.02, 4/11), and the MSH6 gene (p = 0.04, 4/12). In addition, the APC gene significantly co-occurred with the MSH2 gene (p = 0.01, 3/7). Furthermore, there was a significant mutually exclusive event between the APC gene and the ATM gene (p = 0.04, 1/36). Interestingly, we identified population specific germline mutations in genes showing potentials for targeted therapy to meet the need for incorporating precision oncology into clinical practice. For example, the mutations identified in the ATM, APC, and MSH2 genes.

CONCLUSIONS

Multi-gene panel sequencing was used to detect the deleterious mutations associated with familial BC, which in turns mitigate the essential need for implementing next generation sequencing technologies in precision oncology to identify cancer predisposing genes. Moreover, identifying DNA repair gene mutations, with focus on non-BRCA genes, might serve as candidates for targeted therapy and will be increasingly used in precision oncology.

Somatic Mutations Alter Interleukin Signaling Pathways in Grade II Invasive Breast Cancer Patients: An Egyptian Experience

This study aimed to investigate the impact of somatic mutations on various interleukin signaling pathways associated with grade II invasive breast cancer (BC) in Egyptian patients to broaden our understanding of their role in promoting carcinogenesis. Fifty-five grade II invasive BC patients were included in this study. Data for somatic mutations in 45 BC patients were already available from a previous study. Data for somatic mutations of 10 new BC patients were included in the current study. Somatic mutations were identified using targeted next-generation sequencing (NGS) to study their involvement in interleukin signaling pathways. For pathway analysis, we used ingenuity variant analysis (IVA) to identify the most significantly altered pathways. We identified somatic mutations in components of the interleukin-2, interleukin-6, and inter-leukin-7 signaling pathways, including mutations in JAK1, JAK2, JAK3, SOCS1, IL7R, MCL1, BCL2, MTOR, and IL6ST genes. Interestingly, six mutations which were likely to be novel deleterious were identified: two in the SCH1 gene, two in the IL2 gene, and one in each of the IL7R and JUN genes. According to IVA analysis, interleukin 2, interleukin 6, and interleukin 7 signaling pathways were the most altered in 34.5%, 29%, and 23.6% of our BC group, respectively. Our multigene panel sequencing analysis reveals that our BC patients have altered interleukin signaling pathways. So, these results highlight the prominent role of interleukins in the carcinogenesis process and suggest its potential role as promising candidates for personalized therapy in Egyptian patients.

929 The Incidence and Outcomes of Delayed Laparoscopic Cholecystectomy and Bile Duct Exploration on a Unit Adopting Index Admission Surgery for All Comers. a Review of 5750 Patients

Aim

The timing of laparoscopic cholecystectomy (LC) for emergency biliary admissions remains inconsistent with national and international guidelines. The perception that LC is difficult in acute cholecystitis and the popularity of the two-session approach to pancreatitis and suspected choledocholithiasis result in delayed management.

Method

Analysis of prospectively maintained data in a unit adopting “intention to treat” during the index admission. The aim was to study the incidence of previous biliary admissions and compare the operative difficulty, complications, and postoperative outcomes with index admission LC.

Results

Of 5750 LC performed 20.8% had previous biliary admissions; one in 93% and two or more in 7%. Most presented with biliary colic (39.6%) and acute cholecystitis (27.6%). A previous biliary history was associated with increased operative difficulty (p&lt;0.001), longer operating times (86.9 v 68.1 minutes, p&lt;0.001), more post-operative complications (7.5% v 5.2%, p=0.002) and longer hospital stay (8.1 v 5.5 days, p&lt;0.001). However, conversion and mortality rates showed no significant differences.

Conclusion

Index admission LC is superior to interval cholecystectomy and should be offered to all patients fit for general anaesthesia regardless of presenting complaints. Subspecialisation should be encouraged as a major factor in optimising resource utilisation and post-operative outcomes of biliary emergencies.

Multigene Panel Sequencing Reveals Cancer-Specific and Common Somatic Mutations in Colorectal Cancer Patients: An Egyptian Experience

This study aims at identifying common pathogenic somatic mutations at different stages of colorectal carcinogenesis in Egyptian patients. Our cohort included colonoscopic biopsies collected from 120 patients: 20 biopsies from patients with inflammatory bowel disease, 38 from colonic polyp patients, and 62 from patients with colorectal cancer. On top of this, the cohort included 20 biopsies from patients with non-specific mild to moderated colitis. Targeted DNA sequencing using a customized gene panel of 96 colorectal related genes running on the Ion Torrent NGS technology was used to process the samples. Our results revealed that 69% of all cases harbored at least one somatic mutation. Fifty-seven genes were found to carry 232 somatic non-synonymous variants. The most frequently pathogenic somatic mutations were localized in TP53, APC, KRAS, and PIK3CA. In total, 16 somatic mutations were detected in the CRC group and in either the IBD or CP group. In addition, our data showed that 51% of total somatic variants were CRC-specific variants. The average number of CRC-specific variants per sample is 2.4. The top genes carrying CRC-specific mutations are APC, TP53, PIK3CA, FBXW7, ATM, and SMAD4. It seems obvious that TP53 and APC genes were the most affected genes with somatic mutations in all groups. Of interest, 85% and 28% of the APC and TP53 deleterious somatic mutations were located in Exon 14 and Exon 3, respectively. Besides, 37% and 28% of the total somatic mutations identified in APC and TP53 were CRC-specific variants, respectively. Moreover, we identified that, in 29 somatic mutations in 21 genes, their association with CRC patients was unprecedented. Ten detected variants were likely to be novel: six in PIK3CA and four variants in FBXW7. The detected P53, Wnt/βcatenin, Angiogenesis, EGFR, TGF-β and Interleukin signaling pathways were the most altered pathways in 22%, 16%, 12%, 10%, 9% and 9% of the CRC patients, respectively. These results would contribute to a better understanding of the colorectal cancer and in introducing personalized therapies for Egyptian CRC patients.

1282 Evaluation of the Basket in Catheter Technique for Transcystic Bile Duct Exploration and Suspected Ductal Stones

Aim

The ‘Basket-in-catheter’ (BIC) technique facilitates laparoscopic transcystic ductal exploration (LTCE) and increases its success rate, being easier and safer than inserting the basket alone. This study evaluates the benefits in confirmed and suspected ductal stones.

Method

Prospective preoperative, operative and postoperative data on consecutive single session ductal explorations was collected over 28 years and analysed. BIC became our default technique for the transcystic approach to confirmed or suspected bile duct stones.

Results

741 of 1225 (60.5%) attempted LTCE were performed using retrieval baskets without dilating the cystic duct (CD). BIC was used in 646 (87.2%). Of 386 (52.1%) patients undergoing successful stone retrieval 62.7% had clinical and radiological risk factors for ductal stones and 92.0% had positive intraoperative cholangiography. 355 (47.9%) patients had preoperative or operative risk factors for CBD stones and equivocal cholangiography in 25%. Basket trawling was negative and repeat cholangiography confirmed resolution of abnormalities. Choledochoscopy was utilised in 484/1225 (39.5%), either primarily or when blind trawling failed to extract stones. Retained stones occurred in 7 patients, six requiring ERCP. Bile leakage occurred in 6 patients. There were two open conversions, no biliary injuries and no mortality. Post-operative pancreatitis occurred in 7 and recurrent stones in 8 patients.

Conclusions

The BIC technique achieves successful LTCE without CD dilatation in 40%, reducing the need for choledochoscopy and choledochotomy. It facilitates safe and speedy CBD trawling when stones are suspected due to preoperative or operative risk factors or equivocal cholangiography and helps surgeons acquire and consolidate ductal exploration skills.

Abstract 2175: Identification of Somatic BRCA1/2 mutation profile in tissue-based and liquid biopsy-based next generation sequencing in Egyptian patients with breast cancer

Aim: Identification of BRCA1/2 mutations in Breast Cancer (BC) patients may help in providing genetic information to customize the therapeutic management of patients. Assessing liquid biopsies for BRCA1/2 somatic mutations could overcome the limitation of information gained from tissue biopsy. Consequently, this study aimed to identify the frequencies of pathogenic BRCA1 & BRCA2 somatic mutations in both liquid and tissue biopsies in Egyptian BC patients.

Material and methods: The study was conducted on 45 BC patients. Liquid and tissue biopsies were collected from each patient and they were profiled for BRCA1/2 mutations using next generation sequencing (NGS). Qiaseq UMI-based targeted panel was used for performing libraries. Ion proton platform was used for sequencing. The detected genetic variants at depth of coverage 500x were annotated against Cosmic, dbSNP, and Exac all databases. Polyphen-2, Sift prediction tools and Clinvar database were used to detect the biological function of the detected variants using IVA software.

Results: Variants analysis revealed that Among 45 patients, 37 (82.2%) patients were carrying one or more damaging BRCA1/2 somatic mutations. A total number of BRCA1/2 somatic variants detected was 24 and they were classified to 13 pathogenic, 7 likely pathogenic and 4 benign variants. Tissue and plasma samples of BC patients were found to harbor one detectable pathogenic somatic mutation in BRCA1 gene; c.1961delA with frequencies of 75.5% vs 17.7%, respectively. While, both samples had 8 detectable pathogenic BRCA2 somatic variants, the top 3 most frequent mutations among them were: c.5351delA (82.2% vs 40%), c.2957delA (75.56% vs 42.2%) and c.9253delA (68.89% vs 24.4%). One deleterious variant was detected merely in tissue sample; c.8940delA (55.5%). Whereas, 3 damaging variants were detected merely in plasma samples: c.8053delA (22.2%), c.6762delT (20%), c.4631delA (6.6%).Likely pathogenic BRCA2 somatic variants were also identified in both samples; c.7177delA (71.1% vs 53.3%) and c.10248delA (37.7% vs 11.1%). Moreover, 5 likely pathogenic variants were merely found in plasma samples. The most frequently detected variant among them was c.1114A&gt;C (42.2%). Our data showed that exon 10 in BRCA1 and exon 11 in BRCA2 are the most affected exons as they harbored the most frequent detected pathogenic variants.

Conclusion: Our preliminary results showed the most frequent pathogenic and likely pathogenic BRCA1/2 somatic mutations in liquid and tissue biopsies in Egyptian BC patients. This data may help in developing personalized targeted therapies that efficiently target the BRCA1/2 mutations.

Citation Format: Mai M. Lotfy, Amira Salah El-Din Youssef, Auhood Nassar, Mahmoud Kamel, Zeinab K. Hassan, Amany Abd-Elhameed Abou-Bakr, Ahmed Farahat, Mohamed M. Gomaa, Abdel Rahman N. Zekri. Identification of Somatic BRCA1/2 mutation profile in tissue-based and liquid biopsy-based next generation sequencing in Egyptian patients with breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2175.

Abstract 257: Tumor mutation burden of Egyptian breast cancer patients based on next generation sequencing

Tumor mutation burden of Egyptian breast cancer patients based on next generation sequencing Aim: This study aimed to identify the tumor mutation burden (TMB) value in Egyptian Breast cancer (BC) patients. Additionally, we aimed to find the best model to predict TMB value by the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER-2), and proliferative index Ki-67, to help expecting the prognosis of patients and predicting the possible response to immunotherapy. Patients and methods: In 58 Egyptian patients with BC, the Ion AmpliSeq Comprehensive Cancer Panel based on NGS was used to determine the TMB value of primary tumor tissues of Egyptian BC patients. The predicted TMB value was divided into 4 groups: A (0.00-0.625), B (0.626-1.25), C (1.251-2.50), and D (&gt;2.50), according to the quartile method, with group A as reference level. Different machine learning models were used to select the optimal classification model. Results: The measured TMB value was between 0 and 8.12/Mb. The TMB distribution among the studied 58 cases was: 19 cases in group A, 12 cases in group B, 14 cases in group C, and 13 cases in group D. ER positive expression was significantly associated with TMB ≤ 1.25 (ER positive vs ER-negative, OR =0.35, 95% CI: 0.04-2.98, p= 0.001). TMB ≤1.25 was significantly distributed in patients with PR positive expression (PR positive versus PR negative, OR = 0.17, 95% CI= 0.02-0.44, p= 0.002). Ki67 expression positive was significantly associated with TMB &gt;1.25 than those who were Ki-67 expression negative (Ki67 positive versus Ki67 negative, OR = 9.33, 95% CI= 2.07-42.18, p= 0.004). Also, TMB &gt;1.25 was significantly distributed in triple negative (TN) patients than non-TN patients (OR=9.69, 95% CI: 1.05-89.9, p=0.045). However, no significant differences were observed between HER2 positive and HER2 negative group (OR = 2.47, 95% CI: 0.64-9.54, p =0.19). The adjusted Pseudo-R2 was 0.329 (P&lt;0.001). The optimized logistic regression model was TMB = -27.5 -1.82 ER - 0.73 PR + 0.826 HER2 + 2.08 Ki67. Conclusion: the preliminary findings of our studied sample set revealed that level of TMB in Egyptian BC patients is relatively low. Also, TMB value in hormone receptor positive and Ki-67 expression positive Egyptian BC patients is higher than hormone receptor negative and Ki-67 expression negative patients. Moreover, TMB value can be predicted based on the expression level of ER, PR, HER-2, and Ki-67. The optimized logistic regression model was TMB = -27.5 -1.82 ER - 0.73 PR + 0.826 HER2 + 2.08 Ki67.

Citation Format: Auhood Nassar, Ahmed M. Lymona, Mai M. Lotfy, Amira Salah El-Din Youssef, Abdel-Rahman N. Zekri. Tumor mutation burden of Egyptian breast cancer patients based on next generation sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 257.

Tumor Mutation Burden Prediction Model in Egyptian Breast Cancer patients based on Next Generation Sequencing

Objectives:

This study aimed to identify the tumor mutation burden (TMB) value in Egyptian breast cancer (BC) patients. Moreover, to find the best TMB prediction model based on the expression of estrogen (ER), progesterone (PR), human epidermal growth factor receptor 2 (HER-2), and proliferation index Ki-67.

Methods:

The Ion AmpliSeq Comprehensive Cancer Panel was used to determine TMB value of 58 Egyptian BC tumor tissues. Different machine learning models were used to select the optimal classification model for prediction of TMB level according to patient’s receptor status.

Results:

The measured TMB value was between 0 and 8.12/Mb. Positive expression of ER and PR was significantly associated with TMB ≤ 1.25 [(OR =0.35, 95% CI: 0.04–2.98), (OR = 0.17, 95% CI= 0.02-0.44)] respectively. Ki-67 expression positive was significantly associated with TMB >1.25 than those who were Ki-67 expression negative (OR = 9.33, 95% CI= 2.07-42.18). However, no significant differences were observed between HER2 positive and HER2 negative groups. The optimized logistic regression model was TMB = -27.5 -1.82 ER – 0.73 PR + 0.826 HER2 + 2.08 Ki-67.

Conclusion:

Our findings revealed that TMB value can be predicted based on the expression level of ER, PR, HER-2, and Ki-67.

Abstract PO-131: Therapeutic molecular targets in Egyptian colorectal cancer patients: Time for ethnic personalized medicine

Background: Colorectal cancer (CRC) in Egypt is one of the most prevalent and deadly tumor. The pathogenesis of CRC is complex and affected by multiple factors: genetic, epigenetic and familial history of polyposis and long standing inflammatory condition. Aim: This study aimed to sequence custom panel consists of 96 tumor suppressor genes and oncogenes frequently associated with colorectal cancer (CRC) to identify the potential molecular therapeutic targets and their frequencies in the Egyptian CRC patients which may help in developing personalized therapy. Material and methods: Biopsy samples were collected from 62 CRC Egyptian patients. The libraries were performed using Qiaseq UMI-based targeted panel and sequenced via Ion proton sequencer. The detected genetic variants with an average coverage of 500x were annotated against Cosmic and dbSNP and Clinvar databases. Further Variant and Pathway analysis were performed using both Ingenuity Variant analysis (IVA) and Ingenuity Pathway analysis (IPA). Results: The Pathway Analysis revealed that Wnt-B-catenin, P53 signaling, RTK-RAS, TGF-beta signaling pathways were the most altered pathways in the CRC patients (73%. 72%, 38% & 36%, respectively).

Regarding P53 signaling pathway, it has been shown that TP53 variant (c.215C&gt;G (44%)) was the most frequent single nucleotide polymorphism (SNP) and drug response variant involved in drug efflux resistance mechanism, this variant was found to be more related to the Europe, Jewish and Latino populations (0.73, 0.72 & 0.71, respectively). In RTK-RAS signaling pathway, we identified many variants that are associated with resistant mechanism to anti EGFR therapy as well as drug efflux resistance mechanism; RET (c.2071G&gt;A (37%)) & KIT (c.1621A&gt;C (13%)) SNPs were the most frequently detected variants among the studied groups while KRAS (c.35G&gt;T(8%) & c.38G&gt;A(3%)), ERBB2(c.922G&gt;A(2%) & c.2690G&gt;A(2%)), NRAS (c.35G&gt;T(2%)) and BRAF(c.1781A&gt;G(2%) & c.1799T&gt;A(3%)) were less frequent variants. Moreover, we identified many variants as molecular targets for PD-1 and PDL-1 immunotherapy; 8 variants in APC (c.3754delT (65%), c.1742delA (13%), c.1495C&gt;T (2%), c.2055G&gt;A (2%), c.2309C&gt;G (2%), c.4588G&gt;T (2%), c.8446C&gt;T (2%) &c.3856G&gt;T (2%)), three in SMAD4 (c.1064A&gt;G (2%), c.1081C&gt;T (3%) & c.1088G&gt;A (2%)), two in PIK3CA (c.1173A&gt;G (16%) & c.3140A&gt;G (2%)) and one in PIK3R1 (c.978G&gt;A (23%)). The two variants PIK3CA (c.1173A&gt;G) & PIK3R1 (c.978G&gt;A)) were found to be more related to the African ethnicity (0.21 & 0.38, respectively).

Conclusion: In this data set, we shed the light on the most frequently identified molecular therapeutic targets and the most altered pathways that are crucial for understanding cancer predisposition and developing ethnic-based personalized therapies in the Egyptian CRC patients.

Citation Format: Amira Salah El-Din Youssef, Auhood Nassar, Mai M. Lotfy, Mohamed A. Abdel-Fattaf, Abdel-Rahman N. Zekri. Therapeutic molecular targets in Egyptian colorectal cancer patients: Time for ethnic personalized medicine [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-131.

Abstract PO-124: Mutational profiling of DNA repair and mismatch repair genes in the Egyptian colorectal cancer patients using targeted DNA sequencing

Background: Colorectal cancer (CRC) remains one of the most prevalent and deadly tumor worldwide. DNA repair and mismatch repair (MMR) genes play an important role in the occurrence and development of colorectal cancer; however, there is insufficient knowledge of DNA repair and MMR mutational profile in the Egyptian Colorectal cancer (CRC) patients which limit our understanding of its progression.

Aim: This study aimed to sequence DNA repair and mismatch repair (MMR) genes frequently associated with colorectal cancer (CRC) progression in order to identify their frequencies in the Egyptian CRC patients which may help in understanding colorectal carcinogenesis and developing personalized therapy. Material and methods: Biopsy samples were collected from 62 CRC Egyptian patients. The libraries were performed using Qiaseq UMI-based targeted panel and sequenced via Ion proton sequencer. The detected genetic variants with an average coverage of 500x were annotated against Cosmic and dbSNP and Clinvar databases using Ingenuity Variant analysis (IVA). Results: Regarding DNA repair genes, our results revealed that ATM & CHEK2 genes harbored 19 and 4 variants, respectively. The most frequently detected pathogenic mutations in the ATM were COSM1350741 (29%), COSM1351020 (26%) & COSM41596 (17%) while those pathogenic mutations detected in the CHEK2 were rs772683219 (2%) & rs587780181 (2%). As per MMR genes, it has been shown that MLH1, MLH3, MSH2, MSH3, MSH6, PMS1 & PMS2 harbored 6, 6, 8, 6, 7, 3 & 4 variants, respectively. The identified pathogenic mutations in the MLH1 were COSM1131469 (32%) & rs63750217 (2%), while those pathogenic mutations detected in the MSH2 were rs63749832 (7%), COSM26124 (5%), rs63750084 (2%). Moreover, the highly frequent detected pathogenic mutations were COSM1438892 (7%) in MSH3, & rs267608093 (10%), COSM13395 (6%), COSM13394 (3%) in MSH6. Regarding PMS1, The most frequently detected pathogenic mutation was COSM1404081 (10%). However, no pathogenic mutations were detected in both PMS2 & MLH3 genes. Conclusion: In this data set, we shed the light on the most frequently identified DNA repair and MMR genetic mutations that are crucial for understanding colorectal carcinogenesis and developing ethnic-based personalized therapies in the Egyptian CRC patients.

Citation Format: Amira Salah El-Din Youssef, Mai M. Lotfy, Auhood Nassar, Abdel-Rahman N. Zekri. Mutational profiling of DNA repair and mismatch repair genes in the Egyptian colorectal cancer patients using targeted DNA sequencing [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-124.

Photodynamic therapy versus candida antigen immunotherapy in plane wart treatment: a comparative controlled study

INTRODUCTION

Plane warts, mostly found on the face, present a challenge to treat as most destructive methods can lead to unpleasant cosmetic outcome. Alternative therapeutic methods should be evaluated. The aim of this study is to evaluate the clinical efficacy and adverse effects of photodynamic therapy with methylene blue and intense pulsed light in comparison to candida antigen immunotherapy in the treatment of plane warts.

METHODS

The study included 39 patients with plane warts assigned into 3 groups. Group I received photodynamic therapy using methylene blue followed by IPL illumination, group II received immunotherapy using 0.1 ml of candida albicans antigen and group III received 0.1 ml saline as a control.

RESULTS

Complete response was detected in (46.1%) of patients in group I compared to (61.5%) in group II and no response in group III.

CONCLUSION

Candida antigen immunotherapy is superior to photodynamic therapy in plane warts treatment with absence of recurrence and comparable side effects in both groups.

Abstract 3616: Somatic mutation profiling of colorectal cancer by targeted next generation sequencing

Aim: This study aimed to sequence custom 96 genes of tumor suppressor genes and oncogenes frequently associated with colorectal cancer (CRC) to identify the frequency of the detected genetic mutations in the disease progression of CRC patients and to develop personalized therapy in those somatic mutation carriers.

Material and methods: Biopsy samples were collected from Egyptian patients classified into inflammatory bowel disease (IBD) (n=20), colonic polyp (CP) (n=38) and CRC (n=60) patients as well as subjects with chronic non-specific colitis served as a control group (n=20). The libraries were performed using Qiaseq UMI-based targeted panel and sequenced via Ion proton sequencer. The detected genetic variants with an average coverage of 500x were annotated against Cosmic and dbSNP and Clinvar databases.

Results: Analysis revealed that 52 genes harbor 128, 47 genes harbor 111, 40 genes harbor 71 and 39 genes harbor 66 somatic variants were detected in the CRC, CP, IBD and control groups; respectively. ARID1A (c.5548dupG (5%)), ATM (c.2572T&gt;C (10%)), AXIN2 (c.1975C&gt;T (5%)), FLCN (c.1285dupC (8%)), KRAS (c.35G&gt;T (8%)), MSH6 (c.3261dupC (5%)), SLC9A9 (c.1765A&gt;G (10%)), TP53 (c.1024C&gt;T (5%)) were found to be the highly frequently detected pathogenic CRC specific variants. We also identified 29 genes harbor 43 common variants. The highly frequently common detected variants were ACVR2A (c.1310delA), ATM (c.5557G&gt;A), BRCA1 (c.3548A&gt;G, c.2612C&gt;T), BRCA2 (c.1114A&gt;C), IGF2 (c.677delG), KIT (c.1621A&gt;C), MLH1 (c.655A&gt;G), MLK4 (c.2223G&gt;T, c.2182G&gt;A), PIK3CA (c.1173A&gt;G), PTPN12 (c.964G&gt;A), RET (c.2071G&gt;A), TP53 (c.121delG, c.215C&gt;G)

Conclusion: Our data showed that our Egyptian genetic makeup is different from other population. Also, the identified somatic mutations are crucial for understanding cancer predisposition and developing personalized therapies for the Egyptian colorectal cancer patients.

Citation Format: Amira Salah El-Din Youssef, Ahmed Moustafa, Ahmed Osama Touny, Zeinab K. Hassan, Mohammed Mohey Eldin, Mai M. Lotfy, Auhood Nassar, ola sayed, Abdel-Rahman N. Zekri. Somatic mutation profiling of colorectal cancer by targeted next generation sequencing [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3616.

Abstract 2491: Targeted next generation sequencing identifies somatic variants in Egyptian breast cancer patients

Breast cancer (BC) is the leading cause of cancer-related death in women worldwide and its incidence is progressively increasing in Egypt. Recent advances in next generation sequencing have been used to detect the acquired somatic mutations driving BC. However, there is insufficient knowledge of the acquired somatic mutations in Egyptian BC patients which limit our understanding of disease progression. Up to our knowledge, this is the first Egyptian cohort to sequence a multiple-gene panel of cancer related genes on BC patients.

409 cancer related genes were sequenced in 46 fresh breast tumors of Egyptian BC patients to identify somatic mutations and their frequencies, using the Ion Ampliseq Comprehensive Cancer Panel based on the Ion torrent DNA sequencing technology. The identified sequences were mapped to the human reference genome (hg19) and the detected genetic variants were annotated against different reference databases. The average depth of coverage is 668X and the average of the aligned reads which cover the target regions is 99.6%.

Our results showed that TP53 and PIK3CA were the most top two frequently mutated genes. We detected 15 different somatic mutations in TP53 and 8 different ones in PIK3CA, each in 27 samples (58.7%). Most of the detected somatic mutations in TP53 and PIK3CA are pathogenic and well established in known hotspot regions. According to Clinvar database; we found 19 pathogenic somatic mutations: 7 in p53, 5 in PIK3CA, and single variants of VHL, STK11, AKT1, KRAS, IDH2, PTEN and ERBB2. We also identified 5 variants with uncertain significance (4 in TP53 and 1 in CEBPA) and 4 variants with conflicting interpretations of pathogenicity (2 in TP53 and 1 in each of APC and JAK3). Moreover, 4 novel variants were identified in JAK2, MTOR, KIT and EPHB.

In this cohort, we shed the light on the most frequently detected somatic mutations in Egyptian BC patients which allows for more knowledge about BC progression.

Citation Format: Auhood Nassar, Mohamed abouelhoda, Abeer Bahnassy, Amira Salah El-Din Youssef, Mai M. Lotfy, ola S. Ahmed, Hoda Ismail, Abdel-Rahman N. Zekri. Targeted next generation sequencing identifies somatic variants in Egyptian breast cancer patients [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2491.

Abstract 3615: Profiling of BRCA1 & BRCA2 mutations in Egyptian colorectal cancer patients via next generation sequencing

Aim: This study aimed to sequence BRCA1 & BRCA2 genes to identify the frequency of the detected genetic mutations in the disease progression of colorectal cancer (CRC) and to estimate colorectal cancer risks in those BRCA mutation carriers.

Material and methods: 140 biopsy samples were collected from Egyptian patients categorized into inflammatory bowel disease (IBD) (n=20), colonic polyp (CP) (n=38) and CRC (n=62) patients as well as subjects with chronic colitis served as a control group (n=20). The libraries were performed using Qiaseq UMI-based targeted panel and sequenced via Ion proton sequencer. The detected genetic variants at 500x were annotated against Cosmic, dbSNP, exac all, Polyphen2, Sift and Clinvar databases.

Results: Analysis revealed that BRCA1 gene harbored 26, 19, 8 and 11 variants in the CRC, CP, IBD and control groups; respectively. Exon 10 was the most affected exon harbored 7 pathogenic variants in the CRC group. Two out of 7 were the most frequently detected common pathogenic variants associated with disease progression from colitis to CRC (c.1961delA (11%) & c.3214delC (16%). Moreover, 3 common begnin SNP variants were found to be related to ethnicity (c.3548A&gt;G (58%), c.2612C&gt;T (60%), c.4900A&gt;G (69%).

Moreover, BRCA2 gene harbored 48, 29, 24 and 18 variants in the CRC, CP, IBD and control groups respectively. Exon 2, 11, 23 were the most affected exons harbored 12 pathogenic variants in the CRC group. Four out of 12 were the most frequently detected common pathogenic variants associated with disease progression from colitis to CRC (c.3860delA (8%), c.5351delA (18%), c.9097delA (24%) & c.36delT (34%).

Conclusion: Our data showed that BRCA1 & BRCA2 genes analyzed by Next-Generation Sequencing (NGS) identifies large number of pathogenic and begnin variants that are crucial for understanding CRC predisposition and early detection. Also, developing personalized therapies that efficiently target the individual CRC-specific mutations.

Key words: Egyptian Colorectal cancer, BRCA1, BRCA2, pathogenic, begnin, Next Generation Sequencing

Citation Format: Amira Salah El-Din Youssef, Ahmed Osama Touny, Zeinab K. Hassan, Mohammed Mohey Eldin, Mai M. Lotfy, Auhood Nassar, Mohamed El-Hadidi, Ali Kishk, ola sayed, Abdel-Rahman N. Zekri. Profiling of BRCA1 & BRCA2 mutations in Egyptian colorectal cancer patients via next generation sequencing [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3615.

Targeted next generation sequencing identifies somatic mutations in a cohort of Egyptian breast cancer patients

Breast cancer (BC) incidence is progressively increasing in Egypt. However, there is insufficient knowledge of the acquired somatic mutations in Egyptian BC patients which limit our understanding of its progression. To the best of our knowledge, this is the first Egyptian cohort to sequence a multiple-gene panel of cancer related genes on BC patients. Four hundred and nine cancer related genes were sequenced in 46 fresh breast tumors of Egyptian BC patients to identify somatic mutations and their frequencies. TP53 and PIK3CA were the most top two frequently mutated genes. We detected 15 different somatic mutations in TP53 and 8 different ones in PIK3CA, each in 27 samples (58.7%). According to Clinvar database; we found 19 pathogenic somatic mutations: 7 in Tp53, 5 in PIK3CA, and single variants of VHL, STK11, AKT1, KRAS, IDH2, PTEN and ERBB2. We also identified 5 variants with uncertain significance (4 in TP53 and 1 in CEBPA) and 4 variants with conflicting interpretations of pathogenicity (2 in TP53 and 1 in each of APC and JAK3). Moreover, one drug response variant (p.P72R) in TP53 was detected in 8 samples. Furthermore, four novel variants were identified in JAK2, MTOR, KIT and EPHB. Further analysis, by Ingenuity Variant Analysis software (IVA), showed that PI3K/AKT signaling is altered in greater than 50% of Egyptian BC patients which implicates PI3K/AKT signaling as a therapeutic target. In this cohort, we shed the light on the most frequently detected somatic mutations and the most altered pathway in Egyptian BC patients.

AB0730 ASSOCIATION OF SPONDYLOARTHRITIS AND FAMILIAL MEDITERRANEAN FEVER AND IMPACT ON DISEASE PHENOTYPE: A SYSTEMATIC REVIEW OF THE LITERATURE

Background:

Spondyloarthritis (SpA) and Familial Meditaerranean fever (FMF) may co-exist in certain populations, and have some overlapping manifestations (oligo-arthritis, hip involvement). Their association may impact disease phenotype and may affect disease management.

Objectives:

To evaluate the association of SpA and FMF and its impact on disease phenotype and management.

Methods:

A systematic literature search was conducted with the keywords spondyloarthritis and familial mediterranean fever from Janurary 1990 to January 2020 in PubMed and using manual cross-reference methods.

Results:

The search retrieved 74 articles, out of which 37 articles were relevant to the study question; most of the articles were case reports, with some large cohort studies of FMF and SpA (Flowchart in Figure 1).

In large FMF cohorts, the prevalence of SpA was higher compared to the general population (7.5-13%, OR around 10). M694V was a risk factor for SpA. These FMF-SpA patients were older at diagnosis, had lower fever attacks, and higher disease duration, inflammatory back pain, chronic arthritis, enthesopathy, persistent inflammation and higher resistance to Colchicine. In case series, they were responsive to anti-TNF therapy.

In large SpA cohorts, MEFV mutation, particularly M694V, was found in 15-35% (even without associated FMF). In most cohorts, MEFV mutation carriers didn’t have any distinct disease phenotype, except for some reports of higher ESR, more hip involvement, higher BASFI and higher BASDAI. Genome-wide association studies and case reports suggest an implication for IL-1 and thus a role for Anakinra therapy in these patients.

Conclusion:

In FMF or SpA patients with resistance to conventional therapy, the evaluation of disease association should be performed as it may have significant impact on disease management.

References:

[1]Li et al, Plos Genetics 2019. Watad et al, Frontiers Immunol 2019. Atas et al, Rheumatol Int 2019. Cherqaoui et al, JBS 2017. Zhong et al. Plos One 2017. Ornek et al, Arch Rheumatol 2016. Cinar et al, Rheumatol Int 2008. Durmur et al, JBS 2007.

Figure 1.

Flowchart of the systematic literature search (Spondyloarthritis, Familial Mediterranean Fever; January 1990-2020).

Disclosure of Interests:

Nelly Ziade Speakers bureau: Abbvie, Janssen, Lilly, Novartis, Pfizer, Roche, Sanofi, Aref Nassar: None declared

Complete remission with immunotherapy: Case report of a patient with metastatic bladder cancer to the humerus

Bladder cancer is the sixth most common malignancy in the United States. Cisplatin combination regimens are first line therapy for patients with metastatic urothelial bladder cancer who are eligible candidates and no treatments have shown to improve outcome compared to chemotherapy for the past 20 years. Significant advances were made in past 2-3 years and the most significant was the introduction of checkpoints inhibitors in bladder cancer treatment. We present a patient diagnosed with metastatic urothelial carcinoma who progressed while on cisplatin/gemcitabine chemotherapy in the form of oligometastasis to the bone. He has achieved a durable complete response with atezolizumab.

Abstract 1777: Correlation between different C-KIT exon mutation and clinical outcome to Imatinib Mesylate treatment in patients with gastro-intestinal stromal tumors (GIST)

Aim: C-KIT exon mutations were assessed in patients with gastrointestinal stromal tumor (GIST) in relation to patients’ characteristics, response to treatment and survival rates.

Methods: C-KIT mutations were assessed in the representative formalin fixed paraffinembedded tissues (FFPETs) of 89 patients with GIST compared to 35 normal control (NC) subjects using the Real Time PCR (Rt-PCR) and immunohistochemistry (IHC).

Results: C-KIT mutations were detected in 61/89 (68.5%) patients, compared to none of the NC subjects (P=&lt;0.001). Most mutations were detected in exon 11 (50.8%), followed by exon 9 (24.5%), exon 13 (19.6%), exon 7 (4.1%), and exon 12 (only 1%). C-KIT protein expression was detected in 69 (77.5%) patients compared to none of the NC subjects (p=&lt;0.001). Significant measure of agreement was detected between C-KIT expression by IHC and and RT-PCR (K=0.774, p=0.0001).

The presence of C-KIT mutations associated significantly with large tumor size (P=0.01), High mitotic rate, lymph nodes metastasis and high tumor risk (p=0.001, for all). Patients with exon 11 mutations 26/31 (83.9%) had a better response to treatment compared to those with exon nine 7 (46.7%) and exon 13 mutation 1/12 (8.3%; P=0.001). Exon 11 mutations associated significantly with better PFS and OS compared to those with exon 9 and 13 mutations (P= 0.001, P= 0.0001; respectively). On univariate analysis, Exon 13 mutations was the most significantly associated with reduced PFS (P=0.0001), whereas advanced disease stage, absence of adequate safety margins and the site of exon mutation associated significantly with reduced OS. (P=0.012, P=0.05 and P=0.005; respectively.

Conclusion: GIST patients with C-KIT exon 11 mutations have a better response to imatinib treatment (predictive value), better OS and lower risk of disease progression than those with exon 9 and 13 mutations. Our specified mutations in exons 9& 13 mutations could be used as an independent prognostic factor for GIST patients.

Citation Format: Abeer A. Bahnnasy, Ola Khorshid, Mona S. Abdellateif, Ghada Y. Zakaria, Nasr M. Allahloubi, Auhood Nassar, Abdel-Rahman N. Zekri. Correlation between different C-KIT exon mutation and clinical outcome to Imatinib Mesylate treatment in patients with gastro-intestinal stromal tumors (GIST) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1777.

Abstract 4243: Genetic variants frequently detected in Egyptian breast cancer tumors: Comprehensive cancer panel by ion torrent DNA sequencing technology

Breast cancer is the leading cause of cancer-related death in women worldwide. In Egypt, it is the most common cancer among females and its incidence is progressively increasing with a great tendency to occur with advanced stages in younger ages. Due to the heterogeneity of breast cancer, it was classified into different subtypes, each exhibits a unique gene mutation profile, based on biological characteristics and on gene expression pattern. Therefore, further research is needed to investigate the unknown genetic mutations involved in the progression of that disease. This study aimed to sequence 409 exons of tumor suppressor genes and oncogenes to identify the frequency of the detected genetic mutations in breast cancer using Ion Comprehensive Cancer Panel. Forty-eight tissue samples of various breast cancer subtypes were collected from National Cancer Institute (NCI) outpatient clinic, Cairo University. Analysis revealed 191 exonic and splicing variants. In this paper, we will address the most frequently detected Egyptian genetic variants (in 31.25 % of cases or more) as well as other deleterious variants commonly associated with breast cancer. Most of the detected genetic variants were checked in 1000g, dbSNP and Exac All databases. Other variants were found at known hotspot sites. We reported fifty-one somatic and germline mutations in thirty-two genes; AKAP9, BUB1B, RPS6KA2, AURKB, FANCA, RNF213, FGFR4, KAT6B, NLRP1, KAT6A, PER1, ERBB4, IL6ST, PIK3CA, P53, AURKA, WRN, PALB2, PTEN, GATA3, AKT1, ERBB2 and KRAS. Only KAT6B incurred non-frameshift deletion and only GATA3 had frameshift insertion while KAT6A, ERBB4 and PTEN had frameshift deletion. All the identified variants were detected with different frequencies in each breast cancer subtype. Each sample harbored at least four mutations and the maximum number of mutations per sample was twelve. The current data showed that gene panels analyzed

by Next-Generation Sequencing (NGS) identifies large number of germline and somatic mutations that is crucial for understanding cancer predisposition and developing personalized or combination therapies that efficiently target the individual breast cancer-specific mutations.

Key words: Breast cancer, Somatic mutations, Germline mutations, Ion torrent sequencing, Targeted sequencing.

Note: This abstract was not presented at the meeting.

Citation Format: Abdel-Rahman N. Zekri, Osman Mansour, Samah A. Loutfy, Mohamed M. Hafez, M. Gomaa, Abeer Bahnassy, Mai M. Lotfy, Amira S. Youssef, Ola S. Ahmed, Mohammed Abouelhouda, Auhood Nassar. Genetic variants frequently detected in Egyptian breast cancer tumors: Comprehensive cancer panel by ion torrent DNA sequencing technology [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4243.

MicroRNA Signatures for circulating CD133-positive cells in hepatocellular carcinoma with HCV infection

AIM

Molecular characterization of the CD133+ stem cells associated with hepatocarinogensis through identifying the expression patterns of specific microRNAs (miRNAs).

METHODS

We investigated the expression pattern of 13 miRNAs in purified CD133+ cells separated from the peripheral blood of healthy volunteers, chronic hepatitis C (CHC), liver cirrhosis (LC) and hepatocellular carcinoma (HCC) patients a long with bone marrow samples from the healthy volunteers and the LC patients using custom miScript miRNA PCR array.

RESULTS

The differential expression of the 13 studied miRNAs in CD133+ cells separated from the HCC patients' peripheral blood compared to the controls revealed that miR-602, miR-181b, miR-101, miR-122, miR-192, miR-125a-5p, and miR-221 were significantly up regulated (fold change = 1.8, 1.7, 2, 5.4, 1.6, 2.9 & 1.5 P value = 0.039, 0.0019, 0.0013, 0.0370, 00024, 0.000044 &0.000007 respectively). As for the HCC group compared to the CHC group; miR-602, miR-122, miR-181b, miR-125a-5p, and miR-192 were significantly up regulated (fold change = 13, 3.1, 2.8, 1.6 & 1.56, P value = 0.01, 0.001, 0.000004, 0.002 & 0.007 respectively). Upon comparing the HCC group to the LC group; miR-199a-3p, miR-192, miR-122, miR-181b, miR-224, miR-125a-5p, and miR-885-5p were significantly up regulated (fold change = 5, 6.7, 2.3, 3, 2.5, 4.2 & 39.5 P value = 0.001025, 0.000024, 0.000472, 0.000278, 0.000004, 0.000075 & 0.0000001 respectively) whereas miR-22 was significantly down regulated (fold change = 0.57 P value = 0.00002). Only, miR-192, miR-122, miR-181b and miR-125a-5p were significant common miRNAs in CD133+ cells of the HCC group compared to the other non-malignant groups.

CONCLUSION

We identified a miRNA panel comprised of four miRNAs (miR-192, miR-122, miR-181b and miR-125a-5p) that may serve as a molecular tool for characterization of the CD133+ cells associated with different stages of hepatocarinogensis. This panel may aid in developing a new target therapy specific for those CD133+ cells.

Abstract PD5-06: Prognostic value of molecular tumor infiltrating lymphocyte (mTIL) signatures in HER2-positive breast cancer patients in N9831 and FinHer/FinXX trials

Background: While previous study showed that the enrichment of immune-related gene expression was associated with outcome in HER2+ patients receiving sequential or concurrent trastuzumab (H), stromal tumor infiltrating lymphocytes (sTIL) have not been consistently shown to associate with outcome in this group of patients. Given that TIL scoring may be subjective, we analyzed molecular signatures of different subsets of tumor infiltrating immune cell populations, using NanoStringTM gene expression data to assess molecular TIL (mTIL) signature enrichment and intrinsic subtype as a function of relapse-free survival (RFS).

Methods: NanoStringTM technology was used to quantify mRNA in samples from 1,280 patients in N9831, 168 patients in FinHer, and 170 patients in FinXX. In N9831, patients in arm A were treated with chemotherapy alone (AC-T), arm B received chemotherapy followed by sequential H (AC-T-H), and arm C received H concurrently with chemotherapy (AC-TH). In the FinHer trial, H was given concurrently for 9 weeks and either 1 year or 9 weeks in FinXX trial. Cox proportional hazard ratio (HR) was used to determine the association of each gene signature with RFS. Different immune subset signatures, including CD45, B-cells, CD8 T-cells, cytotoxic-cells, and T-cells were analyzed using algorithms developed by NanoString.

Results: In N9831, CD45, cytotoxic-cell, and T-cell signatures were significantly associated with improved RFS in patients receiving chemotherapy alone and AC-T-H. However, none of the mTIL signatures were significantly associated with outcome in patients receiving AC-TH. Patients lacking CD45 enrichment had better outcome when H was given concurrently with chemotherapy. The 10-year Kaplan-Meier estimates for RFS in arm B patients with CD45 enrichment or no enrichment were 81.3% and 72.6%, respectively (HR 0.63 [95% CI, 0.42-0.93]; p = 0.02), and in arm C were 83.6% and 79.8%, respectively (HR 0.79, 95%CI 0.49-1.28; p = 0.34). Among patients with HER2-enriched subtype, all of the mTIL signatures were associated with improved RFS in arm A (AC-T) and B (AC-T-H) but remained non-significant in arm C (AC-TH). In patients with luminal subtypes, mTIL signatures were not significantly associated with outcome in patients treated with chemotherapy alone. Similar findings were observed in the FinHer and FinXX trials, in which, none of mTIL signatures were significantly associated with outcome among patients who received H.

Conclusion: This analysis sheds light on previous discrepancy between immune-related gene signature and sTIL findings. Our data also suggests that the poor prognosis associated with lack of infiltrating immune cells can be partly overcome by the concomitant administration of H with chemotherapy. mTIL signatures, specifically CD45, cytoxic, and T cells, were prognostically associated with improved outcome in patients receiving chemotherapy without concurrent trastuzumab. Understanding the role of the immune system in response to H will require a higher degree of granularity than can be achieved by histological quantification of TILs. Further studies are needed to validate the significance of mTIL signatures as predictive or prognostic biomarker in HER+ patients.

Citation Format: Chumsri S, Serie DJ, Mashadi-Hossein A, Tenner KS, Lauttia SL, Moreno-Aspitia A, McLaughlin SA, Nassar A, Warren S, Danaher P, Colon-Otero G, Lindman H, Joensuu H, Perez EA, Thompson EA. Prognostic value of molecular tumor infiltrating lymphocyte (mTIL) signatures in HER2-positive breast cancer patients in N9831 and FinHer/FinXX trials [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD5-06.

Circulating Serum miRNAs as Diagnostic Markers for Colorectal Cancer

AIM

The study was designed to assess the possibility of using circulating miRNAs (serum miRNAs) as diagnostic biomarkers in colorectal cancer (CRC) and to identify their possibility as candidates for targeted therapy.

METHODS

The study involved two sample sets: 1- a training set which included 90 patients with colorectal related disease (30 with CRC, 18 with inflammatory bowel disease (IBD), 18 with colonic polyps (CP) and 24 with different colonic symptoms but without any colonoscopic abnormality who were enrolled as control group) and 2- a validation set which included 100 CRC patients. Serum miRNAs were extracted from all subjects to assess the expression profiles for the following miRNAs (miR-17, miR-18a, miR-19a, miR-19b, miR-20a, miR-21, miR-146a, miR-223, miR-24, miR-454, miR-183, miR-135a, miR- 135b and miR- 92a) using the custom miScript miRNA PCR-based sybergreen array. The area under the receiver operating characteristic curve (AUC) was used to evaluate the diagnostic performance of the studied miRNAs for colorectal cancer diagnosis.

RESULTS

Data analysis of miRNA from the training set showed that; compared to control group, only miR-19b was significantly up-regulated in patients with IBD group (fold change = 5.24, p = 0.016), whereas in patients with colonic polyps, miR-18a was significantly up-regulated (fold change = 3.49, p-value = 0.018). On the other hand, miR-17, miR-19a, miR-20a and miR-223 were significantly up-regulated (fold change = 2.35, 3.07, 2.38 and 10.35; respectively and p-value = 0.02, 0.015, 0.017 and 0.016; respectively in CRC patients. However, the validation set showed that only miR-223 was significantly up-regulated in CRC patients (fold change = 4.06, p-value = 0.04).

CONCLUSION

Aberrant miRNA expressions are highly involved in the cascade of colorectal carcinogenesis. We have found that (miR-17, miR-19a, miR-20a and miR-223) could be used as diagnostic biomarkers for CRC. On the other hand, miR-19b and miR-18a could be used as diagnostic biomarkers for CP and IBD respectively.

Effect of vitamin D replacement on maternal and neonatal outcomes: a randomised controlled trial in pregnant women with hypovitaminosis D. A protocol

INTRODUCTION

The vitamin D recommended doses during pregnancy differ between societies. The WHO guidelines do not recommend routine prenatal supplementation, but they underscore the fact that women with the lowest levels may benefit most. The effects of routine supplementation during pregnancy on maternal and neonatal clinical outcomes have not been investigated in the Middle East, where hypovitaminosis D is prevalent. Our hypothesis is that in Middle Eastern pregnant women, a vitamin D dose of 3000 IU/day is required to reach a desirable maternal 25-hydroxyvitamin D [25(OH)D] level, and to positively impact infant bone mineral content (BMC).

METHODS AND ANALYSIS

This is a multicentre blinded randomised controlled trial. Pregnant women presenting to the Obstetrics and Gynaecology clinics will be approached. Eligible women will be randomised to daily equivalent doses of cholecalciferol, 600 IU or 3000 IU, from 15 to 18 weeks gestation until delivery. Maternal 25(OH)D and chemistries will be assessed at study entry, during the third trimester and at delivery. Neonatal anthropometric variables and 25(OH)D level will be measured at birth, and bone and fat mass assessment by dual-energy X-ray absorptiometry scan at 1 month. A sample size of 280 pregnant women is needed to demonstrate a statistically significant difference in the proportion of women reaching a 25(OH)D level ≥ 50 nmol/L at delivery, and a difference in infant BMC of 6 (10)g, for a 90% power and a 2.5% level of significance. The proportions of women achieving a target 25(OH)D level will be compared between the two arms, using χ(2). An independent t test will be used to compare mean infant BMC between the two arms. The primary analysis is an intention-to-treat analysis of unadjusted results.

ETHICS AND DISSEMINATION

The protocol has been approved by the Institutional Review Board at the American University of Beirut-Lebanon (IM.GEHF.22). The trial results will be published in peer-reviewed medical journals and presented at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT02434380.

Comparing Normothermic Machine Perfusion Preservation With Different Perfusates on Porcine Livers From Donors After Circulatory Death

The utilization of normothermic machine perfusion (NMP) may be an effective strategy to resuscitate livers from donation after circulatory death (DCD). There is no consensus regarding the efficacy of different perfusates on graft and bile duct viability. The aim of this study was to compare, in an NMP porcine DCD model, the preservation potential of three different perfusates. Twenty porcine livers with 60 min of warm ischemia were separated into four preservation groups: cold storage (CS), NMP with Steen solution (Steen; XVIVO Perfusion Inc., Denver, CO), Steen plus red blood cells (RBCs), or whole blood (WB). All livers were preserved for 10 h and reperfused to simulate transplantation for 24 h. During preservation, the NMP with Steen group presented the highest hepatocellular injury. At reperfusion, the CS group had the lowest bile production and the worst hepatocellular injury compared with all other groups, followed by NMP with Steen; the Steen plus RBC and WB groups presented the best functional and hepatocellular injury outcomes, with WB livers showing lower aspartate aminotransferase release and a trend toward better results for most parameters. Based on our results, a perfusate that contains an oxygen carrier is most effective in a model of NMP porcine DCD livers compared with Steen solution. Specifically, WB-perfused livers showed a trend toward better outcomes compared with Steen plus RBCs.

The role of NADPH-derived reactive oxygen species production in the pathogenesis of endometriosis: a novel mechanistic approach

Endometriosis is defined as endometriotic tissue growing outside the uterine cavity. It is a common gynecological disorder in women of reproductive age and is associated with chronic pelvic pain and infertility. Despite several studies and theories to explain its cause, the exact pathogenesis of endometriosis remains unclear. Retrograde menstruation is the most plausible theory, however, it is not exclusive. The disparity between the actual prevalence of retrograde menstruation and the prevalence of endometriosis suggests that other factors may determine the susceptibility to endometriosis development. Oxidative stress has been associated with endometriosis. This study aimed to explore the role of NADPH oxidase family in the production of reactive oxygen species (ROS) and to determine whether ROS induce the proliferation of endometriotic implants via mammalian target of rapamycin (mTOR) signaling. Anonymous endometriotic tissue samples were collected from women undergoing laparoscopy for endometriosis. The samples were stained with dihydroethidium and fluorescent images of the slides were taken to detect ROS production. After extraction of RNA from the samples and c-DNA generation, quantitative real-time PCR, protein extraction and Western blot were performed to study gene and protein expression of NADPH oxidase 1 (NOX 1), mTOR and fibronectin. The results showed an increase in ROS levels and NOX 1 gene and protein expression in the endometriotic tissues compared to the normal surrounding tissue control. Also, mTOR and fibronectin, gene expression was found to be increased. Up regulation of NOX at gene and protein level leads to increased production of ROS in the endometriotic tissue, which in turn causes proliferation of the ectopic tissue via alteration of the mTOR signaling pathway. Increased fibronectin gene expression points towards tissue injury in endometriosis as compared to the normal surrounding tissue. This manuscript adds a new insight into the pathogenesis of endometriosis and serves as a background for development of new treatments for the disease-associated pain and infertility.

The cytological diagnosis of a 'benign thyroid lesion': is it a real safe diagnosis for the patient?

OBJECTIVE

In fine needle aspiration cytology (FNAC), the category of benign thyroid lesions (BTL), which constitutes 65-70% of all thyroid FNAC, and can be correctly diagnosed by morphology alone, is an important entity. A diagnosis of BTL denotes a lesion managed with follow-up unless found in conjunction with compressive symptoms. Although this diagnosis can be quite simple, there are cases in which the scant cellular or colloid component may pose diagnostic issues. Herein, we describe the experiences of evaluating BTL at two large academic institutions. We evaluated the clinical importance of a correct diagnosis of BTL to define the exact inherent risk of a false-negative result (FNR).

METHODS

From January 2008 through to June 2013, 506 (3.6%) out of 15 850 patients with BTL underwent surgery. All nodules were sampled under sonographic guidance (US) and processed either with liquid-based cytology (LBC), Diff-Quik® smears or alcohol-Papanicolaou staining methods.

RESULTS

The histological follow-up of 506 BTL series included 493 benign and 13 malignant lesions. The latter group included four follicular carcinomas (FC), two classic variants of papillary thyroid carcinoma (PTC), one macrofollicular PTC and six follicular variants of PTC (FVPC). The malignancy rate for the BTL category was 2.5%.

CONCLUSIONS

When diagnosed by expert cytopathologists, BTL represents a robust diagnosis and might reduce the number of FNR. Additional diagnostic experience and a large case series could enable cytopathologists to recognise all the morphological entities of BTL. An important additional aid is the extensive sampling of the lesions to reduce issues related to a low cellularity.

A review of the risks and consequences of adolescent pregnancy

OBJECTIVE

To evaluate the risks and consequences of young maternal age on both the mother and the newborn.

STUDY DESIGN

A comprehensive literature review on the risks and consequences of adolescent pregnancy was performed.

RESULTS

Young maternal age is associated with an increased risk of maternal anemia, infections, eclampsia and preeclampsia, emergency cesarean delivery, postpartum depression and inadequate breastfeeding initiation. Infants of teenage mothers are more likely to be premature and have a low birth weight, and are at an increased risk for respiratory distress syndrome and autism later in life.

CONCLUSIONS

Adolescent pregnancy is a prevalent phenomenon associated with increased risks of both maternal and neonatal complications during and after pregnancy. Being aware of such adverse outcomes is imperative to improving prenatal and perinatal care. Pregnancy progression can also be influenced by the mother's culture, environment, and economic status; advancement in which may be a possible course for future improvement.

Intrahepatic blood flow redistribution after temporary occlusion of the middle hepatic vein during right lobe liver donation: report of a case

INTRODUCTION

One of the critical factors that influence graft function after live donor liver transplantation is the presence or absence of global or sectorial liver congestion. Many authors advocate for routine middle hepatic vein (MHV) reconstruction because it is often difficult to determine when the MHV or one of its major branches have functional significance. Predictive tests to assess hemodynamic and functional significance of the MHV and its tributaries are still under study.

CASE REPORT

We have described a novel intraoperative manipulation and Doppler ultrasonographic evaluation that led to the decision to include the MHV with the right lobe graft.

Lithium attenuates lipopolysaccharide-induced hypothermia in rats

BACKGROUND

Changes in body temperature are common features among patients with sepsis and septic shock. Similarly, systemic administration of bacterial endotoxin (lipopolysaccharide, LPS) to rats leads to an initial hypothermia followed by elevation in body temperature. These changes in body temperature are accompanied by increased levels of prostaglandin E2 (PGE2) in the hypothalamus.

OBJECTIVE

This study examined the effects of lithium and SB216763 - two different glycogen synthase kinase (GSK)-3 inhibitors - on LPS-induced changes in body temperature and hypothalamic PGE2 levels in endotoxemic rats.

MATERIALS AND METHODS

Endotoxemia was induced by intraperitoneal injection of LPS (10 mg/kg). Lithium (100 mg/kg) and SB216763 (5 mg/kg) were administered at 2 h before LPS. Body temperature and mortality were monitored during 48 h after LPS injection. In another protocol, rats were sacrificed at 2 h post LPS injection and then, blood, liver and hypothalamus were extracted for inflammatory mediators determination.

RESULTS

Lithium but not SB216763 significantly reduced LPS-induced hypothermia, while both compounds did not alter the subsequent elevation in body temperature. Moreover, only lithium significantly reduced hypothalamic PGE2 levels. On the other hand, both compounds significantly reduced plasma, hepatic and hypothalamic tumor necrosis factor-α and decreased plasma PGE2 levels. Both compounds did not alter LPS-induced mortality.

CONCLUSIONS

These results suggest that the attenuation of LPS-induced hypothermia by lithium may derive from its reduction of hypothalamic PGE2 levels.

Combined intestine and kidney transplantation in a patient with encapsulating peritoneal sclerosis: case report

Encapsulating peritoneal sclerosis (EPS) is a rare but devastating complication of peritoneal dialysis characterized by fibrosis and calcification of the intestine that, in severe cases, can progress to intestinal failure and total parenteral nutrition dependency. Medical and surgical interventions carry a poor prognosis in these patients. We describe a case of a 36-year-old female with end-stage kidney disease and severe EPS not amenable to surgical intervention who underwent a combined intestinal and kidney transplantation. At 3 years posttransplantation, the patient has normal intestinal and kidney function. This represents, to our knowledge, the first report of severe EPS and end-stage kidney disease treated with a combined transplant.

Reduced intensity conditioning is effective for hematopoietic SCT in dyskeratosis congenita-related BM failure

BM failure (BMF) is a major and frequent complication of dyskeratosis congenita (DKC). Allogeneic hematopoietic SCT (allo-HSCT) represents the only curative treatment for BMF associated with this condition. Transplant-related morbidity/mortality is common especially after myeloablative conditioning regimens. Herein, we report nine cases of patients with DKC who received an allo-SCT at five different member centers within the Eastern Mediterranean Blood and Marrow Transplantation Registry. Between October 1992 and February 2011, nine DKC patients (male, 7 and female, 2), with a median age at transplantation of 19.1 (4.9-31.1) years, underwent an allo-HSCT from HLA-matched, morphologically normal-related donors (100%). Preparative regimens varied according to different centers, but was reduced intensity conditioning (RIC) in eight patients. Graft source was unstimulated BM in five cases (56%) and G-CSF-mobilized PBSCs in four (44%) cases. The median stem cell dose was 6.79 (2.06-12.4) × 10(6) cells/kg body weight. GVHD prophylaxis consisted of CsA in all nine cases; MTX or mycophenolate mofetil were added in five (56%) and two (22%) cases, respectively. Anti-thymocyte globulin was administered at various doses and scheduled in four (44%) cases. Median time-to-neutrophil engraftment was 21 (17-27) days. In one case, late graft failure was noted at 10.4 months post allo-HSCT. Only one patient developed grade II acute GVHD (11%). Extensive chronic GVHD was reported in one case, whereas limited chronic GVHD occurred in another four cases. At a median follow-up of 61 (0.8-212) months, seven (78%) patients were still alive and transfusion independent. One patient died of metastatic gastric adenocarcinoma and graft failure was the cause of death in another patient. This study suggests that RIC preparative regimens are successful in inducing hematopoietic cell engraftment in patients with BMF from DKC. Owing to the limited sample size, the use of registry data and heterogeneity of preparative as well as GVHD prophylaxis regimens reported in this series, we are unable to recommend a particular regimen to be considered as the standard for patients with this disease.

Abstract P5-01-08: Complex fibroadenoma is not an independent risk marker for breast cancer

Background: Fibroadenoma (FA) is a relatively common benign breast tumor that can occur in women of any age, with a peak incidence during the second and third decades. The only previous study of this lesion reported that FAs are associated with a 2.2 times increased risk of developing invasive breast cancer (BC) compared to matched controls [1]. This relative risk may increase to 3.1 among patients with complex FA, and remains elevated for decades after diagnosis. However, this study did not thoroughly account for other forms of concomitant risk factors. Our investigative team sought to examine breast cancer risk among women with non-complex and complex FA, overall and stratified by other BC risk factors.

Materials and Methods: The study cohort included women between ages 18 to 85 in the Mayo Benign Breast Disease (BBD) Cohort who underwent excisional breast biopsy between 1967and1991 and were found to have a FA. FA was defined histologically as a combination of epithelial and stromal proliferation. Complex FA was defined as FA associated with any of the following features: sclerosing adenosis, epithelial calcifications, papillary apocrine change, and microcysts greater than 3.0 mm. The primary endpoint was a diagnosis of BC, determined using the Mayo medical record and questionnaire information from study participants. A single breast pathologist, blinded to the initial diagnosis and clinical outcome, performed pathology review. Observed vs. expected BC risk across levels of FA was assessed via standardized incidence ratios (SIRs), using age-stratified incidence rates from the Iowa Surveillance, Epidemiology, and End Results (SEER) registry. Analyses were carried out overall and within subgroups of involution status (none, partial, complete) and overall histology (non-proliferative disease [NP], proliferative disease without atypia [PDWA] or atypical hyperplasia [AH]).

Results: Of 9097 women in the Mayo BBD Cohort, FA were identified in 2139- non-complex in 1903 (20.9%) and complex in 236 (2.6%). The greatest proportion of FA occurred in the 40–69 age range. The mean ages for women with non-complex FA and complex FA were 45.7 and 50.2 years respectively. The SIR of breast cancer in the overall BBD cohort was 1.5 (95% CI [1.4–1.6]). The SIR among women with non-complex FA was 1.5 (95% CI [1.3–1.8]), and for complex FA increased to 2.41 (95% CI [1.7–3.4]). However, women with complex FA were more likely to have other concomitant high-risk histologic features such as PDWA and incomplete involution. In stratified analyses accounting for involution status and PDWA, complex FA did not demonstrate an independent increase in BC risk.

Conclusion: Complex FA does not confer an increased risk for BC beyond other established histologic features. Therefore, women with complex FA should be managed based upon a risk level consistent with the major histologic category of PDWA and/or AH.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-01-08.

Ribotyping of Erwinia chrysanthemi Strains in Relation to Their Pathogenic and Geographic Distribution

16S and 23S rRNAs from Escherichia coli were used to study the relationship among a representative collection of strains of Erwinia chrysanthemi differing in their original host and geographical origin. Phenetic analysis of restriction fragment length polymorphisms allowed the distribution of the studied strains into seven clusters. These clusters were similar to those obtained by cladistic methods and appeared to correlate well with the established pathovars and biovars but to a lesser extent with geographical distribution. Except for two groups of strains defined as tropical and temperate isolates (clusters 3 and 4, respectively), our clustering correlated well with botanical classifications of host plants. However, the rRNA groupings were shown to be more discriminative than biovar analysis. To assess the relationship between rRNA clusters and pathogenicity, 12 representative strains from different clusters were tested for pathogenicity on different plants. The two typical symptoms, maceration and wilting, were observed for these strains. The occurrence of the tobacco hypersensitivity reaction for a subset of these strains is discussed in light of recent results concerning the presence of an hrp gene. Considering symptom expression only, rather than the capacity for plant infection, strains from the same cluster were shown to induce similar symptoms in test plants. Thus, since host specificity is still quite controversial, rRNA patterns may constitute a useful tool in taxonomic and epidemiological studies of Erwinia chrysanthemi species.

Utility of glypican-3 and survivin in differentiating hepatocellular carcinoma from benign and preneoplastic hepatic lesions and metastatic carcinomas in liver fine-needle aspiration biopsies

Glypican-3 (GPC-3), a membrane-anchored heparin sulfate proteoglycan, has been shown to be expressed in approximately 80% of hepatocellular carcinoma (HCC) but not in benign hepatic lesions. Survivin, a novel inhibitor of apoptosis, and a prognostic marker, has also been expressed in HCC. We evaluated these two immunomarkers (GPC-3 and survivin) in differentiating HCC from benign and preneoplastic hepatic lesions and metastatic carcinomas, comparing them to HepPar-1 (hepatocyte paraffin-1) in liver fine-needle aspiration biopsies (FNAB).Immunohistochemistry for GPC-3, survivin and HepPar-1 was performed on 92 FNAB including HCC, hepatic cirrhosis, focal nodular hyperplasia (FNH), hepatic adenoma, dysplastic hepatic nodules and metastatic carcinomas. Immunostaining was scored as positive, if > or =10% of tumor cells stained.GPC-3 is immunoexpressed in 56.8% of HCC, but not in benign and preneoplastic hepatic lesions, or metastatic carcinomas; whereas survivin is expressed in HCC (86.4%), benign hepatic lesions (85.7%), dysplastic hepatic nodules (100%) and metastatic carcinomas (94.3%). HepPar-1 is immunoexpressed in HCC (72.7%), benign hepatic lesions (100%), dysplastic nodules (100%) and metastatic carcinomas (2.9%). The sensitivity and specificity of GPC-3, survivin and HepPar-1 for detection of HCC are 56.8 and 100%, 86.4 and 6.3%, 72.7 and 70.8%, respectively.GPC-3 is a reliable and more specific immunohistochemical marker than survivin for the diagnosis of HCC in FNAB. HepPar-1, although a more sensitive marker than GPC-3, has a lower specificity for detection of HCC. Our data supports the potentially significant diagnostic utility of GPC-3 in FNABs in differentiating primary malignant from benign and preneoplastic liver lesions, and metastatic carcinomas.