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    PublicationOpen Access
    #COVID19 and #Breastcancer: a qualitative analysis of tweets
    (Multidisciplinary Digital Publishing Institute (MDPI), 2022) Naganathan, G.; Cleland, J.; Reel, E.; Cil, T.; Bilgen, İdil; School of Medicine
    Rapid and efficient communication regarding quickly evolving medical information was paramount for healthcare providers and patients throughout the COVID-19 pandemic. Over the last several years, social media platforms such as Twitter have emerged as important tools for health promotion, virtual learning among healthcare providers, and patient support. We conducted a qualitative thematic content analysis on tweets using the hashtags #BreastSurgery, #BreastCancer, #BreastOncology, #Pandemic, and #COVID19. Advocacy organizations were the most frequent authors of tweets captured in this dataset, and most tweets came from the United States of America (64%). Seventy-three codes were generated from the data, and, through iterative, inductive analysis, three major themes were developed: patient hesitancy and vulnerability, increased efforts in knowledge sharing, and evolving best practices. We found that Twitter was an effective way to share evolving best practices, education, and collective experiences among key stakeholders. As Twitter is increasingly used as a tool for health promotion and knowledge translation, a better understanding of how key stakeholders engage with healthcare-related topics on the platform can help optimize the use of this powerful tool.
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    18F-FDG PET/CT imaging in a patient with a rare diagnosis of sarcomatoid malignant peritoneal mesothelioina
    (Lippincott Williams & Wilkins, 2013) Tokmak, Handan; Demirkol, Onur M.; Kaban, Kerim; N/A; Mandel, Nil Molinas; Dilege, Şükrü; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 194197; 122573
    Malignant peritoneal mesothelioma is an uncommon but deadly disease arising from serosal surfaces of the peritoneum. Asbestos exposure is the most recognized risk factor. We report a case of diffuse, sarcomatoid malignant peritoneal mesothelioma who presented to the hospital with abdominal pain. The patient had an abdominal MRI scan as initial scanning which demonstrated nonspecific findings suspected of peritoneal carcinomatosis. The patient was admitted to our department for the metabolic characterization of the lesions with F-18-FDG PET/CT imaging and the diagnosis of the primary malignancy. F-18-FDG PET/CT imaging revealed diffusely increased metabolic activity throughout the peritoneum and the histopathological features were compatible with sarcomatoid malignant peritoneal mesothelioma.
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    A case of pathologic complete response after neoadjuvant triplet chemotherapy for locally advanced colon cancer with mismatch repair enzyme proficiency
    (Via Medica, 2023) Kocak, Mehmet Zahid; Cakir, Murat; Kerimoglu, Ulku; Araz, Murat; Eryilmaz, Melek Karakurt; Artac, Mehmet; Yumuk, Perran Fulden; School of Medicine
    Patients with potentially resectable colon cancer and expected to have negative margins should undergo resection rather than neoadjuvant chemotherapy. Recent studies have suggested that neoadjuvant immunotherapy may be an option for tumors with mismatch repair enzyme deficiency (dMMR), but standard treatment for locally advanced colon cancer with mismatch repair enzyme proficiency (pMMR) is still unclear. A 37-year-old male patient was diagnosed with clinical stage IIIC (T4b N1a M0) transverse colon cancer. Mismatch repair proteins were proficient. After 3 cycles of oxaliplatin (85 mg/m(2), day 1), irinotecan (150 mg/m2, IV, day 1), leucovorin (200 mg/m(2), IV, day 1), and 5-fluorouracil (3000 mg/m(2), 46 hours of continuous infusion initiating from day 1), there was a remarkable reduction in the tumoral mass on the abdominal computed tomography. A right hemicolectomy was performed. A pathologic complete response was obtained. Although there is no consensus on which patients are suitable for neoadjuvant therapy in pMMR locally advanced colon cancer, triplet chemotherapy may be a reasonable option in selected patients.
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    A population-based validation of the IGCCCG update consortium for survival in metastatic non-seminoma testis cancer
    (Oxford Univ Press, 2024) Incesu, Reha-Baris; Morra, Simone; Scheipner, Lukas; Barletta, Francesco; Baudo, Andrea; Garcia, Cristina Cano; Tappero, Stefano; Piccinelli, Mattia Luca; Tian, Zhe; Saad, Fred; Shariat, Shahrokh F.; de Cobelli, Ottavio; Terrone, Carlo; Chun, Felix K. H.; Carmignani, Luca; Briganti, Alberto; Ahyai, Sascha; Longo, Nicola; Tilki, Derya; Graefen, Markus; Karakiewicz, Pierre, I; Tilki, Derya; School of Medicine; Koç University Hospital
    Background: In 2021, the International Germ Cell Cancer Collaborative Group (IGCCCG) Update Consortium reported improved overall survival (OS) rates in a modern cohort of metastatic non-seminoma testis cancer patients within each of the IGCCCG prognosis groups (96% in good vs. 89% in intermediate vs. 67% in poor), compared to the previous IGCCCG publication (92% in good vs. 80% in intermediate vs. 48% in poor). We hypothesized that a similar survival improvement may apply to a contemporary North-American population-based cohort of non-seminoma testis cancer patients. Patients and Methods: The Surveillance, Epidemiology, and End Results (SEER) database (2010-2018) was used. Kaplan-Meier plots and multivariable Cox regression models tested the effect of IGCCCG prognosis groups on overall mortality (OM). Results: Of 1672 surgically treated metastatic non-seminoma patients, 778 (47%) exhibited good vs. 251 (15%) intermediate vs. 643 (38%) poor prognosis. In the overall cohort, five-year OS rate was 94% for good prognosis vs. 87% for intermediate prognosis vs. 65% for poor prognosis. In multivariable Cox regression models predicting OM, intermediate (Hazard ratio [HR] 2.4, 95% confidence interval [CI] 1.4-3.9, P < 0.001) and poor prognosis group (HR 6.6, 95% CI 1.0-1.0, P < 0.001) were independent predictors of higher OM, relative to good prognosis group. Conclusions: The survival improvement reported by the IGCCCG Update Consortium is also operational in non-seminoma testis cancer patients within the most contemporary SEER database. This observation indicates that the survival improvement is not only applicable to centres of excellence, but also applies to other institutions at large.
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    A Post-International Gastrointestinal Cancers’ Conference (IGICC) position statements
    (DOVE MEDICAL PRESS LTD, 2024) Yalcin, Suayib; Kaseb, Ahmed Omar; Peynircioglu, Bora; Cantasdemir, Murat; Hurmuz, Pervin; Dorul, Ahmet Bulent; Bozkurt, Murat Fani; Abali, Huseyin; Akhan, Okan; Simsek, Halis; Sahin, Berksoy; Aykan, Faruk N.; Yucel, Idris; Philip, Philip; Laçin, Şahin; Tellioğlu, Gürkan; Selçukbiricik, Fatih; Çil, Barbaros Erhan; School of Medicine; Koç University Hospital
    Hepatocellular carcinoma (HCC), the most prevalent liver tumor, is usually linked with chronic liver diseases, particularly cirrhosis. As per the 2020 statistics, this cancer ranks 6th in the list of most common cancers worldwide and is the third primary source of cancer-related deaths. Asia holds the record for the highest occurrence of HCC. HCC is found three times more frequently in men than in women. The primary risk factors for HCC include chronic viral infections, excessive alcohol intake, steatotic liver disease conditions, as well as genetic and family predispositions. Roughly 40-50% of patients are identified in the late stages of the disease. Recently, there have been significant advancements in the treatment methods for advanced HCC. The selection of treatment for HCC hinges on the stage of the disease and the patient's medical status. Factors such as pre-existing liver conditions, etiology, portal hypertension, and portal vein thrombosis need critical evaluation, monitoring, and appropriate treatment. Depending on the patient and the characteristics of the disease, liver resection, ablation, or transplantation may be deemed potentially curative. For inoperable lesions, arterially directed therapy might be an option, or systemic treatment might be deemed more suitable. In specific cases, the recommendation might extend to external beam radiation therapy. For all individuals, a comprehensive, multidisciplinary approach should be adopted when considering HCC treatment options. The main treatment strategies for advanced HCC patients are typically combination treatments such as immunotherapy and anti-VEGFR inhibitor, or a combination of immunotherapy and immunotherapy where appropriate, as a first-line treatment. Furthermore, some TKIs and immune checkpoint inhibitors may be used as single agents in cases where patients are not fit for the combination therapies. As second -line treatments, some treatment agents have been reported and can be considered.
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    A systematic review of the efficacy and toxicity of brachytherapy boost combined with external beam radiotherapy for nonmetastatic prostate cancer
    (Elsevier, 2023) Slevin, F; Zattoni, F; Checcucci, E; Cumberbatch, MGK; Nacchia, A; Cornford, P; Briers, E; De Meerleer, G; De Santis, M; Eberli, D; Gandaglia, G; Gillessen, S; Grivas, N; Liew, M; Linares Espinós, EE; Oldenburg, J; Oprea-Lager, DE; Ploussard, G; Rouvière, O; Schoots, IG; Smith, EJ; Stranne, J; Smith, CT; Van Den Bergh, RCN; Van Oort, IM; Wiegel, T; Yuan, CY; Van den Broeck, T; Henry, AM; Tilki, Derya; School of Medicine; Koç University Hospital
    Context: The optimum use of brachytherapy (BT) combined with external beam radiotherapy (EBRT) for localised/locally advanced prostate cancer (PCa) remains uncertain. Objective: To perform a systematic review to determine the benefits and harms of EBRT-BT. Evidence Acquisition: Ovid MEDLINE, Embase, and EBM Reviews-Cochrane Central Register of Controlled Trials databases were systematically searched for studies published between January 1, 2000 and June 7, 2022, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Eligible studies compared low- or high-dose-rate EBRT-BT against EBRT ± androgen deprivation therapy (ADT) and/or radical prostatectomy (RP) ± postoperative radiotherapy (RP ± EBRT). The main outcomes were biochemical progression-free survival (bPFS), severe late genitourinary (GU)/gastrointestinal toxicity, metastasis-free survival (MFS), cancer-specific survival (CSS), and overall survival (OS), at/beyond 5 yr. Risk of bias was assessed and confounding assessment was performed. A meta-analysis was performed for randomised controlled trials (RCTs). Evidence Synthesis: Seventy-three studies were included (two RCTs, seven prospective studies, and 64 retrospective studies). Most studies included participants with intermediate-or high-risk PCa. Most studies, including both RCTs, used ADT with EBRT-BT. Generally, EBRT-BT was associated with improved bPFS compared with EBRT, but similar MFS, CSS, and OS. A meta-analysis of the two RCTs showed superior bPFS with EBRT-BT (estimated fixed-effect hazard ratio [HR] 0.54 [95% confidence interval {CI} 0.40-0.72], p < 0.001), with absolute improvements in bPFS at 5-6 yr of 4.9-16%. However, no difference was seen for MFS (HR 0.84 [95% CI 0.53-1.28], p = 0.4) or OS (HR 0.87 [95% CI 0.63-1.19], p = 0.4). Fewer studies examined RP ± EBRT. There is an increased risk of severe late GU toxicity, especially with low-dose-rate EBRT-BT, with some evidence of increased prevalence of severe GU toxicity at 5-6 yr of 6.4-7% across the two RCTs. Conclusions: EBRT-BT can be considered for unfavourable intermediate/high-risk localised/locally advanced PCa in patients with good urinary function, although the strength of this recommendation based on the European Association of Urology guideline methodology is weak given that it is based on improvements in biochemical control. Patient Summary: We found good evidence that radiotherapy combined with brachytherapy keeps prostate cancer controlled for longer, but it could lead to worse urinary side effects than radiotherapy without brachytherapy, and its impact on cancer spread and patient survival is less clear.
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    Acinar cell induced autolysis is a frequent occurrence in Cytolyt-fixed pancreatic fine needle aspiration specimens: an analysis of 157 cytology samples
    (Wiley, 2021) Alwelaie, Yazeed; Point du Jour, Kimberly S.; Pandya, Sonal; Goodman, Abigail L.; Centeno, Barbara A.; Reid, Michelle D.; N/A; Adsay, Nazmi Volkan; Faculty Member; School of Medicine; Koc University Hospital; 286248
    Background Although 10% formalin is a standard preservative in pancreatic FNAs, the effect of CytoLyt on pancreatic tissue preservation has not been systematically explored. Methods Smears and cell blocks from CytoLyt-fixed (CF-CBs) and formalin-fixed (FF-CBs) pancreatic FNAs were blindly reviewed without knowledge of the fixative used, and the presence of tissue/tumor autolysis was noted. Controls included FF-CBs from pancreatic FNAs, CF-CBs from nonpancreatic FNAs, and 4 pancreatic FNAs with matched CF-CBs and FF-CBs. Results We found that 62 of 85 (73%) pancreatic FNAs with CF-CBs showed significant autolysis, which was most pronounced in acinar cells and/or tumor cells with benign acinar cells in the background, compared with 2 of 46 (4%) FF-CBs (P < .0001) and 3 of 26 (12%) CF-CBs from nonpancreatic FNAs (73% vs 12%; P < .0001). Of the 4 pancreatic FNAs with matched CF-CBs and FF-CBs, all 4 CF-CBs showed marked autolysis versus none of the matched FF-CBs. Of the 23 (27%) pancreatic FNAs with CF-CBs that did not show autolysis, 10 had no acinar cells, and 7 had only minute tissue fragments on CB. Conclusion While CytoLyt is a useful fixative for nonpancreatic FNAs it is a suboptimal fixative for pancreatic FNAs and is associated with tissue/tumor autolysis in the majority of cases, influencing morphologic evaluation, and potentially immunocytochemical staining. Autolysis appears to be due to acinar enzymes whose effect is likely interrupted/inhibited by formalin fixation. Cytopathologists and cytotechnologists should be mindful of this pitfall and should avoid using CytoLyt as a fixative for pancreatic FNAs.
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    PublicationOpen Access
    Activated leukocyte cell adhesion molecule regulates the interaction between pancreatic cancer cells and stellate cells
    (Spandidos Publications, 2016) Zhang, Wei-Wei; Zhan, Shu-Hui; Geng, Chang-Xin; Sun, Xin; Kleeff, Joerg; Xie, Xiang-Jun; N/A; Erkan, Murat Mert; Faculty Member; School of Medicine; 214689
    Activated leukocyte cell adhesion molecule (ALCAM/CD166) is a transmembrane glycoprotein that is involved in tumor progression and metastasis. In the present study, the expression and functional role of ALCAM in pancreatic cancer cells and pancreatic stellate cells (PSCs) was investigated. Tissue specimens were obtained from patients with pancreatic ductal adenocarcinoma (n=56) or chronic pancreatitis (CP; n=10), who underwent pancreatic resection, and from normal pancreatic tissue samples (n=10). Immunohistochemistry was used to analyze the localization and expression of ALCAM in pancreatic tissues. Subsequently, reverse transcription-quantitative polymerase chain reaction and immunoblotting were applied to assess the expression of ALCAM in pancreatic cancer Panc-1 and T3M4 cells, as well as in PSCs. An enzyme-linked immunosorbent assay was used to measure ALCAM levels in cell culture medium stimulated by hypoxia, tumor necrosis factor (TNF)- and transforming growth factor-. Silencing of ALCAM was performed using ALCAM small interfering (si)RNA and immunocytochemistry was used to analyze the inhibition efficiency. An invasion assay and a cell interaction assay were performed to assess the invasive ability and co-cultured adhesive potential of Panc-1 and T3M4 cells, as well as PSCs. Histologically, ALCAM expression was generally weak or absent in pancreatic cancer cells, but was markedly upregulated in PSCs in pancreatic cancer tissues. ALCAM was highly expressed in PSCs from CP tissues and PSCs surrounding pancreatic intraepithelial neoplasias, as well as in pancreatic cancer cells. ALCAM mRNA was highly expressed in PSCs, with a low to moderate expression in T3M4 and Panc-1 cells. Similar to the mRNA expression, immunoblotting demonstrated that ALCAM protein levels were high in PSCs and T3M4 cells, but low in Panc-1 cells. The expression of TNF- increased, while hypoxia decreased the secretion of ALCAM in pancreatic cancer Panc-1 and T3M4 cells, and also in PSCs. Silencing of ALCAM by siRNA revealed no significant alteration in the invasion of pancreatic cancer cells, however, it inhibited the invasive ability of PSCs, and decreased the interaction between Panc-1 cells and PSCs. In conclusion, ALCAM is upregulated in PSCs of pancreatic cancer tissues, suggesting a potential role of ALCAM in regulating pancreatic cancer cell-PSC interactions.
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    Adjuvant chemoradiotherapy after D2 resection in gastric cancer: a single-center observational study
    (Springer, 2015) Saglam, Esra Kaytan; Yucel, Serap; Saglam, Sezer; Asoglu, Oktar; Yamaner, Sumer; Oral, Ethem N.; Kizir, Ahmet; Kapran, Yersu; Sakar, Burak; Akyuz, Ali; Gulluoglu, Mine; N/A; Balık, Emre; Buğra, Dursun; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 18758; 1758
    Previous studies demonstrated survival benefits in association with the addition of chemoradiotherapy after surgery in gastric cancer. This study aimed to examine the efficacy in terms of loco-regional control and survival and safety of 5-FU-based adjuvant chemoradiotherapy after D2 curative surgery. This study included 228 patients (81 female, 147 male) treated for gastric cancer with curative surgery plus adjuvant chemoradiotherapy. Majority of the patients underwent at least D2 lymph node resection. Median three cycles of fluorouracil chemotherapy were administered, and 45-Gy radiotherapy was delivered at 1.8 Gy/fraction concomitantly during the second cycle of chemotherapy. Local control, regional control, distant metastasis and overall survival rates were estimated. The median age of the patients was 54 years (range 25-74 years). The most common grade III toxicities were nausea (10 %) and neutropenia (9 %). During radiotherapy, grade IV local skin reaction occurred in one patient. Median duration of follow-up was 47 months. Local, regional and distant recurrence developed in 9 (4 %), 41 (18 %) and 45 (20 %) patients, respectively. Overall 5-year survival rate was 57.2 %, and disease-free 5-year survival rate was 53.8 %. Multivariate analysis identified less than 15 lymph node involvement as an independent predictor of better survival (p < 0.001). Concomitant 5-FU-based chemoradiotherapy seems to be an effective and tolerable adjuvant regimen on local control and survival in curatively resected node-positive stomach cancer, particularly when combined with D2 resection.
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    PublicationOpen Access
    Adjuvant chemotherapy for gastric cancer in elderly patients has same benefits as in younger patients
    (Medknow Publications, 2018) Karaca, Mustafa; Tural, Deniz; Koçoğlu, Hakan; Bilgetekin, İrem; Özet, Ahmet; N/A; Selçukbiricik, Fatih; Faculty Member; School of Medicine
    Objective: The age-adjusted mortality rate due to gastric cancer was reported to increase with age. This study aims to investigate the results of adjuvant chemotherapy in patients aged 65 years or older comparing with younger patients and focusing on its impact on survival. Materials and Methods: A total of 406 patients with nonmetastatic gastric cancer that consisted of 283 patients younger than 65 years (range: 23-64 years) and 123 patients 65 years of age or older (range: 65-75 years) were retrospectively evaluated. Categorical and continuous variables were summarized using the descriptive statistics and compared with Chi-square and Mann-Whitney U-tests, respectively. Cancer-specific survival rates were estimated by the Kaplan-Meier method. Results: Median age at diagnosis was 58 years (range: 23-75 years). There was no significant difference in gender, tumor localization in the stomach (cardia/noncardia), tumor histology, perineural invasion, lymphovascular invasion, histopathological characteristics of the tumor, and tumor stage between groups. No significant difference was detected in survival between groups. The median survivals were 20.8 months (range: 17-24.6) in patients younger than 65 years and 19.5 months (range: 14.8-24.1) in patients 65 years of age or older (P = 0.9). Conclusions: We showed that adjuvant chemotherapy in elderly patients with gastric cancer has same effectiveness as nonelderly patients. However, further well-designated prospective studies are needed to confirm these findings.