An Online Distance Tracker for Verification of Robotic Systems' Safety.

This paper presents an efficient method for minimum distance calculation between a robot and its environment and the implementation framework as a tool for the verification of robotic systems' safety. Collision is the most fundamental safety problem in robotic systems. Therefore, robotic system software must be verified to ensure that there are no risks of collision during development and implementation. The online distance tracker (ODT) is intended to provide minimum distances between the robots and their environments for verification of system software to inspect whether it causes a collision risk. The proposed method employs the representations of the robot and its environment with cylinders and an occupancy map. Furthermore, the bounding box approach improves the performance of the minimum distance calculation regarding computational cost. Finally, the method is applied to a realistically simulated twin of the ROKOS, which is an automated robotic inspection cell for quality control of automotive body-in-white and is actively used in the bus manufacturing industry. The simulation results demonstrate the feasibility and effectiveness of the proposed method.

Safety and efficacy of trifluridine/tipiracil in previously treated metastatic colorectal cancer: PRECONNECT Turkey.

Background: The efficacy and safety of trifluridine/tipiracil (FTD/TPI) for third-line treatment of metastatic colorectal cancer have been demonstrated. The authors present the Turkish post hoc analysis of the PRECONNECT study. Methods: An international, multicenter, single-arm, open-label, phase IIIb trial evaluating FTD/TPI in patients with ≥2 previous lines of chemotherapy for metastatic colorectal cancer was conducted. The primary end point was safety. Results: In this Turkish cohort (n = 100; eight centers), the most frequent treatment-emergent adverse event was neutropenia (48%). Median progression-free survival was 3.0 months; disease control rate was 36%; quality of life remained stable. Conclusion: Outcomes with FTD/TPI in Turkey are consistent with previous studies and confirm the efficacy and safety of FTD/TPI treatment in the third-line setting. Clinical Trial Registration: NCT03306394 (ClinicalTrials.gov).

Efficacy of trastuzumab and potential risk factors on survival in patients with HER2-positive metastatic gastric cancer.

Aim: To evaluate the efficacy of trastuzumab and potential risk factors on survival in patients with HER2-positive metastatic gastric cancer. Methods: We retrospectively included 138 patients who were given trastuzumab-based chemotherapy as first-line treatment and analyzed the relationship between clinical response rates and maintenance treatment status and survival outcomes. Results: In the whole group, the median progression-free survival and overall survival were 10.2 and 16 months, respectively. Clinical response was obtained in 79% of patients. The median overall survival was 16.9 months in follow-up group and 19.0 months in the maintenance group in patients with clinical response. Continuation of maintenance trastuzumab created a significant survival advantage (p = 0.021). Eastern Cooperative Oncology Group performance status 2 (hazard ratio [HR]: 2.02), grade 3 (HR: 1.78) and more than four metastatic lesions (HR: 1.67) were determined as risk factors for death. Conclusion: We recommend the continuation of maintenance trastuzumab in patients with clinical response, but those with identified risk factors may not benefit from treatment because life expectancy may be low.

Gastric cancer has a poor prognosis despite available treatments. Inclusive studies are still needed with real-life data. Our research retrospectively evaluated the efficacy of trastuzumab and potential risk factors on survival in patients with HER2-positive metastatic gastric cancer who received trastuzumab-based chemotherapy as first-line therapy. In total, 138 patients were included in this study. Clinical response to trastuzumab-based chemotherapy was obtained in 79% of the patients. We also divided the patients who had a clinical response into two groups according to whether they received maintenance therapy. In the present study, trastuzumab administration had compatible survival outcomes with recent studies. Continuation of trastuzumab maintenance treatment provided a survival advantage in patients with clinical response. We suppose that maintenance trastuzumab may be recommended in patients with clinical responses to the first-line treatment. Furthermore, Eastern Cooperative Oncology Group Performance Status 2, grade 3 and having more than four metastatic lesions were determined as risk factors for death. Therefore, although we recommend maintenance of trastuzumab in patients with clinical response, those with identified risk factors may not benefit from treatment.

Tyrosine kinase inhibitors in the treatment of metastatic renal cell cancer patients with early cytokine intolerance: TURCOS, a Turkish national, prospective observational study.

OBJECTIVE: Cytokines have been the mainstay of treatment in metastatic renal cell cancer (mRCC) for decades before the introduction of tyrosine kinase inhibitors (TKIs), which dramatically changed the therapeutic landscape in these patients. This observational study was designed to evaluate use of TKIs in the treatment of cytokine-intolerant mRCC patients. METHODS: A total of 151 cytokine-intolerant mRCC patients who were treated with TKIs (sunitinib, pazopanib and sorafenib) were enrolled in this prospective, non-interventional, multi-center observational study at 16 oncology centers across Turkey. Mean (SD) age was 61.3 (11.1) years and 74.8% were males. Data on duration of TKI treatment was the primary outcome measure. Additionally, overall response rate (ORR), progression free survival (PFS), overall survival (OS) and safety data were recorded. RESULTS: Median duration of treatment was 8.2 months at a median follow up of 17.9 months. ORR and disease control rate were 12.5% and 70.8%, respectively. Median PFS and OS were 7.5 months (95%CI: 6.4-10.4) and 27.3 months (95%CI: 17.6-27.3) with no significant difference among three TKI agents in terms of treatment duration, ORR, PFS and OS. The most common adverse events excluding progression-which was the protocol requirement were diarrhea (13.6%), asthenia (13.6%) and hand-foot syndrome (12.6%). Dose modifications were required in 30.5% of the patients and 15% discontinued TKIs because of toxicity. CONCLUSIONS: Our findings confirm the efficacy and safety profile of TKIs in the first-line treatment of mRCC patients intolerant to cytokine treatment. There was no significant difference among three TKI agents in terms of treatment duration, ORR, PFS and OS.Trial registration: TURCOS ClinicalTrials.gov Identifier: NCT01585974. Registered April 25, 2012.

Is SUVmax of 18F-FDG PET/CT Predictive Factor for Malignancy in Gastrointestinal Tract?

BACKGROUND: Increasing use of 18F-FDG PET/CT in cancer patients, has led to more common detection of 18F- FDG uptake in the gastrointestinal tract (GIT). AIMS: The objective of this study was to assess 18F-FDG uptake in incidental and known GIT malignancy. METHODS: A total of 6500 patients followed-up in a single and tertiary center between January 2010 and September 2016 were retrospectively reviewed. Of 2850 patients assessed with 18FDG-PET/CT, known GIT malignancy and 18F-FDG uptake cases during follow-up were included in the study. RESULTS: Of 658 patients with 18F-FDG uptake, 150 patients who underwent endoscopy were included in the study. Seventy-seven of these patients had known GIT malignancy and 73 had incidental 18F-FDG uptake. Among these 73 patients; 7 (9.6%) had malignancy, 20 (27,2%) adenoma and 24 (32.9%) inflammation that were confirmed. Endoscopy was normal in 22 (30.2%) patients. One hundred forty-three (95.3%) patients had focal and 7 (4.7%) had diffuse uptake. While no malignancy was detected in patients with diffuse uptake, 58.7% (84/143) of the patients with focal uptake presented malignancy. Mean the standardized uptake value (SUV) max values were found as 15.0 ± 10.6 (range, 3.8-56.5) in malignant disease, 10.2 ± 4.3 (range, 2.4-19.7) in adenoma, 7.3 ± 3.6 (range, 3.6-18.7) in inflammation, and 9.8 ± 4.2 (range, 3.8-19.9) in normal endoscopy groups (p < 0.001, rho = 0.378). CONCLUSION: Although this study demonstrated high probability of malignant disease with increased 18F-FDG uptake in the GIT, it would be a more appropriate approach to confirm all patients with 18F-FDG uptake through endoscopy as SUVmax values vary in a wide range.

Quality of life study of patients with unresectable locally advanced or metastatic pancreatic adenocarcinoma treated with gemcitabine+nab-paclitaxel versus gemcitabine alone: AX-PANC-SY001, a randomized phase-2 study.

BACKGROUND: Combination of gemcitabine and nab-paclitaxel has superior clinical efficacy than gemcitabine alone. Nevertheless, health-related quality of life. (QoL) associated with this combination therapy when administered at first-line in advanced pancreatic adenocarcinoma is unknown. METHODS: A total of 125 patients were randomized to combination therapy (1000 mg/m2 gemcitabine + 125 mg/m2 nab-paclitaxel) and single-agent gemcitabine (1000 mg/m2) arms to take treatment weekly for 7 of 8 weeks, and following 3 of 4 weeks, until progression or severe toxicity. Primary endpoints were three-months of definitive deterioration free percent of patients, and QoL. RESULTS: Overall QoL analyses showed that 34 and 58.3% of cases in gemcitabine and gemcitabine+nab-P arms had no deterioration in 3rd month QoL scores (p = 0.018). These proportions were 27.3 and 36.6% in 6th month assessments, respectively (p = 0.357). Median overall survivals in combination and single-agent arms were 9.92 months and 5.95 months, respectively (HR: 0.64, 95% CI: 0.42-0.86, p = 0.038). Median progression free survivals in these treatment arms were 6.28 and 3.22 months, respectively (HR: 0.58, 95% CI: 0.39-0.87, p = 0.008). Median time-to-deterioration were 5.36 vs 3.68 months, and objective response rates were 37.1% vs 23.7% (p = 0.009), respectively in combination and single-agent arms. CONCLUSIONS: Combination therapy with gemcitabine + nab-paclitaxel had better overall and progression-free survival than gemcitabine alone. Also, combination therapy showed increased response rate without toxicity or deteriorated QoL. Combination treatment with gemcitabine and nab-paclitaxel may provide significant benefit for advanced pancreatic cancer. TRIAL REGISTRATION: This study has been registered in ClinicalTrials.gov as NCT03807999 on January 8, 2019 (retrospectively registered).

Efficacy of second-line targeted agents in kras wild metastatic colorectal cancer patients who received prior targeted agent: First anti-epidermal growth factor receptor or vascular endothelial growth factor in right and left colon?

INTRODUCTION: We aimed to investigate the impact of first biological agents on second-line biological agents in kras wild-type metastatic colon patients in right and left colon. PATIENTS AND METHODS: The patients received anti-EGFR compared with anti-VEGF in right and left colon separately according to progression-free survival and overall survival in second line. RESULTS: A total of 84 patients were included in the study. In left colon, progression-free survival and overall survival were 9 and 14 months for anti-EGFR and 9 and 16 months for anti-VEGF in the second line. In right colon, progression-free survival and overall survival were 5 and 9 months for anti-EGFR and 4 and 6 months for anti-VEGF in the second line. CONCLUSIONS: Progression-free survival was higher in patients who received bevacizumab first followed by anti-EGFR than reverse sequencing in right colon. Overall survival was similar between two groups.

Biweekly cisplatin and gemcitabine with two different doses in non small cell lung cancer patients: A retrospective singlecenter experience.

PURPOSE: Non-small-cell lung cancer (NSCLC) constitutes 80-85% of all lung cancers. Patients with advanced-stage NSCLC may benefit from chemotherapy. Gemcitabine and cisplatin is a well-established therapy for this malignancy. Recently, biweekly administration is becoming more acceptable, but the most effective and tolerable dose remains unclear. The purpose of this study was to compare the toxicity and efficacy of 1000 mg/m2 gemcitabine (GEM 1000) and 1500 mg/m2 gemcitabine (GEM 1500) in combination with 50 mg/m2 cisplatin. METHODS: Gemcitabine was administered at a dose of 1000 or 1500 mg/m2 with cisplatin administered at a dose of 50 mg/m2 on day 1. The treatment was repeated every 2 weeks for a total of 4 courses. Response rates, progression-free survival (PFS), overall survival (OS) and toxicities were assessed. RESULTS: 114 patients with IIIB and IV stages of NSCLC were included. Seventy two patients (63%) received GEM 1000 and 42 (37%) received GEM 1500. The overall reponse rate (ORR), PFS and OS were 24%, 6 months and 13 months respectively in the GEM 1000 group and 36%, 6 months and 15 months in the GEM 1500 group, respectively. Grade 3-4 neutropenia and thrombocytopenia were observed in 4% of the GEM 1000 group and 9% of the GEM 1500 group (p=0.41). CONCLUSION: Biweekly administration of GEM 1000 and 1500 is a well tolerated regimen. Although the GEM 1000 group showed a lower response rate than the GEM 1500 group, PFS and OS were similar.

Comparison of survival with somatostatin analog and chemotherapy and prognostic factors for treatment in 165 advanced neuroendocrine tumor patients with Ki-67 20% or less.

The objectives of this study were to compare progression-free survival (PFS) with somatostatin analog (SSA) versus chemotherapy (CTx) in first-line therapy and to determine the patient group in which these treatments were more effective in neuroendocrine tumors (NETs) with a Ki-67 index of 20% or less. Patients who received SSA or CTx and had unresectable locally advanced and metastatic NETs with a Ki-67 index of 20% or less were retrospectively selected from 13 centers in the Turkish database between 2000 and 2015. One hundred and sixty-five patients were enrolled. The median age was 56 years and the male-to-female ratio was 1.09. Seventy-four (45%) patients were of grade 1 NET and 91 (55%) were of grade 2. SSA was given to 104 patients, whereas 61 were treated with CTx. The objective response rate after SSA was 15.4%; another 73.1% had stable disease. The objective response rate after CTx was 36.1%, and 40.9% had stable disease (P=0.008). The median PFS in SSA patients was 21 months (95% confidence interval: 12.4-29.6), and 8 months for CTx (95% confidence interval: 5.5-10.6) (P<0.001). There was no significant difference between PFS of receiving SSA and CTx in pancreatic neuroendocrine tumor (PNET) patients; however, the PFS of receiving SSA was longer in non-PNET patients (P<0.001). SSA was better treatment in advanced NET patients with a Ki-67 index of less than 5%, having a primary resected and a performance status of 0 (P<0.05). SSA may be preferred over CTx in advanced NET patients with low-to-intermediate grade.

Efficacy and safety of cetuximab plus FOLFOX in second-line and third-line therapy in metastatic colorectal cancer.

PURPOSE: To evaluate the efficacy and adverse events with cetuximab plus FOLFOX administered as second- and third-line therapy in metastatic colorectal cancer (mCRC) patients. METHODS: IPatients were administered cetuximab plus FOLFOX as second- and third-line therapy from January 2010 through October 2015. mCRC patients with wild type KRAS were alsï given irinïtecan and/ïr ïxaliplatin cïmbined with fluorïpyrimidine±bevacizumab. Tumor respïnse and survival were evaluated using RECIST and Kaplan-Meier methïd respectively. RESULTS: Sixty patients were included this study. Cetuximab plus FOLFOX was administered to 40 (66.7%) patients as second-line and to 20 (33.3%) as third-line therapy. The majority of the patients had a good ECOG performance status (PS) (0 or 1). Clinical benefit was partial plus stable disease and it was 75.0% for both of these two lines. The median progression free survival (PFS) was 7.1 months (95% CI=3.2-10.9) and 6.0 months (95% CI=2.4-9.6), in the second-and third-line (p=0.484). The median ïverall survival (ÏS) was 14.3 and 9.2 mïnths in secïnd-and third-line therapy respectively (p=0.071). The common toxicities were haematologic and gastrointestinal, mostly grade 1 and 2. CONCLUSION: The addition of cetuximab to FOLFOX was well-tolerated and had antitumor activity both in second- and third-line therapy in patients with mCRC.

The effect of the gastrectomy on survival in patients with metastatic gastric cancer: a study of ASMO.

AIM: To investigate the role of surgical resection of primary tumor on overall survival (OS) in advanced gastric cancer patients at the time of diagnosis. PATIENTS & METHODS: The survival rates of metastatic gastric cancer patients whose gastric primary tumor was resected at time of diagnosis were compared with metastatic gastric cancer patients whose primary tumor was nonresected. RESULTS: The median progression-free survival and OS in operated and nonoperated group were 10 versus 6, 14 versus 9 months, respectively (p < 0.001). In multivariate analysis, gastric resection of primary tumor, Eastern Cooperative Oncology Group performance status, second-line chemotherapy had a significant effect on OS (hazard ratio [HR]: 0.52 [95% CI: 0.38-0.71], HR: 0.57 [95% CI: 0.42-0.78], HR: 1.48 [1.09-2.01]; p ≤ 0.001, p = 0.001 and p = 0.012, respectively). CONCLUSION: Subpopulations of patients with metastatic gastric cancer might benefit from surgical removal of primary tumor.

Predicting the role of the pretreatment neutrophil to lymphocyte ratio in the survival of early triple-negative breast cancer patients.

PURPOSE: Increasing evidence supports an association between systemic inflammation and cancer development and progression. The neutrophil to lymphocyte ratio (NLR) is used as a basic parameter of systemic inflammation in some tumors. The aim of this study was to examine the association between the pretreatment NLR, disease-free survival (DFS), and overall survival (OS) in patients with early triple-negative breast cancer (TNBC). METHODS: We retrospectively studied patients diagnosed with stage I-III TNBC who had completed all phases of primary treatment from 2002 to 2013. The association between the pretreatment NLR and survival was analyzed. The difference among variables was calculated by chi-square test. OS and DFS were assessed using the Kaplan-Meier method. Multivariate Cox proportional hazards models were used to analyze the prognostic impact of clinical parameters. RESULTS: Eighty-five patients were eligible for study inclusion. There were no statistically significant differences among the pretreatment NLR and clinicopathological variables. Patients with an NLR of > 2 had significantly lower DFS (p=0.002) and OS (p=0.03) than patients with an NLR of ≤ 2. Multivariate Cox proportional hazards models showed that a higher pretreatment NLR was independently correlated with poor DFS and OS, with a hazard ratio 5.46 (95% confidence interval [CI] 1.61-18.85, p=0.006) and 2.86 (95% CI 1.04-7.86, p=0.04), respectively. CONCLUSION: Patients with early TNBC and with elevated pretreatment NLR showed poorer DFS and OS than patients without elevated NLR. However, this finding needs to be confirmed in a large prospective study.

Hepatic steatosis is associated with higher incidence of liver metastasis in patients with metastatic breast cancer; an observational clinical study.

PURPOSE: To investigate the relationship between hepatic steatosis (HS) (at the time of diagnosis) and hepatic metastasis (at the time of diagnosis and follow-up) in metastatic breast cancer (BC) patients by using computed tomography (CT). METHODS: A total of 107 metastatic BC patients who had an abdominal CT were retrospectively enrolled in this study. Patients without HS (N=79) were regarded as the control group and those with HS constituted the HS study group (N-28). RESULTS: Hepatic metastases at diagnosis and during follow-up were more common in patients with HS (p=0.018 and p=0.041, respectively) and in the premenopausal group (p<0.001 and p=0.004, respectively), whereas they were similar in patients with and without HS in the postmenopausal group (p=0.655 and p=0.656, respectively). Overall survival rates were similar in patients with and without HS (p=0.606). CONCLUSION: Hepatic metastases at diagnosis and during follow-up were more frequent in patients with HS, especially in premenopausal patients. Survival was similar in both groups.

Cutaneous melanoma in Turkey: analysis of 1157 patients in the Melanoma Turkish Study.

PURPOSE: To develop a large Turkish National Melanoma registry in order to define demographic and clinicopathologic characteristics of patients with melanoma. METHODS: The data was collected from 1635 patients with melanoma through a web-based registry system in 22 centers. Herein we present the results of 1157 patients with cutaneous melanoma. RESULTS: The patient median age was 56.4 years and 646 (55.8%) were males. The commonest subtype was superficial spreading type (357, 30.9%). The commonest primary site was the lower extremities (N=353, 30.5%). The most common Breslow thickness was 1-2 mm (361 patients, 43.5%). Only 104 (12.5%) patients had a thickness <1mm. Among 694 patients with available data, 136 (19.6%) presented with stage 4 disease while the most frequent stage was stage 3, encountered in 393 (56.6% patients). CONCLUSION: Our melanoma registry is the largest in our country providing a snapshot view of cutaneous melanoma and its care. Our patients presented with more advanced stages and they had worse prognosis compared to SEER database.

Outcome of 561 non-metastatic triple negative breast cancer patients: multi-center experience from Turkey.

PURPOSE: Triple-negative breast cancers account for 15% of breast carcinomas and, when present as early-stage disease, they are associated with higher rates of recurrence and early distant metastasis risk when compared to hormone receptor positive and human epidermal growth factor receptor (HER-2) positive breast cancers. In this study we aimed to explore the basic clinicopathological characteristics, prognostic factors and recurrence patterns of non-metastatic triple negative breast cancer patients. METHODS: In this study 561 non-metastatic triple-negative breast cancer female patients admitted to 8 different cancer centers in Turkey between 2000 and 2010 were retrospectively evaluated through their medical records, to identify the basic clinico-pathological characteristics, prognostic factors and recurrence patterns. RESULTS: The ratio of triple-negative breast cancer was 12%. The median age of patients was 48 years, of whom 311 (55.4%) were premenopausal. The majority had early-stage breast cancer at the time of diagnosis (16.8% stage I, 48.1% stage II, 35.1 % stage III) and the most commonly identified variant was invasive ductal carcinoma (84.1%). Grade II and III tumors were 27.1 and 48.5%, respectively. Adjuvant chemotherapy was administered to 90.5% of women and adjuvant radiotherapy to 41.2%. Median patient follow up was 28 months (range 3-290). During the follow up period 134 (23.8%) patients developed metastatic disease. In most of these cases, metastatic sites were bone, soft tissue, and lung. Factors affecting disease free survival (DFS) and overall survival (OS) were age (both p<0.001), lymph node involvement (both p<0.001), lymphovascular invasion (LVI) (p<0.001 and p=0.004, respectively), tumor stage (both p<0.001), adjuvant administration of anthracycline-based chemotherapy (both <0.001) and type of surgery (not significant for DFS but p=0.05 for OS). Three-year DFS and OS were 72.0 and 93.0%, respectively. CONCLUSION: Age, lymph node involvement, LVI, stage, and adjuvant chemotherapy were determined as prognostic factors for DFS and OS. The most common recurrence sites were bone, soft tissue and the lung. Further prospective randomised trials are needed to confirm the prognostic and predictive factors identified in this study.

Results of adjuvant FOLFOX regimens in stage III colorectal cancer patients: retrospective analysis of 667 patients.

OBJECTIVE: The aim of this study was to assess the use of 5-fluorouracil (5-FU), leucovorin and oxaliplatin (FOLFOX) regimens in clinical practice according to their efficacy and toxicity. METHODS: Patients who received oxaliplatin-containing regimens after curative resection for colorectal carcinoma from 10 different oncology centers between May 2004 and December 2009 were included in the study. All patients were treated with FOLFOX regimens. Patients with rectal carcinoma were also treated with chemoradiotherapy with 5-FU after 2 cycles of a FOLFOX regimen. RESULTS: The median age of the patients was 56 years (range 17-78). Of the total 667 patients, 326 were given FOLFOX-4, 232 were given modified FOLFOX-4 and 109 were given FOLFOX-6. The distribution according to disease stage was 33 patients with stage IIIA colorectal cancer, 382 patients with stage IIIB and 252 patients with stage IIIC. The most common adverse events were neutropenia (54%), nausea (36.9%), neuropathy (38.2%) and anemia (33.1%) for all grades. The median follow-up time was 23 months (range 1-79). Three-year disease-free survival and overall survival were 65 and 85.7%, respectively. CONCLUSION: The different oxaliplatin-containing 5-FU-based adjuvant chemotherapy regimens in patients with stage III colorectal cancer seemed to be at least equal in terms of efficacy regardless of the method of 5-FU administration or oxaliplatin dose.

Moxifloxacin-associated neutropenia.

A 32-y-old woman presented with pneumonia. Treatment was started with moxifloxacin. On day 2 of moxifloxacin treatment the patient developed neutropenia. After discontinuing the moxifloxacin, neutrophil counts were normal on day 4. Clinicians should be aware of the possibility of this adverse effect in patients treated with moxifloxacin.

Bevacizumab-containing chemotherapy is safe in patients with unresectable metastatic colorectal cancer and a synchronous asymptomatic primary tumor.

OBJECTIVE: Surgical resection of asymptomatic primary colorectal cancer in patients presenting with synchronous unresectable metastatic disease is controversial. Concerns and controversies remain over combining cytotoxic chemotherapy with bevacizumab in this patient population. METHODS: We identified medical records of 99 patients with synchronous metastatic primary colorectal cancer who received chemotherapy with bevacizumab as their initial treatment. The incidence of subsequent use of surgery and surgical outcomes were recorded. Patients were also assessed for overall survival. RESULTS: Patients who received bevacizumab-containing chemotherapy for synchronous metastatic primary colorectal cancer were divided into the non-surgery and surgery groups according to the resection status of their asymptomatic primary tumor. In the non-surgery group, two patients (4.4%) underwent additional surgery, while three patients (5.7%) required surgery for rectovesical fistula in the surgery group. The median overall survival was 17 months for the non-surgery group (95% CI: 10.6-23.3 months) and 23 months for the surgery group (95% CI: 21.3-24.6 months; P = 0.322). CONCLUSIONS: This study utilizing chemotherapy with bevacizumab did not result in an increased rate of morbidity related to the unresected primary tumor. Survival is not compromised by leaving the primary colon tumor intact.

Efficacy of sunitinib in Turkish patients with gastrointestinal stromal tumors; retrospective multicenter experience.

BACKGROUND/AIMS: Sunitinib is a multi-targeted thyrosine kinase receptor inhibitor used in patients with advanced gastrointestinal stromal tumours (GISTs). We evaluated the efficacy and tolerability of sunitinib therapy in Turkish patients with GISTs. METHODOLOGY: Between January 2001 and April 2012, 57 patients who had progressive disease or experienced unacceptable toxicity during imatinib treatment from multiple centers were investigated retrospectively. RESULTS: Thirty-three patients were male and 24 were female. The median age was 55 years (range; 16-84 years). Thirty-eight of the patients received imatinib for longer than 12 months, 13 patients received for 6-12 months, and 6 patients received for less than six months. The clinical benefit of sunitinib was 73.7%. Treatment-related adverse events were reported in 78% of the patients. Adverse events were generally mild to moderate in intensity. The median progression free survival (PFS) and overall survival (OS) of the patients that received sunitinib were 10.8 months and 23.9 months, respectively. The time of imatinib usage and response to sunitinib were independent prognostic factors for PFS and OS. Also, tumor size was an independent prognostic factor for PFS. CONCLUSIONS: Sunitinib is an effective treatment in Turkish patients with GISTs, with a clinical benefit of 73.7% and shows an acceptable tolerability.

Prognostic factors in gastrointestinal stromal tumors: multicenter experience of 333 cases from Turkey.

BACKGROUND/AIMS: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal tract. In an attempt to survey the approximate incidence, clinicopathological characteristics, and immunophenotypic features of GISTs in Turkey, we conducted a clinicopathological and immunohistochemical analysis of GISTs. METHODOLOGY: Three hundred and thirty-three patients with GIST from nine institutions in Turkey were retrospectively evaluated. RESULTS: Between January 2001 and March 2011, a total of 333 patients with GISTs were included; of these, 204 (61.2%) were male and 129 (38.8%) were female. The median age was 55 years (range; 22-102 years). At the median follow-up of 26 months (range; 4-166 months), the 1-, 3- and 5-year OS rates of the 333 patients were 96.9%, 85.8% and 78.5%, respectively. The 5-year DFS rate was 40%. The 5-year OS rate and median OS time for the patients with R0 resection were significantly higher than for patients with metastatic diseases (79.7 vs. 75.7% and not reached vs. 115 months, respectively, p=0.04). CONCLUSION: Although our results should be confirmed by prospective studies, we believe that they contribute to the literature because the study included both resectable and metastatic or unresectable GIST patients and multicenter findings from Turkey.