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AIM: Sunitinib has shown benefit in patients with imatinib (IM)–resistant gastrointestinal stromal tumor (GIST). However, its advantages are somewhat diminished because of associated toxicities. Herein, we clarify the efficacy and safety of fractioned dose regimen of sunitinib by a pharmacokinetic and efficacy study. MATERIALS AND METHODS: Between 2001 and March 2013, a total of 214 patients with metastatic GIST was treated at Chang Gung Memorial Hospital. Among them, 55 (11.6%) patients who received sunitinib were investigated. One group of patients was administered with standard dose of once-daily sunitinib (standard dose group) and the other group was administered with standard total daily dose of sunitinib in fractioned doses (fractioned dose group). RESULTS: Thirty-two male and 23 female patients with a median age of 55 years received sunitinib. The median duration of sunitinib administration was 9.2 months. The clinical benefit was 65.2%. The mean peak blood level of sunitinib in patients with fractioned doses was significantly lower than that in those with once-daily dose (83.4 vs 50.1 ng/ml, P = .01). The rates of adverse effects of hand-foot syndrome, mucositis, and yellow skin were significantly decreased by fractioned doses of sunitinib. However, the progression-free and overall survival did not differ between patients with different treatment regimens. CONCLUSION: The fractioned dose regimen of sunitinib appears to be a safe and effective treatment for patients with IM-resistant/intolerant GISTs. Significantly decreased toxicity of this regimen could be explained by significantly lower peak sunitinib blood level. However, the treatment efficacy is not reduced by this regimen.

Background For selected patients with metastatic gastrointestinal stromal tumor (GIST) who have received first-line imatinib (IM) and are undergoing cytoreductive surgery, response to IM at time of surgery correlates with resection completeness as well as favorable progression-free survival (PFS) and overall survival (OS). However, surgical impact in GIST patients receiving second-line sunitinib (SU) is still not well clarified. Materials and methods Between 2001 and 2014, 86 of 311 metastatic GIST patients received SU. Among them, 69 patients eventually experienced progression. Twenty-six patients who experienced local progression (LP) and underwent surgeries were investigated. Each tumor was assessed for genetic alterations before and after surgery. Results Twenty-six GIST patients receiving SU who experienced LP underwent surgery after a median of 6.2 months of SU use. Nineteen patients (73.1%) had undergone prior surgery on IM. The complication rate was 15.3%, and no additional operation was required for GIST patients receiving SU and experiencing LP who underwent surgery. The median PFS and OS times after surgery and start of SU were 5.2 and 18.9 months, respectively, and 16.4 and 26.0 months, respectively (median follow-up of 15.2 months). GIST patients receiving SU with LP (N = 26) may gain a significant PFS and OS benefit with surgery when compared with those not undergoing surgery (N = 43) (p = 0.003 and p = 0.02, respectively). Secondary exon 17 mutation occurred commonly and might explain SU resistance (8/23; 34.8%). Conclusion Surgery is feasible in highly selected patients with metastatic GIST who are receiving SU and experiencing LP. Those patients may also have significantly prolonged PFS and OS after surgery. Secondary exon 17 mutation might explain SU resistance.

Purpose Imatinib mesylate (IM) demonstrates substantial efficacy in most patients with metastatic gastrointestinal stromal tumors (GISTs). However, progression of GIST eventually develops and emerges as a challenge. To assess the role of surgery in the multidisciplinary management of GISTs, we studied the surgical outcomes in GIST patients receiving IM. Materials and Methods Between 2001 and May 2009, 161 metastatic GIST patients received IM. Among them, 35 patients undergoing 38 surgeries were investigated. Patients were categorized based on extent of disease before surgery (responsive or stable disease (PR, SD), local progression (LP), and generalized progression (GP)). Each tumor was investigated for genetic alteration before and after surgery. Results Disease status before surgery was significantly associated with surgical result. Gross tumor clearance was achieved in 42.9% of patients with responsive disease, but only 4.8% of those with focal resistance and 0% of those with disease progression (P = 0.022). GIST patients with PR, SD, and LP had significant better 2-year progression-free survival and overall survival than those with GP. Secondary mutations tended to be found more frequently in GIST patients with LP after surgery than those with response (10/21 (47.6%) vs. 2/14 (14.3%); P = 0.07), indicating that surgery may prevent potential development of secondary mutation in GIST patients with response. Secondary kit mutations were also found more frequently with primary exon 11 mutation than those with exon 9 mutation (38.7% vs. 16.7%; P = 0.394). Conclusions Surgery may benefit selected GIST patients with PR, SD, and LP, especially for patients with LP because patients with LP had comparable survival to that of patients with responsive lesion. Surgery may prevent potential development of secondary mutations in selected patients with response after IM treatment. Secondary kit mutation was found more frequently in GIST patients with a primary kit exon 11 mutation than those with a primary kit exon 9 mutation. J. Surg. Oncol. 2010;102:599–603. © 2010 Wiley-Liss, Inc.

Purpose Cholangiocarcinoma (CCA) is a lethal malignancy that afflicts thousands of patients worldwide. Stratifin has been shown to participate in mediating G2 arrest in several cancers, and cells that express stratifin could contribute to the chemo- and radioresistance of cancers and poor prognosis. However, the clinical impact of stratifin on clinicopathological features of mass forming (MF)-CCA is still unclear. Methods Seventy-eight patients with MF-CCA who had undergone hepatectomy were selected for an immunohistochemical study of stratifin. Sixteen clinicopathological variables were used for the survival analyses. Results Seventy-eight MF-CCA patients (36 men and 42 women) were studied. Cytoplasmic immunostaining with membrane prominence was found in 52.6% (41/78) of patients with MF-CCA after hepatectomy; this was significantly associated with elevated carcinoembryonic antigen (CEA) levels. During the median follow-up duration of 13.6 months, the 5-year overall survival (OS) rate was 14.9%. Univariate analysis showed that an absence of clinical symptoms, better nutritional status, lower alkaline phosphatase, smaller tumor, negative lymph node metastasis, negative stratifin staining, and curative hepatic resection were associated with favorable OS rate for MF-CCA patients after hepatectomy. Multivariate Cox proportional hazard analysis showed that the absence of clinical symptoms, negative lymph node metastasis, and curative hepatectomy independently predicted MF-CCA patients with favorable OS rate after hepatectomy. Conclusions Overexpression of stratifin was significantly associated with elevated CEA levels in patients with MF-CCA. The favorable OS for MF-CCA patients depends on the absence of clinical symptoms, negative lymph node metastasis, and curative hepatectomy. J. Surg. Oncol. 2010;102:608–614. © 2010 Wiley-Liss, Inc.

We investigated whether the intensity of thymidylate synthase (TS) staining in tissue samples obtained from gastric cancer (GC) patients undergoing gastrectomy could predict response to 5-FU-based adjuvant chemotherapy after gastrectomy.Clinicopathological features of 124 patients with histologically proven GC who underwent radical gastrectomy were retrospectively reviewed. Tissue samples obtained from these patients were immunohistochemically stained for assessing TS expression. We arbitrarily classified the TS staining results as low (20% cytoplasmic immunostaining) and high (or =20% cytoplasmic immunostaining) TS expression.The clinicopathological features of the low TS expression group patients were typically similar to those of the high TS expression group patients. However, multivariate forward stepwise logistic regression analysis revealed that low TS expression was independently associated with females and responders to 5-FU-based adjuvant chemotherapy. The median follow-up duration for the 124 GC patients who had undergone curative resection was 41.3 months. The GC patients who showed poor tumor differentiation and high TS expression had short disease-free survival (DFS) and overall survival (OS).Low TS expression is significantly associated with female GC patients and responders to 5-FU-based adjuvant chemotherapy. It predicts longer DFS and OS in selected GC patients treated with 5-FU-based adjuvant chemotherapy after curative resection. The results suggest that prospective assessment of TS staining intensity in tissue samples obtained from GC patients undergoing gastrectomy would be useful to predict the patients who would be benefited from 5-FU-based adjuvant chemotherapy after gastrectomy.

Dielectric resonator-loaded circular microstrip patch antennas can be used as an alternative way to generate circular polarization. The dielectric resonator is placed on the edge of the circular microstrip patch antenna to result both strong coupling effect and two degenerated orthogonal modes. Then, we choose the feeding point, the placed position and size of DR, and the height of antenna as key tuning parameters; both wide circular polarization and impedance matching are achieved. Application is given for WLAN 2.4 GHz band. Both simulated and measured data are matched well. Measured results show that the center frequency is at 2.45 GHz. The impedance bandwidth is 19.2%. Besides, the axial ratio bandwidth is 3.7% (2.39–2.48 GHz). The radiation patterns are broadside radiations and high antenna gain of 8.6 dBic is achieved. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1470–1473, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24373

Most gastrointestinal stromal tumors (GISTs) express constitutively activated mutation of kit or platelet-derived growth factor receptor alpha (PDGFRA), which are therapeutic targets for imatinib. Results of 64 Taiwanese with advanced GIST treated with imatinib were reported.Between 2001 and May 2006, a prospective, non-randomized, and a single center trial containing 64 Taiwanese patients with advanced GIST treated with imatinib was conducted. Each tumor was investigated for mutations of kit or PDGFRA.The median follow-up time after imatinib administration was 16.1 months. 12 patients (18.8%) had complete response (CR), 24 (37.5%) had a partial response (PR), 12 stationary disease (18.8%), 16 progressive disease (25.0%). The 64 Taiwanese with advanced GIST had an estimated median survival of 48.0 months and 4-year survival rate for 76.1%. Kit mutation was found in 49 of 54 (90.7%) test patients and five of them had no mutation (9.3%). No PDGFRA mutant was identified. In 40 patients harboring kit exon 11 mutations, the CR and PR rates (ORR) were 57.5% , nine patients with tumors containing kit exon 9 mutation had ORR rates of 22.2%, and five patients with no mutation had ORR rates of 60.0% (not significant; P = 0.149).Activated mutation of kit constituted 90.7% genetic alteration of Taiwanese with advanced GIST and no PDGFRA mutation was detected. Imatinib induced a sustained objective response in more than half of Taiwan advanced GIST patients. ORR did not differ between patients whose GISTs had no mutation, kit exon 9, and 11 mutations.

A four-pole quasi-elliptic function bandpass filter for a compact low-temperature cofired ceramic is proposed in this paper. The filter is constructed by the open-loop resonators and the miniaturized hairpin resonators that can be coupled through the apertures on the common ground plane, and the 0/spl deg/ feed structure adds two extra transmission zeros to the filter response. It is shown that the filter occupies a very small size. As a result, the proposed structure of the filter occupies a very small circuit area and has a good out-of band rejection.

Sunitinib, a multitargeted receptor Y kinase inhibitor (TKI) used for the treatment of renal cell carcinoma and gastrointestinal stromal tumor (GIST), is notorious for cutaneous adverse effects, such as hand-foot skin reaction (HFSR). To explore the underlying mechanism of HFSR, we enrolled 53 sunitinib-treated GIST patients, including 23 HFSR cases, and 30 tolerant controls. Among the 29 biomarkers examined, soluble FasL (sFasL) showed significant increase in the plasma, blister fluids, and skin lesions of HFSR patients. The plasma levels of sFasL were significantly correlated with those of sunitinib in HFSR patients. In addition to FasL, augmented expression of Fas and active caspase 3 was also detected in the epidermis of HFSR patients. The increased FasL caused keratinocyte death, as the use of anti-FasL antibody specifically blocked cell apoptosis. Oral administration of sunitinib to mice increased skin susceptibility to mechanical injuries in a dose/time-dependent manner. The administration of sunitinib (40 mg kg(-1) per day) for 4 weeks to mice caused the maximally affected skin area with an erosion-to-ulceration response to tape-stripping. The skin biopsies of mice administered sunitinib exhibited increased expression of Fas and FasL in the apoptotic keratinocytes in the epidermis. Our data revealed that Fas/FasL interaction mediates keratinocyte death in sunitinib-induced HFSR.

To establish a real-time, web-based, customized audiometry database system, we worked in cooperation with the departments of medical records, information technology, and otorhinolaryngology at our hospital. This system includes an audiometry data entry system, retrieval and display system, patient information incorporation system, audiometry data transmission program, and audiometry data integration. Compared with commercial audiometry systems and traditional hand-drawn audiometry data, this web-based system saves time and money and is convenient for statistics research.

In this study, we investigated the prognostic significance of the number of examined lymph nodes in node-negative gastric adenocarcinoma (GC).A total of 1194 node-positive and 1030 node-negative GC patients undergoing potentially curative gastrectomy was enrolled in this study. Patients were stratified into 3 groups according to the number of examined lymph nodes: group 1, ≤ 15; group 2, 16-25; group 3,25.Patients with node-negative GC had significantly favorable survival compared with those with node-positive. Among patients with node-negative T2-T4 disease, the percentage of locoregional relapse was higher in those with25 examined lymph nodes than in those with ≥ 25 examined lymph nodes. The number of examined lymph nodes affected the overall survival rates for patients with node-negative T2-T4 GC but not for patients with T1 lesions. Tumor size, tumor location, the number of examined lymph nodes, T status, and the presence of perineural invasion were significant prognostic factors as determined by multivariate analysis in node-negative GC.No survival benefit of examining ≥ 15 lymph nodes was noted for patients with node-negative T1 GC. Extensive lymphadenectomy in patients with node-negative T2-T4 lesions in whom the number of examined lymph nodes was25 had favorable survival.

PURPOSE: Our preliminary report of imatinib mesylate (IM) in gastrointestinal stromal tumor (GIST) patients detailed a high response rate; however, the long-term result is still unknown. We conducted an analysis of Taiwan advanced inoperable/metastatic GIST patients treated on IM regarding survival, pattern of failure, potential prognostic factors, and mutational status. PATIENTS AND METHODS: From 2001 to 2010, patients with pathologically proven advanced inoperable/metastatic GIST receiving IM were enrolled onto this study. Data on KIT mutational status, measurable tumor size, and other potential prognostic factors were prospectively collected. Patients were followed up for a median of 33.6 months. RESULTS: There were 171 patients (106 men and 65 women) with response rate, and their clinical benefit for IM was 57.3% and 87.1%, respectively. Median progression-free survival (PFS) and overall survival (OS) for these 171 patients are 37.6 and 71.0 months, respectively. Of 171 patients, 120 (70.2%) remained on long-term IM use. Poor performance status, tumor larger than 11.5 cm, primary resistance, and the presence of an exon 9 mutation were independently associated with unfavorable PFS. Regarding OS, poor performance status, primary resistance, and tumor larger than 11.5 cm were three independently unfavorable predictors. CONCLUSIONS: The median PFS and OS of 171 GIST patients are 37.6 and 71.0 months, respectively. Poor performance status, tumor size larger than 11.5 cm, primary resistance, and an exon 9 mutation were independently associated with unfavorable PFS. Regarding OS, poor performance status, primary resistance, and tumor size larger than 11.5 cm were three independent unfavorable predictors.

Overweight/obesity is currently a common health issue that may cause many diseases, even malignancies. The influence of steatosis on long-term results of surgical treatment for hepatocellular carcinoma (HCC) is not well known. The aim of this study is to analyze the results of hepatectomy for HCC patients with steatosis.The study included 1048 patients who underwent hepatectomy for HCC from 1999 to 2005. The patients were divided into two groups; group A patients without steatosis (n = 693) and group B patients with steatosis (n = 355). The clinicopathological data and long-term survival were analyzed.Mean tumor size in group B patients was smaller than that in group A patients (4.61 ± 3.40 vs. 5.91 ± 4.36 cm, p0.01). Group B patients showed lower tumor differentiation grade, lower vascular invasion rate and better 5-year overall survival compared to group A patients (61.2% vs. 50.1%, p = 0.001). By multivariate analysis, steatosis was found to be associated with well-differentiated, small-sized, and less α-fetoprotein productive tumors. When focusing on the tumors5 cm in diameter, group B patients had better survival rate than group A patients (p = 0.041). Vascular invasion and steatosis were independent prognostic factors for the overall survival.HCC in steatotic liver was less aggressive than that in non-steatotic liver. HCC patients with steatosis have better surgical outcomes than those without steatosis. Vascular invasion and steatosis were independent prognostic factors for the overall survival if tumors were5 cm in diameter.

Background Hepatocellular carcinoma (HCC) is the fifth most common malignancy in the world and constitutes the leading cause of cancer-related death among men, and second among women in Taiwan. Liver cirrhosis and HCC are relatively prevalent, and 80% to 85% of the patients with these conditions have positive results for hepatitis B surface antigen in Taiwan. Only 5% of the general population is seronegative for all hepatititis B virus (HBV) markers. This is the first study to determine the role of ezrin upon HBV HCC cell and patients with HBV HCC undergoing hepatectomy Methods Immunohistochemical study with ezrin in 104 human HBV-HCC cases were carried out to investigate its association with the clinicopathological features and the outcomes of 104 HBV-HCC patients undergoing hepatetomy. In addition, DNA constructs including the wild type ezrin (wt-ezrin) and mutant ezrin Tyr353 (Y353) were transfected into Hep3B cell to study its role in tumor invasion and differentiation. Results HBV HCC patients with ezrin over-expression independently have smaller tumor size, cirrhotic liver background, poor tumor differentiation, and more vascular invasion. Ezrin expression status has no impact on survival for HBV-HCC patients undergoing hepatectomy. The in vitro assay showed that wt-ezrin Hep3B cells have a significant higher level of AFP secretion and higher invasion ability as compared with the control and Y353- ezrin Hep3B cells. Conclusion Ezrin over-expression contributed to de-differentiation and invasion of HBV-HCC cell. HBV-HCC patients with ezrin over-expression were independently associated with tumor with smaller size, cirrhotic liver background, poor differentiation, and vascular invasion.

Backgrounds/aims Intrahepatic cholangiocarcinoma and colorectal cancer liver metastasis are the most primary and secondary adenocarcinoma of the liver, respectively. A large-scale long-term comparative study of these two cohort patient is lacking. Methods A total of 166 colorectal cancer liver metastasis patients and 206 intrahepatic cholangiocarcinoma patients who had undergone curative liver resection were retrospectively analysed. Among 206 intrahepatic cholangiocarcinoma, there were 47 intraductal growth type-intrahepatic cholangiocarcinoma and 159 non-intraductal growth type-intrahepatic cholangiocarcinoma. The demographics, clinicopathological data, immunohistochemical study and survival were analysed. Results The intrahepatic cholangiocarcinoma patients were more female-predominated, associated with hepatolithiasis, symptomatic, jaundiced, and with larger tumour size compared with those of colorectal cancer liver metastasis. Prognostic factors of intrahepatic cholangiocarcinoma were pathologic staging, histologic pattern and section margin; whereas prognostic factors of colorectal cancer liver metastasis were rectal origin, differentiation, section margin and bilobar distribution. CK7 and CK20 differentiated majority of intrahepatic cholangiocarcinoma from colorectal cancer liver metastasis, while CDX2 and MUC5AC helped to differentiate inconclusive cases. The 1-, 3-, 5- and 10-year survival rates of colorectal cancer liver metastasis were 77%, 31%, 20% and 14%, compared to 53%, 21%, 13% and 7% of intrahepatic cholangiocarcinoma (p = .0001). Furthermore, the survival of colorectal cancer liver metastasis was comparable to staged II intrahepatic cholangiocarcinoma (p = .8866) and intraductal growth type-intrahepatic cholangiocarcinoma (p = .1915). Conclusions Demographics, precipitating factor, clinical manifestations, and prognostic factors of colorectal cancer liver metastasis and intrahepatic cholangiocarcinoma differed remarkably. High incidence of CDX2 and MUC2 expression in colorectal cancer liver metastasis and intraductal growth type-intrahepatic cholangiocarcinoma might explain their similar cytoarchitecture and survival.

Cholangiocarcinoma (CCA) is a lethal disease afflicting many thousands of patients worldwide. We have previously developed an oral thioacetamide (TAA)-induced model of rat CCA that recapitulates the histologic progression of human CCA. Our objective was to evaluate the feasibility of animal PET in detecting CCA in the setting of the TAA rat model. Male Sprague–Dawley rats (n = 30) were used in this study. Drinking water with TAA 300 mg/l was administered orally in 26 rats, and animal PET was performed at 20 weeks after initiation of TAA. A total of four rats served as controls. Animal PET images were acquired sequentially using both C-11 acetate and 2-deoxy-2-[F-18]fluoro-d-glucose (FDG) to determine the optimal tracer. Dynamic animal PET images were collected to assess the optimal scan time based on the highest tumor-to-liver (T/L) ratio using time–activity curves. Animal PET findings were compared lesion by lesion with the results of autoradiography and the histological data. FDG animal PET images had a higher T/L ratio compared to images obtained with C-11 acetate as a marker. The optimal scan time for FDG animal PET was determined as 90 min postinjection of the tracer. This was when the T/L ratio reached its peak. Necropsy and histology confirmed the presence of TAA-induced CCA in 22 rats (84.6 %). Static animal PET images showed intense FDG uptake in 17 of the 22 tumor-bearing animals (77.3%). The average T/L ratio was 1.60 ± 0.09. The sensitivity and specificity of animal PET in the detection of CCA were 77% (17/22) and 100% (4/4), respectively. We conclude that animal PET in the setting of the TAA rat model seems to be feasible for the detection of CCA. Future translational studies are needed to confirm and expand our findings.

Imatinib mesylate showed a sustained objective response in patients with advanced gastrointestinal stromal tumors (GISTs) since its introduction in 2001. Here we reported genetic changes during imatinib mesylate treatment especially when the patient had partial response or stationary disease. Between 2001 and June 2005, 44 advanced GIST patients were treated with imatinib mesylate. Among them, five patients (11.9%) (four with partial response and one with stationary disease) received surgical treatment during imatinib mesylate treatment. We compared the genetic status of each tumor in the five patients before and after imatinib mesylate treatment. Symptomatic gallbladder stone with or without cholecystitis (two patients), lower GI bleeding (one patient), upper GI bleeding (one patient), and enterocutaneous fistula (one patient) comprised the indications for operation. Before imatinib mesylate treatment, four of the five patients displayed deletion mutation and one patient displayed point mutation in exon 11. After treatment, one patient developed second novel missense mutation in exon 17 with acquired resistance since he was administered with only half dose of imatinib mesylate. The other four patients taking the same dose of imatinib mesylate exhibited identical mutation to the previous lesions. Necrosis of large and bulky tumors after imatinib mesylate therapy might be the reason of gastrointestinal hemorrhage and enterocutaneous fistula requiring surgical intervention. Imatinib mesylate could induce acquired resistance during treatment and second novel mutation might be the reason.

AIM: Most gastrointestinal stromal tumors (GISTs) express constitutively activated mutant isoforms of kit kinase or platelet-derived growth factor receptor alpha (PDGFRA), which are potential therapeutic targets for imatinib mesylate (Glivec). Partial response occurred in almost two thirds of GIST patients treated with Glivec. However, complete response (CR) after Glivec therapy was sporadically reported. Here we illustrated advanced GIST patients with CR after Glivec treatment. METHODS: Between January 2001 and June 2005, 42 advanced GIST patients were treated with Glivec. Patients were administered 400 mg of Glivec in 100-mg capsules, taken orally daily with food. The response of the tumor to Glivec was evaluated after one month, three months, and every three months thereafter or whenever medical need was indicated. Each tumor of patients was investigated for mutations of kit or PDGFRA. RESULTS: The median follow-up time of the 42 ad-vanced GIST patients treated with Glivec was 16.9 months (range, 1.0 - 47.0 months). Overall, 3 patients had complete response CR (7.1 %), 26 partial response (67.8 %), 5 stationary disease (11.9 %), and 3 progressive disease (11.9 %). The median duration of Glivec administration for the three patients was 36 months (range, 23-36 months). The median time to CR after Glivec treatment was 20 months (range, 9-26 months). Deletion and insertion mutations of c-kit exon 11 and insertion mutation of c-kit exon 9 were found in two cases and one case, respectively. CONCLUSION: Complete response (CR) can be achi-eved in selected advanced GIST patients treated with Glivec. The median time to CR after Glivec treatment was 20 months. Deletion and insertion mutations of kit exon 11 and insertion mutation of kit exon 9 contribute to the genetic features in these selected cases.

A miniature antenna for AGPS is presented. Its size is 10 mm times 3 mm times 3 mm, and more suitable to hand-held applications. The bandwidth of AGPS chip antenna is 30 MHz, gain is about 3.4 dBi, and radiation patterns are wide beamwidth in three basic planes. Although the antenna polarization seems to be linear polarization, the receiving effect is still good for only 3 dB degradation in the gain performance

A CPW-fed rectangular dielectric resonator antenna is presented. The reflection coefficient and radiation patterns of such a dielectric resonator antenna with a high dielectric constant fed by an open-ended coplanar waveguide are studied. In the antenna design, the offset distance from the center of the dielectric resonator antenna to the open-ended slot center, can be used to tune the input impedance on the CPW-fed dielectric resonator antenna. Also, the calculated and experimental reflection coefficient, center frequency, antenna bandwidth, and radiation patterns are compared.

AIM: To report preliminary results of the efficacy and safety of sunitinib in the management of Taiwanese gastrointestinal stromal tumors (GIST) patients facing imatinib mesylate (IM) intolerance or failure. METHODS: Between 2001 and May 2010, 199 Taiwanese patients with metastatic GIST were treated at Chang Gung Memorial Hospital. Among them, 23 (11.6%) patients receiving sunitinib were investigated. RESULTS: Sixteen male and 7 female patients with a median age of 59 years (range: 24-83 years) received sunitinib. Twenty-two GIST patients changed to sunitinib because of IM failure and 1 because of intolerance. The median duration of sunitinib administration was 6.0 mo (range: 2-29 mo). The clinical benefit was 65.2% [2 complete response (CR), 4 partial response (PR), and 9 stationary disease (SD); 15/23]. In 12 patients harboring mutations of the kit gene at exon 11, the clinical benefit rate (CR, PR, and SD) was 75.0% and 6 patients with tumors containing kit exon 9 mutations had a clinical benefit of 50.0% (not significant, P = 0.344). The progression free survival (PFS) and overall survival (OS) did not differ between patients whose GISTs had wild type, KIT exon 9, or KIT exon 11 mutations. Hand-foot syndrome was the most common cause of grade III adverse effect (26.1%), followed by anemia (17.4%), and neutropenia (13.0%). During the median 7.5-mo follow-up after sunitinib use, the median PFS and OS of these 23 GIST patients after sunitinib treatment were 8.4 and 14.1 mo, respectively. CONCLUSION: Sunitinib appears to be an effective treatment for Taiwanese with IM-resistant/intolerant GISTs and induced a sustained clinical benefit in more than 50% of Taiwanese advanced GIST patients.

To examine the impact of imatinib mesylate (Glivec) on patient survival and response and its safety, and the correlation of the response rate with the kit gene mutation status.Thirty-three of 74 (44.6%) small bowel gastrointestinal stromal tumor (GIST) patients who developed recurrence after curative resection and not treated with Glivec were classified as group A patients. Twenty-two advanced small bowel GIST patients treated with Glivec were classified as group B patients. Clinicopathological features, post-recurrence and overall survival rates were compared. Each tumor in group B patients was investigated for mutations of kit or platelet-derived growth factor alpha (PDGFRA). The mutation type was correlated with clinical outcomes. The anti-tumor effect and safety of Glivec in group B patients were also assessed.Advanced small bowel GIST patients treated with Glivec had substatntially longer post-recurrence survival and higher overall survival rates than those not treated with Glivec. A total of 15 patients had a partial response (PR) (67.8%). Activated mutations of c-kit were found in 16 of 19 tested patients and no PDGFRA mutant was identified. In 13 patients with GISTs harboring exon 11 kit mutations, the partial response rate (PR) was 69.3%, whereas two of three patients with tumors containing an exon 9 kit mutation had an overall response rate (ORR) of 66.7% (not significant).Glivec significantly prolongs the post-recurrence and overall survival of Asian patients with advanced GISTs. Glivec induces a sustained objective response in more than half of Asian patients with advanced small bowel GISTs. Activated mutations of kit exon 11 are detectable in the vast majority of GISTs. There is no difference in the PR rate for patients whose GISTs have kit exon 9 and exon 11 mutations.