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Background

T1 gastric cancer can be diagnosed only by endoscopy and is almost curable by local treatment. It has been unclear how a multidetector-row computed tomography (CT) evaluation is valuable for clinical T1 patients.

Methods

Patients with clinical T1 disease, as diagnosed by endoscopy and treated with endoscopic submucosal dissection (ESD) or surgery between October 2000 and October 2007, were examined. The efficacy of CT was evaluated by the reversal rate of endoscopic T1 by CT, the incidence of clinical M1 disease, and the accuracy of diagnosing pathological N+ disease in patients who received surgery. To confirm metachronous distant and nodal metastases, the disease-free survival (DFS) also was evaluated.

Results

A total of 761 patients, 236 treated by ESD and 525 treated with surgery, were examined. None of the patients had an endoscopic diagnosis of clinical T1 reversed by CT. No clinical M1 disease was found. Among the 525 patients who underwent surgery, 8 showed clinical N+ disease (1.5 %), while 47 demonstrated pathological N+ disease (8.9 %). The accuracy, sensitivity, specificity, positive predictive value, and negative predictive values were 90.3, 4.3, 98.7, 25, and 91.3 %, respectively. The 5-year DFS rate was 93.6 % (95 % confidence interval 91.4–95.8 %).

Conclusions

The present study suggests that diagnostic value of CT is limited for staging of clinical T1 gastric cancer patients, because the reversal rate of endoscopic T1 by CT was very low, clinical M1 disease was rare, the diagnosis of N+ status was unreliable, and metachronous M1 and N+ findings were rare.  相似文献   
34.

Background

The presence of fluid–fluid levels (FFLs) on osteosarcoma magnetic resonance imaging (MRI) is underestimated as a nonspecific finding; however, we hypothesized that FFL in conventional osteosarcoma may be indicative of chemoresistance.

Methods

In 567 stage IIB osteosarcoma patients, we evaluated the following: the incidence of FFL and their correlation with other clinicopathological variables; tumor volume change after chemotherapy and survival according to the presence of FFL; and the relationship between survival and the extent of FFL.

Results

One hundred eight (19 %) tumors showed FFL on initial MRI. FFL were correlated with proximal humeral location (P = 0.017), osteolytic on plain radiographs (P < 0.001), tumor enlargement after chemotherapy (P < 0.001), and poor histological response (P = 0.005). Large tumor (P < 0.01), proximal tumor location (P = 0.01), and presence of FFL (P < 0.01) were independent predictors of poor survival. Compared to the extensive FFL (more than one third of the tumor), small foci of FFL (less than one third of the tumor) showed a high tendency for tumor enlargement after chemotherapy (P < 0.001), poor histologic response (P = 0.001), and worse survival (P < 0.001).

Conclusions

FFL on initial MRI could predict tumor progression after chemotherapy. Notably, tumors with small foci of FFL (less than one third of the tumor) have a high propensity for poor outcome. Patients with this finding should be considered for risk-adapted therapy.  相似文献   
35.
The aim of the present study was to explore the unfavorable subset of patients with Stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0). Recurrence-free survival rates were examined in 52 patients with stage T1N2-3M0 and stage T3N0M0 gastric cancer between January 2000 and March 2010. Univariate and multivariate analyses were performed to identify risk factors using a Cox proportional hazards model. The recurrence-free survival (RFS) rates of the patients with stages T1N2, T1N3, and T3N0 cancer were 80.0, 76.4, and 100% at 5 years, respectively. The only significant prognostic factor for the survival rates of the patients with stage pT1N2-3 cancer measured by univariate and multivariate analyses was pathological tumor diameter. The 5-year RFS rates of the patients with stage pT1N2-3 cancer were 60.0%, when the tumor diameters measured <30 mm, and 88.9% when the tumor diameters measured >30 mm (P = 0.0248). These data may suggest that pathological tumor diameter is associated with poor survival in patients with small T1N2-3 tumors. Because our study was a retrospective single-center study with a small sample size, a prospective multicenter study is necessary to confirm whether small tumors are risk factor for the RFS in T1N2-3 disease.Key words: Gastric cancer, Stage II, Adjuvant chemotherapyEvery year, more than 934,000 people develop gastric cancer worldwide. After lung cancer, gastric cancer is the second most frequent cancer-related cause of death.1 Complete resection is essential to cure gastric cancer. Patients with stage II or stage III gastric cancer often develop tumor recurrence, even after complete curative resections.In 2007, the Adjuvant Chemotherapy Trial of S-1 for Gastric Cancer (ACTS-GC) phase III trial demonstrated that S-1 is effective as adjuvant chemotherapy in Japanese patients who have undergone curative D2 gastrectomy for advanced gastric cancer.2 In general, patients eligible for ACTS-GC were those diagnosed with pathological stages II and III. However, patients classified with pathological (p) stages T1N2M0, T1N3M0, and T3N0M0—which are classified as part of stage II—were excluded from the ACTS-GC trial. Because in the prior phase III studies comparing surgery alone and adjuvant chemotherapy, patients with stages T1N+ and T2-3/N0 cancer had excellent prognoses with 5-year overall survival (OS) rates of more than 80% from surgery alone,3,4 these patients were excluded from receiving adjuvant chemotherapy. Japanese Gastric Cancer Association (JGCA) guidelines clearly state that the standard treatment for these patients is surgery alone.5Therefore, patients with stage II gastric cancer have been divided into two groups: one for whom the standard treatment is surgery alone, and the other for whom the standard treatment is surgery and adjuvant chemotherapy with S-1. Before the advent of ACTS-GC, survival rates were poorer in the latter group than in the former. However, treatment with adjuvant chemotherapy with S-1 has reversed this trend. Now, patients in the latter group receiving S-1 adjuvant chemotherapy have 5-year OS rates of 84.2%.6 Therefore, it may be old rationale that dictates that patients in the former group should be excluded from receiving adjuvant chemotherapy, because the 5-year OS rates are now more than 80% by S-1 adjuvant chemotherapy in the latter group. Five-year OS rates of 80% would not be obtained by surgery alone. Among those patients with stage II gastric cancer assigned to the surgery alone group, some may have a poor prognosis and be good candidates for adjuvant chemotherapy. The aim of the present study was to explore the unfavorable subset of patients among those with stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0).  相似文献   
36.
37.

Objective

Autism spectrum disorders (ASDs) are a group of early childhood-onset neurodevelopmental disorders characterized by deficits in social interaction and language skills, and repetitive behaviors. Brain-derived neurotrophic factor (BDNF) plays a critical role in the differentiation of normal neuronal cells during embryonic and postnatal neuronal development through its neurotrophic effects.

Methods

In this study, we performed a family-based association test (FBAT) between single nucleotide polymorphisms (SNPs; rs6265, rs11030101, rs7103411, and rs7103873) or haplotypes in the BDNF gene and affection status or several quantitative traits characterized by ADI-R with151 Korean trios, including a child diagnosed as ASDs.

Results

While no significant association was found between SNPs or haplotypes and the ASDs disease status, a quantitative transmission disequilibrium test (QTDT) by using quantitative traits identified associations of the SNPs (rs6265 and rs11030101) with a domain score for "Restricted, Repetitive and Stereotyped patterns of behavior" (C domain), especially at the subdomain scores for "encompassing preoccupation or circumscribed pattern of interest" (C1) (rs6265A allele, dominant model, p-value=0.019; rs11030101 A allele, additive model, p-value=0.015) and "preoccupations with part of objects or non-functional elements of material" (C4) (rs11030101 A allele, additive model, p-value=0.015) within the ADI-R diagnostic algorithm. In addition, significant associations were also identified between the haplotypes and these quantitative traits (C1, p-value=0.016; C4, p-value=0.012).

Conclusion

We conclude that BDNF gene polymorphisms have a possible role in the pathogenesis of ASDs.  相似文献   
38.
Seven-band grouper, Epinephelus septemfasciatus, is of considerable economic value and a candidate species of aquaculture in Eastern Asia. It is necessary to monitor the stocks for the sustainable use and aquaculture of the species. Monitoring genetic variation among marine resources necessitates the development of genetic markers. Here, we report 22 polymorphic microsatellite markers with 2–16 alleles per locus. The mean observed and expected heterozygosity per locus was 0.53 and 0.57, respectively. Cross-amplification revealed variability in Epinephelus bruneus and Epinephelus akaara. The 22 markers developed can be a valuable tool for genetic conservation of this species.  相似文献   
39.
40.
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the efficacy of intravitreal aflibercept monotherapy for submacular hemorrhage secondary to neovascular age-related...  相似文献   
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