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1.
BackgroundThe American Joint Committee on Cancer 8th edition staging guidelines for testicular cancer established a 3 cm cutoff to subclassify stage T1 seminomas (<3 cm = pT1a and ≥3 cm = pT1b). The efficacy of this cutoff in predicting metastatic disease and impact on treatment patterns have not been studied.MethodsWe retrospectively reviewed patients with pT1 testicular seminoma in the National Cancer Database from 2004 to 2016. Receiver operating curves were used to determine the efficacy of the 3 cm tumor cutoff in identifying metastatic disease, and multivariable regression was used to compute the effect of tumor size on the rate of adjuvant therapy among Stage I patients.ResultsA total of 10,134 patients with pT1 seminoma were evaluated. The current size cutoff of 3 cm for subclassification did not exhibit high discrimination in identifying metastatic disease (area under receiver operating curve: 0.546). Surveillance has grown as the preferred treatment after orchiectomy ?32.1% in 2004 to 81.2% in 2015. However, the rate of adjuvant therapy for pT1, Stage I seminomas associated positively with tumor size even with adjustment for year of diagnosis. For tumors above 3 cm, the odds ratio stabilized around 1.9. By using the 3 cm cutoff to guide adjuvant therapy, up to 85% of T1b patients may be overtreated.ConclusionThe 3 cm cutoff for subclassification of Stage I seminoma does not predict metastatic recurrence but is associated with increased receipt of adjuvant therapy. A 3 cm cutoff and the pT1a/b classification may therefore contribute to overtreatment in many young patients with a long life expectancy for whom minimizing adverse effects should be prioritized.  相似文献   
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Phosphorylation of pp60c-src by p34cdc2 at three amino-proximal serine/threonine residues is temporally correlated with, but insufficient for, mitotic activation of c-Src kinase. The direct cause of activation during mitosis appears to be temporally correlated partial dephosphorylation of Tyr-527, a residue whose phosphorylation strongly suppresses pp60c-src activity. Site-directed mutagenesis of the serine/threonine phosphorylation sites blocks half the mitosis-specific decrease in Tyr-527 phosphorylation and half the increase in pp60c-src kinase activity. We conclude that p34cdc2 partially activates pp60c-src by a two-step process in which its serine/threonine phosphorylations either sensitize pp60c-src to a Tyr-527 phosphatase or desensitize it to a Tyr-527 kinase. Furthermore, additional events, independent of these p34cdc2-mediated phosphorylations, participate in mitotic activation of pp60c-src.  相似文献   
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Metabolic Brain Disease - Human diseases have always been a significant turf of concern since the origin of mankind. It is cardinal to know the cause, treatment, and cure for every disease...  相似文献   
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Pediatric primary “small round blue cell” tumors in the CNS represent several entities, some more common than others. Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) is rare and must be distinguished from other tumors such as medulloblastoma [1, 2], atypical rhabdoid/teratoid tumor, ependymomal tumors, metastatic sarcomas, hematologic malignancies, and other mimics. Although therapy for ES/pPNET is effective, it brings severe side effects, including cardiac toxicity, making correct recognition important [3]. As small blue cell tumors look similar, diagnosis often depends on special stains, immunohistochemistry, and molecular techniques. While the combination of membranous immunohistochemical reactivity for CD99 with cytoplasmic glycogen provides effective screening, demonstration of characteristic translocations of EWSR1 (chromosome 22) or FUS (chromosome 16) by fluorescent in situ hybridization (FISH) can confirm the diagnosis. We are reporting three primary ES/pPNET of the CNS, two of which occurred in children. While the adult case demonstrates the classic histopathology, the two pediatric cases have histopathology that significantly deviates from the usual. One is suggestive of a primary sarcoma, and the other mimics an ependymoma, but all three cases are confirmed with FISH. These observations suggest that primary ES in the CNS may have histology different from the classic morphology and a high index of suspicion should be maintained in order to make the correct diagnosis. A search of the literature suggests that these tumors are most frequently seen in children and young adults. Imaging often shows a supratentorial enhancing mass that touches the leptomeninges. Survival over three years is good but long term prognosis is unknown [3, 4].  相似文献   
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Objectives: Angioimmunoblastic T-cell lymphoma (AITL) is an aggressive peripheral T-cell lymphoma with mutations in genes encoding isocitrate dehydrogenase1 and 2 (IDH1 and IDH2). Mutant IDH generates the oncometabolite D-2-hydroxyglutarate (D-2HG). We report the first case of discordant intracellular and plasma D-2HG levels in a patient with IDH2 R172S mutated AITL. Methods: An 87-year-old woman was diagnosed with AITL in the groin lymph node by morphologic and immunophenotypic analyses, and molecular studies by DNA sequencing. D-2HG was measured in both tumoral tissue and in pre-treatment plasma by liquid chromatography-tandem mass spectrometry. Results: While D-2HG was markedly elevated in the tissue sample, its level in plasma was normal. We discuss this discordant D-2HG result within the context of previously reported discordant 2HG results in other IDH mutated tumors, and its implication for using circulating D-2HG as a biomarker of IDH mutation. In addition, this case also harbored mutations in RHOA, TET2, and TP53. The molecular pathogenesis is briefly discussed. Conclusion: While our case suggests that circulating D-2HG is not a reliable marker of IDH mutation in AITL, more cases need to be studied to arrive at a definite conclusion.  相似文献   
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Purpose: To evaluate the efficacy of a dual purpose (diagnostic and surgical) acrylic resin stent with gutta percha marker used in conjunction with 3D imaging in determination of the position and inclination of dental implants. Materials and Methods: This study was performed as a case control study. A total of 41 implants, of which 20 had been placed without the use of stents and 3D imaging (control group) and 21 were placed using stents and 3D imaging (study group), were studied. A diagnostic and surgical stent with radio‐opaque indicator (gutta percha) was fabricated to determine the planned prosthetic position and inclination of the implant. Computed tomography images were obtained and were analyzed using Denta Scan software. The position of the implant was analyzed in mesiodistal and buccolingual dimensions in terms of both position and angulation. SPSS v15.0 was used for statistical analysis (p < 0.05 was considered statistically significant). Results: The study group demonstrated an overall 98.9% efficacy of the test technique being used in the study. On qualitative assessment, the results obtained were within the defined ideal threshold level for four of five parameters (distance from buccal and lingual cortical plate, inter‐implant distance, and buccolingual angulation of the implant relative to underlying alveolar bone). For mesiodistal distance from adjacent teeth, the observation was not above threshold value for only one case. For the control group, the overall efficacy was 66.9%. Conclusion: The technique of combined use of a prosthodontic stent and 3D imaging is an efficacious and better technique in achieving an ideal position of dental implants as compared to conventional techniques using periapical and panoramic radiographs and a cast.  相似文献   
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Background

Retrospective studies demonstrated that cell cycle–related and proliferation biomarkers add information to standard pathologic tumor features after radical cystectomy (RC). There are no prospective studies validating the clinical utility of markers in bladder cancer.

Objective

To prospectively determine whether a panel of biomarkers could identify patients with urothelial carcinoma of the bladder (UCB) who were likely to experience disease recurrence or mortality.

Design, setting, and participants

Between January 2007 and January 2012, every patient with high-grade bladder cancer, including 216 patients treated with RC and lymphadenectomy, underwent immunohistochemical staining for tumor protein p53 (Tp53); cyclin-dependent kinase inhibitor 1A (p21, Cip1) (CDKN1A); cyclin-dependent kinase inhibitor 1B (p27, Kip1); antigen identified by monoclonal antibody Ki-67 (MKI67); and cyclin E1.

Intervention

Every patient underwent RC and lymphadenectomy, and marker staining.

Outcome measurements and statistical analysis

Cox regression analyses tested the ability of the number of altered biomarkers to predict recurrence or cancer-specific mortality (CSM).

Results and limitations

Pathologic stage among the study population was pT0 (5%), pT1 (35%), pT2 (19%), pT3 (29%), and pT4 (13%); lymphovascular invasion (LVI) was seen in 34%. The median number of removed lymph nodes was 23, and 60 patients had lymph node involvement (LNI). Median follow-up was 20 mo. Expression of p53, p21, p27, cyclin E1, and Ki-67 were altered in 54%, 26%, 46%, 15%, and 75% patients, respectively. In univariable analyses, pT stage, LNI, LVI, perioperative chemotherapy (CTx), margin status, and number of altered biomarkers predicted disease recurrence. In a multivariable model adjusting for pathologic stage, margins, LNI, and adjuvant CTx, only LVI and number of altered biomarkers were independent predictors of recurrence and CSM. The concordance index of a baseline model predicting CSM (including pathologic stage, margins, LVI, LNI, and adjuvant CTx) was 80% and improved to 83% with addition of the number of altered markers.

Conclusions

Molecular markers improve the prediction of recurrence and CSM after RC. They may identify patients who might benefit from additional treatments and closer surveillance after cystectomy.  相似文献   
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