Endobronchial ultrasound-guided transbronchial biopsy of peripheral pulmonary lesions: how many specimens are necessary?

Background: Although endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB) has been shown to increase the diagnostic yield over conventional bronchoscopic techniques, an important issue regarding the optimal number of biopsy specimens required has not been thoroughly investigated. Objectives: We sought to examine whether the number of biopsy specimens taken was associated with the diagnostic yield of EBUS-guided TBB and, if this was the case, to determine the optimal number of specimens required for the maximum diagnostic yield in peripheral pulmonary lesions. Methods: The medical records of patients undergoing EBUS-guided TBB for the diagnosis of peripheral pulmonary lesions from 2008 to 2010 were retrospectively reviewed. The association of clinical and radiological features, including the number of biopsy specimens, with the diagnostic yield was analysed. Results: A total of 384 patients were included for analysis. The overall diagnostic yield of EBUS-guided TBB was 73%, and the only factor influencing the diagnostic yield was the position of the probe. Patients in which the EBUS probe was placed within the lesions had a significantly higher yield (85%) than those in which the probe was adjacent to or outside the lesions (38%; p < 0.001). When the number of biopsy specimens was determined based on their adequacy, it was an insignificant factor in predicting the diagnostic yield. Conclusions: Probe position independently predicts the diagnostic yield of EBUS-guided TBB. In real-world practice, the optimal number of biopsy specimens should be decided on a case-by-case basis.     

Unidirectionally aligned line patterns driven by entropic effects on faceted surfaces

A simple, versatile approach to the directed self-assembly of block copolymers into a macroscopic array of unidirectionally aligned cylindrical microdomains on reconstructed faceted single crystal surfaces or on flexible, inexpensive polymeric replicas was discovered. High fidelity transfer of the line pattern generated from the microdomains to a master mold is also shown. A single-grained line patterns over arbitrarily large surface areas without the use of top-down techniques is demonstrated, which has an order parameter typically in excess of 0.97 and a slope error of 1.1 deg. This degree of perfection, produced in a short time period, has yet to be achieved by any other methods. The exceptional alignment arises from entropic penalties of chain packing in the facets coupled with the bending modulus of the cylindrical microdomains. This is shown, theoretically, to be the lowest energy state. The atomic crystalline ordering of the substrate is transferred, over multiple length scales, to the block copolymer microdomains, opening avenues to large-scale roll-to-roll type and nanoimprint processing of perfectly patterned surfaces and as templates and scaffolds for magnetic storage media, polarizing devices, and nanowire arrays.     

Three differentiation states risk-stratify bladder cancer into distinct subtypes

Current clinical judgment in bladder cancer (BC) relies primarily on pathological stage and grade. We investigated whether a molecular classification of tumor cell differentiation, based on a developmental biology approach, can provide additional prognostic information. Exploiting large preexisting gene-expression databases, we developed a biologically supervised computational model to predict markers that correspond with BC differentiation. To provide mechanistic insight, we assessed relative tumorigenicity and differentiation potential via xenotransplantation. We then correlated the prognostic utility of the identified markers to outcomes within gene expression and formalin-fixed paraffin-embedded (FFPE) tissue datasets. Our data indicate that BC can be subclassified into three subtypes, on the basis of their differentiation states: basal, intermediate, and differentiated, where only the most primitive tumor cell subpopulation within each subtype is capable of generating xenograft tumors and recapitulating downstream populations. We found that keratin 14 (KRT14) marks the most primitive differentiation state that precedes KRT5 and KRT20 expression. Furthermore, KRT14 expression is consistently associated with worse prognosis in both univariate and multivariate analyses. We identify here three distinct BC subtypes on the basis of their differentiation states, each harboring a unique tumor-initiating population.     

Secreted protein, acidic and rich in cysteine-like 1 (SPARCL1) is down regulated in aggressive prostate cancers and is prognostic for poor clinical outcome

Prostate cancer is the second leading cause of cancer death among United States men. However, disease aggressiveness is varied, with low-grade disease often being indolent and high-grade cancer accounting for the greatest density of deaths. Outcomes are also disparate among men with high-grade prostate cancer, with upwards of 65% having disease recurrence even after primary treatment. Identification of men at risk for recurrence and elucidation of the molecular processes that drive their disease is paramount, as these men are the most likely to benefit from multimodal therapy. We previously showed that androgen-induced expression profiles in prostate development are reactivated in aggressive prostate cancers. Herein, we report the down-regulation of one such gene, Sparcl1, a secreted protein, acidic and rich in cysteine (SPARC) family matricellular protein, during invasive phases of prostate development and regeneration. We further demonstrate a parallel process in prostate cancer, with decreased expression of SPARCL1 in high-grade/metastatic prostate cancer. Mechanistically, we demonstrate that SPARCL1 loss increases the migratory and invasive properties of prostate cancer cells through Ras homolog gene family, member C (RHOC), a known mediator of metastatic progression. By using models incorporating clinicopathologic parameters to predict prostate cancer recurrence after treatment, we show that SPARCL1 loss is a significant, independent prognostic marker of disease progression. Thus, SPARCL1 is a potent regulator of cell migration/invasion and its loss is independently associated with prostate cancer recurrence.     

Factors Affecting Colonoscope Insertion Time in Patients With or Without a Colostomy After Left-Sided Colorectal Resection

Background/Aims

We examined whether the insertion time for colonoscopies performed after left-sided resection was different in patients with a colostomy from that in patients without a colostomy and identified factors that could impact colonoscopy performance.

Methods

We included consecutive patients who underwent colonoscopy between July 2005 and March 2011 after left-sided colorectal resection for colorectal cancer. We classified surgical methods according to the presence or absence of a colostomy and evaluated colonoscope insertion time retrospectively. Furthermore, we analyzed factors that might affect insertion time.

Results

A total of 1,041 patients underwent colonoscopy after left-sided colorectal resection during the study period. The colonoscopy completion rate was 98.6?%, and the mean insertion time was 6.1?±?4.6?min (median 4.7?min, range 0.3?C35.8?min). A shorter resection length of colon, the presence of a colostomy, and a lower endoscopist case volume were found to be independent factors associated with prolonged insertion time in patients with left-sided colorectal resection. Among experienced colonoscopists, no colonoscopy-associated or clinical factors were found to affect insertion time. However, a shorter resection length of colon, the presence of a colostomy, and poor bowel preparation were associated with prolonged insertion time among inexperienced endoscopists.

Conclusions

We identified three factors that affect colonoscope insertion time after left-sided colorectal resection, including the presence of a colostomy. Inexperienced endoscopists were much more affected by the presence of a colostomy after left-sided colorectal resection. These findings have implications for the practice and teaching of colonoscopy after left-sided colorectal resection.     

Association Between Red Cell Distribution Width and Disease Activity in Patients with Inflammatory Bowel Disease

Background  

Recent studies have suggested that a higher red blood cell distribution width (RDW) is associated with disease activity in patients with inflammatory bowel disease (IBD). However, the RDW in IBD patients without anemia has not been investigated.