Risk Factors for Survival after Lung Metastasectomy in Colorectal Cancer Patients: A Systematic Review and Meta-Analysis

Background

Resection of lung metastases (LM) from colorectal cancer (CRC) is increasingly performed with a curative intent. It is currently not possible to identify those CRC patients who may benefit the most from this surgical strategy. The aim of this study was to perform a systematic review of risk factors for survival after lung metastasectomy for CRC.

Methods

We performed a meta-analysis of series published between 2000 and 2011, which focused on surgical management of LM from CRC and included more than 40 patients each. Pooled hazard ratios (HR) were calculated by using random effects model for parameters considered as potential prognostic factors.

Results

Twenty-five studies including a total of 2925 patients were considered in this analysis. Four parameters were associated with poor survival: (1) a short disease-free interval between primary tumor resection and development of LM (HR 1.59, 95 % confidence interval [CI] 1.27–1.98); (2) multiple LM (HR 2.04, 95 % CI 1.72–2.41); (3) positive hilar and/or mediastinal lymph nodes (HR 1.65, 95 % CI 1.35–2.02); and (4) elevated prethoracotomy carcinoembryonic antigen (HR 1.91, 95 % CI 1.57–2.32). By comparison, a history of resected liver metastases (HR 1.22, 95 % CI 0.91–1.64) did not achieve statistical significance.

Conclusions

Clinical variables associated with prolonged survival after surgery for LM in CRC patients include prolonged disease-free interval between primary tumor and metastatic spread, normal prethoracotomy carcinoembryonic antigen, absence of thoracic node involvement, and a single pulmonary lesion.     

Four of the six Drosophila rhodopsin‐expressing photoreceptors can mediate circadian entrainment in low light

Light is the major stimulus for the synchronization of circadian clocks with day–night cycles. The light‐driven entrainment of the clock that controls rest–activity rhythms in Drosophila relies on different photoreceptive molecules. Cryptochrome (CRY) is expressed in most brain clock neurons, whereas six different rhodopsins (RH) are present in the light‐sensing organs. The compound eye includes outer photoreceptors that express RH1 and inner photoreceptors that each express one of the four rhodopsins RH3–RH6. RH6 is also expressed in the extraretinal Hofbauer–Buchner eyelet, whereas RH2 is only found in the ocelli. In low light, the synchronization of behavioral rhythms relies on either CRY or the canonical rhodopsin phototransduction pathway, which requires the phospholipase C‐β encoded by norpA (no receptor potential A). We used norpA^P24 cry⁰² double mutants that are circadianly blind in low light and restored NORPA function in each of the six types of photoreceptors, defined as expressing a particular rhodopsin. We first show that the NORPA pathway is less efficient than CRY for synchronizing rest–activity rhythms with delayed light–dark cycles but is important for proper phasing, whereas the two light‐sensing pathways can mediate efficient adjustments to phase advances. Four of the six rhodopsin‐expressing photoreceptors can mediate circadian entrainment, and all are more efficient for advancing than for delaying the behavioral clock. In contrast, neither RH5‐expressing retinal photoreceptors nor RH2‐expressing ocellar photoreceptors are sufficient to mediate synchronization through the NORPA pathway. Our results thus reveal different contributions of rhodopsin‐expressing photoreceptors and suggest the existence of several circuits for rhodopsin‐dependent circadian entrainment. J. Comp. Neurol. 524:2828–2844, 2016. © 2016 Wiley Periodicals, Inc.     

Liver-kidney recipients with chronic viral hepatitis C treated with interferon-alpha

Antiviral therapy with interferon-alpha (IFN-alpha) and pegylated IFN-alpha (PEG-IFN-alpha) for chronic hepatitis C (HCV)-infected kidney recipients remains controversial. IFN-alpha is not recommended in most cases because it induces severe acute graft rejection. However, IFN-alpha, as PEG-IFN-alpha, is associated with a more pronounced immune response, and is well tolerated in HCV-infected liver recipients without causing graft rejection. In combined liver-kidney transplant (LKT) recipients, IFN-alpha has been occasionally used and appears to be well tolerated. All LKT recipients with a functioning kidney and liver having a HCV replication and who needed IFN-alpha therapy have been included in the study. The occurrence of liver and/or renal acute rejection as well as the HCV replication has been collected. A total of 12 LKT patients treated with PEG-IFN-alpha plus ribavirin have been studied. No acute rejection was observed. Renal function remained stable during and after discontinuing treatment, without any graft dysfunction. Two patients had a partial viral response and four had a sustained viral response. All patients, whatever their viral response, had decreased liver-enzyme levels. Response to PEG-IFN-alpha therapy was correlated with steroid dose and transaminase level when PEG-IFN-alpha was started. These data suggest that the combination therapy of PEG-IFN-alpha plus ribavirin did not have a higher risk of acute kidney-graft rejection after liver-kidney transplantation.     

Fetal mouse skin heals scarlessly in a chick chorioallantoic membrane model system

In mammals, the early-gestation fetus has the regenerative ability to heal skin wounds without scar formation. This observation was first reported more than 3 decades ago, and has been confirmed in a number of in vivo animal models. Although an intensive research effort has focused on unraveling the mechanisms underlying scarless fetal wound repair, no suitable model of in vitro fetal skin healing has been developed. In this article, we report a novel model for the study of fetal wound healing. Fetal skin from gestational day 16.5 Balb/c mice (total gestation, 20 days) was grafted onto the chorioallantoic membrane of 12-day-old chicken embryos and cultured for up to 7 days. At 48 hours postengraftment, circular wounds (diameter = 1 mm) were made in the fetal skin using a rotating titanium sapphire laser (N = 45). The tissue was examined daily by visual inspection to look for signs of infection and ischemia. The grafts and the surrounding host tissue were examined histologically. In all fetal skin grafts, the wounds completely reepithelialized by postinjury day 7, with regeneration of the dermis. Fetal mouse skin xenografts transplanted onto the chorioallantoic membrane of fertilized chicken eggs provides a useful model for the study of fetal wound healing. This model can be used as an adjunct to traditional in vivo mammalian models of fetal repair.     

Technical refinement and learning curve for attenuating neurapraxia during robotic-assisted radical prostatectomy to improve sexual function

Background

While radical prostatectomy surgeon learning curves have characterized less blood loss, shorter operative times, and fewer positive margins, there is a dearth of studies characterizing learning curves for improving sexual function. Additionally, while learning curve studies often define volume thresholds for improvement, few of these studies demonstrate specific technical modifications that allow reproducibility of improved outcomes.

Objective

Demonstrate and quantify the learning curve for improving sexual function outcomes based on technical refinements that reduce neurovascular bundle displacement during nerve-sparing robot-assisted radical prostatectomy (RARP).

Design, setting, and participants

We performed a retrospective study of 400 consecutive RARPs, categorized into groups of 50, performed after elimination of continuous surgeon/assistant neurovascular bundle countertraction.

Surgical procedure

Our approach to RARP has been described previously. A single-console robotic system was used for all cases.

Outcome measurements and statistical analysis

Expanded Prostate Cancer Index Composite sexual function was measured within 1 yr of RARP. Linear regression was performed to determine factors influencing the recovery of sexual function.

Results and limitations

Greater surgeon experience was associated with better 5-mo sexual function (p = 0.007) and a trend for better 12-mo sexual function (p = 0.061), with improvement plateauing after 250–300 cases. Additionally, younger patient age (both p < 0.02) and better preoperative sexual function (<0.001) were associated with better 5- and 12-mo sexual function. Moreover, trainee robotic console time during nerve sparing was associated with worse 12-mo sexual function (p = 0.021), while unilateral nerve sparing/non–nerve sparing was associated with worse 5-mo sexual function (p = 0.009). Limitations include the retrospective single-surgeon design.

Conclusions

With greater surgeon experience, attenuating lateral displacement of the neurovascular bundle and resultant neurapraxia improve postoperative sexual function. However, to maximize outcomes, appropriate patient selection must be exercised when allowing trainee nerve-sparing involvement.     

Recurrence of Dislocation Following Total Hip Arthroplasty Revision Using Dual Mobility Cups Was Rare in 180 Hips Followed Over 7?Years

Background

Dual mobility (DM) cups of mobile polyethylene were introduced to prevent total hip arthroplasty (THA) dislocation, but no large series with this design to treat recurrent instability have been reported.

Purpose

Our retrospective investigation ascertained the efficiency of DM cups in correction of recurrent dislocation and assessed any adverse effects.

Methods

One hundred eighty THAs with recurrent instability were revised to DM cups in 180 patients (mean age, 67.4 ± 11.7 years; range, 19 to 92 years). Thirty-one patients (17.2%) underwent at least one earlier THA revision, and 15 (10.3%) incurred non-union of the greater trochanter. Of the initial group in 2009, 145 patients had completed evaluations which included assessment of the Harris Hip Score and a radiographic assessment at a mean follow-up of 7.7 ± 2.2 years (range, 4 to 14 years). The rate of survival was calculated considering any reason for revision as failure.

Results

At follow-up, Harris hip score was 83.9 ± 16.1 (range, 21 to 100). Dislocation of the large articulation occurred in seven hips (4.8%), and only two recurred (1.4%) (one requiring additional revision). In addition, two intra-prosthetic dislocations of the small articulation (1.4%) were observed and needed revision surgery. The large number of earlier surgeries and non-union of the greater trochanter were related to recurrent instability. Two cups (1.4%) showed signs of definite loosening; six (4.1%) presented signs of possible loosening. Twenty-nine hips manifested femoral or acetabular osteolysis (20%), but only three were severe. Eight-year survival rate considering revision for any reason was 92.6% (95% CI, 85.5–96.4%).

Conclusions

This series indicates that DM cups are a viable option to treat recurrent THA instability. Their design provides a low risk of recurrent instability without increasing mechanical complications.     

Subureteral polydimethylsiloxane injection versus extravesical reimplantation for primary low grade vesicoureteral reflux in children: a comparative study

PURPOSE: We compare the outcome of extravesical ureteral reimplantation to endoscopic polydimethylsiloxane (Macroplastique, Uroplasty, Inc., Minneapolis, Minnesota) subureteral injection for primary low grade vesicoureteral reflux in children. MATERIALS AND METHODS: Between 1997 and 2000, 180 patients underwent polydimethylsiloxane injection (74, 108 ureters) or extravesical ureteral reimplantation (106, 166 ureters) for low grade vesicoureteral reflux. Low grade reflux was defined as grades I to III. Outcome analysis included success rates, de novo hydronephrosis, voiding efficiency, urinary tract infections and complications. RESULTS: Mean patient age at surgery for the injection and surgery groups was 60 and 77 months, and mean followup was 12 and 15 months, respectively. Of the patients who underwent single injection 80.6% were cured of reflux at 3 months and 91.6% were cured at last followup. Success rate after reimplantation was 95.8% at 3 months which improved to 98.8% 1 year later. The success rate was significantly different between the injection and reimplantation groups at 3 and 12 months (p <0.01). Postoperative complications in the reimplantation group included transient urinary retention after bilateral surgery in 2 patients (3.3%), suprapubic fluid collections in 2 and wound seroma in 1. No complications occurred in the polydimethylsiloxane group. CONCLUSIONS: Extravesical ureteral reimplantation has near perfect success with a low but definite complication rate. Polydimethylsiloxane offers high success rates for reflux in an ambulatory setting with no short-term complications. Currently, endoscopic polydimethylsiloxane injection is our preferred mode of therapy for low grade vesicoureteral reflux in children when surgical correction is indicated.     

Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part I: technological concepts and evolution.

Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates geared to simplified preparation without biochemical blood handling. In this initial article, we describe the conceptual and technical evolution from fibrin glues to platelet concentrates. This retrospective analysis is necessary for the understanding of fibrin technologies and the evaluation of the biochemical properties of 3 generations of surgical additives, respectively fibrin adhesives, concentrated platelet-rich plasma (cPRP) and PRF. Indeed, the 3-dimensional fibrin architecture is deeply dependent on artificial clinical polymerization processes, such as massive bovine thrombin addition. Currently, the slow polymerization during PRF preparation seems to generate a fibrin network very similar to the natural one. Such a network leads to a more efficient cell migration and proliferation and thus cicatrization.