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Contrast-enhanced computed tomography colonography (CE-CTC) is a useful guide for the laparoscopic surgeon to avoid incorrectly removing the colonic segment and the failure to diagnose of synchronous colonic and extra-colonic lesions. Lymph node dissection and vessel ligation under a laparoscopic approach can be time-consuming and can damage vessels and organs. Moreover, mesenteric vessels have extreme variations in terms of their courses and numbers. We describe the benefit of using an abdominal vascular map created by CE-CTC in laparoscopic colorectal surgery candidates. We describe patients with different diseases (colorectal cancer, diverticular disease, and inflammatory bowel disease) who underwent CE-CTC just prior to laparoscopic surgery.  相似文献   
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Background

Survival estimation guides surgical decision-making in metastatic bone disease. Traditionally, classic scoring systems, such as the Bauer score, provide survival estimates based on a summary score of prognostic factors. Identification of new factors might improve the accuracy of these models. Additionally, the use of different algorithms—nomograms or boosting algorithms—could further improve accuracy of prognostication relative to classic scoring systems. A nomogram is an extension of a classic scoring system and generates a more-individualized survival probability based on a patient’s set of characteristics using a figure. Boosting is a method that automatically trains to classify outcomes by applying classifiers (variables) in a sequential way and subsequently combines them. A boosting algorithm provides survival probabilities based on every possible combination of variables.

Questions/purposes

We wished to (1) assess factors independently associated with decreased survival in patients with metastatic long bone fractures and (2) compare the accuracy of a classic scoring system, nomogram, and boosting algorithms in predicting 30-, 90-, and 365-day survival.

Methods

We included all 927 patients in our retrospective study who underwent surgery for a metastatic long bone fracture at two institutions between January 1999 and December 2013. We included only the first procedure if patients underwent multiple surgical procedures or had more than one fracture. Median followup was 8 months (interquartile range, 3-25 months); 369 of 412 (90%) patients who where alive at 1 year were still in followup. Multivariable Cox regression analysis was used to identify clinical and laboratory factors independently associated with decreased survival. We created a classic scoring system, nomogram, and boosting algorithms based on identified variables. Accuracy of the algorithms was assessed using area under the curve analysis through fivefold cross validation.

Results

The following factors were associated with a decreased likelihood of survival after surgical treatment of a metastatic long bone fracture, after controlling for relevant confounding variables: older age (hazard ratio [HR], 1.0; 95% CI, 1.0–1.0; p < 0.001), additional comorbidity (HR, 1.2; 95% CI, 1.0–1.4; p = 0.034), BMI less than 18.5 kg/m2 (HR, 2.0; 95% CI, 1.2–3.5; p = 0.011), tumor type with poor prognosis (HR, 1.8; 95% CI, 1.6–2.2; p < 0.001), multiple bone metastases (HR, 1.3; 95% CI, 1.1–1.6; p = 0.008), visceral metastases (HR, 1.6; 95% CI, 1.4–1.9; p < 0.001), and lower hemoglobin level (HR, 0.91; 95% CI, 0.87–0.96; p < 0.001). The survival estimates by the nomogram were moderately accurate for predicting 30-day (area under the curve [AUC], 0.72), 90-day (AUC, 0.75), and 365-day (AUC, 0.73) survival and remained stable after correcting for optimism through fivefold cross validation. Boosting algorithms were better predictors of survival on the training datasets, but decreased to a performance level comparable to the nomogram when applied on testing datasets for 30-day (AUC, 0.69), 90-day (AUC, 0.75), and 365-day (AUC, 0.72) survival prediction. Performance of the classic scoring system was lowest for all prediction periods.

Conclusions

Comorbidity status and BMI are newly identified factors associated with decreased survival and should be taken into account when estimating survival. Performance of the boosting algorithms and nomogram were comparable on the testing datasets. However, the nomogram is easier to apply and therefore more useful to aid surgical decision making in clinical practice.

Level of Evidence

Level III, prognostic study.

Electronic supplementary material

The online version of this article (doi:10.1007/s11999-015-4446-z) contains supplementary material, which is available to authorized users.  相似文献   
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Leiomyomas (LMs) may appear throughout the entire gastrointestinal tract but are rarely seen in the colon-rectum and only 5 of those measured greater than 15 cm in diameter. Pain and palpable abdominal mass are the most common symptoms. Surgical resection is the treatment of choice for most LMs. We here describe a case of a 46-year-old woman who presented with a 3-month history of abdominal pain associated with worsening constipation and abdominal distension. A pelvic solid, polylobulate, left-sided mass was noted on examination. Preoperative findings revealed a dishomogeneous sigmoid mass with calcified spots compressing small intestine and bladder. At laparotomy, a large polylobulate and well-circumscribed mass arising from the descending colon mesentery and displacing small intestine, uterus, and ovaries. A segmental colon resection was performed. An extraluminal 18- × 12- × 5-cm paucicellular sigmoid colon leiomyoma was histologically diagnosed. Our case is one of the few giant (>15 cm) sigmoid colon LMs reported in the literature. Although rare and benign in nature, LMs of the colon can cause life-threatening complications that could require emergency treatment and they should be included in the differential diagnosis of large abdominopelvic masses. Follow-up after surgery is necessary for tumors with any atypia or mitotic activity.Key words: Leiomyoma, Digestive tract, Bowel obstruction, Pelvic massPrimary leiomyomas (LMs) present most commonly in the female genital tract and skin but they are rarely seen in the colon-rectum. Macroscopically, LMs may be intraluminal, intramural, extramural, or dumbbell.1,2 The majority of LMs remain asymptomatic until they have reached a large size: most common symptoms are pain and palpable abdominal mass.1,2 Symptomatic left colon LMs are uncommon and only 5 of those reported in the literature measured greater than 15 cm in diameter.1 Histologically, most of them arise from the muscularis propria.1,3 The most important differential diagnoses are malignant leiomyosarcoma and gastrointestinal stromal tumors (GIST).1,3 Surgical resection is the treatment of choice for large LMs: complete excision should be always attempted and follow up is necessary for tumors with any atypia or mitotic activity.1,2 Although rare and benign in nature, LMs of the colon can cause life-threatening complications that require emergency treatment.13 We here describe a case of large extraluminal sigmoid colon LM causing pain and worsening bowel obstruction.  相似文献   
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Granulocyte‐monocyte apheresis (GMA) is an emerging therapeutic option in active course of ulcerative colitis (UC). Appropriate GMA dose, including total number, frequency, and duration of the individual GMA session, is a matter of debate. It was the aim of the present study to evaluate the efficacy of a dose‐intensified GMA regimen in patients with moderately to severely active UC. A prospective open‐label, single‐center study was performed in 10 patients with active UC (Rachmilewitz Clinical Activity Index [CAI] ≥ 8 points; Rachmilewitz Endoscopic Index ≥ 7 points). Patients had failed to improve after treatment with steroids and/or immunomodulators. GMA was performed twice weekly for 2 h to a maximum of 10 sessions. In each GMA session, the adsorber was changed after 1 h of treatment time. Four patients achieved remission with a CAI ≤ 4 points. Three patients had a response with an improvement of CAI of ≥3 points. Three patients showed no benefit from GMA. The quality of life score determined by the inflammatory bowel disease questionnaire‐Deutschland increased by 26 points in median. First and second filters had similar efficiency in granulocyte and monocyte adsorption. No major adverse effects were observed. Dose‐intensified GMA as reported in this study provided an encouraging short‐term response rate of 70% in patients with moderately to severely active UC not responding to standard steroid or immunomodulator therapy. Although all patients relapsed not later than 16 weeks, GMA might be useful to reduce steroid and immunomodulator usage, or to delay surgery in this patient group.  相似文献   
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