Treatment of Urethral Strictures from Irradiation and Other Nonsurgical Forms of Pelvic Cancer Treatment. Adv Urol. 2015;2015:476390. [PMID: 26494994 PMCID: PMC4606407 DOI: 10.1155/2015/476390]

Voxel-level biological optimisation of prostate IMRT using patient-specific tumour location and clonogen density derived from mpMRI

AIMS

This study aimed to develop a framework for optimising prostate intensity-modulated radiotherapy (IMRT) based on patient-specific tumour biology, derived from multiparametric MRI (mpMRI). The framework included a probabilistic treatment planning technique in the effort to yield dose distributions with an improved expected treatment outcome compared with uniform-dose planning approaches.

METHODS

IMRT plans were generated for five prostate cancer patients using two inverse planning methods: uniform-dose to the planning target volume and probabilistic biological optimisation for clinical target volume tumour control probability (TCP) maximisation. Patient-specific tumour location and clonogen density information were derived from mpMRI and geometric uncertainties were incorporated in the TCP calculation. Potential reduction in dose to sensitive structures was assessed by comparing dose metrics of uniform-dose plans with biologically-optimised plans of an equivalent level of expected tumour control.

RESULTS

The planning study demonstrated biological optimisation has the potential to reduce expected normal tissue toxicity without sacrificing local control by shaping the dose distribution to the spatial distribution of tumour characteristics. On average, biologically-optimised plans achieved 38.6% (p-value: < 0.01) and 51.2% (p-value: < 0.01) reduction in expected rectum and bladder equivalent uniform dose, respectively, when compared with uniform-dose planning.

CONCLUSIONS

It was concluded that varying the dose distribution within the prostate to take account for each patient's clonogen distribution was feasible. Lower doses to normal structures compared to uniform-dose plans was possible whilst providing robust plans against geometric uncertainties. Further validation in a larger cohort is warranted along with considerations for adaptive therapy and limiting urethral dose.

A Comprehensive Review Emphasizing Anatomy, Etiology, Diagnosis, and Treatment of Male Urethral Stricture Disease

To date, urethral stricture disease in men, though relatively common, represents an often poorly managed condition. Therefore, this article is dedicated to encompassing the currently existing data upon anatomy, etiology, symptoms, diagnosis, and treatment of the disease, based on more than 40 years of experience at a tertiary referral center and a PubMed literature review enclosing publications until September 2018.

Development of a novel indwelling catheter for urethral surgery

This study aimed to develop an indwelling catheter that can be used for urethral flushing, urethral secretion drainage, local urethral drug delivery, and urine drainage.We designed a new indwelling catheter type that has a balloon, 4 peripheral grooves, and a C-shaped groove on its surface. In addition, there is a flushing channel, a balloon channel, and a urine drainage channel in the catheter body. However, the most critical characteristic is that the flushing channel and the 4 peripheral grooves are connected with the C-shaped groove, and the flushing liquid can reach the C-shaped groove through the flushing channel and then flow out through the peripheral grooves, while the balloon channel leads to the balloon. Generally, our design is to add 4 peripheral grooves, a C-shaped groove, and a flushing channel to the indwelling catheter that is applied clinically nowadays.We designed a new type of indwelling catheter, which is multifunctional, and we had acquired a national patent in China. In theory, the new catheter type cannot only be used for urine drainage, bladder irrigation, but also for urethral flushing, urethral excretion drainage, and local urethral drug delivery at the same time.This new indwelling catheter can theoretically reduce catheter-associated urinary tract infection and facilitate urethral secretion drainage or flushing out, which is especially suitable for the treatment and nursing of patients who underwent urethral operation. However, the new catheter have not been produced and tested clinically, and this is our next step.

Functional outcomes after prostatic cryosurgery

OBJECTIVE

To assess the functional effects of prostatic cryosurgery on micturition.

MATERIAL AND METHODS

Prospective study of men who underwent cryosurgery (CS) for prostate cancer between 2013 - 2015. Low urinary tract symptoms (LUTS) and quality of life (QoL) were assessed 1 month before surgery using IPSS questionnaire, a three-day voiding diary (3DVD) and uroflowmetry with ultrasound-measured postvoid residual volume. Need of medical treatment for LUTS was also recorded. The same assessment was performed at 3, 6 and 12 months after CS. Outcomes after surgery were compared to those prior to surgery.

RESULTS

Forty-five patients underwent a CS during the study period, of whom 25 patients could be recruited in the study. Mean age was 73.5 years (range 66-84). Nineteen CS (76%) were performed as a primary procedure, while 6 CS (24%) as a salvage procedure. No statistical differences were found comparing results of IPSS, QoL, D3vd or uroflowmetry and PVR at 3, 6 or 12 months after CS compared to before surgery. Before CS, 8 (32%) patients were on medical treatment for LUTS, while at 6 and 12 months after surgery, 3 (13.6%) and 2 (9.5%) patients required some medication, respectively.

CONCLUSION

According to the punctuation of IPSS, QoL questionnaire, and a 3-day voiding diary, LUTS does not worsen after CS. Prostatic cryosurgery does not seem to impact uroflowmetry results.

Renal function and urological complications after radical hysterectomy with postoperative radiotherapy and platinum-based chemotherapy for cervical cancer

Background

We aimed to clarify renal functional changes long term and serious urological complications in women with cervical cancer who undergo radical hysterectomy followed by pelvic radiotherapy and/or platinum-based chemotherapy to treat the initial disease.

Methods

Data on 380 women who underwent radical hysterectomy at the National Kyushu Cancer Center from January 1997 to December 2013 were reviewed. Main outcome measures were the estimated glomerular filtration rate (eGFR) and monitored abnormal urological findings.

Results

Postoperative eGFR was significantly lower than preoperative eGFR in 179 women with surgery alone and in 201 women with additional pelvic radiotherapy and/or chemotherapy (both P < 0.01). Two types of univariate analyses for eGFR reduction in women after treatment showed that older age, advanced stage, pelvic radiotherapy, and platinum-based chemotherapy were significant variables on both analyses. Two types of multivariate analyses showed that platinum-based chemotherapy or pelvic radiotherapy were associated with impaired renal function (odds ratio 1.96, 95% confidence interval 1.08-3.54 and odds ratio 2.85, 95% confidence interval 1.12-7.24, for the respective analyses). There was a higher rate of bladder wall thickening in women with pelvic radiotherapy had than those without it (17.4% vs. 2.7%, P < 0.01). One serious urological complication (intraperitoneal rupture of the bladder) occurred among women who underwent pelvic radiotherapy (0.6% vs. 0%).

Conclusions

Surgeons should be aware that eGFR is reduced after platinum-based chemotherapy and/or postoperative pelvic radiotherapy. Serious and life-threatening urological complications are rare, but surgeons should be aware of the possibility during the long follow-up.

Disease- and Treatment-related Complication on F-18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Oncology Practice: A Pictorial Review

F-18-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) is routinely performed in oncology patients for various indications including staging, restaging, recurrence detection, and treatment response evaluation. Many disease- and treatment-related complications can be incidentally detected on PET/CT, which may be due to the complication of radiotherapy, chemotherapy, intervention, or primary tumor itself. Some of these complications could be life threatening and need urgent intervention. Therefore, these incidental findings should be recognized on PET/CT and immediately informed to the treating physicians if required urgent intervention.

Management of bladder neck stenosis and urethral stricture and stenosis following treatment for prostate cancer

The aim of this review is to examine all urethral strictures and stenoses subsequent to treatment for prostate cancer, including radical prostatectomy (RP), radiotherapy, high intensity focused ultrasound (HIFU) and cryotherapy. The overall majority respond to endoscopic treatment, including dilatation, direct visual internal urethrotomy (DVIU) or bladder neck incision (BNI). There are adjunct treatments to endoscopic management, including injections of corticosteroids and mitomycin C (MMC) and urethral stents, which remain controversial and are not currently mainstay of treatment. Recalcitrant strictures are most commonly managed with urethroplasty, while recalcitrant stenosis is relatively rare yet almost always associated with bothersome urinary incontinence, requiring bladder neck reconstruction and subsequent artificial urinary sphincter (AUS) implantation, or urinary diversion for the devastated outlet.

Endoscopic and non-endoscopic approaches for the management of radiation-induced rectal bleeding

Pelvic radiation is a commonly utilized treatment for malignancy of the genitourinary and lower gastrointestinal tract. Radiation proctitis and the resultant clinical picture varies from asymptomatic to potentially life threatening. Similarly, treatment options also vary greatly, from medical therapy to surgical intervention. Commonly utilized medical therapy includes sucralfate enemas, antibiotics, 5-aminosalicylic acid derivatives, probiotics, antioxidants, short-chain fatty acids, formalin instillation and fractionated hyperbaric oxygen. More invasive treatments include endoscopic-based, focally ablative interventions such as dilation, heater and bipolar cautery, neodymium/yttrium aluminum garnet argon laser, radiofrequency ablation or argon plasma coagulation. Despite its relatively common frequency, there is a dearth of existing literature reporting head-to-head comparisons of the various treatment options via a randomized controlled approach. The purpose of our review was to present the reader a consolidation of the existing evidence-based literature with the goal of highlighting the comparative effectiveness and risks of the various treatment approaches. Finally, we outline a pragmatic approach to the treatment of radiation proctitis. In light of the lack of randomized data, our goal is to pursue as least invasive an approach as possible, with escalation of care tailored to the severity of the patient’s symptoms. For those cases that are clinically asymptomatic or only mildly symptomatic, observation or medical management can be considered. Once a patient fails such management or symptoms become more severe, invasive procedures such as endoscopically based focal ablation or surgical intervention can be considered. Although not all recommendations are supported by level I evidence, reported case series and single-institutional studies in the literature suggest that successful treatment with cessation of symptoms can be obtained in the majority of cases.

Improving Outcomes of Bulbomembranous Urethroplasty for Radiation-induced Urethral Strictures in Post-Urolume Era

OBJECTIVE

To evaluate contemporary outcomes of excision and primary anastomosis (EPA) for the treatment of radiation-induced urethral strictures (RUS).

PATIENTS AND METHODS

A retrospective review of 72 patients undergoing EPA for RUS from 2007 to 2015 by a single surgeon was performed. We analyzed overall and long-term success rates of EPA urethroplasty and compared patient cohorts from two groups, 2007-2012 vs 2013-2015 (post-Urolume).

RESULTS

During the course of the study, we noted a near doubling of patient volume from the earlier (6.2 patients/year) to later (11.7 patients/year) cohorts. Among the 37 men treated from 2007 to 2012, we identified an EPA success rate of 70% compared with the improved 86% success rate in the subsequent cohort of 35 men treated from 2013 to 2015 (P = .07). Single dilation was successful in 50% of initial and 40% of subsequent cohort patients in the treatment of recurrence. Initial and subsequent cohorts varied only in regard to stricture length (mean 2.0 cm vs 3.0 cm in initial and subsequent cohorts, P = .001) and number treated with Urolume stent (initial 5 vs none in the later cohort, P = .03). Length of follow-up (median 50 [17-97] months for the initial and 22 [6-34] months for the later cohort) was not associated with recurrence.

CONCLUSION

Increasing numbers of RUS patients are presenting for urethral reconstruction in the post-Urolume era. With increasing experience, we improved success rates of EPA urethroplasty to over 85% despite increased stricture length.

Prediction of In-hospital Mortality in Emergency Department Patients With Sepsis: A Local Big Data-Driven, Machine Learning Approach

OBJECTIVES

Predictive analytics in emergency care has mostly been limited to the use of clinical decision rules (CDRs) in the form of simple heuristics and scoring systems. In the development of CDRs, limitations in analytic methods and concerns with usability have generally constrained models to a preselected small set of variables judged to be clinically relevant and to rules that are easily calculated. Furthermore, CDRs frequently suffer from questions of generalizability, take years to develop, and lack the ability to be updated as new information becomes available. Newer analytic and machine learning techniques capable of harnessing the large number of variables that are already available through electronic health records (EHRs) may better predict patient outcomes and facilitate automation and deployment within clinical decision support systems. In this proof-of-concept study, a local, big data-driven, machine learning approach is compared to existing CDRs and traditional analytic methods using the prediction of sepsis in-hospital mortality as the use case.

METHODS

This was a retrospective study of adult ED visits admitted to the hospital meeting criteria for sepsis from October 2013 to October 2014. Sepsis was defined as meeting criteria for systemic inflammatory response syndrome with an infectious admitting diagnosis in the ED. ED visits were randomly partitioned into an 80%/20% split for training and validation. A random forest model (machine learning approach) was constructed using over 500 clinical variables from data available within the EHRs of four hospitals to predict in-hospital mortality. The machine learning prediction model was then compared to a classification and regression tree (CART) model, logistic regression model, and previously developed prediction tools on the validation data set using area under the receiver operating characteristic curve (AUC) and chi-square statistics.

RESULTS

There were 5,278 visits among 4,676 unique patients who met criteria for sepsis. Of the 4,222 patients in the training group, 210 (5.0%) died during hospitalization, and of the 1,056 patients in the validation group, 50 (4.7%) died during hospitalization. The AUCs with 95% confidence intervals (CIs) for the different models were as follows: random forest model, 0.86 (95% CI = 0.82 to 0.90); CART model, 0.69 (95% CI = 0.62 to 0.77); logistic regression model, 0.76 (95% CI = 0.69 to 0.82); CURB-65, 0.73 (95% CI = 0.67 to 0.80); MEDS, 0.71 (95% CI = 0.63 to 0.77); and mREMS, 0.72 (95% CI = 0.65 to 0.79). The random forest model AUC was statistically different from all other models (p ≤ 0.003 for all comparisons).

CONCLUSIONS

In this proof-of-concept study, a local big data-driven, machine learning approach outperformed existing CDRs as well as traditional analytic techniques for predicting in-hospital mortality of ED patients with sepsis. Future research should prospectively evaluate the effectiveness of this approach and whether it translates into improved clinical outcomes for high-risk sepsis patients. The methods developed serve as an example of a new model for predictive analytics in emergency care that can be automated, applied to other clinical outcomes of interest, and deployed in EHRs to enable locally relevant clinical predictions.