Adjuvant Radiotherapy Use by US Radiation Oncologists After Radical Cystectomy for Muscle-invasive Bladder Cancer

Application of nanotechnology in bladder cancer diagnosis and therapeutic drug delivery

Bladder cancer (BC) is one of the most common malignant tumors in the urinary system, and its high recurrence rate is a great economic burden to patients. Traditional diagnosis and treatment methods have the disadvantages of insufficient targeting, obvious side effects and low sensitivity, which seriously limit the accurate diagnosis and efficient treatment of BC. Due to their small size, easy surface modification, optical properties such as plasmon resonance, and surface enhanced Raman scattering, good electrical conductivity and photothermal conversion properties, nanomaterials have great potential application value in the realization of specific diagnosis and targeted therapy of BC. At present, the application of nanomaterials in the diagnosis and treatment of BC is attracting great attention and achieving rich research results. Therefore, this paper summarizes the recent research on nanomaterials in the diagnosis and treatment of BC, clarifies the existing advantages and disadvantages, and provides theoretical guidance for promoting the accurate diagnosis and efficient treatment of BC.

A Novel DNA Methylation Signature as an Independent Prognostic Factor in Muscle-Invasive Bladder Cancer

Background

Muscle-invasive bladder cancer (MIBC) accounts for approximately 20% of all urothelial bladder carcinomas (UBC) at time of diagnosis, and up to 30% of patients with non-muscle invasive UBC will progress to MIBC over time. An increasing body of evidence has revealed a strong correlation between aberrant DNA methylation and tumorigenesis in MIBC.

Results

Using The Cancer Genome Atlas (TCGA) molecular data for 413 patients, we described a DNA methylation-based signature as a prognostic factor for overall survival (OS) in MIBC patients. By using a least absolute shrinkage and selection operator (LASSO) model, differentially methylated regions were first identified using multiple criteria followed by survival and LASSO analyses to identify DNA methylation probes related to OS and build a classifier to stratify patients with MIBC. The prognostic value of the classifier, referred to as risk score (RS), was validated in a held-out testing set from the TCGA MIBC cohort. Finally, receiver operating characteristic (ROC) analysis was used to compare the prognostic accuracy of the models built with RS alone, RS plus clinicopathologic features, and clinicopathologic features alone. We found that our seven-probe classifier-based RS stratifies patients into high- and low-risk groups for overall survival (OS) in the testing set (n = 137) (AUC at 3 years, 0.65; AUC at 5 years, 0.65). In addition, RS significantly improved the prognostic model when it was combined with clinical information including age, smoking status, Tumor (T) stage, and Lymph node metastasis (N) stage.

Conclusions

The DNA methylation-based RS can be a useful tool to predict the accuracy of preoperative and/or post-cystectomy models of OS in MIBC patients.

Cardiac Monitoring for Thoracic Radiation Therapy: Survey of Practice Patterns in the United States

OBJECTIVE

The American Society of Clinical Oncology (ASCO) 2017 guidelines on cardiac monitoring during cancer treatments identified patients receiving thoracic radiation (TRT) ≥30 Gy (heart in field) at increased risk for developing radiation-induced heart disease (RIHD). ASCO encouraged clinicians to actively screen and monitor for baseline modifiable cardiac risk factors and therapy-induced cardiotoxicity in this high-risk population. Coronary artery calcium (CAC) is an independent risk factor for adverse cardiac events that can be mitigated with preventative medical therapy. It is unclear whether radiation oncologists (ROs) are aware of ASCO guidelines or the implications of CAC observed on computed tomographic scans. We report on practice patterns, perceptions, and experiences of cardiac monitoring for patients receiving definitive TRT, excluding breast patients.

MATERIALS AND METHODS

A 28-question survey was emailed to United States ROs 3 times from September 2018 to January 2019.

RESULTS

There were 162 respondents from 42 states, 51% in academic practice. Most ROs (81%) were not aware of the ASCO guidelines. Only 24% agreed with the guidelines, only 27% believed symptomatic RIHD could manifest within 2 years of TRT, and 69% thought there was a lack of strong evidence for type and timing of cardiac monitoring tests. If CAC was evident on computed tomographic scans, 40% took no further action to inform the patient or referring doctor.

CONCLUSIONS

This survey highlights a critical gap in knowledge about cardiac monitoring and potentially life-saving opportunities for preventive cardiac medical management. Future studies focusing on timing and detection of RIHD may elucidate the utility of cardiac monitoring for TRT patients.

Trimodality therapy for bladder cancer: modern management and future directions

PURPOSE OF REVIEW

This review examines both trimodality therapy (TMT) in the definitive management of bladder cancer as well as the use of adjuvant radiotherapy for bladder cancer with a specific focus on publications from the last 2 years.

RECENT FINDINGS

TMT is an effective management strategy for muscle invasive bladder cancer with outcomes similar to radical cystectomy. Effectiveness of this strategy exists in variant histologies and can be personalized with use of biomarkers. There is a role for adjuvant radiotherapy in locally advanced bladder cancer, especially in the age of improved imaging and modern radiotherapy techniques.

SUMMARY

This review should provide the reader data necessary to support use of TMT and adjuvant radiation therapy in their clinic.

The Role of Adjuvant Radiation Therapy in Locally Advanced Bladder Cancer

Background:

The standard of care for locally advanced bladder cancer (LABC) is neoadjuvant chemotherapy followed by cystectomy. However, the role of adjuvant therapy for locally advanced bladder cancer is unclear.

Objective:

The purpose of this study was to evaluate the outcomes of adjuvant radiation therapy (RT) for patients with LABC, and to determine which risk factors best predict for patients who may best benefit from adjuvant RT.

Methods:

The National Cancer Data Base (NCDB) was queried (2004– 2013) for patients with newly-diagnosed pT3-4N0-3M0 urothelial carcinoma of the bladder that received neoadjuvant chemotherapy and cystectomy. Patients were divided into two groups based on the adjuvant therapy they received: RT or observation. Statistics included multivariable logistic regression to determine factors predictive of receiving adjuvant RT, Kaplan-Meier analysis to evaluate overall survival (OS), and Cox proportional hazards modeling to determine variables associated with OS.

Results:

Altogether, 1,646 patients met inclusion criteria; 59 (3.6%) patients received adjuvant RT, while 1,587 (96.4%) were observed. Patients treated with adjuvant RT were more likely to be female, have positive surgical margins, and receive treatment at a non-academic facility. There was no difference in median overall survival (OS) between patients treated with RT when compared to patients observed (17.7 months vs. 23.5 months; p = 0.085). However, an improvement in median OS with the use of adjuvant RT was observed among patients with positive surgical margins (20.3 months vs. 13.1 months; p = 0.032). On multivariate analysis, advancing age, pT4 stage, positive N stage, positive margins, and lower socioeconomic status were associated with worse OS.

Conclusions:

In the largest study to date evaluating efficacy of adjuvant radiotherapy in patients with locally advanced bladder cancer, use of RT was not associated with OS in all patients, while RT was associated with improvemed OS among patients with positive surgical margins. Prospective studies are recommended to confirm these findings.

Current Practice Patterns Surrounding Fertility Concerns in Stage I Seminoma Patients: Survey of United States Radiation Oncologists

PURPOSE

Patients with testicular seminoma may face fertility issues because of their underlying disease as well as treatments they undergo. The current patterns of practice among U.S. radiation oncologists aimed at assessing and preserving fertility in patients with Stage I seminoma are unknown.

METHODS

We surveyed practicing U.S. radiation oncologists via an Institutional Review Board-approved online questionnaire. Respondents' characteristics and perceived patient infertility rates were analyzed for association with treatment recommendations.

RESULTS

We received 353 responses, of whom one quarter (23%) consider themselves experts. A vast majority (84%) recommend observation as a default strategy. Fifty-two percent routinely advise fertility assessment for patients before observation or chemotherapy, and 74% routinely do so before adjuvant radiation therapy (RT). Forty-one percent and 43% believe that 10% and 30% of patients are infertile following orchiectomy, respectively. Thirty-seven percent and 22% believe infertility rates following para-aortic RT to be 30% and 50%, respectively. Eighty percent routinely use clamshell scrotal shielding. Responders with higher perceived infertility rates are more likely to recommend fertility assessment/sperm banking (Fisher's exact p < 0.0001). Responders who routinely advised fertility assessment were more likely to use clamshell shielding (Cochran-Armitage trend test p = 0.0007). Clamshell use was positively correlated with higher perceived infertility rates following para-aortic RT (Spearman's correlation coefficient = 0.006).

CONCLUSIONS

Despite a clear knowledge of fertility issues in men diagnosed with seminoma, there is no universal adoption of fertility assessment among U.S. radiation oncologists.