Chronic liver disease is not associated with statin prescription in a primary care cohort

Statins have historically been underutilized in patients with chronic liver disease (CLD). We sought to investigate the association between CLD and statin prescription in a primary care setting. Our retrospective cohort study identified primary care patients with a low-density lipoprotein value and more than one office visit from 2012 through 2018. Indication for statin therapy was determined using the Third Adult Treatment Panel criteria prior to November 2016 and the American College of Cardiology and American Heart Association guidelines thereafter. Indication for statin prescription and statin therapy by year was determined. Patients with CLD were identified using ICD-9/10 diagnosis codes. In total, 2119 individuals with an indication for statin therapy were identified. Of these individuals, 354 (16.7%) had CLD. Alcoholic and nonalcoholic fatty liver disease comprised 44.9% and 28.5% of the CLD population, respectively; 27.7% had cirrhosis. There was no difference in the prevalence of statin prescriptions when comparing patients with a CLD diagnosis to those without one (57.9 vs 59.9%, p = 0.48). A diagnosis of CLD was also not significantly associated with statin prescription when adjusting for other covariates (odds ratio (OR) 1.02; 95% confidence interval (CI) 0.78-1.33). An alanine aminotransferase level greater than 45 U/L significantly reduced the odds of a statin prescription (OR 0.62; 95% CI 0.44-0.87). Overall, the presence of a CLD diagnosis was not associated with attenuated statin utilization compared to those without a CLD diagnosis. Nevertheless, adherence to guideline indicated statin therapy remains suboptimal and efforts to increase statin utilization in this high-risk population remain prudent.

Gaps in Confirmatory Fibrosis Risk Assessment in Primary Care Patients with Nonalcoholic Fatty Liver Disease

BACKGROUND

As recommendations for non-invasive fibrosis risk assessment in nonalcoholic fatty liver disease (NAFLD) emerge, it is not known how often they are performed in primary care.

AIMS

We investigated the completion of confirmatory fibrosis risk assessment in primary care patients with NAFLD and indeterminate-risk or greater Fibrosis-4 Index (FIB-4) and NAFLD Fibrosis Scores (NFS).

METHODS

This retrospective cohort study of electronic health record data from a primary care clinic identified patients with diagnoses of NAFLD from 2012 through 2021. Patients with a diagnosis of a severe liver disease outcome during the study period were excluded. The most recent FIB-4 and NFS scores were calculated and categorized by advanced fibrosis risk. Charts were reviewed to identify the outcome of a confirmatory fibrosis risk assessment by liver elastography or liver biopsy for all patients with indeterminate-risk or higher FIB-4 (≥ 1.3) and NFS (≥ - 1.455) scores.

RESULTS

The cohort included 604 patients diagnosed with NAFLD. Two-thirds of included patients (399) had a FIB-4 or NFS score greater than low-risk, 19% (113) had a high-risk FIB-4 (≥ 2.67) or NFS (≥ 0.676) score, and 7% (44) had high-risk FIB-4 and NFS values. Of these 399 patients with an indication for a confirmatory fibrosis test, 10% (41) underwent liver elastography (24) or liver biopsy (18) or both (1).

CONCLUSIONS

Advanced fibrosis is a key indicator of future poor health outcomes in patients with NAFLD and a critical signal for referral to hepatology. Significant opportunities exist to improve confirmatory fibrosis risk assessment in patients with NAFLD.

Clinical Utility of Genomic Recurrence Risk Stratification in Early, Hormone-Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer: Real-World Experience

BACKGROUND

RNA-based genomic risk assessment estimates chemotherapy benefit in patients with hormone-receptor positive (HR+)/Human Epidermal Growth Factor 2-negative (ERBB2-) breast cancer (BC). It is virtually used in all patients with early HR+/ERBB2- BC regardless of clinical recurrence risk.

PATIENTS AND METHODS

We conducted a retrospective chart review of adult patients with early-stage (T1-3; N0; M0) HR+/ERBB2- BC who underwent genomic testing using the Oncotype DX (Exact Sciences) 21-genes assay. Clinicopathologic features were collected to assess the clinical recurrence risk, in terms of clinical risk score (CRS) and using a composite risk score of distant recurrence Regan Risk Score (RRS). CRS and RRS were compared to the genomic risk of recurrence (GRS).

RESULTS

Between January 2015 and December 2020, 517 patients with early-stage disease underwent genomic testing, and clinical data was available for 501 of them. There was statistically significant concordance between the 3 prognostication methods (P < 0.01). Within patients with low CRS (n = 349), 9.17% had a high GRS, compared to 8.93% in patients with low RRS (n = 280). In patients with grade 1 histology (n = 130), 3.85% had a high GRS and 68.46% had tumors > 1 cm, of whom only 4.49% had a high GRS. Tumor size > 1cm did not associate with a high GRS.

CONCLUSION

Genomic testing for patients with grade 1 tumors may be safely omitted, irrespective of size. Our finds call for a better understanding of the need for routine genomic testing in patients with low grade/low clinical risk of recurrence.

Predictive capacity of a miRNA panel in identifying teratoma in post-chemotherapy consolidation surgeries

Objectives

To investigate the utility of a novel serum miRNA biomarker panel to distinguish teratoma from nonmalignant necrotic/fibrotic tissues or nonviable tumours in patients with NSGCT undergoing post-chemotherapy consolidation surgery.

Patients and methods

We prospectively collected pre-surgical serum samples from 22 consecutive testicular NSGCT patients with residual NSGCT after chemotherapy undergoing post-chemotherapy consolidation surgery. We measured serum miRNA expression of four microRNAs (miRNA-375, miRNA-200a-3p, miRNA-200a-5p and miRNA-200b-3p) and compared with pathologic findings at time of surgery. Receiver operating characteristic (ROC) curves were performed to assess the ability of these miRNA to differentiate between teratoma and necrosis or viable malignancy.

Results

Twenty-two patients with NSGCT were split into two groups based on pathology at time of post-chemotherapy consolidation surgery (teratoma group vs. necrosis/fibrosis/viable tumour group, i.e., NFVT). Patients with teratoma were older at diagnosis compared with those patients with NFVT (median age 28.7 vs. 23.9). Patients with NFVT were more likely to have embryonal carcinoma in their primary tumour (81.8% vs. 27.3%; p = 0.01). The majority of patients in both groups were stage III (63.6% vs. 72.7%). In this analysis, none of the miRNAs had good sensitivity or specificity to predict teratoma. There was no significant association between the expression levels of the miRNAs and the presence of teratoma. There was no statistically significant correlation between any of the miRNAs and teratoma size.

Conclusion

This novel miRNA panel (miRNA-375, miRNA-200a-3p, miRNA-200a-5p and miRNA-200b-3p) did not distinguish teratoma from nonmalignant necrotic/fibrotic tissues or nonviable tumours in patients with NSGCT undergoing post-chemotherapy consolidation surgery.

Clinical utility of genomic recurrence risk stratification in early, hormone receptor–positive, human epidermal growth factor receptor 2–negative breast cancer

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Background: RNA-based genomic assessment of recurrence risk is used to estimate chemotherapy benefit in patients with hormone-receptor positive (HR+)/Human Epidermal Growth Factor 2-negative ( ERBB2-) breast cancer (BC). While originally validated in patients who met established clinicopathologic guidelines for consideration of adjuvant chemotherapy, it is virtually used in all patients with early HR+/ ERBB2- BC regardless of clinical recurrence risk. Methods: We conducted a retrospective chart review of adult patients with early-stage (T1-3; N0; M0) HR+/ ERBB2- BC who underwent genomic risk assessment of recurrence using the Oncotype DX (Exact Sciences) 21-genes assay, between January 2015 and December 2020. Clinicopathologic features were collected to assess the clinical recurrence risk. A low clinical risk score (CRS) was defined as a tumor size ≤ 3 cm in diameter with histologic grade 1, or ≤ 2 cm with grade 2 or ≤ 1 cm with grade 3. A composite risk score of distant recurrent (RRS), derived from a COX model using data from the SOFT and TEXT trials ( https://rconnect.dfci.harvard.edu/CompositeRiskSTEPP/ ), was also computed for 374 patients for whom clinical data was available. RRS > 1.42 was defined as high. High genomic risk of recurrence was defined as a score (GRS) ≥25. The data was collected under IRB approval. Results: A total of 517 patients with early-stage disease were referred for genomic testing, and clinical data was available for 501 of them. Median age was 69 years (IQR=13), median tumor size 1.03 cm (IQR=0.9), and grade 2 histology (57.49%) was the most common. Results of recurrence risk, using the 3 prognostication methods, are summarized in Table. Within patients with low CRS (n=349), 9.17% had a high GRS, compared to 8.93% in patients with low RRS (n=280). In patients with grade 1 histology (n=130), 3.85% had a high GRS and 68.46% had tumors > 1cm, of whom only 4.49% had a high GRS. Tumor size > 1cm did not associate with a high GRS (Fisher’s Exact test; P=1.00). Conclusions: In patients with early HR+/ ERBB2- BC, <10% of patients with low clinical risk, and <5% of patients with grade 1 tumors, had a high genomic recurrence risk, respectively. Given current NCCN recommendation for testing, our findings raise the question of whether genomic testing for patients with grade 1 tumors can be safely omitted, irrespective of size, and call for a better understanding of the need for routine genomic testing in patients with low grade/low clinical risk of recurrence. [Table: see text]

Very Late Recurrence in Germ Cell Tumor of the Testis: Lessons and Implications

Background. Very late recurrence (LR), i.e., >5 years after initial presentation, occurs in about 1% of patients with germ cell tumors of the testis (TGCT) and is associated with poor prognosis. Methods. We retrospectively reviewed the records of patients at the M. D. Anderson Cancer Center who developed LR > 5 years after their initial diagnosis of TGCT. Results. We identified 25 patients who developed LR between July 2007 and August 2020. The median age at the time of LR was 46 years (range, 29−61). Pathology of LR: somatic transformation to carcinoma or sarcoma—11, nonseminoma with yolk sac tumor or teratoma—11, nonseminoma without yolk sac tumor or teratoma—2, not available—1. With a median follow-up of 3.5 years, 68% of patients are alive 3 years after LR. Patients with prior post-chemotherapy consolidation surgery do not have statistically significant longer survival compared to patients who did not receive post-chemotherapy consolidation surgery, 83.3% vs. 60.8% at 3 years, respectively, p = 0.50. Conclusions. Patients with LR > 5 years tend to harbor nonseminoma (with yolk sac tumor and or teratoma). Among these patients, a majority who did not undergo surgery to remove residual disease after chemotherapy developed somatic transformation and succumbed to their LR.

Isolated Erythrocytosis Associated With 3 Novel Missense Mutations in the EGLN1 Gene

Hypoxia-inducible factor-1 (HIF-1) is a key regulator of erythropoiesis. In this article, we report 3 novel mutations, P378S, A385T, and G206C, on the EGLN1 gene encoding the negative HIF-1α regulator prolyl hydroxylase domain-2 (PHD2) in 3 patients with isolated erythrocytosis. These mutations impair PHD2 protein stability and partially reduce PHD2 activity, leading to increased HIF-1α protein levels in cultured cells.

Surgery school-who, what, when, and how: results of a national survey of multidisciplinary teams delivering group preoperative education

Background

Group education is increasing in popularity as a means of preparing patients for surgery. In recent years, these ‘surgery schools’ have evolved from primarily informing patients of what to expect before and after surgery, to providing support and encouragement for patients to ‘prehabilitate’ prior to surgery, through improving physical fitness, nutrition and emotional wellbeing.

Method

A survey aimed at clinicians delivering surgery schools was employed to capture a national overview of activity to establish research and practice priorities in this area. The survey was circulated online via the Enhanced Recovery after Surgery UK Society and the Centre for Perioperative Care mailing lists as well as social media.

Results

There were 80 responses describing 28 active and 4 planned surgery schools across the UK and Ireland. Schools were designed and delivered by multidisciplinary teams, contained broadly similar content and were well attended. Most were funded by the National Health Service. The majority included aspects of prehabilitation most commonly the importance of physical fitness. Seventy five percent of teams collected patient outcome data, but less than half collected data to establish the clinical effectiveness of the school. Few describe explicit inclusion of evidence-based behavior change techniques, but collaboration and partnerships with community teams, gyms and local charities were considered important in supporting patients to make changes in health behaviors prior to surgery.

Conclusion

It is recommended that teams work with patients when designing surgery schools and use evidence-based behavior change frameworks and techniques to inform their content. There is a need for high-quality research studies to determine the clinical effectiveness of this type of education intervention.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13741-021-00188-2.

Very late recurrence in germ cell tumor of the testis: Lessons and implications

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Background: Up to 30% of patients with germ cell tumor of the testis (TGCT) develop recurrent disease after initial treatment. The majority of recurrences occur in the first 2 years after treatment. Very late recurrence (LR), i.e. > 5 years after initial presentation, occurs in about 1% of patients with TGCT and is associated with poor prognosis. Current guideline does not require follow-up after 5 years to detect LR, except in those presenting with metastatic NSGCT. Methods: We retrospectively reviewed the records of patients from the Genitourinary Medical Oncology clinic at the M. D. Anderson Cancer Center, who developed recurrent disease > 5 years after their initial diagnosis of TGCT. Specifically, we examined the pathology and location of their primary and recurrent tumors, treatments rendered (e.g., surgery, radiotherapy, chemotherapy), and overall survival after LR. Overall survival from the time of LR was estimated using Kaplan-Meier estimates and compared for patient subgroups with log rank tests. Fisher’s exact test was used to compare proportions in patient subgroups. Results: We identified 25 patients who developed LR between July 2007 and August 2020. Age at time of LR: median 46 years (range, 29-61); time of late LR: median 16.1 years (range, 6.8-33.1 years) after diagnosis. Stage at time of diagnosis: I – 5, II-IIIA – 13, IIIB-C – 7. Pathology of primary: nonseminoma with yolk sac tumor or teratoma – 15, nonseminoma without yolk sac tumor or teratoma – 1, not available – 9. Pathology of LR: somatic transformation to carcinoma – 9, somatic transformation to sarcoma – 2, nonseminoma with yolk sac tumor or teratoma – 10, nonseminoma without yolk sac tumor or teratoma – 2, not available – 2. Overall, 5 patients (20%) had LR in retroperitoneum alone, 6 patients (24%) had non-retroperitoneal nodal or pulmonary metastases, and 14 patients (56%) had non-pulmonary visceral metastases. Nine patients (36%) are deceased, ten patients (40%) are alive without evidence of disease (NED), and 6 patients are alive with disease (24%). With a median follow-up of 42 months, 68% of patients are alive 3 years after LR. Patients with prior post-chemotherapy consolidation surgery have longer survival, 80% vs. 53% at 3 years, respectively (p = 0.01). Additionally, at their last follow-up 9/12 vs. 1/13 patients were NED with vs. without prior post-chemotherapy consolidation surgery, respectively (p = 0.001). Conclusions: Patients with LR > 5 years after initial presentation tend to harbor nonseminoma (with yolk sac tumor and or teratoma). Among these patients, a majority who did not undergo surgery to remove residual disease after chemotherapy developed somatic transformation and succumbed to their LR. Further investigation into rates of LR among all patients may be warranted given the poor survival after LR.

A Prospective Cohort Study of Neural Progenitor Cell-Sparing Radiation Therapy Plus Temozolomide for Newly Diagnosed Patients With Glioblastoma

BACKGROUND

In treating glioblastoma, irradiation of the neural progenitor cell (NPC) niches is controversial. Lower hippocampal doses may limit neurocognitive toxicity, but higher doses to the subventricular zones (SVZ) may improve survival.

OBJECTIVE

To prospectively evaluate the impact of limiting radiation dose to the NPC niches on tumor progression, survival, and cognition in patients with glioblastoma.

METHODS

Patients with glioblastoma received resection followed by standard chemoradiation. Radiation dose to the NPC niches, including the bilateral hippocampi and SVZ, was minimized without compromising tumor coverage. The primary outcome was tumor progression in the spared NPC niches. Follow-up magnetic resonance imaging was obtained bimonthly. Neurocognitive testing was performed before treatment and at 6- and 12-mo follow-up. Cox regression evaluated predictors of overall and progression-free survival. Linear regression evaluated predictors of neurocognitive decline.

RESULTS

A total of 30 patients enrolled prospectively. The median age was 58 yr. Median mean doses to the hippocampi and SVZ were 49.1 and 41.8 gray (Gy) ipsilaterally, and 16.5 and 19.9 Gy contralaterally. Median times to death and tumor progression were 16.0 and 7.6 mo, and were not significantly different compared to a matched historical control. No patients experienced tumor progression in the spared NPC-containing regions. Overall survival was associated with neurocognitive function (P ≤ .03) but not dose to the NPC niches. Higher doses to the hippocampi and SVZ predicted greater decline in verbal memory (P ≤ .01).

CONCLUSION

In treating glioblastoma, limiting dose to the NPC niches may reduce cognitive toxicity while maintaining clinical outcomes. Further studies are needed to confirm these results.

Glioblastoma and Increased Survival with Longer Chemotherapy Duration

Introduction The five-year survival rate for patients with glioblastoma (GBM) is low at approximately 4.7%. Radiotherapy plus concomitant and adjuvant temozolomide (TMZ) remains the standard of care. The optimal duration of therapy with TMZ is unknown. This study sought to evaluate the survival benefit of two years of treatment. Methods This was a retrospective chart review of all patients diagnosed with GBM and treated with TMZ for up to two years between January 1, 2002 and December 31, 2011. The Kaplan-Meier method with log-rank test was used to estimate the progression-free survival (PFS) and the overall survival (OS). The results were compared to historical controls and data from previous clinical trials of patients treated up to one year. Results Data from 56 patients with confirmed GBM were evaluated. The OS probability was 54% (SE = 0.068) at one year, 28.3% (SE = 0.064) at two years, 17.8% (SE = 0.059) at three years, and 4% (SE = 0.041) at five years. Seven patients (12.5%) were treated with TMZ for two years. Their median time-to-progression was 28 months (95% CI = 5.0 - 28.0), and they had an increased survival probability at three years compared to other patients (log-rank test χ2 (1, N = 56) = 19.2, p < 0.0001). Conclusions There may be an advantage for a longer duration of TMZ therapy among patients with GBM, but the sample size was too small for generalization. A multicenter prospective study is needed to dentify optimal duration of TMZ therapy.

Glioblastoma and Increased Survival with Longer Chemotherapy Duration

INTRODUCTION

The five-year survival rate for patients with glioblastoma (GBM) is low at approximately 4.7%. Radiotherapy plus concomitant and adjuvant temozolomide (TMZ) remains the standard of care. The optimal duration of therapy with TMZ is unknown. This study sought to evaluate the survival benefit of two years of treatment.

METHODS

This was a retrospective chart review of all patients diagnosed with GBM and treated with TMZ for up to two years between January 1, 2002 and December 31, 2011. The Kaplan-Meier method with log-rank test was used to estimate the progression-free survival (PFS) and the overall survival (OS). The results were compared to historical controls and data from previous clinical trials of patients treated up to one year.

RESULTS

Data from 56 patients with confirmed GBM were evaluated. The OS probability was 54% (SE = 0.068) at one year, 28.3% (SE = 0.064) at two years, 17.8% (SE = 0.059) at three years, and 4% (SE = 0.041) at five years. Seven patients (12.5%) were treated with TMZ for two years. Their median time-to-progression was 28 months (95% CI = 5.0 - 28.0), and they had an increased survival probability at three years compared to other patients (log-rank test χ² (1, N = 56) = 19.2, p < 0.0001).

CONCLUSIONS

There may be an advantage for a longer duration of TMZ therapy among patients with GBM, but the sample size was too small for generalization. A multicenter prospective study is needed to identify optimal duration of TMZ therapy.

Comparison of treatment planning approaches for spatially fractionated irradiation of deep tumors

Purpose

The purpose of this work was to compare the dosimetry and delivery times of 3D‐conformal (3DCRT)‐, volumetric modulated arc therapy (VMAT)‐, and tomotherapy‐based approaches for spatially fractionated radiation therapy for deep tumor targets.

Methods

Two virtual GRID phantoms were created consisting of 7 “target” cylinders (1‐cm diameter) aligned longitudinally along the tumor in a honey‐comb pattern, mimicking a conventional GRID block, with 2‐cm center‐to‐center spacing (GRID_2 cm) and 3‐cm center‐to‐center spacing (GRID_3 cm), all contained within a larger cylinder (8 and 10 cm in diameter for the GRID_2 cm and GRID_3 cm, respectively). In a single patient, a GRID_3 cm structure was created within the gross tumor volume (GTV). Tomotherapy, VMAT (6 MV + 6 MV‐flattening‐filter‐free) and multi‐leaf collimator segment 3DCRT (6 MV) plans were created using commercially available software. Two tomotherapy plans were created with field widths (TOMO_2.5 cm) 2.5 cm and (TOMO_5 cm) 5 cm. Prescriptions for all plans were set to deliver a mean dose of 15 Gy to the GRID targets in one fraction. The mean dose to the GRID target and the heterogeneity of the dose distribution (peak‐to‐valley and peak‐to‐edge dose ratios) inside the GRID target were obtained. The volume of normal tissue receiving 7.5 Gy was determined.

Results

The peak‐to‐valley ratios for GRID_2 cm/GRID_3 cm/Patient were 2.1/2.3/2.8, 1.7/1.5/2.8, 1.7/1.9/2.4, and 1.8/2.0/2.8 for the 3DCRT, VMAT, TOMO_5 cm, and TOMO_2.5 cm plans, respectively. The peak‐to‐edge ratios for GRID_2 cm/GRID_3 cm/Patient were 2.8/3.2/5.4, 2.1/1.8/5.4, 2.0/2.2/3.9, 2.1/2.7/5.2 and for the 3DCRT, VMAT, TOMO_5 cm, and TOMO_2.5 cm plans, respectively. The volume of normal tissue receiving 7.5 Gy was lowest in the TOMO_2.5 cm plan (GRID_2 cm/GRID_3 cm/Patient = 54 cm³/19 cm³/10 cm³). The VMAT plans had the lowest delivery times (GRID_2 cm/GRID_3 cm/Patient = 17 min/8 min/9 min).

Conclusion

Our results present, for the first time, preliminary evidence comparing IMRT‐GRID approaches which result in high‐dose “islands” within a target, mimicking what is achieved with a conventional GRID block but without high‐dose “tail” regions outside of the target. These approaches differ modestly in their ability to achieve high peak‐to‐edge ratios and also differ in delivery times.

Radio-morphology: Parametric shape-based features in radiotherapy

PURPOSE

In radiotherapy, it is necessary to characterize dose over the patient anatomy to target areas and organs at risk. Current tools provide methods to describe dose in terms of percentage of volume and magnitude of dose, but are limited by assumptions of anatomical homogeneity within a region of interest (ROI) and provide a non-spatially aware description of dose. A practice termed radio-morphology is proposed as a method to apply anatomical knowledge to parametrically derive new shapes and substructures from a normalized set of anatomy, ensuring consistently identifiable spatially aware features of the dose across a patient set.

METHODS

Radio-morphologic (RM) features are derived from a three-step procedure: anatomy normalization, shape transformation, and dose calculation. Predefined ROI's are mapped to a common anatomy, a series of geometric transformations are applied to create new structures, and dose is overlaid to the new images to extract dosimetric features; this feature computation pipeline characterizes patient treatment with greater anatomic specificity than current methods.

RESULTS

Examples of applications of this framework to derive structures include concentric shells based around expansions and contractions of the parotid glands, separation of the esophagus into slices along the z-axis, and creating radial sectors to approximate neurovascular bundles surrounding the prostate. Compared to organ-level dose-volume histograms (DVHs), using derived RM structures permits a greater level of control over the shapes and anatomical regions that are studied and ensures that all new structures are consistently identified. Using machine learning methods, these derived dose features can help uncover dose dependencies of inter- and intra-organ regions. Voxel-based and shape-based analysis of the parotid and submandibular glands identified regions that were predictive of the development of high-grade xerostomia (CTCAE grade 2 or greater) at 3-6 months post treatment.

CONCLUSIONS

Radio-morphology is a valuable data mining tool that approaches radiotherapy data in a new way, improving the study of radiotherapy to potentially improve prognostic and predictive accuracy. Further applications of this methodology include the use of parametrically derived sub-volumes to drive radiotherapy treatment planning.

Antibacterial activity of disulfiram and its metabolites

AIMS

Disulfiram (Antabuse™) and its metabolites formed in vivo were evaluated as antibacterial agents against thirty species of Gram-positive and Gram-negative bacteria. The synergistic potential of disulfiram (DSF) and metabolite diethyldithiocarbamate (DDTC) with approved antibiotics were also compared by isobologram (checkerboard) analysis.

METHODS AND RESULTS

Standard microdilution susceptibility testing showed that most DSF metabolites did not possess appreciable antibacterial activity except for DDTC in Bacillus anthracis. Checkerboard studies revealed similarities between the combination drug effects of DSF and DDTC with standard antibiotics.

CONCLUSIONS

It was concluded from the susceptibility data that the metabolites would not extend the antibacterial spectrum of DSF in vivo. The data also suggest that the DDTC by-product of DSF metabolism potentiates the antibacterial activity of DSF as both a standalone and combination agent.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study provides a greater understanding of the antibacterial effects of Antabuse and its metabolites. This research also demonstrates the potential application of DSF as an antibiotic adjuvant for the treatment of resistant staph infections.

Practice Patterns and Impact of Postchemotherapy Retroperitoneal Lymph Node Dissection on Testicular Cancer Outcomes

Background

Owing to surgical complexity and controversy regarding indications, there are wide practice variations in the use of postchemotherapy retroperitoneal lymph node dissection (PC-RPLND).

Objective

To evaluate patterns of PC-RPLND use in the USA and evaluate the association between PC-RPLND and survival in advanced nonseminomatous germ cell tumors (NSGCTs).

Design setting and participants

A retrospective, observational study using National Cancer Data Base (NCDB) data from 2004-2014 for 5062 men diagnosed with stage II/III NSGCT.

Outcome measurements and statistical analysis

In a comparative analysis based on receipt of PC-RPLND, the primary outcome of interest was factors associated with omission of PC-RPLND as explored via logistic regression. As a secondary outcome, we evaluated the association between PC-RPLND and overall survival (OS) via multivariable Cox regression and propensity score matching (PSM).

Results and limitations

Patients undergoing PC-RPLND were more likely to be younger, white, privately insured, and reside in more educated/wealthier regions (p < 0.001). Insurance status was independently associated with receipt of PC-RPLND; compared to patients with private insurance, those without insurance were significantly less likely to receive PC-RPLND (odds ratio 0.49; p < 0.001). After multivariate adjustment, age, comorbidity, non-private insurance, distance from hospital, clinical stage, and risk group were independently associated with all-cause mortality. In addition, omission of PC-RPLND remained associated with all-cause mortality (hazard ratio 1.98; p < 0.001). After PSM, the 5-yr OS was significantly lower among those not undergoing PC-RPLND (72% vs 77%; p = 0.007).

Conclusions

PC-RPLND represents a critical part of the multidisciplinary management of NSGCT. Patients with non-private insurance are less likely to undergo PC-RPLND, and omission of PC-RPLND is associated with lower OS.

Patient summary

We evaluated the practice patterns for advanced testicular cancer management and found that patients who did not undergo a postchemotherapy retroperitoneal lymph node dissection were more likely to have worse survival outcomes. Patients with unfavorable insurance were less likely to receive this surgical treatment.

Improving prediction of surgical resectability over current staging guidelines in patients with pancreatic cancer who receive stereotactic body radiation therapy

Purpose

For patients with localized pancreatic cancer (PC) with vascular involvement, prediction of resectability is critical to define optimal treatment. However, the current definitions of borderline resectable (BR) and locally advanced (LA) disease leave considerable heterogeneity in outcomes within these classifications. Moreover, factors beyond vascular involvement likely affect the ability to undergo resection. Herein, we share our experience developing a model that incorporates detailed radiologic, patient, and treatment factors to predict surgical resectability in patients with BR and LA PC who undergo stereotactic body radiation therapy (SBRT).

Methods and materials

Patients with BR or LA PC who were treated with SBRT between 2010 and 2016 were included. The primary endpoint was margin negative resection, and predictors included age, sex, race, treatment year, performance status, initial staging, tumor volume and location, baseline and pre-SBRT carbohydrate antigen 19-9 levels, chemotherapy regimen and duration, and radiation dose. In addition, we characterized the relationship between tumors and key arteries (superior mesenteric, celiac, and common hepatic arteries), using overlap volume histograms derived from computed tomography data. A classification and regression tree was built, and leave-one-out cross-validation was performed. Prediction of surgical resection was compared between our model and staging in accordance with the National Comprehensive Care Network guidelines using McNemar's test.

Results

A total of 191 patients were identified (128 patients with LA and 63 with BR), of which 87 patients (46%) underwent margin negative resection. The median total dose was 33 Gy. Predictors included the chemotherapy regimen, amount of arterial involvement, and age. Importantly, radiation dose that covers 95% of gross tumor volume (GTV D95), was a key predictor of resectability in certain subpopulations, and the model showed improved accuracy in the prediction of margin negative resection compared with National Comprehensive Care Network guideline staging (75% vs 63%; P < .05).

Conclusions

We demonstrate the ability to improve prediction of surgical resectabiliy beyond the current staging guidelines, which highlights the value of assessing vascular involvement in a continuous manner. In addition, we show an association between radiation dose and resectability, which suggests the potential importance of radiation to allow for resection in certain populations. External data are needed for validation and to increase the robustness of the model.

Evaluation of classification and regression tree (CART) model in weight loss prediction following head and neck cancer radiation therapy

OBJECTIVE

We explore whether a knowledge-discovery approach building a Classification and Regression Tree (CART) prediction model for weight loss (WL) in head and neck cancer (HNC) patients treated with radiation therapy (RT) is feasible.

METHODS AND MATERIALS

HNC patients from 2007 to 2015 were identified from a prospectively collected database Oncospace. Two prediction models at different time points were developed to predict weight loss ≥5 kg at 3 months post-RT by CART algorithm: (1) during RT planning using patient demographic, delineated dose data, planning target volume-organs at risk shape relationships data and (2) at the end of treatment (EOT) using additional on-treatment toxicities and quality of life data.

RESULTS

Among 391 patients identified, WL predictors during RT planning were International Classification of Diseases diagnosis; dose to masticatory and superior constrictor muscles, larynx, and parotid; and age. At EOT, patient-reported oral intake, diagnosis, N stage, nausea, pain, dose to larynx, parotid, and low-dose planning target volume-larynx distance were significant predictive factors. The area under the curve during RT and EOT was 0.773 and 0.821, respectively.

CONCLUSIONS

We demonstrate the feasibility and potential value of an informatics infrastructure that has facilitated insight into the prediction of WL using the CART algorithm. The prediction accuracy significantly improved with the inclusion of additional treatment-related data and has the potential to be leveraged as a strategy to develop a learning health system.

Dose to mass for evaluation and optimization of lung cancer radiation therapy

PURPOSE

To evaluate potential organ at risk dose-sparing by using dose-mass-histogram (DMH) objective functions compared with dose-volume-histogram (DVH) objective functions.

METHODS

Treatment plans were retrospectively optimized for 10 locally advanced non-small cell lung cancer patients based on DVH and DMH objectives. DMH-objectives were the same as DVH objectives, but with mass replacing volume. Plans were normalized to dose to 95% of the PTV volume (PTV-D95v) or mass (PTV-D95m). For a given optimized dose, DVH and DMH were intercompared to ascertain dose-to-volume vs. dose-to-mass differences. Additionally, the optimized doses were intercompared using DVH and DMH metrics to ascertain differences in optimized plans. Mean dose to volume, D_v‾, mean dose to mass, D_M‾, and fluence maps were intercompared.

RESULTS

For a given dose distribution, DVH and DMH differ by >5% in heterogeneous structures. In homogeneous structures including heart and spinal cord, DVH and DMH are nearly equivalent. At fixed PTV-D95v, DMH-optimization did not significantly reduce dose to OARs but reduced PTV-D_v‾ by 0.20±0.2Gy (p=0.02) and PTV-D_M‾ by 0.23±0.3Gy (p=0.02). Plans normalized to PTV-D95m also result in minor PTV dose reductions and esophageal dose sparing (D_v‾ reduced 0.45±0.5Gy, p=0.02 and D_M‾ reduced 0.44±0.5Gy, p=0.02) compared to DVH-optimized plans. Optimized fluence map comparisons indicate that DMH optimization reduces dose in the periphery of lung PTVs.

CONCLUSIONS

DVH- and DMH-dose indices differ by >5% in lung and lung target volumes for fixed dose distributions, but optimizing DMH did not reduce dose to OARs. The primary difference observed in DVH- and DMH-optimized plans were variations in fluence to the periphery of lung target PTVs, where low density lung surrounds tumor.

Thyroid storm and warm autoimmune hemolytic anemia

Graves' disease is often associated with other autoimmune disorders, including rare associations with autoimmune hemolytic anemia (AIHA). We describe a unique presentation of thyroid storm and warm AIHA diagnosed concurrently in a young female with hyperthyroidism. The patient presented with nausea, vomiting, diarrhea and altered mental status. Laboratory studies revealed hemoglobin 3.9g/dL, platelets 171×10⁹L^-1, haptoglobin <5mg/dL, reticulocytosis, and positive direct antiglobulin test (IgG, C3d, warm). Additional workup revealed serum thyroid stimulating hormone (TSH) <0.01μIU/mL and serum free-T4 (FT4) level 7.8ng/dL. Our patient was diagnosed with concurrent thyroid storm and warm AIHA. She was started on glucocorticoids to treat both warm AIHA and thyroid storm, as well as antithyroid medications, propranolol and folic acid. Due to profound anemia and hemodynamic instability, the patient was transfused two units of uncrossmatched packed red blood cells slowly and tolerated this well. She was discharged on methimazole as well as a prolonged prednisone taper, and achieved complete resolution of the thyrotoxicosis and anemia at one month. Hyperthyroidism can affect all three blood cell lineages of the hematopoietic system. Anemia can be seen in 10-20% of patients with thyrotoxicosis. Several autoimmune processes can lead to anemia in Graves' disease, including pernicious anemia, celiac disease, and warm AIHA. This case illustrates a rarely described presentation of a patient with Graves' disease presenting with concurrent thyroid storm and warm AIHA.

Automated electrotransformation of Escherichia coli on a digital microfluidic platform using bioactivated magnetic beads

This paper reports on the use of a digital microfluidic platform to perform multiplex automated genetic engineering (MAGE) cycles on droplets containing Escherichia coli cells. Bioactivated magnetic beads were employed for cell binding, washing, and media exchange in the preparation of electrocompetent cells in the electrowetting-on-dieletric (EWoD) platform. On-cartridge electroporation was used to deliver oligonucleotides into the cells. In addition to the optimization of a magnetic bead-based benchtop protocol for generating and transforming electrocompetent E. coli cells, we report on the implementation of this protocol in a fully automated digital microfluidic platform. Bead-based media exchange and electroporation pulse conditions were optimized on benchtop for transformation frequency to provide initial parameters for microfluidic device trials. Benchtop experiments comparing electrotransformation of free and bead-bound cells are presented. Our results suggest that dielectric shielding intrinsic to bead-bound cells significantly reduces electroporation field exposure efficiency. However, high transformation frequency can be maintained in the presence of magnetic beads through the application of more intense electroporation pulses. As a proof of concept, MAGE cycles were successfully performed on a commercial EWoD cartridge using variations of the optimal magnetic bead-based preparation procedure and pulse conditions determined by the benchtop results. Transformation frequencies up to 22% were achieved on benchtop; this frequency was matched within 1% (21%) by MAGE cycles on the microfluidic device. However, typical frequencies on the device remain lower, averaging 9% with a standard deviation of 9%. The presented results demonstrate the potential of digital microfluidics to perform complex and automated genetic engineering protocols.

Homo- and Co-Polycarbonates and Blends Derived from Diphenolic Acid

The properties of materials derived from diphenolic acid (4-(bis(hydroxyphenyl))pentanoic acid, DPA), such as polycarbonate homo- and co-polymers (with bisphenol A, BPA), have been determined. The influence of copolymer composition on the thermal properties of these materials has been determined. Blends of polycarbonates from BPA and from DPA appear to be compatible.

A prospective study evaluating stereotactic body radiation therapy in unresectable, recurrent, or residual pancreatic adenocarcinoma

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Background: The purpose of this prospective, non-randomized phase II single-institution study was to evaluate if local control can be achieved with reasonable acute and late GI toxicity using fractionated SBRT in patients with unresectable, recurrent, or residual locally advanced pancreatic cancer (LAPC). Methods: A total of 24 patients with LAPC were enrolled from June 2013 to August 2014. Eligibility required stability after induction chemotherapy or residual disease or local failure after surgery. Induction chemotherapy regimens consisted of: (1) gemcitabine alone (8%); (2) gemcitabine-based regimens (17%); (3) FOLFIRINOX-based regimens (63%); or (4) combination regimens (13%). Chemotherapy was discontinued one week prior to SBRT. Patients received a median cumulative dose of 33 Gy in 5 fractions (5-6.6 Gy/fraction). Patients were permitted to resume chemotherapy one week post-SBRT. Toxicity was assessed using the NCI CTCAE version 4.0. Results: Of the 24 patients, 58% were male and 50% had tumors in the head of the pancreas. Median age at diagnosis was 66.8 years, and median follow-up from the date of diagnosis was 11.9 months (range, 7.4-29.7 months). There have not been any acute or late grade ≥ 2 gastritis, enteritis, fistula, or ulcer toxicities (primary endpoint). Median OS has not yet been reached, median LPFS was 19.3 months (95% CI, 12.3-14.8), median DMFS was 13.6 months (95% CI, 9.2-17.9) and median PFS was 13.6 months (95% CI, 13.5-25.2). Plasma CA 19-9 level was non-significantly reduced after SBRT, displaying a -9.15 average percent change from baseline (median time after SBRT, 1.2 months). FFLP at 1 year was 83.9%. Eight (33%) patients underwent successful surgery following SBRT, with rates of both margin- and node-negative resection being 75%. Conclusions: Chemotherapy followed by fractionated SBRT results in favorable local control and survival with minimal acute and late GI toxicity. A notable proportion of patients initially deemed unresectable underwent successful resection. This study suggests that SBRT can be safely given following more aggressive multiagent chemotherapy in patients with LAPC. Clinical trial information: NCT01781728.

Disruption of the cytochrome P-450 1B1 gene exacerbates renal dysfunction and damage associated with angiotensin II-induced hypertension in female mice

Recently, we demonstrated in female mice that protection against ANG II-induced hypertension and associated cardiovascular changes depend on cytochrome P-450 (CYP)1B1. The present study was conducted to determine if Cyp1b1 gene disruption ameliorates renal dysfunction and organ damage associated with ANG II-induced hypertension in female mice. ANG II (700 ng·kg(-1)·min(-1)) infused by miniosmotic pumps for 2 wk in female Cyp1b1(+/+) mice did not alter water consumption, urine output, Na(+) excretion, osmolality, or protein excretion. However, in Cyp1b1(-/-) mice, ANG II infusion significantly increased (P < 0.05) water intake (5.50 ± 0.42 ml/24 h with vehicle vs. 8.80 ± 0.60 ml/24 h with ANG II), urine output (1.44 ± 0.37 ml/24 h with vehicle vs. 4.30 ± 0.37 ml/24 h with ANG II), and urinary Na(+) excretion (0.031 ± 0.016 mmol/24 h with vehicle vs. 0.099 ± 0.010 mmol/24 h with ANG II), decreased osmolality (2,630 ± 79 mosM/kg with vehicle vs. 1,280 ± 205 mosM/kg with ANG II), and caused proteinuria (2.60 ± 0.30 mg/24 h with vehicle vs. 6.96 ± 0.55 mg/24 h with ANG II). Infusion of ANG II caused renal fibrosis, as indicated by an accumulation of renal interstitial α-smooth muscle actin, collagen, and transforming growth factor-β in Cyp1b1(-/-) but not Cyp1b1(+/+) mice. ANG II also increased renal production of ROS and urinary excretion of thiobarburic acid-reactive substances and reduced the activity of antioxidants and urinary excretion of nitrite/nitrate and the 17β-estradiol metabolite 2-methoxyestradiol in Cyp1b1(-/-) but not Cyp1b1(+/+) mice. These data suggest that Cyp1b1 plays a critical role in female mice in protecting against renal dysfunction and end-organ damage associated with ANG II-induced hypertension, in preventing oxidative stress, and in increasing activity of antioxidant systems, most likely via generation of 2-methoxyestradiol from 17β-estradiol.

Multiple anatomy optimization of accumulated dose

PURPOSE

To investigate the potential advantages of multiple anatomy optimization (MAO) for lung cancer radiation therapy compared to the internal target volume (ITV) approach.

METHODS

MAO aims to optimize a single fluence to be delivered under free-breathing conditions such that the accumulated dose meets the plan objectives, where accumulated dose is defined as the sum of deformably mapped doses computed on each phase of a single four dimensional computed tomography (4DCT) dataset. Phantom and patient simulation studies were carried out to investigate potential advantages of MAO compared to ITV planning. Through simulated delivery of the ITV- and MAO-plans, target dose variations were also investigated.

RESULTS

By optimizing the accumulated dose, MAO shows the potential to ensure dose to the moving target meets plan objectives while simultaneously reducing dose to organs at risk (OARs) compared with ITV planning. While consistently superior to the ITV approach, MAO resulted in equivalent OAR dosimetry at planning objective dose levels to within 2% volume in 14/30 plans and to within 3% volume in 19/30 plans for each lung V20, esophagus V25, and heart V30. Despite large variations in per-fraction respiratory phase weights in simulated deliveries at high dose rates (e.g., treating 4/10 phases during single fraction beams) the cumulative clinical target volume (CTV) dose after 30 fractions and per-fraction dose were constant independent of planning technique. In one case considered, however, per-phase CTV dose varied from 74% to 117% of prescription implying the level of ITV-dose heterogeneity may not be appropriate with conventional, free-breathing delivery.

CONCLUSIONS

MAO incorporates 4DCT information in an optimized dose distribution and can achieve a superior plan in terms of accumulated dose to the moving target and OAR sparing compared to ITV-plans. An appropriate level of dose heterogeneity in MAO plans must be further investigated.

Conversations in cardiology: bridging antiplatelet therapy before surgery

Bridging for antiplatelet therapy remains a subject of debate with data favoring GP blockers but at a risk of bleeding. This Conversation in Cardiology addresses a key and often asked question about use of alternatives to P2Y12 agents in patients requiring surgery within 6 months after drug eluting stent implantation.

Clinical deployment of automatic treatment planning for pancreas SBRT patients

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Background: To clinically utilize an SQL relational database of prior treated patients to generate objectives for future treatment plans. A database approach allows for more rapid planning by starting with a better initial solution and improves safety by providing good known achievable dose values for the initial optimization. The use of a database allows for trending of dose, structure and toxicity data. Methods: A database of fifty-three patients from three institutions is populated with dose and structure data via an automatic script within the treatment planning system. For each new patient, overlap volume histograms (OVHs) are generated to describe the relationship between targets and critical structures. To aid in database consistency, a renaming interface is used which maps known alternative structure names to common names in the database. To ensure all required structures are present, the user is prompted with the names of missing structures. This interface allows selection of machine, energy and commonly used beam sets. The database is queried for all prior patients with the same or closer relationship between the target and each critical structure. The dose objectives reported are the lowest achievable dose from all patients as difficult or harder to plan as determined by OVH. Queried dose objectives are automatically loaded into the treatment planning system and optimized. A protocol quality tool is developed to quickly assess how well plans adhere to specified protocols. Results: Twenty-seven SBRT patients have been planned and clinically approved using the automatic planning tool and future patients continue to be added to the database. OVH computation required approximately 2 minutes, while typical plan optimization required 2.5 minutes. If auto-planned patients require even one fewer optimization to achieve an acceptable plan, total planning time is reduced. Safety is improved by reducing the number of protocol violations from 35% to 6% for one objective. Conclusions: Automatic treatment planning allows for rapid planning while reducing normal tissue dose to known achievable values. The continued addition of patients to the database allows for improvement of the automatically selected planning objectives.

Mapping patterns of local recurrence after pancreaticoduodenectomy for pancreatic adenocarcinoma: a new approach to adjuvant radiation field design

PURPOSE

To generate a map of local recurrences after pancreaticoduodenectomy (PD) for patients with resectable pancreatic ductal adenocarcinoma (PDA) and to model an adjuvant radiation therapy planning treatment volume (PTV) that encompasses a majority of local recurrences.

METHODS AND MATERIALS

Consecutive patients with resectable PDA undergoing PD and 1 or more computed tomography (CT) scans more than 60 days after PD at our institution were reviewed. Patients were divided into 3 groups: no adjuvant treatment (NA), chemotherapy alone (CTA), or chemoradiation (CRT). Cross-sectional scans were centrally reviewed, and local recurrences were plotted to scale with respect to the celiac axis (CA), superior mesenteric artery (SMA), and renal veins on 1 CT scan of a template post-PD patient. An adjuvant clinical treatment volume comprising 90% of local failures based on standard expansions of the CA and SMA was created and simulated on 3 post-PD CT scans to assess the feasibility of this planning approach.

RESULTS

Of the 202 patients in the study, 40 (20%), 34 (17%), and 128 (63%) received NA, CTA, and CRT adjuvant therapy, respectively. The rate of margin-positive resections was greater in CRT patients than in CTA patients (28% vs 9%, P=.023). Local recurrence occurred in 90 of the 202 patients overall (45%) and in 19 (48%), 22 (65%), and 49 (38%) in the NA, CTA, and CRT groups, respectively. Ninety percent of recurrences were within a 3.0-cm right-lateral, 2.0-cm left-lateral, 1.5-cm anterior, 1.0-cm posterior, 1.0-cm superior, and 2.0-cm inferior expansion of the combined CA and SMA contours. Three simulated radiation treatment plans using these expansions with adjustments to avoid nearby structures were created to demonstrate the use of this treatment volume.

CONCLUSIONS

Modified PTVs targeting high-risk areas may improve local control while minimizing toxicities, allowing dose escalation with intensity-modulated or stereotactic body radiation therapy.

Glioblastoma and increased survival with longer chemotherapy duration

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Background: The 5-year survival for patients (pts) with glioblastoma (GBM) is low at approximately 3%. Radiotherapy plus concomitant and adjuvant temozolomide (TMZ) remain the standard of care. The optimal duration of therapy with TMZ is unknown, though treatment periods of 6 months (mo), 12 mo and longer have been utilized. Whether or not there is a benefit with longer treatment duration is controversial. Methods: A retrospective chart review of all pts diagnosed with GBM who were treated at a regional referral center was conducted with data obtained from their electronic medical records. These pts were treated with TMZ for up to 2 years between January 1, 2002 and December 31, 2011. Survival was calculated as the time from initial surgical diagnosis until death. The Kaplan-Meier method with log-rank test was used to estimate the progression-free survival (PFS) as well as the overall survival (OS) distribution of pts after treatment. The results were compared to historical controls and data from previous clinical trials of pts treated up to 1 year. Results: Data from 56 pts were evaluated, the majority of whom had gross total resection and had external pathology review confirming the diagnosis of GBM. The OS probability was 55.4% (SE = 0.068) at 1 year, 26.9% (SE = 0.067) at 2 years and 20.1% (SE = 0.065) at 3 years. The median PFS time in this study group was 8 mo (95% CI = 4.0 – 9.0 mo). The probability of no progression at 2 years was 8.6% (SE = 0.05). Seven pts (12.5%) were treated with TMZ for 2 years. The probability of disease progression at 2 years among these pts was 33.3% with a median time-to-progression of 20 mo (95% CI = 5.0-28.0). These patients showed an increased survival probability at 3 years compared to pts who did not receive the 2 year treatment of TMZ (log-rank test Chi-square = 12.4, p = 0.0004). Conclusions: This analysis suggests that there may be an advantage for a longer duration of TMZ therapy in pts with GBM. In this review, treatment with TMZ for 2 years was associated with an increased survival benefit. While we consider the sample size to be too small for generalization, a prospective/multicenter study with a larger sample size might better evaluate the question of duration of TMZ therapy, particularly if both clinical and basic science data are paired.

Feasibility and efficiency of automatic treatment planning for stereotactic body radiation therapy (SBRT) in pancreatic cancer patients

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Background: Overlap volume histogrmas (OVHs) allow for new plans to be generated based upon prior similar treatment plans. The purpose of this project was to clinically deploy a generic and user-friendly interface for using a database populated with OVHs for planning SBRT pancreas patients. An interface for evaluating adherence to protocol tolerances is also developed to aid in the planning process. Methods: A database of previously treated SBRT pancreas patients is used to query the organ at risk (OAR) dose from patients with similar or harder to plan OVHs. For each OAR in a new plan, the database is queried to find the lowest achievable structure dose from all previous patients with a greater than or equal overlap between the selected structure and the target structure. Queried values are then automatically loaded into the inverse planning optimizer objectives and used to generate an optimized plan. Plans are then evaluated using a protocol interface which queries relevant protocol values and displays the values in a color-coded interface. Upon plan completion the system submits the new patient data to the OVH database and stores relevant DVH metrics in the MOSAIQ database for tracking. Results: The interface has been used to successfully plan 5 SBRT patients. All planned patients met protocol requirements. Automatic plans required fewer iterations to produce an acceptable plan. The physician indicated preference to the automatically generated plans due to better adherence to protocol requirements and lower critical structure doses. Conclusions: Automatic planning can be used to generate clinical plans which reduce dose to normal tissues while achieving the dose distribution required by clinical protocols. The protocol interface allows for more rapid evaluation of plan acceptability during planning and for physician review. The system can be deployed clinically, but requires adherence by all participants to standard naming conventions for targets and OARs.

SU-F-BRCD-06: Multiple Anatomy Optimization of Accumulated Dose

PURPOSE

Multiple anatomy optimization (MAO) utilizing deformable dose accumulation on entire 4DCT data sets is implemented to overcome ambiguity between optimal dose defined on a single anatomy and optimal accumulated dose resulting from dose delivery to moving and deforming anatomy.

METHODS

Six lung cancer patients are planned using two methods of radiotherapy optimization: the internal target volume (ITV) envelope method and MAO, which simultaneously optimizes a single fluence for delivery to all 10 breathing phases such that the accumulated dose satisfies the plan objectives. Target dose is constrained to 70 Gy. The ITV-plan is optimized on a single breathing phase with the planning target volume defined as the ITV; the MAO target is the moving CTV. MAO is compared to single image ITV optimization based on the accumulated dose assuming equal monitor-units to each phase. Dose-volume differences between single image estimations and 10-image accumulation are examined.

RESULTS

Single image optimal dose distributions overestimate target V70 by 4.2%±3.1% (average, one standard deviation) and in five of six cases ipsilateral lung V20 is underestimated (1.4%±0.9%). For these five cases, MAO increases V70 by 2.8%±2.5% (maximum of 6% increase in V70) and reduces ipsilateral lung V20 by up to 3% (average decrease of 1.2%±1.3%). Contralateral lung V20, esophagus V25, and heart V30 are also reduced by up to 5%, 3%, and 3%. For the sixth case, lung tumor motion is on the order of the dose voxel size (3mm), and MAO did not improve upon the ITV plan.

CONCLUSIONS

Dose-volume optimization on a stationary image does not ensure accumulated dose coverage to the moving CTV. Multiple anatomy optimization can remove dose ambiguity and improve plan quality. P01CA11602 and Philips Medical Systems.

Comparisons of treatment optimization directly incorporating systematic patient setup uncertainty with a margin-based approach

PURPOSE

To develop a probabilistic treatment planning (PTP) method which is robust to systematic patient setup errors and to compare PTP plans with plans generated using a planning target volume (PTV) margin optimized to give the same target coverage probability as the PTP plan.

METHODS

Plans adhering to the RTOG-0126 protocol are developed for 28 prostate patients using PTP and margin-based planning. For PTP, an objective function that simultaneously considers multiple possible patient positions is developed. PTP plans are optimized using clinical target volume (CTV) structures and organ at risk (OAR) structures. The desired CTV coverage probability is 95%. Plans that cannot achieve a 95% CTV coverage probability are re-optimized with a desired CTV coverage probability reduced by 5% until the desired CTV coverage probability is achieved. Margin-based plans are created which achieve the same CTV coverage probability as the PTP plans by iterative adjustment of the CTV-to-PTV margin. Postoptimization, probabilistic dose-volume coverage metrics are used to compare the plans.

RESULTS

For equivalent target coverage probability, PTP plans significantly reduce coverage probability for rectum objectives (-17% for D(35) < 65 Gy, p = 0.0010; -23% for D(25) < 70 Gy, p < 0.0001; and -27% for D(15) < 75 Gy, p < 0.0001). Physician assessment indicates PTP plans are entirely preferred 71% of the time while margin-based plans are entirely preferred 7% of the time.

CONCLUSIONS

For plans having the same target coverage probability, PTP has potential to reduce rectal doses while maintaining CTV coverage probability. In blind comparisons, physicians prefer PTP plans over optimized margin plans.

Patient safety incidents associated with obesity: a review of reports to the National Patient Safety Agency and recommendations for hospital practice

BACKGROUND

The incidence and prevalence of obesity are increasing world wide. In the UK, obesity governmental strategy has primarily focused on prevention measures, with less focus on the demands of treating obese patients in hospital. Increasing service demand by obese patients coupled with a lack of adequate provision for care of these patients may lead to an increase in patient safety incidents. By classifying patient safety incidents associated with obesity reported to the National Patient Safety Agency, this report aims to identify areas for improvement in the quality and safety of care of the obese patient.

METHODS

A search of the National Reporting and Learning System database was conducted for all incidents caused by or relating to obesity for the period 1 January 2005 to 31 August 2008. The keywords 'obesity', 'overweight', 'BMI' (body mass index), and 'bariatric' were used. The relevant free text fields of the resulting set of incidents were then searched for the terms designed to isolate incidents occurring in anaesthesia, critical care, and surgery. Reported incidents were analysed and subsequently categorised to identify incident themes. Levels of harm were also established.

RESULTS

555 patient safety incidents were identified; 388 met inclusion criteria for analysis. 148 incidents were related to assessment, diagnosis or treatment, 213 related to infrastructure and 27 related to staffing. The majority of incidents were classified as no or low harm. Three deaths were reported, all within the domain of anaesthesia.

CONCLUSIONS

This report identifies that the majority of safety incidents associated with obesity were related to infrastructure, suggesting that there is inadequate provision in place for the care of obese patients. While levels of harm were mostly low, the occurrence of incidents resulting in severe harm or death highlights the specific dangers associated with the care of the obese patient. A global approach to improving the safety of care delivery for obese patients is recommended, including obesity specific training, management structures, care pathways, and equipment provisioning.Further planning and development of operation policies is needed to ensure the safe delivery of healthcare to obese patients in the future.

Excellence in teaching for promotion and tenure in animal and dairy sciences at doctoral/research universities: a faculty perspective

In this study, animal or dairy sciences faculty from doctoral/research universities were surveyed to clarify teaching performance expectations for the purpose of promotion and tenure of assistant professors. A survey tool including 15 evaluation criteria was available online and at the registration desk of the 2005 Joint Annual Meeting of the American Dairy Science Association and the American Society of Animal Science. The analyzed data set included 47 faculty (41 tenured and 6 tenure-track) with a substantial teaching responsibility from 27 different departments in 25 states. Four criteria were perceived as currently overemphasized: student evaluation of the instructor, student evaluation of the course, authoring peer-reviewed publications, and authoring an undergraduate textbook or book chapter. Nevertheless, more than 50% of respondents reported that these criteria should be used. One criterion emerged as being currently underemphasized: documentation of personal assessment of one's own teaching by preparing a portfolio. The lack of consensus for the remaining 10 items may have reflected substantial differences in institutional practices. The significance of overemphasis or underemphasis of certain criteria varied substantially depending on the respondent's perceived institutional mission. When asked about recognition within their department, 68% of respondents indicated that efforts in teaching improvement were properly rewarded. Respondents doubted the meaningfulness and appropriateness of student ratings tools as currently used. Results also suggested that animal and dairy science faculty placed a higher value on criteria recognizing excellence in teaching based on intradepartmental recognition (e.g., interactions with close-up peers and students) rather than recognition within a broader community of scholars as evidenced by authorship or success in generating funding for teaching. Proposed improvements in the evaluation of teaching for promotion and tenure include 1) providing tenure-track faculty with written guidelines at the time of hiring; 2) ensuring that student ratings tools are reliable and valid; 3) carefully mentoring new faculty within the departmental and institutional culture; and 4) encouraging self-reflection and documentation of attempts to address pedagogical issues in one's own teaching. Educational leaders in doctoral/research universities should promote changes to enhance teaching performance of future faculty graduating from their institutions.