Rationale and Design of a Phase 1 Clinical Trial to Evaluate HSV G207 Alone or with a Single Radiation Dose in Children with Progressive or Recurrent Malignant Supratentorial Brain Tumors

Primary central nervous system tumors are the most common solid neoplasm of childhood and the leading cause of cancer-related death in pediatric patients. Survival rates for children with malignant supratentorial brain tumors are poor despite aggressive treatment with combinations of surgery, radiation, and chemotherapy, and survivors often suffer from damaging lifelong sequelae from current therapies. Novel innovative treatments are greatly needed. One promising new approach is the use of a genetically engineered, conditionally replicating herpes simplex virus (HSV) that has shown tumor-specific tropism and potential efficacy in the treatment of malignant brain tumors. G207 is a genetically engineered HSV-1 lacking genes essential for replication in normal brain cells. Safety has been established in preclinical investigations involving intracranial inoculation in the highly HSV-sensitive owl monkey (Aotus nancymai), and in three adult phase 1 trials in recurrent/progressive high-grade gliomas. No dose-limiting toxicities were seen in the adult studies and a maximum tolerated dose was not reached. Approximately half of the 35 treated adults had radiographic or neuropathologic evidence of response at a minimum of one time point. Preclinical studies in pediatric brain tumor models indicate that a variety of pediatric tumor types are highly sensitive to killing by G207. This clinical protocol outlines a first in human children study of intratumoral inoculation of an oncolytic virus via catheters placed directly into recurrent or progressive supratentorial malignant tumors.

Gait Speed and Survival in Patients With Brain Metastases

CONTEXT

Accurate estimation of life expectancy in patients with brain metastases is critical for counseling and choosing appropriate therapy. Performance status is the single greatest determinant of overall survival in this population. However, current measures of performance status are subjective and often based on brief clinical encounters. Gait speed is an objective, reliable predictor of overall health and survival.

OBJECTIVE

The purpose of this study was to evaluate the relationship between gait speed and survival in patients with brain metastases.

METHODS

We conducted a retrospective review of all patients with documented gait speed and Karnofsky performance status seen in consultation for newly diagnosed brain metastases from 2014 to 2015. Gait speed was measured during neurological examination over 4 m at normal pace. Graded prognostic assessment scores were calculated from clinical information. The primary outcomes were overall survival and 30-day mortality.

RESULTS

Eighty-five of 88 patients (97%) met inclusion criteria. Overall, the median gait speed was 0.7 m/s (range 0-1.0 m/s). Gait speed was associated with increased overall survival in addition to graded prognostic assessment score. Median survival was longer in patients with normal gait speed (>0.6 m/s, 11.9 months) compared to those with slow gait speed (≤0.6 m/s, 4.5 months, P < 0.001) or who were nonambulatory (1.1 months, P < 0.001). Thirty-day mortality for normal, slow, and nonambulatory patients was 0%, 15%, and 42%, respectively. The graded prognostic assessment overestimated actual survival for nonambulatory patients (2.2 vs. 1.1 months) and underestimated for those with normal gait speed (4.4 vs. 11.9 months).

CONCLUSION

Gait speed is associated with overall survival in patients with newly diagnosed brain metastases. Gait speed assessment is simple, objective, and may provide additional prognostic information to improve life expectancy estimation and management decisions.

A priori patient-specific collision avoidance in radiotherapy using consumer grade depth cameras

PURPOSE

In this study, we demonstrate and evaluate a low cost, fast, and accurate avoidance framework for radiotherapy treatments. Furthermore, we provide an implementation which is patient specific and can be implemented during the normal simulation process.

METHODS

Four patients and a treatment unit were scanned with a set of consumer depth cameras to create a polygon mesh of each object. Using a fast polygon interference algorithm, the models were virtually collided to map out feasible treatment positions of the couch and gantry. The actual physical collision space was then mapped in the treatment room by moving the gantry and couch until a collision occurred with either the patient or hardware. The physical and virtual collision spaces were then compared to determine the accuracy of the system. To improve the collision predictions, a buffer geometry was added to the scanned gantry mesh and performance was assessed as a function of buffer thickness.

RESULTS

Each patient was optically scanned during simulation in less than 1 min. The average time to virtually map the collision space for 64, 800 gantry/couch states was 5.40 ± 2.88 s. The system had an average raw accuracy and negative prediction rate (NPR) across all patients of 97.3% ± 2.4% and 96.9% ± 2.2% respectively. Using a polygon buffer of 6 cm over the gantry geometry, the NPR was raised to unity for all patients, signifying the detection of all collision events. However, the average accuracy fell from 95.3% ± 3.1% to 91.5% ± 3.6% between the 3 and 6 cm buffer as more false positives were detected.

CONCLUSIONS

We successfully demonstrated a fast and low cost framework which can map an entire collision space a priori for a given patient during the time of simulation. All collisions can be avoided using polygon interference, but a polygon buffer may be required to account for geometric uncertainties of scanned objects.

Quality of Prostate Cancer Treatment Information on Cancer Center Websites

INTRODUCTION

Cancer center websites are trusted sources of internet information about treatment options for prostate cancer. The quality of information on these websites is unknown. The objective of this study was to evaluate the quality of information on cancer center websites addressing prostate cancer treatment options, outcomes, and toxicity.

MATERIALS AND METHODS

We evaluated the websites of all National Cancer Institute-designated cancer centers to determine if sufficient information was provided to address eleven decision-specific knowledge questions from the validated Early Prostate Cancer Treatment Decision Quality Instrument. We recorded the number of questions addressed, the number of clicks to reach the prostate cancer-specific webpage, evaluation time, and Spanish and mobile accessibility. Correlation between evaluation time and questions addressed were calculated using the Pearson coefficient.

RESULTS

Sixty-three websites were reviewed. Eighty percent had a prostate cancer-specific webpage reached in a median of three clicks. The average evaluation time was 6.5 minutes. Information was available in Spanish on 24% of sites and 59% were mobile friendly. Websites provided sufficient information to address, on average, 19% of questions. No website addressed all questions. Evaluation time correlated with the number of questions addressed (R(2) = 0.42, p < 0.001).

CONCLUSIONS

Cancer center websites provide insufficient information for men with localized prostate cancer due to a lack of information about and direct comparison of specific treatment outcomes and toxicities. Information is also less accessible in Spanish and on mobile devices. These data can be used to improve the quality and accessibility of prostate cancer treatment information on cancer center websites.

Prolonged treatment with bevacizumab is associated with brain atrophy: a pilot study in patients with high-grade gliomas

Bevacizumab is widely used for treatment of high-grade gliomas and other malignancies. Because bevacizumab has been shown to be associated with neurocognitive decline, this study is designed to investigate whether prolonged treatment with bevacizumab is also associated with brain atrophy. We identified 12 high-grade glioma patients who received bevacizumab for 12 months at the first recurrence and 13 matched controls and blindly compared the volumes of the contralateral hemispheres and contralateral ventricle in these two groups at baseline and after 12 ± 2 months of the baseline scan by two independent analyses. The volumes of the contralateral hemispheres and ventricles did not differ significantly between the two groups at baseline. Whereas, in the control group the volumes of the contralateral hemisphere changed subtly from baseline to follow-up (p = 0.23), in the bevacizumab-treated group the volumes significantly decreased from baseline to follow-up (p = 0.03). There was significant increase in the contralateral ventricle volume from base line to follow-up scans in both the control group (p = 0.01) and in the bevacizumab group (p = 0.005). Both the absolute and the percentage changes of contralateral hemisphere volumes and contralateral ventricular volumes between the two patient groups were statistically significant (p < 0.05). Results of this study demonstrate prolonged treatment with bevacizumab is associated with atrophy of the contralateral brain hemisphere.

Treatment of adults with recurrent malignant glioma

Virtually all malignant gliomas recur. Treatment options at recurrence have relied upon surgical intervention, radiation therapy or cytotoxic chemotherapy. Unfortunately, none are associated with significant improvements in survival. Advances in treatment options at recurrence have been dependent upon the combination of surgical resection, focal radiation and chemotherapy. Despite aggressive interventions, few patients have meaningful improvements. Current research focuses on novel targeted molecular therapy that will hopeful be able to take advantage of advances in our understanding of the biology of glial neoplasms.

Stereotactic radiosurgical treatment of brain metastasis of primary tumors that rarely metastasize to the central nervous system

We evaluated the local control of gamma knife stereotactic radiosurgery (GKSRS) in the treatment of cerebral metastases from primary tumors that rarely metastasize to the central nervous system (CNS). There is little published data on this subject with very few series on specific primary tumors. We present our experience treating these lesions with GKSRS combined with a review of the salient literature. A retrospective study of 36 patients who collectively underwent 44 GKSRS procedures for CNS metastatic disease was undertaken. Our series includes four patients with sarcoma, two with prostate cancer, three with thyroid cancer, five with endometrial cancer, seven with ovarian cancer, two with cervical cancer, six with esophageal cancer, two with bladder cancer, one with liver cancer, one with pancreatic cancer, and three with testicular cancer. With 44 gamma knife sessions treating 74 tumors, 63 tumors showed no radiographic evidence of progression, and 13 tumors demonstrated radiographic progression between one and 12 months after gamma knife treatment. In six patients in the population, further treatment with GKSRS was necessary due to enlargement of untreated lesions or new metastatic disease. GKSRS for uncommon CNS metastases is appears to be efficacious in controlling the treated tumor. The majority of tumors treated in our study did not progress post gamma knife.