Faculty Bibliography

BACKGROUND AND PURPOSE/OBJECTIVE:Radiation-induced contrast enhancements (RICE) are a common side effect following radiotherapy for glioma, but both diagnosis and handling are challenging. Due to the potential risks associated with RICE and its challenges in differentiating RICE from tumor progression, it is critical to better understand how RICE prognosis depends on iatrogenic influence. MATERIALS AND METHODS/METHODS:We identified 99 patients diagnosed with RICE who were previously treated with either photon or proton therapy for World Health Organization (WHO) grade 1-3 primary gliomas. Post-treatment brain MRI-based volumetric analysis and clinical data collection was performed at multiple time points. RESULTS:The most common histologic subtypes were astrocytoma (50%) and oligodendroglioma (46%). In 67%, it was graded WHO grade 2 and in 86% an IDH mutation was present. RICE first occurred after 16 months (range: 1-160) in median. At initial RICE occurrence, 39% were misinterpreted as tumor progression. A tumor-specific therapy including chemotherapy or re-irradiation led to a RICE size progression in 86% and 92% of cases, respectively and RICE symptom progression in 57% and 65% of cases, respectively. A RICE-specific therapy such as corticosteroids or Bevacizumab for larger or symptomatic RICE led to a RICE size regression in 81% of cases with symptom stability or regression in 62% of cases. CONCLUSIONS:While with chemotherapy and re-irradiation a RICE progression was frequently observed, anti-edematous or anti-VEGF treatment frequently went along with a RICE regression. For RICE, correct diagnosis and treatment decisions are challenging and critical and should be made interdisciplinarily.

BACKGROUND:Proton beam radiotherapy (PBT) offers physical dose advantages that might reduce the risk for secondary malignancies (SM). The aim of the current study is to calculate the risk for SM after X-ray-based 3D conformal (3DCRT) radiotherapy, intensity-modulated radiotherapy (IMRT), and active pencil beam scanned proton therapy (PBS) in patients treated for thymic malignancies. METHODS:Comparative treatment plans for each of the different treatment modalities were generated for 17 patients. The risk for radiation-induced SM was estimated using two distinct prediction models-the Dasu and the Schneider model. RESULTS:≤ 0.001). CONCLUSIONS:PBS achieved superior sparing of relevant OARs compared to 3DCRT and IMRT, leading to a lower risk for radiation-induced SM. PBS should therefore be considered in patients diagnosed with thymic malignancies, particularly young female patients.

Purpose/UNASSIGNED:Proton beam radiotherapy (PBT) has been used for the definitive treatment of localized prostate cancer with low rates of high-grade toxicity and excellent patient-reported quality-of-life metrics. Technological advances such as pencil beam scanning (PBS), Monte Carlo dose calculations, and polyethylene glycol gel rectal spacers have optimized prostate proton therapy. Here, we report the early clinical outcomes of patients treated for localized prostate cancer using modern PBS-PBT with hydrogel rectal spacing and fiducial tracking without the use of endorectal balloons. Materials and Methods/UNASSIGNED:This is a single institutional review of consecutive patients treated with histologically confirmed localized prostate cancer. Prior to treatment, all patients underwent placement of fiducials into the prostate and insertion of a hydrogel rectal spacer. Patients were typically given a prescription dose of 7920 cGy at 180 cGy per fraction using a Monte Carlo dose calculation algorithm. Acute and late toxicity were evaluated using the Common Terminology Criteria for Adverse Events (CTCAE), version 5. Biochemical failure was defined using the Phoenix definition. Results/UNASSIGNED:From July 2018 to April 2020, 33 patients were treated (median age, 75 years). No severe acute toxicities were observed. The most common acute toxicity was urinary frequency. With a median follow-up of 18 months, there were no high-grade genitourinary late toxicities; however, one grade 3 gastrointestinal toxicity was observed. Late erectile dysfunction was common. One treatment failure was observed at 21 months in a patient treated for high-risk prostate cancer. Conclusion/UNASSIGNED:Early clinical outcomes of patients treated with PBS-PBT using Monte Carlo-based planning, fiducial placement, and rectal spacers sans endorectal balloons demonstrate minimal treatment-related toxicity with good oncologic outcomes. Rectal spacer stabilization without the use of endorectal balloons is feasible for the use of PBS-PBT.

OBJECTIVE:The purpose of this study is to compare oncologic and functional outcomes of men with unilateral, localized PCa treated with stereotactic body radiotherapy (SBRT) versus focal cryoablation (FC). METHODS:Patients from our IRB-approved PCa database who underwent FC or SBRT and were eligible for both treatments were included. Patients with less than 1 year of follow-up or prior PCa treatment were excluded. The primary outcome was treatment failure, defined as salvage treatment or a Gleason group (GG) of ≥ 2 on post-treatment biopsy. Biochemical recurrence (BCR) was evaluated with Phoenix. Functional outcomes were based on EPIC surveys. Complications were categorized with the CTCAE 5.0. Outcomes were compared using descriptive statistics, univariate analyses, and Kaplan-Meier curve for failure-free survival (FFS) and BCR-free survival. P < 0.05 was significant. RESULTS:68 FC and 51 SBRT patients with a median age of 68 years (48-86) and a median follow-up time of 84 (70-101) months were included in this analysis. There was no difference in tumor risk (p = 0.47), GG (p = 0.20), or PSA (p = 0.70) among the two cohorts at baseline. At 7-year follow-up, no difference in FFS was found between the two cohorts (p = 0.70); however, significantly more FC patients had BCR (p < 0.001). At 48 months, no differences existed in urinary or bowel function; however, SBRT patients had significantly worse sexual function (p = 0.032). CONCLUSION/CONCLUSIONS:FC and SBRT are associated with similar oncologic and functional outcomes 7-year post-treatment. These results underscore the utility of FC and SBRT for the management of unilateral low-to-intermediate-risk PCa.

OBJECTIVE:To review quality-of-life (QoL) metrics between patients who underwent definitive stereotactic body radiotherapy (SBRT) versus active surveillance (AS) for management of low- to intermediate-risk prostate cancer (PCa). METHODS:A prospectively maintained PCa database was reviewed containing results of patient-reported QoL surveys. Patients with localized disease who chose AS or SBRT and completed at least one survey within four years of treatment were included. Patients who received salvage therapy were excluded. Survey results were compared across time using mixed-effects repeated measures analysis of covariance models that adjusted for factors significant in univariate analysis. A group x time interaction effect was examined to compare rate of change over time between AS and SBRT. P < 0.05 was significant. RESULTS:148 AS and 161 SBRT patients were included. Significantly more SBRT patients had intermediate-risk disease (p < 0.0001). AS had significantly worse sexual function compared to SBRT across time. While not significant, bowel function scores were lower for SBRT patients across time points. SBRT patients had significantly lower anxiety than AS patients at 24 months (p < 0.011) and 36 months (p < 0.010). Urinary function though worse in SBRT patients at 12 months in EPIC, was not significantly different in both groups across time points. CONCLUSION/CONCLUSIONS:SBRT patients have excellent QoL compared to AS with regard to anxiety post treatment. Though SBRT patients initially have worse urinary and bowel function than AS, scores were eventually similar in both cohorts by 48 months. SBRT patients have significantly worse sexual function post treatment. This study may help facilitate counseling in patients choosing PCa treatment.

Purpose/UNASSIGNED:Whole gland cryoablation is a guideline-approved definitive treatment for localized prostate cancer, and is being explored for partial gland ablation. However, there is limited data regarding management of cryoablation failures. Stereotactic body radiation therapy (SBRT) is a well-established method of primary treatment for prostate cancer. Here we review salvage SBRT after cryoablation failures. Methods and Materials/UNASSIGNED:A large database of patients treated with definitive SBRT was interrogated to identify those who underwent primary cryoablation. All patients were determined to have progressive disease based on a rising prostate specific antigen and/or postcryoablation biopsy. All patients were treated with SBRT over 5 treatment fractions using a robotic radiosurgical platform. Baseline cryoablation characteristics and pre- and posttreatment Expanded Prostate Cancer Index Composite questionnaires were analyzed. Acute and late toxicity was evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0. Cancer outcomes after salvage SBRT were stratified by disease and treatment characteristics. Results/UNASSIGNED:A total of 51 patients were identified who underwent cryoablation followed by salvage SBRT. The majority (47%) were found to have intermediate-risk disease at the time of SBRT salvage and most commonly were treated with 3500 cGy in 5 fractions to the prostate and seminal vesicles. Only 1 grade 3+ toxicity was identified. Patient-reported quality of life metrics after SBRT salvage followed prior patterns observed in the de novo SBRT setting. With a median follow-up of 40 months, 76% of the cohort demonstrated disease control. Median time to prostate cancer recurrence was 57.5 months, and recurrence was predominantly seen in patients with underlying high-risk disease. Conclusions/UNASSIGNED:This is the largest cohort of patients treated with any radiation therapy salvage after cryoablation and the first institution to report SBRT as a modality of salvage. Salvage SBRT after cryoablation results in low rates of high-grade toxicity, acceptable changes in patient-reported quality of life, and durable rates of long-term oncologic control.

In this review we outline the current evidence for the use of hydrogel rectal spacers in the treatment paradigm for prostate cancer with external beam radiation therapy. We review their development, summarize clinical evidence, risk of adverse events, best practices for placement, treatment planning considerations and finally we outline a framework and rationale for the utilization of rectal spacers when treating unfavorable risk prostate cancer with dose escalated Stereotactic Body Radiation Therapy (SBRT).

BACKGROUND AND PURPOSE/OBJECTIVE:Proton beam radiotherapy (PRT) is used in the treatment of low-grade glioma (LGG) to mitigate long-term sequelae. Following PRT, increased rates of radiation-induced contrast enhancements (RICE) are suspected but poorly understood. MATERIALS AND METHODS/METHODS:We analyzed consecutive 227 patients (42 children and 185 adults) treated with PRT (54Gy RBE) for LGG from 2010 to 2020 and followed with serial clinical exams and magnetic resonance imaging for in median 5.6 years. RESULTS:Tumors were graded WHO 1 in a minority (n = 22, 12%) of adults, but a majority of children (n = 29, 69%). In contrast, tumors were graded WHO 2 in the majority (n = 160, 87%) of adults and a minority of children (n = 10, 24%). Five-year overall survival following PRT was 81% in adults and 91% in children. The risk of RICE was 5-fold more frequent in adults (25%) versus children (5%) (p = 0.0043). In children and adults, RICE were symptomatic in 50% and 55% (n=1 and 26) of cases with CTCAE grade 0 in 47% (n=23), grade 1 in 25% (n=12), 0% grade 2 (n=0) and 29% grade 3 (n=14), respectively. In adults, RICE risk was associated to WHO grading (8% in WHO grade 1 vs. 24% in WHO grade 2, p = 0.026), independent of age (p=0.44) and irradiation dose (p=0.005), but not independent of IDH mutational status. CONCLUSIONS:These data demonstrate effectiveness of PRT for LGG in both children and adults. The RICE risk is lower in children which are a main target group for PRT and differs with WHO grading.

Pain, fatigue, and depression are a common cluster of symptoms among cancer patients that impair quality of life and daily activities. We aimed to evaluate the burden of cancer rehabilitation and return-to-work (RTW) rates. Tumor characteristics, lifestyle and household details, treatment data, the use of in-house social services and post-treatment inpatient rehabilitation, and RTW were assessed for 424 women, diagnosed with cervical, uterine, or vaginal/vulvar cancer, receiving curative radio(chemo)therapy. Progression-free RTW rate at 3 months was 32.3%, and increased to 58.1% and 63.2% at 12 and 18 months, respectively. Patients with advanced FIGO stages and intensified treatments significantly suffered more from acute pain and fatigue. A higher Charlson-Comorbidity-Index reliably predicted patients associated with a higher risk of acute fatigue during RT. Aside from the presence of children, no other household or lifestyle factor was correlated with increased fatigue rates. Women aged ≤ 45 years had a significantly higher risk of developing depression requiring treatment during follow-up. Post-treatment inpatient cancer rehabilitation, including exercise and nutrition counseling, significantly relieved fatigue symptoms. The burdens for recovery from cancer therapy remain multi-factorial. Special focus needs to be placed on identifying high-risk groups experiencing fatigue or pain. Specialized post-treatment inpatient cancer rehabilitation can improve RTW rates.