Radiation necrosis or tumor progression? A review of the radiographic modalities used in the diagnosis of cerebral radiation necrosis.

PURPOSE: Cerebral radiation necrosis is a complication of radiation therapy that can be seen months to years following radiation treatment. Differentiating radiation necrosis from tumor progression on standard magnetic resonance imaging (MRI) is often difficult and advanced imaging techniques may be needed to make an accurate diagnosis. The purpose of this article is to review the imaging modalities used in differentiating radiation necrosis from tumor progression following radiation therapy for brain metastases. METHODS: We performed a review of the literature addressing the radiographic modalities used in the diagnosis of radiation necrosis. RESULTS: Differentiating radiation necrosis from tumor progression remains a diagnostic challenge and advanced imaging modalities are often required to make a definitive diagnosis. If diagnostic uncertainty remains following conventional imaging, a multi-modality diagnostic approach with perfusion MRI, magnetic resonance spectroscopy (MRS), positron emission tomography (PET), single photon emission spectroscopy (SPECT), and radiomics may be used to improve diagnosis. CONCLUSION: Several imaging modalities exist to aid in the diagnosis of radiation necrosis. Future studies developing advanced imaging techniques are needed.

The dilemma of radiation necrosis from diagnosis to treatment in the management of brain metastases.

Radiation therapy with stereotactic radiosurgery (SRS) or whole brain radiation therapy is a mainstay of treatment for patients with brain metastases. The use of SRS in the management of brain metastases is becoming increasingly common and provides excellent local control. Cerebral radiation necrosis (RN) is a late complication of radiation treatment that can be seen months to years following treatment and is often indistinguishable from tumor progression on conventional imaging. In this review article, we explore risk factors associated with the development of radiation necrosis, advanced imaging modalities used to aid in diagnosis, and potential treatment strategies to manage side effects.

Meta-Analysis of 5-Fraction Preoperative Radiotherapy for Soft Tissue Sarcoma.

OBJECTIVES: Studies investigating preoperative 5-fraction radiation therapy (RT) for soft tissue sarcoma (STS) are limited. We performed a meta-analysis to determine the efficacy and safety of this treatment paradigm. METHODS: This study-level meta-analysis was conducted using Bayesian methods. Statistical estimation for risk of outcome rates was conducted by posterior mean and 95% highest posterior density (HPD) intervals. Studies with 2-year local control (LC) and description of major wound complications (MWC) per the CAN-NCIC-SR2 study were included and served as the primary endpoints. Secondary endpoints included rates of acute and late toxicity. A total of 10 studies were identified and 7 met the inclusion criteria. Subgroup analyses were performed for ≥30 Gy vs <30 Gy. RESULTS: A total of 209 patients from 7 studies were included. Five studies used ≥30 Gy (n=144), and 2 studies <30 Gy (n=64). Median follow-up was 29 months (range: 21 to 57 mo). Primary tumor location was lower extremity in 68% and upper extremity in 22%. Most tumors were intermediate or high grade (95%, 160/169), and 50% (79/158) were >10 cm. The two-year LC for the entire cohort was 96.9%, and the rate of MWC was 30.6%. There was a trend toward improved LC with ≥ 30 Gy (95% HPD: 0.95 to 0.99 vs 0.84 to 0.99). There was no difference in MWC (95% HPD: 0.18 to 0.42 vs 0.17 to 0.55) or late toxicity between the groups. CONCLUSION: Preoperative 5-fraction RT for STS demonstrates excellent 2-year LC with MWC and toxicity similar to standard fractionation preoperative RT. Multi-institutional trials with a universal RT protocol are warranted.

Cancer Diagnoses and Use of Radiation Therapy Among Persons Experiencing Homelessness.

PURPOSE: Persons experiencing homelessness (PEH) have low rates of cancer screening and worse cancer mortality compared with persons not experiencing homelessness. Data regarding cancer diagnosis and treatment in PEH are limited. We investigated cancer prevalence and use of radiation therapy (RT) in PEH. METHODS AND MATERIALS: Patients presenting between January 1, 2014, and September 27, 2021, at a large metropolitan hospital system were assessed for homelessness via intake screening or chart search. PEH data were cross-referenced with the institution's cancer database to identify PEH with cancer diagnoses. Demographic, clinical, and treatment variables were abstracted. RESULTS: Of a total of 9654 (9250 evaluable) PEH with a median age of 42 years, 81 patients (0.88%) had at least 1 cancer diagnosis and 5 had multiple diagnoses, for a total of 87 PEH with at least 1 cancer diagnosis. The median age at diagnosis was 60 years. In total, 43% were female and 51% were Black, and 43% presented with advanced or metastatic disease. Lung (17%), prostate (15%), leukemia/lymphoma (13%), and head/neck (9%) were the most common diagnoses. In total, 17% of patients underwent surgery alone, 13% received chemotherapy alone, 14% received RT alone, and 6% received hormone therapy alone. A total of 8% of patients underwent no treatment, and 43% underwent multimodality therapy. In total, 58% of treated patients never achieved disease-free status. Of the 31 patients who received RT, 87% received external beam RT. Most patients (70%) received hypofractionated regimens. For patients who had multifraction treatment, the treatment completion rate was 85%, significantly lower than the departmental completion rate of 98% (P < .00001). CONCLUSIONS: In a large cohort of PEH in a metropolitan setting, cancer diagnoses were uncommon and were frequently in advanced stages. Most patients underwent single-modality treatment or no treatment at all. Despite the use of hypofractionation, the RT completion rate was low, likely reflecting complex barriers to care. Further interventions to optimize cancer diagnosis and treatment in PEH are urgently needed.

Early outcomes of ultra-hypofractionated preoperative radiation therapy for soft tissue sarcoma followed by immediate surgical resection.

BACKGROUND: There is increasing interest in shorter courses of radiation therapy (RT) in the management of soft tissue sarcoma (STS). We report our institutional experience for patients undergoing ultra-hypofractionated preoperative RT followed by immediate resection. METHODS: An IRB approved review of patients treated with preoperative 5 fraction, once daily RT followed by immediate resection (within 7 days) for STS of the extremity or trunk was conducted. The primary endpoints are major wound complications and local control (LC). Secondary endpoints include grade ≥ 2 toxicity, metastasis free survival (MFS), and overall survival (OS). RESULTS: Twenty-two patients with a median age of 67 years (range 30-87) and median follow-up of 24.5 months (IQR 17.0-35.7) met eligibility criteria; 18/22 patients (81.8 %) had ≥ 1 year follow-up. Primary tumor location was lower extremity in 15 patients (68.2 %), upper extremity in 5 (22.7 %), and trunk in 2 (9.1 %). All patients received 30 Gy in 5 fractions. The median time to resection following RT was 1 day (range 0-5). The median time from biopsy to resection was 34 days (range 20-69). Local control was 100 %; in patients with localized disease, 2-year MFS and OS were 71.3 % and 76.9 %, respectively. Major wound complications occurred in 9 patients (40.9 %), with wound complications requiring reoperation occurring in 8 patients (36.4 %). Other acute and late grade ≥ 2 toxicities were seen in 0 and 4 patients (18.2 %), respectively. CONCLUSION: Ultra-hypofractionated preoperative RT followed by immediate resection permits expedited completion of oncologic therapy with early results demonstrating excellent local control and acceptable toxicity. Prospective data with long-term follow-up is needed.

Prostate Cancer Screening Disparities in Persons Experiencing Homelessness.

PURPOSE: The purpose of this study was to assess prostate-specific antigen (PSA) testing rates in persons experiencing homelessness (PEH), identify factors associated with screening, and compare PSA screening rates in PEH with a matched cohort of persons not experiencing homelessness (non-PEH). MATERIALS AND METHODS: We identified 9,249 potentially eligible PEH cared for at a large metropolitan hospital system from an institutional registry of all patients who presented to the health care system as homeless from 2014 to 2021. Homelessness was defined by the presence of the Z-code for homelessness (Z59), the listed address matching to the address of a homeless shelter or other transitional housing or a positive screen for homelessness. A matched cohort of 10,000 non-PEH was generated for comparison. Univariate chi-square analysis and multivariate logistic regression were performed to evaluate variables associated with PSA testing. RESULTS: A total of 1,605 PEH and 3,413 non-PEH were eligible for PSA screening within the study timeframe. Half of PEH were Black (50%). Medicaid was the most common insurance (51%), followed by Medicare (18%). PEH were less likely to have a PCP (58% v 81%, P < .001) and had a significantly lower PSA testing rate (13% v 34%, P < .001) compared with non-PEH. Univariate analysis revealed that PSA testing was more common in PEH who were employed (P < .001), had private insurance or Medicare (P < .001), or had an established primary care provider (PCP; P < .001). Multivariate analysis confirmed that having a PCP (OR, 2.54; 95% CI, 1.62 to 4.00; P < .001) significantly increased the likelihood of PSA testing in PEH. CONCLUSION: PEH experience low rates of prostate cancer screening. Interventions to increase screening in this population, including increased PCP access, are needed.

Limited Toxicity of Hypofractionated Intensity Modulated Radiation Therapy for Head and Neck Cancer.

BACKGROUND/AIM: Hypofractionated radiation therapy is not commonly used in head and neck cancers (HNC) due to increased toxicity observed in historical cohorts. This study reviews our institutional experience using hypofractionated intensity modulated radiation therapy (H-IMRT) for HNC. PATIENTS AND METHODS: A retrospective cohort study of 56 patients with HNC treated with H-IMRT with ≥50 Gy in 20 fractions was conducted. The primary outcomes were acute and late toxicity. RESULTS: Two-year locoregional control was 87% and median overall survival was 46 months. There were no acute or late grade 4 or 5 toxicities. Acute grade 2 and 3 toxicity was seen in 79% (N=44) and 25% (N=14), respectively. Late grade 2 toxicity was seen in 9% (N=5). No patients required the placement of a feeding tube or tracheostomy. CONCLUSION: H-IMRT for the definitive or post-operative treatment of HNC using ≥50 Gy in 20 fractions appears safe and well tolerated with modest toxicity.