A Single-Institution Review of the Use of Radiation in the Adjuvant and Definitive Management of Keloids.

AIMS: Many individuals suffer from keloids that are refractory to standard treatment modalities, including surgical excision alone. Radiation therapy can be used to reduce the risk of recurrent keloids post-operatively, as well as be used as primary treatment for keloids not amenable to surgical resection. The purpose of this study was to review our institutional experience of radiation therapy for keloid management. MATERIALS AND METHODS: A retrospective review of patients treated with radiation therapy for keloids between 2014 and 2020 at our institution was performed. RESULTS: A total of 70 keloids in 41 patients were treated. For the 55 keloids treated with post-operative radiation therapy (16Gy delivered in 2 fractions), 82.5% (33/40) of evaluable lesions did not recur. Among the 15 keloids treated with definitive radiation therapy (24Gy delivered in 3 fractions), 78.6% (11/14) of evaluable keloids showed complete flattening, and 14.3% (2/14) had partial flattening. Both acute and late toxicities were mild, with only a single instance of grade 3 toxicity (dermatitis). CONCLUSION: Our study confirms that radiation therapy has a role in reducing the risk of keloid recurrence post-operatively, and plays an important role in the definitive management of unresectable keloids.

Severe kyphosis and stereotactic lung radiation therapy set-up: A case report and lessons learned.

INTRODUCTION: Stereotactic body radiation therapy (SBRT) for lung cancers allows for safe ablative radiation doses to be delivered precisely to treat localized stage 1 lung cancers and for the treatment of lung oligometastasis/es. The successful delivery of lung SBRT requires multidisciplinary technical expertise, from radiation oncologists, medical physicists, radiation therapists, and a clinical specialist radiation therapist in SBRT. While the majority of SBRT lung set-ups are routine, we present a challenging situation in the lung SBRT set-up for a patient with severe kyphosis. CASE AND OUTCOMES: An 80-year-old woman was diagnosed with a right upper lobe non-small cell lung cancer. She declined surgery and was referred for lung SBRT. Her severe kyphosis did present challenges in terms of reproducible lung SBRT set-up. We were successful in immobilizing this patient in a vacuum customized rigid support which was shaped to accommodate this patient's extreme kyphosis and elevated head. The patient tolerated the treatment position and successfully completed her lung SBRT treatments comfortably, without any reproducibility issues. Four months after SBRT, the patient was doing well without any new chest symptoms. DISCUSSION: This report is the first, in the published medical literature, to describe a lung SBRT set-up for a patient with extreme kyphosis. Her successful set-up and ability to complete her lung SBRT was dependent on creative problem-solving from the multi-disciplinary team and a patient-centred approach to care CONCLUSION: Multidisciplinary collaboration was essential in the successful SBRT treatment for a severely kyphotic patient. The use of a vacuum customized thoracic rigid support was effectively used in a patient with severe kyphosis for lung SBRT. Results from this case report could be useful and guide other clinicians if presented with similarly challenging cases.

Evolution and Evaluation of a Structured Applied Physics Course for Radiation Oncology and Radiation Physics Trainees.

We sought to supplement medical physics textbook knowledge and clinical learning with case-based discussions. To our knowledge, this is the first report on a structured combined applied physics curriculum for radiation oncology (RO) and medical physics (MP) trainees. We reviewed our yearly applied physics course given from the years 2016-2021 inclusive. The number of applied physics trainees ranged from 7 to 14 per year (2-9 RO and 3-6 MP residents per year). Each session was taught by a pair of (RO and MP) faculty members. Twenty-nine case-based sessions were given yearly (2016 to 2019). Because of the COVID-19 pandemic restrictions, the course was shortened to 8 case-based sessions in 2020 and 2021. For the years 2016-2021, the mean and median teaching evaluation scores were 4.65 and 5, respectively (range 2-5), where 1 represents worse teaching quality and 5, the best teaching quality. For the year 2021, 2 questions relating to the video virtual format (implemented due to the covid-19 pandemic), revealed consistent high scores with the mean and median responses of 4.14 and 5, respectively (range 1-5). The results from the teaching evaluation scores indicate that the trainees highly valued the teaching sessions and teachers. Our experience indicates that a case-based applied physics course was delivered successfully with continued high teaching evaluation scores. A video virtual platform for an applied physics course could be useful, especially for small programs without a structured applied physics curriculum.

Hypofractionated Radiation Therapy in Keratinocyte Carcinoma.

Hypofractionated radiation therapy regimens are well suited to the management of keratinocyte carcinomas. Most lesions are small, superficial and not close to critical organs at risk. Fewer visits to the cancer centre are advantageous for the frail and elderly patient population. No difference in cosmesis or local control has been found when comparing hypofractionated with conventionally fractionated radiation therapy schedules, although most of the data in the literature are retrospective, highlighting the need for prospective trials. As keratinocyte carcinomas can present anywhere on the skin surface, a wide variety of techniques may be used to optimise treatment delivery, including external beam radiation with kilovoltage, electron beams and megavoltage photons. Brachytherapy can also be used with radionuclide and electronic-based applicators, surface applicators and interstitial techniques for lesions >5 mm deep. Stereotactic body radiotherapy, or extreme hypofractionation, is an emerging treatment option that delivers an ablative dose to the tumour while minimising dose to organs at risk through precision planning and delivery techniques. Frail elderly patients with medically inoperable disease not suitable for conventionally fractionated radiation therapy may achieve durable locoregional control with dose escalation. Ongoing studies following local control and toxicity are warranted. The aim of this article is to provide clinical oncologists with an overview of hypofractionation for keratinocyte carcinomas.

Survival outcomes in elderly patients with glioblastoma.

AIMS: Many elderly glioblastoma patients are excluded from randomised trials due to age, comorbidity or poor functional status. The purpose of this study was to describe the survival outcomes in all elderly patients with glioblastoma managed at a tertiary cancer centre. MATERIALS AND METHODS: A retrospective chart review identified 235 elderly patients (age 65 years or over) with a histological diagnosis of glioblastoma between 1 December 2006 and 31 December 2013. The primary outcome of this study was overall survival by treatment type. Univariate and multivariate Cox proportional hazard models were used to explore significant prognostic variables associated with overall survival. RESULTS: The median survival for all patients was 6.5 months (95% confidence interval 5.3-7.7), with 1 year overall survival of 23.7% (95% confidence interval 18.8-30.0). The median survival for patients treated with radiation and chemotherapy was 11.1 months (95% confidence interval 8.1-13.7). Patients treated with radiation alone had a median survival of 6.8 months (95% confidence interval 5.6-7.9). For patients managed with comfort measures only, the median survival was 1.9 months (95% confidence interval 1.6-2.6). Univariate analysis revealed age, performance status, surgery type (biopsy, subtotal resection, gross total resection) and type of treatment received (comfort measures only, radiotherapy alone, radiotherapy and chemotherapy) to be statistically associated with overall survival. In the multivariate analysis, only two predictive factors (treatment received and surgery type) were significant. CONCLUSIONS: Elderly patients with glioblastoma selected for treatment (surgery followed by radiation alone or radiation and chemotherapy) survive longer than patients managed with comfort measures. Prospective randomised trials will help guide management for patients eligible for therapy. Elderly patients with glioblastoma who are deemed not eligible for active therapy have very short survival.

Predictors of recurrence after radiotherapy for non-melanoma skin cancer.

Predictive factors of recurrence were examined in 448 non-melanoma skin cancers (72% basal cell carcinoma, 28% squamous cell carcinoma) treated with radiotherapy. The overall recurrence rate was 15.8% at a median follow-up of 18.4 months. In multivariate analysis, significant factors for recurrence were age (p = 0.0197), tumour size 2 cm or greater (p = 0.0095), immunosuppression (p = 0.0082), and treatment modality (p = 0.0009).

International practice survey on the management of brain metastases: Third International Consensus Workshop on Palliative Radiotherapy and Symptom Control.

AIM: To evaluate international patterns of practice for the management of metastatic disease to the brain. MATERIALS AND METHODS: An online international practice survey was conducted from April to June 2010. Most of the survey questions were based on common management issues for which optimal management using level 1 evidence was lacking. The survey consisted of three sections: respondent demographics, 13 general questions regarding surgery, whole brain radiotherapy (WBRT) and radiosurgery and 13 questions related to specific scenarios. RESULTS: In total, 445 individuals responded to the survey over a 3 month period. Ninety per cent of respondents worked in a hospital-based setting. Ninety-three per cent of respondents were radiation oncologists. Thirty-seven per cent worked in an academic setting. Only three of 26 survey questions generated at least 70% agreement for a favoured response. Eighty-eight per cent of respondents chose comfort measures only for patients with multiple brain metastases who have been previously treated with WBRT and who now present 6 months later with two to four brain metastases (all less than 4 cm in size) with uncontrolled extracranial disease and bedridden state. Seventy-eight per cent of respondents would use WBRT alone for initial treatment in patients with two to four brain metastases (all less than 4 cm in size), with active, uncontrolled extracranial disease and a Karnofsky performance status of 70. Seventy-eight per cent of respondents chose surgical resection for an enlarging single brain metastasis that has been previously treated with radiosurgery. The enlarging single brain metastasis is in a surgically accessible site and is now symptomatic. The patient has controlled extracranial disease, good performance status and magnetic resonance spectroscopy was not diagnostic. CONCLUSIONS: There is a lack of uniform agreement for many common management issues (not well answered by level 1 evidence) in patients with metastatic disease to the brain.

Did the pattern of practice in the prescription of palliative radiotherapy for the treatment of uncomplicated bone metastases change between 1999 and 2005 at the rapid response radiotherapy program?

AIMS: Since 1999, randomised clinical trials and meta-analyses have reported equal efficacy of pain relief from single- and multiple-fraction radiotherapy for bone metastases. A number of factors, including limited radiotherapy resources, waiting times, and patient convenience, suggest single fraction to be the treatment of choice for patients. However, international patterns of practice indicate that multiple fractions are still commonly used. This study examined whether dose-fractionation schemes used for the treatment of bone metastases at the Rapid Response Radiotherapy Program (RRRP) at the Odette Cancer Centre have changed since 1999. MATERIALS AND METHODS: A retrospective review of the prospective RRRP database and hospital records were conducted for all patients treated with palliative radiotherapy for uncomplicated bone metastases at the RRRP in 1999 (or baseline), 2001, 2004 and from 1 January to 31 July 2005. Data were collected on patient demographics and clinical characteristics. RESULTS: Of the 693 patients, 65 and 35% were prescribed single fraction (predominantly single 8 Gy) and multiple fractions (predominantly 20 Gy/five fractions), respectively. The administration of single treatments generally increased over time, from 51% in 1999 to 66% in 2005 (P=0.0001). On the basis of multiple logistic regression analyses, patients were more likely to be prescribed single-fraction radiotherapy if they had prostate cancer, had a poorer performance status, were treated to the limbs, hips, shoulders, pelvis, ribs, scapula, sternum, or clavicle (compared with the spine), were treated by a radiation oncologist who had been trained in earlier years, and who were treated after 1999. CONCLUSIONS: Between 1999 and 2005, the use of single-fraction radiotherapy increased, corresponding to publications showing equal efficacy of pain relief between single and multiple fractions in the management of uncomplicated bone metastases. However, about a third of patients still received multiple fractions.

Liquid embolisation material reduces the delivered radiation dose: a physical experiment.

OBJECTIVE: To test a new hypothesis that the glue/contrast admixture used for embolisation reduces the dose delivered to AVMs using an experimental model. METHOD: A model was created using a block of "solid water" (6 x 5 x 2 cm) with twelve wells of different depths. Different concentrations of the glue admixture (Enbucrilate + Lipiodol) were used. The model was irradiated using a 5MV beam with a clinical LINAC system and the dose was checked upstream and downstream. Dose was measured using Kodak XV film, a Vidar 16 bit film scanner and software for therapeutic film dosimetry measurements (RIT software). RESULTS: The radiation dose varied with the distance beyond the glue solid water interface. For distances of 0, 2 and 5 mm to the film, the mean reduction was 13.65% (SD = 2.94), 6.87% (SD = 1.95) and 1.75% (SD = 1.14), respectively. There was also correlation with the Lipiodol concentration in the mixture. The maximum reductions for 80, 50 and 20% Lipiodol concentrations were 16.1% (SD = 1.32), 14.85% (SD = 0.98) and 10% (SD = 1.21), respectively. There was no correlation between the glue depth and the dose delivered. CONCLUSION: The hypothesis that the glue mixture used for embolisation reduces the radiation dose delivered was experimentally confirmed with this study.

Whole brain radiotherapy for the treatment of multiple brain metastases.

BACKGROUND: Brain radiotherapy is used to treat cancer patients who have brain metastases resulting from various primary malignancies. OBJECTIVES: To assess the effectiveness and adverse effects of whole brain radiotherapy (WBRT) in adult patients with multiple metastases to the brain. SEARCH STRATEGY: CENTRAL (The Cochrane Library), MEDLINE, EMBASE, CANCERLIT, and CINAHL were searched. SELECTION CRITERIA: Randomized controlled trials (RCTs) in which adult patients with multiple metastases to the brain from any primary cancer and treated with WBRT were included. Trials of prophylactic WBRT were excluded as well as trials that dealt with surgery or WBRT, or both, for the treatment of a single brain metastasis. DATA COLLECTION AND ANALYSIS: Two review authors independently abstracted information for each predetermined outcome: overall survival at six months, intracranial progression-free duration, local brain response, local brain control, quality of life, symptom control, neurological function, and the proportion of patients able to reduce the daily dexamethasone dose. Adverse effects were also collected. MAIN RESULTS: Eight published reports (nine trials) showed no benefit of altered dose-fractionation schedules as compared to control fractionation (3000 cGy in 10 fractions) of WBRT on the probability of survival at six months. These studies also showed no difference in symptom control nor neurologic improvement among the different dose-fractionation schemes. The addition of radiosensitizers, in five RCTs, did not confer additional benefit to WBRT in either overall median survival times or brain tumor response rates. The addition of the radiosensitizer motexafin gadolinium did not improve quality of life nor time to neurologic progression overall. For the radiosensitizer misonidazole, there was no improvement in Karnofsky performance score outcomes. Three RCTs found no benefit in overall survival with the use of WBRT and a radiosurgery boost as compared to WBRT alone for selected patients with multiple brain metastases (up to four brain metastases). Overall, however, there was a statistically significant improvement in local brain control favoring the whole brain radiotherapy and radiosurgery boost arm. Only one trial of radiosurgery boost with WBRT reported an improved Karnofsky performance score outcome and improved ability to reduce dexamethasone dose. One RCT examined the use of WBRT and prednisone versus prednisone alone and produced inconclusive results. AUTHORS' CONCLUSIONS: None of the RCTs with altered dose-fractionation schemes as compared to standard delivery (3000 cGy in ten fractions) found a benefit in terms of overall survival, neurologic function, or symptom control. The use of radiosensitizers or chemotherapy in conjunction with WBRT remains experimental. A radiosurgery boost with WBRT may improve local disease control in selected patients, although survival remains unchanged. The benefit of WBRT as compared to supportive care alone has not been studied in RCTs. It may be that supportive care alone, without WBRT, may be appropriate for some patients, particularly those with advanced disease and poor performance status.

The do-not-resuscitate order: incidence of documentation in the medical records of cancer patients referred for palliative radiotherapy.

Patients with symptomatic metastases referred for outpatient palliative radiotherapy for symptom control at the Rapid Response Radiotherapy Program (RRRP) and the Bone Metastases Clinic (BMC) at the Toronto-Sunnybrook Regional Cancer Centre have a limited life expectancy. Relevant medical information is missing from the files of many referred patients when they arrive at the clinics, potentially causing delayed treatment and ambiguity in the best management of their needs in situations of worsening condition. Clear documentation of the do-not-resuscitate (DNR) order is imperative to avoid panic and the taking of unnecessarily aggressive measures in situations in which cardiopulmonary resuscitation (CPR) has no benefit or is not desired. Here, we report the current practices of CPR code status documentation for patients referred to the RRRP and the BMC for out-patient palliative radiotherapy.We reviewed referral notes and accompanying medical records for 209 consecutive patients seen in the RRRP and the bmc during May-August 2004 for documentation of CPR-related advance directives. Patient demographics and cancer history were also recorded.Only 13 (6.2%) of the 209 patients had any documented reference to CPR code status. Of these 13 patients, 8 were DNR-coded, and 5 were full code. As compared with patients having no documented cpr code status, patients with documented status were significantly older (median age: 77 years; p = 0.0347), had poorer performance status (median Karnofsky performance status score: 40; p = 0.0001), and were more likely to be referred hospital inpatients (69%, p = 0.0004).Only a small proportion of symptomatic advanced cancer patients had any documentation of CPR code status upon referral for outpatient palliative radiotherapy. In future, our clinics plan to request information about CPR code status on our referral form.

Supportive care management of brain metastases: what is known and what we need to know. Conference proceedings of the National Cancer Institute of Canada (NCIC) Workshop on Symptom Control in Radiation Oncology.

OBJECTIVES: To review the results of published randomised controlled trials in the treatment of brain metastases and, from the knowledge gained from these trials, to identify potential study questions. MATERIALS AND METHODS: The literature was searched for randomised controlled trials that dealt with the management of brain metastases. Potential research questions were identified on the basis of the results of the literature review. RESULTS: A number of research questions were identified. In the context of the NCIC Symptom Control Group, a trial of supportive care alone vs supportive care and whole-brain radiotherapy (WBRT) in a subset of patients with the diagnosis of brain metastases was deemed to be of highest priority. We discussed a number of issues relating to the feasibility of such a trial. CONCLUSIONS: The optimal management of brain metastases remains elusive. Despite the results of numerous randomised controlled trials, many questions remain unanswered. The magnitude of benefit using WBRT above supportive care alone is uncertain. A trial of supportive care alone vs supportive care and WBRT may be successful once target population, feasibility and methodological issues are thoroughly solved.

Radiosurgery and radiotherapy for non-small-cell lung cancer metastatic to brain.

Non-small-cell lung cancer metastatic to brain represents a common problem in oncology. Treatment modalities include stereotactic radiosurgery (SRS), whole-brain radiotherapy (WBRT), surgical resection, supportive care, or a combination of these options. This review outlines therapeutic strategies for treatment with particular attention to the use of SRS. Radiosurgical technique, radiobiology, dose prescription, patient selection, and results of therapy are discussed. The term SRS describes a radiation procedure that utilizes a three-dimensional stereotactic localization system to precisely treat small intracranial targets with a single, large, highly focal radiation dose. Stereotactic radiosurgery is appealing for several reasons; it is minimally invasive, easily tolerated, and highly effective, and patients return to normal baseline function within 24 hours. Stereotactic radiosurgery provides much higher control rates of treated lesions than does WBRT. Randomized trials are underway to ascertain the optimal role and timing of SRS in relation to WBRT in order to maximize control, survival, quality of life, and neuropsychological outcome.

Upregulation of vascular endothelial growth factor is associated with radiation-induced blood-spinal cord barrier breakdown.

The pathogenesis of radiation-induced injury to the central nervous system (CNS) remains unclear. Dysfunction of the blood-brain barrier (BBB) is associated with radiation-induced white matter lesions. The aim of this study was to determine if vascular endothelial growth factor (VEGF) is implicated in radiation-induced BBB disruption. Adult rats were irradiated with a single dose of 8 or 22 Gy to the spinal cord from C2 to T2. At various times up to 20 weeks following irradiation, blood-spinal cord barrier (BSCB) permeability was assessed using immunohistochemistry with anti-albumin antibody. Cell proliferation was assessed using bromodeoxyuridine (BrdU), and endothelial cell identity was assessed morphologically and using immunostaining for factor VIII-related antigen. Expression of VEGF protein and message was assessed using immunohistochemistry and in situ hybridization respectively. In the unirradiated rat spinal cord, there was no evidence of albumin immunoreactivity and little evidence of VEGF expression. After a dose of 22 Gy, focal albumin staining in white matter was observed at 16 weeks. Diffuse staining was seen at 20 weeks and was associated with necrosis and demyelination in white matter. This was associated with a significant increase in white matter glial cells that showed immunoreactivity and in situ hybridization signal for VEGE VEGF expressing cells showed dual immunoreactivity for glial fibrillary acidic protein. No increase in VEGF positive cells was observed in gray matter after 22 Gy. After a dose of 8 Gy, there was no increase in VEGF expression or albumin immunostaining in either white or gray matter. Microvessel endothelial cell density showed a trend towards a decrease with time after 22 Gy as compared with 8 Gy or unirradiated controls. BrdU immunostaining provided no evidence for endothelial cell proliferation in control or in the irradiated spinal cord. It is concluded that radiation-induced BSCB dysfunction is associated with upregulation of VEGF in astrocytes without associated endothelial proliferation. The temporal and spatial association of VEGF upregulation with the white matter lesions suggests a role of VEGF in radiation-induced late CNS injury.

Radiation therapy for benign central nervous system disease.

The most common indication for the use of radiation therapy in the treatment of benign central nervous system disease is for the treatment of benign brain tumors, such as meningioma, pituitary adenoma, acoustic neuroma, arteriovenous malformation, and craniopharyngioma. Other less common benign intracranial tumors treated with radiation include chordoma, pilocytic astrocytoma, pineocytoma, choroid-plexus papilloma, hemangioblastoma, and temporal bone chemodectomas. Benign conditions, such as histiocytosis X, trigeminal neuralgia, and epilepsy, are also amenable to radiation treatment. There have also been reports of radiosurgery being used for the treatment of movement disorders and psychiatric disturbances, such as obsessive-compulsive and anxiety disorders. For benign brain tumors, radiation therapy as either primary or adjuvant therapy plays an integral role in improving local control. In the treatment of trigeminal neuralgia, epilepsy, tremor, and some psychiatric disturbances, radiosurgery may help ameliorate or eliminate some symptoms. Patients with benign central nervous system disease are expected to live a long time. As such, treatment should be highly conformal and based on three-dimensional planning using magnetic resonance imaging, computed tomography, or both. It is critical that damage to normal brain be minimized.