Radiation enhancement using focussed ultrasound-stimulated microbubbles for breast cancer: A Phase 1 clinical trial.

BACKGROUND: Preclinical studies have demonstrated that tumour cell death can be enhanced 10- to 40-fold when radiotherapy is combined with focussed ultrasound-stimulated microbubble (FUS-MB) treatment. The acoustic exposure of microbubbles (intravascular gas microspheres) within the target volume causes bubble cavitation, which induces perturbation of tumour vasculature and activates endothelial cell apoptotic pathways responsible for the ablative effect of stereotactic body radiotherapy. Subsequent irradiation of a microbubble-sensitised tumour causes rapid increased tumour death. The study here presents the mature safety and efficacy outcomes of magnetic resonance (MR)-guided FUS-MB (MRgFUS-MB) treatment, a radioenhancement therapy for breast cancer. METHODS AND FINDINGS: This prospective, single-center, single-arm Phase 1 clinical trial included patients with stages I-IV breast cancer with in situ tumours for whom breast or chest wall radiotherapy was deemed adequate by a multidisciplinary team (clinicaltrials.gov identifier: NCT04431674). Patients were excluded if they had contraindications for contrast-enhanced MR or microbubble administration. Patients underwent 2 to 3 MRgFUS-MB treatments throughout radiotherapy. An MR-coupled focussed ultrasound device operating at 800 kHz and 570 kPa peak negative pressure was used to sonicate intravenously administrated microbubbles within the MR-guided target volume. The primary outcome was acute toxicity per Common Terminology Criteria for Adverse Events (CTCAE) v5.0. Secondary outcomes were tumour response at 3 months and local control (LC). A total of 21 female patients presenting with 23 primary breast tumours were enrolled and allocated to intervention between August/2020 and November/2022. Three patients subsequently withdrew consent and, therefore, 18 patients with 20 tumours were included in the safety and LC analyses. Two patients died due to progressive metastatic disease before 3 months following treatment completion and were excluded from the tumour response analysis. The prescribed radiation doses were 20 Gy/5 fractions (40%, n = 8/20), 30 to 35 Gy/5 fractions (35%, n = 7/20), 30 to 40 Gy/10 fractions (15%, n = 3/20), and 66 Gy/33 fractions (10%, n = 2/20). The median follow-up was 9 months (range, 0.3 to 29). Radiation dermatitis was the most common acute toxicity (Grade 1 in 16/20, Grade 2 in 1/20, and Grade 3 in 2/20). One patient developed grade 1 allergic reaction possibly related to microbubbles administration. At 3 months, 18 tumours were evaluated for response: 9 exhibited complete response (50%, n = 9/18), 6 partial response (33%, n = 6/18), 2 stable disease (11%, n = 2/18), and 1 progressive disease (6%, n = 1/18). Further follow-up of responses indicated that the 6-, 12-, and 24-month LC rates were 94% (95% confidence interval [CI] [84%, 100%]), 88% (95% CI [75%, 100%]), and 76% (95% CI [54%, 100%]), respectively. The study's limitations include variable tumour sizes and dose fractionation regimens and the anticipated small sample size typical for a Phase 1 clinical trial. CONCLUSIONS: MRgFUS-MB is an innovative radioenhancement therapy associated with a safe profile, potentially promising responses, and durable LC. These results warrant validation in Phase 2 clinical trials. TRIAL REGISTRATION: clinicaltrials.gov, identifier NCT04431674.

Interventions for Concerning Patient-Reported Outcomes in Routine Cancer Care: A Systematic Review.

IMPORTANCE: Collecting patient-reported outcomes (PROs) in routine cancer care improves patient-clinician communication, decision making, and overall patient satisfaction. Recommendations exist regarding standardized ways to collect, store, and interpret PRO data. However, evidence on incorporating PROs into cancer process of care, especially the type of HIs that are warranted after observing a concerning PRO and the effectiveness of these HIs are lacking. OBJECTIVE: This study summarizes HIs triggered after PRO completion and their effectiveness in improving patient outcomes for adults being treated for cancer types that are resource intensive and associated with high symptom burden [i.e., gastrointestinal (GI), lung, and head and neck cancer (HNC)]. Secondary outcomes included factors associated with poor implementation of PROs. EVIDENCE REVIEW: A literature search of peer-reviewed publications on MEDLINE, CINAHL Plus, APA PsycInfo, Scopus, and Cochrane was conducted following PRISMA guidelines from 1 January 2012, to 31 July 2022. Trial and real-world studies describing HIs after PRO completion for adult patients being treated for GI, lung, and HNC were included. Sixteen studies involving 144,496 patients were included. The Joanna Briggs Institute critical appraisal checklist was used to assess risk of bias. FINDINGS: Of the 16 included studies, 5 included patients with HNC. Commonly used PRO measurement tools were the PRO-CTCAE and ESAS. Only three studies reported specific HIs delivered in response to concerning PROs and measured their effectiveness on patient outcomes. In all three studies, these HIs significantly improved cancer-related care. The most common HIs undertaken in response to concerning PROs were referrals to other specialists/allied healthcare professionals, medication changes, or self-management advice. Provider-related barriers to PRO measurement and delivery included the overwhelming number of alerts, the time required to address each PRO and the unclear role of healthcare providers in response to these alerts. Patient-related barriers included lower digital literacy and socioeconomic status, older age, rural living, and patients suffering from GI and HNC. CONCLUSIONS AND RELEVANCE: This review highlights that PRO-triggered HIs are heterogenous and can improve patient quality of life. Further studies are necessary to determine the types of interventions with the greatest impact on patient care and outcomes.

Stereotactic body radiotherapy for distant metastases to the head and neck.

PURPOSE: To report clinical outcomes for patients with metastatic disease to the head and neck (HN) treated with stereotactic body radiation therapy (SBRT). METHODS: A retrospective review of patients treated with SBRT to HN sites from 2012 to 2020 was conducted. Treatment indications included the following: oligometastases, oligoprogression, and control a dominant area of progression (DAP). Kaplan-Meier method was used to estimate local control (LC), regional control (RC), overall survival (OS), and progression-free survival (PFS). Univariable (UVA) and multivariable analyses (MVA) were performed. Grade 3-4 acute and late toxicities were reported by the Common Terminology Criteria for Adverse Events v5.0. RESULTS: Fifty-six patients (58 lesions) were analysed with a median follow-up of 16 months. Primary sites included lung (25.0%), kidney (19.6%), breast (19.6%) and other (35.8%). SBRT indications were as follows: oligometastases (42.9%), oligoprogression (19.6%) and local control of a dominant area of progression (37.5%). Most patients received SBRT to a single neck node (n = 47, 81.0%). Median SBRT dose was 40 Gy (range 25-50 Gy) in five fractions, with a median biologically effective dose (BED10) of 72 Gy (range 37.5-100 Gy). One- and 2-year LC and RC rates were 97.6% and 72.7% as well as 100% and 86.7%, respectively. Median OS was 19.2 months (95% [CI] 14.8-69.4), and median PFS was 7.4 months (95% [CI] 5.2-11.9). The 1-year OS and PFS rates for oligometastases, oligoprogression and DAP were 95.8%, 63.6% and 38.1% (p = 0.0039) as well as 56.5%, 27.3% and 19.1% (p = 0.0004), respectively. On MVA, treatment indication and histology were predictive for OS, while indication and prior systemic therapy were predictive for PFS. Cumulative late grade 3 + toxicity rate was 11.3%, without grade 5 events. CONCLUSION: The use of SBRT for metastatic disease to the HN provided excellent LC rates with low rates of regional failure and an acceptable toxicity profile, highlighting its utility in these patients. Patients with oligometastatic disease had better OS and PFS than others.

Patient-reported experience with the use of Mepitel Film for prevention of acute radiation dermatitis in breast cancer.

BACKGROUND AND PURPOSE: Mepitel Film (MF) has been demonstrated to reduce the severity of radiation dermatitis (RD) in patients receiving breast cancer radiotherapy (RT). The objective of this study was to characterize patient-reported experience with MF use, including its impact on daily activities and wellbeing. MATERIALS AND METHODS: This single-institution study analyzed anonymized responses to a questionnaire completed by patients who used MF for the prevention of RD during breast cancer RT. RESULTS: Of the 254 patients contacted, 192 patients completed the survey. Most patients disagreed or strongly disagreed that MF limited their ability to perform their daily activities, including household chores (88%, n = 169/191), their ability to work (83%, n = 157/189), or their ability to sleep (85%, n = 163/191). Furthermore, patients agreed or strongly agreed MF was comfortable on their skin (67%, n = 126/189) and protected their skin from rubbing against clothing (86%, n = 161/188). Some patients agreed or strongly agreed that MF affected their ability to shower (31%, n = 50/162), wear bras (28%, n = 51/185), and impacted their level of pruritus (35%, n = 67/189). However, most patients agreed or strongly agreed that their overall experience with MF was positive (92%, n = 173/189) and would recommend MF to a friend undergoing breast cancer RT (88%, n = 166/188). CONCLUSION: MF use is associated with positive patient-reported experience during breast RT with minimal impact on daily activities.

The protective role of postoperative radiation therapy in low and intermediate grade major salivary gland malignancies: A study of the Canadian Head and Neck Collaborative Research Initiative.

BACKGROUND: The objective of this study was to examine the utility of postoperative radiation for low and intermediate grade cancers of the parotid and submandibular glands. METHODS: The authors conducted a retrospective, Canadian-led, international, multi-institutional analysis of a patient cohort with low or intermediate grade salivary gland cancer of the parotid or submandibular gland who were treated from 2010 until 2020 with or without postoperative radiation therapy. A multivariable, marginal Cox proportional hazards regression analysis was performed to quantify the association between locoregional recurrence (LRR) and receipt of postoperative radiation therapy while accounting for patient-level factors and the clustering of patients by institution. RESULTS: In total, 621 patients across 14 tertiary care centers were included in the study; of these, 309 patients (49.8%) received postoperative radiation therapy. Tumor histologies included 182 (29.3%) acinic cell carcinomas, 312 (50.2%) mucoepidermoid carcinomas, and 137 (20.5%) other low or intermediate grade primary salivary gland carcinomas. Kaplan-Meier LRR-free survival at 10 years was 89.0% (95% confidence interval [CI], 84.9%-93.3%). In multivariable Cox regression analysis, postoperative radiation therapy was independently associated with a lower hazard of LRR (adjusted hazard ratio, 0.53; 95% CI, 0.29-0.97). The multivariable model estimated that the marginal probability of LRR within 10 years was 15.4% without radiation and 8.8% with radiation. The number needed to treat was 16 patients (95% CI, 14-18 patients). Radiation therapy had no benefit in patients who had early stage, low-grade salivary gland cancer without evidence of nodal disease and negative margins. CONCLUSIONS: Postoperative radiation therapy may reduce LLR in some low and intermediate grade salivary gland cancers with adverse features, but it had no benefit in patients who had early stage, low-grade salivary gland cancer with negative margins.

A comparison of acute patient-reported outcomes in breast cancer patients with and without regional nodal irradiation using the ESAS and PRFS tool.

BACKGROUND AND PURPOSE: Regional nodal irradiation (RNI) is commonly administered in patients with breast cancer with node-positive disease to prevent cancer recurrence. The purpose of this study is to identify whether RNI is associated with greater acute symptom burden from baseline to 1 to 3 months post completion of radiotherapy (RT) when compared to localized RT. MATERIALS AND METHODS: Patient and treatment characteristics were collected prospectively for breast cancer patients with and without RNI from February 2018 to September 2020. The Edmonton Symptom Assessment System (ESAS) and Patient-Reported Functional Status (PRFS) tool were completed by patients at baseline, weekly during RT, and at a 1- to 3-month follow-up visit. The Wilcoxon rank-sum or Fisher exact tests were used to compare variables between patients with or without RNI. RESULTS: A total of 781 patients were included in the analysis. Baseline symptom reporting was similar between cohorts, with the exception of PRFS scores (p = 0.0023), which were worse in patients receiving RNI. Across all time points, differences in outcomes between cohorts were minimal, except for lack of appetite (p = 0.03) and PRFS scores (p = 0.049), which were significantly aggravated in patients treated with RNI. CONCLUSION: There is insufficient evidence to suggest that RNI is associated with greater symptom burden as assessed with the ESAS. Further research should be conducted over a longer time period to determine the impact of late effects of RNI on patient-reported symptoms.

Comparison of neoadjuvant versus adjuvant chemotherapy for breast cancer patients prior to receiving radiation therapy using Edmonton Symptom assessment system (ESAS) scores.

BACKGROUND AND PURPOSE: Patients undergoing radiotherapy (RT) for breast cancer may receive adjuvant or neoadjuvant chemotherapy prior to the initiation of RT treatment. In the present study, baseline Edmonton Symptom Assessment System (ESAS) scores of patients who received neoadjuvant and adjuvant chemotherapy were collected prior to RT and compared to assess the association of each chemotherapy intent with pre-RT symptom burden. MATERIAL AND METHODS: The ESAS and Patient-Reported Functional Status (PRFS) tools were used to collect patient-reported symptoms at baseline. Patient and treatment-related factors were collected prospectively from February 2018 to September 2020. Univariate general linear regression analysis was applied to compare baseline scores between adjuvant and neoadjuvant chemotherapy patients. RESULTS: A total of 338 patients were included for analysis. Comparison of baseline ESAS scores revealed that patients who received adjuvant chemotherapy were more likely to report higher scores, reflecting higher symptom burden, compared to patients receiving neoadjuvant chemotherapy, including tiredness (p = 0.005), lack of appetite (p = 0.0005), shortness of breath (p < 0.0001), and PRFS (p = 0.012). CONCLUSION: This study suggests an association between patients who have received adjuvant chemotherapy for breast cancer and higher RT baseline ESAS scores when compared to patients who received neoadjuvant chemotherapy. Due to these findings, considerations should be made by healthcare providers of the symptom burden during RT for patients who receive adjuvant chemotherapy.

Mepitel film for the prevention and treatment of acute radiation dermatitis in breast cancer: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: This systematic review and meta-analysis aimed to evaluate the efficacy of Mepitel film in preventing or treating acute radiation dermatitis (RD) in patients with breast cancer in randomized controlled trials (RCTs). METHODS: Embase, APA PsychInfo, Journals@Ovid Full Text, Ovid MEDLINE, PubMed, and Cochrane Trials were searched until December 12, 2022, to identify RCTs on the use of Mepitel film for preventing or treating acute RD from breast cancer radiotherapy. Per-protocol analysis was used to compare outcomes, calculate pooled effect sizes, odds ratio (OR), and 95% confidence intervals (CI), and to create forest plots using random effects analysis in RevMan 5.4. RESULTS: Three RCTs were included in this review. Mepitel film significantly reduced the incidence of grade 3 RD (OR 0.15 95% CI 0.06, 0.37, p<0.0001) and grade 2 or 3 RD (OR 0.16 95% CI 0.04, 0.65, p=0.01) as scored on either the CTCAE or the RTOG scale. Additionally, Mepitel film significantly reduced RISRAS mean scores assessed by patients and combined researcher and patient (standardized mean difference (SMD) -7.59, 95% CI -14.42, -0.76, p=0.03; SMD -15.36, 95% CI -30.01, -0.71 p=0.04) but not the researcher component of the assessment tool (SMD -17.55, 95% CI -36.94, 1.84, p=0.08). CONCLUSION: Mepitel film reduced the incidence of acute RD and improved patient-reported outcomes with minimal side effects, the main one being itchiness. Future research should assess the feasibility of Mepitel film with respect to specific patient-reported outcomes such as health-related quality of life issues associated with its use.

Perceptions of healthcare professionals on the use of Mepitel Film for the prevention of acute radiation dermatitis in breast cancer.

INTRODUCTION: Randomized clinical trials support Mepitel Film (MF) as a prophylactic treatment for radiation dermatitis (RD) in patients undergoing breast radiotherapy. Although several studies have canvassed the opinion of patients on using MF, no such studies have been done to investigate the perception of healthcare professionals (HCPs). The objective of this study was therefore to investigate the perceptions of HCPs on MF as a treatment option for RD. METHODS: Anonymized responses to a web-based survey sent to HCPs at a single institution managing patients using MF during breast radiotherapy were analyzed. RESULTS: Of the 28 HCPs contacted, 22 completed the survey, including 6 radiation oncologists (ROs), 11 radiation therapists (RTTs), and 5 nurses. Most HCPs reported MF was better at preventing severe RD than the standard of care and improved radiation-induced skin reactions (n = 20/22, 91%, and n = 19/22, 86%, respectively). MF was recommended for mastectomy patients without reconstruction (n = 15/21, 71%). The majority of HCPs believed that patients' families could be trained to apply and remove MF (n = 19/22, 86%). Many HCPs perceived that implementation of MF would be difficult in terms of maintaining patient flow and wide-scale implementation within their institution (n = 11/22, 50%, and n = 10/22, 46%, respectively). Most HCPs perceived that fewer than 50% of their patients could afford MF if priced at $100 CAD (n = 15/20, 75%). CONCLUSION: These findings provide insights into the possibility of MF to be incorporated into standard practice of care for RD. Although most HCPs were satisfied with MF as a prophylactic treatment for RD, there are concerns about its resource-intensive operationalization and financial accessibility to patients. Future research should focus on ways to improve HCP experience with MF and to improve its implementation into clinical settings as standard of care.

Impact of adjuvant breast radiotherapy on patient-reported fatigue.

PURPOSE: Breast cancer patients receiving adjuvant radiotherapy (RT) benefit from local control. However, RT can give rise to increased fatigue, lowering quality of life. The aim of this study was to prospectively identify trends and risk factors in patient-reported fatigue associated with breast RT. MATERIAL AND METHODS: Patients were assessed using the Edmonton Symptom Assessment Scale (ESAS) before, once per week during RT, up to 6 weeks after RT completion, and 1-3 months post RT. Patients were included in the analysis if the ESAS was completed before, at least once during, and at least once after RT. RESULTS: A total of 651 patients were included. Fatigue scores increased significantly during weeks 1-3 (p < 0.001) and weeks 5-6 (p < 0.0001) during RT compared to baseline. After RT completion, fatigue scores did not change significantly compared to baseline. Mastectomy patients who received previous chemotherapy experienced significantly more fatigue compared to mastectomy patients without previous chemotherapy (p = 0.0002). Patients less than 50 (p = 0.002), 50-59 (p = 0.007), or 60-69 (p = 0.048) years of age at RT start were more likely to have higher proportions of moderate or severe fatigue compared to patients ≥ 70 years of age. CONCLUSIONS: Fatigue associated with breast irradiation increased up to 6 weeks during RT and returned to near baseline scores at 1-3 months post treatment. Given that fatigue was significant in mastectomy patients, further research is needed to reduce fatigue among this cohort, especially those who have received previous chemotherapy and younger patients who are receiving breast RT.

Prediction of breast cancer-related outcomes with the Edmonton Symptom Assessment Scale: A literature review.

PURPOSE: The Edmonton Symptom Assessment Scale (ESAS) is a validated tool used in patients with varied cancer diagnoses to measure patient symptoms. The present manuscript will review the literature assessing the ability of the ESAS to predict patient-related outcomes in breast cancer patients. METHODS: A literature search was conducted of Cochrane Central Register of Controlled Trials databases, Ovid MEDLINE, and Embase for English articles that investigated the use of predictive modelling with the ESAS in the breast cancer population. Study type, publication year, sample size, patient demographics, predicted outcomes, and strongest predictive factors/symptoms were summarized for each study. RESULTS: A total of nine articles were included in this review. Five articles used the ESAS in predictive models to determine patient time to death. ESAS was also used to predict emergency department visits, determine symptoms associated with decreased quality of life, and generate a Health Utility Score. Lack of appetite was the most common ESAS symptom, as it was reported in five studies to be associated with decreased survival. In four of the nine articles, an additional survey investigating physical functioning was used in combination with ESAS to strengthen the predictive models. CONCLUSIONS: Included studies support the use of ESAS in predictive models, particularly for predicting survival. Using the ESAS as a predictive tool allows for more accurate time to death predictions, potentially improving symptom management and preventing overtreatment of palliative patients near the end of life.

Radiation dermatitis assessment tools used in breast cancer: A systematic review of measurement properties.

PURPOSE: This review aimed to assess the quality and efficacy of tools currently used in breast cancer patients to score radiation dermatitis (RD), a common debilitating side effect of radiotherapy (RT). METHODS: A search was conducted through Ovid Medline, Embase, and Cochrane Central Register of Controlled Trials databases on 14 February 2020. English articles that evaluated an instrument's use in assessing RD among breast cancer patients receiving external beam RT were included. Studies that reported on the reliability, validity, or concordance of items between assessment tools were included in accordance with the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) criteria. RESULTS: Twelve studies were included in this review, with a total of 13 skin toxicity assessment tools discussed. Tools that assessed clinician-reported outcomes (CROs) mostly reported moderate correlation with biophysical parameter (BP) measurements and low correlation with patient-reported outcomes (PROs). Traditionally used CRO scoring tools demonstrated moderate inter-rater reliability between clinicians, likely due to the subjective nature of items on the grading scales. Most commonly used tools were found to be either insufficient or indeterminate in their measurement properties. CONCLUSIONS: Current standardized tools that measure CROs are subject to clinician interpretation and fail to represent the patient experience. Tools designed to assess PROs are promising in their assessments of the impact of RT on patient quality of life; however, most PRO tools are generic to all skin conditions and require further validation for use in breast cancer. Among tools that measure CROs, PROs, and BPs, there is insufficient evidence on their measurement properties to establish a "gold standard" for the assessment of RD in breast cancer patients.

Self-reported pain in breast cancer patients receiving adjuvant radiotherapy.

PURPOSE: Breast cancer patients receiving radiotherapy (RT) commonly report pain, contributing to physical and emotional distress, and potentially resulting in poor quality of life. This study prospectively identified trends and risk factors in patient-reported pain associated with breast irradiation using the Edmonton Symptom Assessment Scale (ESAS) and a study-specific Skin Symptom Assessment (SSA). METHODS: Before RT and once per week during RT, patients completed the ESAS and SSA. Upon RT completion, patients were contacted via telephone to complete both assessments weekly for 6 weeks, and a final assessment was conducted 1-3 months post-RT. Only data from patients who had completed both assessments before, at least once during, and at least once after RT were included in our analysis. RESULTS: A total of 426 patients provided data for the analysis. Overall acute pain increased significantly at week 1-2 (p < 0.0001), week 5 (p = 0.0011), and at 1-3 months (p < 0.0001) post-RT compared with baseline, and acute breast pain increased significantly at week 1 (p < 0.001) and week 2 (p = 0.0002) post-RT compared with baseline. Previous chemotherapy (adjuvant or neoadjuvant) in mastectomy patients was associated with increased overall pain compared with mastectomy patients without previous chemotherapy (p = 0.017). Younger patients (40-49 or 50-59 years of age) reported more overall pain (p = 0.0001, p = 0.038) and breast pain (p = 0.0003, p = 0.0038) compared with patients ≥ 60 years of age. CONCLUSIONS: Patient-reported pain associated with breast irradiation peaked 1 week after RT completion. Our findings provide support for closer monitoring of acute pain associated with breast RT in younger patients.

Metastasis to gastrostomy sites from upper aerodigestive tract malignancies: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Metastasis to the gastrostomy site in patients with upper aerodigestive tract (UADT) malignancies is a rare but devastating adverse event that has been poorly described. Our aim was to determine the overall incidence and clinicopathologic characteristics observed with development of gastrostomy site metastasis in patients with UADT cancers. METHODS: This was a systematic review and meta-analysis of 6138 studies retrieved from Medline, EMBASE, CINAHL, and the Cochrane Register after being queried for studies including gastrostomy site metastasis in patients with UADT malignancies. RESULTS: The final analysis included 121 studies. Pooled analysis showed an overall event rate gastrostomy site metastasis of .5% (95% confidence interval [CI], .4%-.7%). Subgroup analysis showed an event rate of .56% (95% CI, .40%-.79%) with the pull technique and .29% (95% CI, .15%-.55%) with the push technique. Clinicopathologic characteristics observed with gastrostomy site metastasis were late-stage disease (T3/T4) (57.8%), positive lymph node status (51.2%), and no evidence of systemic disease (M0) (62.8%) at initial presentation. The average time from gastrostomy placement to diagnosis of metastasis was 7.78 ± 4.9 months, average tumor size on detection was 4.65 cm (standard deviation, 2.02), and average length of survival was 7.26 months (standard deviation, 6.23). CONCLUSIONS: Gastrostomy site metastasis is a rare but serious adverse event that occurs at an overall rate of .5%, particularly in patients with advanced-stage disease, and is observed with a very poor prognosis. These findings emphasize a need for clinical practice guidelines to include a regular assessment of the PEG site and highlight the importance of detection and management of gastrostomy site metastasis by the multidisciplinary care oncology team.

Do patients enrolled in observational studies have better outcomes than non-participants? A retrospective analysis.

PURPOSE: Patients are commonly enrolled into clinical trials. It has been reported that these patients may have better outcomes than those not enrolled into the study. The reasoning from these improvements could be attributable to closer follow-up, better patient adherence, more health aware patients have, or reaction to observation such as the Hawthorne effect. METHODS: Three hundred forty-six patients were approached for a prospective skin toxicity study in adjuvant breast cancer radiotherapy (RT) but declined participation between January 2018 and July 2019 (non-trial group). They were retrospectively reviewed and patient, treatment and RT-related characteristics, as well as the occurrence of skin reactions, and the usage of topical treatments were collected. This was compared with a comparison cohort of 349 patients who were enrolled into a previously conducted prospective study (trial group). RESULTS: More patients in the trial group had conventional RT (CFRT) versus hypofractionated RT (HFRT). Data was further stratified and there was no significant difference in moist desquamation, topical antibiotic usage, dressing application, home care use, topical corticoid steroid use, and oral analgesic use. There was a significantly lower pain score in the group compared with the non-trial group in both HFRT and CFRT (OR = 0.091 and OR = 0.348, p < 0.0001). CONCLUSION: Our results demonstrated no differences other than pain between the trial group and non-trial group. Therefore, in this cohort, patients enrolled into an observational trial while undergoing adjuvant breast RT demonstrated similar experiences of skin reactions. There are challenges to assessing differences between these groups, as confounding is likely. Therefore, it is recommended for future studies to additionally assess the impact of study participation on outcomes such as quality of life, quality of care received, and/or anxiety levels.

Tissue segmentation-based electron density mapping for MR-only radiotherapy treatment planning of brain using conventional T1-weighted MR images.

PURPOSE: Magnetic resonance imaging (MRI) is the primary modality for targeting brain tumors in radiotherapy treatment planning (RTP). MRI is not directly used for dose calculation since image voxel intensities of MRI are not associated with EDs of tissues as those of computed tomography (CT). The purpose of the present study is to develop and evaluate a tissue segmentation-based method to generate a synthetic-CT (sCT) by mapping EDs to corresponding tissues using only T1-weighted MR images for MR-only RTP. METHODS: Air regions were contoured in several slices. Then, air, bone, brain, cerebrospinal fluid (CSF), and other soft tissues were automatically segmented with an in-house algorithm based on edge detection and anatomical information and relative intensity distribution. The intensities of voxels in each segmented tissue were mapped into their CT number range to generate a sCT. Twenty-five stereotactic radiosurgery and stereotactic ablative radiotherapy patients' T1-weighted MRI and coregistered CT images from two centers were retrospectively evaluated. The CT was used as ground truth. Distances between bone contours of the external skull of sCT and CT were measured. The mean error (ME) and mean absolute error (MAE) of electron density represented by standardized CT number was calculated in HU. RESULTS: The average distance between the contour of the external skull in sCT and the contour in coregistered CT is 1.0 ± 0.2 mm (mean ± 1SD). The ME and MAE differences for air, soft tissue and whole body voxels within external body contours are -4 HU/24 HU, 2 HU/26 HU, and -2 HU/125 HU, respectively. CONCLUSIONS: A MR-sCT generation technique was developed based on tissue segmentation and voxel-based tissue ED mapping. The generated sCT is comparable to real CT in terms of anatomical position of tissues and similarity to the ED assignment. This method provides a feasible method to generate sCT for MR-only radiotherapy treatment planning.

Survey of current practices from the International Stereotactic Body Radiotherapy Consortium (ISBRTC) for head and neck cancers.

AIM: To provide a multi-institutional description of current practices of stereotactic body radiotherapy (SBRT) for head and neck cancer. MATERIALS & METHODS: 15 international institutions with significant experience in head and neck SBRT were asked to complete a questionnaire covering clinical and technical factors. RESULTS: SBRT is used 10-100% of the time for recurrent primary head and neck cancer, and 0-10% of the time in newly diagnosed disease. Five centers use a constraint for primary disease of 3-5 cm and 25-30 cc. Nine institutions apply a clinical target volume expansion of 1-10 mm and 14 use a planning target volume margin of 1-5 mm. Fractionation regimens vary between 15 and 22 Gy in 1 fraction to 30-50 Gy in 5 or 6 fractions. The risk of carotid blowout quoted in the re-irradiation setting ranges from 3 to 20%. CONCLUSION: There is considerable heterogeneity in patient selection and techniques in head and neck SBRT practice among experienced centers.

Stereotactic body radiotherapy for head and neck cancer: an addition to the armamentarium against head and neck cancer.

In the recent years, stereotactic body radiation therapy (SBRT) has emerged as a potential therapy for head and neck malignancies. Although early results appear to be promising, serious acute and late effects have been observed, mainly in patients who have had prior external beam radiotherapy. This review will discuss the radiobiology of SBRT, clinical rationale and outcomes for SBRT in head and neck cancers and focus on the benefits and potential limitations in both de novo and re-irradiation settings.

Stereotactic Body Radiotherapy for Extracranial Oligometastatic Disease from Head and Neck Primary Cancers: A Systematic Review and Meta-Analysis.

INTRODUCTION: Stereotactic body radiotherapy (SBRT) is increasingly used to treat disease in the oligometastatic (OM) setting due to mounting evidence demonstrating its efficacy and safety. Given the low population representation in prospective studies, we performed a systematic review and meta-analysis of outcomes of HNC patients with extracranial OM disease treated with SBRT. METHODS: A systematic review was conducted with Cochrane, Medline, and Embase databases queried from inception to August 2022 for studies with extracranial OM HNC treated with stereotactic radiotherapy. Polymetastatic patients (>five lesions), mixed-primary cohorts failing to report HNC separately, lack of treatment to all lesions, nonquantitative endpoints, and other definitive treatments (surgery, conventional radiotherapy, and radioablation) were excluded. The meta-analysis examined the pooled effects of 12- and 24-month local control (LC) per lesion, progression-free survival (PFS), and overall survival (OS). Weighted random-effects were assessed using the DerSimonian and Laird method, with heterogeneity evaluated using the I2 statistic and Cochran Qtest. Forest plots were generated for each endpoint. RESULTS: Fifteen studies met the inclusion criteria (639 patients, 831 lesions), with twelve eligible for quantitative synthesis with common endpoints and sufficient reporting. Fourteen studies were retrospective, with a single prospective trial. Studies were small, with a median of 32 patients (range: 6-81) and 63 lesions (range: 6-126). The OM definition varied, with a maximum of two to five metastases, mixed synchronous and metachronous lesions, and a few studies including oligoprogressive lesions. The most common site of metastasis was the lung. Radiation was delivered in 1-10 fractions (20-70 Gy). The one-year LC (LC1), reported in 12 studies, was 86.9% (95% confidence interval [CI]: 79.3-91.9%). LC2 was 77.9% (95% CI: 66.4-86.3%), with heterogeneity across studies. PFS was reported in five studies, with a PFS1 of 43.0% (95% CI: 35.0-51.4%) and PFS2 of 23.9% (95% CI: 17.8-31.2%), with homogeneity across studies. OS was analyzed in nine studies, demonstrating an OS1 of 80.1% (95% CI: 74.2-85.0%) and OS2 of 60.7% (95% CI: 51.3-69.4%). Treatment was well tolerated with no reported grade 4 or 5 toxicities. Grade 3 toxicity rates were uniformly below 5% when reported. CONCLUSIONS: SBRT offers excellent LC and promising OS, with acceptable toxicities in OM HNC. Durable PFS remains rare, highlighting the need for effective local or systemic therapies in this population. Further investigations on concurrent and adjuvant therapies are warranted.