Baron J, Chelius M, Cohen L
… +14 more, Perez CC, Riina M, Ramesh S, Tierney A, Elghawy O, Hossain NM, Rook A, Villasenor-Park J, Samimi S, Kim E, Hubbeling H, Plastaras JP, Barta SK, LaRiviere M
PURPOSE: Low-dose total skin electron therapy (TSET) is an established treatment for diffuse cutaneous T-cell lymphoma. Although traditionally delivered using standard fractionation (STD-fx) schedules, hypofractionated (...PURPOSE: Low-dose total skin electron therapy (TSET) is an established treatment for diffuse cutaneous T-cell lymphoma. Although traditionally delivered using standard fractionation (STD-fx) schedules, hypofractionated (H-fx) regimens offer a practical, time-efficient alternative; however, comparative data remain limited. This study evaluated clinical responses, toxicity, and hematologic effects of H-fx versus STD-fx low-dose TSET. METHODS AND MATERIALS: We retrospectively analyzed 121 courses of low-dose TSET (12 Gy total) delivered to 111 patients with cutaneous T-cell lymphoma from 2015 to 2023. STD-fx was defined as 12 Gy in 6 fractions; H-fx included regimens of 12 Gy in 3 or 4 fractions. Acute toxicities were graded per the Common Terminology Criteria for Adverse Events v5.0 and categorized as "new or worsened" from baseline. Hematologic toxicity was assessed through serial complete blood counts. Overall survival and progression-free survival were measured from TSET completion to event or last follow-up; survival comparisons between regimens were exploratory. RESULTS: Of 121 TSET courses, 104 (86%) were STD-fx and 17 (14%) were H-fx. Median follow-up was 21 months overall and was shorter in H-fx (8 vs 22 months; P < .01). Eastern Cooperative Oncology Group 2 to 4 status was more frequent in H-fx (35% vs 13%; P = .03). Overall response rate (complete response + partial response) was 94% in both groups. At 24 months, overall survival was 87% for STD-fx versus 66.7% for H-fx (P = .13), and progression-free survival was 19% versus 17%, respectively (P = .59). New or worsened acute toxicities were common (98.1% vs 94.1%; P = .37) but mostly low-grade, with no grade 4 events. Rates of dermatitis were similar in STD-fx and H-fx groups (76.9% vs 76.5%), including high-grade events (12.5% vs 23.5%; P = .26). Cytopenias were prevalent at baseline and remained similar posttreatment, with no significant differences between regimens. CONCLUSIONS: H-fx low-dose TSET was feasible and demonstrated similar short-term response, acute toxicity, and hematologic effects as STD-fx, although long-term and comparative inferences are limited by the small H-fx cohort and short follow-up duration. In appropriately selected patients, abbreviated TSET regimens may be considered when shorter treatment courses are clinically indicated.
PURPOSE: This study evaluated the feasibility of involved-field irradiation (IFI) with a small margin (SM) in patients with esophageal squamous cell carcinoma (ESCC) undergoing neoadjuvant chemoradiotherapy. METHODS AND...PURPOSE: This study evaluated the feasibility of involved-field irradiation (IFI) with a small margin (SM) in patients with esophageal squamous cell carcinoma (ESCC) undergoing neoadjuvant chemoradiotherapy. METHODS AND MATERIALS: We retrospectively reviewed 511 patients with ESCC who underwent neoadjuvant chemoradiation therapy followed by radical esophagectomy between 2016 and 2022. The IFI was routinely applied. The clinical target volume was defined as the primary gross tumor volume plus a 2.0 to 3.0 cm longitudinal and 0.5 to 1.0 cm circumferential margin, and the nodal gross tumor volume plus a 0.5 to 1.0 cm margin, with modifications. Patients receiving a 2 cm longitudinal margin without further extension were classified as the SM group (n = 366); the others comprised the large-margin group. With radical esophagectomy, 3-field lymph node (LN) dissection was performed in 212 patients (41.5%), whereas 296 patients (57.9%) underwent 2-field LN dissection. Failure patterns, locoregional control, and survival outcomes were analyzed. Regional recurrence included LN defined by the American Joint Committee on Cancer eighth edition and supraclavicular nodes. RESULTS: During the median follow-up of 44.8 months, 213 patients (41.7%) experienced recurrence. First recurrences were locoregional recurrence (LRR) in 120 (23.5%), nonregional LN in 56 (11.0%), and distant metastases in 153 (29.9%) patients. Among LRR cases, 52 patients (10.2%) had infield failures, 28 (5.5%) had both infield and outfield failures, and 40 (7.8%) had outfield failures. Isolated outfield LRR occurred in only 17 patients (3.3%), of whom only 4 would have had their lesions covered by elective nodal irradiation. Locoregional control, progression-free survival, and overall survival did not differ between the SM and large-margin groups. CONCLUSIONS: IFI with SM demonstrated favorable outcomes and minimal isolated outfield recurrence, supporting its feasibility as a neoadjuvant setting for ESCC.
Liu Y, Goldrich N, Redmond KJ
… +23 more, Gabriel J, Zhou N, Swensen S, Skalina KA, Fekrmandi F, Vellayappan B, Guckenberger M, Foote M, Connell PP, Hsu CC, Vuong W, Gillespie EF, Tykodi SS, Nguyen TK, Mayerson JL, Nguyen QN, de Moraes FY, Siva S, Palmer JD, Kim M, Yang JT, Sahgal A, Lo SS
PURPOSE: Growing evidence supports stereotactic body radiation therapy (SBRT) over conventional radiation therapy for spine bone metastases, with an expanding role in non-spine bone metastases (NSBM). Our case-based revi...PURPOSE: Growing evidence supports stereotactic body radiation therapy (SBRT) over conventional radiation therapy for spine bone metastases, with an expanding role in non-spine bone metastases (NSBM). Our case-based review aims to inform radiation oncologists in the appropriate utilization of SBRT for representative cases of NSBM. METHODS AND MATERIALS: Three cases were selected for discussion: (1) rib, (2) skull base, and (3) femur. Relevant literature was reviewed, and areas for future investigation were discussed. RESULTS: SBRT can be effectively delivered in NSBM with appropriate patient selection, target volume delineation, prescription dose, organs at risk dose constraints, and treatment planning. CONCLUSIONS: The Radiosurgery Society's case-based review offers guidance on the appropriate use of SBRT in NSBM with discussions and consensus recommendations from experts. SBRT can be considered for an oligometastatic patient with favorable prognosis in whom the goal is durable local control and/or symptom relief. It can be considered for radioresistant histologies and improved OAR sparing. Available MRI or PET/CT should be fused to improve target volume delineation. A CTV margin, generally of 5 mm, should be considered to cover microscopic disease. As bones are easily visualized on daily images acquired for accurate and precise set-up of patients, a PTV margin should be kept less than or equal to 3 mm. While SBRT can be delivered in 1 fraction, fractionated SBRT may be preferred to meet dose constraints when the CTV is adjacent to the OARs. NSBM of long bones that are weight bearing, lytic, or have a high MIRELS score should be evaluated by an orthopedic surgeon.
PURPOSE: Spinal stereotactic body radiation therapy (SBRT) provides durable local control for metastatic spine disease but creates new demands for posttreatment surveillance, particularly in health care systems where mag...PURPOSE: Spinal stereotactic body radiation therapy (SBRT) provides durable local control for metastatic spine disease but creates new demands for posttreatment surveillance, particularly in health care systems where magnetic resonance imaging (MRI) access is limited. Existing guidelines recommend calendar-based imaging, which is challenging to implement in resource-constrained environments. We aimed to develop practical, risk-stratified follow-up guidelines for post-SBRT surveillance, grounded in real-world feasibility across province-wide oncology centers. METHODS AND MATERIALS: Seven radiation oncologists from 4 SBRT-providing centers (3 tertiary academic and 1 regional) participated in a structured, modified nominal group technique. Panelists reviewed the literature on imaging surveillance, contributed center-specific considerations, and iteratively refined recommendations. Nineteen candidate statements across 4 items were generated. Consensus thresholds were predefined as ≥80% ("strong"), 60% to 79% ("moderate"), and <60% ("no consensus"). RESULTS: In round 1, 11 of 19 statements achieved strong consensus, 5 were moderate, and 3 failed to meet the threshold. Following structured adjudication, word refinement, and 1 item removal, all 18 remaining statements achieved strong consensus in round 2. Key themes included were as follows: (1) anchoring imaging intensity to actionable clinical intent; (2) prioritizing early post-SBRT MRI only when salvage therapy is feasible; (3) de-escalating surveillance in low-risk or systemically progressing patients; (4) tailoring modality selection to resource availability; and (5) integrating tumor-specific considerations, including prostate cancer-specific pathways. The resulting framework replaced rigid schedules with risk-adapted intervals, emphasized clinical triggers and feasibility, and promoted thoughtful resource use. CONCLUSIONS: The consensus-derived guidelines present a pragmatic surveillance strategy for spine SBRT, calibrated to the realities of MRI access and clinical workflows. By embracing risk-adapted imaging, the framework reduces unnecessary investigations, preserves resources, and focuses surveillance where it is most likely to influence clinical outcomes. While rooted in the local context, the recommendations are broadly applicable to settings facing similar constraints. Prospective validation is warranted to evaluate oncologic and patient-reported outcomes under this de-escalated, resource-conscious model.
PURPOSE: Radiation dermatitis is among the most common adverse events associated with radiation therapy for early-stage glottic cancer. This study evaluated the effect of cutting out a portion of the thermoplastic mask o...PURPOSE: Radiation dermatitis is among the most common adverse events associated with radiation therapy for early-stage glottic cancer. This study evaluated the effect of cutting out a portion of the thermoplastic mask overlapping with the irradiation field on surface dose and investigated its benefit in reducing radiation dermatitis in patients with early-stage glottic cancer. METHODS AND MATERIALS: The surface dose on the anthropomorphic phantom with and without a thermoplastic mask was measured using Gafchromic EBT4 films (Ashland). The treatment plan was created with 2 opposed lateral fields, with a field size of 5.5 cm × 6.5 cm, and photon energies of 4 and 6 MV, produced by TrueBeam (Varian). For clinical investigation, we retrospectively reviewed patients with early-stage glottic cancer who received definitive radiation therapy between January 2008 and April 2024 at our institution. The inclusion criteria were clinical stages I and II, total irradiation dose of 60 Gy or more, and a 2-opposed lateral field technique employed for radiation therapy delivery. The incidence of radiation dermatitis in grades ≥2 and ≤1 was compared by age, clinical stage, radiation therapy fractionation, total dose, and cut-out thermoplastic mask using Fisher's exact test. P values less than .05 were considered statistically significant. RESULTS: The percentage increase in the surface dose by a thermoplastic mask was 47.1% for 4 MV and 59.4% for 6 MV. Fifty-nine patients were included in the clinical investigation. For the incidence of ≥grade 2 dermatitis, the only significant factor was the cut-out thermoplastic mask (41.7% with cut-out thermoplastic mask vs 74.5% without, P = .042). CONCLUSIONS: Cutting out the thermoplastic mask over the irradiation field reduced the surface dose by eliminating the bolus effect, thereby mitigating radiation dermatitis in patients with early-stage glottic cancer.
Zhang C, Mayo CS, Matrosic CK
… +15 more, Chang DT, Chng N, Dess RT, Evans JR, Gabryś D, Heron DE, Hoffmann L, Jackson WC, Matuszak MM, Prisciandaro JI, Rosen BS, Salerno KE, Simone CB, Xiao Y, Paradis KC
PURPOSE: To provide case-based, practical examples outlining step-by-step calculations and documentation for reirradiation (reRT) evaluation. The representative examples demonstrate the application of the Reirradiation C...PURPOSE: To provide case-based, practical examples outlining step-by-step calculations and documentation for reirradiation (reRT) evaluation. The representative examples demonstrate the application of the Reirradiation Collaborative Group (ReCOG) consensus for dosimetric assessment and reporting in reRT and illustrate how these standards can be implemented in clinical practice. METHODS AND MATERIALS: Two spine reRT cases were selected. Cumulative organ-at-risk doses were assessed using 3 approaches: direct point dose summation, point dose summation within overlap regions, and image registration-based 3-dimensional dose summation. Step-by-step calculations were performed for each approach, and new dose objectives for subsequent planning iterations were derived and compared. RESULTS: The example reRT cases detail the special medical physics consult process, highlighting different cumulative dose estimation strategies depending on the availability of voxel-based equieffective dose calculation and visualization tools. Selection of an assessment strategy should balance clinical resources with patient-specific considerations. Calculation and visualization of equieffective dose distributions facilitate cumulative dose assessment and strengthen image registration-based methods. If 3-dimensional equieffective dose calculation is not available, anatomically corresponding volumes and doses in each plan contributing to the cumulative dose in the areas of overlap can be determined manually to improve the accuracy of point dose-based summation. CONCLUSIONS: The case examples demonstrate how to apply the ReCOG consensus for dosimetric assessment and reporting in reRT and illustrate multiple strategies for cumulative dose evaluation. This work supports patient care and contributes to enhancing the field's knowledge and delivery of safer reRT.
Toya R, Kodaira T, Tamaki Y
… +13 more, Motegi A, Yamazaki T, Mizoguchi N, Kikuchi K, Tomita N, Tanaka O, Ishikawa K, Kosugi Y, Yasuda K, Saitoh JI, Murotani K, Ota Y, Akimoto T
PURPOSE: The palliative effects of the QUAD shot regimen were prospectively assessed using 3-dimensional conformal radiation therapy (3D-CRT) or intensity modulated radiation therapy (IMRT) for advanced head and neck squ...PURPOSE: The palliative effects of the QUAD shot regimen were prospectively assessed using 3-dimensional conformal radiation therapy (3D-CRT) or intensity modulated radiation therapy (IMRT) for advanced head and neck squamous cell carcinoma. METHODS AND MATERIALS: Fifty patients with stage III to IV head and neck squamous cell carcinoma were enrolled. One cycle consisted of 14 to 14.8 Gy in 4 fractions administered over 2 consecutive days and was repeated up to 3 cycles. Toxicity and quality of life (QOL) were assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0, and the University of Washington QOL Questionnaire, version 4, respectively. RESULTS: Two patients refused treatment prior to the initial cycle, whereas the remaining 48 were included in the analysis. 3D-CRT and IMRT were delivered to 16 (33%) and 32 (67%) patients, respectively. Thirty-nine (81%) patients completed all 3 cycles. Treatment response on physical examination was confirmed in 42 (88%) patients. Radiation therapy-associated grade 3 and 4 toxicities were observed in 4 (8%) and 1 (2%) patients, respectively. Of the 12 domain-specific QOL scores, >50% of patients reported the same or better status across all domains at 3 months. The global QOL scores were well preserved, with >70% of patients reporting the same or better scores, rising to >80% at 3 months. The median overall survival was 8.3 months. Multivariate analysis indicated that a T category < T4 (P = .001) and 3 QUAD shot cycles (P = .004) were significantly associated with improved overall survival. The median progression-free survival was 6.7 months. Multivariate analysis indicated that a T category < T4 (P = .026) and 3 QUAD shot cycles (P = .014) were significantly associated with improved progression-free survival. CONCLUSIONS: The QUAD shot regimen using 3D-CRT or IMRT achieves a high completion rate over 3 cycles, good palliative effects with lower toxicity, and improved or stable QOL. Three cycles are preferred for improved treatment outcomes.
PURPOSE: Clinical implementation of online adaptive radiation therapy (ART) requires new quality assurance methods and equipment. We introduce a novel quality assurance phantom designed to verify online ART treatment pla...PURPOSE: Clinical implementation of online adaptive radiation therapy (ART) requires new quality assurance methods and equipment. We introduce a novel quality assurance phantom designed to verify online ART treatment planning and delivery through practical, comprehensive end-to-end tests. Furthermore, we present the results of a multi-institutional validation of the phantom applied to cone beam computed tomography-guided online ART systems. METHODS AND MATERIALS: The phantom comprises swappable plastic pieces and features a rigid-yet-reconfigurable design to achieve multiple target morphologies with known geometric relationships. The phantom was circulated among 3 institutions. Each institution created 2 treatment plans based on shared dosimetric criteria. For each plan, online ART treatment sessions were conducted, and the plans were delivered to the phantom in multiple geometric configurations. Several treatment plan metrics (planning target volume V and D; organ-at-risk [OAR] D and D) were compared between the original and adaptive plans. Physical dose measurements were made in several locations using either plastic scintillators or an ion chamber, and 4 sessions were analyzed using film. Lastly, target volumes were contoured repeatedly by 3 separate users to estimate intrauser/interuser contouring variability. RESULTS: All 3 institutions used the phantom to test their online ART system's ability to adapt to changing target morphology. Across both plans, changes in target coverage metrics were small (95% of values ≤3.3%) and similar between original and adapted plans. However, changes in morphology increased OAR metrics by 20 to 60 cGy when using the original plan. Adapted plans did not increase dose to the OAR or compromise target coverage. The accurate delivery of the plans was confirmed with >97% of physical measurements ≤5% of their expected value and film gamma rates of 90.7% to 95.9%. Intrauser/interuser target volume variability was 1.0% to 1.7% and 1.3% to 2.4%, respectively. CONCLUSIONS: The phantom was successfully used at 3 separate institutions to verify the entire online ART treatment planning and delivery workflow.
PURPOSE: We assessed the utility of functional liver avoidance planning (FLAP) to meet clinical constraints and reduce dose to functioning liver tissue. METHODS AND MATERIALS: Twenty patients (aged 52-83 years, 6 women)...PURPOSE: We assessed the utility of functional liver avoidance planning (FLAP) to meet clinical constraints and reduce dose to functioning liver tissue. METHODS AND MATERIALS: Twenty patients (aged 52-83 years, 6 women) with varying degrees of cirrhosis (Child-Pugh [CP] scores A5-B9) underwent [99mTc] sulfur colloid single-photon emission computed tomography/computed tomography imaging with generation of functional liver volumes (FLV) at 30%max thresholds, and FLV were coregistered onto planning computed tomography scans. Half of the patients received prior liver-directed therapy (LDT). Volumetric modulated arc therapy-stereotactic body radiation therapy (SBRT) (5 fractions, 5 CP-A, 5 CP-B/C) conventional plans were optimized following American Society for Radiation Oncology consensus guidelines, and those that did not meet published functional liver dose constraints (FLV mean, FLV V20) were reoptimized for functional liver avoidance and scaled to the same target dose coverage. Scanning proton beam therapy (PBT) plans were similarly generated for hypofractionated regimens (15 fractions, 5 CP-A, 5 CP-B/C). We characterized the associations between clinical characteristics and the probability of FLAP reoptimization and correlations with FLV dose reduction. RESULTS: SBRT conventional plans for CP-A patients met all clinical and functional liver dose constraints, whereas 40% of CP-B/C SBRT plans, 40% of CP-A PBT plans, and 80% of CP-B/C PBT plans required reoptimization for FLV dose constraints. Compared with conventional plans, FLAP replans achieved a median reduction of 13% (range, 2%-30%) in FLV mean dose and 4% (range, 1%-10%) in FLV V20. Increasing likelihood of prior LDT correlated with a decrease in FLAP reoptimization frequency (Spearman R = -0.95, P = .05). This was reflected in CP-A SBRT patients requiring fewer functional liver avoidance replans (80% prior LDT, 0% FLAP replans) compared with CP-B/C PBT patients (10% prior LDT, 80% FLAP replans). CONCLUSIONS: We successfully investigated the clinical utility of functional tissue avoidance in different groups of patients with hepatocellular carcinoma as a planning strategy to preserve liver function and mitigate hepatoxicity.
PURPOSE: Maintaining adequate superficial dose coverage in breast volumetric modulated arc therapy (VMAT) remains challenging under interfractional motion and anatomic variation, largely due to the limited robustness of...PURPOSE: Maintaining adequate superficial dose coverage in breast volumetric modulated arc therapy (VMAT) remains challenging under interfractional motion and anatomic variation, largely due to the limited robustness of conventional skin flash strategies. This study evaluates the limitations of commonly used approaches and proposes a practical distributed virtual bolus strategy to improve motion robustness without dose escalation. METHODS AND MATERIALS: Six flash strategies-no flash, virtual target expansion with water- or air-equivalent density, and 3 virtual planning bolus configurations (single, dual, and triple)-were evaluated in 12 left-sided breast VMAT plans. The proposed triple virtual planning bolus strategy distributed discrete bolus segments along the anterior-lateral breast contour to maintain angular optimization support during arc delivery. Robustness was assessed using deformation-based motion simulations with displacements up to 15 mm. Superficial dose was evaluated using 3-mm and 5-mm skin shells, and target robustness was quantified using dose-volume metrics, relative coverage retention, and high-dose penalty reduction. RESULTS: All strategies achieved comparable nominal plan quality. Virtual target expansion with water-equivalent density produced the largest superficial hotspot burden and pronounced instability after density removal (planning clinical target volume 2 [PCTV2] V107%: 42.99% ± 11.57%). Conventional planning bolus strategies showed direction-dependent robustness loss under lateral and composite motion. In contrast, the triple virtual planning bolus strategy maintained stable superficial coverage across all simulated scenarios, preserving PCTV2 V95% above 97% for displacements up to 15 mm while reducing high-dose penalty by up to 56.59% relative to virtual target expansion. CONCLUSIONS: A distributed virtual bolus strategy enables motion-robust superficial dose delivery in breast VMAT while limiting high-dose escalation. This approach provides a practical and physics-informed solution for improving motion tolerance in arc-based breast radiation therapy without increasing planning complexity.
PURPOSE: This study aims to present single-institution workflows and experience for treating patients with implanted electronic devices (IEDs) at a high-volume proton pencil-beam scanning clinic. METHODS AND MATERIALS: A...PURPOSE: This study aims to present single-institution workflows and experience for treating patients with implanted electronic devices (IEDs) at a high-volume proton pencil-beam scanning clinic. METHODS AND MATERIALS: A multidisciplinary group was formed when opening the proton clinic to assess the risk of IEDs, primarily from neutron damage, and the potential for patient harm under device failure. A policy was developed for management of cardiac (CIEDs) and medical IEDs (MIEDs), including endocrinology devices, neurostimulators, auditory-assist devices, and infusion pumps. Patients treated with IEDs were assessed for trends and failures. RESULTS: A workflow was developed to identify devices and communicate potential action steps at 4 stages of treatment planning and delivery. Guidelines on-treatment beam selection and image guidance were shared between all device types. Patients with CIED received heart rate monitoring during each treatment and regular device interrogations, while guidance for MIEDs varied by function and risk of harm. A total of 294 proton radiation therapy courses were delivered to patients with IEDs. Of 144 courses delivered to patients with CIED devices, 5 had recoverable resets with no major failures. CONCLUSIONS: Risk-based guidelines were developed and refined to safely treat patients' CIEDs and MIEDs.
Long-term survival after glioblastoma (GB) remains uncommon; however, advances in genomic research and contemporary multimodal therapy have increased the number of long-term survivors. In these patients, late effects of...Long-term survival after glioblastoma (GB) remains uncommon; however, advances in genomic research and contemporary multimodal therapy have increased the number of long-term survivors. In these patients, late effects of cranial radiation therapy may accumulate over time, affecting cognitive and endocrine function and increasing the risk of cerebrovascular disorders and secondary malignancies. We report a long-term GB survivor who developed multiple late radiation-related complications, including radiation-induced intracranial aneurysm (RIA). During the clinical course of this case, serial imaging demonstrated that hemodynamic stress secondary to proximal large-artery stenosis/occlusion contributed to aneurysm formation. This observation suggests that cerebrovascular risk after cranial irradiation cannot be assessed solely on the basis of radiation dose distribution and that hemodynamic stress may play a contributory role in RIA development. This case highlights 2 important clinical implications. First, late radiation-related complications may accumulate in the same long-term GB survivor and become critical determinants of outcome. Second, cerebrovascular risk cannot be assessed based on radiation dose distribution alone, and the effects of hemodynamic stress should be considered. With advances in genomics and contemporary care increasing the number of long-term survivors, the incidence of postradiation therapy complications is likely to rise. To reduce preventable morbidity, surveillance should extend beyond tumor control to include longitudinal vascular assessment, with explicit attention to hemodynamic warning signs, such as new arterial stenoses, evolving collateral pathways, and de novo or enlarging aneurysms.
PURPOSE: Brachytherapy is an integral part of cervical cancer management. In interstitial brachytherapy, image guided needle insertion can be logistically challenging in resource-limited settings. This study aimed to eva...PURPOSE: Brachytherapy is an integral part of cervical cancer management. In interstitial brachytherapy, image guided needle insertion can be logistically challenging in resource-limited settings. This study aimed to evaluate whether a fixed-configuration (FC) needle insertion method yields dosimetric results and toxicity profile comparable to the standard, image guided technique. METHODS AND MATERIALS: The study included cervical cancer patients, FIGO IB2-IVa, who underwent external beam radiation (EBRT) followed by interstitial brachytherapy, 28Gy/4 fractions, via Utrecht applicator. Patients were either assigned to an FC group, where 6 lateral needles were inserted at 2 cm depth without image guidance, or the standard of care (SOC) group, where CT guided needle insertion was done. Cross-over was permitted if needed. Planning a CT scan was done afterward in both groups. Per patient, dosimetric analysis was done in patients with a consistent technique throughout treatment. The dosimetric parameters for HR CTV D90 and organs at risk (OARs), that is, D2cc of bladder, rectum, and sigmoid colon, were analyzed and compared using Mann-Whitney U test. Patients were evaluated for posttreatment acute toxicity. RESULTS: 181 fractions were evaluated in a cohort of 46 patients. Per-fraction analysis (FC = 93, SOC = 88) revealed insignificant differences across HRCTV (P = .28), D2cc bladder (P = .98), and D2cc rectum (P = .37). D2cc sigmoid was significantly greater in the FC group (median D2cc = 4.79 Gy) than the SOC group (median D2cc = 4.36 Gy, P = .01). Per-patient analysis (FC = 17, SOC = 14) yielded insignificant dosimetric differences across the clinical target volume (P = .57), D2cc bladder (P = .440), D2cc rectum (P = .54), and D2cc sigmoid (P = .52). No patient in either group developed grade CTCAE 3-4 OAR toxicity. CONCLUSIONS: The FC needle insertion method is a clinically feasible option in cervical brachytherapy, yielding minimal toxicity and dosimetric outcomes comparable to the standard, image guided approach, thus offering a viable alternative that can reduce health care burden, especially in resource-limited settings.
PURPOSE: The recently published results of the National Surgical Adjuvant Breast and Bowel Project B51 trial suggest that regional nodal irradiation may be safely omitted in patients with cT1-3N1 breast cancer treated wi...PURPOSE: The recently published results of the National Surgical Adjuvant Breast and Bowel Project B51 trial suggest that regional nodal irradiation may be safely omitted in patients with cT1-3N1 breast cancer treated with either lumpectomy or mastectomy, and achieve a pathologic complete response (pCR) in the regional nodes. Of note, almost 80% of patients on the trial demonstrated breast pCR. The goal of our study was to compare clinical outcomes between patients with breast pCR versus not. METHODS AND MATERIALS: We included all patients treated at a single institution between 2010 and 2021 with cT1-3N1 breast cancer (pathologically proven via fine needle aspiration) who completed neoadjuvant chemotherapy and had axillary nodal pCR. Patients could undergo breast-conserving surgery or mastectomy. Univariate and multivariate logistic models were used to identify factors associated with breast pCR. Cox proportional hazard model was used to find independent prognostic variables associated with disease-free survival (DFS). RESULTS: We identified 124 patients meeting eligibility criteria. Of those, 72 patients (58%) achieved a breast pCR. On multivariate analysis, patients with human epidermal growth factor receptor (HER2)-positive breast cancer were more likely to develop breast pCR than patients with HER2-negative disease (odds ratio = 15.3; CI, 2.9-156.6; P = .001). At a median follow-up of 5 years, our study showed an overall low rate of local recurrence or distant metastasis with 5-year DFS of 92.3%. There was a numerically higher disease recurrence rate in patients without a breast pCR compared to those with a breast pCR, though this difference was not statistically significant (4.2% vs 12%; hazard ratio = 3.41; 95% CI, 0.53-22.1; P = .2). CONCLUSIONS: Our study showed that of the 124 patients who had pCR in the nodes, only 58% had a pCR in the breast, which is lower than the 80% rate seen in National Surgical Adjuvant Breast and Bowel Project B51. While our study found no significant difference in 5-year DFS between those with breast pCR versus not, given that patients with ER/PR+/HER2- disease are less likely to achieve breast pCR and tend to recur at later timepoints, further research is needed to evaluate the benefit of regional nodal irradiation in patients with a pCR in the axilla without a pCR in the breast.
PURPOSE: Incorporating Cherenkov imaging can improve radiation therapy treatment verification through both real-time monitoring and retrospective analysis of beam delivery. In bilateral breast radiation therapy, a medial...PURPOSE: Incorporating Cherenkov imaging can improve radiation therapy treatment verification through both real-time monitoring and retrospective analysis of beam delivery. In bilateral breast radiation therapy, a medial gap between opposing beams is intentionally planned to avoid unwanted overlap in the midline region. We present the first in vivo analysis of Cherenkov images from bilateral breast radiation therapy. METHODS AND MATERIALS: All patients were treated with a single-isocenter, 3-dimensional conformal plan using a deep-inspiration breath-hold technique. Cherenkov emissions were recorded with a ceiling-mounted camera. Optical phantom experiments were conducted to identify an appropriate imaging thresholding method. The minimum distance across the medial gap was measured using the Cherenkov imaging data for 3 patients recorded across a total of 23 treatment fractions. RESULTS: Analysis of the Cherenkov beam footprints demonstrated a discernible gap for all delivered fractions. The average minimum gap size computed in each of the patient treatment plans was 1.1 cm, 1.0 cm, and 2.0 cm. The average minimum gap size for each patient during radiation therapy measured with Cherenkov imaging was 1.0 ± 0.4 cm, 0.9 ± 0.2 cm, and 2.0 ± 0.6 cm, respectively. Intrapatient gap size variability is thought to be because of patient breath-hold differences across sessions. CONCLUSIONS: This study provides the use of Cherenkov imaging to verify the daily medial field gap in bilateral breast radiation therapy patients. Regular offline review of these images could enable direct feedback to the treatment team in cases of potential field overlap, while also reducing the need for radiochromic film or detector-based in vivo dosimetry.