Received Radiation Therapy Research Articles

Abstract A081: Real-world treatment patterns and clinical outcomes in patients with HER2+ metastatic breast cancer receiving systemic therapy in Ontario, Canada

Abstract Background: Real-world data on treatment patterns and prevalence of brain metastases in patients with HER2+ metastatic breast cancer (mBC) are limited. This study described treatment patterns and clinical outcomes among patients with HER2+ mBC in Canada. Methods: This was a retrospective chart review of adult patients diagnosed with de-novo or recurrent HER2+ mBC between Jan 1, 2014 and Mar 1, 2021 (prior to wide availability of new treatments) at Sunnybrook Research Institute and Sinai Health, two large BC treatment centres in Canada. Data on patient characteristics and treatment regimens were extracted. Treatment patterns, time to next treatment (TTNT; as a proxy for progression-free survival), and presence of brain metastases were assessed in the first-line (1L), second-line (2L), and third-line (3L) settings. TTNT analyses used Kaplan-Meier methodology to account for censoring. Results: Of 121 patients with HER2+ mBC, the median (IQR) age was 54.0 (17.0) years. 38.0% of patients had de-novo disease and 62.0% had recurrent mBC; 12 (9.9%) had brain metastases at the time of mBC diagnosis. Systemic therapies generally aligned with Canadian funded regimens for 1L (101 of 121 patients [83.5%] received trastuzumab + pertuzumab ± chemotherapy ± subsequent endocrine therapy; 8/121 [6.6%] received endocrine therapy only) and 2L (50/68 [73.5%] received T-DM1 ± endocrine therapy; 9/68 [13.2%] received endocrine therapy only). However, treatment patterns were heterogeneous in the 3L setting (14/46 [30.4%] received anti-HER2 TKI + chemotherapy ± trastuzumab; 10/46 [21.7%] received endocrine therapy only; 10/46 [21.7%] received chemotherapy). Median (95% CI) TTNT in months was 21.4 (16.1, 27.2) in 1L, 11.0 (8.5, 16.5) in 2L, and 8.7 (5.4, 15.6) in 3L. Median (IQR) follow-up was 29.9 (25.2) months. In total, 57 patients (47.1%) were diagnosed with brain metastases during the study period (17 pre-1L, 24 post-1L/pre-2L, 6 post-2L/pre-3L) and of these, 73.7% received radiation therapy. Conclusions: In patients with HER2+ mBC in Canada, 3L treatment patterns are heterogeneous, median TTNT is <1 year, and almost half develop brain metastases. These data from two large treating centres in Ontario suggest a high unmet need for more effective treatment regimens in later lines of therapy, particularly 3L, for patients with HER2+ mBC. Citation Format: Katarzyna J Jerzak, Ruth Moulson, Ling-I Hsu, Chris Lenhu, Dhivo Krishnathasan, Jessica Weiss, Christine Brezden-Masley. Real-world treatment patterns and clinical outcomes in patients with HER2+ metastatic breast cancer receiving systemic therapy in Ontario, Canada [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A081.

Protocol for Evaluating the Efficacy and Safety of Radiotherapy for Prostate and Oligometastatic Lesions in Patients With Low-Burden Sensitive Oligometastatic Prostate Cancer: An Open, Exploratory Pilot Clinical Trial.

The existing large prospective study demonstrates the benefits of primary radiotherapy in patients with low-volume oligometastatic prostate cancer (OMPC), and there is additional evidence of the benefits of local metastasis-directed therapy (MDT) for metastatic lesions. However, there are no results from a prospective study to demonstrate the efficacy of radiotherapy for prostate and oligometastases. Therefore, the aim of the protocol is to illustrate the efficacy of radiotherapy for prostate and oligometastatic lesions in patients with low-volume de novo hormone-sensitive OMPC. This study involves a prospective, single-center, limited-sample, single-arm exploration of radiotherapy for prostate and oligometastatic lesions in patients diagnosed with low-volume hormone-sensitive OMPC. Eligible participants undergo thorough assessments and treatment involving endocrine therapy alongside radiation targeting metastatic lesions and the pelvic region. The primary site is treated with volumetric modulated arc therapy (VMAT), while metastatic sites are treated with either VMAT or stereotactic body radiation therapy (SBRT) depending on their location. All patients received radiation therapy for both the primary and metastatic lesions combined with endocrine therapy. Endocrine therapy with an antiandrogen (bicalutamide, for 4 weeks) androgen deprivation therapy combined with novel hormonal agents (acetate abiraterone) will be continued for 2 years. The primary objective is to evaluate progression-free survival-2 (PFS-2), while secondary endpoints include androgen deprivation therapy (ADT)-free survival, quality of life (QoL), overall survival, time to castration-resistant prostate cancer (CRPC), radiation-related complications, and endocrine therapy-related adverse events. Approval was obtained from the ethics committee of the First Affiliated Hospital of Naval Medical University (CHEC2023-220). This is a single-arm exploration pilot trial evaluating radiotherapy for prostate and oligometastatic lesions in patients with OMPC. It aims to disseminate its findings through peer-reviewed journals and relevant medical conferences, with the intention of publication and presentation at these events. Clinicaltrials.gov identifier NCT06198387.

Edge roughness quantifies impact of physician variation on training and performance of deep learning auto-segmentation models for the esophagus

Manual segmentation of tumors and organs-at-risk (OAR) in 3D imaging for radiation-therapy planning is time-consuming and subject to variation between different observers. Artificial intelligence (AI) can assist with segmentation, but challenges exist in ensuring high-quality segmentation, especially for small, variable structures, such as the esophagus. We investigated the effect of variation in segmentation quality and style of physicians for training deep-learning models for esophagus segmentation and proposed a new metric, edge roughness, for evaluating/quantifying slice-to-slice inconsistency. This study includes a real-world cohort of 394 patients who each received radiation therapy (mainly for lung cancer). Segmentation of the esophagus was performed by 8 physicians as part of routine clinical care. We evaluated manual segmentation by comparing the length and edge roughness of segmentations among physicians to analyze inconsistencies. We trained eight multiple- and individual-physician segmentation models in total, based on U-Net architectures and residual backbones. We used the volumetric Dice coefficient to measure the performance for each model. We proposed a metric, edge roughness, to quantify the shift of segmentation among adjacent slices by calculating the curvature of edges of the 2D sagittal- and coronal-view projections. The auto-segmentation model trained on multiple physicians (MD1-7) achieved the highest mean Dice of 73.7 ± 14.8%. The individual-physician model (MD7) with the highest edge roughness (mean ± SD: 0.106 ± 0.016) demonstrated significantly lower volumetric Dice for test cases compared with other individual models (MD7: 58.5 ± 15.8%, MD6: 67.1 ± 16.8%, p < 0.001). A multiple-physician model trained after removing the MD7 data resulted in fewer outliers (e.g., Dice ≤ 40%: 4 cases for MD1-6, 7 cases for MD1-7, Ntotal = 394). While we initially detected this pattern in a single clinician, we validated the edge roughness metric across the entire dataset. The model trained with the lowest-quantile edge roughness (MDER-Q1, Ntrain = 62) achieved significantly higher Dice (Ntest = 270) than the model trained with the highest-quantile ones (MDER-Q4, Ntrain = 62) (MDER-Q1: 67.8 ± 14.8%, MDER-Q4: 62.8 ± 15.7%, p < 0.001). This study demonstrates that there is significant variation in style and quality in manual segmentations in clinical care, and that training AI auto-segmentation algorithms from real-world, clinical datasets may result in unexpectedly under-performing algorithms with the inclusion of outliers. Importantly, this study provides a novel evaluation metric, edge roughness, to quantify physician variation in segmentation which will allow developers to filter clinical training data to optimize model performance.

Рецидивирующий афтозный стоматит: ребамипид – новое направление в лечении и профилактике

Recurrent aphthous stomatitis (RAS) is a widespread disease worldwide, accompanied by the appearance of painful aphthae on the oral mucosa. RAS is a multifactorial disease. Local and systemic factors such as trauma, food sensitivities, nutritional deficiencies, systemic conditions, immunological disorders and genetic polymorphisms are associated with its development. Studies examining the possible connection between the development of RAS and Helicobacter pylori infection are reviewed. The review examined publications on the use of the universal gastro- and enteroprotector rebamipide as a new direction in the treatment and prevention of RAS. Clinical data clearly establish the safety and effectiveness of rebamipide in the treatment of RAS and Behçet's disease. The benefits of rebamipide for RAS include: reduced pain duration, accelerated healing and reduced relapse rates. Aphthous stomatitis (oral mucositis) can be induced by chemotherapy and radiation therapy in oncology practice, with an incidence reaching 100% in patients receiving high-dose chemotherapy and up to 80% of patients receiving radiation therapy. A number of studies in its treatment and prevention have also demonstrated the effectiveness and safety of systemic and local use of rebamipide. The presented review expands the scope of rebamipide, suggesting the possibility of its use in dental and oncological practice for the treatment and prevention of RAS, including Behcet's disease, and oral mucositis.

Oral health in cancer palliative care: cross-sectional study

ObjectivesPatients on anticancer therapy attending palliative care services often have oral health problems, but not enough is known in this regard (in India). This cross-sectional study aimed to elucidate this...

Pulmonary metastatectomy in pediatric cancer patients at National Cancer Institute, Egypt: prognostic factors and outcome

BackgroundMetastatic tumors account for 80% of all lung tumors in children. Wilms tumour and osteosarcoma are the most tumors of childhood that produce lung metastases. The aim of the current study is to assess the prognostic factors of pulmonary metastatectomy in pediatric solid tumours as age, number, size, site,laterality, resectability of pulmonary nodules, and number of Thoracotomies. Calculate overall survival among patients who underwent pulmonary metastatectomy.MethodsIt is a retrospective study including all pediatric patients with metastatic solid tumors to lungs treated at pediatric oncology department, National Cancer Institute, Cairo University from 2008 to 2014. Fifty-five patients were included, 43 (78.2℅) patients of them had Osteosarcoma.ResultsThirty (54.5℅)patients were male. The mean age was 15 years ranging from (4.5- 23) years. The site of primary disease was at lower limbs in 43 (78.2%) patients. All patients underwent complete surgical resection of the primary disease with negative margin, 22(51.1%) of the osteosarcoma patients did amputation with tumor necrosis less than 90%. All patients received chemotherapy and only 9 received radiation therapy. The patients were classified into four groups according to time of diagnosis of pulmonary metastasis: at time of diagnosis in 13 (21.8%) patients, within treatment in 16 (30.9%) patients, within first year follow up in 18 (32.7%) patients and detected late in 8 (14.5%) patients. Bilateral lung metastasis diagnosed by CT chest were detected in 42 (76.4%) patients. Size of metastatic nodules was ranging from (0.5 to 10 cm) with mean 3.4 cm. Number of metastatic nodules was ranging from (1 to 28) median 4.Metastatic complications were detected in 19 patients. 5-year OS was 74.8% in the study group, and 68% in osteosarcoma patients. Effect of prognostic factors as sex, time of respectability, laterality, tumor necrosis of the 1ry disease, Timing of lung metastasis, size and site of the primary, Surgical approach of metastatectomy, postoperative complications on overall survival of the studied patients was done with significant P-value of tumor necrosis of the 1ry disease and Timing of lung metastasis 0.017, 0.001 respectively.ConclusionResection of pulmonary metastases of pediatric solid tumours is a safe and effective treatment that offers better survival.

The effect of germline DNA repair mutations on radiosensitivity in pancreatic ductal adenocarcinoma.

703 Background: The association between homologous recombination deficiency (HRD) in pancreatic ductal adenocarcinoma (PDAC) and sensitivity to platinum-based chemotherapy highlights the need to further understand how germline DNA repair mutations influence the efficacy of different therapies. Given the recent ALLIANCE data that chemotherapy alone is an acceptable standard of care to enhance R0 resection, the focus has shifted towards the contribution of radiotherapy. However, the relationship between germline DNA repair mutations in general and radiosensitivity remains less understood. This study explores the relationship between germline mutations and the Radiosensitivity Index (RSI) gene signature. Methods: After obtaining institutional review board approval, a retrospective analysis was performed of patients who had both RSI and germline mutation testing (i.e., BRCA1, BRCA2, BLM, ATM, MLH1, MSH2, MSH6, PMS2, and BARD mutations) between 1999 and 2023 at a single institution. Student T, Chi squared, Kaplan Meier (KM), Cox univariate log regression (UVA), and Mann-Whitney U (MWU) tests were used for statistical analyses. Results: A total of 25 patients were included, 13 with mutations and 12 without. MWU analysis demonstrated a significant difference in RSI values, where patients with mutations exhibited greater radiosensitivity (mean 0.379 vs. 0.464, p=0.040). The median age at diagnosis, max diameter of tumor, and baseline CA 19-9 were 67 years (range 47 – 77), 3.4 cm (range 0.8 – 8.2), and 288 (9.5 – 26,100), respectively. Most of the tumors were resectable (84%), stage IIB (36%), and grade 2 (68%). All patients underwent resection, with the majority without neoadjuvant therapy (96%). Most patients received chemotherapy (n=18; 72%), most commonly gemcitabine monotherapy (n=14/18). A majority also received radiation therapy (n=15; 60%), with 93% receiving chemoradiation (n=14/15). The median follow-up was 20.8 months. KM analysis yielded a median overall survival (OS) of 20.0 months (95% CI: 7.1-33.0) and progression-free survival (PFS) of 15.1 months (95% CI: 12.3-18.0) for the entire cohort. At the time of analysis, 15.4% of patients with mutations were alive (&gt;10 years), compared to none without mutations (p=0.157). There were no statistically significant differences between the two cohorts for clinical outcomes on KM analysis. On UVA, worse OS was correlated with stage III (HR 7.9, 95% CI 1.2 – 50.2) and IV (HR 11.8, 95% CI 1.4 – 102.3). No other variables were associated with OS on UVA or on mutant-only subgroup analysis. Conclusions: Our findings demonstrate an increased radiosensitivity in patients with germline DNA repair mutations, suggesting these cancers might be more susceptible to radiation-induced DNA damage. Since our results are constrained by the small sample size, further studies are needed to understand the relationship between PDAC with DNA repair mutations.

TRIP13 Enhances Radioresistance of Lung Adenocarcinoma Cells through the Homologous Recombination Pathway

Radiation therapy is one of the most common treatments for non-small cell lung cancer (NSCLC). However, the insensitivity of some tumor cells to radiation is one of the major reasons for the poor efficacy of radiotherapy and the poor prognosis of patients, and exploring the underlying mechanisms behind radioresistance is the key to solving this clinical challenge. This study aimed to identify the molecules associated with radioresistance in lung adenocarcinoma (LUAD), identified thyroid hormone receptor interactor 13 (TRIP13) as the main target initially, and explored whether TRIP13 is related to radioresistance in LUAD and the specific mechanism, with the aim of providing theoretical basis and potential targets for the combination therapy of LUAD patients receiving radiotherapy in the clinic. Three datasets, GSE18842, GSE19188 and GSE33532, were selected from the Gene Expression Omnibus (GEO) database and screened for differentially expressed genes (|log FC|>1.5, P<0.05) in each of the three datasets using the R 4.1.3 software, and then Venn diagram was used to find out the differentially expressed genes common to the three datasets. The screened differential genes were then subjected to protein-protein interaction (PPI) analysis and module analysis with the help of STRING online tool and Cytoscape software, and survival prognosis analysis was performed for each gene with the help of Kaplan-Meier Plotter database, and the TRIP13 gene was identified as the main molecule for subsequent studies. Subsequently, the human LUAD cell line H292 was irradiated with multiple X-rays using a sub-lethal dose irradiation method to construct a radioresistant cell line, H292DR. The radioresistance of H292DR cells was verified using cell counting kit-8 (CCK-8) assay and clone formation assay. The expression levels of TRIP13 in H292 and H292DR cells were measured by Western blot. Small interfering RNA (siRNA) was used to silence the expression of TRIP13 in H292DR cells and Western blot assay was performed. The clone formation ability and migration ability of H292DR cells were observed after TRIP13 silencing, followed by the detection of changes in the expression levels of proteins closely related to homologous recombination, such as ataxia telangiectasia mutated (ATM) protein. Screening of multiple GEO datasets, validation of external datasets and survival analysis revealed that TRIP13 was highly expressed in LUAD and was associated with poor prognosis in LUAD patients who had received radiation therapy. And the results of gene set enrichment analysis (GSEA) of TRIP13 suggested that TRIP13 might be closely associated with LUAD radioresistance by promoting homologous recombination repair after radiation therapy. Experimentally, TRIP13 expression was found to be upregulated in H292DR, and silencing of TRIP13 was able to increase the sensitivity of H292DR cells to radiation. TRIP13 is associated with poor prognosis in LUAD patients treated with radiation, possibly by promoting a homologous recombination repair pathway to mediate resistance of LUAD cells to radiation.

Abstract B002: Phase I study of endoscopic ultrasound (EUS)-guided NBTXR3 delivery activated by radiotherapy (RT) for locally advanced or borderline resectable pancreatic cancer (LAPC or BRPC)

Abstract Patients with LAPC or BRPC often receive radiation therapy (RT) after chemotherapy (chemo) if no metastatic progression has occurred. Historically, CA19-9 normalizes in ~20 to 30% of patients after all therapy. While escalated dose radiotherapy (EDR) has shown promising survival in selected patients, extending use of EDR to all patients is challenging due to RT dose limitations of the bowel. To overcome this limitation, we are investigating NBTXR3, composed of functionalized hafnium oxide nanoparticles administered by a single intratumoral injection, locally amplifying the RT dose. In this phase 1 trial, the primary objective is to determine the NBTXR3 recommended phase 2 dose (RP2D). Secondary objectives are to measure anti-tumor effects. The study uses a Bayesian optimal interval design (BOIN) and has two parts: dose-finding (NBTXR3 at [level 1] 33% of gross tumor volume [GTV] or [level 2] at 42% of GTV) and cohort expansion at RP2D. In part 1, eligibility criteria included only LAPC patients with no evidence of metastatic disease after 2-6 months of chemo, part 2 allows BRPC. NBTXR3 was administered once prior to RT via an EUS-guided intratumoral injection. All patients received 45 Gy in 15 fractions with intensity modulated radiation therapy (IMRT). Patients were followed up to 1 year. Dose-limiting toxicities (DLTs) were defined as any grade ≥ 3 adverse events definitely or possibly related to NBTXR3 and/or RT. Target tumor response was per RECIST v1.1 criteria. CA19-9 was measured serially. We defined CA19-9 normalization as a value of 37 U/ml after finishing NBTXR3/RT. We compared rates of CA19-9 normalization in this phase 1 trial to a historical cohort of patients who received modern chemo/RT without NBTXR3. As of July 12, 2023, 15 LAPC patients have been treated with NBTXR3/RT. The median age was 63 years [range 43-81], 8 males, 7 females. The first patient (level 1) and subsequent 14 patients (level 2) had no injection complications. Level 2 had 1 non-serious DLT related to RT. At 4 weeks post RT, 13 had stable disease (SD) locally (2 had progressive disease [PD] overall), 1 had PD locally, and 1 had radiographic complete response (CR). At 3 months post RT, 11 had SD locally (1 PD overall), 1 PD locally, and 1 had surgery with negative margins and no residual viable tumor. 9 patients had elevated CA19-9 before NBTXR3/RT, 7 of these 9 (78%) had a decrease in CA19-9 subsequently, and 2 of these 9 (22%) had CA19-9 normalization eventually. 12 patients had elevated CA19-9 at diagnosis, and 5 out of 12 patients (42%) had normalization of CA19-9 after all therapy. We reviewed 455 patients with LAPC/BRPC between 2015-2019 who were treated at our institution as a comparison cohort for CA19-9 normalization rates. Out of 307 patients with elevated CA19-9 at diagnosis and normal bilirubin, 95 normalized (31%) and 212 did not normalize (69%) within 6 months of receiving cytotoxic therapy. The RP2D of NBTXR3 is 42% of GTV. The responses and CA19-9 results in comparison to historical data suggest promising anti-tumor efficacy of NBTXR3/RT. Citation Format: Gabriela Fuentes, Maria J. Rodriguez, Matthew H.G. Katz, Naruhiko Ikoma, Ching-Wei D. Tzeng, Michael Overman, Shubham Pant, Michael S. Lee, Robert A. Wolff, Milind Javle, Cullen M. Taniguchi, Emma B. Holliday, Ethan B. Ludmir, Prajnan Das, Albert C. Koong, Omar I. Vivar, Suyu Liu, Eric P. Tamm, Leonard A. Farber, Manoop S. Bhutani, Eugene J. Koay. Phase I study of endoscopic ultrasound (EUS)-guided NBTXR3 delivery activated by radiotherapy (RT) for locally advanced or borderline resectable pancreatic cancer (LAPC or BRPC) [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr B002.

A sellar-suprasellar malignant optic pathway glioblastoma in the absence of prior radiation therapy: illustrative case.

To date, only a few cases of sellar and suprasellar glioblastomas have been reported even though high-grade glioma constitutes the most common adult brain tumor, commonly arising in the cerebral hemispheres. It arises de novo from astrocytes within the optic nerve, optic chiasm, or optic tracts and is quite challenging to diagnose and treat. To the authors' knowledge, there are 72 cases (including this one) of optic glioma malignancies in the medical literature, 30 corresponding to glioblastomas. The authors present the diagnostic considerations and challenges, management strategies, and clinical course of a very large sellar-suprasellar glioblastoma in a 19-year-female who had never received radiation therapy or prior surgery. Sellar-suprasellar glioblastomas, although extremely rare, are known to occur and pose challenges in their diagnosis and preoperative treatment planning. The presence of diffusion restriction on diffusion-weighted magnetic resonance imaging in a mass lesion that has ring and nodular postcontrast enhancement in addition to absent calcification on computed tomography should be alert to the possibility of a high-grade mass. This is extremely important for preoperative patient counseling and planning for the multimodal treatments, because sellar-suprasellar glioblastomas carry a poorer prognosis than the common benign mass lesions in the region.

Topical Fibronectin - Novel Therapeutic Approach Has Been Formulated for Radiation Induced Skin Reactions

For a long time, radiation-induced skin reactions (RISR) or radiation ulcer (RU) were only encountered in patients undergoing radiation therapy. Nearly 90% of patients having received radiation therapy underwent moderate-to-severe skin reactions such as non-healing wounds, severely reducing patients' quality of life and adversely affecting their disease treatment. Wound healing is significantly delayed in irradiated skin. Fibronectin was the most significantly and consistently downregulated in radiation-damaged skin. From a murine model, we confirmed that radiation leads to decreased fibronectin expression in the skin as well as delayed wound healing. Topically fibronectin was found to significantly improve wound healing in irradiated skin and was associated with decreased inflammatory infiltrate and increased angiogenesis. Fibronectin treatment may be a useful adjunctive modality in the treatment of non-healing radiation wounds. Besides, this review study can be referenced for clinicians to treat RSIs to guide subsequent clinical application.

Modern Radiation Treatment Planning Parameters and Outcomes in Pediatric Tectal Gliomas

Purpose/Objective(s)Pediatric low-grade tectal gliomas are rare, indolent tumors of the brainstem. We reviewed outcomes of pediatric patients diagnosed with low-grade tectal gliomas and report dosimetric parameters for those receiving radiotherapy (RT). Material/MethodsWe retrospectively reviewed all pediatric patients (age <18) at our institution diagnosed with a low-grade glioma between 1993 and 2020 (n=288). Twenty-three patients with tectal gliomas were identified. Patients who received RT (n=8) had detailed dosimetric analyses performed. Doses to critical structures and any resulting toxicities were reviewed. Minimum follow-up was 2 years and complete follow-up was available for all patients. ResultsTwenty-three patients, with a median age of 8.9 years, were included (range 0.5 – 16.2 years). At a median follow-up of 7.4 years (range: 2 – 24 yrs), all were alive at the end of the study period. Three patients (13%) were treated with upfront RT; none of these patients developed local failure (LF) after a median follow-up of 10.6 years. One patient was treated with upfront chemotherapy with no evidence of progression afterwards. Nineteen patients were initially observed after diagnosis and 26% of them (n=5) experienced local progression. All 5 were treated with salvage RT, with one patient requiring further treatment with chemotherapy. Fractionation schedules for patients undergoing upfront or salvage RT included 50.4 Gy in 28 fractions (n = 4), 54 Gy in 30 fractions (n=2), and 51 Gy in 30 fractions (n=2). For patients treated after 2007, the gross tumor volume (GTV) was delineated on a T2 MRI with an average GTV-to-PTV expansion of 4.5 mm (range: 3-5 mm). Detailed dosimetric parameters were available for all patients treated with RT. ConclusionOur review supports the indolent behavior for most tectal gliomas. For the subset of tumors with evidence of progression, modern photon RT results in excellent oncologic outcomes with minimal late effects.

Brain Metastasis in Triple‐Negative Breast Cancer

Background. Breast cancer is an important cause of cancer‐related death in women worldwide and represents the second most frequent cause of brain metastases after lung cancer. The aim of this study was to determine the characteristics and outcomes of triple‐negative breast cancer (TNBC) patients with brain metastasis (BM). Methods. We retrospectively reviewed a cohort of patients diagnosed with TNBC at the “Instituto Nacional de Enfermedades Neoplasicas” (period 2000–2014) to evaluate patients who developed BM. Survival rates were assessed by the Kaplan–Meier method, and prognostic factors were identified with the Cox regression analysis. Results. Of a total of 2007 TNBC patients, 193 (9.62%) developed BM. Of these, 169 stages I–III patients with a median age of 45 years (range:21–78) were included. The stage in this cohort was 4 (2.4%) clinical stage (CS) I, 23 (13.6%) with CS II and 142 (84.0%) with CS III. Most of these patients presented ECOG ≥2 (68.6%). The most common symptom was headache (74.0%), followed by nausea‐vomiting (46.7%). Imaging showed that 80 patients (53.0%) had ≥1 metastatic brain lesion. Regarding the treatment of BM in this cohort, 132 patients (84.6%) received radiotherapy (RT), 2 (1.5%) surgery, and 6 (4.5%) surgery plus RT. The overall survival (OS) rate of BM was 59.8%, 37.3%, and 15.0% at 3, 6, and 12 months, respectively. A multivariate analysis showed RT to be the only factor with a positive impact on the OS of BM (hazard ratio (HR) = 0.48, 95% confidence interval (CI):0.30‐0.77, and p = 0.002), while ECOG ≥2 was associated with a worse OS (HR = 1.69, 95%CI:1.15–2.48, and p = 0.007). Conclusion. Despite the poor prognosis of TNBC patients who develop BM, RT showed a benefit in OS rates, while ECOG ≥2 was the only prognostic factor associated with a worse OS. These results may be useful for multidisciplinary teams for treatment planning in patients with TNBC and BM.

Immune modulation during anti-cancer radio(immuno)therapy.

Cancer can affect all human organs and tissues and ranks as a prominent cause of death as well as an obstruction to increasing life expectancy. A notable breakthrough in oncology has been the inclusion of the immune system in fighting cancer, potentially prolonging life and providing long-term benefits. The concept of "immunotherapy" has been discussed from the 19th and early 20th centuries by Wilhelm Busch, William B. Coley and Paul Ehrlich. This involves distinct approaches, including vaccines, non-specific cytokines and adoptive cell therapies. However, despite the advances made in recent years, questions on how to select the best therapeutic options or how to select the best combinations to improve clinical outcomes are still relevant for scientists and clinicians. More than half of cancer patients receive radiotherapy (RT) as part of their treatment. With the advances in RT and immunotherapy approaches, it is reasonable to consider how to enhance immunotherapy with radiation and vice versa, and to investigate whether combinations of these therapies would be beneficial. In this chapter, we will discuss how the immune system responds to cancer cells and different cancer therapies with a focus on combination of RT and immunotherapy (radioimmunotherapy, RIT).

The Impact of Radiation Therapy on Sexual Health in Breast, Cervix, and Prostate Cancer Patients: A Systematic Review

Purpose: To examine the effects of radiation therapy on sexual health in cervical, breast, and prostate cancer patients. Methods: Four electronic databases (PubMed/PubMed Central, Google Scholar, Embase(Ovid), and SCOPUS) were searched, and articles published in English from January 1, 2011, through 2022 were extracted. Five reviewers independently selected primary studies that reported patient sexual health symptoms caused by cervical, breast, or prostate cancer following radiation therapy treatment. The primary outcome measures sexual health trends during or after radiation therapy through external beam radiotherapy or brachytherapy where applicable. Secondary outcomes measured predictive factors contributing to sexual health scores (age, race, and geographical location). Results: 32 studies with a total of 5033 individuals were included in the systematic review. Overall, 19 studies reported a reduction in sexual health trends, 8 reported mixed trends, and 4 reported no significant trends in sexual health. Of the 10 breast cancer studies, 6 reported decreased sexual well-being, 2 found no trends, and 2 stated mixed trends. Among 12 prostate cancer studies, 5 reported worsening sexual health, 2 found no trends, 1 reported positive sexual functioning, and 4 found mixed trends. Among 10 cervical cancer studies, 8 reported worse sexual health, while 2 reported mixed trends. Younger breast and cervical cancer patients who received radiation therapy experienced greater body image and sexual health concerns. Evidence was insufficient to evaluate trends in geographical location or race between sexual health and radiation therapy. Conclusion: In this study, prostate, breast, and cervical cancer patients who received radiation therapy treatment experienced more troublesome sexual health symptoms compared to non-irradiated cancer patients. Interventions to improve sexual health should be prioritized.

Unmasking anxiety: a head-to-head comparison of open and closed masks in head and neck cancer radiotherapy.

Facemasks accurately immobilise patients with head and neck cancer (HNC) receiving radiotherapy (RT). However, such masks are associated with treatment related distress, a prognostic factor for poorer survival. Open masks offer increased comfort and patient satisfaction. We investigated whether open masks could immobilise patients without affecting treatment accuracy. Over an 18-month period, all HNC RT patients with anxiety were offered open masks. Once 30 patients had completed treatment, set-up data was compared to patients in closed masks. The mean displacement and one-dimensional standard deviations (SD) of the mean, systematic and random set-up errors were calculated for translational directions: anterior-posterior (x), superior-inferior (y), medial-lateral (z). The mean and SD of the mean was calculated for rotational displacements. Mann-Whitney U was used to determine any significant differences between set-up data. Sixty patients were included (30 open & 30 closed masks). There was no statistically significant difference found in the x (p = 0.701), y (p = 0.246) or z (p = 0.535) direction for the SD of the mean displacements between both masks. No statistically significant difference was found in the SD of means for rotational displacements. The calculated planning target volume (PTV) margin requirements were minimally less for the closed masks 3.5, 2.6, and 2.7 mm (x, y, z, respectively) versus 4.2, 3.2, and 3.7 mm, respectively, for open masks. Our study demonstrates that open masks maintain accuracy at levels comparable to closed masks in patients with anxiety. The minor difference in the calculated PTV margin could be rectified with daily on-line imaging or surface guided imaging.

Definitive Local Treatment for Metastatic Prostate Cancer: A National Cancer Database Analysis

Introduction: Prostate cancer (PCa) is the second leading cause of cancer mortality in US males, with metastatic disease (mPCa) comprising 5% of cases. This represents an incurable and uniformly lethal disease. Thus, novel therapeutic approaches are needed. Cytoreductive surgery in the metastatic setting has become commonplace for renal cell carcinoma, and definitive local radiotherapy has been employed in the oligometastatic setting for prostate cancer via the STAMPEDE trial. This study further explores the use of definitive local treatment via pelvic radiotherapy or radical prostatectomy along with androgen deprivation therapy (ADT) vs. ADT alone in the setting of metastatic prostate cancer. Methods: The 2019 National Cancer Database (NCDB) was queried to conduct a retrospective cohort analysis of cT1-4N0-3M1 PCa who received local therapy in conjunction with ADT vs. ADT alone. Clinicopathologic variables were compared between the two groups using Wilcoxon signed rank and Chi-square for continuous and categorical variables, respectively. Overall survival (OS) analysis was performed using Cox Proportional Hazards and the Kaplan-Meier method. Comparisons were made between local therapy + ADT vs. ADT alone and between radical prostatectomy + ADT vs. radiation therapy + ADT vs. ADT alone. Results: A total of n=36,635 patients with cM1 were identified, with 3197 (8.7%) patients receiving local therapy + ADT. Among local therapy + ADT, 2884 (90.2%) patients received radiation therapy + ADT, and 313 (9.8%) received radical prostatectomy + ADT. The median follow-up was 2.8 years. Kaplan-Meier analysis showed significant improvement in 5-year OS for patients who received local therapy + ADT vs. ADT alone. For ADT alone, 5-year OS was 31.3% (CI= 30.7-31.8%) vs. 54.2%. (CI= 52.4-56.1%) for local therapy +ADT. Furthermore, comparing the type of local therapy on Kaplan-Meier analysis: radical prostatectomy + ADT showed better 5-yr OS, 74.0% (CI= 67.5-79.1%) vs. 52.2% (CI= 50.2-54.2%) for radiation therapy +ADT (p&lt;0.001). Conclusion: Definitive local treatment, in addition to ADT, may improve 5-year OS for well-selected patients with metastatic prostate cancer. Patient outcomes are significantly improved for those treated with radical prostatectomy vs. radiation therapy. These findings support multimodal treatment for metastatic prostate cancer, and further studies are needed to optimize criteria for patient selection and choice of definitive localized therapy in this setting.

Development of a question prompt list for Indian cancer patients receiving radiation therapy treatment and their primary family caregivers.

We aimed to develop two question prompt lists (QPLs), one for Indian cancer patients undergoing radiation therapy and the second for their primary family caregivers. The study comprised three phases: (1) qualitative interviews with patients (n=65) and PFCs (n=39) to identify their information needs, queries and concerns regarding RT; (2) development of draft QPLs using conventional content analysis and translation into Hindi and Marathi using European Organisation Research and Treatment of Cancer guidelines; and, (3) A readability analysis, and acceptability study with patients (n=22), PFCs (n=26) and Radiation Oncology (RO) staff (n=20) exploring barriers to QPL implementation. Analysis in Phase I identified questions patients and PFCs asked or wanted to ask their physician. A list of 125 and 136 questions were generated for patients and PFCs, respectively. After five iterations, the draft QPLs were finalised, translated, and back-translated from English into Hindi and Marathi (Phase II). In Phase III, most patients and PFCs reported the QPLs were easy to read, they did not find it difficult to ask the questions, and the questions were not emotionally upsetting. Conversely, RO staff reported concerns that patients may find it difficult to discuss the questions with their physician. The study highlights the need to empower patients and PFCs to ask questions and for staff to feel comfortable answering them. Implementing physician-endorsed QPLs could achieve these aims.

Omission of Radiotherapy in Women >60 Years Old After Breast Conserving Surgery for Breast Cancer is Non-Inferior in Terms of Local Recurrence: A Retrospective Cohort Study.

Local recurrence rate may show no significant differences between women aged 60 and older who receive breast-conserving surgery followed by radiotherapy and those in the same age group who undergo breast-conserving surgery without subsequent radiotherapy. Retrospective cohort study from a single practice with median follow-up time 44 months (interquartile range: 16, 82), comparing women older than 60 years old at diagnosis of breast cancer, treated with breast conserving surgery and either receiving or not receiving radiation therapy postoperatively. The primary endpoint was local recurrence difference between the two groups. Local recurrence did not differ significantly between the two groups in terms of radiotherapy or not [odds ratio (OR) 0.96, 95% confidence interval (CI) 0.89-1.02, Fisher's exact test p = 0.388], nor between two age groups with cut-off at 65 years of age (OR: 0.99, 95% CI 0.92-1.07, Fisher's Exact test p = 0.6). Local recurrence also did not differ when subgroups of age (60-65 years and >66 years) were considered. All patients received 5 years of hormonal therapy. Omission of radiotherapy in selected patients is not inferior to radiotherapy after breast conserving surgery in terms of preventing local recurrence.

Dosimetric comparison of glioblastoma radiotherapy treatment plans on a low-field MRI-guided linear accelerator compared to conventional C-arm linear accelerator

Magnetic resonance imaging (MRI)-guided radiation therapy has proven to provide many benefits such as real-time tracking, dose escalation, and the ability to perform online adaptive therapy. The objective of this study is to compare curative treatment plans for glioblastoma tumors on a low-field MR-guided linac vs a C-arm linac and evaluate if they are comparable in terms of coverage, organ at risk sparing, delivery time, and deliverability. This is a retrospective study that consisted of 15 previously treated patients who received radiation therapy for glioblastoma on a C-arm linac. The CT simulation data used for the original clinical plans was imported into the MR-linac treatment planning system (TPS) and utilized for MR-linac plan generation. The plans were evaluated utilizing the dose volumetric histogram (DVH) and isodose lines, then compared in terms of plan quality consisting of PTV coverage, dose distributions, and OAR constraints. Statistical analysis was performed to compare differences between the two planning techniques. QA was performed on a subset of the plans to verify deliverability. Plans generated on the MR-linac were more heterogenous compared to C-arm linac plans. A statistically significant difference was found in the homogeneity index (HI) and the PTV V105% volume (cc) values. The volume of the normal brain receiving 30 Gy also showed a statistically significant (p = 0.0479) difference, where on average an additional 41.5 cc's of the normal brain tissue received 30 Gy in the MR-linac plans. The maximum dose to the normal brain structure also increased in the MR-linac plans on average by 2.6 Gy (p = 0.0002). Similarly, the average maximum dose to the scalp 4 mm structure was 6.5 Gy higher in the MR-linac plans compared to C-arm linac plans (p = 0.0103). The total MU's were higher in the MR-linac plans compared to the C-arm linac plans (p = 0.0015). Both MR-linac and C-arm linac plans met constraints for PTV coverage and OAR sparing, were deliverable, and resulted to be clinically acceptable. However, our study showed that MR-linac plans were not as conformal or as homogenous as C-arm linac plans utilizing noncoplanar beams.