Factors influencing local control after MR-guided stereotactic body radiotherapy (MRgSBRT) for adrenal metastases.

Purpose: Stereotactic body radiotherapy (SBRT) is an effective treatment for adrenal gland metastases, but it is technically challenging and there are concerns about toxicity. We performed a multi-institutional pooled retrospective analysis to study clinical outcomes and toxicities after MR-guided SBRT (MRgSBRT) using for adrenal gland metastases. Methods and Materials: Clinical and dosimetric data of patients treated with MRgSBRT on a 0.35 T MR-Linac at 11 institutions between 2016 and 2022 were analyzed. Local control (LC), local progression-free survival (LPFS), distant progression-free survival (DPFS) and overall survival (OS) were estimated using Kaplan-Meier method and log-rank test. Results: A total of 255 patients (269 adrenal metastases) were included. Metastatic pattern was solitary in 25.9 % and oligometastatic in 58.0 % of patients. Median total dose was 45 Gy (range, 16-60 Gy) in a median of 5 fractions, and the median BED10 was 100 Gy (range, 37.5-132.0 Gy). Adaptation was done in 87.4 % of delivered fractions based on the individual clinicians' judgement. The 1- and 2- year LPFS rates were 94.0 % (95 % CI: 90.7-97.3 %) and 88.3 % (95 % CI: 82.4-94.2 %), respectively and only 2 patients (0.8 %) experienced grade 3 + toxicity. No local recurrences were observed after treatment to a total dose of BED10 > 100 Gy, with single fraction or fractional dose of > 10 Gy. Conclusions: This is a large retrospective multi-institutional study to evaluate the treatment outcomes and toxicities with MRgSBRT in over 250 patients, demonstrating the need for frequent adaptation in 87.4 % of delivered fractions to achieve a 1- year LPFS rate of 94 % and less than 1 % rate of grade 3 + toxicity. Outcomes analysis in 269 adrenal lesions revealed improved outcomes with delivery of a BED10 > 100 Gy, use of single fraction SBRT and with fraction doses > 10 Gy, providing benchmarks for future clinical trials.

Dosimetric comparison of stereotactic MR-guided radiation therapy (SMART) and HDR brachytherapy boost in cervical cancer.

PURPOSE: The standard of care in locally advanced cervical cancer (LACC) is concomitant chemoradiotherapy followed by high-dose-rate brachytherapy (HDR-BT). Although previous studies compared HDR-BT with stereotactic body radiotherapy (SBRT), there is scarce data regarding the dosimetric outcomes of stereotactic MR-guided adaptive radiation therapy (SMART) boost in lieu of HDR-BT. METHODS AND MATERIALS: In this single-institutional in-silico comparative study, LACC patients who were definitively treated with external beam radiotherapy followed by HDR-BT were selected. Target volumes and organs at risk (OARs) were delineated in MRI and HDR-planning CT. An HDR-BT and a SMART boost plan were generated with a prescribed dose of 28 Gy in four fractions for all patients. The HDR-BT and SMART boost plans were compared in regard to target coverage as well OARs doses. RESULTS: Mean EQD2 D90 to HR-CTV and IR-CTV for HDR-BT plans were 89.7 and 70.5 Gy, respectively. For SMART, the mean EQD2 D90 to HR-PTV, HR-CTV, and IR-CTV were 82.9, 95.4, and 70.2 Gy, respectively. The mean D2cc EQD2 of bladder, rectum, and sigmoid colon for HDR-BT plans were 86.4, 70.7, and 65.7 Gy, respectively. The mean D2cc EQD2 of bladder, rectum, and sigmoid colon for SMART plans were 81.4, 70.8, and 73.6 Gy, respectively. All dose constraints in terms of target coverage and OARs constraints were met for both HDR-BT and SMART plans. CONCLUSIONS: This dosimetric study demonstrates that SMART can be applied in cases where HDR-BT is not available or ineligible with acceptable target coverage and OAR sparing. However, prospective clinical studies are needed to validate these results.

Radiation therapy for prostate cancer in Syrian refugees: facing the need for change.

Purpose: To report the utilization of radiation therapy in Syrian refugee patients with prostate cancer residing in Turkey. Methods and materials: A multi-institutional retrospective review including 14 cancer centers in Turkey was conducted to include 137 Syrian refugee patients with prostate cancer treated with radiation therapy (RT). Toxicity data was scored using the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Noncompliance was defined as a patient missing two or more scheduled RT appointments. Results: Advanced disease, defined as stage III or IV, was reported in 64.2% of patients while androgen deprivation therapy (ADT) was only administrated to 20% of patients. Conventionally fractionated RT with a median number of 44 fractions was delivered to all patients with curative intent (n = 61) while palliative RT (n = 76) was delivered with a median number of 10 fractions. The acute grade 3-4 toxicity rate for the entire cohort was 16%. Noncompliance rate was 42%. Conclusion: Most Syrian refugee prostate cancer patients presented with advanced disease however ADT was seldom used. Despite the low treatment compliance rate, conventional fractionation was used in all patients. Interventions are critically needed to improve screening and increase the use of standard-of-care treatment paradigms, including hypofractionated RT and ADT.

A new perspective on the future of Turkish Society for Radiation Oncology: Young Radiation Oncologists Group (TROD/GROG 001).

Radiation oncology is a field of medicine that has been rapidly growing with advances in technology, radiobiology, treatment algorithms and quality of life of modern radiotherapy over the last century. In the context of these advances, it is critical to be aware of the role of the young radiation oncologists and enable them to discover new perspectives. For this purpose, "The Young Radiation Oncologists Group" (GROG) has been established by the Turkish Society for Radiation Oncology (TROD), a subgroup which has focused on the professional developments, early career and integrating into the TROD family while supporting education and innovative research of young radiation oncologists. The purpose of this paper was to outline the structure and responsibilities of GROG and its scientific and social activities within TROD and in its own right.

Magnetic Resonance Imaging-Guided Radiation Therapy for Early-Stage Gastric Mucosa-Associated Lymphoid Tissue Lymphoma.

Lymphoid neoplasia derived from mucosa-associated lymphoid tissue (MALT; also abbreviated as MALToma) is most commonly seen in the stomach. Radiotherapy (RT) is indicated in early-stage disease as a standard of care. With the advent of RT techniques, large field irradiation was replaced by involved site and involved field approaches. Magnetic resonance imaging-guided online adaptive RT (MRgRT) has the advantage of better soft tissue visualization, adaptive planning before each fraction, and online tumor tracking during treatment; hence, it could be a safe and effective choice for gastric MALToma patients. Herein, we investigated the interfractional changes in target and the impact of MRgRT on daily dosimetry in a gastric MALToma case. A patient diagnosed with MALToma who failed to respond to antibacterial treatment was referred to our clinic for RT. He was found to be suitable for MRgRT. We treated the patient with MRgRT in 20 fractions to a total dose of 30 Gy. Reoptimized adaptive plans were generated before each fraction since the coverages of the original plan were inadequate in each fraction. The patient showed good compliance and tolerated the treatment well. To our knowledge, this is the first documented case of a gastric MALToma treated with MRgRT. MRgRT is safe and feasible for this patient group with improved target coverage using small planning target volume margins. Without online adaptive planning, the target coverages would be inadequate and we would risk surrounding tissues to get higher doses.

Stereotactic Radiotherapy for Adrenal Metastases: A Multi-Institutional Review of Patient Characteristics and Outcomes - Turkish Society for Radiation Oncology SBRT Group Study (Trod SBRT 10-004).

INTRODUCTION: This study aimed to report the outcomes of stereotactic body radiotherapy (SBRT) for adrenal metastasis in a retrospective multi-institutional cohort. METHODS: The outcomes of 124 patients with 146 adrenal metastases who underwent SBRT within 11 years (2008-2019) were retrospectively evaluated. Survival outcomes were analyzed by the Kaplan-Meier method. Patient, tumor, and treatment characteristics and their effects on survival, local control (LC), and toxicity outcomes were analyzed by log-rank and multivariate Cox regression methods. RESULTS: The median age was 60 years. The most frequent primary tumor site was the lung, followed by the gastrointestinal system and breast. The adrenal gland was the only metastatic site in 49 (40%) patients. Median biologically effective dose (BED)10 was 61 Gy. The overall LC rate was 83%, and it was positively correlated with the BED10 and fraction dose. The 1- and 2-year local recurrence-free survival, overall survival (OS), and progression-free survival (PFS) rate was 79% and 69%, 83% and 60%, and 31% and 12%, respectively. OS significantly improved with non-lung cancer and <4-cm lesion and PFS with a fraction dose ≥8 Gy, BED10 >65 Gy, and an isolated adrenal metastasis. Fourteen patients reported an acute toxicity, and late toxicity was observed in 3 patients, including one grade 5. CONCLUSION: A satisfactory LC rate was achieved for adrenal metastasis via SBRT. A higher BED10 and fraction dose were positive prognostic factors for tumor control. However, the main problem is DM in these patients, and systemic treatment options are needed to be improved.

Access to Radiation Therapy by Syrian Refugees Displaced to Turkey.

For over 10 years, the Syrian conflict has caused millions of people to leave their homeland, causing one of the biggest refugee crises in modern history. Considering its prevalence, cancer is an important care burden among Syrian refugees. Radiation therapy is one of the essential parts of cancer treatment, and radiation oncology departments must guarantee optimal cancer treatments even in such a challenging setting when patients are displaced forcefully from their homes. National and institutional measures are highlighted in this manuscript to provide suggestions for the delivery of care during refugee crises. There are two issues creating barriers to serving refugee populations: the loss of access to their original care records in Syria for those with a previous diagnosis of cancer referred for continuation of radiation therapy or reirradiation, and the effect of acute radiation therapy toxicity on treatment compliance.

Multi-Institutional Outcomes of Stereotactic Magnetic Resonance Image Guided Adaptive Radiation Therapy With a Median Biologically Effective Dose of 100 Gy10 for Non-bone Oligometastases.

Purpose: Randomized data show a survival benefit of stereotactic ablative body radiation therapy in selected patients with oligometastases (OM). Stereotactic magnetic resonance guided adaptive radiation therapy (SMART) may facilitate the delivery of ablative dose for OM lesions, especially those adjacent to historically dose-limiting organs at risk, where conventional approaches preclude ablative dosing. Methods and Materials: The RSSearch Registry was queried for OM patients (1-5 metastatic lesions) treated with SMART. Freedom from local progression (FFLP), freedom from distant progression (FFDP), progression-free survival (PFS), and overall survival (LS) were estimated using the Kaplan-Meier method. FFLP was evaluated using RECIST 1.1 criteria. Toxicity was evaluated using Common Terminology Criteria for Adverse Events version 4 criteria. Results: Ninety-six patients with 108 OM lesions were treated on a 0.35 T MR Linac at 2 institutions between 2018 and 2020. SMART was delivered to mostly abdominal or pelvic lymph nodes (48.1%), lung (18.5%), liver and intrahepatic bile ducts (16.7%), and adrenal gland (11.1%). The median prescribed radiation therapy dose was 48.5 Gy (range, 30-60 Gy) in 5 fractions (range, 3-15). The median biologically effective dose corrected using an alpha/beta value of 10 was 100 Gy10 (range, 48-180). No acute or late grade 3+ toxicities were observed with median 10 months (range, 3-25) follow-up. Estimated 1-year FFLP, FFDP, PFS, and OS were 92.3%, 41.1%, 39.3%, and 89.6%, respectively. Median FFDP and PFS were 8.9 months (95% confidence interval, 5.2-12.6 months) and 7.6 months (95% confidence interval, 4.5-10.6 months), respectively. Conclusions: To our knowledge, this represents the largest analysis of SMART using ablative dosing for non-bone OM. A median prescribed biologically effective dose of 100 Gy10 resulted in excellent early FFLP and no significant toxicity, likely facilitated by continuous intrafraction MR visualization, breath hold delivery, and online adaptive replanning. Additional prospective evaluation of dose-escalated SMART for OM is warranted.

Utilization of radiation therapy and predictors of noncompliance among Syrian refugees in Turkey.

BACKGROUND: Access to cancer care is a problem that continues to plague refugees displaced from their home countries. The turbulent political crisis in Syria, which has led to millions of refugees seeking asylum in Turkey, merits further attention. We aimed to study the rate of utilization of radiation therapy among Syrian refugees with cancer living in Turkey in an attempt to identify the contributing factors predictive of non-compliance with prescribed RT. METHODS: In this retrospective review of 14 institutional databases, Syrian refugee patients in Turkey with a cancer diagnosis from January 2015 to December 2019 who were treated with RT were identified. The demographic data, treatment compliance rates, and toxicity outcomes in these patients were surveyed. Variable predictors of noncompliance such as age, sex, diagnosis, treatment length, and toxicity were studied. The association between these variables and patient noncompliance was determined. RESULTS: We identified 10,537 patients who were diagnosed with cancer during the study period, of whom 1010 (9.6%) patients were treated with RT. Breast cancer (30%) and lung cancer (14%) were the most common diagnoses with up to 68% of patients diagnosed at an advanced stage (Stage III, IV). 20% of the patients were deemed noncompliant. Treatment with concurrent chemoradiotherapy (OR 1.61, 95% CI 1.06-2.46, p = 0.023) and living in a refugee camp (OR 3.62, 95% CI 2.43-5.19, p < 0.001) were associated with noncompliance. Age, sex and treatment length were not significantly associated with noncompliance. CONCLUSIONS: Noncompliance with radiotherapy among Syrian refugees in Turkey remains an area of concern with a multitude of factors contributing to these alarming numbers. Further studies to better ascertain the finer nuances of this intricately complex problem and a global combination of efforts can pave the way to providing a solution.

Outcomes of carotid sparing intensity-modulated radiotherapy for early stage glottic cancer in 201 patients: Multicenter study of Turkish Radiation Oncology Society/TROD-01-007.

BACKGROUND: To assess and report clinical outcomes after carotid sparing intensity-modulated radiotherapy for early stage laryngeal cancer. METHODS: We retrospectively analyzed 201 patients with early stage glottic laryngeal cancer treated with carotid sparing intensity-modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) techniques in six TROD centers. RESULTS: After a median follow-up of 31 months the actuarial 1- and 3-year local and locoregional control rates were 99.4% and 94.7%, 98.4% and 93%, respectively. T classification, anterior commissure involvement, IMRT technique, and type of fractionation were not found to be prognostic for local control. Overall, eight patients had lost their organ function due to recurrence or toxicity. Grade 3 and 4 acute laryngeal edema was seen in eight (4%) and one (0.5%) of patients, respectively. Grade 3 and 4 late laryngeal edema developed in two (1%) and one patient (0.5%), respectively. CONCLUSION: Oncologic outcomes of patients treated with carotid sparing IMRT were excellent; comparable with historical series, with acceptable side effects. Longer follow-up is needed to estimate long term effect on stroke.

Magnetic Resonance Image-Guided Hypofractionated Ablative Radiation Therapy for Hepatocellular Carcinoma With Tumor Thrombus Extending to the Right Atrium.

Hepatocellular carcinoma (HCC) presenting with tumor thrombus (TT) and inferior vena cava (IVC)/right atrium (RA) infringement point to an advanced-stage disease that is deemed inoperable. Stereotactic body radiotherapy is an emerging treatment option for this group of patients with promising outcomes in recent studies that are comparable to conventional treatment methods, namely, transarterial chemoembolization and transarterial radioembolization. Here, we report a case of HCC with RA extension through the IVC. The patient was referred to our clinic for treatment options, and he was found suitable for magnetic resonance imaging-guided radiotherapy (MRgRT). We treated the patient with MRgRT in five fractions to a total dose of 40 Gray. The tumor was tracked during the treatment sessions, and adaptive treatment planning was performed before each fraction. The patient tolerated the treatment well with no acute grade 3-4 toxicities. The last follow-up showed that the patient had a complete biochemical response and is now a candidate for an orthotopic liver transplant. To our knowledge, this report is the first to document the MRgRT treatment of an HCC with TT and RA extension. MRgRT is safe and feasible for this patient group and can be an effective bridging therapy for liver transplants.

Magnetic Resonance Imaging-Guided Online Adaptive Lattice Stereotactic Body Radiotherapy in Voluminous Liver Metastasis: Two Case Reports.

Lattice Radiotherapy (LRT) is a technique in which heterogeneous doses are delivered to the target so large tumors can have optimal doses of radiation without compromising healthy tissue sparing. To date, case reports and case series documented its application for bulky tumors mainly in the pelvic region. LRT not only provides dosimetric advantages but also promotes tumor control by triggering some radiobiological and immunological pathways. We report two cases of giant liver metastases for whom other treatment options were not suitable. We treated both patients with Magnetic Resonance Image-Guided Radiotherapy (MRgRT) with online adaptive LRT (OALRT) technique. Adaptive plans were generated before each fraction. Tumors were observed to have regressed interfractionally so the location and number of spheres were adapted to tumor size and daily anatomy of the surrounding organs at risk (OAR). Both patients had good treatment compliance without any Grade 3+ side effects. They are both under follow-up and report improvement. By reporting the first application of OALRT by using MRgRT in liver metastases, we show that MRgRT is a promising modality for LRT technique with better target and OAR visualization as well as online adaptive planning before each fraction according to the daily anatomy of the patient.

Watch and Wait Strategy for Rectal Cancer: How Long Should We Wait for a Clinical Complete Response?

BACKGROUND: The objective of this study was to determine how long to wait in locally advanced rectal tumor (LARC) patients who receive total neoadjuvant therapy (TNT) and achieve a clinical complete response (cCR), and to identify the clinical parameters that affect the waiting period for the watch-and-wait strategy (W &W). MATERIALS AND METHODS: The data of patients who achieved cCR between February 2015 and June 2020 were examined retrospectively. The week in which patients with cCR at the end of TNT achieved clearance was determined by reanalyzing recorded endoscopy video images. In the assessment at the time of the initial diagnosis, tumor characteristics, such as digital rectal examination findings, MRI stage, location with respect to the puborectalis muscle, annularity, and tumor size, were recorded prospectively. RESULTS: A total of 54 patients were included in this study. According to the MRI-T stage, 14 cases were cT3a, 22 were cT3b, and 18 were cT3c-T4. Forty-four percent of the cases achieved cCR at 8-10 weeks, 19% at 12-16 weeks, 20% at 16-22 weeks, and 17% at 20-26 weeks. Patients with tumors that were early MRI-T stage (cT3a), negative clinical circumferential resection margin, mobile, small (≤4 cm), located above the puborectalis muscle and showed <180 degrees annularity achieved cCR significantly earlier than those with other tumors (p<0.05). CONCLUSION: In this study, cCR was achieved in less than half (44%) of the cases during the 8-10 week waiting period. In the W&W strategy, the initial assessment for cCR seems insufficient, and we may need to wait up to 26-30 weeks, especially in patients with advanced-stage tumors.

Risk of symptomatic radiation necrosis in patients treated with stereotactic radiosurgery for brain metastases.

INTRODUCTIO: Stereotactic radiosurgery (SRS) is a treatment option in the initial management of patients with brain metastases. While its efficacy has been demonstrated in several prior studies, treatment-related complications, particularly symptomatic radiation necrosis (RN), remains as an obstacle for wider implementation of this treatment modality. We thus examined risk factors associated with the development of symptomatic RN in patients treated with SRS for brain metastases. PATIENTS AND METHODS: We performed a retrospective review of our institutional database to identify patients with brain metastases treated with SRS. Diagnosis of symptomatic RN was determined by appearance on serial MRIs, MR spectroscopy, requirement of therapy, and the development of new neurological complaints without evidence of disease progression. RESULTS: We identified 323 brain metastases treated with SRS in 170 patients from 2009 to 2018. Thirteen patients (4%) experienced symptomatic RN after treatment of 23 (7%) lesions. After SRS, the median time to symptomatic RN was 8.3 months. Patients with symptomatic RN had a larger mean target volume (p<0.0001), and thus larger V100% (p<0.0001), V50% (p<0.0001), V12Gy (p<0.0001), and V10Gy (p=0.0002), compared to the rest of the cohort. Single-fraction treatment (p=0.0025) and diabetes (p=0.019) were also significantly associated with symptomatic RN. CONCLUSION: SRS is an effective treatment option for patients with brain metastases; however, a subset of patients may develop symptomatic RN. We found that patients with larger tumor size, larger plan V100%, V50%, V12Gy, or V10Gy, who received single-fraction SRS, or who had diabetes were all at higher risk of symptomatic RN.

Magnetic resonance image-guided hypofractionated ablative radiation therapy for extrahepatic cholangiocarcinoma: Plan adaptation in changing anatomy.

Extrahepatic cholangiocarcinoma is an aggressive malignancy of biliary duct epithelium which typically has a poor prognosis. Although surgical resection improves overall survival, many patients are deemed medically inoperable or have unresectable tumors. Herein, we report a case of an 84-year-old Caucasian male who was diagnosed with medically inoperable extrahepatic cholangiocarcinoma. Magnetic resonance image-guided hypofractionated ablative radiotherapy was administered which has the advantages of superior soft tissue resolution, better visualization of the target and organ at risk, daily online adaptive planning and continuous cine MR tracking of the target during irradiation. Concomitant chemotherapy was used. On the first fraction the patient presented with a broken arm that forced the patient take a treatment position much different than the one used for simulation CT and planning. The patient was able to finish the treatment without the need of another simulation by adapting the plan according to the new anatomy. The patient is being followed up until today and is alive with no evidence of disease.

Stereotactic MR-guided online adaptive radiation therapy (SMART) for the treatment of liver metastases in oligometastatic patients: initial clinical experience.

PURPOSE: We aimed to present our initial clinical experience on the implementation of a stereotactic MR-guided online adaptive radiation therapy (SMART) for the treatment of liver metastases in oligometastatic disease. MATERIALS AND METHODS: Twenty-one patients (24 lesions) with liver metastasis treated with SMART were included in this retrospective study. Step-and-shoot intensity-modulated radiotherapy technique was used with daily plan adaptation. During delivery, real-time imaging was used by acquiring planar magnetic resonance images in sagittal plane for monitoring and gating. Acute and late toxicities were recorded both during treatment and follow-up visits. RESULTS: The median follow-up time was 11.6 months (range, 2.2 to 24.6 months). The median delivered total dose was 50 Gy (range, 40 to 60 Gy); with a median fraction number of 5 (range, 3 to 8 fractions) and the median fraction dose was 10 Gy (range, 7.5 to 18 Gy). Ninety-three fractions (83.7%) among 111 fractions were re-optimized. No patients were lost to follow-up and all patients were alive except one at the time of analysis. All of the patients had either complete (80.9%) or partial (19.1%) response at irradiated sites. Estimated 1-year overall survival was 93.3%. Intrahepatic and extrahepatic progression-free survival was 89.7% and 73.5% at 1 year, respectively. There was no grade 3 or higher acute or late toxicities experienced during the treatment and follow-up course. CONCLUSION: SMART represents a new, noninvasive and effective alternative to current ablative radiotherapy methods for treatment of liver metastases in oligometastatic disease with the advantages of better visualization of soft tissue, real-time tumor tracking and potentially reduced toxicity to organs at risk.

Oligometastatic Bone Disease in Castration-Sensitive Prostate Cancer Patients Treated With Stereotactic Body Radiotherapy Using 68Ga-PSMA PET/CT: TROD 09-004 Study.

PURPOSE: To evaluate the outcomes of metastasis-directed treatment (MDT) using stereotactic body radiotherapy (SBRT) for bone-only oligometastasis (OM) detected with gallium prostate-specific membrane antigen (68Ga-PSMA) PET/CT in castration-sensitive prostate cancer (PC) patients. METHODS: In this multi-institutional study, clinical data of 74 PC patients with 153 bone lesions who were undergoing MDT were retrospectively evaluated. Twenty-seven patients (36.5%) had synchronous, and 47 (63.5%) had metachronous OM. All patients had PC with 5 metastases or fewer detected by 68Ga-PSMA PET/CT and treated using SBRT with a median dose of 20 Gy. The prognostic factors for PC-specific survival (PCSS) and progression-free survival (PFS) were analyzed. RESULTS: The median follow-up was 27.3 months. Patients with synchronous OM were older and received higher rates of androgen deprivation therapy after SBRT compared with patients with metachronous OM. The 2-year PCSS and PFS rates were 92.0% and 72.0%, respectively. A prostate-specific antigen (PSA) decline was observed in 56 patients (75.7%), and 48 (64.9%) had a PSA response defined as at least 25% decrease of PSA after MDT. The 2-year local control rate per lesion was 95.4%. In multivariate analysis, single OM and PSA response after MDT were significant predictors for better PCSS and PFS. In-field recurrence was observed in 4 patients (6.5%) with 10 lesions at a median of 13.1 months after MDT completion. No serious late toxicity was observed. CONCLUSIONS: We demonstrated that SBRT is an efficient and well-tolerated treatment option for PC patients with 5 bone-only oligometastases or fewer detected with 68Ga-PSMA PET/CT.

Magnetic resonance image-guided stereotactic body radiation therapy for liver rhabdoid tumor in infancy: A case report.

Extracranial malignant rhabdoid tumors are rare and aggressive tumors that typically occur in the pediatric age group and have a poor prognosis. Herein, we report a case of a one year and five months old male infant who was referred with the diagnosis of malignant rhabdoid tumor of the liver. Magnetic resonance guided stereotactic body radiotherapy was administered with concomitant chemotherapy. Treatment was well tolerated with no severe acute side effects. A 40.8% volumetric reduction of the tumor was observed at the last fraction of MR guided radiotherapy.

Multi-institutional validation of the ESMO-ESGO-ESTRO consensus conference risk grouping in Turkish endometrial cancer patients treated with comprehensive surgical staging.

In this study, 683 patients with endometrial cancer (EC) after comprehensive surgical staging were classified into four risk groups as low (LR), intermediate (IR), high-intermediate (HIR) and high-risk (HR), according to the recent consensus risk grouping. Patients with disease confined to the uterus, ≥50% myometrial invasion (MI) and/or grade 3 histology were treated with vaginal brachytherapy (VBT). Patients with stage II disease, positive/close surgical margins or extra-uterine extension were treated with external beam radiotherapy (EBRT)±VBT. The median follow-up was 56 months. The overall survival (OS) was significantly different between LR and HR groups, and there was a trend between LR and HIR groups. Relapse-free survival (RFS) was significantly different between LR and HIR, LR and HR and IR and HR groups. There was no significant difference in OS and RFS rates between the HIR and HR groups. In HR patients, the OS and RFS rates were significantly higher in stage IB - grade 3 and stage II compared to stage III and non-endometrioid histology without any difference between the two uterine-confined stages and between stage III and non-endometrioid histology. The current risk grouping does not clearly discriminate the HIR and IR groups. In patients with comprehensive surgical staging, a further risk grouping is needed to distinguish the real HR group.Impact statementWhat is already known on this subject? The standard treatment for endometrial cancer (EC) is surgery and adjuvant radiotherapy (RT) and/or chemotherapy is recommended according to risk factors. The recent European Society for Medical Oncology (ESMO), European Society of Gynaecological Oncology (ESGO) and European Society for Radiotherapy and Oncology (ESTRO) guideline have introduced a new risk group. However, the risk grouping is still quite heterogeneous.What do the results of this study add? This study demonstrated that the current risk grouping recommended by ESMO-ESGO-ESTRO does not clearly discriminate the intermediate risk (IR) and high-intermediate risk (HIR) groups.What are the implications of these findings for clinical practice and/or further research? Based on the results of this study, a new risk grouping can be made to discriminate HIR and IR groups clearly in patients with comprehensive surgical staging.

Magnetic resonance image-guided adaptive stereotactic body radiotherapy for prostate cancer: preliminary results of outcome and toxicity.

OBJECTIVE: Using moderate or ultra-hypofractionation, which is also known as stereotactic body radiotherapy (SBRT) for treatment of localized prostate cancer patients has been increased. We present our preliminary results on the clinical utilization of MRI-guided adaptive radiotherapy (MRgRT) for prostate cancer patients with the workflow, dosimetric parameters, toxicities and prostate-specific antigen (PSA) response. METHODS: 50 prostate cancer patients treated with ultra-hypofractionation were included in the study. Treatment was performed with intensity-modulated radiation therapy (step and shoot) technique and daily plan adaptation using MRgRT. The SBRT consisted of 36.25 Gy in 5 fractions with a 7.25 Gy fraction size. The time for workflow steps was documented. Patients were followed for the acute and late toxicities and PSA response. RESULTS: The median follow-up for our cohort was 10 months (range between 3 and 29 months). The median age was 73.5 years (range between 50 and 84 years). MRgRT was well tolerated by all patients. Acute genitourinary (GU) toxicity rate of Grade 1 and Grade 2 was 28 and 36%, respectively. Only 6% of patients had acute Grade 1 gastrointestinal (GI) toxicity and there was no Grade ≥ 2 GI toxicity. To date, late Grade 1 GU toxicity was experienced by 24% of patients, 2% of patients experienced Grade 2 GU toxicity and 6% of patients reported Grade 2 GI toxicity. Due to the short follow-up, PSA nadir has not been reached yet in our cohort. CONCLUSION: In conclusion, MRgRT represents a new method for delivering SBRT with markerless soft tissue visualization, online adaptive planning and real-time tracking. Our study suggests that ultra-hypofractionation has an acceptable acute and very low late toxicity profile. ADVANCES IN KNOWLEDGE: MRgRT represents a new markerless method for delivering SBRT for localized prostate cancer providing online adaptive planning and real-time tracking and acute and late toxicity profile is acceptable.