Local Control Rates Research Articles

Long-Term Outcomes of Thymoma Treated at a Single Institute

Introduction Thymomas are uncommon tumors that originate from epithelial cells of thymus and may have varying clinical course. Materials and Methods A retrospective review of medical records of thymoma patients treated between January 2012 and April 2022 at our institute was conducted. Results There were a total of 23 patients (12 males and 11 females) with median age of 52 years (range, 33–77 years). Eleven patients (47.8%) had associated paraneoplastic syndromes of which 10 (43.5%) had myasthenia gravis and 1 (4.3%) had pure red cell aplasia. Average maximal tumor diameter was 62 mm (28–160 mm). Masaoka-Koga stage distribution was as follows: stage I (n = 2, 8.7%), IIA (n = 4, 17.4%), IIB (n = 1, 4.3%), IIIA (n = 2, 8.7%), IIIB (n = 4, 17.4%), IVA (n = 7, 30.4%), and IVB (n = 3, 13.1%). The World Health Organization type B2 was the commonest histology (n = 12, 52.17%), followed by B3 (n =7, 30.4%), B1 (n = 2, 8.7%), AB (n = 1,4.3%), and A (n = 1, 4.3%). Six patients received neoadjuvant chemotherapy with cyclophosphamide regimen, 22 (95.6%) underwent surgery, and 1 patient received adjuvant chemotherapy. R0 resection was attained in 20 (91%) patients, R1 resection in 1 (4.5%) patient, and R2 in 1 (4.5%) patient. All operated patients underwent postoperative radiotherapy (45–60 Gy in 25–30 fractions). Four patients relapsed at a median duration of 14 months (2–26 months). At a median follow-up of 6 years, 5-year overall survival was 67.1% and 5-year progression-free survival was 66.6%. Local control at 5 years was 86.6%. Conclusion Despite majority of our patients presenting at an advanced stage, the local control rates are encouraging and reinforce multimodality approach.

Local tumour control and patient survival after ruthenium-106 brachytherapy for small choroidal melanoma

AimTo report local tumour control, metastasis and survival rates of patients with small choroidal melanoma (CM) after treatment with ruthenium-106 (Ru-106) plaque brachytherapy.MethodsRetrospective case series of 353 consecutive eyes with...

71 Stereotactic Ablative Radiotherapy Is a Safe and Feasible Treatment Option for Patients with Hepatocellular Carcinoma

Abstract Aim Stereotactic ablative body radiotherapy (SABR) is a highly focused radiation treatment that delivers an intense dose of radiation to a tumour whilst limiting exposure of surrounding tissues. SABR has been associated with improvement in survival and good rates of local control in non-surgical candidates with hepatocellular carcinoma (HCC). The aim of this study was to evaluate the outcomes of HCC patients treated with SABR after its introduction in a tertiary referral hepatobiliary centre. Method A total of 32 patients (median age 73 years {47 to 85}, 78% male) who received SABR for HCC liver lesions between July 2020 and August 2022 were retrospectively analysed. Patient, treatment, and follow-up details were obtained from online patient records and imaging. Results Overall Survival rate was 78% at a median follow-up of 12 months (range 4 to 30). Local control was achieved in 72%, while progression occurred in 31%. Median time to progression was 6 months (range 3 to 31). The rate of progression-free survival at 12 months was 62.5%. Only 31% reported toxicities. No patients in the study group experienced any Grade ³ 3 toxicities. Conclusions Our experience following the introduction of SABR for patients with HCC is that SABR is a viable, well-tolerated and effective treatment option in this patient group. Further research is warranted to examine the clinical benefits of combination treatment with SABR and other treatment modalities to maximise disease control in patients with both early and advanced HCC.

Radiotherapy for Solitary Bony or Extramedullary Plasmacytoma.

This study aimed to determine the oncological outcomes associated with curative radiotherapy for solitary bony or extramedullary plasmacytomas by drawing on clinical data from a single tertiary center. This study aimed to provide a comprehensive understanding of the efficacy of radiotherapeutic interventions and delineate the patterns of disease recurrence. Eleven consecutive patients diagnosed with solitary bony or extramedullary plasmacytomas and treated between May 2007 and November 2023 were retrospectively screened. Different radiotherapy doses and fractionations were employed, and statistical analyses were performed to assess overall survival (OS) and disease-free survival (DFS). Among the 11 patients (9 males and 2 females), primary tumors were located within the bone in seven patients, whereas extramedullary tumors were observed in four patients. The median prescribed radiation dose was 46 Gy. The 5-year OS and DFS were 83.3% and 28.9%, respectively. Progression to multiple myeloma occurred in four patients with primary bony plasmacytoma. Local control rate was 88.9%, and one patient experienced distant metastasis after 32 months. Bony plasmacytoma has a high tendency of leading to multiple myeloma rather than extramedullary plasmacytoma (5-year progression to multiple myeloma-free survival rate, 20.8% vs. 100%, p=0.08). Radiotherapy is effective for solitary plasmacytomas with favorable local control and high objective response rates. A comparison with the existing literature supports the role of radiotherapy in the management of these conditions. The differences in outcomes between bony and extramedullary plasmacytomas emphasize the need for personalized treatment approaches.

Effects of Chemotherapy and Radiation Therapy on Early Laryngeal Cancers.

Treatments for early laryngeal squamous cell carcinoma (SCC) include radiotherapy (RT), chemoradiotherapy (CRT), and larynx-preserving surgery. In this study, early laryngeal SCC was treated with RT in patients with stage I (T1N0) tumors and with CRT and docetaxel (DOC) in patients with stage II (T2N0) tumors and the treatment results and effectiveness of the chemotherapy were compared. A total of 78 patients with early-stage laryngeal SCC were enrolled in this study. The T1N0 patients received radiation for the primary lesions as outpatients at a total dose of 63-70 Gy. By contrast, the T2N0 patients were hospitalized and treated with CRT, receiving a total radiation dose of 66-70 Gy. Docetaxel (DOC, 10 mg/m2) was administered intravenously once a week for 6-8 consecutive weeks concurrently with radiotherapy. The adverse events and survival rates with local control rates were examined. The number of non-glottic T2N0 patients was significantly higher than that of T1N0 patients. Although all patients completed their treatment schedule, significantly more grade 3 adverse events were observed in the T2N0 patients, in particular mucositis and dermatitis, than in T1N0 patients. The 5-year overall survival rate, disease specific survival rate, local control rate, and laryngeal preserve rate of the T1N0 and T2N0 patients were 86.1, 93.3, 88.6, and 94.3% and 85.9, 88.0, 93.1, and 93.1%, respectively. CRT with docetaxel showed the best therapeutic outcomes for the treatment of laryngeal SCC in patients with T2N0 tumours, with a higher local control rate, effective laryngeal preservation, and relatively few adverse events.

Stereotactic Body Radiation Therapy for Primary Renal Cell Carcinoma: A Case-Based Radiosurgery Society Practice Guide

Traditionally, renal cell carcinoma (RCC) was considered a radioresistant tumor, thereby limiting definitive radiation therapy management options. However, several recent studies have demonstrated that stereotactic body radiation therapy (SBRT) can achieve high rates of local control for the treatment of primary RCC. In the setting of expanding use of SBRT for primary RCC, it is crucial to provide guidance on practical considerations such as patient selection, fractionation, target delineation, and response assessment. This is particularly important in challenging scenarios where a paucity of evidence exists, such as in patients with a solitary kidney, bulky tumors, or tumor thrombus. The Radiosurgery Society endorses this case-based guide to provide a practical framework for delivering SBRT to primary RCC, exemplified by 3 cases. This article explores topics of tumor size and dose fractionation, impact on renal function and treatment in the setting of a solitary kidney, and radiation's role in the management of inferior vena cava tumor thrombus. Additionally, we review existing evidence and expert opinion on target delineation, advanced techniques such as magnetic resonance imaging guided SBRT, and SBRT response assessment.

Pattern of care and clinical outcome of patients with carcinoma endometrium and the impact of central histopathological review on management: A tertiary cancer centre experience.

Endometrial carcinoma (EC) is the third most common gynecological malignancy in India. Recent PORTEC-3 analysis emphasized the role of central histopathological review. We aimed to retrospectively analyze the demographic and histopathological characteristics of EC patients treated at our institute and assess the impact of the central histopathological review on management and also analyze clinical outcomes in this cohort of patients. Data of 75 EC patients treated at our center between 2013 and 2022 were retrieved from our departmental archives. Patients were analyzed for demographic details, histopathological findings, details of surgery and histopathology (HPE), results of a review of HPE, adjuvant treatment details, and clinical outcomes. All patients with HPE outside of our institute were reviewed at our center prior to initiation of treatment. In cases of discordance, patients were discussed in the multidisciplinary tumor board for the final treatment decisions. Patients were staged as per International Federation of Gynaecology and Obstetrics 2018. The median age was 57 years (range: 37-74 years). Twenty-seven patients with HPE reported from the outside center were reviewed at our institute and changes were observed in 26 patients (96.3%). HPE review changes were observed in terms of histological grade, histological type, myometrial invasion, and lymph node involvement in five (18.5%), three (11.1%), seven (25.9%), and three (42.8%), respectively. HPE review leads to changes in the management of 19/26 patients. Stage distribution was I: II: III in 48 (64%): 9 (13.3%): 18 (24%) patients, respectively. The median external beam radiotherapy dose was 50 Gray (range: 45-50.4 Gray at 1.8-2 Gray per fraction). The median brachytherapy dose for patients treated with brachytherapy alone was 7 Gray each for three sessions and in combination with EBRT was 6 Gray each in two sessions. At a median follow-up of 51 months (range: 6-116 months), seven (9.3%) patients developed distant metastasis, two (2.7%) patients had local plus distant metastasis, and two (2.7%) patients had local recurrence. The overall survival and disease-free survival rates at 3 years were 93.5% and 86.7%, respectively. EC patients treated at our center have excellent local control rates with a combination of external beam radiotherapy and brachytherapy. The central histopathological review may result in changes impacting patient management and should be routinely done prior to initiation of treatment in EC.

Phase II Trial Assessing Toxicity of Personalized Response-Based Radiation Treatment in Patients with Locally Advanced Non-Small Cell Lung Cancer

IntroductionLocal failure rates after treatment for locally advanced non-small-cell lung cancer (NSCLC) remain high. Efforts to improve local control with uniform dose-escalation or dose-escalation to mid-treatment PET-avid residual disease have been limited by heightened toxicity. This trial aimed to refine response-based adaptive radiation (RT) and minimize toxicity by incorporating FDG-PET and V/Q SPECT imaging mid-treatment. Methods47 patients with Stage IIA-III unresectable NSCLC were prospectively enrolled in this single-institution trial (NCT02492867). Patients received concurrent chemoradiation with personalized response-based adaptive RT over 30 fractions incorporating V/Q SPECT and FDG-PET. The first 21 fractions (46.2Gy at 2.2 Gy/fraction) were delivered to the tumor while minimizing dose to SPECT-defined functional lung. The plan was then adapted for the final 9 fractions (2.2-3.8Gy/fraction) up to a total of 80.4Gy, based on mid-treatment FDG-PET tumor response to escalate dose to residual tumor while minimizing dose to SPECT-defined functional lung. Non-progressing patients received consolidative carboplatin/paclitaxel or durvalumab. The primary endpoint of the study was ≥ grade 2 lung and esophageal toxicities. Secondary endpoints included time to local progression, tumor response, and overall survival. ResultsAt one year post-treatment, the rates of grade 2 and grade 3 pneumonitis were 21.3% and 2.1%, respectively, with no difference in pneumonitis rates among patients who received and did not receive adjuvant durvalumab (p=0.74). While there were no grade 3 esophageal-related toxicities, 66.0% of patients experienced grade 2 esophagitis. 1- and 2-year local control rates were 94.5% (95% CI, 87.4% - 100%) and 87.5% (95% CI, 76.7% - 100%), respectively. Overall survival was 82.8% (95% CI, 72.6% -94.4%) at 1 year and 62.3% (95% CI, 49.6%-78.3%) at 2 years. ConclusionsResponse-based adaptive dose-escalation accounting for tumor change and normal tissue function during treatment provided excellent local control, comparable toxicity to standard chemoradiation, and did not increase toxicity with adjuvant immunotherapy.

Reirradiation of metastases of the central nervous system: part 2-metastatic epidural spinal cord compression.

An increasing number of patients irradiated for metastatic epidural spinal cord compression (MESCC) experience an in-field recurrence and require a second course of radiotherapy. Reirradiation can be performed with conventional radiotherapy or highly-conformal techniques such as intensity-modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT), and stereotactic body radiation therapy (SBRT). When using conventional radiotherapy, a cumulative biologically effective dose (BED) ≤120 calculated with an α/β value of 2 Gy (Gy2) was not associated with radiation myelopathy in a retrospective study of 124 patients and is considered safe. In that study, conventional reirradiation led to improvements of motor deficits in 36% of patients and stopped further symptomatic progression in another 50% (overall response 86%). In four other studies, overall response rates were 82-89%. In addition to the cumulative BED or equivalent dose in 2 Gy fractions (EQD2), the interval between both radiotherapy courses <6 months and a BED per course ≥102 Gy2 (corresponding to an EQD2 ≥51 Gy2) were identified as risk factors for radiation myelopathy. Without these risk factors, a BED >120 Gy2 may be possible. Scoring tools have been developed that can assist physicians in estimating the risk of radiation myelopathy and selecting the appropriate dose-fractionation regimen of re-treatment. Reirradiation of MESCC may also be performed with highly-conformal radiotherapy. With IMRT or VMAT, rates of pain relief and improvement of neurologic symptoms of 60-93.5% and 42-73%, respectively, were achieved. One-year local control rates ranged between 55% and 88%. Rates of myelopathy or radiculopathy and vertebral compression fractures were 0% and 0-9.3%, respectively. With SBRT, rates of pain relief were 65-86%. Two studies reported improvements in neurologic symptoms of 0% and 82%, respectively. One-year local control rates were 74-83%. Rates of myelopathy or radiculopathy and vertebral compression fractures were 0-4.5% and 4.5-13.8%, respectively. For SBRT, a cumulative maximum EQD2 to thecal sac ≤70 Gy2, a maximum EQD2 of SBRT ≤25 Gy2, a ratio ≤0.5 of thecal sac maximum EQD2 of SBRT to maximum cumulative EQD2, and an interval between both courses ≥5 months were associated with a lower risk of myelopathy. Additional prospective trials are required to better define the options of reirradiation of MESCC.

Reirradiation of metastases of the central nervous system: part 1-brain metastasis.

Because of improved survival of cancer patients, more patients irradiated for brain metastases develop intracerebral recurrences requiring subsequent courses of radiotherapy. Five studies focused on reirradiation with whole-brain radiation therapy (WBRT) after initial WBRT for brain metastases. Following the second WBRT course, improvement of clinical symptoms was found in 31-68% of patients. Rates of neurotoxicity, such as encephalopathy or cognitive decline, were reported in two studies (1.4% and 32%). In another study, severe or unexpected adverse events were not observed. Survival following the second WBRT course was generally poor, with median survival times of 2.9-4.1 months. The survival prognosis of patients receiving two courses of WBRT can be estimated by a scoring tool considering five prognostic factors. Three studies investigated reirradiation with single-fraction stereotactic radiosurgery (SF-SRS) following primary WBRT. One-year local control rates were 74-91%, and median survival times ranged between 7.8 and 14 months. Rates of radiation necrosis (RN) after reirradiation were 0-6%. Seven studies were considered that investigated re-treatment with SF-SRS or fractionated stereotactic radiation therapy (FSRT) following initial SF-SRS or FSRT. One-year local control rates were 60-88%, and the median survival times ranged between 8.3 and 25 months. During follow-up after reirradiation, rates of overall (asymptomatic or symptomatic) RN ranged between 12.5% and 30.4%. Symptomatic RN occurred in 4.3% to 23.9% of cases (patients or lesions). The risk of RN associated with symptoms and/or requiring surgery or corticosteroids appears lower after reirradiation with FSRT when compared to SF-SRS. Other potential risk factors of RN include the volume of overlap of normal tissue receiving 12 Gy at the first course and 18 Gy at the second course of SF-SRS, maximum doses ≥40 Gy of the first or the second SF-SRS courses, V12 Gy >9 cm3 of the second course, initial treatment with SF-SRS, volume of normal brain receiving 5 Gy during reirradiation with FSRT, and systemic treatment. Cumulative EQD2 ≤100-120 Gy2 to brain, <100 Gy2 to brainstem, and <75 Gy2 to chiasm and optic nerves may be considered safe. Since most studies were retrospective in nature, prospective trials are required to better define safety and efficacy of reirradiation for recurrent or progressive brain metastases.

RADIOTHERAPY OF RECURRENT SPINAL EPENDYMOMA

Spinal ependymoma is a rare tumor for which there is no consensus on optimal treatment and prognosis. However, complete resection is generally recommended when possible, offering a high rate of local control and favorable long-term survival. In cases where complete resection is not feasible, adjuvant radiotherapy may be considered to reduce the risk of recurrence. A 36-year-old patient, with no prior medical history, was diagnosed with a grade II spinal ependymoma according to the 2021 WHO classification. He underwent total resection in 2021. Twenty-one months later, he experienced a local recurrence and a spinal metastasis, for which he underwent partial resection urgently due to a sudden onset of spinal cord compression symptoms. The patient then received adjuvant radiotherapy, with a total dose of 39.6 Gy and a boost of 14.4 Gy. His pain improved starting from the second week of radiotherapy. One year later, his clinical and radiological condition remains stable.

A single-center experience of the upright proton therapy for skull-base chordomas and chondrosarcomas: Updated results

AimTo access efficacy and safety of the upright proton therapy for the skull-base chordomas and chondrosarcomas. Materials and methodsThe study encompasses single-center experience of proton therapy in chordomas (CA) and chondrosarcomas (CSA) of skull-base localization. We evaluate overall survival, local control and toxicity. Tumor response was assessed in accordance with RANO criteria. Treatment-related toxicity was evaluated with the help of CTCAE v 5.0 scale. ResultsProton therapy in the upright position was utilized for 51pts (patients) with CA-CSA (40 pts with chordoma and 11pts with chondrosarcoma) at the A. Tsyb Medical Radiological Research Center in 2016–2023. Median tumor volume constituted 30 cm3 (IQR (interquartile range) 15–41 cm3). Median total dose was 70 GyRBE. Median number of fractions was 35. Overall survival (OS) at 1-, 2- and 3-year rates reached 98.0 %, 88.6 % and 82.7 %, respectively. Median follow-up time was 36 months. The 1-, 2- and 3-year local control (LC) rates constituted, respectively, 98 %, 78.6 % and 66.3 %. Prior surgery showed statistically significant association with better prognosis (p = 0.023). Brainstem-to-tumor dose coverage compromise became the major pattern of LC failure (p = 0.03). The late radiation toxicity reactions included temporal lobe necrosis grade 2 in 2 pts, xerostomia grade 1 in 1pt, radiation cataract grade 2 in 1pt and persistent headache grade 2 in 4 pts. Severe late toxicity reactions were observed in 2 cases (4 %): 1 myelitis grade 3 and brainstem damage grade 5 in 1pt. ConclusionLocal control was achieved in the majority of patients receiving the scanning-beam upright proton therapy for skull-base CA-CSA. The LC rates after a surgery-radiotherapy combination treatment were higher compared with irradiation alone. Pattern of failure is mostly brainstem-tumor dose compromise. The high OS and LC rates were accompanied by low toxicity incidence. Even in complex case of the skull base CA-CSA upright proton therapy shows promising clinical outcomes.

Safety of propofol sedation administered by interventional radiologists for radiofrequency ablation in patients with hepatocellular carcinoma

PurposeTo evaluate the safety of propofol sedation administered by interventional radiologists during radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).Materials and methodsPropofol sedation was administered by interventional radiologists in 72 patients (85 procedures, 93 tumors) during RFA for HCC between August 2018 and December 2020. Interventional radiologists equipped with adequate knowledge and skills in sedation and respiratory management were responsible for sedation. Sedation was carefully assessed based on vital signs, including end-tidal carbon dioxide, consciousness status, and bispectral index. The primary endpoint was the incidence of sedation-related complications, which were evaluated separately as respiratory and cardiovascular complications. Secondary endpoints were technical success rate, ablation-related complications, and local tumor control rate. Technical success was defined as completion of ablation in the planned area. Complications were evaluated using the Clavien–Dindo classification. Sedation-related complications, technical success rate, and ablation-related complications were evaluated on a procedure basis, and local tumor control was evaluated on a tumor basis.ResultsRespiratory and cardiovascular complications were observed in eight (8/85, 9.4%) and two (2/85, 2.4%) patients, respectively. Four patients required the jaw thrust maneuver due to glossoptosis, whereas a decrease in oxygen saturation to < 90% was recorded in the other four patients. However, these were temporary, and none required manual ventilation or endotracheal intubation. Bradycardia (< 50 bpm) was detected in two patients; one recovered immediately without treatment, whereas the other rapidly improved after atropine sulfate administration. No severe hypotension (< 80 mmHg) was observed. The technical success rate was 100% (85/85). Grade 3 ablation-related complications were identified in three patients (3/85, 3.5%). The local tumor control rate was 95.7% (89/93).ConclusionPropofol sedation can be safely administered by interventional radiologists during RFA for HCC. Although it requires special safety considerations, it may be a sedation option during hepatic RFA.

Clinical Outcomes of Use of the Porous Glass Membrane Pumping Emulsification Device During Transarterial Chemoembolization for Hepatocellular Carcinoma.

The porous glass membrane pumping emulsification device enhances local therapeutic effects of transarterial chemoembolization for hepatocellular carcinoma (HCC); however, limited clinical outcomes have been reported. This study aimed to investigate the efficacy and safety of transarterial chemoembolization using the glass membrane pumping emulsification device for HCC. Between 2019 and 2023, 58 patients (median age=73 years) with unresectable HCC underwent 73 transarterial chemoembolizations using the glass membrane pumping emulsification device at the Nagoya University Hospital. Treatment effects were assessed using contrast-enhanced computed tomography 1-3 months after therapy and every 2-3 months thereafter. The median size of treated tumors was 25.5 mm (45 solitary nodules). The median dosage of ethiodized oil mixed with the epirubicin solution was 3 ml. Complete and partial response were observed in 73% and 11% of patients, respectively. Local control rates at 6 and 12 months were 82.8% and 59.8%, respectively. The median time to recurrence after treatment was 581 days. No major treatment-related complications occurred. The number of tumors and therapeutic effects of the initial transarterial chemoembolization were significantly associated with better local control. The glass membrane pumping emulsification device facilitated the accumulation of more concentrated ethiodized oil within the tumor and effective local control.

Predictive Factors and the Role of Conventionally Fractionated Radiation Therapy for Bone Metastasis from Renal Cell Carcinoma in the Era of Targeted Therapy.

Background and Objectives: Despite rapid advances in targeted therapies for renal cell carcinoma (RCC), bone metastases remain a major problem that significantly increases morbidity and reduces patients' quality of life. Conventional fractionated radiotherapy (CF-RT) is known to be an important local treatment option for bone metastases; however, bone metastases from RCC have traditionally been considered resistant to CF-RT. We aimed to investigate the effectiveness of CF-RT for symptomatic bone metastasis from RCC and identify the predictive factors associated with treatment outcomes in the targeted therapy era. Materials and Methods: Between January 2011 and December 2023, a total of 73 lesions in 50 patients treated with a palliative course of CF-RT for symptomatic bone metastasis from RCC were evaluated, and 62 lesions in 41 patients were included in this study. Forty-five lesions (72.6%) were treated using targeted therapy during CF-RT. The most common radiation dose fractionations were 30 gray (Gy) in 10 fractions (50%) and 39 Gy in 13 fractions (16.1%). Results: Pain relief was experienced in 51 of 62 lesions (82.3%), and the 12-month local control (LC) rate was 61.2%. Notably, 72.6% of the treatment course in this study was combined with targeted therapy. The 12-month LC rate was 74.8% in patients who received targeted therapy and only 10.9% in patients without targeted therapy (p < 0.001). Favorable Eastern Cooperative Oncology Group performance status (p = 0.026) and pain response (p < 0.001) were independent predictors of improved LC. Radiation dose escalation improved the LC in radiosensitive patients. A consistent treatment response was confirmed in patients with multiple treatment courses. Conclusions: CF-RT enhances pain relief and LC when combined with targeted therapy. Patients who responded well to initial treatment generally showed consistent responses to subsequent CF-RT for additional painful bone lesions. CF-RT could therefore be an excellent complementary local treatment modality for targeted therapy.

Treatment Outcomes of Stereotactic Body Radiotherapy for Early-stage Non-small Cell Lung Cancer and Lung Metastasis

Background and rationale: Stereotactic body radiotherapy (SBRT) is a highly precise localized high-dose per fraction radiation treatment used mainly in lung cancer. Despite SBRT's increasing use, no clear predictive factors of outcome exist. Objectives: To report local control rates, patterns of failure, and incidence of treatment-related toxicity, and to determine factors predicting SBRT outcomes for primary and secondary lung tumors at Ramathibodi Hospital using competing risk analysis. Materials and methods: This retrospective study included all patients diagnosed with primary early non-small cell lung cancer (NSCLC) and lung metastasis in our radiosurgery and radiotherapy database registry between January 2009 and September 2018. Results: Fifty-nine patients (98 lung tumors) were studied; primary NSCLC and lung metastasis were 15.3% and 84.7%, respectively. Median follow-up was 16.8 months. The overall 1-year local control rate was 90.8%. The most common pattern of failure was distant failure (46.9%). The incidence of radiation pneumonitis (RP) grade ≥2 was 9.2%, and one of four patients with an ultra-central tumor developed grade 5 pulmonary toxicity. The predictive factor for local failure was the mean biological equivalent dose (BED) of the planning target volume (PTV), and for RP grade ≥2, the tumor's maximal diameter. BED PTV mean &lt;100 Gy had higher local failure than BED PTV mean ≥100 Gy (adjusted subdistribution hazard ratio 8.26; 95% confidence interval (CI) 1.76–38.68, p=0.007). Patients with tumors with maximal diameters ≥5 cm compared with those with maximal diameters &lt;5 cm had more RP grade ≥2 (adjusted subdistribution hazard ratio 5.34; 95% CI 1.52–18.69, p=0.009). The overall 1-year survival rate was 73.5%. Conclusions: Local control of lung tumors using SBRT was high with acceptable toxicity. BED PTV mean was a local control predictor. Large tumors correlated with symptomatic RP grade ≥2. SBRT should be used judiciously for ultra-central lung tumors.

The Role of CyberKnife Stereotactic Radiosurgery in Recurrent Cranial Medulloblastomas across Pediatric and Adult Populations.

Background/Objectives: Medulloblastoma is the most common malignant brain tumor in children. In recent decades, the therapeutic landscape has undergone significant changes, with stereotactic radiosurgery (SRS) emerging as a promising treatment for recurrent cases. Our study provides a comprehensive analysis of the long-term efficacy and safety of SRS in recurrent medulloblastomas across both pediatric and adult patients at a single institution. Methods: We retrospectively reviewed the clinical and radiological records of patients who underwent CyberKnife SRS for recurrent cranial medulloblastomas at our institution between 1998 and 2023. Follow-up data were available for 15 medulloblastomas in 10 patients. The cohort comprised eight pediatric patients (ages 3-18) and two adult patients (ages 19-75). The median age at the time of SRS was 13 years, the median tumor volume accounted for 1.9 cc, the median biologically equivalent dose (BED) was 126 Gy, and the single-fraction equivalent dose (SFED) was 18 Gy. The SRS was administered at 75% of the median isodose line. Results: Following a median follow-up of 39 months (range: 6-78), 53.3% of the medulloblastomas progressed, 13.3% regressed, and 33.3% remained stable. The 3-year local tumor control (LTC) rate for all medulloblastomas was 65%, with lower rates observed in the adult cohort (50%) and higher rates in pediatric patients (67%). The 3-year overall survival (OS) rate was 70%, with significantly higher rates in pediatric patients (75%) compared to adult patients (50%). The 3-year progression-free survival (PFS) rate was 58.3%, with higher rates in pediatric patients (60%) compared to adult patients (50%). Two pediatric patients developed radiation-induced edema, while two adult patients experienced radiation necrosis at the latest follow-up, with both adult patients passing away. Conclusions: Our study provides a complex perspective on the efficacy and safety of CyberKnife SRS in treating recurrent cranial medulloblastomas across pediatric and adult populations. The rarity of adverse radiation events (AREs) underscores the safety profile of SRS, reinforcing its role in enhancing treatment outcomes. The intricacies of symptomatic outcomes, intertwined with factors such as age, tumor location, and prior surgeries, emphasize the need for personalized treatment approaches. Our findings underscore the imperative for ongoing research and the development of more refined treatment strategies for recurrent medulloblastomas. Given the observed disparities in treatment outcomes, a more meticulous tailoring of treatment approaches becomes crucial.

Clinical Outcomes of Online Adaptive Magnetic Resonance-Guided Stereotactic Body Radiotherapy of Adrenal Metastases from a Single Institution.

(1) Background: Recent publications foster stereotactic body radiotherapy (SBRT) in patients with adrenal oligometastases or oligoprogression. However, local control (LC) after non-adaptive SBRT shows the potential for improvement. Online adaptive MR-guided SBRT (MRgSBRT) improves tumor coverage and organ-at-risk (OAR) sparing. Long-term results of adaptive MRgSBRT are still sparse. (2) Methods: Adaptive MRgSBRT was performed on a 0.35 T MR-Linac. LC, overall survival (OS), progression-free survival (PFS), overall response rate (ORR), and toxicity were assessed. (3) Results: 35 patients with 40 adrenal metastases were analyzed. The median gross tumor volume was 30.6 cc. The most common regimen was 10 fractions at 5 Gy. The median biologically effective dose (BED10) was 75.0 Gy. Plan adaptation was performed in 98% of all fractions. The median follow-up was 7.9 months. One local failure occurred after 16.6 months, resulting in estimated LC rates of 100% at one year and 90% at two years. ORR was 67.5%. The median OS was 22.4 months, and the median PFS was 5.1 months. No toxicity > CTCAE grade 2 occurred. (4) Conclusions: LC and ORR after adrenal adaptive MRgSBRT were excellent, even in a cohort with comparably large metastases. A BED10 of 75 Gy seems sufficient for improved LC in comparison to non-adaptive SBRT.

Long-term outcomes after particle radiation therapy in patients with nasopharyngeal adenoid cystic carcinoma

BackgroundNasopharyngeal adenoid cystic carcinoma (NACC) is a relatively rare salivary gland tumor that is generally associated with poor outcomes. High-dose radiotherapy is a key treatment for patients with NACC. This study reported the long-term efficacy and safety of particle beam radiation therapy (PBRT) for NACC.Methods and materialsTwenty-six patients with nonmetastatic NACC who received definitive PBRT alone were included in this retrospective study. The majority of patients (92.3%) had locally advanced disease. Twenty-five (96.15%) patients received intensity-modulated proton radiotherapy (IMPT) followed by a carbon ion radiotherapy (CIRT) boost, and one patient received CIRT alone. Overall survival (OS), local control (LC), regional control (RC), and distant metastasis control (DMC) rates were calculated via the Kaplan-Meier method.ResultsThe median follow-up time was 46.95 months for the entire cohort. Seven patients experienced local recurrence, and one patient experience neck lymph node recurrence. The 3- and 4-year OS, LC, RC, and DMC rates were 100% and 91.7%, 92.3% and 84.6%, 95.8% and 87.8%, and 90.2% and 71.3%, respectively. A total of 91.3% of the patients achieved complete remission of gross tumors at 1 year after PBRT. Severe acute toxicity was observed in only two patients. A grade 4 decrease in visual acuity was observed in one patient with orbital apex invasion. No late grade 3 or 5 toxicity was observed.ConclusionDefinitive PBRT provided a satisfactory 4-year OS for patients with locally advanced NACC. The toxicity was acceptable and mild. Further follow-up is necessary to confirm the efficacy and safety of definitive PBRT for patients with NACC.

EPEN-30. PROTON THERAPY FOR PEDIATRIC INTRACRANIAL EPENDYMOMA: A SYSTEMATIC REVIEW, META-ANALYSIS AND META-REGRESSION

Abstract BACKGROUND Pediatric intracranial ependymoma (IE) represents a challenging subset of tumors necessitating tailored therapeutic strategies. Conventional treatments, including surgery and conventional radiation therapy, have shown limitations in achieving optimal outcomes, particularly in preserving neurocognitive function and mitigating long-term sequelae. Proton therapy (PT) has emerged with its ability to offer precise tumor targeting with reduced irradiation of healthy surrounding tissues. METHODS A systematic search was conducted using the electronic databases PubMed, CENTRAL, and EMBASE from inception through February 2024 following the PRISMA statement. Statistical analysis was conducted using R (R Foundation for Statistical Computing; Vienna, Austria) with the packages ‘meta’ and ‘metafor’. The random effects model of proportions was estimated using the generalized linear mixed-effects model (GLMM) method. RESULTS A total of 7 studies were included comprising 943 patients, with a mean age of 4 years, 543 boys (57.58%) and a mean dose of 56.94 Gy. The local control (LC) rate at 3 years was 83% (95% CI = 0.80 to 0.86, p=0.65) and a 5-year rate was 81% (95% CI = 0.72 to 0.89, p=0.35). Progression-free survival (PFS) was 75% at 3 years (95% CI = 0.68 to 0.82, p=0.17) and 71% at 5 years (95% CI = 0.56 to 0.87, p=0.07). Overall survival (OS) rates were notably high, with 93% at 3 years (95% CI = 0.89 to 0.97, p=0.11) and 85% at 5 years (95% CI = 0.83 to 0.87, p=0.96). Meta-regression analysis revealed that total dose significantly influenced 3-year OS (p=0.04), indicating a dose-dependent effect on survival rates. CONCLUSIONS This meta-analysis supports the effectiveness of PT through the outcomes LC, PFS and OS in pediatric IE. The significant correlation between total dose and 3-year OS underscores the importance of dose optimization in treatment planning. These findings highlight the importance of PT in pediatric neuro-oncology management, offering evidence-based guidance for enhancing therapeutic strategies and patient outcomes.