Radiotherapy for metastatic spinal cord compression with increased radiation doses (RAMSES-01): a prospective multicenter study.

BACKGROUND: Patients with metastatic spinal cord compression (MSCC) and favorable survival prognoses can benefit from radiation doses greater than 30Gy in 10 fractions in terms of improved local progression-free survival (LPFS) and overall survival (OS). METHODS/DESIGN: This prospective study mainly investigates LPFS after precision radiotherapy (volumetric modulated arc therapy or stereotactic body radiotherapy) with 18 × 2.33Gy in 3.5 weeks. LPFS is defined as freedom from progression of motor deficits during radiotherapy and an in-field recurrence of MSCC following radiotherapy. The maximum relative dose allowed to the spinal cord is 101.5% of the prescribed dose, resulting in an equivalent dose in 2Gy-fractions (EQD2) for radiation myelopathy is 45.5Gy, which is below the tolerance dose of 50Gy according to the Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC). The EQD2 of this regimen for tumor cell kill is 43.1Gy, which is 33% higher than for 30Gy in 10 fractions (EQD2 = 32.5Gy). Primary endpoint is LPFS at 12 months after radiotherapy. Secondary endpoints include the effect of 18 × 2.33Gy on motor function, ambulatory status, sensory function, sphincter dysfunction, LPFS at other follow-up times, overall survival, pain relief, relief of distress and toxicity. Follow-up visits for all endpoints will be performed directly and at 1, 3, 6, 9 and 12 months after radiotherapy. A total of 65 patients are required for the prospective part of the study. These patients will be compared to a historical control group of at least 235 patients receiving conventional radiotherapy with 10x3Gy in 2 weeks. DISCUSSION: If precision radiotherapy with 18 × 2.33Gy results in significantly better LPFS than 10x3Gy of conventional radiotherapy, this regimen should be strongly considered for patients with MSCC and favorable survival prognoses. TRIAL REGISTRATION: Clinicaltrials.gov NCT04043156. Registered 30-07-2019.

Prospective study on stereotactic body radiotherapy for small pancreatic neuroendocrine tumors: tolerance and effectiveness analysis.

INTRODUCTION: Surgery is the standard treatment for pancreatic neuroendocrine tumors (pNETs), obtaining favorable results but associating high morbidity and mortality rates. This study assesses stereotactic body radiation therapy (SBRT) as a radical approach for small (< 2 cm) nonfunctioning pNETs. MATERIALS AND METHODS: From January 2017 to June 2023, 20 patients with small pNETs underwent SBRT in an IRB-approved study. Endpoints included local control, tolerance, progression-free survival, and overall survival (OS). Diagnostic assessments comprised endoscopy, CT scans, OctreScan or PET-Dotatoc, abdominal MRI, and histological confirmatory samples. RESULTS: In a 30-month follow-up of 20 patients (median age 55.5 years), SBRT was well-tolerated with no grade > 2 toxicity. 40% showed morphological response, 55% remained stable. Metabolically, 50% achieved significant improvement. With a median OS of 41.5 months, all patients were alive without local or distant progression or need for surgical resection. CONCLUSION: SBRT is a feasible and well-tolerated approach for small neuroendocrine pancreatic tumors, demonstrating effective local control. Further investigations are vital for validation and extension of these findings.

Precision Radiation Therapy for Metastatic Spinal Cord Compression: Final Results of the PRE-MODE Trial.

OBJECTIVE: To investigate precision radiation therapy for metastatic spinal cord compression and compare it to conventional radiation therapy. METHODS AND MATERIALS: In a multicenter phase 2 study, 40 patients received 5 Gy × 5 fractions of precision radiation therapy (38 volume modulated arc therapy, 2 intensity modulated radiation therapy) for metastatic spinal cord compression and were evaluated for local progression-free survival (LPFS), motor function, ambulatory status, sensory function, sphincter dysfunction, pain, distress, overall survival (OS), and toxicity. Maximum spinal cord dose was 101.5% (myelopathy risk, <0.03%) of the prescription dose. Patients were compared with a historical control group conventionally irradiated with 4 Gy × 5 fractions (propensity score analysis). The equivalent dose in 2 Gy-fractions of 5 Gy × 5 fractions is similar to 3 Gy × 10 fractions, which results in better LPFS than 4 Gy × 5 fractions. It was assumed that 5 Gy × 5 fractions is also superior to 4 Gy × 5 fractions for LPFS. (ClinicalTrials.gov-identifier: NCT03070431) RESULTS: Six-month rates of LPFS and OS were 95.0% and 42.6%, respectively. Improvement of motor function occurred in 24 patients (60%). Thirty-three patients (82.5%) were ambulatory after radiation therapy. Eight of 16 patients (50.0%) with sensory deficits improved. Pain and distress relief were reported by 61.9% and 54.2% of patients 1 month after radiation therapy. Grade 3 toxicities occurred in 1 patient and grade 2 toxicities in another 3 patients. Of the control group, 664 patients qualified for the propensity score analysis; 5 Gy × 5 fractions was significantly superior to 4 Gy × 5 fractions with regard to LPFS (P = .026) but not motor function (P = .51) or OS (P = .82). CONCLUSIONS: Precision radiation therapy with 5 Gy × 5 fractions was well tolerated and effective and appeared superior to 4 Gy × 5 fractions in terms of LPFS. The retrospective nature of the historic control group, which might have led to a hidden selection bias, needs to be considered when interpreting the results.