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• Critical structure constraints used in our randomized controlled trial of short-course versus conventional radiotherapy for patients with glioblastoma were appropriate for limiting grade 2 or higher toxicities. • Higher left-hippocampal mean doses were the most predictive for neuro-cognitive decline post-radiotherapy. • Routine contouring and use of dose constraints for the hippocampus is recommended. • Our left hippocampus sparing treatment model may help minimize neuro-cognitive decline in patients with glioblastoma treated with radiotherapy. There is no consensus on appropriate organ at risk (OAR) constraints for short-course radiotherapy for patients with glioblastoma. Using dosimetry and prospectively-collected toxicity data from a trial of short-course radiotherapy for glioblastoma, this study aims to empirically examine the OAR constraints, with particular attention to left hippocampus dosimetry and impact on neuro-cognitive decline. Data was taken from a randomized control trial of 133 adults (age 18–70 years; ECOG performance score 0–2) with newly diagnosed glioblastoma treated with 60 Gy in 30 (conventional arm) versus 20 (short-course arm) fractions of adjuvant chemoradiotherapy (ClinicalTrials.gov Identifier: NCT02206230). The delivered plan's dosimetry to the OARs was correlated to prospective-collected toxicity and Mini-Mental State Examination (MMSE) data. Toxicity events were not significantly increased in the short-course arm versus the conventional arm. Across all OARs, delivered radiation doses within protocol-allowable maximum doses correlated with lack of grade ≥ 2 toxicities in both arms (p < 0.001), while patients with OAR doses at or above protocol limits correlated with increased grade ≥ 2 toxicities across all examined OARs in both arms (p-values 0.063–0.250). Mean left hippocampus dose was significantly associated with post-radiotherapy decline in MMSE scores (p = 0.005), while the right hippocampus mean dose did not reach statistical significance (p = 0.277). Compared to the original clinical plan, RapidPlan left hippocampus sparing model decreased left hippocampus mean dose by 43 % (p < 0.001), without compromising planning target volume coverage. In this trial, protocol OAR constraints were appropriate for limiting grade ≥ 2 toxicities in conventional and short-course adjuvant chemoradiotherapy for glioblastoma. Higher left hippocampal mean doses were predictive for neuro-cognitive decline post-radiotherapy. Routine contouring and use of dose constraints to limit hippocampal dose is recommended to minimize neuro-cognitive decline in patients with glioblastoma treated with chemoradiotherapy. [ABSTRACT FROM AUTHOR]

Studies calcium/calmodulin-dependent protein kinase II regulation of c-FLIP expression and phosphorylation in modulation of Fas-mediated signaling in malignant glioma cells. Ability of Fas agonistic antibody CH-11 to induce apoptosis in sensitive glioma cells; Molecular mechanisms that control Fas-mediated signalin in glioma cells.

Purpose: To determine the efficacy of motexafin gadolinium (MGd) in combination with whole brain radiotherapy (WBRT) for the treatment of brain metastases from non–small-cell lung cancer. Methods and Materials: In an international, randomized, Phase III study, patients with brain metastases from non–small-cell lung cancer were randomized to WBRT with or without MGd. The primary endpoint was the interval to neurologic progression, determined by a centralized Events Review Committee who was unaware of the treatment the patients had received. Results: Of 554 patients, 275 were randomized to WBRT and 279 to WBRT+MGd. Treatment with MGd was well tolerated, and 92% of the intended doses were administered. The most common MGd-related Grade 3+ adverse events included liver function abnormalities (5.5%), asthenia (4.0%), and hypertension (4%). MGd improved the interval to neurologic progression compared with WBRT alone (15 vs. 10 months; p = 0.12, hazard ratio [HR] = 0.78) and the interval to neurocognitive progression (p = 0.057, HR = 0.78). The WBRT patients required more salvage brain surgery or radiosurgery than did the WBRT+MGd patients (54 vs. 25 salvage procedures, p < 0.001). A statistically significant interaction between the geographic region and MGd treatment effect (which was in the prespecified analysis plan) and between treatment delay and MGd treatment effect was found. In North American patients, where treatment was more prompt, a statistically significant prolongation of the interval to neurologic progression, from 8.8 months for WBRT to 24.2 months for WBRT+MGd (p = 0.004, HR = 0.53), and the interval to neurocognitive progression (p = 0.06, HR = 0.73) were observed. Conclusion: In the intent-to-treat analysis, MGd exhibited a favorable trend in neurologic outcomes. MGd significantly prolonged the interval to neurologic progression in non–small-cell lung cancer patients with brain metastases receiving prompt WBRT. The toxicity was acceptable. [Copyright &y& Elsevier]

Purpose: To evaluate prospectively the acute and late morbidities from a multiinstitutional three-dimensional radiotherapy dose-escalation study for inoperable non–small-cell lung cancer. Methods and materials: A total of 179 patients were enrolled in a Phase I–II three-dimensional radiotherapy dose-escalation trial. Of the 179 patients, 177 were eligible. The use of concurrent chemotherapy was not allowed. Twenty-five patients received neoadjuvant chemotherapy. Patients were stratified at escalating radiation dose levels depending on the percentage of the total lung volume that received >20 Gy with the treatment plan (V20). Patients with a V20 <25% (Group 1) received 70.9 Gy in 33 fractions, 77.4 Gy in 36 fractions, 83.8 Gy in 39 fractions, and 90.3 Gy in 42 fractions, successively. Patients with a V20 of 25–36% (Group 2) received doses of 70.9 Gy and 77.4 Gy, successively. The treatment arm for patients with a V20 ≥37% (Group 3) closed early secondary to poor accrual (2 patients) and the perception of excessive risk for the development of pneumonitis. Toxicities occurring or persisting beyond 90 days after the start of radiotherapy were scored as late toxicities. The estimated toxicity rates were calculated on the basis of the cumulative incidence method. Results: The following acute Grade 3 or worse toxicities were observed for Group 1: 70.9 Gy (1 case of weight loss), 77.4 Gy (nausea and hematologic toxicity in 1 case each), 83.8 Gy (1 case of hematologic toxicity), and 90.3 Gy (3 cases of lung toxicity). The following acute Grade 3 or worse toxicities were observed for Group 2: none at 70.9 Gy and 2 cases of lung toxicity at 77.4 Gy. No patients developed acute Grade 3 or worse esophageal toxicity. The estimated rate of Grade 3 or worse late lung toxicity at 18 months was 7%, 16%, 0%, and 13% for Group 1 patients receiving 70.9, 77.4, 83.8, or 90.3 Gy, respectively. Group 2 patients had an estimated late lung toxicity rate of 15% at 18 months for both 70.9 and 77.4 Gy. The prognostic factors for late pneumonitis in multivariate analysis were the mean lung dose and V20. The estimated rate of late Grade 3 or worse esophageal toxicity at 18 months was 8%, 0%, 4%, and 6%, for Group 1 patients receiving 70.9, 77.4, 83.8, 90.3 Gy, respectively, and 0% and 5%, respectively, for Group 2 patients receiving 70.9 and 77.4 Gy. The dyspnea index scoring at baseline and after therapy for functional impairment, magnitude of task, and magnitude of effort revealed no change in 63%, functional pulmonary loss in 23%, and pulmonary improvement in 14% of patients. The observed locoregional control and overall survival rates were each similar among the study arms within each dose level of Groups 1 and 2. Locoregional control was achieved in 50–78% of patients. Thirty-one patients developed regional nodal failure. The location of nodal failure in relationship to the RT volume was documented in 28 of these 31 patients. Twelve patients had isolated elective nodal failures. Fourteen patients had regional failure in irradiated nodal volumes. Two patients had both elective nodal and irradiated nodal failure. Conclusions: The radiation dose was safely escalated using three-dimensional conformal techniques to 83.8 Gy for patients with V20 values of <25% (Group 1) and to 77.4 Gy for patients with V20 values between 25% and 36% (Group 2), using fraction sizes of 2.15 Gy. The 90.3-Gy dose level was too toxic, resulting in dose-related deaths in 2 patients. Elective nodal failure occurred in <10% of patients. [Copyright &y& Elsevier]

This study investigated the dosimetric advantages of inversely planned intensity-modulated radiotherapy (IMRT) over forward-planned conventional 3D conformal radiotherapy (3D-CRT) in treating lung cancer patients at escalated dose. Three consecutively accrued patients on the RTOG 93-11 dose-escalation protocol were replanned using IMRT with the same dosimetric rules, so that the isodose distributions and dose-volume histograms could be generated and compared. The Helax-TMS treatment planning system, with an IMRT optimization module (version 6.0), was used. In all cases, a consistent approach of inverse planning and set of dose-volume constraints (DVCs) provided improved critical structure sparing. However, the minimum dose in PTV was generally below that achieved with the corresponding forward planned 3D-CRT. [Copyright &y& Elsevier]

Abstract: Intensity modulated radiation therapy (IMRT) guided by PET/CT imaging with respiratory gating was employed to dose escalate in patients with non-small cell lung cancer (NSCLC), using accelerated fractionation with induction chemotherapies. One patient developed a grade 5 pneumonitis and the study was halted at 84Gy in 35 fractions. [Copyright &y& Elsevier]