Fractionated stereotactic radiation therapy for intact brain metastases

Purpose: Limited data exist on fractionated stereotactic radiation therapy (FSRT) for brain metastases. We sought to evaluate the safety and efficacy of FSRT and further define its role in brain metastasis management. Methods and materials: A total of 72 patients were treated with linear accelerator–based FSRT to 182 previously untreated, intact brain metastases. Targets received 25 or 30 Gy in 5 fractions. All targets within the same course received the same prescription regardless of size. Toxicity was recorded per Radiation Therapy Oncology Group central nervous system toxicity criteria. Results: The median follow-up was 5 months (range, 1-71 months). The Kaplan-Meier estimate of 12-month local control was 86%. Tumors <3 cm in diameter demonstrated improved 12-month local control of 95% compared with 61% in tumors ≥3 cm (P < .001). The Kaplan-Meier estimate of 12-month local control was 91% in tumors treated with 30 Gy and only 75% in tumors treated with 25 Gy (P = .015). Tumor diameter ≥3 cm resulted in increased local failure, and a 30 Gy prescription resulted in decreased local failure on multivariate analysis (hazard ratio [HR], 8.11 [range, 2.09-31.50; P = .003] and HR, 0.26 [range, 0.07-0.93; P = .038]). Grade 4 central nervous system toxicity occurred in 4 patients (6%) requiring surgery, and no patient experienced irreversible grade 3 or 5 toxicity. Increasing tumor diameter was associated with increased toxicity risk (HR, 2.45 [range, 1.04-5.742; P = .04]). Conclusions: FSRT for brain metastases appears to demonstrate a high rate of local control with minimal risk of severe toxicity. Local control appears to be associated with smaller tumor sizeand a higher prescription dose. FSRT is a viable option for those who are poor single-fraction candidates

Regulation of heparin-binding EGF-like growth factor by miR-212 and acquired cetuximab-resistance in head and neck squamous cell carcinoma.

We hypothesized that chronic inhibition of epidermal growth factor receptor (EGFR) by cetuximab, a monoclonal anti-EGFR antibody, induces up-regulation of its ligands resulting in resistance and that microRNAs (miRs) play an important role in the ligand regulation in head and neck squamous cell carcinoma (HNSCC).Genome-wide changes in gene and miR expression were determined in cetuximab-sensitive cell line, SCC1, and its resistant derivative 1Cc8 using DNA microarrays and RT-PCR. The effects of differentially expressed EGFR ligands and miRs were examined by MTS, colony formation, ELISA, and western blot assays. Heparin-binding EGF-like growth factor (HB-EGF) and its regulator, miR-212, were differentially expressed with statistical significance when SCC1 and 1Cc8 were compared for gene and miR expression. Stimulation with HB-EGF induced cetuximab resistance in sensitive cell lines. Inhibition of HB-EGF and the addition of miR-212 mimic induced cetuximab sensitivity in resistant cell lines. MicroRNA-212 and HB-EGF expression were inversely correlated in an additional 33 HNSCC and keratinocyte cell lines. Six tumors and 46 plasma samples from HNSCC patients were examined for HB-EGF levels. HB-EGF plasma levels were lower in newly diagnosed HNSCC patients when compared to patients with recurrent disease.Increased expression of HB-EGF due to down-regulation of miR-212 is a possible mechanism of cetuximab resistance. The combination of EGFR ligand inhibitors or miR modulators with cetuximab may improve the clinical outcome of cetuximab therapy in HNSCC

Body composition and mortality in men receiving prostate radiotherapy: A pooled analysis of NRG/RTOG 9406 and NRG/RTOG 0126.

PURPOSE: To validate the association between body composition and mortality in men treated with radiation for localized prostate cancer (PCa). Secondarily, to integrate body composition as a factor to classify patients by risk of all-cause mortality. MATERIALS AND METHODS: Participants of NRG/Radiation Therapy Oncology Group (RTOG) 9406 and NRG/RTOG 0126 with archived computed tomography were included. Muscle mass and muscle density were estimated by measuring the area and attenuation of the psoas muscles on a single slice at L4-L5. Bone density was estimated by measuring the attenuation of the vertebral body at mid-L5. Survival analyses, including Cox proportional hazards models, assessed the relationship between body composition and mortality. Recursive partitioning analysis (RPA) was used to create a classification tree to classify participants by risk of death. RESULTS: Data from 2066 men were included in this study. In the final multivariable model, psoas area, comorbidity score, baseline prostate serum antigen, and age were significantly associated with survival. The RPA yielded a classification tree with four prognostic groups determined by age, comorbidity, and psoas area. Notably, the classification among older (≥70&nbsp;years) men into prognostic groups was determined by psoas area. CONCLUSIONS: This study strongly supports that body composition is related to mortality in men with localized PCa. The inclusion of psoas area in the RPA classification tree suggests that body composition provides additive information to age and comorbidity status for mortality prediction, particularly among older men. More research is needed to determine the clinical impact of body composition on prognostic models in men with PCa

A competing risk nomogram to predict severe late toxicity after modern re-irradiation for squamous carcinoma of the head and neck

PURPOSE: Severe late toxicity is common after re-irradiation for recurrent or second primary (RSP) squamous carcinoma of the head and neck. However, many patients experience complications from tumor progression before manifesting late effects. We constructed a nomogram to examine this relationship between late toxicity and competing risks. METHODS AND MATERIALS: Patients with RSP squamous carcinoma originating in a field previously irradiated to ≥40 Gy and treated with IMRT-based re-irradiation to ≥40 Gy were collected. Grade ≥3 late toxicity developing ≥90 days after re-irradiation was collected. A multivariable competing-risk model was fit to the actuarial risk of late toxicity with progression or death as the competing risk. The final bootstrap optimized model was converted into a nomogram. RESULTS: From 9 institutions, 505 patients were included. The 2-year incidence of grade ≥3 late toxicity was 16.7% (95% CI 13.2-20.2%) whereas progression or death was 64.2% (95% CI 59.7-68.8%). The median freedom from late toxicity, progression or death was 10.7, 5.5 and 3.2 months for RPA class I-III patients respectively, whereas the median OS was 44.9, 15.9 and 7.9 months, respectively. The final model included six clinical factors. Notably, dose, volume and fractionation did not significantly impact toxicity. CONCLUSIONS: After re-irradiation, the risk of progression or death is approximately four times the risk of radiation-related severe late toxicity. The risk of late toxicity may be more dependent on patient and disease factors than modifiable treatment factors. This model is useful for patient selection, pre-treatment consent and post-treatment survivorship following re-irradiation

Volume, Dose, and Fractionation Considerations for IMRT-based Reirradiation in Head and Neck Cancer: A Multi-institution Analysis

PURPOSE: Limited data exist to guide the treatment technique for reirradiation of recurrent or second primary squamous carcinoma of the head and neck. We performed a multi-institution retrospective cohort study to investigate the effect of the elective treatment volume, dose, and fractionation on outcomes and toxicity. METHODS AND MATERIALS: Patients with recurrent or second primary squamous carcinoma originating in a previously irradiated field (≥40 Gy) who had undergone reirradiation with intensity modulated radiation therapy (IMRT); (≥40 Gy re-IMRT) were included. The effect of elective nodal treatment, dose, and fractionation on overall survival (OS), locoregional control, and acute and late toxicity were assessed. The Kaplan-Meier and Gray\u27s competing risks methods were used for actuarial endpoints. RESULTS: From 8 institutions, 505 patients were included in the present updated analysis. The elective neck was not treated in 56.4% of patients. The median dose of re-IMRT was 60 Gy (range 39.6-79.2). Hyperfractionation was used in 20.2%. Systemic therapy was integrated for 77.4% of patients. Elective nodal radiation therapy did not appear to decrease the risk of locoregional failure (LRF) or improve the OS rate. Doses of ≥66 Gy were associated with improvements in both LRF and OS in the definitive re-IMRT setting. However, dose did not obviously affect LRF or OS in the postoperative re-IMRT setting. Hyperfractionation was not associated with improved LRF or OS. The rate of acute grade ≥3 toxicity was 22.1% overall. On multivariable logistic regression, elective neck irradiation was associated with increased acute toxicity in the postoperative setting. The rate of overall late grade ≥3 toxicity was 16.7%, with patients treated postoperatively with hyperfractionation experiencing the highest rates. CONCLUSIONS: Doses of ≥66 Gy might be associated with improved outcomes in high-performance patients undergoing definitive re-IMRT. Postoperatively, doses of 50 to 66 Gy appear adequate after removal of gross disease. Hyperfractionation and elective neck irradiation were not associated with an obvious benefit and might increase toxicity

Body composition and mortality in men receiving prostate radiotherapy: A pooled analysis of NRG/RTOG 9406 and NRG/RTOG 0126

PurposeTo validate the association between body composition and mortality in men treated with radiation for localized prostate cancer (PCa). Secondarily, to integrate body composition as a factor to classify patients by risk of all-cause mortality.Materials and MethodsParticipants of NRG/Radiation Therapy Oncology Group (RTOG) 9406 and NRG/RTOG 0126 with archived computed tomography were included. Muscle mass and muscle density were estimated by measuring the area and attenuation of the psoas muscles on a single slice at L4–L5. Bone density was estimated by measuring the attenuation of the vertebral body at mid-L5. Survival analyses, including Cox proportional hazards models, assessed the relationship between body composition and mortality. Recursive partitioning analysis (RPA) was used to create a classification tree to classify participants by risk of death.ResultsData from 2066 men were included in this study. In the final multivariable model, psoas area, comorbidity score, baseline prostate serum antigen, and age were significantly associated with survival. The RPA yielded a classification tree with four prognostic groups determined by age, comorbidity, and psoas area. Notably, the classification among older (≥70 years) men into prognostic groups was determined by psoas area.ConclusionsThis study strongly supports that body composition is related to mortality in men with localized PCa. The inclusion of psoas area in the RPA classification tree suggests that body composition provides additive information to age and comorbidity status for mortality prediction, particularly among older men. More research is needed to determine the clinical impact of body composition on prognostic models in men with PCa.This study strongly supports that body composition is related to mortality in men with localized prostate cancer. The inclusion of psoas area in the recursive partitioning analysis classification tree suggests that body composition provides additive information to age and comorbidity status for mortality prediction, particularly among older men.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/175907/1/cncr34596_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/175907/2/cncr34596.pd