LINAC-based radiosurgery for melanoma, sarcoma and renal cell carcinoma brain metastases

Stereotactic radiotherapy for brain oligometastases

Brain metastases, the most common metastases in adults, will develop in up to 40% of cancer patients, accounting for more than one-half of all intracranial tumors. They are most associated with breast and lung cancer, melanoma and, less frequently, colorectal and kidney carcinoma.

Magnetic resonance imaging (MRI) is the gold standard for diagnosis. For the treatment plan, computed tomography (CT ) images are co-registered and fused with a gadolinium-enhanced T1-weighted MRI where tumor volume and organs at risk are contoured. Alternatively, plain and contrast-enhanced CT scans are co-registered. Single-fraction stereotactic radiotherapy (SRT ) is used to treat patients with good performance status and up to 4 lesions with a diameter of 30 mm or less that are distant from crucial brain function areas. Fractionated SRT (2–5 fractions) is used for larger lesions, in eloquent areas or in proximity to crucial or surgically inaccessible areas and to reduce treatment-related neurotoxicity. The single-fraction SRT dose, which depends on tumor diameter, impacts local control. Fractionated SRT may encompass different schedules. No randomized trial data compared the safety and efficacy of single and multiple fractions. Both single-fraction and fractionated SRT provide satisfactory local control rates, tolerance, a low risk of transient acute adverse events and of radiation necrosis the incidence of which correlated with the irradiated brain volume.

Synergistic Effects of Combined Anthocyanin and Metformin Treatment for Hyperglycemia In Vitro and In Vivo

The mechanism underlying the hypoglycemic effect of the simultaneous use of metformin and anthocyanin-rich foods is not yet clear. Hence, the effects and possible mechanisms of action of these substances, alone and in combination, were evaluated in insulin-resistant HepG2 cells and a diabetic mouse model. The results indicated that anthocyanin and metformin had a significant synergistic effect on glucose consumption (CI < 0.9) compared with metformin alone in HepG2 cells. In the mouse model, combined treatment (50 and 100 mg/kg metformin + anthocyanin groups) demonstrated synergistic restorative effects on the blood glucose level, insulin resistance, and organ damage in the liver, pancreas, and ileum. Additionally, combined metformin and anthocyanin treatment suppressed protein tyrosine phosphatase 1B expression and regulated the PI3K/AKT/GSK3β pathway. Combined treatment also altered the gut microbial composition and structure by increasing the relative abundance of beneficial bacteria and the short-chain fatty acid content. These results suggest that the use of anthocyanins can enhance the efficacy of metformin treatment for hyperglycemia and provide a reference for further clinical research regarding nutrition and supplementary treatment.

Brain Metastases and Place of Antiangiogenic Therapies in Alveolar Soft Part Sarcoma: A Retrospective Analysis of the French Sarcoma Group

BACKGROUND

Alveolar soft part sarcoma (ASPS) is a rare sarcoma characterized by a slow evolution, brain metastasis (BM), and resistance to doxorubicin. Antiangiogenic therapies (AAT) have shown clinical activity, but little is known about the optimal therapeutic strategy, specifically considering BM.

SUBJECTS, MATERIALS, AND METHODS

We performed a retrospective analysis of all patients with ASPS treated in three referral centers of the French Sarcoma Group. We aimed to describe factors associated with overall survival (OS) and the impact of BM on outcome of patients treated by AAT.

RESULTS

We identified 75 patients between 1971 and 2012 (median age = 23, range: 5-96 years). Median follow-up was 74 months. Patients with localized (n = 44, 59%) and metastatic (n = 31, 41%) diseases had a 10-year OS of 69% and 25%, respectively. Only surgical incomplete resection was associated with shorter OS in localized disease (hazard ratio [HR] = 5.2, 95% confidence interval [CI] 1.2-22.4, p = .02). Fifty-two (69%) patients developed lung metastasis (LM; baseline: n = 31, [41%]; de novo: n = 21, [28%]). Thirteen patients developed BM, all occurring after LM. Tumor size ≥5 cm was associated with poorer BM-free survival (HR = 8.4, 95% CI 2.1-33.9, p = .002). Median OS post-BM was 17 months (95% CI 15 to not assessable). Overall, 12 patients were treated with AAT (sunitinib n = 10): 5 patients had BM and achieved poor outcomes compared with patients without, with median progression-free-survivals of 2 versus 11 months, respectively.

CONCLUSION

Baseline larger tumors were associated with increased risk of brain metastasis in patients with ASPS. Patients with BM seem to have little benefit from AAT, suggesting the need to develop antineoplastic agents with high central nervous system penetrance in this setting.

IMPLICATIONS FOR PRACTICE

Alveolar soft part sarcoma (ASPS) is an extremely rare subtype of sarcoma that is particularly resistant to conventional therapies. Antiangiogenic therapies (AAT) have shown promising results. However, patients with ASPS still die of tumor evolution. This study highlights the prognostic shift induced by brain metastasis (BM), identifying this event as a major contributor to the death of patients with ASPS, and observes a striking lack of effectiveness of AAT in patients who had previously developed BM. This observation is of interest for the therapeutic development in ASPS, highlighting the need to develop strategies dedicated to BM, such as radiosurgery or high-central nervous system penetrance tyrosine kinase inhibitors.

Clinical outcomes of gastrointestinal brain metastases treated with radiotherapy

Background

Brain metastases of gastrointestinal origin are a rare occurrence. Radiation therapy (RT) in the form of stereotactic radiosurgery (SRS) or whole brain radiation therapy (WBRT) is an effective established treatment modality in either the definitive or adjuvant setting. The aim of this study is to assess the long-term clinical outcomes of patients with gastrointestinal (GI) brain metastases treated with SRS or WBRT.

Methods

In this single institutional retrospective review, we detail the outcomes of patients diagnosed with metastatic brain tumors from an adenocarcinoma gastrointestinal primary. Patients were treated using stereotactic radiosurgery or whole brain radiation therapy. Initial site control (defined as lesions visualized on imaging at time of treatment), new site control (defined as new intracranial lesions visualized on follow-up imaging), and overall survival were calculated using the Kaplan-Meier method.

Results

Thirty-three patients were treated from August 2008 to December 2015. Primary malignancy locations were as follows: 18 colon, 6 esophagus, 4 rectum, 5 other. Median total dose delivered was 25 Gy (18–35 Gy) in a median of 4 fractions for SRS and 30 Gy (10.8–40 Gy) in 10 fractions for WBRT. Crude initial site control at last radiographic follow-up was 64.3% after SRS and 41.7% after WBRT. Eleven of the 28 brain lesions (39.3%) treated with SRS had resection of the SRS-treated lesion prior to radiation therapy. Five of the twelve patients (41.7%) undergoing WBRT underwent cranial resection prior to radiation therapy. Crude new site control at last radiographic follow-up was 46.4% after SRS and 83.3% after WBRT. Kaplan-Meier analysis of overall survival did not show any statistically significant difference between WBRT and SRS (p = 0.424). Median overall survival for SRS patients was 5.2 months (0.5–57.5) and for WBRT patients 4.4 months (0–15). Kaplan-Meier analysis of new site control was significantly improved with WBRT versus SRS (p = 0.017). Total dose, treatment with WBRT, and active extracranial disease were statistically significant on multivariate analysis for new site control (p < 0.05).

Conclusions

Survival and intracranial disease control are poor following RT for brain metastases from GI primaries. In this small series, outcomes are worse than published series for other primary malignancies metastatic to the brain and further research into methods of local control improvement is warranted. Future studies should explore the utility of dose escalation or radiosensitization in this patient population.