Long-term outcomes and prognostic factors of skull-base chondrosarcoma patients treated with pencil-beam scanning proton therapy at the Paul Scherrer Institute

Background

Skull-base chondrosarcoma (ChSa) is a rare disease, and the prognostication of this disease entity is ill defined.

Methods

We assessed the long-term local control (LC) results, overall survival (OS), and prognostic factors of skull-base ChSa patients treated with pencil beam scanning proton therapy (PBS PT). Seventy-seven (male, 35; 46%) patients with histologically confirmed ChSa were treated at the Paul Scherrer Institute. Median age was 38.9 years (range, 10.2–70.0y). Median delivered dose was 70.0 Gy_RBE (range, 64.0–76.0 Gy_RBE). LC, OS, and toxicity-free survival (TFS) rates were calculated using the Kaplan Meier method.

Results

After a mean follow-up of 69.2 months (range, 4.6–190.8 mo), 6 local (7.8%) failures were observed, 2 of which were late failures. Five (6.5%) patients died. The actuarial 8-year LC and OS were 89.7% and 93.5%, respectively. Tumor volume > 25 cm³ (P = .02), brainstem/optic apparatus compression at the time of PT (P = .04) and age >30 years (P = .08) were associated with lower rates of LC. High-grade (≥3) radiation-induced toxicity was observed in 6 (7.8%) patients. The 8-year high-grade TFS was 90.8%. A higher rate of high-grade toxicity was observed for older patients (P = .073), those with larger tumor volume (P = .069), and those treated with 5 weekly fractions (P = .069).

Conclusions

This is the largest PT series reporting the outcome of patients with low-grade ChSa of the skull base treated with PBS only. Our data indicate that protons are both safe and effective. Tumor volume, brainstem/optic apparatus compression, and age were prognosticators of local failures.     

Hypofractionated regional nodal irradiation for breast cancer: Examining the data and potential for future studies

Limited data are available examining the role of hypofractionated radiation schedules in the management of women requiring regional nodal irradiation (RNI). The purpose of this review is to examine the available literature for the efficacy (where available) and toxicity of hypofractionated radiation schedules in breast cancer with RNI limited to the axilla and supraclavicular regions. Multiple randomized and prospective studies have documented the safety and efficacy of hypofractionated schedules delivering whole breast irradiation (WBI) alone. Subsets from these randomized trials and smaller prospective/single-institution studies have documented the feasibility of hypofractionated RNI but the limited numbers prevent definitive conclusions and limited efficacy data are available. With regard to possible toxicity affecting organs at risk with RNI, key structures include the breast, skin, heart, lungs, axilla (lymphedema), and brachial plexus. Based on data from several randomized trials, hypofractionated radiation is not associated with significant changes in breast toxicity/cosmesis or cardiac toxicity; the addition of hypofractionated RNI would not be expected to change the rates of breast or cardiac toxicity. While RNI has been shown to increase rates of pulmonary toxicity, hypofractionated RNI has not been associated with more frequent pulmonary complications than standard RNI. Moving forward, future studies will have to evaluate for increased lung toxicity. With regard to lymphedema, data from randomized hypofractionated WBI trials failed to demonstrate an increase in lymphedema and smaller studies utilizing hypofractionated RNI have failed to as well. Data from head and neck cancer as well as hypofractionated breast radiation with RNI have failed to demonstrate an increase in brachial plexopathy with the exception of older trials that used much larger dose per fraction (>4 Gy/fraction) schedules. At this time, published data support the feasibility of hypofractionated RNI and the need for a prospective randomized trial addressing clinical outcomes and toxicity of hypofractionated RNI compared with standard fractionation RNI.     

Drimane-type sesquiterpenes from Polygonum hydropiper

One new drimane-type sesquiterpenoid, 3 β-angeloyloxy-7-epifutronolide (1), and one new natural product, polygonumate (2), along with six known drimane-type sesquiterpenes [dendocarbin L (3), (+) winterin (4), (+) fuegin (5), changweikangic acid A (6), futronolide (7), and 7-ketoisodrimenin (8)] were isolated from the whole plant of Polygonum hydropiper Linn. Their structures were determined using spectroscopic techniques. Single-crystal X-ray diffraction study on dendocarbin L (3) and 13C-NMR spectroscopic data of (+) winterin (4) are described for the first time. Compound 6 was evaluated for inhibitions of α-chymotrypsin, acetylcholinesterase, and butyrylcholinesterase enzymes.     

Exploring the relationship between essential tremor and Parkinson's disease

Although essential tremor (ET) and Parkinson's disease (PD) are considered distinct disorders, there is overlap in some clinical features. In some PD patients, a long-standing postural tremor in the hands may precede the onset of parkinsonian features by several years or decades. Furthermore, large families with both ET and PD phenotypes have been described and autopsy studies have demonstrated Lewy body pathology in brains of ET patients. Functional neuroimaging suggests that some ET patients have dopaminergic deficit. We examine here the evidence for and against an association between ET and PD, and critically review data supporting the notion that a subset of ET patients is predisposed to developing PD.