MeV electron acceleration at 1 kHz with <10 mJ laser pulses: erratum.

In this erratum the funding section of Opt. Lett.42, 215 (2017)OPLEDP0146-959210.1364/OL.42.000215 has been updated.

Measurement of the equation of state of solid-density copper heated with laser-accelerated protons.

We present equation of state (EOS) measurements of solid-density copper heated to 5-10 eV. A copper sample was heated isochorically by hydrogen ions accelerated from an adjacent foil by a high intensity pulsed laser, and probed optically. The measured temperature and expansion are compared against simulations using the most up-to-date wide range EOS tables available.

MeV electron acceleration at 1 kHz with <10 mJ laser pulses.

We demonstrate laser-driven acceleration of electrons to MeV-scale energies at 1 kHz repetition rate using <10 mJ pulses focused on near-critical density He and H2 gas jets. Using the H2 gas jet, electron acceleration to ∼0.5 MeV in ∼10 fC bunches was observed with laser pulse energy as low as 1.3 mJ. Increasing the pulse energy to 10 mJ, we measure ∼1 pC charge bunches with >1 MeV energy for both He and H2 gas jets.

Overall Survival and Response to Systemic Therapy in Metastatic Extrauterine Leiomyosarcoma.

Background. Leiomyosarcomas (LMS) represent a heterogeneous subset of soft tissue sarcomas. Factors influencing prognosis for patients with metastatic extrauterine LMS (euLMS) are not well described. Limited data are available regarding responses to systemic therapy. Methods. We collected clinical and pathologic information for all patients with metastatic euLMS seen at Memorial Sloan Kettering Cancer Center between 1989 and 2012. Objective responses to first-line therapy were analyzed for a subset of patients with available baseline and on-treatment imaging using RECIST 1.1. Results. 215 patients with metastatic euLMS had a median overall survival (OS) of 2.6 years from the time of metastasis. Older age, male sex, and ≥3 initial sites of metastasis were associated with worse OS on multivariate analysis. Objective response rate (ORR) in N = 113 was 19% overall and 25%, 26%, and 25% for gemcitabine, gemcitabine plus docetaxel, and anthracycline-alkylator combinations. Patients whose tumors objectively responded to first-line therapy had a lower risk of death versus those who did not (Hazard Ratio 0.46; 95% CI: 0.26-0.79, p = 0.005). Conclusions. Anthracycline- and gemcitabine-based regimens have similar activity in this cohort of euLMS. Prognostic factors for OS include older age, male sex, and ≥3 initial sites.

Autologous transplant remains the preferred therapy for relapsed APL in CR2.

Despite their favorable prognosis, 10-20% of acute promyelocytic leukemia (APL) patients relapse. Reinduction therapy is often followed by autologous hematopoietic cell transplantation (auto-HCT). Arsenic trioxide (ATO) has become part of standard reinduction and is often followed by auto-HCT. Data on patients in CR2 were collected from two large transplant registries (Center for International Blood and Marrow Transplant Research (CIBMTR) and European Group for Blood and Marrow Transplant (EBMT)) and two specialty referral centers. The outcome of patients in CR2 who received only ATO-based therapy as reinduction was retrospectively compared with those who got an auto-HCT, with or without ATO. Prognostic factors included age, disease risk, extramedullary disease and duration of CR1. Of 207 evaluable patients, the median age was 31.5 years, 15.3% had extramedullary disease and median WBC at diagnosis was 4.8 × 10(9)/L. Sixty-seven patients received ATO alone and 140 underwent auto-HCT. The groups were comparable for age, gender, extramedullary disease, risk group and duration of CR1. At 5 years, overall survival (OS) was 42% and 78% for the ATO-only and auto-HCT groups, respectively (P<0.001). In addition, OS was associated with longer duration of CR1 (P=0.002), but not with disease risk at diagnosis. These data suggest that auto-HCT for APL patients in CR2 results in better OS than ATO-based therapy alone.

[Percutaneous screw fixation of non- or minimally displaced scaphoid fractures]. / Perkutane kanülierte Verschraubung nicht- oder minimal-dislozierter Skaphoidfrakturen.

OBJECTIVE: Providing stability and reduction of the period of immobilisation of non- or minimally displaced scaphoid fractures using a minimally invasive technique. INDICATIONS: Scaphoid fractures of the types A2, B1 and B2 (Herbert's classification) with no or minimal displacement, along with a patient's request for early functional treatment. CONTRAINDICATIONS: Relative contraindications: significant dislocation of the fracture, scaphoid cyst or a too proximal fracture, concomitant fractures of the wrist. Absolute contraindications: pseudoarthrosis, luxation fractures. SURGICAL TECHNIQUE: Minimally invasive percutaneous screw fixation using a double threaded screw. POSTOPERATIVE MANAGEMENT: Postoperative immobilisation in a plaster cast with a thumb inlay for 1-3 weeks until swelling and pain subside. Followed by active physiotherapeutic exercise, however no pressure on the hand for 6 weeks after surgery. RESULTS: Seventy patients with a non- or a minimally displaced scaphoid fracture were treated between 2005 and 2011. We used percutaneous screw fixation as the therapy technique. A total of 57 patients (81%) presented for follow-up. Four patients (5.7%) had an unhealed fracture 6 months postsurgery confirmed. One patient needed revision surgery because of a screw that was too long. None of the patients had a postsurgical infection, haematoma or a complex regional pain syndrome. Smoking and putting pressure on the hand too early have been identified as possible risk factors for the unhealed fractures.

Long-term outcomes following microwave ablation for liver malignancies.

BACKGROUND: Microwave ablation has emerged as a promising treatment for liver malignancies, but there are scant long-term follow-up data. This study evaluated long-term outcomes, with a comparison of 915-MHz and 2.4-GHz ablation systems. METHODS: This was a retrospective review of patients with malignant liver tumours undergoing operative microwave ablation with or without liver resection between 2008 and 2013. Regional or systemic (neo)adjuvant therapy was given selectively. Local recurrence was analysed using competing-risk methods with clustering, and overall survival was determined from Kaplan-Meier curves. RESULTS: A total of 176 patients with 416 tumours were analysed. Colorectal liver metastases (CRLM) comprised 81.0 per cent of tumours, hepatocellular carcinoma 8.4 per cent, primary biliary cancer 1.7 per cent and non-CRLM 8.9 per cent. Median follow-up was 20.5 months. Local recurrence developed after treatment of 33 tumours (7.9 per cent) in 31 patients (17.6 per cent). Recurrence rates increased with tumour size, and were 1.0, 9.3 and 33 per cent for lesions smaller than 1 cm, 1-3 cm and larger than 3 cm respectively. On univariable analysis, the local recurrence rate was higher after ablation of larger tumours (hazard ratio (HR) 2.05 per cm; P < 0.001), in those with a perivascular (HR 3.71; P = 0.001) or subcapsular (HR 2.71; P = 0.008) location, or biliary or non-CRLM histology (HR 2.47; P = 0.036), and with use of the 2.4-GHz ablation system (HR 3.79; P = 0.001). Tumour size (P < 0.001) and perivascular position (P = 0.045) remained significant independent predictors on multivariable analysis. Regional chemotherapy was associated with decreased local recurrence (HR 0.49; P = 0.049). Overall survival at 4 years was 58.3 per cent for CRLM and 79.4 per cent for other pathology (P = 0.360). CONCLUSION: Microwave ablation of liver malignancies, either combined or not combined with liver resection, and selective regional and systemic therapy resulted in good long-term survival. Local recurrence rates were low after treatment of tumours smaller than 3 cm in diameter, and those remote from vessels.

Ultrashort pulsed neutron source.

We report on a novel compact laser-driven neutron source with an unprecedented short pulse duration (<50 ps) and high peak flux (>10(18) n/cm(2)/s), an order of magnitude higher than any existing source. In our experiments, high-energy electron jets are generated from thin (<3 µm) plastic targets irradiated by a petawatt laser. These intense electron beams are employed to generate neutrons from a metal converter. Our method opens venues for enhancing neutron radiography contrast and for creating astrophysical conditions of heavy element synthesis in the laboratory.

High-risk features in radiation-associated breast angiosarcomas.

BACKGROUND: Radiation-associated breast angiosarcoma (RT-AS) is an uncommon malignancy with an incidence of less than 1 % of all soft tissue sarcomas. The overall prognosis is quite dismal with high rates of recurrences and poor overall survival. There is an obvious paucity of data regarding clinical outcomes of patients with breast RT-AS. METHODS: We identified all patients with RT-AS treated at the Memorial Sloan-Kettering Cancer Center between 1982-2011 and collected their correlative clinical information. RESULTS: We identified 79 women with RT-AS with a median age of 68 (range 36-87). The median interval between radiation and development of RT-AS was 7 years (range 3-19). The median time to local and distant recurrence was 1.29 years (95 % CI 0.72-NA) and 2.48 years (95 % CI 1.29-NA), respectively. The median disease-specific survival was 2.97 years (95 % CI 2.21-NA). Independent predictors of worse disease-specific survival included age 68 years (HR 3.11, 95 % CI 1.20-8.08, P=0.020) and deep tumors (HR 3.23, 95 % CI 1.02-10.21, P=0.046.) CONCLUSION: RT-AS has high local/distant recurrence rates, limited duration on standard chemotherapy and poor disease-specific survival.

Prognostic aspects of DCE-MRI in recurrent rectal cancer.

OBJECTIVE: To explore whether pre-reoperative dynamic contrast-enhanced (DCE)-MRI findings correlate with clinical outcome in patients who undergo surgical treatment for recurrent rectal carcinoma. METHODS: A retrospective study of DCE-MRI in patients with recurrent rectal cancer was performed after obtaining an IRB waiver. We queried our PACS from 1998 to 2012 for examinations performed for recurrent disease. Two radiologists in consensus outlined tumour regions of interest on perfusion images. We explored the correlation between K(trans), Kep, Ve, AUC90 and AUC180 with time to re-recurrence of tumour, overall survival and resection margin status. Univariate Cox PH models were used for survival, while univariate logistic regression was used for margin status. RESULTS: Among 58 patients with pre-treatment DCE-MRI who underwent resection, 36 went directly to surgery and 18 had positive margins. K(trans) (0.55, P = 0.012) and Kep (0.93, P = 0.04) were inversely correlated with positive margins. No significant correlations were noted between K(trans), Kep, Ve, AUC90 and AUC180 and overall survival or time to re-recurrence of tumour. CONCLUSION: K(trans) and Kep were significantly associated with clear resection margins; however overall survival and time to re-recurrence were not predicted. Such information might be helpful for treatment individualisation and deserves further investigation.

Dynamic contrast enhanced-MRI for the detection of pathological complete response to neoadjuvant chemotherapy for locally advanced rectal cancer.

OBJECTIVE: To determine the ability of dynamic contrast enhanced (DCE-MRI) to predict pathological complete response (pCR) after preoperative chemotherapy for rectal cancer. METHODS: In a prospective clinical trial, 23/34 enrolled patients underwent pre- and post-treatment DCE-MRI performed at 1.5T. Gadolinium 0.1 mmol/kg was injected at a rate of 2 mL/s. Using a two-compartmental model of vascular space and extravascular extracellular space, K(trans), k(ep), v(e), AUC90, and AUC180 were calculated. Surgical specimens were the gold standard. Baseline, post-treatment and changes in these quantities were compared with clinico-pathological outcomes. For quantitative variable comparison, Spearman's Rank correlation was used. For categorical variable comparison, the Kruskal-Wallis test was used. P ≤ 0.05 was considered significant. RESULTS: Percentage of histological tumour response ranged from 10 to 100%. Six patients showed pCR. Post chemotherapy K(trans) (mean 0.5 min(-1) vs. 0.2 min(-1), P = 0.04) differed significantly between non-pCR and pCR outcomes, respectively and also correlated with percent tumour response and pathological size. Post-treatment residual abnormal soft tissue noted in some cases of pCR prevented an MR impression of complete response based on morphology alone. CONCLUSION: After neoadjuvant chemotherapy in rectal cancer, MR perfusional characteristics have been identified that can aid in the distinction between incomplete response and pCR. KEY POINTS: Dynamic contrast enhanced (DCE) MRI provides perfusion characteristics of tumours. These objective quantitative measures may be more helpful than subjective imaging alone Some parameters differed markedly between completely responding and incompletely responding rectal cancers. Thus DCE-MRI can potentially offer treatment-altering imaging biomarkers.