Observation of ultrahigh-energy cosmic rays with the ANITA balloon-borne radio interferometer

We report the observation of 16 cosmic ray events with a mean energy of 1.5 × 10¹⁹ eV via radio pulses originating from the interaction of the cosmic ray air shower with the Antarctic geomagnetic field, a process known as geosynchrotron emission. We present measurements in the 300-900 MHz range, which are the first self-triggered, first ultrawide band, first far-field, and the highest energy sample of cosmic ray events collected with the radio technique. Their properties are inconsistent with current ground-based geosynchrotron models. The emission is 100% polarized in the plane perpendicular to the projected geomagnetic field. Fourteen events are seen to have a phase inversion due to reflection of the radio beam off the ice surface, and two additional events are seen directly from above the horizon. Based on a likelihood analysis, we estimate angular pointing precision of order 2° for the event arrival directions.

Cancer in older people: a tale of two disciplines

Management of cancer in the elderly presents an unprecedented challenge in Australia with the proportion of the population aged over 65 years set to double over the next four decades. Despite the complex healthcare needs of the older patient with cancer, there is currently little communication or cooperation between the fields of oncology and geriatrics. Improved interdisciplinary communication would facilitate care that is framed within current oncology practice while taking account of physiological age, complex comorbidities, risk of adverse events and pharmacological interactions as well as the implications of cognitive impairment on suitability for treatment and consent. An important first step has been taken towards the development of a strategic, focused and collaborative approach to the management of cancer in older people through a national interdisciplinary workshop convened by the Clinical Oncological Society of Australia in April 2008. Engagement and commitment of both oncology and geriatric disciplines is now critical to ensure that momentum is not lost in progressing this important and growing area of healthcare.

Alcohol, signaling, and ECM turnover

Alcohol is recognized as a direct hepatotoxin, but the precise molecular pathways that are important for the initiation and progression of alcohol-induced tissue injury are not completely understood. The current understanding of alcohol toxicity to organs suggests that alcohol initiates injury by generation of oxidative and nonoxidative ethanol metabolites and via translocation of gut-derived endotoxin. These processes lead to cellular injury and stimulation of the inflammatory responses mediated through a variety of molecules. With continuing alcohol abuse, the injury progresses through impairment of tissue regeneration and extracellular matrix (ECM) turnover, leading to fibrogenesis and cirrhosis. Several cell types are involved in this process, the predominant being stellate cells, macrophages, and parenchymal cells. In response to alcohol, growth factors and cytokines activate many signaling cascades that regulate fibrogenesis. This mini-review brings together research focusing on the underlying mechanisms of alcohol-mediated injury in a number of organs. It highlights the various processes and molecules that are likely involved in inflammation, immune modulation, susceptibility to infection, ECM turnover and fibrogenesis in the liver, pancreas, and lung triggered by alcohol abuse.

New limits on the ultrahigh energy cosmic neutrino flux from the ANITA experiment

We report initial results of the first flight of the Antarctic Impulsive Transient Antenna (ANITA-1) 2006-2007 Long Duration Balloon flight, which searched for evidence of a diffuse flux of cosmic neutrinos above energies of E(nu) approximately 3 x 10(18) eV. ANITA-1 flew for 35 days looking for radio impulses due to the Askaryan effect in neutrino-induced electromagnetic showers within the Antarctic ice sheets. We report here on our initial analysis, which was performed as a blind search of the data. No neutrino candidates are seen, with no detected physics background. We set model-independent limits based on this result. Upper limits derived from our analysis rule out the highest cosmogenic neutrino models. In a background horizontal-polarization channel, we also detect six events consistent with radio impulses from ultrahigh energy extensive air showers.

ESPAC-3(v2): A multicenter, international, open-label, randomized, controlled phase III trial of adjuvant 5-fluorouracil/folinic acid (5-FU/FA) versus gemcitabine (GEM) in patients with resected pancreatic ductal adenocarcinoma

LBA4505

Background: Adjuvant 5-FU/FA (ESPAC-1 trial) and GEM (CONKO-001 trial) provide improved survival for patients with resected pancreatic cancer compared to no chemotherapy. The aim of the ESPAC-3 (v2) trial was to compare 5FU/FA vs GEM to identify if either adjuvant chemotherapy was associated with a significantly better survival. Methods: Patients with an R0/R1 resection for pancreatic ductal adenocarcinoma were randomized (stratified for resection margin status and country) <8 weeks of surgery to receive either 5FU/FA (FA, 20 mg/m2, iv bolus injection followed by 5-FU, 425 mg/m2, iv bolus injection given 1–5d every 28 days) or GEM (1,000mg/m2 iv infusion 1d, 8d and 15d every 4 weeks) for 6 months. The primary outcome measure was overall survival; the secondary measures were toxicity, progression free survival and quality of life. 1,030 patients were needed to detect a 10% difference in 2-year survival rates with 90% power. Results: 1,088 patients from 16 countries were randomized from July 2000 to Jan 2007 (5FU/FA = 551, GEM = 537). Median (range) age was 63 (31–85) years; 598 (55%) were men. Median tumor size was 30 (20–350) mm; 384 (35%) were R1 resections; 777 (72%) were node positive; and 263 (25%) were poorly differentiated tumors. Final analysis was carried out on an intention to treat basis with a minimum of 2 years follow-up after 753 (69%) patients had died. Median (IQR) follow-up of 335 alive patients was 34.2 (27.1–43.4) months, equal across treatment groups. Median survival from resection of patients treated with 5FU/FA was 23.0 (95% CI: 21.1, 25.0) months and for patients treated with GEM this was 23.6 (95%CI: 21.4, 26.4) months. Log-rank analysis revealed no statistically significant difference in survival estimates between the treatment groups (c2LR=0.7, p=0.39, HRGEM=0.94 (95%CI: 0.81, 1.08)). There was no significant difference in the effect of treatment across subgroups according to R status (test of heterogeneity c21=0.3, p=0.56). Conclusions: This is the largest adjuvant trial ever conducted for pancreatic ductal adenocarcinoma and showed no significant difference in survival between adjuvant 5FU/FA and adjuvant GEM.

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Phase II trial of nab-paclitaxel as first-line therapy of hormone refractory metastatic prostate cancer (HRPC)

5152

Background: Many patients with hormone refractory prostate cancer have poor tolerance to treatment. Docetaxel chemotherapy was shown to improve survival but has substantial toxicity, requires steroid administration, may cause poorly reversible neuropathy and requires long infusion times, all limiting its use. Nab-paclitaxel, an albumin-bound nanopaticle form of paclitaxel, delivers paclitaxel without steroids, requires only 30 minutes infusion time and has favorable toxicity profile that may be more tolerable but effective in patients with prostate cancer. The goal of this study was to evaluate the efficacy and toxicity of nab-paclitaxel in first line chemotherapy of men with castration resistant prostate cancer. Methods: nab-paclitaxel was given iv100 mg/m2 weekly x 3 of 4 weeks cycles. Main eligibility criteria include: hormone refractory metastatic prostate cancer, no prior chemotherapy, performance status 0–2. Primary endpoint was efficacy based on prostate-specific antigen (PSA) response. PSA response was PSA decrease of >50%, progressive disease (PD) was PSA increase of >25%, stable disease (SD) was <25% PSA increase or <50% decrease sustained longer that 8 weeks. Results: There are 38 patients enrolled, 35 were evaluable for response. Median age was 71 years old (range 57–86). One patient discontinued the treatment after 1 infusion due to toxicity (elevated ALT). PSA response was seen in 9 (25%) patients and SD in 15 patients (43%), with an overall response rate of 25% and clinical benefit of 68%. Seven patients received treatment for ≥ 6 months with minimal toxicity (range 6–10 months). Grade 3 related hematologic toxicity was reported in 7 (18%) patients (4 anemia, 4 neutropenia), grade 3 related non-hematologic toxicity was reported in 6 patients (1 hypokalemia, 1 muscle weakness, 2 fatigue, 1 fever, 1 neuropathy, 1 ALT elevation). Conclusions: Nab-paclitaxel has activity in patients with metastatic hormone refractory prostate cancer. This regimen was well tolerated, and may be useful in patients who are not suitable candidates for docetaxel based therapy.

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GOFURTGO trial (GFG): An AGITG multicenter phase II study of fixed dose rate gemcitabine-oxaliplatin (Gem-Ox) integrated with concomitant 5FU and 3-D conformal radiotherapy (5FU-3DRT) for the treatment of locally advanced pancreatic cancer (LAPC)

4616

Background: Our previous study of Gem with sandwich 5FU-3DRT for LAPC was encouraging (Br J Cancer 2007: 97, 464–471). Gem-Ox has higher response rate than Gem, improved progression free survival (PFS) but not overall survival (OS). Its use in LAPC may improve local control (LC) and delay systemic spread. GFG is a study of induction (ind) Gem-Ox, then 5FU-3DRT, then consolidation (con) Gem-Ox. Primary outcome is feasibility using proportion of patients (pts) receiving > 80% planned dose for each component. Secondary outcomes are safety, activity and QOL. Methods: Pts with previously untreated inoperable LAPC, M0, measurable disease, ECOG 0–2 were given Gem (1000mg/m2 d1 + d15 q28), Ox (100mg/m2 d2 + d16 q28) in both ind (1 cycle) & con (3 cycles), & 5FU 200mg/m2/d over 6 weeks during RT of 54Gy in 30 fractions of 1.8Gy. Results: 48 pts were enrolled, median age 61y (44–81y), PS 0/1=96%, regional lymph nodes=44%, T4=46%. Worst grade (G) for anaemia (10%); fatigue, nausea (8%); diarrhoea, vomiting, neutropenia, infection (4%); stomatitis, anorexia (2%) was G3. Thrombocytopenia was G3=2% G4=2%; liver function was G3=23% G4=6%; late radiation toxicity was G3=2% G4=2% (both gastric bleeding). Half of all pts completed all planned cycles (24 pts); 29% of pts received >80% of all treatment (14 pts); 70% of pts received >80% of all chemoradiation (33 pts). Pts ceased treatment for toxicity (16%), PD (21%) or doctor/pt preference (4/2%). Global QOL did not significantly change from baseline. Median duration of LC, PFS, OS were 15.8, 9.9, 15.4m at median follow up of 29.7m. Exploratory analysis of age, disease stage, PS, CA19–9 or WCC found no univariate predictors of PFS or treatment completion. 8/48 pts survived >24m. Conclusions: Compared to our previous study using the same radiation schedule, addition of oxaliplatin was associated with improved LC, PFS & OS (prev. 11.9, 7.1 & 11.7m) without significant offset by toxicity. The extended duration of LC and a subset who had a very prolonged benefit may be due to patient selection but equally may suggest an incremental benefit from more intensive systemic therapy requiring further study in controlled trials.

[Table: see text]

ESPAC-3(v2): A multicenter, international, open-label, randomized controlled phase III trial of adjuvant 5-fluorouracil/folinic acid (5-FU/FA) versus gemcitabine (GEM) in patients with resected pancreatic ductal adenocarcinoma

LBA4505

The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology.

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Constipation does not develop following elective hysterectomy: a prospective, controlled study

Although there have been reports that women develop constipation following hysterectomy, previous studies were either retrospective or uncontrolled. The aim of this prospective, controlled study was to assess whether constipation develops after elective hysterectomy. Women undergoing elective gynaecological surgery were compared to matched non-surgery controls at enrollment and 3 and 12 months after surgery. The subset of women who underwent elective hysterectomy was the study group for the present report. Fifty-eight of the 132 elective surgery patients underwent hysterectomy and were compared to 123 controls. There was no difference between the groups at any follow-up point in functional constipation (P = 1.0), frequency of stools (P = 0.92), stool consistency (P = 0.42), straining (P = 0.43), feeling of obstruction (P = 0.6) or need to manually evacuate stool (P = 1.0). Significantly, more hysterectomy patients without baseline pain did develop abdominal pain at 3 or 12 months than non-surgery controls (16.7% vs 3.6%, P = 0.008). We conclude that there was no significant change in bowel habit or stool characteristics in women undergoing hysterectomy even though many developed abdominal pain. This prospective, controlled study challenges existing data regarding the effect of hysterectomy on constipation.