A phase II trial of oxaliplatin in patients with advanced melanoma

18016

Background: Oxaliplatin is a platinum derivative without nephrotoxicity with in vitro activity against human melanoma cell lines. (Mohammed, MQ, 2000; Tashiro, T, 1989). A Phase I trial suggested activity in melanoma (Mathe, G, 1986) but Phase II data is lacking. A non-nephrotoxic platinum compound active in melanoma is of interest in the development of combination chemo-or chemoimmunotherapy. Methods: This was a Phase II prospective study of oxaliplatin in patients with previously treated or refractory advanced melanoma. The primary endpoint was to evaluate the response rate, survival, freedom from progression (FFP) and the tolerability of oxaliplatin in this patient population. Key inclusion criteria were: metastatic (stage IV) or unresectable malignant melanoma progressing following treatment with at least one and at most three chemotherapy regimens. ECOG PS 0–2, measurable disease and adequate organ and marrow function were required. Oxaliplatin 130 mg/m2 was given IV in 250–500 mL D5W over 120 minutes every 21 days for at least 2 cycles. Patients were evaluated for response every 2 cycles. Gehan’s two-stage design was utilized. Results: Ten patients were treated between March 2004 and March 2005. Three patients were female and 3 male with a median age of 62.5 years. All patients had PS 0–1. The median number of cycles was 2 (1–6). Three patients had disease stabilization (SD) for median of 3 months. No objective responses were seen; therefore, the study did not progress to the second stage.All patients have progressed and all have expired but one. Median survival from registration was 168 days (128–383). Toxicities included grade 2 fatigue (2 pts) and grade 2 neuropathy (3 pts); one patient had grade 3 diarrhea. Conclusions: Treatment with oxaliplatin in previously treated patients with melanoma is well tolerated at the dose and schedule studied but did not result in objective responses and further development in this population cannot be recommended. Incorporation into combination regimens in previously untreated patients may be of interest.

No significant financial relationships to disclose.

Phase II trial of oxaliplatin and gemcitabine with bevacizumab in first-line advanced non-small cell lung cancer (NSCLC)

17009

Background: Oxaliplatin-Gemcitabine (GemOx) is an active and well tolerated. Bevacizumab (BV) prolongs survival when combined with carboplatin-paclitaxel. This phase II trial evaluates the efficacy of GemOx + BV as 1st line therapy for advanced NSCLC patients. Methods: Pts with stage IIIB (effusion) and IV non-squamous NSCLC, ECOG PS 0 or 1, no CNS metastasis, and no other contraindications to BV, are eligible. Prior therapy for earlier-stage disease allowed if completed at least 12 months before enrollment. Treatment consists of Gem 1000 mg/m2 on d1 and 8, Ox 130 mg/m2 on d1, and BV 15 mg/kg on d1, repeated every 3 wks for a total 4 cycles. Pts who respond or have stable disease receive BV maintenance until progression. Main endpoints are response rate (RR), grade (Gr) 3–4 toxicities, time to progression (TTP), and overall survival (OS). Results: As of 12/05, 26 out of 50 projected pts have been enrolled from 4 institutions. M/F 17/9; median age 65y (45,81); IIIB/IV 3/23; PS 0/1 8/18. Median F/U time is 3.7 months. 24 pts are evaluable for toxicity: 1Gr3 ANC; 1Gr3 and 4 PLT; no FN.3 Gr3 diarrhea and 2 Gr3 N/V; 1Gr3 and 4 hypophosphatemia; 1 pt had ischemic bowel after the 1st cycle, recovered fully and was removed from study; 1 pt died of liver failure in the 1st cycle. No bleeding complications have occurred. 22 pts are evaluable for RR (ITT): 7 PR (31%); 8 SD (36%). TTP and OS data not yet available. Conclusions: This is the first report of GemOx in combination with BV in advanced NSCLC. This regimen has minimal hematologic toxicity but selected non-hematologic toxicities are noted. Activity appears promising and merits further investigation. Accrual is ongoing.

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Placing the boost in breast-conservation radiotherapy: A review of the role, indications and techniques for breast-boost radiotherapy

Randomised trials have established that the addition of a boost dose of radiotherapy to the lumpectomy site after whole-breast adjuvant radiotherapy further improves local control achieved by whole-breast radiotherapy alone. The absolute size of this benefit varies according to the baseline risk of local recurrence. Age is the strongest predictor of benefit. Below the age of 40 years, the absolute benefit of a boost seems to be substantial, and there are no clearly identified groups unlikely to benefit. Above the age of 50 years, the benefit is small, and several additional risk factors for local failure would need to be present to merit boost treatment. These may include tumour size, high grade, high mitotic rate, lymphovascular invasion, extensive and high grade associated with intraduct carcinoma, receptor-positive tumours when avoidance of anti-oestrogen therapy is desired or receptor-negative tumours. Other independent reasonable indications for the use of a boost would be positive margins where further surgery is not indicated. If a boost is indicated, a variety of techniques may be used and toxicity and cosmetic results remain highly acceptable. Overall, there seems to be no substantial differences in boost technique results; however, interstitial techniques may have advantages for deeper targets compared with electrons. Irrespective of technique, accurate localisation will maximise the benefit of a boost. Surgical clips are strongly recommended to facilitate localisation.

Priming of visual route memories

Ants travelling to and fro between their nest and a foraging area may follow stereotyped foodward and homeward routes that are guided by different visual and directional memory sequences. Honeybees are known to fly a feeder-to-hive or hive-to-feeder vector according to whether or not they have recently fed--their feeding state controls which compass direction they select. We show here that the feeding state of the wood ant Formica rufa also determines the choice between an outward or inward journey, but by priming the selective retrieval of visual landmark memories.

Rewarming of healthy volunteers after induced mild hypothermia: a healthy volunteer study

OBJECTIVES

The study compares the efficacy of two active and one passive warming interventions in healthy volunteers with induced mild hypothermia.

METHODS

Eight volunteers were studied in a random order crossover design. Each volunteer was studied during re-warming from a core temperature of 35 degrees C with each of: a radiant warmer (Fisher & Paykel); a forced air warmer (Augustine Medical), and a polyester filled blanket, to re-warm.

RESULTS

No significant differences in re-warming rates were observed between the three warming devices. It was found that the subject's endogenous heat production was the major contributor to the re-warming of these volunteers. Metabolic rates of over 350 W were seen during the study.

CONCLUSIONS

For patients with mild hypothermia and in whom shivering is not contraindicated our data would indicate that the rate of re-warming would be little different whether a blanket or one of the two active devices were used. In the field, this may provide the caregiver a useful choice.

Vitamin C supplementation in very preterm infants: a randomised controlled trial

OBJECTIVE

To determine whether regulating vitamin C (ascorbic acid: AA) intake to achieve higher or lower plasma concentrations was associated with improved clinical outcome.

DESIGN

A double blind, randomised controlled trial.

SETTING

Neonatal intensive care unit at Christchurch Women's Hospital.

PATIENTS

Infants with birth weight <1500 g or gestation <32 weeks, admitted to the unit within 48 hours of birth.

INTERVENTION

Infants were randomised to one of three protocols with regard to AA supplementation for the first 28 days of life: group LL received low supplementation throughout; group LH received low until day 10 and then high: group HH received high throughout.

MAIN OUTCOME MEASURES

Primary outcome measures were oxygen requirement at 28 days and 36 weeks postmenstrual age, total days supplemental oxygen, and retinopathy of prematurity. AA concentrations were measured at study entry (day 2), and days 10, 21, and 28.

RESULTS

A total of 119 infants were enrolled over 24 months (mean gestation 28.4 weeks; birth weight 1161 g). Six infants died, and these had significantly higher AA concentrations before randomisation than surviving infants (116 micromol/l (95% confidence interval 90 to 142) v 51 micromol/l (45 to 58), p<0.0001). There were no significant differences in primary outcomes between the groups. However, the proportion of surviving infants with an oxygen requirement at 36 weeks postmenstrual age in group HH (19%) was half that in group LL (41%) (p=0.06).

CONCLUSIONS

In a randomised controlled trial, no significant benefits or harmful effects were associated with treatment allocation to higher or lower AA supplementation throughout the first 28 days of life.

Absence of adverse early quality of life outcomes of radiation therapy in breast conservation therapy for early breast cancer

The New South Wales Breast Radiation Oncology Group has completed a prospective multicentre study of the impact of radiation therapy (RT) on acute toxicity and quality of life (QoL) in women with early breast cancer treated with breast conservation therapy. The patient group received adjuvant breast tangential RT after wide local excision of breast cancer. Acute toxicity and cosmesis was assessed quantitatively and qualitatively. European Organization of Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-30) and Perceived Adjustment to Chronic Illness Scale (PACIS) were the QoL instruments used. Of 175 women, 34.3% described lethargy leading to a significant disruption to normal activity during RT. At week 6, this had reduced to 7.5% reporting significant lethargy. No negative effects on QoL were noted over the time period of RT; EORTC demonstrated no difference (P = 0.79). PACIS recorded a significant improvement in functioning (P < 0.001) from baseline to week 6. Univariate analysis on potential predictive patient, tumour and treatment factors demonstrated an association of baseline pre-RT breast discomfort with worse lethargy (P = 0.03), EORTC (P < 0.01) and PACIS (P < 0.01) measures. This study confirms the minimal impact of RT on patient functioning at 6 weeks post-treatment.

Animal navigation: path integration, visual landmarks and cognitive maps

Animals typically have several navigational strategies available to them. Interactions between these strategies can reduce navigational errors and may lead to the emergence of new capacities.

Switching destinations: memory change in wood ants

We have studied the changing use of spatial memories in wood ants by charting how the ants' paths transform when ants are first trained to feed at one site and must then switch to another site. Because ants, which are trained to approach a single feeding site from a single starting point, are attracted directly to that goal when started from unfamiliar positions, we describe the ants' paths in terms of the use of two stored snapshots. Each snapshot consists of retinotopic views of the ants' surroundings acquired at one of the two feeding sites. When a snapshot is activated, it draws an ant to the related site from a wide range of directions. Here, we focus on routes that occur before ants have learnt to go directly from the start to the second site. The initial direction of the ant's path is then mostly aimed either at the first site or between the two sites. On 62.2% of all recorded paths, this segment is followed by an abrupt turn, after which the ant often aims directly at the second feeding site. The details of this behaviour suggest that, after the turn, control of the path switches from the snapshot recorded at the first feeding site (or some combination of the two snapshots) to the snapshot recorded at the second feeding site. We discuss different ways in which control might be transferred from one snapshot to the other.

Route learning by insects

Ants and other insects often follow fixed routes from their nest to a foraging site. The shape of an ant's route is set, initially, by navigational strategies, such as path integration and the ant's innate responses to landmarks, which depend minimally on memory. With increasing experience, these early routes are stabilised through the learning of views of landmarks and of associated actions. The substitution of memory-based strategies makes an insect's route more robust and precise. The ability to select between different learnt routes might incur additional memory requirements to those needed for performing a route, and lead to the associative grouping of those memories that relate to a particular route.

The binding and recall of snapshot memories in wood ants (Formica rufa L.)

Insects can locate spatial goals by means of 2-D retinotopic views of the surrounding landmarks, which they memorise from the vantage point of the goal. Wood ants acquire such snapshot memories while fixating conspicuous landmarks with frontal retina, and their snapshots extend horizontally at least 120°into the periphery. Are spatially separate items within such an extended snapshot bound together so that a snapshot is recalled as a whole, or are its components recognised individually?

We approached this question by training ants to find food midway between two upright black cylinders of different sizes and then examined where they searched when they were given two cylinders of the same size. If the ants know which cylinder replaces the small cylinder and which the large, they should search at a position where the two equal-sized cylinders subtend the same angles as do the training cylinders when viewed from the feeder. Ants conformed to this prediction under one condition, searching at a shorter distance from the substitute for the large cylinder than from the substitute for the small cylinder. But, under another condition, ants were unable to distinguish between the two equal-sized cylinders. Ants failed when white curtains completely surrounded the platform on which the cylinders were placed. They succeeded when one side of the platform had a patterned curtain.

We suggest that ants take two snapshots at the feeding site, one when facing the small cylinder and one when facing the large cylinder, and that each snapshot includes the patterned curtain, if it is there. Ants will view the patterned curtain with the lateral retina of one eye when facing the small cylinder and with the lateral retina of the other eye when facing the large cylinder. Our data suggest that there may be associative links between these spatially separate components of the snapshot, which cause the memory of the small cylinder or the large cylinder to be recalled according to which eye sees the curtain. It seems that an extended snapshot not only enhances the accuracy of localisation but can also increase the reliability of snapshot recall, provided that the components of a snapshot are bound together.

Impact of phosphorus application and sheep grazing on the botanical composition of sown pasture and naturalised, native grass pasture

Botanical composition (basal cover) was measured in 4 replicated pasture treatments based on Phalaris aquatica and Trifolium subterraneum at Hall, ACT (unfertilised with low and high stocking rate; fertilised with low and high stocking rate) and in 2 unreplicated pasture treatments based on native perennial grasses (Austrodanthonia spp. and Microlaena stipoides) and T. subterraneum at Bookham, NSW (unfertilised and low stocking rate; fertilised and high stocking rate). Current economic pressures are encouraging graziers to increase their use of phosphorus (P) fertiliser and to adopt higher stocking rates. The objective of the research was to determine the changes in botanical composition that may result from these changes in grazing systems management. At Hall, annual species differed in their responses to P fertility. Notably, basal cover of Bromus spp. increased significantly with P application, whereas Vulpia spp. decreased significantly. Basal cover of T. subterraneum also increased significantly with P application when stocking rate was high, but was reduced by P application if stocking rate was low. Basal cover of perennial grasses (P. aquatica and Holcus lanatus) was significantly higher at low stocking rate when P was applied. The botanical composition of high stocking rate treatments was relatively stable over time, which contrasted with less stable composition at low stocking rate. At Bookham, fertilised pasture in unreplicated paddocks appeared to have a higher basal cover of productive annual species (i.e. Bromus spp. and T. subterraneum), but native perennial grasses appeared to have lower basal cover in comparison with the unfertilised area. These results indicated that in some cases, the influence of P fertiliser and high stocking rates on botanical composition was favourable (i.e. increased basal cover of P. aquatica and T. subterraneum) and in others it could be detrimental (i.e. lower basal cover of native perennial grasses).

Snapshot Memories and Landmark Guidance in Wood Ants

Insects are thought to pinpoint a place by using memorized "snapshots," i.e., two-dimensional retinotopic views of the surrounding landmarks recorded when at the place (reviewed in ). Insects then reach the place by moving until their current view matches their snapshot. To determine when snapshots are recalled, and how differences between view and snapshot are translated into appropriate movements, we analyzed the approaches of wood ants to a feeding site that was located in the center of an array of two or three cylinders. In ants, contrary to flying hymenopterans, body orientation and direction of travel are collinear, so that an ant approaching an object always looks at it with frontal visual field. On their way to a food site, ants fixated and approached a cylinder predominantly when its angular size was smaller than when viewed from the food site. This finding implies that ants store snapshots at this place while fixating landmarks with frontal retina, so simplifying the later alignment of snapshots with their current view. It also means that ants recall snapshots well in advance of reaching the place. Although snapshots are centered on a landmark, we show that they extend at least 120 degrees into the periphery.

An in vitro Flaviviridae replicase system capable of authentic RNA replication

We have established an in vitro replication system for bovine viral diarrhea virus (BVDV), a surrogate for the closely-related hepatitis C virus. In an in vitro reaction, BVDV replication complexes synthesize vRNA and replicative form (RF) and replicative intermediate (RI) RNAs. Kinetic and heparin trapping experiments demonstrate the recycling of RF and RI products and the initiation of vRNA synthesis in this system. Consistent with this, quantitative hybridization reveals the asymmetric synthesis of positive and negative strand RNA products. These findings support the notion that RF serves as a template and RI as a precursor in the synthesis of vRNA. Furthermore, the antiviral activity of an NS5B inhibitor was similar in BVDV replicase and infectivity assays. Together, these results indicate that the in vitro activity of BVDV replicase complexes recapitulates RNA replication that occurs in infected cells, providing a system in which to study both mechanisms and inhibitors of Flaviviridae replication.

Why a breast boost should remain a controversial aspect of routine breast conservation management in Australia and New Zealand in 2002

Two randomized trials have recently shown a statistically significant improvement in local control when a boost is employed in the conservative treatment of early breast cancer. However, unresolved issues of cost effectiveness, potentially increased toxicity and the inability to automatically generalize these results to Australian and New Zealand practice remain. In view of these unresolved controversies, the St George and Wollongong hospitals breast boost trial (SGW trial) will continue to recruit.

The influence of beacon-aiming on the routes of wood ants

Many insects have an innate propensity to approach conspicuous objects. We explore how such beacon aiming determines the shape of a wood ant's habitual route. We find that a single large black cylinder within an arena biases the route taken by ants as they run from a start position at one end of the arena to reach a feeder at the other. Ants learn a stable route with the first segment of their trajectory aimed at the cylinder, which becomes an intermediate goal on the way to the feeder. When in occasional tests the cylinder is removed or displaced, ants head for the usual site of the cylinder. They also aim for the same site when the cylinder is removed and the ant's normal start position is changed. This behaviour suggests that visual features of the arena are learnt from the vantage point of the cylinder and that this stored snapshot guides the ant to that site. Ants thus reinforce their ability to reach the cylinder by learning other visual features in their surroundings that can also steer them to its location. The use of beacon aiming in fixing routes has several benefits. Because the same path will be traversed on every trial, beacon aiming facilitates the acquisition of routes. Beacon aiming also increases the robustness of learnt routes: ants straying from the route will be attracted to the closest beacon and so regain their habitual paths.

View-based navigation in insects: how wood ants (Formica rufaL.) look at and are guided by extended landmarks

Bees, wasps and ants learn landmarks as views from particular vantage points, storing the retinal positions of landmark edges. By moving so as to minimise the difference between their stored and current view, they can return to the vantage point from which a view was taken. We have examined what wood ants learn about a laterally placed, extended landmark, a wall, while walking parallel to it to reach a feeder and how they use this stored information to guide their path. Manipulation of the height of the wall and the ant's starting distance from it reveals that ants maintain a desired distance from the wall by keeping the image of the top of the wall at a particular retinal elevation. Ants can thus employ image matching both for returning to a place and for following a fixed route.

Unlike many flying insects, an ant's direction of motion while walking is always along its longitudinal body axis and, perhaps for this reason, it favours its frontal retina for viewing discrete landmarks. We find that ants also use their frontal retina for viewing a laterally placed wall. On a coarse scale, the ant's path along the wall is straight, but on a finer scale it is roughly sinusoidal, allowing the ant to scan the surrounding landscape with its frontal retina. The ant's side-to-side scanning means that the wall is viewed with its frontal retina for phases of the scanning cycle throughout its trajectory. Details of the scanning pattern depend on the scene. Ants scan further to the side that is empty of the wall than to the side containing the wall, and they scan further into the wall side when the wall is of a lower apparent height. We conclude that frontal retina is employed for image storage and for path control.