Characteristics and outcome of patients (pts) enrolled on phase I trials: A report from the Pediatric Oncology Branch, NCI

9550

Background: Knowledge of the characteristics and outcomes of pts enrolled on pediatric phase I trials may aid in the design of future phase I trials and selection of pts. Methods: Pre-enrollment characteristics and treatment outcomes (toxicity, response, survival) were retrospectively analyzed from pts with refractory solid tumors enrolled in 16 phase I trials with similar eligibility criteria from 1992 to 2005. The relationship between patient characteristics and dose-limiting toxicity (DLT) was evaluated using multivariate analysis. Results: Of 262 pts (62% M, 38% F) eligible for analysis, 147 were on trials of myelosuppressive drugs (MS) and 115 were enrolled on trials of non-MS. 50 pts (19%) participated in =2 separate trials. Median (range) or (frequency) entry characteristics were: age 13.5 yrs (1–24); ECOG performance score 0 (30%), 1 (50%), 2 (19%); prior regimens 2 (0–9); prior stem cell transplant (20%); prior radiation (66%); concomitant medications 1 (0–12); and presence of metastatic disease (65%). 94% of pts were evaluable for the primary trial outcome, and 92% participated in pharmacokinetic (PK) studies. 17% of pts had grade 3 as their highest-grade toxicity. 22% of pts had grade 4 as their highest-grade toxicity, of which 91% were hematological. DLT rate was 18%. 5% of pts came off study due to toxicity, and treatment related death occurred in 0.3%. Age, prior radiation, medications, prior regimens, performance status, gender, transplant history, and drug dose expressed as a fraction of the maximum tolerated dose were included in the multivariate analysis. Only drug dose (OR 14.2, 95% CI 3.0–67.8) and prior radiation (OR 3.4, 95% CI 1.1–10.7) were statistically significantly associated with increased risk of developing DLT after adjusting for all other variables. The median number of cycles was 1 (range 0–31). Complete and partial response rate was 3%, however, 18% of pts had stable disease (received = 3 cycles). The median survival (Kaplan Meier analysis) from time of enrollment was 5 months. Conclusion: Standard phase I eligibility criteria selected a population of pts who tolerated the investigational agents well and >90% were evaluable for the toxicity and PK endpoints. Prior radiation was associated with a greater risk for DLT.

No significant financial relationships to disclose.

The pharmacokinetics (PK) and pharmacodynamics (PD) of ABT-751 in children with recurrent neuroblastoma or other solid tumors

9557

Background: ABT-751 is an orally administered agent that binds to the colchicine site on β-tubulin and blocks microtubule formation. We studied the PK and PD of ABT-751 and its sulfate and glucuronide conjugates in children enrolled on a phase 1 trial in solid tumors and a pilot study in neuroblastoma. Methods: Seventy-two children (2–18 yrs) received ABT-751 on a once, daily × 7d or daily × 21d schedule. Sixty had PK plasma sampling (53 sets analyzed), and 41 had a 24h urine collection after the first dose. Drug concentrations were quantified with a LC/MS/MS assay. Results: Median (range) plasma PK parameters are shown in the table . ABT-751 was rapidly absorbed (Tmax , 2h), and the Cmax and AUC0-8 increased in proportion to dose. The median molar ratio of the sulfate plasma AUC0-8 to glucuronide plasma AUC0-8 was 1.5. The median (range) percent of the administered dose excreted in urine as ABT-751, glucuronide, or sulfate conjugates was 0.09 (0–0.4)%, 10.2 (1.0–38.5)%, and 12.6 (2.3–50.9)%, respectively. The median ABT-751 AUC0-8 was higher in patients with dose-limiting toxicity (DLT) compared to those without DLT on the 7d (118 vs. 74.5 μg·h/mL; P=0.014) and 21d (73.8 vs 49.3 μg·h/mL; P=0.049) schedules. In 28 patients with neuroblastoma, the AUC0-8 did not correlate with time to progression. Apparent clearance (CL/F) did not correlate with age or gender. Conclusions: PK samples were obtained from 83% (60/72) of children enrolled. The ABT-751 AUC0-8 was dose proportional; inter- and intra-patient variability was low. Patients who experienced DLT had higher ABT-751 AUC0-8. The mean CL/F of ABT-751 was similar to that observed in adults (40 mL/min/m2) but did not correlate with age or gender. The sulfate conjugate was the primary metabolite in plasma and urine. Urinary excretion was not a major route of elimination of the parent drug.

[Table: see text]

No significant financial relationships to disclose.

Radiographic tumor response in pediatric patients with newly diagnosed localized (LOC) or metastatic (MET) Ewing’s sarcoma (EWS) following neoadjuvant chemotherapy

20008

Background: Standard treatment for EWS includes vincristine, doxorubicin, cyclophosphamide (VDC) alternating with ifosfamide and etoposide (IE). Using this therapy, overall survival is 70% in patients with LOC EWS and 30% in patients with MET EWS. We compared the radiographic response to VDC and IE in patients with LOC or MET EWS. Methods: We conducted a randomized trial comparing pegfilgrastim to filgrastim in patients treated with VDC (cycles 1, 2, 5, 9, 11, 13) and IE (cycles 3, 4, 6–8, 10, 12, 14). Local control with radiation or surgery was initiated after cycle 5. We assessed radiographic response after VDC (C1,2) and IE (C3,4) using 1-dimensional (RECIST) and 2-dimensional (WHO) criteria. Measurements were performed using MEDx. Results: Twenty-one patients with EWS, median age 20y (6–25y), were enrolled; 16 were evaluable for this analysis. Primary tumors were in extremity (n=5) or central axis (n=11). Eight patients had MET disease (pulmonary only, n=4). Median (range) decrease in tumor size by WHO after C4 was 61% (40–92%) for LOC and 83% (47–94%) for MET. Decrease by treatment is presented in the table . Overall responses after 4 cycles for LOC patients were 5 PR, 3 SD using RECIST, and 6 PR, 2 SD using WHO. For MET patients, overall responses were the same using RECIST and WHO, 7 PR, and 1SD. Conclusion: Patients with MET EWS responded as well as those with LOC EWS after 4 cycles of neoadjuvant chemotherapy. Similar overall response was demonstrated using RECIST or WHO. Tumor response after VDC was greater than after IE, possibly due to sequence of administration, but patients had continued tumor response with IE.

[Table: see text]

No significant financial relationships to disclose.

Development and evaluation of the electromagnetic hypersensitivity questionnaire

Electromagnetic hypersensitivity (EHS) syndrome is usually defined as a condition where an individual experiences adverse health effects that he or she believes is due to exposure to objects that emit electromagnetic fields. The aim of this study was to develop a questionnaire that would identify the key symptoms associated with EHS and determine how often these symptoms occur in the general population of the United Kingdom. In the pilot study, an EHS questionnaire was developed and tested. In Study 1 the EHS questionnaire was revised and sent to a randomly selected sample of 20,000 people. Principal components analysis of the symptoms resulted in eight subscales: neurovegetative, skin, auditory, headache, cardiorespiratory, cold related, locomotor, and allergy related symptoms. Study 2 established the validity of the questionnaire in that EHS individuals showed a higher severity of symptoms on all subscales compared to the control group. The two key results of this study were the development of a scale that provides an index of the type and intensity of symptoms commonly experienced by people believing themselves to be EHS and a screening tool that researchers can use to pre-select the most sensitive individuals to take part in their research.

NF1 plexiform neurofibroma growth rate by volumetric MRI: Relationship to age and body weight

OBJECTIVE

To longitudinally analyze changes in plexiform neurofibroma (PN) volume in relation to age and body growth in children and young adults with neurofibromatosis type 1 and inoperable, symptomatic, or progressive PNs, using a sensitive, automated method of volumetric MRI analysis.

METHODS

We included patients 25 years of age and younger with PNs entered in a natural history study or in treatment trials who had volumetric MRI over > or =16 months.

RESULTS

We studied 49 patients (median age 8.3 years) with 61 PNs and a median evaluation period of 34 months (range 18 to 70). The PN growth rates varied among patients, but were constant within patients. Thirty-four patients (69%) experienced > or =20% increase in PN volume during the observation period. PN volume increased more rapidly than body weight over time (p = 0.026). Younger patients had the most rapid PN growth rate.

CONCLUSIONS

Volume increase of plexiform neurofibromas is a realistic and meaningful trial endpoint. In most patients plexiform neurofibroma growth rate exceeded body growth rate. The youngest patients had the fastest plexiform neurofibroma growth rate, and clinical drug development should be directed toward this population. Age stratification for clinical trials for plexiform neurofibromas should be considered.

Effects of mobile phone electromagnetic fields on an auditory order threshold task

The effect of acute exposure to radio frequency electromagnetic fields (RF EMF) generated by mobile phones on an auditory threshold task was investigated. 168 participants performed the task while exposed to RF EMF in one testing session (either global system for mobile communication (GSM) or unmodulated signals) while in a separate session participants were exposed to sham signals. Lateralization effects were tested by exposing participants either on the left side or on the right side of the head. No significant effect of exposure to RF EMF was detected, suggesting that acute exposure to RF EMFs does not affect performance in the order threshold task.

Mood-congruent free recall bias in anxious individuals is not a consequence of response bias

The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modified Stroop task, anxious individuals recalled more threat-related words compared to low-anxious people. This difference was significant even when controlling for the false recall of items that had not been presented during study. These results support the view put forward by Russo, Fox, Bellinger, and Nguyen-Van-Tam (2001) that mood-congruent free recall bias in anxious individuals can be observed if the target material is encoded at a relatively shallow level. Moreover, contrary to Dowens and Calvo (2003), the current results show that the memory advantage for threat-related information in anxious individuals is not a consequence of response bias.

The eyes are sufficient to produce a threat superiority effect

The research described in this article used a visual search task and demonstrated that the eye region alone can produce a threat superiority effect. Indeed, the magnitude of the threat superiority effect did not increase with whole-face, relative to eye-region-only, stimuli. The authors conclude that the configuration of the eyes provides a key signal of threat, which can mediate the search advantage for threat-related facial expressions.

Randomized trial and pharmacokinetic study of pegfilgrastim vs. filgrastim in children and young adults with newly diagnosed sarcoma treated with dose intensive chemotherapy

9020

Background: Daily subcutaneous (SC) filgrastim reduces the duration of severe neutropenia in children receiving dose intensive chemotherapy. A single SC dose of pegfilgrastim may be as efficacious. Methods: We conducted a randomized, non-inferiority trial comparing neutrophil recovery, tolerability, and pharmacokinetics of pegfilgrastim (100 mcg/kg SC once/cycle) to filgrastim (5 mcg/kg SC daily until post nadir ANC >10,000) in children and young adults with newly diagnosed sarcoma treated with vincristine, doxorubicin, and cyclophosphamide (VDC) for cycles 1, 2, 5, 9, 11, 13 alternating with etoposide and ifosfamide (IE) for cycles 3, 4, 6–8, 10, 12, 14. Local control with radiation or surgery was initiated after cycle 5. Serum GCSF concentrations were monitored during cycle 1 and measured by ELISA. Complete blood counts were monitored thrice weekly during cycles 1–4. Cycle duration was collected for all cycles. Results: Accrual has been completed. 34 patients (median age 19 y, range 3–25 y) were enrolled, 28 have completed 4 cycles, and 26 have completed therapy. Growth factor associated toxicity included reversible transaminase elevation and arthralgias and was similar on the 2 treatment arms. For filgrastim (n=13) the median (range) GCSF Cmax was 12 ng/mL (4–16 ng/mL), Css was 7 ng/mL (2–9 ng/mL) and Tmax was 6 h (4–8 h). For pegfilgrastim (n=13), the median (range) GCSF Cmax was 69 ng/mL (11–235 ng/mL), Css was 43 ng/mL (7–151 ng/mL) and Tmax was 28 h (4–168 h). Median (range) neutrophil recovery and cycle duration are presented in the table. Conclusion: Pegfilgrastim was well tolerated. Peak and steady state serum GCSF concentrations were higher in patients receiving pegfilgrastim but more variable. The number of days of severe neutropenia and the cycle duration with single dose pegfilgrastim appear to be at least equivalent to daily filgrastim.

[Table: see text]

No significant financial relationships to disclose.

Anxiety modulates the degree of attentive resources required to process emotional faces

The present study contributes to the ongoing debate over the extent to which attentive resources are required for emotion perception. Although fearful facial expressions are strong competitors for attention, we predict that the magnitude of this effect may be modulated by anxiety. To test this hypothesis, healthy volunteers who varied in their self-reported levels of trait and state anxiety underwent an attentional blink task. Both fearful and happy facial expressions were subject to a strong attentional blink effect for low-anxious individuals. For those reporting high anxiety, a blink occurred for both fearful and happy facial expressions, but the magnitude of the attentional blink was significantly reduced for the fearful expressions. This supports the proposals that emotion perception is not fully automatic and that anxiety is related to a reduced ability to inhibit the processing of threat-related stimuli. Thus, individual differences in self-reported anxiety are an important determinant of the attentional control of emotional processing.

Topoisomerase II-alpha expression increases with increasing Gleason score and with hormone insensitivity in prostate carcinoma

AIM

To investigate and compare topoisomerase II-alpha expression in benign prostatic hyperplasia (BPH), prostate cancer of varying Gleason scores and hormone-insensitive prostate cancer.

METHODS

The immunohistochemical expression of topoisomerase II-alpha antibody in the above-mentioned diagnostic categories was investigated and compared.

RESULTS

Increased expression of topoisomerase II-alpha was seen in the prostate cancers of Gleason scores 7 and 8-10 (p = 0.000) compared with prostate cancers of Gleason score 6 and BPH (p = 0.245). Statistically significant differences were found in the topoisomerase II-alpha gene expression between prostate cancers categorised by Gleason Score. Also, increased expression of topoisomerase II-alpha was seen in the known hormone-resistant prostate carcinomas compared with prostate cancers with no hormone treatment in the subgroup with Gleason scores 8-10, which approached statistical significance (p = 0.081). No statistically significant difference was observed in topoisomerase II-alpha expression between the groups with BPH and prostate carcinoma of Gleason score 6 (p = 0.245).

CONCLUSION

Topoisomerase II-alpha expression was found to increase with the known prognostic marker Gleason score and with hormone insensitivity. Objective evidence is provided for clinical trials with drugs targeting topoisomerase II-alpha to be targeted to patients with prostate cancers of Gleason Score >6 and, in particular, prostate cancers of Gleason Scores 8-10.

Does acute exposure to mobile phones affect human attention?

Recent studies have indicated that acute exposure to low level radiofrequency (RF) electromagnetic fields generated by mobile phones affects human cognition. However, the relatively small samples used, in addition to methodological problems, make the outcomes of these studies difficult to interpret. In our study we tested a large sample of volunteers (168) using a series of cognitive tasks apparently sensitive to RF exposure (a simple reaction task, a vigilance task, and a subtraction task). Participants performed those tasks twice, in two different sessions. In one session they were exposed to RFs, with half of subjects exposed to GSM signals and the other half exposed to CW signals, while in the other session they were exposed to sham signals. No significant effects of RF exposure on performance for either GSM or CW were found, independent of whether the phone was positioned on the left or on the right side.

Selective target processing: Perceptual load or distractor salience?

Perceptual load theory (Lavie, 1995) states that participants cannot engage in focused attention when shown displays containing a low perceptual load, because attentional resources are not exhausted, whereas in high-load displays attention is always focused, because attentional resources are exhausted. An alternative "salience" hypothesis holds that the salience of distractors and not perceptual load per se determines selective attention. Three experiments were conducted to investigate the influence that target and distractor onsets and offsets have on selective processing in a standard interference task. Perceptual load theory predicts that, regardless of target or distractor presentation (onset or offset), interference from ignored distractors should occur in low-load displays only. In contrast, the salience hypothesis predicts that interference should occur when the distractor appears as an onset and would occur for distractor offsets only when the target was also an offset. Interference may even occur in highload displays if the distractor is more salient. The results supported the salience hypothesis.

Focusing on fear: Attentional disengagement from emotional faces

Evidence suggests that anxiety is associated with a shift of visual attention toward threatening stimuli in the environment, such as facial expressions (Mogg & Bradley, 1999). More recent evidence, however, indicates that anxiety may be better characterized by a failure to rapidly disengage the visual attention system away from threat-related facial expressions (Fox, Russo, Bowles, & Dutton, 2001). The present study further investigates this delayed disengagement hypothesis. Results show that high trait-anxious individuals, in contrast to low trait-anxious individuals, take longer to classify peripheral target letters when fearful facial expressions were presented at fixation relative to sad, happy, or neutral expressions. These findings demonstrate a specific tendency to dwell on fear-relevant stimuli, as opposed to negative information in general. These findings are considered from an evolutionary perspective and the possible role of delayed disengagement from threat in the maintenance of anxiety states is also discussed.

Could nursery rhymes cause violent behaviour? A comparison with television viewing

AIMS

To assess the rates of violence in nursery rhymes compared to pre-watershed television viewing.

METHODS

Data regarding television viewing habits, and the amount of violence on British television, were obtained from Ofcom. A compilation of nursery rhymes was examined for episodes of violence by three of the researchers. Each nursery rhyme was analysed by number and type of episode. They were then recited to the fourth researcher whose reactions were scrutinised.

RESULTS

There were 1045 violent scenes on pre-watershed television over two weeks, of which 61% showed the act and the result; 51% of programmes contained violence. The 25 nursery rhymes had 20 episodes of violence, with 41% of rhymes being violent in some way; 30% mentioned the act and the result, with 50% only the act. Episodes of law breaking and animal abuse were also identified. Television has 4.8 violent scenes per hour and nursery rhymes have 52.2 violent scenes per hour. Analysis of the reactions of the fourth researcher were inconclusive.

CONCLUSIONS

Although we do not advocate exposure for anyone to violent scenes or stimuli, childhood violence is not a new phenomenon. Whether visual violence and imagined violence have the same effect is likely to depend on the age of the child and the effectiveness of the storyteller. Re-interpretation of the ancient problem of childhood and youth violence through modern eyes is difficult, and laying the blame solely on television viewing is simplistic and may divert attention from vastly more complex societal problems.

Semantic activation in the absence of perceptual awareness

Participants performed a semantic categorization task on a target that was preceded by a prime word belonging either to the same category (20% of trials) or to a different category (80% of trials). The prime was presented for 33 msec and followed either immediately or after a delay by a pattern mask. With the immediate mask, reaction times (RTs) were shorter on related than on unrelated trials. This facilitatory priming reached significance at prime-target stimulus onset asynchronies (SOAs) of 400 msec or less and remained unaffected by task practice. With the delayed mask, RTs were longer on related than on unrelated trials. This reversed (strategic) semantic priming proved to be significant (1) only at a prime-target SOA of 400 msec or longer and (2) after the participants had some practice with the task. The present findings provide further evidence that perceiving a stimulus with and without phenomenological awareness can lead to qualitatively different behavioral consequences.

Repetition priming effects from attended vs. ignored single words in a semantic categorization task

The present research examines priming effects from a centrally presented single-prime word to which participants were instructed to either attend or ignore. The prime word was followed by a single central target word to which participants made a semantic categorization (animate vs. inanimate) task. The main variables manipulated across experiments were attentional instructions (attend vs. ignore the prime word), presentation duration of the prime word (20, 50, 80 or 100 ms), prime-target stimulus onset asynchrony (SOA; 300 vs. 800 ms), and temporal presentation of instructions (before vs. after the prime word). The results showed (a) a consistent interaction between attentional instructions and repetition priming and (b) a qualitatively different ignored priming pattern as a function of prime duration: reduced positive priming (relative to the attend instruction) for prime exposures of 80 and 100 ms, and reliable negative priming for the shorter prime exposures of 20 and 50 ms. In addition (c), the differential priming pattern for attend and ignore trials was observed at a prime-target SOA of 800 ms (but not at a shorter 300-ms SOA) and only when instructions were presented before the prime word. Methodological and theoretical implications of the present findings for the extant negative priming literature are discussed.

The face of fear: Effects of eye gaze and emotion on visual attention

We investigated whether a fearful expression enhances the effect of another's gaze in directing the attention of an observer. Participants viewed photographs of faces whose gaze was directed ahead, to the left or to the right. Target letters then appeared unpredictably to the left or right. As expected, targets in the location indicated by gaze were detected more rapidly. In nonanxious volunteers the effects of fearful gaze did not differ from neutral gaze, but fearful expression had a more powerful influence in a selected high anxious group. Attention is thus more likely to be guided by the direction of fearful than neutral gaze, but only in anxiety-prone individuals.

The right-to-die movement: extrapolating from the National Hemlock Society U.S.A. membership survey

A national membership survey of Hemlock Society USA was conducted by Fox and Kamakahi (1995). Respondents (N=6398) were asked a variety of questions, but in this paper we perform a longitudinal analysis of the characteristics of Hemlock Society USA members. Hemlock Society USA members are divided into three 5-year cohorts: Early Joiners (11 or more years of membership), Middle Joiners (6 to 10 years membership), and Late Joiners (5 or fewer years of membership). Differences between cohorts are examined and extrapolations made regarding Hemlock Society USA and the Right-to-Die Movement. A series of one-way ANOVAs were used with Scheme post-hoc comparisons as heuristic tools for assessing between-cohort differences. Late Joiners are different from earlier members, but are more like other Hemlock Society USA members than the adult U.S. population at large. Hemlock Society USA members are essentially societal "elites" (based on socio-demographic variables) who work in social environments that are decidedly split on the issue of voluntary suicide and euthanasia.