Before Consent: Qualitative Analysis of Deliberations of Patients With Advanced Cancer About Early-Phase Clinical Trials

PURPOSE

Patients with advanced cancer and oncologists deliberate about early-phase (EP) trials as they consider whether to pursue EP trial enrollment. We have limited information about those deliberations and how they may facilitate or impede trial initiation. This study describes these deliberations and their relationship to trial initiation.

PATIENTS AND METHODS

We collected longitudinal, ethnographic data on deliberations of patients with advanced cancer at two academic medical centers. We used constant comparative and framework analyses to characterize the deliberative process and its relationship to trial initiation.

RESULTS

Of 96 patients with advanced cancer, 26% initiated EP enrollment and 19% joined a trial. Constant comparative analysis revealed two foci of deliberation. Setting the stage focused on patient and physician support for EP trial involvement, including patients' interest in research and oncologists' awareness of trials and assessment of patient fit. Securing a seat focused on eligibility for and entrance to a specific trial and involved trial availability, treatment history, disease progression, and enrollment timing. Patients enrolled in a trial only when both stages could be successfully navigated.

CONCLUSION

Ethnographic data revealed two foci of deliberation about EP trial enrollment among patients with advanced cancer. Physician support played a consequential role in both stages, but enrollment also reflected factors beyond the control of any specific individual. Insights from this study, combined with other recent studies of trial enrollment, advance our understanding of the complex process of EP trial accrual and may help identify strategies to improve rates of participation.

Cloning and characterization of SK2 channel from chicken short hair cells

In the inner ear of birds, as in mammals, reptiles and amphibians, acetylcholine released from efferent neurons inhibits hair cells via activation of an apamin-sensitive, calcium-dependent potassium current. The particular potassium channel involved in avian hair cell inhibition is unknown. In this study, we cloned a small-conductance, calcium-sensitive potassium channel (gSK2) from a chicken cochlear library. Using RT-PCR, we demonstrated the presence of gSK2 mRNA in cochlear hair cells. Electrophysiological studies on transfected HEK293 cells showed that gSK2 channels have a conductance of approximately 16 pS and a half-maximal calcium activation concentration of 0.74+/-0.17 microM. The expressed channels were blocked by apamin (IC(50)=73.3+/-5.0 pM) and d-tubocurarine (IC(50)=7.6+/-1.0 microM), but were insensitive to charybdotoxin. These characteristics are consistent with those reported for acetylcholine-induced potassium currents of isolated chicken hair cells, suggesting that gSK2 is involved in efferent inhibition of chicken inner ear. These findings imply that the molecular mechanisms of inhibition are conserved in hair cells of all vertebrates.

Neuroanatomical tract tracing provides histological verification of neuron loss following cytotoxic lesions

In the present study we report a neuroanatomical procedure that provides direct histological verification of the extent of neuron loss following cytotoxic lesions of the lateral subdivision of the habenular complex (Lhb). Following kainic acid-induced lesions of Lhb neurons, the fluorescent retrograde tracer Fluoro-Gold was injected into the ventral midbrain where many medial habenula (Mhb) and Lhb neurons project. The absence of retrogradely labeled neurons in the Lhb indicated the extent of neuron loss there, and the presence of Fluoro-Gold-labeled neurons in the Mhb indicated that its neurons were intact. The extent of neuron loss in the Lhb was significantly correlated with behavioral data. Retrograde tract tracing can be used as an effective histological tool to verify the extent of neuron loss following a lesion procedure.