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Micronucleus (MN) formation is routinely used as a biodosimeter for radiation exposures and has historically been used as a measure of DNA damage in cells. Strongly correlating with dose, MN are also suggested to indicate radiation quality, differentiating between particle and photon irradiation. The “gold standard” for measuring MN formation is Fenech’s cytokinesis-block micronucleus (CBMN) cytome assay, which uses the cytokinesis blocking agent cytochalasin-B. Here, we present a comprehensive analysis of the literature investigating MN induction trends in vitro, collating 193 publications, with 2476 data points. Data were collected from original studies that used the CBMN assay to quantify MN in response to ionizing radiation in vitro. Overall, the meta-analysis showed that individual studies mostly have a linear increase of MN with dose [85% of MN per cell (MNPC) datasets and 89% of percentage containing MN (PCMN) datasets had an R2 greater than 0.90]. However, there is high variation between studies, resulting in a low R2 when data are combined (0.47 for MNPC datasets and 0.60 for PCMN datasets). Particle type, species, cell type, and cytochalasin-B concentration were suggested to influence MN frequency. However, variation in the data meant that the effects could not be strongly correlated with the experimental parameters investigated. There is less variation between studies when comparing the PCMN rather than the number of MNPC. Deviation from CBMN protocol specified timings did not have a large effect on MN induction. However, further analysis showed less variation between studies following Fenech’s protocol closely, which provided more reliable results. By limiting the cell type and species as well as only selecting studies following the Fenech protocol, R2 was increased to 0.64 for both measures. We therefore determine that due to variation between studies, MN are currently a poor predictor of radiation-induced DNA damage and make recommendations for futures studies assessing MN to improve consistency between datasets.

Introduction National guidelines recommend that shared decision making be employed where several treatment or supportive care options are available to the patients with cancer. Shared decision making is associated with positive outcomes for patients including reduced decision regret surrounding their treatment and reduction of unrealistic expectations. Optimising shared decision making in situations where cancer is no longer curable may facilitate the discussion about not only the aims of treatment but also the patient9s life goals and how their treatment options may affect these. Aim to evaluate the Cancer-Goal Use In DEcisions (Can-GUIDE) web-based communication/decision aid as a resource for facilitating goals of care conversations and shared decision making in the context of incurable cancer. Method A pre-test post-test pilot study to assess the benefit of Can-GUIDE on patient experience and shared decision making. The quality of the decision making process is currently being assessed by determining the effect on patient decision self-efficacy, decision conflict, preparation for decision making and perceived involvement in shared decision making with their clinician. Oncology clinician opinion will be sought to determine whether patient responses to the package helped guide GOC conversations within their consultations. Furthermore, GPs will be surveyed to determine the usefulness of receiving a tool documenting GOC conversations within oncology consultations. The views of all participant groups surrounding the usability and acceptability of Can-GUIDE are also being investigated. Results Currently, 14 patients have been recruited for the study with 4 withdrawn due to progressing disease or non-compliance with protocol. Data collection is due to complete March 2018 with a total of 40 patients recruited. Conclusions If our pilot results demonstrate the potential value of Can-GUIDE a fully powered randomised controlled trial will be conducted to tests its effectiveness on improving patient-centred outcomes.