PMID- 25398679 OWN - NLM STAT- MEDLINE DCOM- 20150723 LR - 20240322 IS - 2044-6055 (Electronic) IS - 2044-6055 (Linking) VI - 4 IP - 11 DP - 2014 Nov 14 TI - Exposure to sodium channel-inhibiting drugs and cancer survival: protocol for a cohort study using the QResearch primary care database. PG - e006604 LID - 10.1136/bmjopen-2014-006604 [doi] LID - e006604 AB - INTRODUCTION: Metastasis from solid tumours is associated with significant morbidity and mortality, and is the leading cause of cancer-related deaths. Voltage-gated sodium channels (VGSCs) are drug targets for the treatment of epilepsy. VGSCs are also present in cancer cells, where they regulate metastatic cell behaviours, including cellular movement and invasion. Treating cancer cells with the VGSC-inhibiting anticonvulsant phenytoin reduces cellular invasion and migration. Together, these suggest that VGSCs may be useful targets for inhibiting metastasis. The purpose of this study is to test the hypothesis that use of VGSC-inhibiting drugs will reduce metastasis, and therefore increase survival time in patients with cancer. METHODS AND ANALYSIS: A cohort study based on primary care data from the QResearch database will include patients with one of the three common tumours: breast, bowel and prostate. The primary outcome will be overall survival from the date of cancer diagnosis. Cox proportional hazards regression will be used to compare the survival of patients with cancer taking VGSC-inhibiting drugs (including anticonvulsants and class I antiarrhythmic agents) with patients with cancer not exposed to these drugs, adjusting for age and sex. Exposure to VGSC-inhibiting drugs will be defined as having at least one prescription for these drugs prior to cancer diagnosis. High and low exposure groups will be identified based on the length of use. A number of sensitivity and secondary analyses will be conducted. ETHICS AND DISSEMINATION: The protocol has been independently peer-reviewed and approved by the QResearch Scientific Board. The project has also been approved by the University of York Ethical Review Process. The results will be presented at international conferences and published in an open access peer-reviewed journal, in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria. CI - Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions. FAU - Fairhurst, Caroline AU - Fairhurst C AD - Department of Health Sciences, University of York, York, UK. FAU - Watt, Ian AU - Watt I AD - Department of Health Sciences, University of York, York, UK Hull York Medical School, York, UK. FAU - Martin, Fabiola AU - Martin F AD - Hull York Medical School, York, UK Department of Biology, University of York, York, UK. FAU - Bland, Martin AU - Bland M AD - Department of Health Sciences, University of York, York, UK. FAU - Brackenbury, William J AU - Brackenbury WJ AUID- ORCID: 0000-0001-6882-3351 AD - Department of Biology, University of York, York, UK. LA - eng GR - WT_/Wellcome Trust/United Kingdom GR - G1000508/MRC_/Medical Research Council/United Kingdom GR - 097829/WT_/Wellcome Trust/United Kingdom PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20141114 PL - England TA - BMJ Open JT - BMJ open JID - 101552874 RN - 0 (Sodium Channel Blockers) SB - IM MH - Adult MH - Breast Neoplasms/*drug therapy MH - *Clinical Protocols MH - Cohort Studies MH - Colonic Neoplasms/*drug therapy MH - *Databases, Factual MH - Female MH - Humans MH - Male MH - Primary Health Care/methods MH - Prostatic Neoplasms/*drug therapy MH - Sodium Channel Blockers/*therapeutic use MH - Survival Analysis PMC - PMC4244419 OTO - NOTNLM OT - PRIMARY CARE OT - STATISTICS & RESEARCH METHODS EDAT- 2014/11/16 06:00 MHDA- 2015/07/24 06:00 PMCR- 2014/11/14 CRDT- 2014/11/16 06:00 PHST- 2014/11/16 06:00 [entrez] PHST- 2014/11/16 06:00 [pubmed] PHST- 2015/07/24 06:00 [medline] PHST- 2014/11/14 00:00 [pmc-release] AID - bmjopen-2014-006604 [pii] AID - 10.1136/bmjopen-2014-006604 [doi] PST - epublish SO - BMJ Open. 2014 Nov 14;4(11):e006604. doi: 10.1136/bmjopen-2014-006604.