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Background In 2014, a bushfire ignited the Hazelwood coalmine in regional Victoria, Australia, shrouding nearby communities in smoke for 6 weeks. In this study, we examined whether survival decreased among people with cancer in smoke-exposed areas.Methods We identified cancers diagnosed between January 2009 and February 2014, the start of the coalmine fire, from the Victorian Cancer Registry. Tumours were grouped by location as well as subtypes for breast and lung cancers. Smoke exposure was determined by the daily average of PM 2.5 per 10 µg/m3 attributable to the mine fire at Statistical Area level 2. Survival effects were analysed using a Cox proportional hazards frailty model.Results There was no detectable effect of fire-related PM 2.5 on overall cancer survival. There was weak evidence that fire-related PM2.5 exposure reduced survival among women with breast cancer (HR: 1.18, 95% CI 1.00 to 1.38 per 10 µg/m3 of PM2.5). No other effects were detectable.Conclusion We found limited evidence that smoke from the Hazelwood coal mine fire reduced survival among people living with cancer. The association with reduced survival among women with breast cancer may be a chance finding. However, this does not rule out an effect and further analyses should follow when more data become available or following other similar disasters.