Background: Decision to transfer patients (pts) with solid cancer to intensive care unit (ICU) is still controversial and based of several considerations. Few studies evaluated the outcome of these patients. The aim of this study was to identify prognostic factors 30-day mortality for pts with solid cancer admitted to ICU. Methods: We conducted a retrospective cohort study of all consecutive pts with solid cancer admitted to ICUs of Bordeaux University Hospital, between January 2010 and December 2015. The study end point was 30-day mortality. Logistic regression analysis was performed to identify independent risk factors. Secondary end points were the description of the characteristics and outcomes of pts, ethical practices, and the study of risk factors of non-resumption of anti-tumoral treatment. Results: We included 235 patients with solid tumors: lung (33%), head-and-neck(23%), colorectal cancer (17%), renal cell carcinoma (17%). Most of them were in metastastic setting (60%).The most common causes of ICU admission were sepsis (56%) and/or respiratory failure (52%). During ICU, 92 pts (39%) required vasopressors, 51 pts (22%) non-mechanical ventilation, 33 pts (14%) OptiFlow, and 61 pts (26%) mechanical ventilation. ICU, 30-day, 90-day mortality rates were 24%, 36% and 50% respectively. After ICU stay, 44% of pts had restarting an anti-tumoral treatment. In univariate analysis, common prognostic factors of 30-day mortality and absence of resumption of anti-tumoral treatment were the number of organ failure (p = 0,005) and SAPS 2 score (p < 0,001). In multivariate analysis and after excluding SAPS 2 score, two or more organ failures (p = .005) and being under non-curative care (p = 0.028) were independent prognostic factors of 30-day mortality. Limitation of life-sustaining therapy was decided for 23% and 43% of pts before the admission and during the ICU stay, respectively. Conclusions: Our results indicate that the discussion of the admission in ICU should be based on the severity of the acute illness, while considering the stage palliative or curative of treatment. The number of organ failures is a variable quickly evaluable that can help oncologists and intensive care specialists in their decision.