Résumé : The objective of this retrospective study of prospectively registered patients was to determine the usefulness and efficacy of noninvasive ventilation (NIV) in cancer patients admitted to the medical intensive care unit of an European cancer hospital for a medical complication, as reflected in discharges from the intensive care unit (ICU) and from hospital. The subjects were a total of 40 consecutive cancer patients (28 with solid tumours and 12 with haematological malignancies) who required immediate or delayed NIV. Variables relating to demographic parameters, severity scores, cancer characteristics, intensive care data and hospital discharge were recorded. The complications making NIV necessary were hypoxaemic pneumonia in 32.5%, hypercapnic ventilatory failure in 30%, multifactorial respiratory failure in 17.5%, acute haemodynamic oedema in 10%, acute respiratory distress syndrome in 2.5%, alveolar haemorrhage in 2.5%, pulmonary embolism in 2.5% and lysis pneumopathy in 2.5%. Most of the patients, 57.5% and 42.5%, respectively, were discharged from the ICU and from the hospital. Among the 10 patients (25%) who required salvage invasive mechanical ventilation, only 1 was discharged from hospital. Sixty-four per cent of the solid tumour patients and 42% of those with haematological malignancies were discharged from the ICU and 50% and 25%, respectively, from the hospital. NIV thus appears to be an effective form of ventilatory support for cancer patients, including those with solid tumours.