Introduction: Intensive Care unit admission may be required by patients with organ failure due to a newly diagnosed cancer or by cancer patients suffering a complication of chemotherapy or bone marrow transplantation.General Oncology: Patients with organ failure due to newly diagnosed cancer may require Intensive Care unit admission for immediate chemotherapy and supportive Care. In this patient population, mortality is determined by the nature and number of organ failures, not the nature or stage of malignancy.The overall mortality for patients who require Intensive Care as a consequence of inpatient chemotherapy is approximately 50 percent. Respiratory failure is the most common complication leading to ICU admission and is also the leading no relapse cause of mortality following chemotherapy or bone marrow transplantation. Other common reasons for transfer of oncology patients to the ICU include sepsis, pulmonary edema, electrolyte disturbances, and alterations in mental status, acute airway obstruction, adverse reactions to medication, and the need for postoperative observation.Bone Marrow Transplantation: As many as 40 percent of bone marrow transplant recipients develops one or more complications that require transfer to an ICU. Respiratory failure is the most common reason for transfer; other reasons include pneumonia, sepsis, mucositis, and intracranial hemorrhage, acute graft-versus-host disease, and cardiac dysfunction, veno-occlusive disease of the liver and adverse reactions to drugs.Conclusion: In accordance with patient preferences, transfer to an ICU is often appropriate for cancer chemotherapy or BMT recipients who develop a potentially life-threatening complication. Patients who require mechanical ventilation longer than 24 hours are likely to die in the hospital. Prognosis should be reassessed at frequent intervals with particular attention to the development of multiple organ dysfunctions.