Case study: A young man in his twenties who had just graduated from college was diagnosed with a very malignant lymphoma last year and had undergone chemotherapy several times. When he was admitted to our department, he was in respiratory failure and required ventilator-assisted breathing. After 5 days of treatment, his condition continued to deteriorate and his family was already thinking of giving up. Does such a patient still need to be actively resuscitated? I and the family decided after full communication that the patient needed to be re-evaluated, we took the transfer ventilator, and the family took a huge risk to give the patient another CT, combined with the patient’s condition, considering that the patient’s lung infection was a rare clinical Pneumocystis carinii pneumonia, and gave cotrimoxazole treatment, the patient’s condition was quickly controlled, and a few dozen dollars of medicine saved this young life. The patient’s chest CT (Feb. 13), the patient’s chest CT (Feb. 22), thus it seems that some critically ill tumor patients admitted to ICU still have a chance of survival. So which tumor patients need to be treated in ICU? Generally speaking, some of the tumor patients who need to be admitted to ICU are those who need to be closely monitored for post-operative complications after surgery. Tumor surgery is relatively complex and long, especially for elderly patients with many preoperative comorbidities, so they need to be admitted to ICU after surgery to make the perioperative period safer and to help them get through the difficult period of surgery. The other part is tumor patients who need close monitoring during tumor treatment or need short-term life support for various organs. For example, head and neck lymphoma patients with tracheal intubation for chemotherapy in ICU; patients with various tumor critical illnesses, such as leukopenia, fever, infection, respiratory insufficiency, acute renal insufficiency during tumor treatment; and patients with combined acute reversible diseases who are likely to recover after a few days or short term ICU treatment. There is also a group of patients whose families are torn and who make it difficult for doctors to judge their prognosis. Like the two cases I mentioned earlier, it seems that ICU admission is no longer necessary according to general principles, but the patient eventually recovered and was discharged. Therefore, when facing such a critically ill oncology patient, we need to inform the family that according to the experience of ICU in domestic and foreign oncology hospitals, when the prognosis of this critically ill oncology patient cannot be judged, it is possible to be admitted to ICU after at least 3-7 days of active treatment, and it is very important that the doctor should actively and dynamically evaluate the patient during this process, and if the treatment improves, the patient can continue active treatment, and if the evaluation of treatment is ineffective, the family should be promptly The family should be informed of the option of hospice care. The famous American Journal of Critical Care Medicine once published an article titled – You never know what kind of surprise your (oncology) patient will give you! Yes, when dealing with a patient with critical oncology, even if the patient is very critical, do not give up lightly. If the patient has the chance to be admitted to ICU, he/she should try to receive at least 3 days of full treatment in ICU and then be evaluated according to the patient’s condition.