Malignant tumor patients are at high risk of medical adhesive-related skin injury（MARSI）.MARSI can cause local skin ulceration, increase the difficulty of fixation and maintenance frequency, even cause unplanned extubation, and increase the pain and economic burden of the patient's re-installation.Malignant tumor patients with long-term PICC are prone to MARSI.CaviionTM can form a protective film on the skin.Applying CaviionTM before using the adhesive can effectively protect the skin and reduce the occurrence of rash.In China, CaviionTM is mostly used in infants and young children, but adults lack corresponding report and application data.Therefore, it is necessary to carry out corresponding randomized controlled study on adult patients, especially malignant tumors

The incidence of medical viscose-related skin injury after PICC intubation is as high as 33.15%. The main types of injury are mechanical injury, moisture-related skin injury, contact dermatitis 8.02%, folliculitis.After radiotherapy and chemotherapy, patients with malignant tumors interfere with the formation of new damaged skin cells.Large doses of immunosuppressive agents further weaken the skin barrier and are prone to skin metabolism and immune function disorder.In this study, patients with malignant tumor after PICC intubation were randomly assigned.The experimental group uses CaviionTM, and the control group does not use CaviionTM. Observe the skin condition one month after the tube placement

Inclusion Criteria:

• For malignant tumor patients newly implanted with PICC,indwelling catheter for more than 1 month，Conduct catheter maintenance in my hospital during observation

Exclusion Criteria:

• People with skin disease around PICC tube，Psychopath