In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: Five patients with carcinoma developed thrombotic microangiopathy ( characterized by renal insufficiency , microangiopathic hemolytic anemia , and usually thrombocytopenia ) after treatment with cisplatin , bleomycin , and a vinca alkaloid .
### Output Text:
Five patients with carcinoma developed thrombotic microangiopathy ( characterized by renal insufficiency , microangiopathic hemolytic anemia , and usually thrombocytopenia ) after treatment with <span class="chemical">cisplatin</span> , <span class="chemical">bleomycin</span> , and a <span class="chemical">vinca alkaloid</span> . 