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: It is the third urinary tract cancer reported in association with cyclophosphamide treatment for nonmalignant disease .
### Output Text:
It is the third urinary tract cancer reported in association with <span class="chemical">cyclophosphamide</span> treatment for nonmalignant disease . 