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

### Input Text: Pediatric alveolar rhabdomyosarcoma is characterized by a chromosomal translocation that fuses parts of the PAX3 and FKHR genes .
### Output Text:
<span class="disease">Pediatric alveolar rhabdomyosarcoma</span> is characterized by a chromosomal translocation that fuses parts of the PAX3 and FKHR genes . 