1. Form of rhabdomyosarcoma occurring mainly in adolescents and young adults
   - alveolar rhabdomyosarcoma

Type of: rhabdomyosarcoma, rhabdosarcoma

• order Heterosomata
• order Heterotrichales
• order Hymenogastrales
• order Hymenoptera
• order Hypericales
• order Hypermastigina
• order Hypocreales
• order Hyracoidea
• order Ichthyosauria
• order Ictodosauria
• order Insectivora
• order Insessores
• order Isoetales
• order Isopoda
• order Isoptera
• order Isospondyli
• order Juglandales
• order Jungermanniales
• order Lagomorpha
• order Laminariales
• order Lechanorales
• order Lepidodendrales
• order Lepidoptera
• order Lichenales
• order Liliales