RB1 and spindle cell liposarcoma: His examination and operative evaluation were initially consistent with a recurrent internal laryngocele, but after pathologic evaluation, the diagnosis of well-differentiated spindle cell liposarcoma was made based on the histologic features as well as cluster of differentiation 34 (CD34) positivity, amplification of murine double minute-2 (MDM2) by fluorescence in situ hybridization (FISH), retained retinoblastoma (RB) protein expression, and negativity for signal transducer and activator of transcription 6 (STAT6).