spindle cell neoplasm treatmentpleomorphic spindle cell neoplasmbenign spindle cell neoplasmatypical spindle cell neoplasmcellular spindle cell neoplasmmalignant spindle cell tumormalignant spindle cell tumourmyxoid spindle cell neoplasmspindle cell melanoma treatmentspindle cell tumormetastatic spindle cell melanomaatypical spindle cell tumor