spindle cell sarcoma chemotherapymalignant spindle cell carcinomamalignant spindle cell neoplasmspindle cell malignant melanomamalignant spindle cell tumourspindle cell mesotheliomaspindle cell lymphomaatypical spindle cellspindle cell neoplasm treatmentspindle cell tumors treatmentcellular spindle cell neoplasmatypical spindle cell neoplasm