A tumor arising from connective tissue is called a sarcoma because sarcomas originate from mesenchymal cells which form connective tissues such as bone, muscle, fat, and cartilage. Unlike carcinomas, which arise from epithelial cells, sarcomas are distinct in their tissue origin and biological behavior. Recognizing this differentiation is crucial for diagnosis, surgical planning, and treatment, as sarcomas may require wide local excision with clear margins to prevent recurrence. Understanding tumor origin guides the surgeon in selecting appropriate resection techniques and anticipating potential complications related to connective tissue involvement.

Reference: Robbins Basic Pathology, Kumar V. et al., 10th Edition.