This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breast, Subject name: Pathology
"Biphasic pattern" on histology is seen in Which tumor 
Select and explain. 
A. Rhabdomyosarcoma, B. Synol cell sarcoma, C. Osteosarcoma, D. Neurofibroma
B: Synol cell sarcoma
Answer: B: Synol cell sarcoma 
Explanation: Biphasic pattern of synol sarcoma consists of an admixture of glandular structures lined by cuboidal or columnar epithelium set in a sarcomatous stroma. some occult cases clusters of plump cells with pale cytoplasm are present in a spindle cell stroma.These nests of cells are accentuated by reticulin stain.Monophasic pattern of synol sarcoma is characterized by monomorphic population of spindle shaped cells arranged in fascicles. he cells contain uniform tapering nuclei and pale cytoplasm. Mitotic figures are present in variable numbers. Other striking features include: - Presence of mast cells - Calcification with or without ossification. Calcification is usually preceded by hyalinization.