A microscopic feature of seminoma include all of the following except -
Gland formation
Lymphocytic infiltration
Monomorphic cells
Destruction of seminiferous tubules
Microscopic features of Seminoma

Sheets of uniform (monomorphic) cells, i.e., seminoma cells,
Sheets are divided into poorly demarcated lobules by delicate septa of fibrous tissue.
Septa is infiltrated with T- lymphocytes.
Sometimes prominent granuloma

Seminoma cell has the following features

Large and round to polyhedral.                            
Distinct cell membrane                                            
Clear or watery appearing cytoplasm.                
A large central nucleus with one or two prominent nuclei.
Cytoplasm contains glycogen.
 Placental alkaline phosphatase and keratin positive.