Pathology Quiz Online

                   March 2005             Case - 45

                                                    Dr  Sampurna Roy  MD 

              Clinical History:  A 55 year old female with a rapidly growing palpable tender solitary mass of

          2 months  duration, in the triceps muscle of the left arm . The lesion is 3cm in diameter.

         There is no history of trauma.

             Gross features:  Poorly demarcated firm scarlike induration (3cm x 2.5 x 0.5) involving muscle

         and overlying muscle fascia.

             Clues to diagnosis: Alternating areas of well preserved muscular fibres and strands of

        proliferating spindle shaped cells (checkerboard- pattern). Uni and binucleated ganglion-like cells.

            Immunohistochemistry: Spindle cells are positive for smooth muscle actin but negative for desmin

        Ganglion-like cells are positive for vimentin but negative for smooth muscle actin and desmin.

                                    DIAGNOSIS: