Histopathology:
MACROSCOPIC DESCRIPTION: "Left orchidectomy specimen": Testis with spermatic cord weighing 56g and measuring 45x25x30mm. Spermatic cord 80x12mm. Epididymis 38x14x12mm. The specimen initially arrived fresh to the laboratory and some tissue was sent for flow cytometry.
On cut section, within the lower pole of the testis, there is a reasonably well-circumscribed pale tan nodule 30x30x25mm. Patchy haemorrhage on cut surface. The nodule abuts the tunica albuginea but does not appear to extend into it. It is not seen on the surface of the tunica albuginea and the tunica vaginalis is not adherent. Epididymis appears normal and the tumour does not appear to extend to the rete.
MICROSCOPIC DESCRIPTION:
Sections show testis, epididymis and spermatic cord. There is infiltration of the testicular parenchyma by a diffuse infiltrate of plasmacytoid cells that is surrounding and destroying seminiferous tubules. The cells have round, eccentrically-placed nuclei with "clockface" chromatin and amphophilic cytoplasm. A perinuclear hof is seen in some cells; others have small nucleoli. Scattered Russell bodies and Dutcher bodies are also present.
There is wide infiltration of the testicular parenchyma, beyond the nodule seen macroscopically. The infiltrate is also present within but does not extend through adjacent tunica albuginea. Tumouir is not seen within the epididymis or at the spermatic cord resection margin.
Immununohistochemical staining for CD 138 shows strong positive staining within tumour cells. CD79a shows patchy positive staining and there is Kappa light chain restriction. Staining for CD20 is negative in tumour cells.
DIAGNOSIS:
Left testis: Plasmacytoma/Myeloma with kappa light chain restriction; involving tunica albuginea; epididymis spermatic cord margin clear of tumour.