Splenogonadal fusion

Splenogonadal fusion is a rare congenital malformation that involves an abnormal connection between the spleen and the gonad. It manifests itself as a mass consisting of splenic and testicular or ovarian tissue. Splenogonadal fusion has been classified into two types; continuous, where there is a direct connection between spleen and gonad; and discontinuous, where ectopic splenic tissue is attached to the gonad, but there is no connection to the spleen.

Although this malformation affects both sexes, it is more common in males. It is rarely diagnosed pre-operatively, and surgery is usually necessary to determine if it is malignant. Historically, there have been several cases where a testicular swelling has resulted in an unnecessary orchiectomy due to suspicion of a testicular neoplasm. Anyway, the splenic tissue can be severed from the tunica albuginea in order to prevent an orchiectomy.

Roughly, only 150 cases of splenogonadal fusion have been documented. The anomaly was first mentioned by pathologist Eugen Bostroem in 1883, but it wasn't until 1889 when a Dr. Pommer described the malformation in detail.