Scrotal Fetus in Fetu in a Newborn: A Rare Case Report.

Fetus in fetu is a rare phenomenon of infancy, separate from conjoined twins, teratomas, and acardiac twins. The pathogenesis is not well understood but has been theorized to originate from either the involution of a twin or the differentiation of a teratoma. While the majority of these are found in the retroperitoneum, the presence of a fetus in fetu within the scrotum is exceedingly rare. We present the diagnosis and management of a case of fetus in fetu in the scrotum of a newborn male including radiologic imaging and pathologic examination.