Mondo Description A myeloid or more commonly lymphoid leukemia (acute or chronic) affecting the testis. Microscopically, there is interstitial infiltration of the testis by leukemic cells. Acute lymphoblastic leukemia with testicular involvement is not uncommon in boys. Sometimes (up to 10% of the cases), testicular involvement may be the initial manifestation of relapsed acute lymphoblastic leukemia. --03