The prognostic value of testicular biopsy in childhood acute lymphoblastic leukemia: a report from the Childrens Cancer Study Group.

One of the objectives of Childrens Cancer Study Group (CCSG) study 141 (CCG-141) was to determine the frequency of occult testicular leukemia (TL) after 3 years of disease-free survival (DFS) and to retreat boys with occult TL to prolong their subsequent DFS. Of the 494 boys entered on study, 255 (51.6%) were in complete continuous remission (CCR) 3 years after entering remission and an additional eight were in CCR 3 years after localized extramedullary relapse and retreatment; 263 boys were eligible for testicular biopsy. Elective testicular biopsy was performed on 235 (89.4%) boys. Of the 204 (86.8%) boys with negative biopsies, 175 (85.8%) remained in CCR 10 to 12 years after diagnosis and 25 (12.3%) relapsed, 11 (44%) of whom died. Isolated overt TL occurred in four (2.0%) and all remained in CCR 22+ to 60+ months after re-treatment. Of the 26 boys with occult TL, 16 (62%) remained in CCR. Ten (38%) relapsed despite local testicular irradiation and systemic re-treatment; six of the 10 died. Of the 26 ...