“…To our knowledge, there have been 25 reports on 45 ovarian collision tumors in English language literature, 1–6,9–25 since YM Bhende reported a Brenner tumor in the wall of a serous cystadenoma in 1947 9 . The histological findings were described for all 45 ovarian collision tumors, with 14 combinations of teratomas and cystadenomas, 9 teratomas and cystadenocarcinomas, 12 cystadenomas/cystadenocarcinomas and other tumors, 6 teratomas and other tumors, and 4 other extremely rare combinations 4,10–12 . Diagnostic imaging was shown for 25 tumors, including 17 MRI, 3 CT, and 5 ultrasonography scans 2,5,6,13 .…”