AbstractThe ovaries of 470 patients obtained for various indications at operation revealed 178 with 193 ovarian cysts and tumors ‐ including 63 serous, 23 endometrial, and 27 mucinous ‐ as well as 103 with tubal (serous), 35 with endometrial, and 2 with cervical (mucinous) epithelial inclusions. A very high frequency of transformation of mucinous epithelial inclusions into cysts and tumors contrasted with about 40% similar transformation of serous and endometrial inclusions into cysts and tum