Clinical History:  A 48-year-old multiparous woman consulted her physician because of increasing abdominal girth. On physical examination, a large pelvic mass was detected. An abdominal ultrasound revealed it to be a complex cyst. A serum CA125 was elevated. The patient was taken to the Operating Room where a laparotomy and a right salpingo-oophorectomy was performed. The surgeon requested an intraoperative consultation from the surgical pathologist on call.

Questions:

1. Figure 2a depicts the gross appearance of the right ovarian mass. A 35 cm cystic mass was identified in the right ovary. When the mass was opened it contained over 1000 ml of mucinous and hemorrhagic fluid. The tumor was composed of multiple cysts ranging in size from 2 mm to 15 cm, some with smooth, thin walls and others with thickened, solid walls. From which area would you sample this specimen?

2. Figure 2b depicts the microscopic appearance of the frozen section. What is your diagnosis?

3. What is the significance of the elevated CA125?

4. Based on the diagnosis rendered by the Pathologist while the patient was still under anesthesia, the surgeon decides to do a staging procedure that includes a total abdominal hysterectomy, left salpingo-oophorectomy, omentectomy and multiple peritoneal biopsies. In addition, peritoneal washings were sent for cytologic evaluation. Due to the large size of the tumor, many sections were taken (1 for each cm). One of these is shown in Figure 2c. How is the histology different than that seen in Figure 2b? What is your diagnosis now?

5. What is the general prognosis of this lesion?