Yolk Sac Tumor of the Ovary in 18 Egyptian Cases: Does It Really Differ?

Abstract

Background: Ovarian Yolk sac tumor (OYST) is a rare entity of malignant ovarian germ cell tumors (MOGCT). Abdominal pain, a rapidly growing distending mass or irregular vaginal bleeding is the main presentation. Serum AFP is elevated in nearly all cases. The standard management is fertility preserving surgery with adjuvant chemotherapy. Aim of Work: To report and analyze retrospectively recorded cases that were either treated at National Cancer Institute/Egypt or referred there for advice about therapy. Materials and Methods: This is a retrospective single-institutional analysis of 18 cases of OYST treated at National Cancer Institute-Cairo University from January 2011 till December 2015. The clinical and pathological characteristics, treatment, and outcomes of these patients were analyzed. Results: Data from eighteen patients were obtained. The median age was 18 years (range: 15 - 22). Abdominal pain was the most common presentation (89%). The mean tumor size was 21cm (range: 8 - 30 cm). Eleven of our cases (61%) were stage I, seven cases and (39%) were stage IV at presentation. Fifteen cases (83%) underwent fertility preserving procedure & the standard surgical staging. Panhysterectomy & formal staging procedure was done only in two cases (11%). One case (6%) underwent bilateral salpingo-oophorectomy. 2 cases (11.1%) only underwent lymph node biopsy. 11 patient (61.1%) showed pure type YST while mixed type was present in the remaining 7 cases (38.8%): Dysgerminoma (one case, 5.6%), Dysgerminoma + immature teratoma (one case, 5.6%), Immature teratoma (2 cases, 11.1%) and Teratoma (3 cases, 16.7%). AFP was extremely elevated in all cases at presentation (median 4191 ng/mL; ranging: 725 ng/mL - 402,908 ng/mL). It showed decreased level after surgery (median 145 ng/ mL; ranging: 2 ng/mL - 38,000 ng/mL) & normalized after chemotherapy except for progressive disease. All cases started BEP regimen after surgery with complete remission in twelve cases. In follow up period (median 17 months; ranging: 2 - 48 months) two patients relapsed; the mean overall survival time was 34.2 and progression free survival was 33.84 months respectively. Conclusion: Ovarian yolk sac tumors are rare neoplasms. Surgery with adjuvant chemotherapy is the standard management. AFP is important for diagnosis, monitoring response to treatment and predicting relapse.