Prognosis of Eight Chinese Cases of Primary Vaginal Yolk Sac Tumor with a Review of the Literature

Background: Primary vaginal yolk sac tumor is a rare malignancy in the pediatric population, and adiagnostic challenge and appropriate initial treatment remains unsolved. The aim of this study was to investigatethe clinicopathologic features, treatment and prognosis of this tumor. Materials and
Methods: Eight cases ofprimary vaginal yolk sac tumor were reported with a literature review.
Results: There were 4 pure yolk sactumor cases and four mixed germ cell tumors containing yolk sac tumor element, including two cases withembryonal carcinoma and two cases with embryonal carcinoma and dysgerminoma. Partial vaginectomy wasperformed in four cases and all patients received chemotherapy. 85 cases in literatures were reviewed and 9cases were misdiagnosed. Follow-up data was available in 77 cases and 5-year overall survival rate was 87.6%.5-year survival rate of biopsy with chemotherapy, conservative surgery with chemotherapy and radical surgerywith chemotherapy was 91.1%, 100% and 28.6%, respectively (p<0.001). Compared to cases without relapse ormetastasis after initial treatment, patients with relapse or metastasis had a shorter overall survival (35.6% vs96.6%, p<0.001).
Conclusions: Mixed germ cell tumor containing yolk sac tumor element was not uncommonand partial vaginectomy may be a good choice for primary vaginal mixed yolk sac tumor type to eradicate localtumor cells and provide complete information for pathological diagnosis and postoperative adjuvant therapy.