The need for a second-look operation was questioned (375,376). It seems not to be justified in patients who received chemotherapy in an adjuvant setting, because chemotherapy in these patients is effective. Second-look laparotomy in patients with macroscopic residual disease at the start of chemotherapy may be of value in selected patients, as some patients may have residual mature teratoma and are at risk of growing teratoma syndrome, a rare complication of immature teratomas (400,401). Cancers can arise at a later date in residual mature teratoma. It is important to resect any residual mass and exclude persistent disease because further chemotherapy may be indicated. The principles of surgery are based on the much larger experience of surgery in males with residual masses following chemotherapy for germ cell tumors with a component of immature teratoma (402). Mathew et al. reported their experience of laparotomy in assessing the nature of postchemotherapy residue in ovarian germ cell tumors. Sixty-eight patients completed combination chemotherapy with cisplatin regimes, and 35 had radiological residual masses. Twenty-nine of these 35 patients underwent laparotomy and 3 patients had viable tumor, 7 immature teratomas, 3 mature teratoma, and 16 only necrosis or fibrosis. None of the patients with dysgerminoma, embryonal carcinoma, absence of teratoma element in the primary tumor, and radiological residual mass of less than 5 cm had viable tumor, whereas all patients with tumors containing the teratoma component initially had residual tumor, strengthening the case for surgery in patients with immature teratoma and any residual mass (403,404).
The most important prognostic feature of the immature teratoma is the grade of the lesion (2,370). The stage of disease and the extent of tumor at the initiation of treatment have an impact on the curability of the lesion. Overall, the 5-year survival rate for patients with all stages of pure immature teratomas is 70% to 80%, and it is 90% to 95% for patients with surgically staged, stage I lesions (374,377,386).
Endodermal Sinus Tumors Endodermal sinus tumors (EST) are referred to as yolk sac carcinomas because they are derived from the primitive yolk sac (2, 3). These lesions are the third most frequent malignant germ cell tumors of the ovary. ESTs occur in patients with a median age of 16 to 18 years (2,3,405). About one-third of the patients are premenarcheal at the time of diagnosis. Abdominal or pelvic pain is the most frequent initial symptom, occurring in about 75% of patients, whereas an asymptomatic pelvic mass is documented in 10% of patients (343).
The gross appearance of an EST is soft grayish-brown. Cystic areas caused by degeneration or necrosis are present in these rapidly growing lesions. The capsule is intact in most cases.
The EST is unilateral in 100% of cases; thus, biopsy of the opposite ovary is contraindicated.
The association of such lesions with gonadal dysgenesis must be appreciated, and chromosomal analysis should be performed preoperatively in premenarcheal patients (3).