Immature ovarian teratoma in a 20-year-old woman: A case report

Abstract

Immature ovarian teratomas are a rare subtype of germ cell tumours characterized by the presence of embryonic elements, particularly primitive neuroepithelium, and they typically affect young women. We report the case of a 20-year-old woman who presented with a growing abdominal mass that turned out to be a grade II immature teratoma after adnexectomy. This article reviews the clinical presentation, imaging features, and some of the main problems that arise in the management of immature ovarian teratomas.

Background

Approximately 90% ovarian malignancies are epithelial cell-type tumors composed of many subtypes, each with unique molecular alterations, clinical characteristics, and responses to treatment. ¹ The remaining 10% are non-epithelial ovarian malignancies, and consist mainly of germ cell tumors, sex cord-stromal tumors, and a few rare tumors, such as small cell carcinomas. Germ cell tumors are the most prevalent ovarian neoplasm in women up to the age of 30 years and most patients (60–70%) are diagnosed with early-stage disease. ¹ An immature ovarian teratoma is a rare type of germ cell tumor that can occur in either a pure form or, in association with other non-teratomatous germ cell tumor components; they represent <1% of all ovarian cancer cases ² Typically, immature ovarian teratomas affect young women in the first two decades of life, with peak occurrence between ages of 16 and 20 years, and specific risk factors include, delayed puberty, primary amenorrhea, and racial and ethnic disparities. ³

Histologically, an immature ovarian teratoma is differentiated from a mature teratoma by the presence of embryonic elements, particularly primitive neuroepithelium. These tumours are histologically graded from I to III based on the quantity of immature neural tissue; grade I tumors contain rare immature tissue, whereas grade III tumors consist mainly of embryonal tissue with high mitotic activity. This grading distinction has significant therapeutic and prognostic implications.^4–6

We describe here, the case of a 20-year-old woman who presented with a growing abdominal mass that turned out to be a grade II immature teratoma.

Case report

Our patient was a 20-year-old unmarried, nulligravida woman, without any significant medical history, who sought medical attention due to persistent chronic abdominopelvic pain. The pain was effectively managed with analgesics, and there were no concomitant urinary symptoms. The patient reported a recent weight loss of 15 kg over a three-month period and presented with a general sense of malaise, though she had no fever.

Upon initial examination, the patient was fully conscious, hemodynamically stable, and exhibited normal respiratory function, with a blood pressure of 120/70 mmHg. Gynecological evaluation showed a painful, sizable abdominopelvic mass, palpable in the hypogastric region, extending beyond the umbilicus. Notably, vaginal and speculum examinations were deferred as the patient reported being a virgin. To investigate the source of the abdominopelvic pain further and examine the palpable mass, a transabdominal pelvic ultrasound was performed (Figure 1). The ultrasound results showed a vascularized abdominopelvic mass characterized by both solid and cystic components. Subsequent laboratory assessments included blood tests for tumour markers (e.g., carbohydrate antigen 125 (CA125), levels of human chorionic gonadotropin (HCG), and alpha-fetoprotein (AFP), all of which yielded negative results. To gain a comprehensive view of the mass, a thoraco-abdominopelvic computed tomography scan (TAP CT) was conducted. The scan showed a solid-cystic mass located in the right ovary. Notably, this mass displayed fatty and calcified components, strongly suggestive of an immature teratoma. Given these findings, the patient underwent a right adnexectomy with multiple biopsies to confirm the nature of the mass (Figure 2). An anatomopathological examination of the biopsies corroborated the presence of a grade II immature teratoma (Figure 3).

Figure 1.

Ultrasound of the abdomen showing the mass characteristics. Results showed a vascularized abdominopelvic mass characterized by both solid and cystic components.

Figure 2.

Macroscopic aspect of the teratoma.

Figure 3.

Photomicrographs of haematoxylin-and-eosin (H&E)-stained tissue sections showing various types of tissues found within the cyst: (a), foci of salivary serous-mucous acini; (b), bone; (c and d), squamous epithelium; (e), numerous foci of the immature neuroepithelial component (black arrow).

The patient faced a challenging decision regarding her treatment options. Although radical interventions were discussed, the patient expressed a strong desire to preserve her fertility. Consequently, chemotherapy was proposed as a more conservative approach. The patient responded positively to the prescribed chemotherapy regimen, and her condition was carefully monitored throughout her treatment course.

The reporting of this study conforms to CARE guidelines. ⁷ Written informed consent was obtained from the patient to publish her anonymised data. The case report did not require ethics committee approval.

Discussion

Clinically, immature ovarian teratomas often present as painful, unilateral, and rapidly enlarging abdominal masses, with an average diameter of approximately 18 cm. Occasionally, they are discovered incidentally following acute abdominal pain caused by rupture or torsion.^4,5 Elevated levels of serum markers, such as AFP, CA 125, and CA 19-9 may be associated with these tumours. Indeed, these markers have shown specificity and sensitivity in clinical use, and have aided disease progression monitoring.^4,8,9

Currently, the standard of care, as per The National Comprehensive Cancer Network (NCCN) guidelines, recommend fertility-sparing surgery, typically involving unilateral adnexectomy, with peritoneal staging. Chemotherapy is recommended for all cases beyond stage I and grade I, with stage I grade I tumors often considered curable by surgery alone. ¹⁰ However, one study suggested that patients with advanced-stage immature ovarian teratomas may also benefit from fertility-sparing surgery; the authors found no difference in recurrence between cytoreductive and radical surgery. ¹¹

The debate arises when the immature ovarian teratoma diagnosis is made postoperatively following histological examination without a prior peritoneal biopsy. In grade I tumors, a second-look surgery may be considered if peritoneal glial implants are detected, indicating the need for chemotherapy. However, in grades II and III, a second surgical intervention may not be warranted as chemotherapy is indicated irrespective of the presence of peritoneal implants. ¹⁰ Although several studies have demonstrated that peritoneal, surgical staging reduces the recurrence rate, it does not necessarily enhance overall survival. Therefore, there is limited support for the ‘second-look’ staging surgery. Instead, surveillance is recommended for incorrectly staged or unstaged patients, and relapsed patients can typically be managed with chemotherapy.^9,12–14 In our case, we opted for chemotherapy without pursuing second surgery, and followed a fertility-preserving approach.

Reported rates of lymph node and omentum metastasis are generally low, particularly in early-stage malignant ovarian germ cell tumors (e.g., immature ovarian teratomas) that are clinically apparent.^15,16 Consequently, the European Society for Medical Oncology does not include lymphadenectomy and omentectomy as part of the initial standard surgical approach.^17,18 Importantly, research indicates that fludeoxyglucose F18 (FDG) positron emission tomography (PET)/CT scans can detect lymph node metastasis and identify sites for pathological examination, and can assist in accurate tumor staging. ¹⁹

Post-operative follow-up is pivotal in managing an immature ovarian teratoma, especially in cases with inadequate staging. A minimum follow-up period of 10 years is recommended, involving physical examinations and serum marker monitoring. ²⁰ One study using data from The National Cancer Database (NCDB) reported overall survival rates of near 100%, although factors such as late age at diagnosis, advanced stage, and high-grade histology were associated with increased mortality. ²¹