Ovarian mature cystic teratoma with malignant transformation into squamous-cell carcinoma:report of two cases and review of literature

QI Wenjuan; XU Junqing

doi:10.3969/j.issn.1007-8096.2025.08.017

Abstract：Objective To explore the clinicopathological features,diagnosis,differential diagnosis,treatment and prognosis of ovarian mature cystic teratoma deteriorated into squamous-cell carcinoma,so as to deepen the cognition of deterioration of mature cystic teratoma.Methods The clinical data,imaging features,pathological features and treatment prognosis of 2 patients with ovarian mature cystic teratoma deteriorated into squamous-cell carcinoma were retrospectively analyzed.HE staining and immunohistochemical staining of EnVision were used,and relevant literatures were reviewed.Results Two patients with mature cystic teratoma of ovary turned into squamous cell carcinoma,all of them happened in the left ovary,with a mean age of 54 years,1 patient was in reproductive age and 1 patient in menopause.The clinical manifestations were pelvic mass,abdominal distension and falling feeling.Grossly,the maximum diameter of the mass was 14.5～15.5 cm,and all of them were and cystic and solid.The section of the solid area was grayish yellow,grayish white,nodular and hard in texture.Cystic area contained hair,grease,bone and greasy.Microscopicall Teratoma components such as skin appendages,cartilage,fat and squamous epithelium were seen in tumor tissues,as well as a large number of squamous cell carcinoma components.The tumor cells were distributed in nests,with invasive growth accompanied by extensive necrosis,obvious cell atypia,rough nuclear chromatin,obvious nucleoli,and brisk mitoticfigures.The differentiation characteristics of squamous epithelium such as keratinization bead,intracellular keratinization and intercellular bridge were noted.Immunophenotypically,malignant cells were positive for p40,p63 and CK5/6;ki-67 was 40％～80％.One patient underwent surgery of total hysterectomy,bilateral adnexectomy and partial greater omentum resection who was in clinical stage Ⅰa,followed by 4 cycles of chemotherapy.Another patient underwent surgery of bilateral adnexectomy,resection of pelvic floor lesions and mesenteric lesions,followed by 6 cycles of chemotherapy.All patients were followed up for 12 months,and no recurrence or metastasis was found.Conclusion Mature cystic teratoma of ovary is a common benign tumor,but malignant squamous cell carcinoma is rare,and the clinical symptoms are not specific,preoperative diagnosis is difficult,and the diagnosis depends on histopathology and immunohistochemical detection.Therefore,pathological sampling should be careful and comprehensive to avoid missing malignant components.