Metastatic squamous cell carcinoma arising from mature teratoma of the ovary: Description of multi-modality treatment including incorporation of adjuvant immunotherapy and maintenance PARP inhibitor therapy

Mature cystic teratomas (MCTs) are relatively common ovarian germ cell tumors that occur in 1.2–14.2 patients per 100,000 per year and are largely considered to be benign, although 0.17–2 % of MCTs demonstrate malignant transformation (Hackethal et al., 2008). About 80 % of those are characterized as squamous cell carcinoma (SCC) arising from the ectoderm (Gadducci et al., 2019). While International Federation of Gynecology and Obstetrician (FIGO) staging correlates with prognosis in the cases reported, a difference has been described between stage I and more advanced including stage II, III, and IV, with only small numbers of reported cases in the stage IV category (Hackethal et al., 2008, Chen et al., 2008). There is a dearth of information regarding optimal approach and therapy options for patients with SCC arising from MCT, particularly at more advanced stages. Previous reports demonstrate evidence for survival benefit with cytoreductive surgery in combination with carboplatin and paclitaxel (Hackethal et al., 2008). Additionally, recent case reports describe the use of immunotherapy and other targeted therapies with variable efficacy (Wu et al., 2021) (Martel et al., 2023) (Tamura et al., 2023).

Here we add to the existing literature with a report describing the use of multimodality therapy in the treatment of a SCC arising within MCT, in order to further expand options for fertility sparing, timing of treatment, and maintenance therapy, in the setting of advanced disease.

Esther Peluso: Writing – review & editing, Writing – original draft, Resources, Data curation, Conceptualization. Wesleigh Fowler Edwards: Writing – review & editing, Conceptualization. Jo Marie Tran Janco: Writing – review & editing, Resources, Data curation, Conceptualization.