Principal investigator left the investigational center and nobody took over.

Thyroid carcinoma on struma ovarii (TCSO) is a rare ovarian tumor, derivate from monodermic teratomas. It represents about 0.01% of overall ovarian tumours, and 5 to 10% of struma ovarii. The diagnosis is histologic and retrospective after pelvic surgery. Because of its rarity, the treatment of TCSO is not consensual and should be validated in multidisciplinary team involved in rare ovarian carcinoma. TCSO should be taken care of as a thyroid carcinoma, in case of relapse, with systemic treatment, as tyrosine kinase inhibitor (TKI), without any clinical trial proving this benefit. Indeed, molecular profiles and genomic expression is unknown, because of studies with few patients (less than 10) contrary to thyroid carcinomas with the TCGA genomic classification. The study purposes are the outcome of the patients after the first treatment and the comparison of the genomic profil in next generation sequencing (NGS) with TCGA thyroid carcinoma profile. Thus, the treatment could be tailored, confirming the same therapy as in thyroid carcinoma.

This is a retrospective cohort with collection of tissues samples (FFPE or frozen), including female patients >18-year-old treated in French between 2009 and 2016 for a thyroid carcinoma on struma ovarii. Clinical data and tissues will be centralized for assessment. One of the endpoint is the description of the population (such as baseline clinical and pathologist characteristics, first treatment, survival, treatment relapse) ; the other endpoint is the comparison between the genomic profile of the tumor tissues obtained in NGS and those of the thyroid carcinomas obtained from the TCGA.

Inclusion Criteria:

• Alive patients,
• Age > 18 years,
• Treatment in France for a TCSO, proven by an histologic diagnosis and registered in the " rare malignant gynecologic tumors " network.

Exclusion Criteria:

- Patient lost to follow up.

French women older than 18 years old with a TCSO registered in the French " Rare malignant gynecologic tumors " network from 2007 to 2017.