Table 1.

Summary table of thyroid carcinoma arising in struma ovarii

Etiology	Unknown
Incidence	Struma ovarii: 5% of all ovarian teratomas
	Thyroid-carcinoma arising in struma ovarii: 5–10% Papillary carcinoma - 70% (classical subtype - 44%; follicular variant subtype -26%) Follicular carcinoma - 30%
Gender ratio	Women
Age predilection	4th–6th decade
Risk factors	Lesions> 16cm; Strumosis
Treatment	Unilateral or bilateral salpingo-oophorectomy (depending on age) + total thyroidectomy
Prognosis	Still unknown
Findings on imaging	US - Mixed solid and cystic mass, exhibiting abundant and low resistance flow within the central solid component on color Doppler imaging CT - Multiloculated cystic mass presenting fluid with variable density between locules; Calcifications may be identified MR - Multiloculated cystic mass presenting fluid with variable signal intensity (“stained glass appearance”) among locules and a solid component, which usually displays avid gadolinium enhancement. The fatty component is not a common feature, except when it occurs in association with mature cystic teratoma. Ascites can be present. NOTE: The diagnosis of malignant thyroid tissue is based on microscopic findings.