Introduction: Papillary carcinoma arising from thyroid tissue in mature cysticteratoma (MCT) of the ovary is extremely rare, and it is not easy to diagnose preoperatively. No clinical, no radiological, no biological signs are specific to malignant transformation. Case presentation: A 51-year-old woman had a left ovarian tumor measuring approximately 18 cm diameter with malignant transformation of a mature cysticteratoma, who was diagnosed postoperatively with follicular variant of papillary thyroid carcinoma. A laparoscopic hysterectomy and left salpingo-oophorectomy were performed. During surgery, there were no signs of invasion or metastasis. Conclusion: Consideration should be given to thyroidectomy followed by total-body scanning and serum studies for foci of thyroid carcinoma and adjuvant therapy with thyroidectomy and radio ablation if residual disease is identified.
Mature cysticteratoma commonly referred to as a dermoidcyst of the ovary. It is the most common type of ovarian teratoma and germ cell neoplasm comprising 10% - 20% of ovarian tumors in the female reproductive period [
The most common malignant tumor in mature cysticteratomas is squamous cell carcinoma, whereas, papillary thyroidcarcinoma is extremely rare. Malignant transformation is rarely diagnosed preoperatively, due to its rarity [
A 51-year-old woman, with no significant medical history, was admitted in gynecology with a pelvic pain associated with signs of digestive compression occurring in a context of poorgeneral condition.
Her physical examination revealed a abdominal pelvic mass beyond the umbilicus, hard consistency, movable relative to both superficial and deep planes.
Ultrasound of the abdomen revealed a large multilobular mixed cystic and solid abdomino-pelvic mass 18 × 15 cm, containing hyperechogenic areas, calcifications werenoted, densely adherent to the intestinal and uterine wall with moderateascitis.
The intraoperative exploration found a large tumor appeared to have originated from the left ovary and adherent to hail. A hysterectomy and left salpingo-oophorectomy with resection of the small intestine were performed.
Macroscopic appearance of the lesion resembled a dermoidcyst, color yellowish, seat alterations and necrotic hemorrhagic and contained cystic microcavities colloid content.
Histopathologic evaluation of the lesion demonstrated a follicular variant papillary thyroidcarcinoma in a mature cysticteratoma and surrounded by normal ovarian tissue with a intact capsule.
Microscopic examination revealed a mature cystic teratoma with multiple focus of follicular variant papillary thyroid cancer (
The diagnosis was of Follicular variant of papillary thyroid carcinoma arising from a Mature cysticteratoma.
Thyroid ultrasonography was necessary to eliminate any primary thyroid malignancy and serum thyroid function tests were normal.
Tyroidectomy was performed and pathological examination of the thyroid gland was normal. The patient was
under surveillance for 6 months, with no evidence of recurrence.
Mature cysticteratoma of the ovary is the most common germ cell tumour accounting for a third of all ovarian tumours and ninety-five per cent of these cases are benign. Usually unilateral, it is by definition composed of well-differentiated derivates (like teeth, hair, bone and thyroid tissue) which originate from all three germ cell layers and is most frequently diagnosed during the female reproductive period [
A malignant transformation of the mature cysticteratoma is an uncommon complication and occurs in 1% -
2% of cases, most frequently in postmenopausal women [
In 1957, Peterson reviewed 229 cases of malignant transformation of mature cysticteratomas [
The presence of thyroid tissue in the ovaries was first described by Von Kahlden in 1895 [
Malignant transformation of thyroid tissue in mature cysticteratoma can be classified Histopathologically into three types [
In our case, a follicular variant papillarythyroid carcinoma was found. It is a teratoma with a thyroid tissue, where we found a area with typicalhistological characteristics of a follicular variant papillary thyroidcarcinoma and positive TTF1, cytokeratine 19, thyroglobulin on immunohistochemical analysis.
The survival outcome of patients with malignant transformation of the ovarian mature cysticteratomas is dependent on the stage. These tumors arising from ovarian teratomas can occasionally present with locally invasive disease, or with distant metastases, and may be associated with recurrences in some patients. In the present case, a lesion was found on the left ovary, with ascite and adherent to the intestinal without rupture or tumor dissemination.
Conservative treatment is often offered to younger patients who wished to retain their fertility and it consists of unilateral salpingo-oophorectomy or cystectomy without adjuvant therapy. Conservation of ovarian tissue on the affected side is acceptable [
Thyroidectomy was necessary not only to confirm normal thyroid, but also to facilitate nuclear medicine imaging, so that radioactive iodine uptake would occur mainly in metastatic thyroid tissue. Later this would also have potentiated therapy if metastases were detected [
Serial measurement of serumthyroglobulinis a sensitive and it should be used for long-term follow-up, up to 10 years to detect metastasis or tumor recurrence [
The optimal treatment for malignant transformation of mature cysticteratoma is uncertain because of the rarity of the disease [
Early detectionis important for long-term survival. Old age, large tumor size, and solid portion in mature cysticteratoma seem to predict the malignant transformation of mature cysticteratoma [
Due to the paucity of cases published, it is difficult to predict the natural progression of this disease, its management and the long-term prognosis.