Aberrant migration of thymic tissue occurs as an ectopic thymus in the mediastinum, base of skull, tracheal bifurcation, and cervical region. A recent review of the literature by Nowak et al. showed over 70 reported cases of aberrant thymus or thymic cyst in patients who presented with primary neck masses. Authors experienced a case of ectopic cervical thymus and reviewed the literature. A one-year-old boy with left neck swelling which had been noticed since one month of age visited out patient clinic. Ultrasonography showed a well-defined cystic mass containing homogeneous, low-echogenic content locating in the lateral aspect of the left carotid sheath. Operation was performed under the impression of branchial cleft cyst. At surgery, a multiseptated, well-encapsulated, brownish and doughy mass which was extending into the vicinity of the carotid bifurcation with sland stalk-like portion ending between the hypoglossal nerve and external carotid artery was excised completely. The cut-surface showed homogenous solid mass, and on frozen section the tissue revealed a normal thymic histology. Postoperative ultrasonography showed bilateral thymus in the superior mediastinum. The patient has no immunologic problem and is doing well now.

We reviewed 45 cases of ovarian tUmors treated at Seoul National University Children's Hospital from 1983 to 1993. Forty-five patients were operated upon for 52 ovarian tumors. The most common pathologic diagnosis was mature teratoma. The next were functional cyst, the tumors of epithelial cell origin, and those of stromal origin in order of frequency. Six patients(13%) had malignant tumor. There were one malignant teratoma, two dysgerminomas, one endodermal sinus tumor, and two granulosa cell tumors. Four cases were diagnosed as torsion of ovarian cyst preoperatively, and emergency exploratory laparotomy were performed. There were three cases of ovarian tumors associated with precocious puberty. The most widely used diagnostic tool was ultrasonography.

In the treatment of these 45 patients, unilateral oophorectomy was done in 38 cases, unilateral oophorectomy with wedge resection of contralateral ovary was done in 5 cases, unilateral oophorectomy with contralateral simple cystectomy was done in one case and total abdominal hysterectomy with bilateral salpingooophorectomy was done in one case. Of the six cases of malignancy, five patients are alive 2 to 6 years after operation and one case was lost to be followed up.