Dynamic Contrast-Enhanced MRI and Its Applications in Various Central Nervous System Diseases

Dynamic contrast-enhanced MRI (DCE-MRI) is a noninvasive imaging technique used to evaluate tissue vascularity/permeability features through consecutive imaging acquisitions after gadolinium-based contrast agent administration. Over the past several decades, techniques and protocols for DCE-MRI have evolved, leading to growing applications of DCE-MRI for different neurological disorders. Although most established applications of DCE-MRI are for studying tumors, an increasing number of studies have been evaluating the use of this technique for neurodegenerative and other miscellaneous diseases. The purpose of this article was to provide an overview of DCE-MRI and its clinical applications in various neurological diseases.

Synchronous Occurrence of Papillary, Follicular, and Medullary Carcinoma in the Same Thyroid Gland / 대한내분비외과학회지

Incidence of thyroid carcinoma has increased dramatically; however, simultaneous occurrence of different tumors in a single thyroid gland is rare and the embryologic or molecular explanations for such cases lack a solid basis. We report on a 67-year-old woman who underwent surgery for cytologically undetermined nodules in the bilateral thyroid glands. Postoperative pathology findings indicated synchronous occurrence of discrete papillary, follicular, and medullary thyroid carcinoma. She has remained disease-free after postoperative radioactive iodine therapy (130 mCi). This is the fifth report on the synchronous occurrence of different tumors in a single thyroid gland worldwide, and the first ever in Asia.

On-site ultrasound-guided localization for impalpable nodal recurrences in papillary thyroid carcinoma patients / 대한외과학회지

PURPOSE: The cervical lymph nodes are the most common sites of locoregional recurrence in patients with papillary thyroid carcinoma (PTC). Accurate tumor localization is important for the successful removal of impalpable recurrences in the cervical lymph nodes. We evaluated the benefits of ultrasound-guided localization (UGL) performed by a single surgeon on site. METHODS: Of 53 PTC patients who underwent reoperation for impalpable nodal recurrences, 32 (group 1) were assessed only using preoperative imaging, while 21 (group 2) were additionally evaluated by on-site UGL performed by the operating surgeon. Postoperative outcomes were compared between the two groups. RESULTS: Operation times were significantly shorter (P < 0.001) and the mean size of the resected lymph nodes were smaller (P = 0.013) for group 2 patients. More lymph nodes were identified and resected in group 1 (3.56 vs. 3.19), but the rate of positive lymph nodes was significantly higher in group 2 (P < 0.001). There were no differences between the two groups in terms of resection success rate, complication rate, and postoperative hospital stay. During a mean follow-up period of 27.6 months, 52 patients (98.1%) showed no evidence of recurrence on routine ultrasound, and serum thyroglobulin concentrations remained < 1 ng/mL in 49 patients (92.5%). CONCLUSION: On-site UGL performed by the operating surgeon is useful for accurate resection of impalpable nodal recurrences in PTC patients.

Tumor Margin Histology Predicts Tumor Aggressiveness in Papillary Thyroid Carcinoma: A Study of 514 Consecutive Patients

Histologic patterns at tumor margins may be related to prognosis in several malignancies. We investigated tumor aggressiveness with respect to tumor margin histology in patients with papillary thyroid carcinoma (PTC). Five hundred fourteen consecutive patients who underwent surgery for primary PTC between January and July 2009 were assigned to two groups, one with an infiltrative pattern (I-type, n = 347) at tumor margins and one with an expanding pattern (E-type, n = 167). Tumor aggressiveness was assessed by analyzing relationships between these patterns and known prognostic factors. The analysis showed that unfavorable prognostic factors such as tumor multiplicity (P = 0.002), extrathyroidal extension (P < 0.001), lateral neck lymph node metastasis (P < 0.001) and advanced TNM stage (P = 0.001) were significantly more prevalent in patients with I-type PTC than in those with the E-type. Central neck node metastases were more prevalent without statistical significance in the I-type patients (P = 0.376). Tumor margin histology was not related to gender or tumor size. These results suggest that histologic patterns at tumor margins predict aggressiveness in PTC.

Traumatic Neuroma following Lateral Neck Lymph Node Dissection in Medullary Thyroid Cancer Patient / 대한내분비외과학회지

A 57-year-old male patient was admitted for evaluation of an enlarged neck lymph node. Previously, the patient had undergone three operations for recurrent medullary thyroid cancer. In preoperative neck ultrasonography, several nodules were identified in right level 3, level 5 and central neck area, which were suspicious for recurrence of thyroid cancer. Selective neck dissection for nodules was performed. Pathologic reports for nodules in right level 3 area were consistent with traumatic neuroma.

Ki-67 and VEGF as Possible Prognostic Factors in Radically-resected Ampulla of Vater Cancer

PURPOSE: Ampulla of Vater cancer has a more favorable prognosis and survival than other malignant periampullary tumors. The pathologic staging of ampulla of Vater carcinoma is a key determinant of the patient's prognosis. However, we have often encountered patients in whom the course of their disease differed substantially from what would be predicted based on their clinical staging, which highlights the need to consider additional predictive factors. We applied an immunohistochemical technique to examine the expression of Ki-67 and VEGF in radicallyresected ampulla of Vater carcinomas, and then compared the status of expression with several clinicopathologic factors. METHODS: Sixty-four patients who underwent curative resection for ampulla of Vater cancer between January 1992 and December 2006 at the Yonsei University College of Medicine were reviewed. The relationships between the expression of molecular markers and clinicopathologic factors were determined. RESULTS: There was no relationship between the clinicopathologic characteristics and the expression of molecular markers in patients with ampulla of Vater cancer. Among the clinicopathologic characteristics, lymph node metastasis was identified as an independent factor of survival after curative resection for ampulla of Vater carcinoma. CONCLUSION: Measurement of Ki-67 and VEGF in patients with ampulla of Vater carcinoma may have an important role in identifying the poor prognostic group.

Left Colonic Antegrade Continence Enema: Experience Gained from 19 Cases

PURPOSE: As problem have developed with the right colonic antegrade enema procedure (Malone's procedure/Monti's retubularized ileocolostomy), left colonic antegrade continence enema (LACE) procedure, in which retubularized ileum or sigmoid colon is anastomosed into the sigmoid colon, has gained popularity. The aim of the study was to describe our experience with the LACE procedure. METHODS: We retrospectively reviewed 19 LACE procedures that were performed at the Yonsei University Colllege of Medicine Hospital (Seoul, Korea) from March 2001 to March 2005. RESULTS: Male-to-female ratio was 11 : 8, with median age of 10 years (range, 3~34 years). Most common diagnosis was meningomyelocele (78.9%, 15/19). The median total follow-up period was 23 months (range, 3~37 months); median antegrade continence enema volume used was 600 ml (range, 250~1,500 ml); and median transit time was 30 minutes (range, 15~60 minutes). Patients performed antegrade continence enema with an average of once every 2 days (range, 0.3~3 days). Social continence was achieved in 14 patients (73.7%). Regurgitation of fecal material through stoma was not reported at all in 17 patients (89.5%). CONCLUSION: We recommend LACE as the procedure of choice for patients with congenital malformation or any other condition predisposing to fecal incontinence or constipation intractable to conventional treatment.

Spine Metastases as the Initial Sign of Differentiated Thyroid Carcinoma: Two Case Reports / 대한내분비외과학회지

Bone metastases as the first manifestation of thyroid carcinoma are extremely rare. Interestingly, evaluation at appropriate initials and proper treatment will lead to satisfactory long-term survival. We report here on two such cases; the patients presented with back pain and fine needle aspiration cytology of spine lesion revealed a metastatic carcinoma. A wide excision of the bone lesion was carried out and the histopathology was consistent with features of metastatic carcinoma of the thyroid. The management of thyroid carcinoma and the subsequent bone metastases is reviewed and the controversial points are highlighted.