Thyroid Pathology (thyroid + pathology)

Distribution by Scientific Domains


Selected Abstracts


Vascular endothelial growth factor (VEGF), VEGF receptors expression and microvascular density in benign and malignant thyroid diseases

INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2007
Ala'eddin Jebreel
Summary Angiogenesis is critical for the growth and metastatic spread of tumours. Vascular endothelial growth factor (VEGF) is the most potent inducer of neovasculature, and its increased expression has been related to a worse clinical outcome in many diseases. The purpose of this study was to evaluate the relation between VEGF, its receptors (VEGFR-1 and VEGFR-2) and microvessel density (MVD) in thyroid diseases. Immunostaining for VEGF and VEGF receptors was performed in 66 specimens of thyroid tissue, comprising 17 multinodular goitre (MNG), 14 Graves' disease, 10 follicular adenoma, 8 Hashimoto's thyroiditis, 7 papillary carcinoma and 10 normal thyroid specimens. Thyrocyte positivity for VEGF and VEGF receptors was scored 0,3. Immunohistochemistry for CD31, and CD34 on the same sections was performed to evaluate MVD. Immunohistochemical staining of VEGF in thyrocytes was positive in 92% of all the thyroid tissues studied. Using an immunostaining intensity cut off of 2, increased thyrocyte staining was seen in follicular adenoma specimens, MNG and normal thyroids compared with Hashimoto's thyroiditis and Graves' disease (P < 0.05). Similarly, VEGF thyrocyte expression in Graves' disease was less than other pathologies (P < 0.05). VEGFR-1 expression and the average MVD score did not differ between the different thyroid pathologies. VEGF expression was lower in autoimmune pathologies compared to autonomous growth processes. Conversely, both VEGFR-1 and VEGFR-2 were widely expressed in benign and neoplastic thyroid disease, suggesting that the up-regulation of VEGF and not its receptors occurs as tissue becomes autonomous. There was no clear relationship between MVD measurement and thyroid pathology. [source]


Thyroid Imaging in the Dog: Current Status and Future Directions

JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 4 2007
O. Taeymans
This review describes the advantages and disadvantages of radiography, ultrasonography, and nuclear medicine in the 2 most frequent thyroid pathologies of the dog: acquired primary hypothyroidism and thyroid neoplasia. Ultrasonography and scintigraphy remain the 2 most indicated imaging modalities for these thyroid abnormalities. However, as in human medicine, computed tomography and magnetic resonance imaging also have potential indications. This is especially the case in the evaluation of the extent, local invasiveness, and local or distant metastases of thyroid neoplasia. Based on experience with different imaging modalities in people, we suggest future directions in the imaging of the canine thyroid gland. [source]


Vascular endothelial growth factor (VEGF), VEGF receptors expression and microvascular density in benign and malignant thyroid diseases

INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2007
Ala'eddin Jebreel
Summary Angiogenesis is critical for the growth and metastatic spread of tumours. Vascular endothelial growth factor (VEGF) is the most potent inducer of neovasculature, and its increased expression has been related to a worse clinical outcome in many diseases. The purpose of this study was to evaluate the relation between VEGF, its receptors (VEGFR-1 and VEGFR-2) and microvessel density (MVD) in thyroid diseases. Immunostaining for VEGF and VEGF receptors was performed in 66 specimens of thyroid tissue, comprising 17 multinodular goitre (MNG), 14 Graves' disease, 10 follicular adenoma, 8 Hashimoto's thyroiditis, 7 papillary carcinoma and 10 normal thyroid specimens. Thyrocyte positivity for VEGF and VEGF receptors was scored 0,3. Immunohistochemistry for CD31, and CD34 on the same sections was performed to evaluate MVD. Immunohistochemical staining of VEGF in thyrocytes was positive in 92% of all the thyroid tissues studied. Using an immunostaining intensity cut off of 2, increased thyrocyte staining was seen in follicular adenoma specimens, MNG and normal thyroids compared with Hashimoto's thyroiditis and Graves' disease (P < 0.05). Similarly, VEGF thyrocyte expression in Graves' disease was less than other pathologies (P < 0.05). VEGFR-1 expression and the average MVD score did not differ between the different thyroid pathologies. VEGF expression was lower in autoimmune pathologies compared to autonomous growth processes. Conversely, both VEGFR-1 and VEGFR-2 were widely expressed in benign and neoplastic thyroid disease, suggesting that the up-regulation of VEGF and not its receptors occurs as tissue becomes autonomous. There was no clear relationship between MVD measurement and thyroid pathology. [source]


Ultrasonography: Highly Accuracy Technique for Preoperative Localization of Parathyroid Adenoma,

THE LARYNGOSCOPE, Issue 9 2008
Bassam Abboud MD
Abstract Objectives/Hypothesis: This study evaluates the accuracy of ultrasonography in guided unilateral parathyroidectomy to treat primary hyperparathyroidism. Study Design: Retrospective study. Methods: Two hundred fifty-three patients with primary hyperparathyroidism underwent preoperative ultrasonography. Two groups were defined. Group 1 included the patients in whom the preoperative cervical ultrasound localized one abnormal parathyroid gland; these patients underwent unilateral surgical exploration of the neck under local anesthesia. Group 2 included the patients who had a bilateral neck exploration under general anesthesia when the preoperative examination was equivocal or failed to localize the lesion, when concomitant thyroid pathology indicated thyroidectomy, and when justified by the surgical findings. Results: Sensitivity and positive predictive value of ultrasonography in detecting abnormal parathyroid gland were 96% and 98%, respectively. Cervical ultrasound correctly identified, 96% and 85% of abnormal glands in groups 1 and 2, respectively. The presence of thyroid nodular disease did not affect ultrasonographic accuracy. Sonographic examination decreased the operative time of parathyroidectomy to an average of 15 minutes. Mediastinal and retroesophageal localizations of abnormal parathyroid gland adversely affected the accuracy of the ultrasound. No cervical hematoma was noted. Transient recurrent laryngeal nerve palsy occurred in four patients. Twenty-three patients required postoperative calcium supplementation for 2 to 4 months, and all were normocalcemic at follow-up. Conclusions: Cervical ultrasound is a reliable preoperative exploration allowing parathyroidectomy via unilateral approach under local anesthesia. [source]


A Safe and Cost-Effective Short Hospital Stay Protocol to Identify Patients at Low Risk for the Development of Significant Hypocalcemia After Total Thyroidectomy

THE LARYNGOSCOPE, Issue 6 2006
Zayna S. Nahas BS
Abstract Objective: The objective of this retrospective chart review was to determine if serial postoperative serum calcium levels early after total thyroidectomy can be used to develop an algorithm that identifies patients who are unlikely to develop significant hypocalcemia and can be safely discharged within 24 hours after surgery. Methods: Records of 135 consecutive patients who underwent total/completion thyroidectomy and were operated on by the senior author from 2001 to 2005 have been reviewed. For the entire study group, reports of the early postoperative serum calcium levels (6 hours and 12 hours postoperatively), final thyroid pathology, preoperative examination, inpatient course, and postoperative follow up were reviewed. An endocrine medicine consultation was obtained for all patients while in the hospital after surgery. For patients who developed significant hypocalcemia, reports of their management and the need for readmission or permanent medications for hypoparathyroidism were reviewed. According to the change in serum calcium levels between 6 hours and 12 hours postoperatively, patients were divided into two groups: 1) positive slope (increasing) and 2) nonpositive (nonchanging/decreasing). Results: All patients with a positive slope (50/50) did not develop significant hypocalcemia in contrast to only 59 of 85 patients (69.4%) with a nonpositive slope (P < .001, positive predictive value of positive slope in predicting freedom from significant hypocalcemia = 100%, 95% confidence interval = 92.9,100). In the nonpositive slope group, 61 patients had a serum calcium level ,8 mg/dL at 12 hours postoperatively (,0.5 mg/dL below the low end of normal), and 53 (87%) of these patients remained free of significant hypocalcemia in contrast to only 6 (25%) of 24 patients with serum calcium level <8 mg/dL at 12 hours postoperatively (sensitivity = 90%, positive predictive value = 87%). In addition, of the eight patients who developed significant hypocalcemia in the nonpositive slope group with a serum calcium level ,8 mg/dL at 12 hours postoperatively, 7 (88%) patients developed the signs and symptoms during the first 24 hours after total thyroidectomy. Readmission and permanent need for calcium supplementation happened in two patients, respectively, all with serum calcium levels <8 mg/dL at 12 hours after total thyroidectomy. The compressive and/or symptomatic large multinodular goiter as an indication for thyroidectomy was associated with developing significant hypocalcemia (P < .05). There was no statistically significant correlation between the development of significant hypocalcemia and gender, age, thyroid pathology other than goiter, or neck dissection. Conclusion: Patients with a positive serum calcium slope (t = 6 and 12 hours) after total thyroidectomy are safe to discharge within 24 hours after surgery with patient education with or without calcium supplementation. In addition, patients with a nonpositive slope and a serum calcium level ,8 mg/dL at 12 hours postoperatively (,0.5 mg/dL below the low end of normal) are unlikely to develop significant hypocalcemia, especially beyond 24 hours postoperatively, and therefore can be safely discharged within 24 hours after total thyroidectomy with patient education and oral calcium supplementation. Our management algorithm identifies those patients at low risk of developing significant hypocalcemia early in the postoperative course after total thyroidectomy to allow for a short hospital stay and safe discharge. [source]


Predictive factors for recurrent laryngeal nerve palsy and hypoparathyroidism after thyroid surgery

CLINICAL OTOLARYNGOLOGY, Issue 1 2007
Y. Erbil
Objectives:, To evaluate the incidence and risk factors of recurrent laryngeal nerve palsy and hypoparathyroidism following thyroidectomy. Design:, Retrospective case,control study. Setting:, Tertiary clinic. Participants:, From September 1990 to September 2005, 3250 consecutive patients who had a thyroidectomy for treatment of various thyroid diseases. Main outcome measures:, The rates of nerve palsy and hypoparathyroidism were evaluated based on thyroid pathology, the choice of operative procedure, whether the nerve was identified, and the experience of the surgeon. Results:, Overall, the rate of nerve palsy was 1.8% and that of hypoparathyroidism was 6.6%. On univariate analysis the rates of complications were siginificantly higher in the patients who had an extended thyroidectomy, identification of the recurrent laryngeal nerve during surgery, repeat surgery and patients older than 50 years of age. Complications were no commoner in operations performed by trainees under supervision than experienced surgeons. On multivariate analysis extended thyroidectomy had a 12 fold (95% CI 1.7, 92) increased risk of nerve palsy. Repeat surgery had a 3 fold (95% CI 2.1, 4.7) increased risk of postoperative hypoparathyroidism. Conclusion:, Extentended thyroidectomy and repeat surgery had a significant effect on the incidence of recurrent laryngeal nerve palsy and postoperative hyperparathyroidism respectively following thyroid surgery. [source]