Urokinase plasminogen activator and its inhibitor type-1 as prognostic factors in differentiated thyroid carcinoma patients.

OBJECTIVE: To investigate the prognostic value of urokinase-type plasminogen activator (uPA) and its inhibitor, type-1 plasminogen activator inhibitor (PAI-1), in differentiated thyroid cancer. STUDY DESIGN: Prospective cohort study. SETTING: University hospital. SUBJECTS AND METHODS: Cytosolic concentrations of uPA and PAI-1 were determined in 105 patients with differentiated thyroid carcinoma and normal matched tissues using an enzyme-linked immunoassay (ELISA). RESULTS: Both uPA and PAI-1 concentrations were significantly higher in differentiated thyroid tumors (uPA = 0.509 ± 0.767 and PAI-1 = 6.337 ± 6.415 ng/mg) compared to normal tissues (uPA = 0.237 ± 0.051, P < .001; PAI-1 = 2.368 ± 0.418 ng/mg, P < .001). uPA and PAI-1 were significantly higher if extrathyroidal invasion (uPA, P = .015; PAI-1, P < .001) or distant metastasis (PAI-1 P < .001) was present, as well as in tumors whose size exceeded 1 cm in diameter (uPA, P = .002; PAI-1, P = .001). Survival analysis revealed the significant impact of both uPA and PAI-1 on progression-free survival (PFS) (82.22 vs 49.478 months for patients with low and high uPA, respectively, P < .001; 87.068 vs 44.964 months for patients with low and high PAI-1, respectively, P < .001). Univariate analysis showed that gender, tumor size, tumor grade, extrathyroid invasion, local lymph node involvement, distant metastasis, uPA, and PAI-1 were significant predictors of PFS. However, multivariate analysis identified only distant metastasis and tumor tissue uPA and PAI-1 as independent prognostic factors. CONCLUSION: These findings indicate that high uPA and PAI-1 levels represent independent unfavorable prognostic factors in patients with differentiated thyroid carcinoma.

Thyroid remnant ablation in patients with papillary cancer: a comparison of low, moderate, and high activities of radioiodine.

OBJECTIVE: The consensus about optimal activities of I-131 for thyroid remnant ablation has not yet been achieved. The aim of this study was to compare ablation rates obtained with different I-131 activities. PATIENTS AND METHODS: The study included 466 patients divided into four groups according to I-131 activities given after total thyroidectomy for papillary thyroid cancer: group A [168 patients who received 888 MBq (24 mCi)], group B [125 patients who received 1480 MBq (40 mCi)], group C [65 patients who received 1850 MBq (50 mCi)], and group D [108 patients who received 4440 MBq (120 mCi)]. Ablation outcome was assessed by whole-body scan in hypothyroid state 6-9 months after ablation and finally 18-21 months after the treatment. RESULTS: The rate of successful ablation was similar in the group of patients who received 24 and 40 mCi (75 and 71.2%, respectively). The higher rate of ablation was achieved in the groups treated with 50 and 120 mCi of radioiodine (87.69 and 90.74%, respectively). The ablation rates at the first follow-up examinations (59.5, 67.2, 73.9, 80.6%) were lower than at second control study (75.0, 71.2, 87.7, 90.7%) in all groups. Time required for thyroid remnant ablation seems to be >or=18 months. CONCLUSION: Our study indicates that activity of 50 mCi seems to be optimal to achieve a successful ablation rate (approximately 90%). Low I-131 activities are acceptable for lower risk patients because of satisfactory ablation rate (>70%), lower expense, and minimal radiation burden to patients as well as lower radiation exposure to clinical staff. The ablative use of high activities seems neither justified nor optimized.

Ultrasonographic differentiation of benign from malignant neck lymphadenopathy in thyroid cancer.

OBJECTIVE: The aim of this study was to determine whether ultrasonography itself was able to distinguish benign from malignant lymphadenopathy in patients with thyroid cancer. METHODS: We evaluated lymph nodes in a group of patients with thyroid cancer. Nodes were detected and measured by ultrasonography, and their shape, echogenicity, size, and location were noted. Ultrasonographically guided fine-needle aspiration biopsy (FNAB) was performed, and smears were analyzed cytologically. RESULTS: Ultrasonographically guided FNAB was performed in 578 neck nodes in a group of 631 patients with thyroid cancer. In most cases, metastases had a round shape and various echo structures, with a predomination of hypoechoic nodes without a hilum. There were statistical differences in size between metastatic and benign nodes in terms of maximum diameter, minimum diameter, and volume. Among these, minimum diameter and the shape of the nodes seemed to be the most reliable in suggesting malignancy. A round shape with a longitudinal/transverse ratio of less than 2 of hypoechoic nodes indicated the presence of metastases, and we then performed FNAB. The absence of an echogenic hilum and the presence of cystic portions and calcifications were significantly greater in malignancies than in benign lesions (P<.001). In most cases, metastatic nodules were situated in the lower third of the neck. Reactively enlarged nodes occurred more frequently in the upper part of the neck. CONCLUSIONS: Ultrasonography itself cannot distinguish benign from malignant lesions, but an echographic appearance suggests malignancy and helps in the selection of the node to aspirate with ultrasonographically guided FNAB, which is crucial for a final diagnosis.