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Although most PMCs have an indolent course, there is a fraction (19% in our series) of patients with PMC and aggressive behavior strongly correlated with some histopathological features (extrathyroid invasion, solid pattern, tumor multifocality, and absence of a capsule) who need to be individualized and for whom a radical therapeutic approach is recommended based on total thyroidectomy and lymphadenectomy followed by radioiodine administration.

The objectives of this study were to assess the reliability of radio-iodine (131I) and a gamma probe for radio-guided surgery (RGS) to detect and then radically dissect lymph node recurrences (LNRs) in 10 patients with differentiated thyroid cancer (DTC). The major inclusion criterion was the presence of an iodine-positive LNR after previous total thyroidectomy and at least two ineffective 131I treatments. The protocol was designed as follows. Day 0: all patients were hospitalized and received 3.7 GBq of 131I in the hypothyroid condition. Day 3: presurgery whole-body scan with a therapeutic dose (TxWBS). Day 5: neck surgery using a gamma probe (Navigator GPS, AutoSuture, Italy), recording the absolute counts and the lesion/background (L/B) counts ratio. Day 7: post-surgery TxWBS performed using the remaining radioactivity. The presurgery TxWBS was positive in all patients, and the post-surgery TxWBS showed a negative pattern in 7 of 10 patients, suggesting the efficacy of the surgical procedure in most of the patients. After RGS the mean decrease in the absolute counts and the L/B counts ratio were 77.6% (52.7% minimum, 94.6% maximum) and 77.4% (52.3% minimum, 94.8% maximum), respectively. After operation the surgeon judged the procedure to be decisive in two patients, favorable in six, and irrelevant in two. The final histologic examination showed the presence of 78 lymph node metastases (mean of 8 per patient). There were 33 neoplastic lesions found by both TxWBS and gamma probe evaluations; 41 were shown only by gamma probe, and 4 were negative by both TxWBS and gamma probe evaluations. This protocol permitted us to look for neoplastic foci with high sensitivity and specificity, and we were able to remove lymph node metastases resistant to radioiodine therapy at a single session. The protocol also allowed detection of some additional tumoral foci in sclerotic areas or behind vascular structures that are difficult to identify and were not seen at the presurgery TxWBS evaluation. However, because of the possible false-negative results, complete excision must be undertaken in high risk patients with a local recurrence to eradicate the largest number of lymph nodes, independent of the counts measured by the gamma probe.

Several studies indicate that in young patients (less than 21 years of age at the time of diagnosis), the prognosis of thyroid carcinoma (TC) is more favorable than in older patients. However, a more radical treatment approach is recommended in children and adolescents due to the higher prevalence of local lymph-node involvement in these cases. Since the extent of primary surgical treatment is closely related to the overall prognosis, preoperative diagnosis becomes essential in the management of thyroid neoplasms in young patients. In this retrospective study (1987-1998), we analyzed a surgical series of 50 children and adolescents with thyroid nodules in an attempt to establish the role of diagnostic studies in detecting malignant lesions prior to surgery. Our diagnostic protocol for evaluating thyroid nodules was based on clinical evaluation, measurement of thyroid-hormone and thyroglobulin (TG) levels, anti-TG and anti-TPO antibody titers, calcitonin, CEA, and TPA levels, sonography, scintigraphy, and fine-needle aspiration cytology (FNAC) of the thyroid nodules and any enlarged lymph nodes. Eleven of the 15 cases of histologically confirmed carcinoma were preoperatively identified as malignant lesions with the aid of FNAC. The authors conclude that the preoperative work-up of children and adolescents with thyroid nodules requires the collaboration of an experienced team of professionals, and recommend FNAC as the initial test.