ABSTRACT Objective: Our aim was to assess the ability of serum magnesium (Mg), measured on the first postoperative day (Mg1PO), to predict the need for calcium (Ca) replacement in patients undergoing total thyroidectomy (TT). Subjects and methods: Eighty patients undergoing TT, with Mg1PO and PTH dosage in the first (PTH1h) and eighth (PTH8h) hours after TT, were evaluated for the need for Ca replacement. Data were evaluated by uni/multivariate logistic regression and Receiver Operating Characteristic (ROC) curve. Results: 32 patients (40%) required Ca replacement. Median PTH1h, PTH8h and Mg1PO were higher in the no replacement group: 17 versus (vs) 3 pg/mL (p < 0.001), 18.2 vs 3.0 pg/mL (p < 0.001) and 2 vs 1.6 mg/dL (p < 0.001), respectively. Mg1PO was the isolated predictor for this replacement (odds ratio = 0.0004, 95% confidence interval: 0.000003-0.04; p = 0.001), with the cut-off value of 1.8 mg/dL showing sensitivity and specificity of 78.1% and 87.5%, respectively. Conclusions: In this group of patients, serum Mg1PO was the isolated predictor for the need for Ca replacement.

ABSTRACT Objective: Thyrotropin-stimulated thyroglobulin (STg) after total thyroidectomy is a prognosis marker for differentiated thyroid carcinoma (DTC). As Tg level is influenced by thyrotropin (TSH), perhaps the STg/TSH ratio is also a prognosis marker for these tumours. We aimed to compare STg/TSH ratio and first STg level in differentiated thyroid carcinoma patients for their ability to predict the long-term response to initial treatment. Subjects and methods: This retrospective study evaluated data from 181 DTC patients for first (1st) STg and STg/TSH ratio, at 1-3 months post-total thyroidectomy and before iodine-131 therapy, according to response to initial therapy [Excellent/Indeterminate or Incomplete (Biochemical/Structural)] observed at final evaluation, and with the survival time with excellent/indeterminate response. Results: Cases with incomplete response presented higher STg level [225.13 ± 585.26 ng/mL versus (vs) 20.4 ± 192.9 ng/mL; p < 0.001] and STg/TSH ratio (3.01 ± 7.8 vs 0.27 ± 2.58; p < 0.001). Cutoffs of 5 ng/mL for STg and 0.085 for STg/TSH displayed sensitivities of 76.7% and 76.9%, and specificities of 79.2% and 82.6%, respectively, in predicting response to therapy. Values below these cutoffs were associated with longer survival time in excellent/indeterminate response (140.4 vs 15.9 and 144.6 vs 15.9 months, respectively). Conclusion: STg/TSH ratio has a similar performance to the 1st STg in predicting long-term response to initial therapy.

A pesquisa do linfonodo sentinela constitui tratamento padrão para pacientes portadoras de câncer de mama e axila clinicamente negativa. A presença do linfonodo sentinela (LS) extra-axilar e intramamário (IM) ocorre em até 2,6% dos casos, e na presença do LS IM metastático, a positividade axilar pode alcançar até 81%. Na associação do LS IM metastático ao LS axilar não metastático, não há conduta padronizada, visto um limitado número de casos descritos. Adicionamos dois casos à literatura, observando, em um deles, a presença de doença metastática axilar na linfadenectomia complementar. A utilização de nomograma demonstrou que o risco de doença metastática axilar era inferior a 10%, e a adição destes casos à literatura mostrou que, nesta situação, a taxa de doença metastática axilar é de 6,25%. Discutimos os prós e contras da linfadenectomia axilar complementar nesta situação.

The sentinel lymph node biopsy is a standard treatment for patients with breast cancer and clinically negative axilla lymph node. The presence of an extra-axillary and intra-axillary (IM) sentinel lymph node (SLN) occurs in up to 2.6% of cases. In the presence of a metastatic IM SLN, axillary positivity may occur in up to 81% of cases. Due to the limited number of cases reported, there is no standard treatment for the association of metastatic SLN IM and non-metastatic axillary SLN . We add here two cases to the literature, one of them with metastatic disease in the axilla. The use of a nomogram demonstrated that the risk of axillary metastasis was less than 10% and the addition of these cases to the literature showed that in this situation the rate of axillary metastasis is 6.25%. We discuss the pros and cons of further axillary dissection in this situation.

INTRODUÇÃO: Iodoterapia em pacientes com carcinoma diferenciado da tireoide tem o objetivo de reduzir a recorrência tumoral erradicando focos residuais macro e microscópicos. Os efeitos colaterais, em geral, são raros, tênues e transitórios, com pouca repercussão clínica. OBJETIVO: Relatar um caso raro de carcinoma diferenciado da tireoide apresentando grande massa sólida expansiva na base do crânio, com invasão da musculatura mastigatória esquerda e do tecido subcutâneo adjacente, sem invasão do espaço carotídeo que evoluiu com ruptura de carótida pós-iodoterapia. DISCUSSÃO: Os efeitos colaterais pós-iodoterapia são pouco frequentes e, quando presentes, de intensidade discreta. Os eventos adversos graves são muito raros, em especial, aqueles decorrentes de estruturas não invadidas diretamente pelo tecido metastático iodocaptante, como nesse caso, alertando também para a necessidade do aumento dos cuidados na terapia de grandes massas ávidas pelo radioiodo próximas às estruturas nobres.

INTRODUCTION: Radioiodine therapy for patients with differentiated thyroid cancer aims at reducing tumor recurrence by eradicating residual macro- and microscopic foci. Side effects are generally rare, tenuous and transient, with little clinical significance. OBJECTIVE: To report a rare case of differentiated thyroid carcinoma presenting a large expansive solid mass at the base of the skull, with invasion of the left masticatory muscle and adjacent subcutaneous tissue, and without invasion of the carotid space, which evolved to carotid artery rupture following radioiodine therapy. DISCUSSION: Side effects are uncommon after radioiodine therapy and when present, have mild intensity. Serious adverse events are very rare, especially those arising from structures not directly invaded by metastatic tissue with radioiodine uptake, as occurred in this case. This occurrence serves to raise awareness of the need for increased care when using radioiodine therapy on high-avidity masses located close to important structures.