Sentinel lymph node biopsy in papillary thyroid cancer: Accuracy and application in clinical practice.

INTRODUCTION: The presence of lymph nodes metastasis in papillary thyroid cancer (PTC) modifies the type of surgical resection as well as the indication of the treatment with I131 in the postoperative period. This therapeutic approach is based on the results of the diagnostic tests, like the cervical ultrasonography. Currently other methods of diagnostic are tested as selective sentinel lymph node biopsy (SLNB). It can complement to the ultrasound results. The aim was to validate the SLNB for use in the diagnosis of lymph node metastasis by papillary thyroid cancer. METHODS: Observational prospective cohort study of 55 patients who underwent PTC without suspicion of lymph node involvement clinical or radiological, since February 2012 through February 2015, with a follow-up between 6 and 8 years. It was used 99Tc with intratumoral nanocoloid and a portable tube of the gamma camera for the detection of the sentinel node (SN). VARIABLES: age, gender, histological, analytical and preoperative and postoperative staging. The sensitivity, specificity and predictive values of technique was calculated. The validation was determined by calculating the detectability and the false negative results of the test. RESULTS: 53 of the 55 patients (96,36%) there was the SN detection. The FN were 4 patients (7,5%). Of the rest, after applying the SLNB, 24 (48,9%) were kept as N0, 14 (28,5%) became N1a and 11 (22,4%) were classified as N1b. The differences observed in the study were significant (P < ,05). The sensitivity was 86,21%, the specificity of 100%, the PPV was 100% and the NPV of 85.71%. The diagnostic accuracy of 92,45%. CONCLUSION: The SLNB is a valid technique for use in patients suffering from papillary thyroid cancer with a high diagnostic accuracy.

Sentinel lymph node biopsy in papillary thyroid cancer: Accuracy and application in clinical practice. / Ganglio centinela en la metástasis ganglionar por cáncer papilar de tiroides: validez diagnóstica y aplicación en la práctica clínica.

INTRODUCTION: The presence of lymph nodes metastasis in papillary thyroid cancer modifies the type of surgical resection as well as the indication of the treatment with 131I in the postoperative period. This therapeutic approach is based on the results of the diagnostic tests, like the cervical ultrasonography. Currently other methods of diagnostic are tested as selective sentinel lymph node biopsy (SLNB). It can complement to the ultrasound results. The aim was to validate the SLNB for use in the diagnosis of lymph node metastasis by papillary thyroid cancer. METHODS: Observational prospective cohort study of 55 patients who underwent papillary thyroid cancer without suspicion of lymph node involvement clinical or radiological, since February 2012 through February 2015, with a follow-up between 6 and 8 years. It was used 99Tc with intratumoral nanocoloid and a portable tube of the gamma camera for the detection of the sentinel node. VARIABLES: age, gender, histological, analytical and preoperative and postoperative staging. The sensitivity, specificity and predictive values of technique was calculated. The validation was determined by calculating the detectability and the false negative results of the test. RESULTS: In 53 of the 55 patients (96.36%) there was the sentinel node detection. The false negative were 4 patients (7.5%). Of the rest, after applying the SLNB, 24 (48.9%) were kept as N0, 14 (28.5%) became N1a and 11 (22.4%) were classified as N1b. The differences observed in the study were significant (P<.05). The sensitivity was 86.21%, the specificity of 100%, the PPV was 100% and the NPV of 85.71%. The diagnostic accuracy was 92.45%. CONCLUSIONS: The SLNB is a valid technique for use in patients suffering from papillary thyroid cancer with a high diagnostic accuracy.

Reference TSH levels in Spanish pregnant women. Is it possible to unify criteria? / Valores de referencia de TSH en población gestante española. ¿Podemos unificar criterios?

INTRODUCTION: Specific TSH and free thyroxine ranges are needed to adequately assess maternal thyroid function during pregnancy. AIM: The aim of this review is to review studies reporting data on references TSH and free thyroxine levels in Spanish women during the first trimester of pregnancy. MATERIAL AND METHODS: Literature search and selection of studies providing reference TSH ranges in the first trimester of pregnancy. RESULTS: The TSH cut-off point to define hypothyroidism (P97.5) was different depending on the immunoassay used. Gestational age, thyroid autoimmunity, and maternal iodide nutritional status can determine the variability seen in the results. CONCLUSIONS: Differences found in the studies do not allow for establishing a unified TSH reference range. However, results suggest that the TSH upper reference limit is close to 4µU/mL. Reference TSH ranges specific for each population and immunoassay during pregnancy should be defined.

Immunohistochemical detection of the BRAF V600E mutation in papillary thyroid carcinoma. Evaluation against real-time polymerase chain reaction. / Detección inmunohistoquímica de la mutación BRAF V600E en el carcinoma papilar de tiroides. Evaluación frente a la reacción en cadena de la polimerasa en tiempo real.

INTRODUCTION: The BRAF V600E mutation is the most common genetic change in papillary thyroid carcinoma and is associated with a poorer clinical course. Usual methods for its study (DNA sequencing or molecular test based on PCR) are expensive and time-consuming. Recently, immunohistochemistry (IHC) for BRAF mutation has been introduced. OBJECTIVE: To compare the results of IHC and real time PCR (RT-PCR) in the detection of BRAF V600E mutation in papillary thyroid carcinoma. Analysis of clinical and pathological differences depending on RT-PCR results is included. METHODS: A prospective study was performed in 82 consecutive samples, 54 of them taken through a core needle biopsy. IHC was performed on tissue fixed for 24hours with 10% neutral formalin using the anti-BRAF V600E (VE-1) mouse monoclonal primary antibody and was rated as positive or negative. DNA was extracted from formalin-fixed, paraffin-embedded tissues by manual microdissection, and BRAF mutation was detected by RT-PCR using the Cobas® 4800 BRAF V600 mutation test (Roche). RESULTS: Both techniques were concordant in 81 cases, and BRAF was positive in 49. Discordance appeared in a follicular variant showing positive IHC and negative RT-PCR, attributed to histological heterogeneity. Cost of materials for IHC was less than half of the cost for RT-PCR. CONCLUSIONS: IHC appears to be a reliable, economical and easily available alternative to molecular biology techniques for routine detection of the BRAF V600E mutation in papillary thyroid carcinoma patients, provided optimal fixation conditions are used. It may be a useful technique in hospitals with no access to molecular biology techniques.

Consensus statement for use and technical requirements of thyroid ultrasound in endocrinology units. / Criterios sobre la utilización y requerimientos técnicos de la ecografía tiroidea en los servicios de endocrinología y nutrición.

Thyroid nodule detection has increased with widespread use of ultrasound, which is currently the main tool for detection, monitoring, diagnosis and, in some instances, treatment of thyroid nodules. Knowledge of ultrasound and adequate instruction on its use require a position statement by the scientific societies concerned. The working groups on thyroid cancer and ultrasound techniques of the Spanish Society of Endocrinology and Nutrition have promoted this document, based on a thorough analysis of the current literature, the results of multicenter studies and expert consensus, in order to set the requirements for the best use of ultrasound in clinical practice. The objectives include the adequate framework for use of thyroid ultrasound, the technical and legal requirements, the clinical situations in which it is recommended, the levels of knowledge and learning processes, the associated responsibility, and the establishment of a standardized reporting of results and integration into hospital information systems and endocrinology units.