Puesta al día: carcinoma paratiroideo / An update on parathyroid carcinoma

Parathyroid carcinoma is a rare malignant disease that presents as a sporadic or familial primary hyperparathyroidism (PHP). The latter is associated with some genetic syndromes. It occurs with equal frequency in both sexes, unlike PHP caused by parathyroid adenoma that is more common in women. It should be suspected in cases of severe hypercalcemia, with high parathyroid hormone levels and a palpable cervical mass. Given the difficulty in distinguishing between parathyroid carcinoma and adenoma prior to the surgery, the diagnosis is often made after parathyroidectomy. The only curative treatment is complete surgical resection with oncologic block resection of the primary tumor to ensure free margins. Adjuvant therapies with chemotherapy or radiation therapy do not modify overall or disease-free survival. Recurrences are common and re-operation of resectable recurrent disease is recommended. The palliative treatment of symptomatic hypercalcemia is crucial in persistent or recurrent disease after surgery since morbidity and mortality are more associated with hypercalcemia than with tumor burden.

Recomendaciones para el uso correcto de densitometría ósea en la práctica clínica. Consenso de la Sociedad Chilena de Endocrinología y Diabetes / Guidelines of the Chilean Endocrinology Society for the correct clinical use of bone densitometry

Osteoporosis is a silent and frequent disease, which increases fracture risk. Approximately half of women and one of five men over 50 years old will suffer an osteoporotic fracture throughout their lives. Dual-energy x-ray absorptiometry (DXA) allows a real bone mineral density (BMD) measurement in different parts of the skeleton and is considered the "gold standard" for quantifying osteoporosis with high accuracy and precision. The Board of the Chilean Society of Endocrinology and Diabetes (SOCHED) required from the Bone Disease Study Group to develop a consensus about the "Correct use of bone densitometry in clinical practice in Chilean population". Therefore, we elaborated 25 questions which addressed key aspects about the indications for a DXA scan, and the details of how to perform and report this test. Since some of the evidence obtained was of low quality or inconclusive, we decided to create a multidisciplinary group of national experts in osteoporosis to develop a consensus in this subject. The group consisted of 22 physicians including endocrinologists, gynecologists, geriatricians, radiologists, rheumatologists and nuclear medicine specialists. Using the Delphi methodology to analyze previously agreed questions, we elaborated statements that were evaluated by the experts who expressed their degree of agreement. The final report of this consensus was approved by the SOCHED board.

Aproximación al patrón de normalidad de TSH para la población chilena según Encuesta Nacional de Salud 2009-2010 / Thyroid stimulating hormone reference values derived from the 2009-2010 Chilean National Health Survey

Background: The determination ofthyroid stimulating hormone (TSH) reference values is critical for the diagnosis ofthyroid diseases. Aim: To explore and discuss different definitions to establish TSH reference values using a Chilean national survey sample. Material and Methods: The 2009-2010 Chilean National Health Survey recruited 5,416participants between the ages of 15 and 96years, from all geographic regions of Chile, including urban and rural zones. TSH was measured in a random subsample of 2,785 adults. Median value, 2.5 and 97.5 percentiles were described in three different populations: total survey population, "disease-free population" and the "laboratory kit disease free population". Results: TSH values were higher among women, the elderly and the less educated population. The 97.5 percentile value in the disease-free population was 7.46 uUl/ml. Using this value as a cut-off, hypothyroidism prevalence would be 4.8% in Chile and estimated pharmacological treatment coverage would be 58%. When laboratory kit cut-offs are used, prevalence rises to 22% and treatment coverage drops to 12%. The 2.5 percentile value in the disease-free population was 0.83 uUl/ml, which yields an estimated hyperthyroidism prevalence of3.89%. Conclusions: Median TSH concentration values in the Chilean "disease-free population" are higher than those proposed by laboratory kits and those of developed countries. TSH values in the general population of Chile are also higher in women, the elderly and the less educated population.

Consideraciones para el diagnóstico de linfoma primario de tiroides: esperiencia en 6 casos / Primary thyroid lymphoma: report of six cases

Background: Primary thyroid lymphoma is uncommon but must be suspected in certain clinical situations. Aim: To report a series of six patients with primary thyroid lymphoma. Patients and Methods: Six patients aged 50 to 84 years (five women), treated between 2004 and 2010. All patients had rapidly growing cervical mass; four had compressive signs and symptoms. In three cases the lymphoma was associated to Hashimoto's thyroiditis. Needle biopsy was performed in three patients. In one case was diagnostic for lymphoma and in the other two was suspicious. Five patients had a diffuse large B cell lymphoma, one of them associated to an extranodal marginal zone B cell lymphoma. One patient had a follicular lymphoma. Conclusions: Thyroid lymphoma must be suspected in female patients with rapidly growing cervical mass, older than fifty years, with a nodular goiter suspicious of malignancy (firm, non-tender, fixed and associated to compression signs). The diagnostic must be confirmed with a needle biopsy (fine needle or TrueCut®) and, if it's necessary open biopsy.