[An update on parathyroid carcinoma]. / Puesta al día: carcinoma paratiroideo.

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.

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.

[False negative spect parathyroid scintigraphy with sestamibi in patients with primary hyperparathyroidism]. / Análisis de falsos negativos en la cintigrafía SPECT de paratiroides con sestamibi en pacientes con hiperparatiroidismo primario sometidos a cirugía entre 2008-2015 en hospital universitario.

BACKGROUND: 99mTc-sestamibi parathyroid SPECT scintigraphy is a useful tool in the pre-operative study of hyperparathyroidism. False negatives (FN) have been reported in 5.7-14% of the examinations. AIM: To characterize 99mTc-sestamibi FN in cases referred for primary hyperparathyroidism (PHP) to a university hospital. MATERIAL AND METHODS: Descriptive retrospective analysis. We included patients with PHP, studied with SPECT scintigraphy, operated at our center between 2008 and 2015. Clinical and surgical data were recorded; biopsies of the FN were blindly reviewed by one pathologist. RESULTS: One hundred twenty one scintigraphies fulfilled the inclusion criteria. Seven (5.8%) were negative and 114 positive. There was no difference in age, sex and PTH levels between FN and true positive scintigraphies. At surgery, one FN case had two hyperplasic glands and two cases had ectopic glands. Pathology reported adenoma in three cases, hyperplasia in three and carcinoma in one. The largest diameter of the lesion was lower in FN (1.3 and 2.1 cm respectively, p = 0.02) and the proportion of adenomas was higher in true positive cases (29% and 75% respectively; p < 0.01). The interval between scintigraphy and parathyroidectomy was greater in FN with a median of 92 days (range 20 days-3.2 years, p < 0.01). The percentage of oxyphilic cells observed was similar in both groups. CONCLUSIONS: FN parathyroid SPECT scintigraphies in PHP are uncommon. They corresponded to lesions under the equipment's resolution limit and resulted in longer time lags between scintigraphy and surgery.

[Study and management of thyroid nodes by non specialist physicians: SOCHED consensus]. / Estudio y manejo de nódulos tiroideos por médicos no especialistas. Consenso SOCHED.

The thyroid nodule is a frequent cause of primary care consultation. The prevalence of a palpable thyroid nodule is approximately 4-7%, increasing up to 67% by the incidental detection of nodules on ultrasound. The vast majority are benign and asymptomatic, staying stable over time. The clinical importance of studying a thyroid nodule is to exclude thyroid cancer, which occurs in 5 to 10% of the nodules. The Board of SOCHED (Chilean Society of Endocrinology and Diabetes) asked the Thyroid Study Group to develop a consensus regarding the diagnostic management of the thyroid nodule in Chile, aimed at non-specialist physicians and adapted to the national reality. To this end, a multidisciplinary group of 31 experts was established among university academics, active researchers with publications on the subject and prominent members of scientific societies of endocrinology, head and neck surgery, pathology and radiology. A total of 14 questions were developed with key aspects for the diagnosis and subsequent referral of patients with thyroid nodules, which were addressed by the participants. In those areas where the evidence was insufficient or the national reality had to be considered, the consensus opinion of the experts was used through the Delphi methodology. The consensus was approved by the SOCHED board for publication.

Análisis de falsos negativos en la cintigrafía SPECT de paratiroides con sestamibi en pacientes con hiperparatiroidismo primario sometidos a cirugía entre 2008-2015 en hospital universitario / False negative spect parathyroid scintigraphy with sestamibi in patients with primary hyperparathyroidism

Background: 99mTc-sestamibi parathyroid SPECT scintigraphy is a useful tool in the pre-operative study of hyperparathyroidism. False negatives (FN) have been reported in 5.7-14% of the examinations. Aim: To characterize 99mTc-sestamibi FN in cases referred for primary hyperparathyroidism (PHP) to a university hospital. Material and Methods: Descriptive retrospective analysis. We included patients with PHP, studied with SPECT scintigraphy, operated at our center between 2008 and 2015. Clinical and surgical data were recorded; biopsies of the FN were blindly reviewed by one pathologist. Results: One hundred twenty one scintigraphies fulfilled the inclusion criteria. Seven (5.8%) were negative and 114 positive. There was no difference in age, sex and PTH levels between FN and true positive scintigraphies. At surgery, one FN case had two hyperplasic glands and two cases had ectopic glands. Pathology reported adenoma in three cases, hyperplasia in three and carcinoma in one. The largest diameter of the lesion was lower in FN (1.3 and 2.1 cm respectively, p = 0.02) and the proportion of adenomas was higher in true positive cases (29% and 75% respectively; p < 0.01). The interval between scintigraphy and parathyroidectomy was greater in FN with a median of 92 days (range 20 days-3.2 years, p < 0.01). The percentage of oxyphilic cells observed was similar in both groups. Conclusions: FN parathyroid SPECT scintigraphies in PHP are uncommon. They corresponded to lesions under the equipment's resolution limit and resulted in longer time lags between scintigraphy and surgery.

Estudio y manejo de nódulos tiroideos por médicos no especialistas. Consenso SOCHED / Study and management of thyroid nodes by non specialist physicians: SOCHED consensus

The thyroid nodule is a frequent cause of primary care consultation. The prevalence of a palpable thyroid nodule is approximately 4-7%, increasing up to 67% by the incidental detection of nodules on ultrasound. The vast majority are benign and asymptomatic, staying stable over time. The clinical importance of studying a thyroid nodule is to exclude thyroid cancer, which occurs in 5 to 10% of the nodules. The Board of SOCHED (Chilean Society of Endocrinology and Diabetes) asked the Thyroid Study Group to develop a consensus regarding the diagnostic management of the thyroid nodule in Chile, aimed at non-specialist physicians and adapted to the national reality. To this end, a multidisciplinary group of 31 experts was established among university academics, active researchers with publications on the subject and prominent members of scientific societies of endocrinology, head and neck surgery, pathology and radiology. A total of 14 questions were developed with key aspects for the diagnosis and subsequent referral of patients with thyroid nodules, which were addressed by the participants. In those areas where the evidence was insufficient or the national reality had to be considered, the consensus opinion of the experts was used through the Delphi methodology. The consensus was approved by the SOCHED board for publication.

[Clinical features of patients with Basedow Graves disease seen at a university hospital]. / Caracterización de pacientes controlados por enfermedad de Basedow Graves en un hospital universitario.

BACKGROUND: Basedow Graves disease (BGD) is the leading cause of hyperthyroidism. The characteristics of patients seen at a university hospital may differ from those described in the general population. AIM: To describe the clinical features of patients with BGD seen at a university hospital. MATERIAL AND METHODS: Review of medical records of all patients seen at our hospital between 2009 and 2014 with the diagnosis of thyrotoxicosis, hyperthyroidism or BGD. Clinical features, laboratory results and treatments were recorded. RESULTS: We reviewed clinical records of 272 patients; 15 had to be excluded due to incomplete data. BGD was present in 77.9% (n = 212). The mean age of the latter was 42 years (range 10-81) and 76% were women. Ninety six percent were hyperthyroid at diagnosis and thyroid stimulating hormone was below 0.1 mIU/L in all patients. Median free thyroxin and triiodothyronine levels were 3.26 ng/dl and 3.16 ng/ml, respectively. Thyrotropin-receptor antibodies were positive in 98.5% and 85.7% had positive thyroid peroxidase antibodies. Graves orbitopathy (GO) was clinically present in 55% of patients. Of this group, 47% had an active GO, 26% had a moderate to severe disease and 7.8% had sight-threatening GO. As treatment, 26% received radioiodine, 44% anti-thyroid drugs exclusively, 28% underwent thyroidectomy and 2% did not require therapy. CONCLUSIONS: In this group of patients, we observed a greater frequency of severe eye disease and a high rate of surgical management. This finding could be explained by referral to highly qualified surgical and ophthalmological teams.

Association between non-melanoma and melanoma skin cancer rates, vitamin D and latitude.

Vitamin D synthesis takes place in the skin due to solar ultraviolet-B (UVB) radiation. Several studies have shown the association between low sun exposure, non-melanoma skin cancer (NMSC) and a lack of vitamin D synthesis. Since such synthesis in the body depends on the exposure of the skin to solar UVB radiation (290-320 nm), experimental measurements of this type of solar radiation are important. Tarapaca University in Arica, Chile, established a solar UV radiation laboratory in 2006 and since then this laboratory has performed systematic experimental solar UVB measurements using a calibrated biometer instrument. The results, which are presented in the current study, showed the association between NMSC and MSC rates, and the time required to produce 1,000 IU vitamin D with latitudinal variation. Solar UV index (UVI) levels reported in 6 cities from the north to the south of Chile indicated that the UVI ratio of monthly mean values was 1.8 times higher in Arica than in Punta Arenas in January (summer in Chile), whereas it was 14 times higher in June (winter). This factor is an important consideration, since vitamin D synthesis is directly associated with the exposure of individuals to solar UVB radiation. A similar trend was observed in Antofagasta, Santiago, Concepcion, Valdivia and Punta Arenas. It can be concluded from these data that there is a direct association between NMSC rates and mortality, and UVB radiation, meaning that this type of cancer would not depend on vitamin D synthesis and therefore on calcium uptake. By contrast, MSC rates increased with decreased levels of vitamin D, and thus calcium uptake, in all cities, with the only exception being Punta Arenas.

Caracterización de pacientes controlados por enfermedad de Basedow Graves en un hospital universitario / Clinical features of patients with Basedow Graves disease seen at a university hospital

Background: Basedow Graves disease (BGD) is the leading cause of hyperthyroidism. The characteristics of patients seen at a university hospital may differ from those described in the general population. Aim: To describe the clinical features of patients with BGD seen at a university hospital. Material and Methods: Review of medical records of all patients seen at our hospital between 2009 and 2014 with the diagnosis of thyrotoxicosis, hyperthyroidism or BGD. Clinical features, laboratory results and treatments were recorded. Results: We reviewed clinical records of 272 patients; 15 had to be excluded due to incomplete data. BGD was present in 77.9% (n = 212). The mean age of the latter was 42 years (range 10-81) and 76% were women. Ninety six percent were hyperthyroid at diagnosis and thyroid stimulating hormone was below 0.1 mIU/L in all patients. Median free thyroxin and triiodothyronine levels were 3.26 ng/dl and 3.16 ng/ml, respectively. Thyrotropin-receptor antibodies were positive in 98.5% and 85.7% had positive thyroid peroxidase antibodies. Graves orbitopathy (GO) was clinically present in 55% of patients. Of this group, 47% had an active GO, 26% had a moderate to severe disease and 7.8% had sight-threatening GO. As treatment, 26% received radioiodine, 44% anti-thyroid drugs exclusively, 28% underwent thyroidectomy and 2% did not require therapy. Conclusions: In this group of patients, we observed a greater frequency of severe eye disease and a high rate of surgical management. This finding could be explained by referral to highly qualified surgical and ophthalmological teams.