Clinical and histopathological features of follicular thyroid cancer in Chile

ABSTRACT Objective: Follicular thyroid carcinoma (FTC) is less frequent but has a worse prognosis than papillary carcinoma. The available evidence on pre-operative characteristics of FTC is controversial. Our objective was to characterize the clinical, ultrasound and histopathological presentation of FTC patients treated Chile. Subjects and methods: Retrospective analysis of 97 patients treated for FTC in 6 large centers in Chile. We analyzed their ultrasonographic features and classified the nodules according to ATA risk of malignancy and TI-RADS score, as well as the cytological findings according to the Bethesda system. We described their clinical and histopathological findings at diagnosis and classified their risk of recurrence and mortality according to ATA 2015 recurrence risk category and the eighth edition of the AJCC/UICC staging system, respectively. Results: Median age was 48 years and 73.2% were females. The median diameter was 38.8 mm; only 9.5% of them were microtumors. According to ATA risk of malignancy, 86% of the nodules were low or intermediate suspicious, while 78% were category 3 or 4A nodules according to the TI-RADS. Regarding the Bethesda system, 65.9% had indeterminate cytology (20.6% category III and 45.3% category IV). At histological examination, most were minimally-invasive and angio-invasive tumors with less than 4 foci (54.7% and 28.4% respectively). More than 90% of FTC were unifocal and there was no lymphovascular or extrathyroidal invasion or lymph node involvement. Four patients (4.1%) had distant metastases at diagnosis. Most patients (95%) had stage I or II disease according to the AJCC/UICC staging system, while the risk of recurrence was low at 51.5% when using the ATA risk of recurrence scale. Conclusions: At diagnosis, most FTCs were nodules of low or intermediate suspicion at ultrasound, nearly two thirds had indeterminate cytology according to the Bethesda system, and nearly 50% of them were of low risk of recurrence.

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.

Asociación de niveles de lípidos y haplogrupos Amerindios de DNA mitocondrial en individuos chilenos hipercolesterolémicos tratados con atorvastatina / Association of serum lipid levels and mitochondrial DNA Amerindian haplogroups in hypercholesterolemic subjects receiving atorvastatin

Resumen: Introducción: La respuesta terapéutica a estatuías se ve influenciada por factores como la edad, género y etnicidad. Con respecto a esto, el background genético de la población chilena es predominantemente Amerindio, definido por la presencia de haplogrupos Amerindios A, B, C y D de DNA mitocondrial (mtDNA). Así, el objetivo del estudio fue evaluar la potencial asociación entre la presencia de haplogrupos Amerindios de mtDNA y niveles de lípidos en individuos chilenos hipercolesterolémicos tratados con Atorvastatina. Métodos: Un total de 42 individuos en dos centros de salud del sur de Chile fueron incluidos en el estudio. En el grupo de pacientes se evaluó la presencia de haplogrupos Amerindios de mtDNA por PCR-RFLP, además de la cuantificación de Colesterol Total, Triglicéridos, Colesterol-HDL y Colesterol-LDL, antes y después del tratamiento con Atorvastatina (10 mg/día). Resultados: El 88.1 por ciento de los sujetos presentó algún haplogrupo Amerindio, no observándose diferencias en los niveles de lípidos pre- tratamiento de acuerdo al haplogrupo. Interesantemente, individuos de haplogrupo B presentaron niveles mayores de Colesterol Total (B: 254 +/- 30 mg/dl v/s C: 213 +/- 48 mg/dl, D: 230 +/- 50 mg/dl; p= 0.0319) y Colesterol-LDL (B: 157 +/- 34 mg/dl v/s C: 118 +/- 45 mg/dl, D: 135 +/- 42 mg/dl; p=0.0344) post-tratamiento. Conclusiones: El haplogrupo B se asocia a niveles mayores de lípidos post-tratamiento en pacientes tratados con Atorvastatina. Estos hallazgos sugieren por primera vez, que la presencia de haplogrupo B de mtDNA determinaría una menor respuesta al tratamiento con Atorvastatina en individuos chilenos con background genético amerindio.

Background: Therapeutic response to statins is influenced by age, gender and ethnicity. The genetic background of the Chilean population is predominantly Amerindian, defined by the presence of mitochondrial DNA (mtDNA) Amerindian haplogroups A, B, C and D Amerindian haplogroups and serum lipid levéis in hypercholesterolemic Chilean subjects receiving atorvastatin Methods: 42 subjects from southern Chile were included. The presence of mtDNA Amerindian haplogroups was evaluated by PCR-RFLP; in addition, total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol were measured before and after treatment with atorvastatin 10 mg/day. Aim: to evaluate a possible association of mtDNA. Ameridian haplogroups and serum lipid levels in hypercholesterolemic Chilean subjects receiving atorvastatin. Result: 88.1 percent of subjects exhibited some Amerindian haplogroup. No relation of lipid levels with haplogroups was observed before treatment. Interestingly, haplogroup B individuals had higher levels of total cholesterol compared to other haplogroups after treatment (haplogroup B : 254 +/- 30 mg/dl; C : 213 +/- 48 mg/dl; D : 230 +/- 50 mg/dl, p=0.0319). Corresponding levels for LDL-cholesterol after treatment in the three groups were 157 +/- 34,118 +/-45 and 135 +/-42 mg/ di, respectively, p=0.0344. Conclusion: Compared to other haplogroups, haplogroup B is associated to higher levels of lipids after treatment with atorvastatin. For the first time, these findings suggest that the presence of mtDNA haplogroup B determines a dimished response to atorvastatin in Chilean subjets with an Amerindian genetic background.