Thyroid Fine Needle Aspiration, the Bethesda System, and the BRAFV600E Mutation in Papillary Thyroid Carcinoma: Association and Prediction for Biopsy.

INTRODUCTION: BRAFV600E mutations have been associated with papillary thyroid carcinoma (PTC) histological types including tall-cell and classical, peritumoral infiltration, and nuclear signs, whereas cytological features such as plump cells and sickle nuclei have also been associated with favorable thyroid fine needle aspiration (FNA) results for this tumor. BRAF and RAS are considered early driver mutations that contribute to the development of BRAF-like PTCs and RAS-like PTCs. Our aim was to assess the possible association between all Bethesda System cytological features and thyroid FNAs for PTC and their potential predictive value for future BRAFV600E-related biopsies. METHODS: Our study analyzed 63 cases of PTCs operated on at our hospital over a 5-year period between 2005 and 2017 that had previously undergone FNA and had been classified by the Bethesda System. BRAFV600E was identified by pyrosequencing paraffin-embedded tissues and comparing the cytological signs with the Bethesda System. In addition, a statistical and predictive study of the diagnostic factors "non-follicular," "non-round nuclei," and "non-clear chromatin" was performed to discriminate BRAF-like signs from other hypothetical RAS-like follicular signs. RESULTS: BRAFV600E was detected in 43/63 cases (68.2%). Histological types were significant (p < 0.001), with the classical variant being the most prevalent 31/63 (49.2%) and independent by multivariate analysis odds ratio of 10.58 [2.67; 41.97]. Follicular cytological signs are negatively associated with BRAFV600E: follicular structure (p < 0.001), round nuclei (p = 0.015), and clear chromatin (p = 0.049), while the diagnostic factors: "non-follicular" (positive predictive value [PPV] 82.9, sensitivity 79.1, negative predictive value [NPV] 59.1, specificity 65.0), "non-round nuclei" (PPV 76.6, sensitivity 83.7, NPV 56.3, specificity 45.0), and "non-clear chromatin" (PPV 75.6, sensitivity 79.1, NPV 50.0, specificity 45.0) have predictive value for the mutation. There was no individual significance for the remaining cytological features. CONCLUSIONS: Our study found no association between cytomorphological signs of thyroid FNA and BRAFV600E mutation. Considering the Bethesda System, there is an association (p = 0.045) with numerous cases of mutated PTC in categories V and VI. Our results indicate, however, that the presence of signs referred to as "non-follicular," "non-round nuclei," and "non-clear chromatin" in biopsy of papillary thyroid carcinoma is predictive of BRAF type mutation, whereas follicular signs indicate a RAS type PTC, according to published literature. These results need to be confirmed or modified by further research.

Tumor maligno de la vaina del nervio periférico primario de mama / Malignant peripheral nerve sheath tumor of the breast

Los tumores malignos de la vaina del nervio periférico representan del 5 al 10% del total de tumores malignos de tejidos blandos y frecuentemente se asocian con la neurofibromatosis tipoI. Su presentación en la glándula mamaria es poco frecuente, y el diagnóstico es muy difícil por su rareza y por la ausencia de características clínicas y/o radiológicas específicas, siendo preciso una adecuada interpretación del estudio inmunohistoquímico y su correlación con los hallazgos morfológicos. Presentamos un caso clínico y su revisión bibliográfica

Malignant peripheral nerve sheath tumours represent 5-10% of all malignant soft tissue tumours and are frequently associated with neurofibromatosis typeI. Their presentation in the mammary gland is rare. Because of this rarity, as well as the absence of specific clinical and/or radiological features, their diagnosis very difficult. It is therefore essential to correctly interpret immunohistochemical analysis and its correlation with morphological findings. We present a clinical case and literature review

Abdomen agudo como primera manifestación clínica de endometriosis / Acute abdomen as the first clinical manifestation of endometriosis

La endometriosis en una afección de patrón inflamatorio, con prevalencia en aumento, que puede afectar a cualquier mujer en edad fértil con un amplio abanico de presentaciones clínicas que van desde dismenorrea hasta un cuadro de obstrucción secundario a síndrome adherencial e incluso perforación intestinal. La endometriosis apendicular es una afección poco frecuente, siendo en múltiples ocasiones diagnosticada como apendicitis aguda, que se manifiesta como dolor abdominal recurrente, pudiendo ser la primera manifestación de esta enfermedad ginecológica y que debe ser tenida en cuenta a la hora de realizar el amplio diagnóstico diferencial de dolor abdominal (AU)

Endometriosis is an inflammatory disease that can affect any woman of childbearing age. The incidence of this disease is increasing. Clinical presentations vary widely, ranging from dysmenorrhea to obstructive symptoms, adhesions, and even bowel perforation. Appendiceal endometriosis is rare and is frequently diagnosed as acute appendicitis, which manifests as recurrent abdominal pain. Acute abdomen may be the first manifestation of this gynecological disorder and should be taken into account when making the broad differential diagnosis of abdominal pain (AU)