RESUMO
Introduction: The differential diagnosis between Cushing's disease (CD) and ectopic ACTH syndrome (EAS) is complex, and bilateral inferior petrosal sinus sampling (BIPSS) is considered the gold-standard test. However, BIPSS with corticotropin-releasing hormone (CRH) stimulation is rarely available. Objective: This retrospective cohort study aimed to assess the accuracy of the inferior petrosal sinus to peripheral ACTH gradient (IPS:P) before and after desmopressin stimulation for the differential diagnosis of ACTH-dependent Cushing's syndrome (CS), applying different cutoff values. Methods: A total of 50 patients (48 with CD and 2 with EAS) who underwent BIPSS were included in this study. The sensitivity and specificity of IPS:P in BIPSS before and after desmopressin stimulation were evaluated. Various cutoff values for IPS:P were examined to determine their diagnostic accuracy. Results: Using the traditional IPS:P cutoff, the sensitivity was 85.1% before stimulation, 89.6% after stimulation, and a combined sensitivity of 91.7%. Applying cutoff values of IPS:P >1.4 before and >2.8 after stimulation, the sensitivity was 87.2% and 89.6%, respectively, with a combined sensitivity of 91.7%. Receiver operating characteristic (ROC) curve analysis determined optimal cutoff values of 1.2 before stimulation and 1.57 after stimulation, resulting in a sensitivity of 93.6% and 93.8%, respectively, with a combined sensitivity of 97.9%. Specificity remained at 100% throughout all analyses. Among the 43 patients who responded positively to stimulation, 42 (97.7%) did so within the first three minutes, and all 43 (100%) did so within the first five minutes. None of the assessed clinical variables predicted the ACTH response to stimulation in BIPSS with statistical significance. Discussion: ACTH stimulation with desmopressin during BIPSS improves the accuracy of IPS:P, making it a valuable tool for investigating ACTH-dependent Cushing's syndrome. Considering the low risk of complications, we recommend the use of desmopressin stimulation during BIPSS for the differential diagnosis of ACTH-dependent CS.
Assuntos
Síndrome de ACTH Ectópico , Síndrome de Cushing , Hipersecreção Hipofisária de ACTH , Humanos , Síndrome de ACTH Ectópico/diagnóstico , Hormônio Adrenocorticotrópico/metabolismo , Síndrome de Cushing/diagnóstico , Desamino Arginina Vasopressina/farmacologia , Amostragem do Seio Petroso , Hipersecreção Hipofisária de ACTH/diagnóstico , Estudos RetrospectivosRESUMO
Introducción: El estesioneuroblastoma es un tumor derivado de los neuroblastos del epitelio respiratorio neuroectodérmico. Representa entre el 3 al 6 % de los tumores intranasales. La secreción ectópica de Hormona Adrenocorticotrofina (ACTH) es la causa del 10 al 20 % de Síndrome de Cushing dependiente de ACTH, siendo el estesioneuroblastoma una rara causa de secreción ectópica de ACTH. Presentación del caso: Paciente de sexo femenino de 63 años que consulta por mareos, náuseas, debilidad muscular, y rinorrea de dos años de evolución tratada con corticoides tópicos en forma prolongada. Al examen físico mostraba fenotipo Cushing característico. El laboratorio confirmó valores de ACTH veinte veces por encima de los rangos normales. En IRM cerebral se evidencia lesión expansiva en región etmoidal con compromiso de órbita y base de cráneo. Se resuelve tratamiento quirúrgico ante la necesidad de descompresión tumoral y tratamiento médico para hipercortisolismo en el período pre y posquirúrgico. La anatomía patológica informó proliferación neoplásica maligna de origen neurogénico y las pruebas inmunohistoquímicas confirmaron positividad para ACTH. Comentario: El Síndrome de Cushing por secreción ectópica de ACTH a partir de estesioneuroblastoma es muy poco frecuente, reportándose solo once casos a la fecha en la literatura médica indexada. El tratamiento es complejo y requiere de equipo interdisciplinario. Rev Argent Endocrinol Metab 51:192-196, 2014 Los autores declaran no poseer conflictos de interés.
Introduction: Esthesioneuroblastoma is a tumor originating from the neuroblasts in the neuroectodermal olfactory epithelium. It accounts for 3 % to 6 % of nasal tumors. Adrenocorticotropic hormone (ACTH) ectopic secretion is the cause for 10 % to 20 % of ACTH-dependent Cushing Syndrome cases. Esthesioneuroblastoma constitutes a rare cause of ectopic ACTH secretion. Case presentation: A 63 year-old female patient presented with dizziness, nausea, muscle weakness, and rhinorrhea of two-year duration under long-term treatment with topical corticosteroids. On physical examination, she showed typical Cushingoid phenotype. Brain MRI revealed an expanding lesion in the ethmoid area involving the orbit and the cranial base. Submaxillary metastasis was also detected. Lab tests confirmed ACTH values 20-fold above normal. The patient underwent treatment for hypercortisolism prior to surgery. Surgical treatment was prompted by the need to decompress the tumor. Comment: Esthesioneuroblastoma is a rare tumor. Although approximately 1,000 cases have been published in the last 20 years, only eleven of them were due to ACTH secretion. Treatment is complex and requires an interdisciplinary team. Rev Argent Endocrinol Metab 51:192-196, 2014 No financial conflicts of interest exist.