SUMMARY We report a rare case of Cushing’s syndrome in a 37-year-old female who initially presented with localized acinic cell carcinoma of the parotid gland. In January 2014, she underwent a right parotidectomy with facial nerve preservation and adjuvant radiotherapy. In August 2018, she presented a histologically-proven local regional relapse. The patient was considered for salvage surgery with facial nerve sacrifice and remained with no evidence of disease. One year later the patient developed pulmonary dissemination and started to gain weight and developed facial plethora and acne on the face and upper trunk. In a physical examination, the patient presented moon face, buffalo hump, acne and stage 2 hypertension. Biochemical evaluation confirmed ACTH-dependent Cushing’s syndrome. IHC for ACTH in the lung biopsy revealed strong positive staining for ACTH confirming a diagnosis of ectopic ACTH secretion by a metastatic parotid acinic cell carcinoma. Ketoconazole (600 mg/d) was started to treat the CS. In addition, as chemotherapy was initiated to treat the metastatic disease. After the fifth cycle of chemotherapy, ketoconazole was suspended and the patient remained in remission of CS for four months, when CS recurred. A unique feature of this case is related to the clinical CS relapse associated with disease progression, which needed prompt treatment with ketoconazole, resulting in a significant improvement in the patient’s condition. Although rare, should be attentive for possible CS features in patients with high-grade salivary gland carcinomas, since the diagnosis of ectopic secretion of ACTH may significantly impact their management and outcomes.

RESUMO Introdução: Vários preparados podem ser utilizados na citologia diagnóstica, como esfregaços (SM), preparados do tipo meio líquido (ML) e emblocado em parafina ou cell block (CB). Objetivo: Avaliar a qualidade do CB, além dos espécimes citológicos convencionais, em casos de biópsia aspirativa por agulha fina (BAAF) de nódulos de tireoide na rotina diagnóstica. Método: Cento e seis casos consecutivos de BAAF de nódulos de tireoide foram avaliados independentemente por dois citopatologistas (Obs1 e Obs2) quanto à celularidade dos preparados de SM, ML e CB. Resultados: A celularidade foi rica/moderada em 56 (52,8%) CB para ambos observadores. ML mostrou celularidade rica/moderada em 86 (81,1%) casos para o Obs1 e 91 (85,8%) para o Obs2; desses casos, CB mostrou a mesma celularidade em 52/86 (60,4%) casos para o Obs1 e 54/91 (59,3%) para o Obs2. SM mostrou celularidade rica/moderada em 86 (81,1%) casos para o Obs1 e 87 (82%) para o Obs2; desses casos, CB apresentou a mesma celularidade em 48/86 (55,8%) casos para o Obs1 e 54/87 (62%) para o Obs2. A celularidade do CB foi maior do que a do ML em apenas cinco casos para o Obs1 e três para o Obs2. ML foi avaliado como escasso/ausente em apenas cinco (4,7%) e seis (5,6%) casos para os Obs1 e Obs2, respectivamente. Conclusão: CB pode ser utilizado rotineiramente como espécime adicional no material obtido de BAAF de nódulos de tireoide, sem prejuízo dos espécimes de meio líquido, o que possibilita a realização de estudo complementar, principalmente imuno-histoquímico e molecular.

ABSTRACT Introduction: Various preparations can be used in diagnostic cytology, including conventional smears (CS), liquid-based preparations (LBP) and cell block (CB). Objective: The aim of this study is to evaluate the quality of CB preparations in addition to conventional cytological specimens in cases of fine-needle aspiration biopsy (FNAB) of thyroid nodules in diagnostic routine. Method: One hundred and six consecutive cases of FNAB routine thyroid nodules were independently evaluated by two cytopathologists (Obs1 and Obs2) on the cellularity of SM, LBP and CB. Results: The cellularity was rich/moderate in 56 (52.8%) CBs for both observers. LBP showed rich/moderate cellularity in 86 (81.1%) cases for Obs1 and 91 (85.8%) for Obs2; among these cases, CB showed the same cellularity in 52/86 (60.4%) cases for Obs1 and 54/91 (59.3%) for Obs2. SM showed rich/moderate cellularity in 86 (81.1%) cases for Obs1 and 87 (82%) for Obs2; among these cases, CB showed the same cellularity in 48/86 (55.8%) cases for Obs1 and 54/87 (62%) for Obs2. CB cellularity was higher than that in LBP in only five cases for Obs1 and three for Obs2. LBP was assessed as low/absent in only five (4.7%) and six (5.6%) cases for Obs1 and Obs2, respectively. Conclusion: CB can be routinely used as additional specimen in material obtained from thyroid nodules FNAB, without adversely affecting LBP specimens, enabling the conduction of further immunohistochemical and molecular studies.

OBJECTIVE: To analyze glucose transporter 1 expression patterns in malignant tumors of various cell types and evaluate their diagnostic value by immunohistochemistry. INTRODUCTION: Glucose is the major source of energy for cells, and glucose transporter 1 is the most common glucose transporter in humans. Glucose transporter 1 is aberrantly expressed in several tumor types. Studies have implicated glucose transporter 1 expression as a prognostic and diagnostic marker in tumors, primarily in conjunction with positron emission tomography scan data. METHODS: Immunohistochemistry for glucose transporter 1 was performed in tissue microarray slides, comprising 1955 samples of malignant neoplasm from different cell types. RESULTS: Sarcomas, lymphomas, melanomas and hepatoblastomas did not express glucose transporter 1. Fortyseven per cent of prostate adenocarcinomas were positive, as were 29% of thyroid, 10% of gastric and 5% of breast adenocarcinomas. Thirty-six per cent of squamous cell carcinomas of the head and neck were positive, as were 42% of uterine cervix squamous cell carcinomas. Glioblastomas and retinoblastomas showed membranous glucose transporter 1 staining in 18.6% and 9.4% of all cases, respectively. Squamous cell carcinomas displayed membranous expression, whereas adenocarcinomas showed cytoplasmic glucose transporter 1 expression. CONCLUSION: Glucose transporter 1 showed variable expression in various tumor types. Its absence in sarcomas, melanomas, hepatoblastomas and lymphomas suggests that other glucose transporters mediate the glycolytic pathway in these tumors. The data suggest that glucose transporter 1 is a valuable immunohistochemical marker that can be used to identify patients for evaluation by positron emission tomography scan. The function of cytoplasmic glucose transporter 1 in adenocarcinomas must be further examined.