Genetic Screening of Patients with Thyrotoxic Hypokalemic Periodic Paralysis: An Experience from a Tertiary Care Hospital in the Northeast of Brazil.

BACKGROUND: Thyrotoxic Hypokalemic Periodic Paralysis (THPP) is a rare neuromuscular disease characterized by recurrent episodes of skeletal muscle weakness associated with hypokalemia. Alterations in protein-encoding genes that are part of ion channels seem to be related to the development of this disease. However, the pathogenic potential of some variants in these genomic regions is not yet fully understood. The aim of this study was to screen genetic alterations in regions coding for calcium (cav1.1), sodium (nav1.4), and potassium (Kir2.6) channels, evaluating its impact on the phenotype of patients with THPP. METHODS: Four patients with a diagnosis of THPP followed by the Endocrinology Service of the University Hospital of the Federal University of Maranhão (Brazil) were investigated for the presence of molecular abnormalities in CACNA1S, SCN4A, and KCNJ18 genes. RESULTS: The KCNJ18 analysis revealed at least one polymorphic variant in each patient. Considering the haplotypic classification of R39Q, R40H, A56E, and I249V variants, two cases were named Kir2.6_RRAI and the other two patients were named Kir2.6_QHEV. No patient had point mutations in the regions evaluated for CACNA1S and SCN4A genes. CONCLUSION: The identification of the Kir2.6_RRAI and Kir2.6_QHEV haplotypes reinforces the existence of two main haplotypes involving these four loci of the KCNJ18gene. On the other hand, point mutations in CACNA1S, SCN4A, and KCNJ18 genes do not seem to be the main mechanism of pathogenesis of THPP, indicating that many questions about this topic still remain unclear. So, the diagnosis of this rare disorder should still be based on clinical and biochemical aspects presented by the patient.

Does the Bethesda category predict aggressive features in differentiated thyroid cancer?

OBJECTIVE: To analyze the importance of preoperative cytology of thyroid nodules and its relationship with mortality risk, recurrence risk, dynamic stratification, and aggressive characteristics (vascular invasion, aggressive histology, incomplete tumor resection, extrathyroidal extension of the tumor, and presence of lymph node and distant metastases). SUBJECTS AND METHODS: Retrospective evaluation of 153 patients diagnosed with differentiated thyroid carcinoma (DTC) and following up at the Hospital Universitário Presidente Dutra between January 1999 and December 2016. RESULTS: In all, 96% of the patients were female, 79.7% had papillary carcinoma and the most common fine-needle aspiration (FNA) result was Bethesda II (29.4%). The mean age was 43.11 ± 12.8 years. Overall, 85% of the patients progressed without any evidence of disease. There was a statistically significant relationship between the presurgical FNA and the presence of extrathyroidal extension, vascular invasion, and lymph node metastasis. CONCLUSIONS: The preoperative cytology of the nodule may have an impact on the follow-up of patients with DTC. Future studies in a larger population are required to confirm this finding.

Does the Bethesda category predict aggressive features in differentiated thyroid cancer?

ABSTRACT Objective: To analyze the importance of preoperative cytology of thyroid nodules and its relationship with mortality risk, recurrence risk, dynamic stratification, and aggressive characteristics (vascular invasion, aggressive histology, incomplete tumor resection, extrathyroidal extension of the tumor, and presence of lymph node and distant metastases). Subjects and methods: Retrospective evaluation of 153 patients diagnosed with differentiated thyroid carcinoma (DTC) and following up at the Hospital Universitário Presidente Dutra between January 1999 and December 2016. Results: In all, 96% of the patients were female, 79.7% had papillary carcinoma and the most common fine-needle aspiration (FNA) result was Bethesda II (29.4%). The mean age was 43.11 ± 12.8 years. Overall, 85% of the patients progressed without any evidence of disease. There was a statistically significant relationship between the presurgical FNA and the presence of extrathyroidal extension, vascular invasion, and lymph node metastasis. Conclusions: The preoperative cytology of the nodule may have an impact on the follow-up of patients with DTC. Future studies in a larger population are required to confirm this finding.

Pituitary Metastasis of Thyroid Carcinoma: A Case Report.

BACKGROUND Pituitary metastasis of thyroid carcinoma is a rare entity. Differential diagnosis with other lesions in the sellar/parasellar region, through clinical, histopathological, immunohistochemical, and imaging is challenging but essential for adequate treatment. CASE REPORT This case report describes a 58-year-old patient with the previous diagnosis of follicular thyroid carcinoma, with metastasis to cervical lymph nodes, bone, and lung, initially evolving to left palpebral ptosis. In the investigation, laboratory tests showed hypopituitarism, and magnetic resonance imaging of the skull showed a suprasellar formation measuring 2.2×3.5×2.5 cm, which increased in size in a few months. The patient underwent transcranial neurosurgery and subsequent immunohistochemical analysis, which confirmed pituitary metastasis of follicular thyroid carcinoma. The patient underwent chemotherapy and radiotherapy but died 26 months after the onset of symptoms. CONCLUSIONS The differential diagnosis of pituitary metastasis from a benign lesion is difficult. Therefore, a careful analysis of the history and clinical evolution, use of complementary imaging tests, and, where possible, the histopathological and immunohistochemical analysis of the lesion for diagnostic elucidation are necessary.

Correlation between dermoscopic and histopathological diagnoses of atypical nevi in a dermatology outpatient clinic of the Medical School of São José do Rio Preto, SP, Brazil.

BACKGROUND: The incidence of cutaneous melanoma is increasing worldwide. Since it is an aggressive neoplasm, it is difficult to treat in advanced stages; early diagnosis is important to heal the patient. Melanocytic nevi are benign pigmented skin lesions while atypical nevi are associated with the risk of developing melanoma because they have a different histological pattern than common nevi. Thus, the clinical diagnosis of pigmented lesions is of great importance to differentiate benign, atypical and malignant lesions. Dermoscopy appeared as an auxiliary test in vivo, playing an important role in the diagnosis of pigmented lesions, because it allows the visualization of structures located below the stratum corneum. It shows a new morphological dimension of these lesions to the dermatologist and allows greater diagnostic accuracy. However, histopathology is considered the gold standard for the diagnosis. OBJECTIVES: To establish the sensitivity and specificity of dermoscopy in the diagnosis of pigmented lesions suspected of malignancy (atypical nevi), comparing both the dermatoscopic with the histopathological diagnosis, at the Dermatology Service of the outpatient clinic of Hospital de Base, São José do Rio Preto, SP. METHODS: Analysis of melanocytic nevi by dermoscopy and subsequent biopsy on suspicion of atypia or if the patient so desires, for subsequent histopathological diagnosis. RESULTS: Sensitivity: 93%. Specificity: 42%. CONCLUSIONS: Dermoscopy is a highly sensitive method for the diagnosis of atypical melanocytic nevi. Despite the low specificity with many false positive diagnoses, the method is effective for scanning lesions with suspected features of malignancy.

Correlation between dermoscopic and histopathological diagnoses of atypical nevi in a dermatology outpatient clinic of the Medical School of São José do Rio Preto, SP, Brazil / Correlação entre os diagnósticos dermatoscópico e histopatológico de nevos atípicos no ambulatório de dermatologia da Faculdade de Medicina de São José do Rio Preto, SP, Brasil

BACKGROUND: The incidence of cutaneous melanoma is increasing worldwide. Since it is an aggressive neoplasm, it is difficult to treat in advanced stages; early diagnosis is important to heal the patient. Melanocytic nevi are benign pigmented skin lesions while atypical nevi are associated with the risk of developing melanoma because they have a different histological pattern than common nevi. Thus, the clinical diagnosis of pigmented lesions is of great importance to differentiate benign, atypical and malignant lesions. Dermoscopy appeared as an auxiliary test in vivo, playing an important role in the diagnosis of pigmented lesions, because it allows the visualization of structures located below the stratum corneum. It shows a new morphological dimension of these lesions to the dermatologist and allows greater diagnostic accuracy. However, histopathology is considered the gold standard for the diagnosis. OBJECTIVES: To establish the sensitivity and specificity of dermoscopy in the diagnosis of pigmented lesions suspected of malignancy (atypical nevi), comparing both the dermatoscopic with the histopathological diagnosis, at the Dermatology Service of the outpatient clinic of Hospital de Base, São José do Rio Preto, SP. METHODS: Analysis of melanocytic nevi by dermoscopy and subsequent biopsy on suspicion of atypia or if the patient so desires, for subsequent histopathological diagnosis. RESULTS: Sensitivity: 93%. Specificity: 42%. CONCLUSIONS: Dermoscopy is a highly sensitive method for the diagnosis of atypical melanocytic nevi. Despite the low specificity with many false positive diagnoses, the method is effective for scanning lesions with suspected features of ...

FUNDAMENTOS: A incidência do melanoma cutâneo tem aumentado mundialmente e, por ser uma neoplasia agressiva de difícil tratamento em estágios avançados, o diagnóstico precoce é fundamental para cura do paciente. Os nevos melanocíticos são lesões pigmentadas benignas da pele, enquanto os nevos atípicos, por possuírem padrão histológico diferente dos nevos comuns, estão associados ao risco de desenvolvimento de melanoma cutâneo. Dessa forma, o diagnóstico clínico das lesões pigmentadas é de grande importância para diferenciar lesões benignas, atípicas e malignas. A dermatoscopia surgiu como um exame auxiliar in vivo, com papel fundamental no diagnóstico de lesões pigmentadas. Como permite a visualização das estruturas localizadas abaixo do estrato córneo, traz uma nova dimensão morfológica dessas lesões para o dermatologista, permitindo maior precisão diagnóstica, porém, o diagnóstico padrão ouro é a histopatologia. OBJETIVOS: Estabelecer a sensibilidade e especificidade da dermatoscopia no Serviço de Dermatologia do Ambulatório do Hospital de Base da cidade de São José do Rio Preto, SP, no diagnóstico de lesões pigmentadas com suspeita de malignidade (nevos atípicos), comparando o diagnóstico dermatoscópico ao histopatológico. MÉTODOS: Análise de nevos melanocíticos por dermatoscopia e conseqüente biópsia em caso de suspeita de atipia, ou caso o paciente desejar, para realizar posterior diagnóstico histopatológico. RESULTADOS: Sensibilidade: 93%. Especificidade: 42%. ...