RESUMO
INTRODUCTION: Granular cellular tumors are unusual lesions that can occur in the gastrointestinal tract, where they localize most commonly to the esophagus followed by the colon. AREAS COVERED: We report a case of a young man with a sub-epithelial lesion of the ascending colon, removed by endoscopic submucosal dissection. Histological examination revealed a granular cellular tumor without features of malignancy. We present a systematic review of the English literature evaluating granular cellular tumors of lower gastrointestinal tract. EXPERT COMMENTARY: These tumors are usually asymptomatic and discovered incidentally during endoscopy performed for other reasons. Though their histological behavior is usually benign, 1-2% are malignant. Therefore, it is important that these lesions are excised and adequately pathologically characterized.
Assuntos
Neoplasias do Colo/patologia , Tumor de Células Granulares/patologia , Colectomia/métodos , Colo/patologia , Colo/cirurgia , Neoplasias do Colo/cirurgia , Ressecção Endoscópica de Mucosa/métodos , Tumor de Células Granulares/cirurgia , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/cirurgia , Masculino , Adulto JovemRESUMO
Mutations of genes encoding the subunits of the succinate dehydrogenase (SDH) complex were described in KIT/PDGFRA wild-type GIST separately in different reports. In this study, we simultaneously sequenced the genome of all subunits, SDHA, SDHB, SDHC, and SDHD in a larger series of KIT/PDGFRA wild-type GIST in order to evaluate the frequency of the mutations and explore their biological role. SDHA, SDHB, SDHC, and SDHD were sequenced on the available samples obtained from 34 KIT/PDGFRA wild-type GISTs. Of these, in 10 cases, both tumor and peripheral blood (PB) were available, in 19 cases only tumor, and in 5 cases only PB. Overall, 9 of the 34 patients with KIT/PDGFRA wild-type GIST carried mutations in one of the four subunits of the SDH complex (six patients in SDHA, two in SDHB, one in SDHC). WB and immunohistochemistry analysis showed that patients with KIT/PDGFRA wild-type GIST who harbored SDHA mutations exhibited a significant downregulation of both SDHA and SDHB protein expression, with respect to the other GIST lacking SDH mutations and to KIT/PDGFRA-mutated GIST. Clinically, four out of six patients with SDHA mutations presented with metastatic disease at diagnosis with a very slow, indolent course. Patients with KIT/PDGFRA wild-type GIST may harbor germline and/or de novo mutations of SDH complex with prevalence for mutations within SDHA, which is associated with a downregulation of SDHA and SDHB protein expression. The presence of germline mutations may suggest that these patients should be followed up for the risk of development of other cancers.
Assuntos
Complexo II de Transporte de Elétrons/genética , Tumores do Estroma Gastrointestinal/genética , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas c-kit/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Succinato Desidrogenase/genética , Adolescente , Adulto , Idoso , Análise Mutacional de DNA , Complexo II de Transporte de Elétrons/biossíntese , Feminino , Tumores do Estroma Gastrointestinal/patologia , Regulação da Expressão Gênica/genética , Estudos de Associação Genética , Mutação em Linhagem Germinativa , Humanos , Masculino , Proteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas c-kit/metabolismo , Succinato Desidrogenase/biossínteseRESUMO
The assessment of hepatitis C virus (HCV) RNA in liver tissues is clinically relevant in cases where histology, liver function tests, and HCV serology are not sufficient for a definitive diagnosis of HCV-related hepatitis. We analyzed 215 formalin-fixed, paraffin-embedded liver needle biopsies from patients infected with HCV genotypes 1b and 2. HCV RNA extracted from paraffin sections were quantified by means of a TaqMan real-time reverse transcription-polymerase chain reaction method. The quantification of HCV RNA in liver tissue was correlated with the amount of HCV detected by immunohistochemistry (IHC) on paired frozen biopsies, the HCV RNA load in the serum, and the main serum tests of liver function and cholestasis. HCV RNA was detected by real-time reverse transcription-polymerase chain reaction in 169 liver biopsies (78.6%) with a mean value of 13.59+/-37.25 IU/ng. Tissue HCV RNA levels strongly correlated with the IHC results (P<0.001, Spearman test), HCV serum load (P<0.001), aspartate aminotransferase (P=0.001), gamma-glutamyl transpeptidase (P=0.012), and aspartate aminotransferase/alanine aminotransferase ratio (P=0.029). HCV RNA was amplified in up to 7-year-old archival tissue samples. Real-time HCV RNA quantification on archival liver tissue may be clinically relevant in case of "occult" HCV infection or for the diagnosis of patients with known HCV infection and hepatic dysfunction but seronegative for HCV RNA. The assessment of the levels of HCV RNA in the liver might also be important for monitoring the effectiveness of antiviral therapy and the progression of disease in patients with chronic HCV hepatitis.