PET/CT imaging in lung cancer: indications and findings

The use of PET/CT imaging in the work-up and management of patients with lung cancer has greatly increased in recent decades. The ability to combine functional and anatomical information has equipped PET/CT to look into various aspects of lung cancer, allowing more precise disease staging and providing useful data during the characterization of indeterminate pulmonary nodules. In addition, the accuracy of PET/CT has been shown to be greater than is that of conventional modalities in some scenarios, making PET/CT a valuable noninvasive method for the investigation of lung cancer. However, the interpretation of PET/CT findings presents numerous pitfalls and potential confounders. Therefore, it is imperative for pulmonologists and radiologists to familiarize themselves with the most relevant indications for and limitations of PET/CT, seeking to protect their patients from unnecessary radiation exposure and inappropriate treatment. This review article aimed to summarize the basic principles, indications, cancer staging considerations, and future applications related to the use of PET/CT in lung cancer

Anéis de Kayser Fleischer

Os anéis de Kayser-Fleischer (K-F) são alterações pigmentadas localizadas na membrana de Descemet, principalmente na região perilímbica na córnea. Estão associadas à doença de Wilson, sendo a manifestação oftalmológica mais comum da mesma e se correlacionam diretamente ao tempo de evolução desta doença. Os anéis de K-F caracterizam-se pela deposição de granulações de cobre de tamanhos e formas variadas na córnea e predominam na periferia corneana. A doença diretamente ligada ao aparecimento dos anéis de K-F, a doença de Wilson, caracteriza-se por distúrbio metabólico com acúmulo de cobre nos tecidos humanos, principalmente no fígado. A presença de anéis pigmentados na córnea nem sempre é diagnóstico de anéis de K-F, devendo ser diferenciados de outras alterações pigmentadas da córnea não ligadas à doença de Wilson. Estas englobam a vasta maioria de doenças hepato-biliares que podem ocasionar acúmulo de cobre, além de corpos estranhos intraoculares contendo cobre, mieloma múltiplo, entre outras. O objetivo do presente artigo é revisar alguns aspectos desta alteração pigmentada corneana, os anéis de K-F, além de descrever algumas características da principal doença ligada ao seu aparecimento.Kayser-Fleischer (K-F) rings are characterized by copper deposition on Descemet’s membrane, mainly near the limbus. They are strongly associated with Wilson’s disease and are the most common ocular finding in this disease. There is an association between the presence of the rings and the time of disease. The K-F rings are composed of small copper granulations of different sizes on the cornea. Wilson’s disease is characterized by an accumulation of copper in the body, primarily in the liver. The occurrence of pigmented rings on the cornea not associated with Wilson’s disease have been reported and must be differentiated from the K-F rings. They occur most often in hepatobiliary diseases, multiple myeloma and ocular copper containing foreign bodies. The purpose of this paper is to review the K-F rings and Wilson’s disease

Anéis de Kayser Fleischer

Os anéis de Kayser-Fleischer (K-F) são alterações pigmentadas localizadas na membrana de Descemet, principalmente na região perilímbica na córnea. Estão associadas à doença de Wilson, sendo a manifestação oftalmológica mais comum da mesma e se correlacionam diretamente ao tempo de evolução desta doença. Os anéis de K-F caracterizam-se pela deposição de granulações de cobre de tamanhos e formas variadas na córnea e predominam na periferia corneana. A doença diretamente ligada ao aparecimento dos anéis de K-F, a doença de Wilson, caracteriza-se por distúrbio metabólico com acúmulo de cobre nos tecidos humanos, principalmente no fígado. A presença de anéis pigmentados na córnea nem sempre é diagnóstico de anéis de K-F, devendo ser diferenciados de outras alterações pigmentadas da córnea não ligadas à doença de Wilson. Estas englobam a vasta maioria de doenças hepato-biliares que podem ocasionar acúmulo de cobre, além de corpos estranhos intraoculares contendo cobre, mieloma múltiplo, entre outras. O objetivo do presente artigo é revisar alguns aspectos desta alteração pigmentada corneana, os anéis de K-F, além de descrever algumas características da principal doença ligada ao seu aparecimento.Kayser-Fleischer (K-F) rings are characterized by copper deposition on Descemet’s membrane, mainly near the limbus. They are strongly associated with Wilson’s disease and are the most common ocular finding in this disease. There is an association between the presence of the rings and the time of disease. The K-F rings are composed of small copper granulations of different sizes on the cornea. Wilson’s disease is characterized by an accumulation of copper in the body, primarily in the liver. The occurrence of pigmented rings on the cornea not associated with Wilson’s disease have been reported and must be differentiated from the K-F rings. They occur most often in hepatobiliary diseases, multiple myeloma and ocular copper containing foreign bodies. The purpose of this paper is to review the K-F rings and Wilson’s disease

PET-CT has low specificity for mediastinal staging of non-small-cell lung cancer in an endemic area for tuberculosis: a diagnostic test study (LACOG 0114)

Abstract Background The present study aims to assess the performance of 18F-FDG PET-CT on mediastinal staging of non-small cell lung cancer (NSCLC) in a location with endemic granulomatous infectious disease. Methods Diagnostic test study including patients aged 18 years or older with operable stage I-III NSCLC and indication for a mediastinal lymph node biopsy. All patients underwent a 18F-FDG PET-scan before invasive mediastinal staging, either through mediastinoscopy or thoracotomy, which was considered the gold-standard. Surgeons and pathologists were blinded for scan results. Primary endpoint was to evaluate sensitivity, specificity and positive and negative predictive values of PET-CT with images acquired in the 1st hour of the exam protocol, using predefined cutoffs of maximal SUV, on per-patient basis. Results Overall, 85 patients with operable NSCLC underwent PET-CT scan followed by invasive mediastinal staging. Mean age was 65 years, 49 patients were male and 68 were white. One patient presented with active tuberculosis and none had HIV infection. Using any SUV_max > 0 as qualitative criteria for positivity, sensitivity and specificity were 0.87 and 0.45, respectively. Nevertheless, even when the highest SUV cut-off was used (SUV_max ≥5), specificity remained low (0.79), with an estimated positive predictive value of 54%. Conclusions Our findings are in line with the most recent publications and guidelines, which recommend that PET-CT must not be solely used as a tool to mediastinal staging, even in a region with high burden of tuberculosis. Trial registration The LACOG 0114 study was registered at ClinicalTrials.gov, before study initiation, under identifier NCT02664792