Emprego do 18F-FDG em PET/CT no sistema único como alternativa de método não-invasivo para o estadiamento do câncer de pulmão

• Ano de defesa: 2021
• Autor(a) principal: Anflor Junior, Luís Carlos
• Orientador(a): Hochhegger, Bruno
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul
• Programa de Pós-Graduação: Programa de Pós-Graduação em Medicina e Ciências da Saúde
• Departamento: Escola de Medicina
• País: Brasil
• Palavras-chave em Português: PET-CT; Câncer de Pulmão Não-Pequenas Células; Mediastinoscopia
• Palavras-chave em Inglês: PET-CT; Non-Small Cell Lung Cancer; Mediastinoscopy
• Área do conhecimento CNPq: CIENCIAS DA SAUDE::MEDICINA
• Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/10108

Background: The evaluation of the performance of PET-CT in the staging of non-small cell lung cancer (NSCLC) in an endemic area of granulomatous disease is of clinical relevance. Objective: To evaluate the performance of PET-CT in mediastinal staging of patients with NSCLC residing in an endemic area of tuberculosis. Secondly, to evaluate the performance of the exam considering also the variation of the image capture obtained in the second hour after using the radiopharmaceutical. 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: The findings of the present study 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.