Impacto da pandemia de Covid-19 no diagnóstico de neoplasias pulmonares

Abstract

Introduction: Lung cancer has a high incidence and is the most lethal neoplasm. Currently, adenocarcinoma is the predominant histological type, with survival closely related to the disease stage at diagnosis. The Covid-19 pandemic forced urgent adaptations in healthcare services, resulting in a challenging scenario for the prevention, screening, and diagnosis of lung neoplasms. Consequently, a drop in incidence rates and an increase in preventable deaths from the disease were recorded. Simultaneously, the large number of chest computed tomography (CT) scans performed to assess pulmonary involvement by SARS-CoV- 2 enabled the screening of a portion of the population for pulmonary tumors. Objective: To evaluate the impact of the Covid-19 pandemic on the diagnosis of lung neoplasms in Ceará, Brazil, at both population and individual levels. Methods: Histopathological reports, hospitalizations, and diagnostic tests performed during the pandemic at a reference hospital for pulmonary diseases in Ceará were assessed and compared with procedures carried out in previous years. Additionally, pulmonary nodules incidentally diagnosed via CT scans performed for Covid-19 evaluation and referred to the state’s thoracic surgery reference center were characterized according to sociodemographic, clinical, and tumor profiles, including detailed evaluation of PD-L1 immunomodulator expression. Results: The number of surgical pathology reports significantly declined in 2020 and 2021 compared to the annual volumes from 2015 to 2019 (p = 0,0006). However, the positivity rate remained stable (48,4%). A negative correlation was observed between the number of histopathological reports and the number of Covid-19 cases and deaths (p = 0,012 e 0,002 respectively). Thirty-nine patients with incidental pulmonary nodules detected on CT scans for Covid-19 evaluation were referred to the thoracic surgery department. Of these, 14 adenocarcinomas and one squamous cell carcinoma were confirmed. Patients diagnosed with cancer were older, had a higher smoking prevalence, and presented with larger nodules than the 24 patients who remained under clinical and radiological follow-up. Of these, 8 were followed for three years, and only one required surgery after a follow-up CT, with a benign tumor diagnosed. More than half of the neoplasms were in early stages. Only 3 of the 39 patients (7.7%) met the United States Preventive Services Task Force criteria for lung cancer screening, all of whom belonged to the group diagnosed with cancer. Immunohistochemical profiling of the 13 surgically resected tumors revealed considerable variability in the distribution of CD8+ lymphocytes and macrophages. PD-L1 expression showed concordance between tissue microarray (TMA) cores and the surgical specimen. Conclusion: Although the Covid-19 pandemic negatively affected the diagnosis of lung cancer at the population level, it individually benefited some patients by enabling incidental diagnosis of early-stage pulmonary neoplasms. Adenocarcinoma was the predominant histological type among incidental tumors, and immunohistochemical profiling should be cautiously interpreted when using TMAs, due to variability compared to the surgical specimen.