Malignant pericardial effusion complicated by cardiac tamponade under atezolizumab

Abstract

Immune-related adverse events including cardiac toxicity are increasingly described in patients receiving immune checkpoint inhibitors. We described a malignant pericardial effusion complicated by a cardiac tamponade in an advanced non-small cell lung cancer patient who had received five infusions of atezolizumab, a PDL-1 monoclonal antibody, in combination with cabozantinib. The definitive diagnosis was quickly made by cytology examination showing typical cell abnormalities and high fluorescence cell information provided by the hematology analyzer. The administration of atezolizumab and cabozantinib was temporarily discontinued due to cardiogenic hepatic failure following cardiac tamponade. After the re-initiation of the treatment, pericardial effusion relapsed. In this patient, the analysis of the pericardial fluid led to the final diagnosis of pericardial tumor progression. This was afterwards confirmed by the finding of proliferating intrapericardial tissue by computed tomography scan and ultrasound. This report emphasizes the value of cytology analysis performed in a hematology laboratory as an accurate and immediate tool for malignancy detection in pericardial effusions.

Keywords: Pericardial effusion; atezolizumab; cytology; fluorescence; non-small cell lung cancer.

Figure 1.

Body fluid scattergram. WBC differential fluorescence (WDF) scattergram of the patient’s pericardial effusion showed high fluorescent cells (HF-BF# = 0.132 × 10⁹/L). The greater dispersion of these cells reflects a wide heterogeneity of nucleic acid content and internal cell structure (red ellipse). SFL: side fluorescence; SSC: side scatter.

Figure 2.

Cytological morphology. Cytomorphological analysis on the collected pericardial effusion was carried out after a cytospin and the May–Grünwald–Giemsa staining method. It highlighted giant basophilic cells compared to a normal neutrophil (a). Some cells accumulated numerous morphological characteristics typical of malignancy including multinuclearity (b), nuclear blebs (c), several large irregular nucleoli (d), asymmetrical mitotic figure (e), and images of cannibalism (f). No acute inflammatory cells were visualized. Magnification: 100×.

Figure 3.

CT scan. Pericardial tumor nodules (blue arrow) were seen on the CT scan performed at further tumor progression 2 months after the acute cardiac failure.