Beyond bronchoscopic limits: an unusual case of trans-vascular sampling of a venous tumor thrombus of the left superior pulmonary vein

SESSION TITLE: Lung Cancer Global Case Report Posters 1 SESSION TYPE: Global Case Reports PRESENTED ON: 10/10/2023 12:00 pm - 12:45 pm INTRODUCTION: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a well-established diagnostic procedure to evaluate hilar and mediastinal lymphadenopathies and is widely used in clinical practice for lung cancer diagnosis and staging. Moreover, its ultrasound features can be useful to identify peribronchial abnormalities, in particular in vascular structures of the pulmonary hilum. CASE PRESENTATION: A 67-year-old woman suffering from worsening dyspnea presented with a left lung hilar lesion involving the broncho-vascular structures for the left upper lobe. In particular, the superior pulmonary vein appeared infiltrated and with a filling defect of thrombotic nature. Fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) showed a pathological uptake of the left lung lesion and aortopulmonary window lymphadenopathies.The patient underwent a flexible bronchoscopy with EBUS-TBNA: the left main bronchus appeared to be sub-stenotic with hyperemic and easily bleeding mucosa but without evidence of endobronchial lesions. Using the ultrasound probe, the para-aortic adenopathy was visualized but couldn't be sampled due to vascular interposition. Instead, the thrombotic neoplastic infiltration within the left upper pulmonary vein appears visible and two transbronchial fine needle aspirations were performed under ultrasound guidance. The definitive cytological diagnosis confirmed a small cell lung carcinoma (SCLC). DISCUSSION: EBUS-TBNA is currently the procedure of choice for mediastinal staging in NSCLC and for tissue sampling for mediastinal or other lung tumors such as SLCL. More invasive surgical procedures such as mediastinoscopy, mediastinotomy or video-assisted thoracoscopy (VATS) are much less used for the diagnosis of intrathoracic lymphadenopathies due to their invasiveness (1).EBUS-TBNA is a safe technique with high sensitivity (SE 93%, NPV 97%) depending on the size of the lymph node (it is lower for lymphadenopathies ≤1 cm), on the sampled lymph node station (it is higher for station 4R and 7) and on the operator's expertise (2). EBUS has also a role in visualization of parabronchial anatomy, easily differentiating normal parenchyma and hilar structures from malignant tissue by its sonographic appearance. Lung cancer is a known risk factor for pulmonary embolism. The literature already validated the use of EBUS to confirm an endovascular lesion and determine the differential diagnosis between pure pulmonary thromboembolism or neoplastic thromboembolism (3). Trans-vascular diagnostic approach is routinely used in radiological and interventional vascular procedures: in selected cases, this approach may be combined with EBUS-TBNA preserving its safety. This case report describes the possibility of safe trans-vascular access to lung masses. Using EBUS-TBNA trans-vascular diagnostic approach we reached a diagnosis by identifying an unusual target after ruling out the usual lymph node targets. CONCLUSIONS: EBUS-TBNA is a safe and minimally invasive procedure that has become the standard of care in the diagnosis and staging of lung cancer. Its use is increasingly widespreading also due to its possible application not only for lymph nodes sampling but also for lung, mediastinal or even endovascular lesions. In selected cases and in expert hands, an unconventional EBUS-TBNA approach can be the solution for difficult diagnoses. REFERENCE #1: Detterbeck FC, Lewis SZ, Diekemper R, Addrizzo-Harris D, Alberts WM. Executive Summary: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest. 2013 May;143(5 Suppl):7S-37S. REFERENCE #2: Ernst A, Silvestri GA, Johnstone D. American College of Chest Physicians. Interventional pulmonary procedures: Guidelines from the American College of Chest Physicians. Chest. 2003;123:1693–717 REFERENCE #3: Fantin A, Castaldo N, Seides B, Majori M. Pulmonary Embolism as a Finding During Endobronchial Ultrasound: An Occasional Occurrence or a New Element to Be Staged? Cureus. 2021 Dec 3;13(12): e20137 DISCLOSURES: No relevant relationships by Monica Casiraghi No relevant relationships by Cristina Diotti No disclosure on file for Stefano Maria Donghi No disclosure on file for Lara Girelli No relevant relationships by Juliana Guarize No relevant relationships by Clarissa Uslenghi