Utility of EBUS-TBNA in PET-positive mediastinal lymph nodes in subjects with extra-thoracic malignancy

• Published in: PloS one Vol. 14; no. 3; p. e0213437
• Main Authors: Mehta, Ravindra M., Biraris, Pavankumar, Patil, Shekhar, Singla, Abhinav, Kallur, Kumar, Gasparini, Stefano
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 11.03.2019; Public Library of Science (PLoS)
• Subjects: Benign; Biology and Life Sciences; Bronchoscopy; Cancer; CAT scans; Critical care; Dermatology; Development and progression; Diagnosis; Discordance; Endoscopic Ultrasound-Guided Fine Needle Aspiration - methods; Etiology; Etiology (Medicine); Female; Health aspects; Hospitals; Humans; Liver cancer; Lung cancer; Lymph nodes; Lymph Nodes - diagnostic imaging; Lymphatic Metastasis - diagnostic imaging; Lymphatic system; Lymphocytes; Male; Malignancy; Mediastinal Neoplasms - diagnostic imaging; Mediastinum - diagnostic imaging; Medical diagnosis; Medical research; Medicine; Medicine and Health Sciences; Middle Aged; Neoplasm Staging; Neoplasms - diagnostic imaging; Oncology; Pathology; Patients; Positron emission; Positron emission tomography; Positron Emission Tomography Computed Tomography; Retrospective Studies; Sarcoidosis; Skin; Sleep; Sport utility vehicles; Statistical analysis; Thorax; Tomography; Tuberculosis; Tumors; Ultrasonic imaging; Ultrasound; Ultrasound imaging; Urology; Italy; India
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0213437

Patients with primary extra-thoracic malignancy (ETM) often have hyper-metabolic mediastinal lymph nodes (HM-MLN) in the PET-scan done for initial staging or post treatment follow-up. There is scant data on the etiology of HM-MLN in such patients, which can also be due to non-malignant causes. We used endobronchial ultrasound (EBUS) guided sampling to determine the etiology of HM-MLN in patients with ETM and study the relationship between PET-SUV values and a diagnosis of malignancy in this population. 65 consecutive patients, from March 2013 to March 2017 with either known ETM for primary staging or post-treatment follow-up, with PET CT showing HM-MLN (SUV > 2.5) were included in the study. 65 patients with ETM had EBUS-TBNA for HM-MLN. 20/65 (30.7%) were malignant, 45/65 (69.23%) were benign MLN. In patients with benign etiology of HM-MLN, 6/45 (13.3%) had necrotising granulomatous, 24/45 (53.3%) had non- necrotising granulomatous MLN and 15/45 (33.3%) had reactive MLN. We found discordance (i.e. primary ETM responded to treatment and a new HM-MLN was detected) in 21/65 (32.3%) patients with PET-CT done for initial ETM staging, and 44/65 (67.7%) with a post-treatment PET-CT. showed. Correlating SUV with diagnoses, the SUV values in EBUS-proven malignant MLN were 8.9 ± 4.1, while they were 10.2 ± 5.57 in benign MLN. There was no statistically significant difference between the SUV of benign and malignant MLNs. This study shows a significant incidence of EBUS-TBNA proven benign diagnoses 45/65 (69.2%) in 'SUV-deemed-malignant MLN' and a poor relationship between high SUV and malignant MLN, in patients with known ETM. The ETM related HM-MLN have a significant chance of being benign, and a tissue diagnosis is imperative as it impacts on the treatment plan and prognosis.