Lymph Node Dissection in Thymoma: Is it worth it?. (July 2021)

• Record Type: Journal Article
• Authors: Clermidy, Hugo; Maury, Jean-Michel; Collaud, Stéphane; Drevet, Gabrielle; Ginoux, Marylise; Chalabreysse, Lara; Mornex, Françoise; Girard, Nicolas; Tronc, François
• Is Part Of: Lung cancer. Volume 157(2021)
• Page Start: 156
• Page End: 162
• Publication Date: 2021-07
• Subjects: TC thymic carcinoma -- NETT neuroendocrine thymic tumors -- LND Lymph Node Dissection -- IASLC International Association for Studies in Lung Cancer -- ITMIG International Thymic Malignancy Interest Group -- JART Japanese Association for Research in the Thymus -- RYHTMIC National Network for Thymic tumors and malignancies -- UICC Union for International Cancer Control -- WHO World Health Organization -- ESMO European Society for Medical Oncology -- ITCH intra-thoracic chemo hyperthermia -- CT computed tomography -- 18F-FDG-PET fluorine-18-fluorodeoxyglucose positron emission tomography -- SUVMax Maximum Standardized Uptake Value -- FEV1 forced expiratory volume at 1 s -- RLN Recurrent Laryngeal Nerve -- OS overall survival -- FFR Freedom From Recurrence -- VATS video-assisted thoracic surgery -- PN phrenic nerve -- ICU Intensive Care Unit -- SEER Surveillance, Epidemiology, and End Results; Thymoma -- Lymph Node Dissection -- Lymphadenectomy -- Nodal metastases -- Lymph node metastasis; Lungs -- Cancer -- Periodicals; Lung Neoplasms -- Abstracts; Lung Neoplasms -- Periodicals; Poumons -- Cancer -- Périodiques; Lungs -- Cancer; Periodicals; Electronic journals; Electronic journals; 616.99424
• DOI: 10.1016/j.lungcan.2021.05.022
• Languages: English
• ISSNs: 0169-5002

Abstract

Highlights: The incidence of lymph node metastases in thymoma remains unclear. Surgical complications of lymph node dissection are rare. Systematic lymph node dissection did not increase the rate of N positive tumors. Lymph node dissection may not be recommended for smaller, non-invasive thymoma. Lymph node dissection should be discussed for invasive thymomas. Abstract: Objectives: Lymph node dissection (LND) and nodal metastases in thymomas remain controversial and understudied. The aim of our study was to evaluate the incidence of nodal metastasis and the short term outcomes of systematic LND in thymomas. Material and methods: From December 2017 to September 2020, we performed 54 LND conducted according to the International Thymic Malignancy Interest Group (ITMIG) lymph node map. This group was compared to a historical control group of 55 patients who underwent surgery in our center from January 2015 to November 2017. Results: LND was performed in 72 % and in 5 % of the cases in the study cohort group and historical control group, respectively. The number of lymph nodes retrieved was significantly higher in the study cohort group (3.89 per patient vs. 1.62, p = 0.0021). In the whole population studied, nodal metastases were found in 3 patients (2.8 % of all patients) with 5.6 % in the cohort study group vs. 0 % in the control group (p = 0.12). Patients with nodal metastasis had larger tumors (> 7 cm), and a higher histology grade (B2 and B3). There was a trend towards higher risk of laryngeal nerve palsy in the cohort study group (9.3 % vs. 1.8 %, p = 0.11). Conclusion: Systematic LND increases the number of lymph node harvested and detects more lymph node metastases, which remains infrequent in thymomas. The impact of LND and the true prognostic significance of lymph node metastases remains controversial. Given the potential complications, LND or sampling should not be perfomed in small, encapsulated and low grade thymomas.