Outcomes of thymic epithelial tumors (TETs) with pleural metastases: Real-world insight from RYTHMIC.

8578 Background: TETs are rare and potentially aggressive malignancies with high associated prevalence of autoimmune disorders (AIDs). The pleura is the main metastatic site at relapse, referred as Masaoka-Koga stage (MK) IVa. The benefit of surgical management is unknown, so we have collected outcomes of patients with MK IVa TETs in a large prospective database. Methods: RYTHMIC (Réseau tumeurs THYMiques et Cancer) is a French nationwide network mandated to systematically discuss every case of TETs. The database, hosted by IFCT (Intergroupe Francophone de Cancérologie Thoracique), prospectively includes all consecutive pts with a diagnosis of TET discussed in RYTHMIC national or regional tumor boards. We analyzed epidemiologic, clinical and pathological characteristics of patients (pts) with MK IVa TETs. Results: From January 2012 to December 2019, 2909 pts were included in the database, including 182 MK IVa (6.2%). The median age at diagnosis was 63.5 (range 9 to 91). 58/182 (32%) pts reported AIDs, 76% myasthenia gravis. 129/182 pts had synchronous pleural metastasis. 118/182 (65%) tumors were resected, of them 10 (8.4%) had only pericardial metastases. Thymoma (T) B2 rate was 35.6%, B3 17.8% and thymic carcinoma (TC) 13.5%. Induction chemotherapy (CT) was given in 46 (39%) T and 10 (8%) TC with response rate of 50% and 70% respectively. Thymectomy was performed in addition to pleurectomy in 44 pts (37.2%), pericardiectomy in 68 (57.6%), lung resection in 80 (67.8%) or pneumonectomy in 15 (12.7%). Node resection was performed in 57.6% (n = 67), 12 (18%) were positive. The complete resection rate assessed by surgeons was 57% with a median of 15 (0 to 28) resected pleural metastasis. Intrapleural chemotherapy was added for 19 (16%) pts. No mortality was reported 90 days after surgery procedure. Median follow-up was 36 months. Pleural recurrence was seen in 47 (72%) pts. Median disease-free survival (DFS) was 39 vs 16 months in resected vs not resected tumors (p < 0.0001), 5-years overall survival (OS) was 88 vs 66% (p = 0.28), respectively. Risk of relapse decreased by 60% with surgery (HR = 0.4, 95CI (0.25-0.62); p < 0.0001). Conclusions: The prevalence of MK IVa in our cohort was 6.2%. Surgery appears to be a safe and valid option for pts with MK IVa TET at diagnosis.

Hyperthermic intraoperative intrapleural chemotherapy and surgical cytoreduction as part of multimodal treatment of malignant pleural mesothelioma – case report

Malignant pleural mesothelioma is one of the most aggressive malignancies with a very poor prognosis. Multimodal treatment consisting of three modalities – chemotherapy, radiotherapy and cytoreductive surgery is optimal. The use of new therapeutic modalities, such as hyperthermic intraoperative intrapleural chemotherapy or photodynamic therapy can improve the current results of mesothelioma treatment. Combined hyperthermic intraoperative chemotherapy and cytoreductive surgery as part of multimodal therapy of malignant mesothelioma has been used since 2017 at the 1st Department of Surgery of University Hospital Olomouc. The authors report the case of a 47-year-old man with malignant epithelioid mesothelioma of the left pleural cavity. Following neoadjuvant chemotherapy, this patient underwent extrapleural pneumonectomy with intraoperative intracavitary hyperthermic chemotherapy. The postoperative period was complicated by circulatory instability and later by tension fluidothorax with signs of heart failure. Currently, 8 months have elapsed from the surgery and the patient remains without any signs of recurrence.

Hyperthermic intrapleural chemotherapy combined with endostar by video-assisted thoracoscopic surgery for lung adenocarcinoma with pleural dissemination.

e17542 Background: Patients with lung adenocarcinoma and malignant pleural effusions have limited life expectancy. The treatment of lung adenocarcinoma with malignant pleural effusions remains controversial. The purpose of our study is to evaluate the use of video-assisted thoracoscopy to perform hyperthermic intrapleural chemotherapy combined with Endostar (recombinant human endostatin) for disseminated pleural adenocarcinoma. Methods: From 2007 to 2010, there were 46 patients with lung adenocarcinoma and pleural dissemination undergoing thoracoscopic surgery and intrathoracic hyperthermic perfusion with chemotherapy in combination of Endostar. After thoracoscopic surgery, the hyperthermic perfusion system was set up for hyperthermic intrapleural chemotherapy. The thoracic cavity was perfused at a speed of approximately 1.8-2.3 L/min with 0.9% normal saline (4-5L), containing cisplatinum (100 mg). The intrathoracic temperature remained between 42°C to 43°C. This process of perfusion lasted for 1 hours. Following this, 2L of 0.45% saline with Endostar (30 mg) at a temperature of 30 °C was put into the pleural cavity and kept for 30 min. Results: There were no peri-operative deaths. During the hyperthermic perfusion, patient's core temperature varied from 36.3ºC and 39.3ºC and pulse from 59 beats/m and 126 beats/m. Intraoperative sinus tachycardia occurred in 2 elderly cases. No hematologic toxicity and nephrotoxicity was observed within one week after surgery. Postoperative pneumonia occurred in 1 elderly case. The median survival time was 21 months. During the follow-up period, only one patient suffered from continuing pleural effusion due to atelectasis, one elderly patient died of heart failure one year after surgery and the remaining patients were completely free from pleural effusion during the last follow-up. Conclusions: Hyperthermic intrapleural chemotherapy combined with Endostar by thoracoscopic surgery offers a safe and effective treatment for lung adenocarcinoma with pleural dissemination. It may be time-consuming, but beneficial and may have an encouraging impact on its long-term survival.