Neoadjuvant in situ gene-mediated cytotoxic immunotherapy improves postoperative outcomes in novel syngeneic esophageal carcinoma models

Esophageal carcinoma is the most rapidly increasing tumor in the United States and has a dismal 15% 5-year survival. Immunotherapy has been proposed to improve patient outcomes; however, no immunocompetent esophageal carcinoma model exists to date to test this approach. We developed two mouse models of esophageal cancer by inoculating immunocompetent mice with syngeneic esophageal cell lines transformed by cyclin-D1 or mutant HRASG12V and loss of p53. Similar to humans, surgery and adjuvant chemotherapy (cisplatin and 5-fluorouracil) demonstrated limited efficacy. Gene-mediated cyototoxic immunotherapy (adenoviral vector carrying the herpes simplex virus thymidine kinase gene in combination with the prodrug ganciclovir; AdV-tk/GCV) demonstrated high levels of in vitro transduction and efficacy. Using in vivo syngeneic esophageal carcinoma models, combining surgery, chemotherapy and AdV-tk/GCV improved survival (P=0.007) and decreased disease recurrence (P<0.001). Mechanistic studies suggested that AdV-tk/GCV mediated a direct cytotoxic effect and an increased intra-tumoral trafficking of CD8 T cells (8.15% vs 14.89%, P=0.02). These data provide the first preclinical evidence that augmenting standard of care with immunotherapy may improve outcomes in the management of esophageal carcinoma

Multiinstitutional Phase 2 Clinical Trial of Intraoperative Molecular Imaging of Lung Cancer

Background. Intraoperative molecular imaging (IMI) may improve surgical outcomes during pulmonary resection for lung cancer. A multiinstitutional phase 2 IMI clinical trial was conducted using a near-infrared, folate receptor-targeted contrast agent for lung adenocarcinomas, OTL38. The primary goal was to determine whether OTL38 improved surgeons' ability to identify difficult to find nodules, occult cancers, and positive margins.Methods. Patients with lung nodules received OTL38 (0.025 mg/kg) preoperatively. Patients had IMI sequentially during lung inspection, tumor resection, and margin check. Efficacy was evaluated by occurrence of clinically significant events, occurrences that caused the surgeon to modify the operation or upstage the patient's cancer. Safety was assessed for a single intravenous dose of OTL38.Results. Of 110 patients recruited, 92 were eligible for analysis. During lung inspection, IMI found 24 additional nodules, 9 (10%) of which were cancers that had not been known preoperatively. During tumor resection, IMI located 11 (12%) lesions that the surgeon could not find. During the margin check, IMI revealed 8 positive margins (9%) that the surgeon thought were negative. Benefits of IMI were pronounced in patients undergoing sublobar pulmonary resections and in patients with ground-glass opacities. There were no serious adverse events. All surgeons felt comfortable with the procedures by 10 cases.Conclusions. In this phase 2 clinical trial, IMI improved outcomes for 26% of patients. A randomized, multiinstitutional phase 3 clinical trial is underway. (C) 2021 by The Society of Thoracic SurgeonsThoracic Surger