Yang, Ping

Abstract Mutations in the EGFR gene or transcript fusion involving EML4-ALK result in oncogenic activation of these oncogenes driving lung adenocarcinoma growth in tumors carrying such an alteration. For lung adenocarcinoma with these genetic changes, small-molecule tyrosine kinase inhibitors have been highly effective at reducing tumor burden and improve the outcome of the patients. Unfortunately, drug resistance eventually develops in these tumors and challenges remain in controlling lung cancer recurrence after targeted therapy. To overcome recurrence, we initiated a prove-of-principle study to evaluate the feasibility of an integrated strategy utilizing genomic profiles of the tumor and patient-specific tumor xenografts derived (PDX) from biopsies for ex vivo evaluation of antitumor drugs to help guide personalized treatment of lung cancer in patients who have developed resistance to targeted therapy drugs. Our study has three main objectives. 1) Use tumor biopsies obtained at the time of recurrence for oncogene mutation and RNAseq analyses to identify molecular changes in oncogenes and gene pathways that can be potentially targeted. 2) Evaluate drug efficacy and optimize personalized therapy for each patient using PDX models. 3) Assess clinical feasibility and our experience using integrated approaches for lung cancer patients who failed targeted therapy. This study was approved by the Mayo Clinic Institutional Review Board (IRB) and utilizes both clinical and research biopsies. A dedicated nurse study coordinator reviews clinical patient list and history on weekly basis and informs the study team of each potential candidate patient. A total of 30 patients having ALK positive lung cancers have been identified and followed up from nearly 500 potentially ALK positive cases between April 2014 to Sept. 2015. Most patients were never smokers but six were former smokers and two were current smokers. Age at diagnoses ranged from 27-78 years (median = 61). Seven patients (23%) were 45 years or younger at the time of diagnosis. A total of 22 patients are currently being treated with crizotinib while eight are on ceritinib or alectinib. For each biopsy, tumor tissues are obtained using a 20 gauge needle, transferred on ice in preserving media and implanted within one hour into 6-8 week old NOD/SCID mice. Many patients have been on treatment for 2-3 years with stable disease so they do not require biopsy. Using a similar strategy, we also obtained biopsies from patients with EGFR gene mutations in their tumors and have progressed while on targeted therapy. A total of seven cases have been implanted. We will report our experiences in patient selection, clinical follow up, patient consent, PDX development, time from biopsy to tumor establishment, and the results of molecular analyses. Our study enabled us to gain new insights regarding the molecular changes associated with recurring tumors after they have failed targeted therapy as well as clinical experiences on how to utilize state-of-the art approaches and comprehensive genomic information to further improve cancer patient care upon disease progression. Acknowledgements: This work is supported in part by the Hillsberg Award from the National Foundation for Cancer Research and by the Biomarker Discovery Program at the Mayo Clinic Center for Individualized Medicine. Citation Format: Jin Jen, Aaron Mansfield, Patrick W. Eiken, Shawn Stoddard, Karlyn Pierson, Xiaonan Hou, Hong Zheng Ren, Julian Molina, Joanne Yi, Ping Yang. Integrated Approaches to Treating Lung Adenocarcinoma Resistant to Targeted Therapy. [abstract]. In: Proceedings of the AACR Special Conference: Patient-Derived Cancer Models: Present and Future Applications from Basic Science to the Clinic; Feb 11-14, 2016; New Orleans, LA. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(16_Suppl):Abstract nr B34.

Purpose According to the lung cancer staging project, T1a (≤ 2 cm) non–small-cell lung cancer (NSCLC) should be additionally classified into ≤ 1 cm and > 1 to 2 cm groups. This study aimed to investigate the surgical procedure for NSCLC ≤ 1 cm and > 1 to 2 cm. Methods We identified 15,760 patients with T1aN0M0 NSCLC after surgery from the Surveillance, Epidemiology, and End Results database. Overall survival (OS) and lung cancer–specific survival (LCSS) were compared among patients after lobectomy, segmentectomy, or wedge resection. The proportional hazards model was applied to evaluate multiple prognostic factors. Results OS and LCSS favored lobectomy compared with segmentectomy or wedge resection in patients with NSCLC ≤ 1 cm and > 1 to 2 cm. Multivariable analysis showed that segmentectomy and wedge resection were independently associated with poorer OS and LCSS than lobectomy for NSCLC ≤ 1 cm and > 1 to 2 cm. With sublobar resection, lower OS and LCSS emerged for NSCLC > 1 to 2 cm after wedge resection, whereas similar survivals were observed for NSCLC ≤ 1 cm. Multivariable analyses showed that wedge resection is an independent risk factor of survival for NSCLC > 1 to 2 cm but not for NSCLC ≤ 1 cm. Conclusion Lobectomy showed better survival than sublobar resection for patients with NSCLC ≤ 1 cm and > 1 to 2 cm. For patients in whom lobectomy is unsuitable, segmentectomy should be recommended for NSCLC > 1 to 2 cm, whereas surgeons could rely on surgical skills and the patient profile to decide between segmentectomy and wedge resection for NSCLC ≤ 1 cm.