A retrospective study evaluating the pretreatment tumor volume (PTV) in non-small cell lung cancer (NSCLC) as a predictor of response to program death-1 (PD-1) inhibitors

• Main Authors: Nagasaka M, Abdallah N, Crosby M, Thummala N, Patel D, Wozniak AJ, Gadgeel S, Abrams J, Sukari A
• Format: Article
• Language: English
• Published: Dove Medical Press 2019-09-01
• Series: Lung Cancer : Targets and Therapy
• Subjects: non-small cell lung cancer; tumor volume; tumor burden; checkpoint inhibitors
• Online Access: https://www.dovepress.com/a-retrospective-study-evaluating-the-pretreatment-tumor-volume-ptv-in--peer-reviewed-article-LCTT

Misako Nagasaka,1,2 Nadine Abdallah,3 Marcus Crosby,4 Nithin Thummala,1 Dhaval Patel,1 Antoinette J Wozniak,5 Shirish Gadgeel,6 Judith Abrams,1 Ammar Sukari1 1Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, USA; 2Department of Advanced Medical Innovations, St. Marianna University Graduate School of Medicine, Kawasaki, Japan; 3Department of Internal Medicine, Wayne State University, Detroit, MI, USA; 4Department of Radiation Oncology, Gundersen Health System, La Crosse, WI, USA; 5Department of Oncology, University of Pittsburgh, Pittsburgh, PA, USA; 6Department of Internal Medicine, Division of Hematology and Oncology, University of Michigan, Ann Arbor, MI, USACorrespondence: Ammar SukariDepartment of Oncology, Karmanos Cancer Institute, Wayne State University, 4100 John R, Detroit, MI 48201, USATel [phone]Fax [phone]Email [e-mail] of hypothesis: Little information is available regarding the imaging characteristics that assist in differentiating responders from non-responders. We hypothesized that patients with higher pretreatment tumor volume (PTV) would have lower response rates and shorter overall survival (OS).Methods: Data from patients who received at least one dose of program death-1 (PD-1) inhibitors before August 31, 2016 were captured from our institution’s pharmacy database. The primary objective was to determine the association of PTV with best response, evaluated utilizing RECIST v1.1 criteria. Secondary objectives were estimation of progression-free survival (PFS) and OS. PTV was measured using the Philips Intellispace Multi-Modality Tumor Tracking application.Results: 116 non-small cell lung cancer (NSCLC) patients were evaluated. 66% patients had adenocarcinoma, 28% had squamous cell carcinoma and 5% had poorly differentiated NSCLC. Median PTV was 53.7 cm3 (95% CI: 13.3–107.9). Only one individual had no metastases and the remainder had M1 disease; 38% M1a, 10% M1b, 51% M1c. Most (79%) were previously treated. There were no complete responses; among those followed for at least 6 weeks, 26% had a partial response, 39% stable disease and 34% PD; 4% had no recorded response. There were no strong associations of PTV with any of the demographic or clinical characteristics. There was no association between PTV and OS (HR 1.2, P=0.26) or PFS (HR 1.1, P=0.47). Liver metastasis was associated with shorter survival (HR=2.8, P=0.05).Conclusion: PTV in NSCLC did not prove to be a predictor of response to PD-1 inhibitors but having liver metastasis was associated with significantly shorter survival.Keywords: non-small cell lung cancer, tumor volume, tumor burden, checkpoint inhibitors