Abstract 1774P
Background
Torque teno virus (TTV) is an apathogenic non-enveloped, circular single strand DNA virus and is used as a marker for the immune suppression status after solid organ transplantation. We investigated the role of TTV as possible marker for monitoring the immune function and changes in metastatic solid cancer patients during systemic therapies.
Methods
TTV level quantification was performed by polymerase chain reaction of full blood samples from newly-diagnosed therapy-naïve metastatic solid cancer patients before the first application of systemic therapy and at the following re-staging after 1-4 months. Systemic inflammation markers (neutrophil-to-lymphocyte ratio, leucocyte-to-lymphocyte ratio, platelet-to-lymphocyte ratio, monocyte-to-lymphocyte ratio) were obtained.
Results
71 patients (31/71, 43.7% females; 40/71, 56.3% males) with a median age of 64 years (range 27-89) with longitudinal TTV levels at baseline (BL) and the following re-staging were included in the analyses. The most common tumor entities included lung cancer (27/7; 38.0%), pancreatic cancer (9/71; 12.7%), sarcomas (7/71; 9.9%) and renal cell carcinoma (5/71; 7.0%). TTV levels at BL were not associated with age or cancer type (p>0.05). BL TTV levels were numerically higher in patients achieving a therapy response (median TTV level 3.5E+5) compared to patients showing disease progression at the following re-staging (median TTV level 1.2E+5; Mann-Whitney U test, p=0.071). There was no association of BL TTV levels with BL systemic inflammation markers (p>0.05). Thirty-one/71 (43.7%) patients showed a significant change (±1 log level) of TTV levels during systemic therapy (6/31, 19.4% patients with significant increase; 25/31, 80.6% patients with significant decrease). Increase or decrease of TTV levels was not associated with type of systemic therapy, therapy response nor with change of systemic inflammation markers (p>0.05).
Conclusions
Significant changes of TTV levels could be detected in a high portion of our cohort of advanced solid cancer patients under systemic therapy. Further longitudinal observation is warranted in order to specify the role of TTV levels as potential new immunological marker in cancer patients.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Financial support by the Austrian Federal Ministry for Digital and Economic Affairs, the National Foundation for Research, Technology and Development and the Christian Doppler Research Association.
Disclosure
A.M. Starzer: Financial Interests, Personal, Other, Travel support: PharmaMar. M. Preusser: Financial Interests, Personal, Advisory Board: Bayer; Financial Interests, Personal, Advisory Board: BMS; Financial Interests, Personal, Advisory Board: Novartis; Financial Interests, Personal, Advisory Board: Gerson Lehrman Group; Financial Interests, Personal, Advisory Board: CMC Contrast; Financial Interests, Personal, Advisory Board: GlaxoSmithKline; Financial Interests, Personal, Advisory Board: Mundipharma; Financial Interests, Personal, Advisory Board: Roche; Financial Interests, Personal, Advisory Board: BMJ Journals; Financial Interests, Personal, Advisory Board: MedMedia; Financial Interests, Personal, Advisory Board: AstraZeneca; Financial Interests, Personal, Advisory Board: AbbVie; Financial Interests, Personal, Advisory Board: Lilly; Financial Interests, Personal, Advisory Board: Medahead; Financial Interests, Personal, Advisory Board: Daiichi Sankyo; Financial Interests, Personal, Advisory Board: Sanofi; Financial Interests, Personal, Advisory Board: Merck Sharp & Dome; Financial Interests, Personal, Advisory Board: Tocagen; Financial Interests, Institutional, Sponsor/Funding: Böhringer-Ingelheim; Financial Interests, Institutional, Sponsor/Funding: BMS; Financial Interests, Institutional, Sponsor/Funding: Roche; Financial Interests, Institutional, Sponsor/Funding: Daiichi Sankyo; Financial Interests, Institutional, Sponsor/Funding: Merck Sharp & Dome; Financial Interests, Institutional, Sponsor/Funding: Novocure; Financial Interests, Institutional, Sponsor/Funding: GlaxoSmithKline; Financial Interests, Institutional, Sponsor/Funding: AbbVie. A.S. Berghoff: Financial Interests, Institutional, Research Grant: Daiichi Sankyo; Financial Interests, Institutional, Research Grant: Roche; Financial Interests, Personal, Advisory Board: Roche; Financial Interests, Personal, Advisory Board: BMS; Financial Interests, Personal, Advisory Board: Merck; Financial Interests, Personal, Advisory Board: Daiichi Sankyo; Financial Interests, Personal, Other, Travel support: Roche; Financial Interests, Personal, Other, Travel support: Amgen; Financial Interests, Personal, Other, Travel support: Daiichi Sankyo; Financial Interests, Personal, Other, Travel support: AbbVie. All other authors have declared no conflicts of interest.