“High Tumor Burden” in Metastatic Non-Small Cell Lung Cancer: Defining the Concept

Abstract

Purpose

Identifying patient characteristics that define a worse disease prognosis or “high tumor burden” (HTB) status is essential for clinical decision-making and treatment selection in metastatic non-small cell lung cancer (mNSCLC). We aimed to define this concept based on the experience of oncologists in clinical practice.

Patients and Methods

A representative sample of Spanish experts was selected and asked to complete an online survey regarding the definition of HTB according to their personal experience.

Results

HTB was identified by the oncologists (N = 81) as one of the principle factors influencing first-line treatment decision-making. According to the experts, HTB is mainly defined by the number of metastatic lesions (n = 45, 56%), location (n = 34, 42%), tumor size (sum of diameters of target lesions; n = 26, 32%) and liver involvement (n = 24, 30). High lactate dehydrogenase (LDH) levels were also associated with HTB. Almost half of respondents (n = 33, 41%) believed that one metastatic lesion was sufficient to consider a patient as presenting HTB, 72% (n = 58) considered that two were necessary and 99% (n = 80) three. Liver (n = 76, 100%) followed by brain (n = 65, 86%) were the main metastatic sites associated with HTB. Tumor size ranging from 6 cm to 10 cm as well as high LDH levels (three times the upper limit) defined the concept for 82% (n = 62) and 100% (n = 76) of oncologists, respectively.

Conclusion

In the real-world setting, according to experts, HTB is defined by the number of metastatic lesions, location of metastases, tumor size and by high LDH levels. Given the relevance of this concept, efforts should be made to unify its definition and to further explore its potential as a prognostic factor for mNSCLC patients.

Keywords:

• non-small cell lung cancer
• “high tumor burden”
• number of metastases
• tumor size
• metastatic locations
• lactate dehydrogenase

Acknowledgments

The authors would like to thank Dr. Almudena Fuster-Matanzo from Statistics Consulting S.L. (Valencia) for providing scientific support and medical writing services. The abstract of this paper was presented at the 2020 World Conference on Lung Cancer as a poster presentation with interim findings. The poster’s abstract was published in ‘Poster Abstracts’ in Journal of Thoracic Oncology (2021), Vol. 16 No. 3S: S521-S522: [https://www.jto.org/article/S1556-0864(21)00961-8/fulltext#secsectitle0020].

Disclosure

O.H.G. reports advisory and consultancy honoraria from Roche, AstraZeneca, Amgen, Boehringer and Sanofi, speaker honoraria from Roche, Merck, Bristol-Myers Squibb, AstraZeneca, Pfizer and Amgen, as well as travel/accommodation/expenses support from Roche, Merck, and AstraZeneca. A.M.P reports advisory/consultancy, speaker´s honoraria, and/or travel/accommodation expenses from Roche, MSD, and BMS. A-L.O.G. reports advisory and consultancy honoraria from Roche, Merck, Bristol-Myers Squibb and Boehringer, speaker honoraria from Roche, Merck, Bristol-Myers Squibb and Boehringer, as well as travel/accommodation/expenses support from Roche, Merck, and Bristol-Myers Squibb. L.V. reports advisory and consultancy honoraria from Roche, speaker honoraria from Roche and Bristol-Myers Squibb, research grant funding from AstraZeneca, as well as travel/accommodation/expenses support from Merck, Pfizer and Boehringer. D.P.P., P.R-G. and L.S.C-A. were full-time employees of Roche Farma S.A. at the time the survey was conducted. The authors report no other conflicts of interest in this work.