What Are Tumor Treating Fields?

Tumor treating fields (TTFields) are electrical fields that disrupt the division of cancer cells. In preclinical models of non-small cell lung cancer (NSCLC), the use of TTFields has been shown to improve response to the effects of chemotherapy and immune checkpoint inhibitors.1

How Do Tumor Treating Fields Work?

TTFields are delivered by a non-invasive wearable device. This device generates alternating electric fields that exert physical forces on the electrically charged parts of dividing cancer cells. This results in cancer cell death.2 

What Devices Delivering Tumor Treating Fields Are FDA-Approved?

There is currently one device approved by the FDA to use TTFields: 

  • Optune Lua® concurrent with PD-1/PD-L1 inhibitors or docetaxel is approved for adult patients with metastatic NSCLC who have progressed on or after a platinum-based regimen3 

What Are the Side Effects of Tumor Treating Fields?

Side effects of TTFields vary by patient. Some side effects include: 

  • Skin irritation
  • Skin ulcers
  • Pain in the muscles, bones, or joints
  • Fatigue
  • Anemia
  • Nausea
  • Diarrhea
  • Respiratory tract infection
  • Dyspnea (shortness of breath)
  • Leukopenia (low white blood cell count)

Tips for managing treatment-related side effects.

 

Updated April 4, 2025

REFERENCES

  1. Leal T, Kotecha R, Ramlau R, et al. Tumor treating fields therapy with standard systemic therapy versus standard systemic therapy alone in metastatic non-small-cell lung cancer following progression on or after platinum-based therapy (LUNAR): a randomised, open-label, pivotal phase 3 study. Lancet Oncol. www.thelancet.com/journals/lanonc/article/PIIS1470-2045(23)00344-3/abstract. Posted September 2023. Accessed April 3, 2025.
  2. ‌Sava J. FDA OKs Optune Lua for use with PD-1/PD-L1 inhibitors in metastatic NSCLC. Targeted Oncol. www.targetedonc.com/view/fda-oks-optune-lua-for-use-with-pd-1-pd-l1-inhibitors-in-metastatic-nsclc. Published October 16, 2024. Accessed April 3, 2025.
  3. Premarket Approval (PMA). FDA.gov. www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpma/pma.cfm?id=P230042. Published 2023. Accessed April 3, 2025.