[Beyond the Buzz: Tumor Treating Fields for Cancer]

Overview

Tumor Treating Fields (TTFields) are a non-invasive cancer therapy that uses low-intensity, alternating electric fields to disrupt cancer cell division. Approved by the FDA for several oncology indications, TTFields are being investigated for additional cancer types and treatment contexts through ongoing trials.

FDA-Approved Indications

Ovarian cancer (recurrent, during certain clinical settings)
Glioblastoma (new and recurrent)
Malignant pleural mesothelioma
Pancreatic cancer (specific settings in trials)

These approvals reflect TTFields’ mechanism of interfering with mitotic spindle formation and septation during cell division, potentially slowing tumor growth while minimizing systemic toxicity.

Mechanism of Action

TTFields create disruptive electric fields that target highly dividing cells.
The fields interfere with microtubule polymerization and cytokinesis, leading to mitotic arrest and cell death in tumor cells.
Normal, non-dividing cells are less affected, contributing to a favorable tolerability profile.

Clinical Evidence and Trials

Historical and contemporary studies show improvements in progression-free survival and overall survival in select tumor types when TTFields are combined with standard therapies (e.g., chemotherapy, immunotherapy).
Trials continue to evaluate TTFields in:
- Brain tumors beyond glioblastoma
- Non-small cell lung cancer (NSCLC)
- Other solid tumors
Combination strategies aim to enhance efficacy while preserving quality of life.

Practical Considerations

TTFields therapy requires patients to wear a transducer array system on the skin over the tumor site, connected to a portable medical device.
Treatment is typically administered for many hours daily, integrated with other anticancer therapies.
Common adverse effects are localized skin irritation at the array site; systemic toxicity is generally lower than with some chemotherapy regimens.

Limitations and Future Directions

Not all tumor types respond to TTFields, and effectiveness varies by cancer biology and treatment context.
Ongoing research explores optimal dosing schedules, combination partners (chemotherapy, immunotherapy), and new indications.
As evidence accumulates, TTFields might become a broader component of multimodal cancer care for selected patients.

Author's Summary

TTFields offer a non-invasive, targeted approach to slow tumor growth in certain cancers, with a growing but cautious evidence base supporting broader use in combination therapies.

Medscape — 2025-12-01