Zapping Vocal-Cord Cancer With Lasers Proven Effective In Long-Term Study

By Chuck Seegert, Ph.D.

A pioneering laser treatment for early vocal-cord cancer has shown promise as a long-term cure for the disease. In addition to being as effective as traditional approaches at curing tumors, the treatment developed at Massachusetts General Hospital is also able to spare the patient’s vocal cords and ability to speak.

Vocal-cord tumors, which are sometimes referred to as glottic cancers, can be found early in their progression because changes to the voice occur. The treatment of these tumors enjoys a relatively high success rate using therapies like vocal-cord stripping, radiation therapy, and laser treatment. Though successful treatment of the cancer can be achieved with these methods, a patient may experience a change in voice or, in the worst-case scenario, a loss of their ability to speak.  

To overcome this shortcoming, researchers at Massachusetts General Hospital (MGH) developed a more refined laser treatment, according to a recent press release from the American Cancer Society. The success of the new treatment is based on a green-light potassium-titanyl-phosphate (KTP) laser, which has been championed for this use by Steven Zeitels, M.D., the director of the MGH Voice Center.

The KTP laser works through a process called photoangiolysis and essentially destroys concentrations of blood vessels. Originally, it was used to treat vascular malformations in infant patients’ delicate skin, according to the press release. Vocal-cord tumors also have a denser blood supply, so the laser can target that tissue specifically. This saves the underlying vocal-cord tissue, which is less vascular.

Traditional laser treatments can damage too much of the underlying vocal-cord tissue, because they do not discriminate between healthy and diseased tissue, according to the press release. A similar problem exists with the use of radiation therapy, which can damage one or both of the vocal cords. Additionally, radiation therapy is thought to be a single-shot treatment, and it is desirable to save it as an option in the event that the cancer progresses and becomes more serious.

This most recent analysis of the KTP treatment method has examined its oncologic efficacy, or how well it prevents long-term recurrence of the disease, according to a recent study published by Dr. Zeitels and his team in the Annals of Otology, Rhinology & Laryngology. After an average of 53 months, the disease was controlled in 96 percent of patients with early stage tumors and 80 percent of patients with more advanced tumors. Of the 117 patients involved in the study, only 10 were subject to recurrence and subsequently treated with radiation therapy. Of these relapses, five were successfully treated, while the other five expired.

Another benefit to KTP laser treatment is that it allows biopsies to be collected in the same procedure as the treatment, according to the press release. Radiotherapy requires a biopsy prior to the procedure to help delineate the extent and location of the tumor.

While this study was focused on the oncologic efficacy, previous studies have been published by Dr. Zeitels and his team related to the KTP laser approach. For example, a study was published that focused on the ability of the KTP laser to spare a patient’s voice, according to an article published on Med Device Online.