The first long-term study of a pioneering endoscopic laser treatment for early vocal-cord cancer, developed at the MGH and previously shown to provide optimal voice outcomes, finds that it is as successful as traditional approaches in curing patients’ tumors while avoiding the damage to vocal quality caused by radiotherapy or by conventional laser or cold-instrument surgery. The report in the December Annals of Otology, Rhinology & Laryngology describes results for the first 117 patients treated for vocal-cord cancer with the green-light potassium-titanyl-phosphate (KTP) laser by Steven Zeitels, MD, director of the MGH Voice Center and developer of the procedure.
“Use of the KTP laser, which eradicates blood vessels in a process called photoangiolysis, was conceived to treat vascular malformations in infants’ delicate skin; but we have demonstrated that this specialized laser is especially effective in treating vocal-cord cancer,” says Zeitels. “These tumors have a denser blood supply than the underlying vocal-cord tissue, preservation of which is necessary to retain optimal vocal quality. As reported in this paper, our success in curing patients with small tumors with the angiolytic KTP laser is extremely high and very high for those with mid-sized tumors.
“Since radiation can damage the non-cancerous tissue of one or both vocal cords and conventional laser surgery destroys more delicate vocal tissue than is necessary, KTP laser treatment typically produces better vocal results while being more cost-effective,” he adds. “And a key issue when selecting a treatment for vocal-cord cancer is that radiation is considered to be a single-use treatment. So it is important to preserve the option of radiotherapy for treating future, more substantial cancers, the development of which is not uncommon.”
Zeitels first reported the use of the yellow-light, pulsed-dye laser to treat early vocal-cord cancer 10 years ago, and in 2006 he and his colleagues introduced treatment with the more precise green-light KTP laser. The current paper describes results for 117 patients treated with the green-light KTP laser between 2006 and 2010. Some had cancer invading both vocal cords, but none had received radiotherapy before the laser treatment. Of the 82 treated patients with small tumors, 96 percent (79 of 82) have had no recurrence more than three years after treatment, and 80 percent (28 of 35) of those with mid-size tumors also have had no recurrence. Among the 10 patients whose tumors did recur, radiation treatment was successful in controlling the cancer in 5. Overall 96 percent – 112 of 117 patients – of those treated have survived an average of almost four and a half years and are cancer-free without loss of their larynx. Since 2010, more than 75 additional patients have received pulsed-KTP laser treatment for early vocal-cord cancer at the MGH.
Read more articles from the 12/12/14 Hotline issue.