The first long-term study of a pioneering endoscopic laser treatment for early vocal cord cancer, previously shown to provide optimal voice outcomes, finds that it is as successful as traditional approaches in curing patients’ tumors. Also, it avoids the damage to vocal quality caused by radiotherapy or by conventional laser or cold-instrument surgery.
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 Massachusetts General Hospital (MGH) Voice Center and developer of the procedure, were published in Annals of Otology, Rhinology & Laryngology (2014; doi:10.1177/0003489414538936).
“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,” said 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 noncancerous 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.
Zeitels added that it is important to preserve the option of radiotherapy for treating future, more substantial cancers, since it is not uncommon to develop these.
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% (79 of 82) have had no recurrence more than 3 years after treatment, and 80% (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 five. Overall, 96% (112 of 117 patients) of those treated have survived an average of almost 4.5 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 MGH. Zeitels recently treated a 13-year-old boy with vocal cord cancer, a rare condition in a person so young. The first child to receive the KTP laser cancer treatment, he was referred to Zeitels after cancer was discovered in a biopsy of what were originally believed to be benign human papillomavirus (HPV) warts. While in only the first months after treatment for tumors involving both vocal cords, the youth’s voice has returned to near normal for his sex and age.
Another important aspect of the green-light KTP laser approach, Zeitels added, is that biopsy and treatment of patients whose cancer involves a single vocal cord usually can be accomplished in the same procedure, whereas radiotherapy requires a prior biopsy to determine the extent and location of the tumor, followed by daily radiation treatments over approximately 6 weeks.