Advancing Education, Research, and Quality of Care for the Head and Neck oncology patient.
Introduction: Oral leukoplakia describes a variety of conditions ranging from isolated dysplastic lesions to proliferating verrucous leukoplakia (PVL), a rare but aggressive disease that is challenging to manage due to its high risk of recurrence and malignant conversion. There is currently no clearly defined protocol or definitive treatment for oral leukoplakia despite risks of progression to aggressive oral pathology such as squamous cell carcinoma (SCC). This retrospective study investigates the efficacy of potassium-titanyl-phosphate (KTP) laser used to treat oral leukoplakia at a tertiary care center. The endpoints of interest include clinical response, patient-reported symptoms, and risk factors in patients treated with KTP laser therapy.
Methods: A retrospective review of patients who underwent KTP laser treatment for leukoplakia was completed. All patients who received KTP laser as either first-line or adjunct treatment post-surgical excision for oral leukoplakia or an index cancer were included (n=17). Patient demographic information, past medical history, and treatment course data were collected. All patient-reported symptoms were detailed. Descriptive statistics were summarized, and Fisher’s exact and Wilcoxon rank-sum tests were performed.
Results: The average number of KTP laser sessions was 1.82. Among the cohort, 35% (n=6) had resolution or regression of leukoplakia after KTP laser therapy that required no further intervention during the follow up period (516 ± 332 days). An additional 12% (n=2) had near-complete resolution, but underwent alternative treatment for areas of persistence. Initially, an additional 35% (n=6) of patients showed resolution or regression with KTP laser therapy but later demonstrated recurrence. Another subset of patients showed persistence of leukoplakia despite KTP laser therapy and underwent alternative treatment in the form of cryotherapy (18%, n=3).
Roughly two-thirds of patients had biopsy-proven PVL (n=11). There was a statistically significant difference in the rates of resolution between patients with PVL and those without PVL (Fisher’s exact test, p = 0.029; 0% in PVL patients (0/11) vs 50% in non-PVL patients (3/6)). There was no statistically significant difference in the time to recurrence between the cohorts (Wilcoxon rank-sum test, p= 0.355). During the study period, no cases of leukoplakia progressed to SCC. Among patients with previous SCC (n=5), none developed a second primary malignancy.
There were no major adverse events related to KTP laser therapy, defined as return to office for bleeding, intolerance of oral intake, or emergency room visit. Minor adverse events including self-limited pain (n=7) and mild bleeding (n=1) were reported. No patients reported symptoms beyond two weeks post-KTP laser therapy.
Conclusion: KTP laser therapy is a promising novel technique for the management of oral leukoplakia. The recurrence rate (35%) is one of the lowest reported among leukoplakia treatment modalities. No cases of oral leukoplakia progressed to SCC during the study period. There were no major adverse events related to KTP laser therapy, and the symptoms reported were mild and self-limited. A subset of patients (18%) showed minimal response to KTP laser therapy warranting further investigation. Further long-term prospective clinical studies are needed to validate KTP laser therapy as a definitive treatment modality for oral leukoplakia.