KTP Laser Treatment of Early Glottic Cancer: A Multi-Institutional Retrospective Study

Abstract

<jats:sec><jats:title>Objectives:</jats:title><jats:p> The primary objectives were to report oncologic outcomes of transoral laser microsurgery with potassium-titanyl-phosphate (KTP) laser (TLM-KTP) ablation of early glottic cancer (EGC). The secondary objectives were to report vocal outcomes and to analyze factors that might influence outcomes. </jats:p></jats:sec><jats:sec><jats:title>Methods:</jats:title><jats:p> A multi-institutional, retrospective analysis of consecutive patients treated for T1 or T2 glottic squamous cell carcinoma undergoing TLM-KTP ablation with at least 2 years of follow-up was performed. Patients with prior radiation or surgery for laryngeal disease were excluded. </jats:p></jats:sec><jats:sec><jats:title>Primary outcome measures included:</jats:title><jats:p> surgical failures requiring radiation or laryngectomy, disease-specific survival (DSS), and overall survival (OS). Secondary outcome measures included: pre- and postoperative Voice Handicap Index-10 (VHI-10) scores. The effects of smoking status, stage, and anterior commissure involvement on outcomes were analyzed. </jats:p></jats:sec><jats:sec><jats:title>Results:</jats:title><jats:p> Overall 88 patients met inclusion criteria (83% male, 79.5% current or former smokers). Mean age was 68 (standard deviation (SD): 12). Mean follow-up was 39.5 months (SD: 15.3). Staging included 50 T1a, 21 T1b, and 20 T2 tumors, including three metachronous second primaries. Radiation and/or laryngectomy avoidance was achieved in 87/88 (98.9%) of patients, inclusive of 24 patients requiring KTP re-treatments. Two patients had biopsy-proven recurrence (2.3%), but only 21 of 24 re-treated patients received a formal biopsy. No patients died from laryngeal cancer. DSS and OS were 100% and 92.3%, respectively. The mean VHI-10 scores were 19.3 preoperatively, 3.8 at 6-months postop, and 3.8 at 2-years postop. Smokers had a longer interval to re-treatment ( P = .03), patients with T2 lesions had a shorter interval to re-treatment (0.02), and patients with T2 lesions presented with worse initial VHI-10 scores (0.002). </jats:p></jats:sec><jats:sec><jats:title>Conclusions:</jats:title><jats:p> A multi-institutional, retrospective case series of TLM-KTP ablation of EGC demonstrated excellent oncologic outcomes when close surveillance and proactive re-treatments were utilized. Disease-specific survival, overall survival, and vocal function were excellent. Additional studies are necessary to further analyze the merits and risks of this treatment approach. </jats:p></jats:sec>

Outcomes of KTP Laser Ablation in Glottic Neoplasms: A Systematic Review and Meta‐Analysis

“…32 Similarly, Parker et al reported a very low recurrence rate of 2% following KTP. 28 These findings indicate that KTP is associated with a similar recurrence rate to radiotherapy and CO 2 .…”

“…The final meta-analysis included eight studies (Figure 1). 6,[27][28][29][30][31][32][33] A total of 342 patients underwent KTP laser ablation within the included studies. All the included studies were performed between 2013 and 2022.…”

Lasers and Robots: Recent Developments in Transoral Laser and Transoral Robotic Surgery

“…In addition to the use of CO2 gas laser, solid-state diode lasers have also been investigated for their potential use in transoral surgery. 11,[13][14][15][16][17] The limitations of CO2 laser, namely field of view constraints, narrow penetration, and cost, prompted the investigation of using other lasers like KTP (potassium titanyl phosphate) and dual-wavelength optic fiber laser. Compared to CO2 laser, KTP laser has been found to have superior coagulative capability and greater penetration.…”

Soft robotic manipulator for intraoperative MRI-guided transoral laser microsurgery

“…Laser ablation in glottic cancers with ultranarrow margins has been shown to be effective in preserving vocal function without the need for further adjuvant radiotherapy ( 5 ). This can be used even for bulky tumors that are early stage, with the advantage of minimal thermal spread to the surrounding normal tissue ( 6 ). Now, with the human papilloma virus–associated oropharyngeal cancer epidemic that is associated with improved outcomes and where narrower margins for resections are needed, the use of laser for resections has been shown to improve pain scores and to reduce hospital stay and time to oral feeding when compared with the use of traditional cautery ( 7 ).…”