FLEX October 2023

15314995, 2023, 8, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/lary.30547 by Wake Forest Univesity, Wiley Online Library on [18/08/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License

after further sensitivity analyses, so the random-effects model was employed (Figure 3A). VHI within 6 months and after one-year follow up. The overall mean reduction from baseline in VHI attributed to KTP in the single-arm meta-analysis was 6.15 (95% CI [3.08, 9.22]; n = 108 patients) and 2.25 (95% CI [ 1.56, 6.07]; n = 134 patients) within 6 months and after a one-year follow-up, respectively. Pooled analyses were heterogeneous ( I 2 = 83.12% and 93.8%) and heterogeneity did not resolve after further sensitivity analyses, so the random-effects model was employed (Figure 3B, C). DISCUSSION The effectiveness and safety of the KTP laser for the management of early glottic neoplasms have gained much attention since its fi rst application in 2003. Nonetheless, little is still known regarding the performance of the KTP laser compared to standard modalities. This systematic review and meta-analysis found that the KTP laser had a clinically meaningful outcomes, such as overall survival, disease-free survival, and recurrence rate, which are com parable to the previously reported outcomes of standard modalities (CO 2 and radiotherapy). The KTP laser tech niques resulted in improved short-term voice outcomes. The overall survival and disease-free rates for patients treated with KTP were 90.7% and 98.5%, respec tively. In their study, Ahmed et al. stated that the KTP laser led to a disease-free and overall survival of 88% and 98%, respectively. 33 Likewise, the disease-free rate in Barbu et al. was 80% in patients who received KTP, with no profound complications such as impaired swallowing function or airway obstruction. In addition, they found no signi fi cant difference in postoperative healing rates after CO 2 or KTP laser usage. Both groups had a comparable risk of limited thyroid cartilage necrosis and substantial granulation. 6 In the study by Nouraei et al., the fi ve-year overall survival for patients on KTP was 56%. For dyspla sia and malignancy, KTP-only disease control rates were 87.1% and 53.5%, respectively, during 5 years. The only independent risk factor for KTP treatment failure was a dif fi cult direct laryngoscopy. They further highlighted that the laryngeal preservation in patients who received KTP was 100%, 31 which is in line with the 97.5% laryn geal preservation rate for early-stage glottic malignancy and carcinoma in situ with RT. Similarly, Zeitels et al. reported a 99% and 89% larynx preservation and survival in patients treated with KTP for T1 and T2 disease, respectively. Disease control was achieved in 96% of the patients with T1 disease. 29 In our study, the pooled estimate of KTP recurrence rates 7.7%. Ahmed et al. conducted a retrospective study on patients with T1 glottic carcinoma. 33 Their fi ndings showed no signi fi cant difference between the KTP and external beam RT regarding the six-month recurrence rate ( P = .77). Moreover, there was no signi fi cant differ ence between the two groups regarding the number of days until recurrence ( P = .27). Early glottic carcinoma recurrence has been linked to anterior commissure involvement 34 – 37 ; however, Ahmed et al. found no

Study complete follow up or - small number lost Ahmed 33 Yes Yes Yes Yes Yes Yes Yes Yes Yes 9 Score Representativeness of the exposed same community as the exposed cohort assessment or records for outcomes to occur Barbu 6 No No Yes Yes Yes No Yes Yes No 5

Parker 28 Yes No Yes Yes Yes Yes Yes Yes No 7

Zeitels 29 Yes No Yes Yes No No Yes Yes Yes 6

Murono 27 No No Yes Yes No No Yes Yes Yes 5

Nouraei 31 No Yes Yes Yes Yes Yes Yes Yes No 7

follow up of

cohorts with

Adequacy of

Selection Comparability Outcome

Follow-up

long enough

outcome through independent

Assessment of

TABLE III. Newcastle-Ottawa Quality Assessment Scale for Cohort Studies * Demonstration that outcome of interest was not present at start of study Comparability of cohorts based on the design or analysis (e.g., comparative statistical analysis of primary outcome) Comparability for any additional factor (e.g., comparative statistical analysis of secondary outcome)

exposure through secure record (e.g., surgical records)

* Scores ≥ seven implicate a high-quality article, and < fi ve indicate low-quality research.

Ascertainment of

Selection of the non-exposed

control from the

cohort population

Laryngoscope 133: August 2023

Suppah et al.: KTP in Glottic Neoplasms

1810