FLEX October 2023

259

Volume 90 Number 2 2014

Voice quality in early laryngeal cancer

Expert-rated voice quality

Table 2

Transoral laser surgery

Radiation therapy

P y

P *

P *

Measurement

Baseline

6 months

24 months

Baseline

6 months

24 months

Grade

1.61 (0.94) 1.30 (0.88) 1.35 (0.89) 0.61 (0.66) 0.96 (0.71)

1.78 (0.16) 1.13 (0.92) 1.48 (0.90) 0.75 (0.68) 0.83 (0.72)

1.61 (0.17) 1.26 (0.86) 1.52 (0.95) 0.74 (0.69) 0.78 (0.80)

.537 1.44 (0.92) .699 1.22 (0,73) .617 1.17 (0.79) .599 0.56 (0.51) .532 0.83 (0.92)

1.56 (0.18) 1.56 (0.92) 0.44 (0.62) 0.06 (0.24) 0.89 (0.68)

1.39 (0.19) 1.39 (0.61) 0.28 (0.58) 0.11 (0.32) 1.06 (0.80)

.614 .967 .284 .248

Roughness Breathiness

< .001

< .001

Asthenia

.001 .003

Strain .498 .288 The data are mean values (standard deviations) of the grade, roughness, breathiness, asthenia, and strain (GRBAS) scale used to assess perceptual voice quality. Each aspect of voice quality was scored from 0 to 3, the higher scores indicating worse voice quality. The baseline voice sample was not available from 1 patient in the radiation therapy group, the 6-month sample from 7 patients in the laser surgery group and from 2 patients assigned to radiation therapy, and the 24-month sample from 4 patients treated with laser surgery and from 5 treated with radiation therapy. * Change during the follow-up as compared with the baseline value within the treatment group (repeated-measures analysis of variance). y Difference between the treatment groups (repeated-measures analysis of variance).

correlated with the presence and extent of an irregular vocal cord chink at stroboscopy ( r Z 0.511, P Z .001), with an oval chink ( r Z 0.571, P < .001), and with otherwise incomplete glottal closure of the vocal cords ( r Z 0.565, P < .001).

overall voice quality achieved was roughly similar after the treatments, but patients treated with radiation therapy had less breathy voice, maintained better glottal closure, and experienced less inconvenience in their daily lives from their voice quality than those treated with TLS. In line with the absence of randomized trials in the literature, we found conducting of the current trial chal lenging, with accrual lasting for 10 years. We estimate that 80% of the eligible patients did not enter the study in the participating centers, creating a possibility for selection bias (6). We did our best to improve accrual, but the accrual rate remained low. We persisted with the study because we believe that a randomized trial, even a slowly accruing trial, allows more reliable evaluation of the treatments than nonrandomized cohort studies. A recent Cochrane review concluded that reliable con clusions regarding the quality of voice achieved with TLS and radiation therapy cannot be made in the absence of randomized trials (2). Several cohort studies conclude that radiation therapy leads to better voice quality, whereas others suggest that the overall voice quality is similar (2). Voice quality after TLS depends on several factors such as the surgeon’s experience and skill, tumor size, and site. We attempted to account for such factors by limiting the study to large referral hospitals and to small tumors. Voice breathiness (B) differed most clearly between the groups. Notably, breathiness improved after radiation therapy over the 2-year observation period, whereas no

Cancer recurrence and survival

Fifteen (48%) of the 31 patients assigned to TLS underwent 1 or more unscheduled laryngomicroscopies after treatment as compared with 6 (24%) of the 25 patients assigned to radiation therapy ( P Z .077; the data were missing for 1 patient assigned to radiation therapy). Three (10%) patients in the TLS group and 3 (12%) in the radiation therapy group had cancer recurrence during the 2-year follow-up period. One patient in the TLS group received a diagnosis of metastatic laryngeal cancer and died, and 1 had a second primary tumor in the contralateral vocal cord 1.5 years after entry into the study. None of the patients allocated to ra diation therapy experienced metastases.

Discussion

TLS and radiation therapy for early glottal carcinoma have been investigated in numerous prospective and retrospec tive cohort studies, but no randomized studies have been reported (1, 2). We found in this randomized study that the

Self-rated voice quality

Table 3

Transoral laser surgery

Radiation therapy

P y

P * Baseline

P *

Measurement

Baseline

6 months 24 months

6 months 24 months

Hoarseness

59.0 (19,0) 50.7 (28.9) 43.1 (27.1) .040 53.1 (22.0) 34.1 (24.3) 35.4 (26.7) .026 .144

Impact on everyday life 44.6 (26.5) 31.4 (25.9) 32.4 (25.3) .089 32.1 (25.7) 14.4 (18.8) 8.40 (9.3) .001 .007 The data are mean values (standard deviations) evaluated on a visual analogue scale (VAS) scored from 0 to 100. The higher scores indicate worse subjective impression of the quality of voice. The baseline VAS was missing from 5 patients in the laser surgery group and from 1 patient in the radiation therapy group, and the 6-month sample from 7 and 3 patients, and the 24-month sample from 6 and 8 patients, respectively. * Change during the follow-up as compared with the baseline value within the treatment group (repeated-measures analysis of variance). y Difference between the treatment groups (repeated-measures analysis of variance).