The long-term oncological and functional outcomes of T2b and selected T3 glottic cancer treated by OPHL Type IIa and its modified version OPHL mType IIa, in which the upper borders of both thyroid cartilage laminas were preserved, were investigated, compared to each other and discussed in relation to other.
Oncological outcomes
In our series, the whole OPHL group achieved overall survival, disease specific survival, local control rate and organ preservation rate 89.71 %. Superior oncological outcomes, mainly measured by local control rates ranged in literature from 79.1 to 93.94 % and were confirmed by numerous authors [
13‐
20] with highest score 97 % given by Laudadio et al. [
21].
Treatment modalities available for T2 glottic cancer include a wide range of open surgical techniques, with vertical partial laryngectomy (VPL) or frontal anterior laryngectomy (FA) among them. Zhang et al. [
22] found a significantly lower post-operative local recurrence rate in SCPL-CHEP than in VPL groups (2.6 vs. 17.8 %,
p = 0.033). In contrast, favorable oncological results for vertical procedures presented Hartl et al. [
23] with local control rate of 83 % for tumors with cartilage invasion and 94 % for those without invasion; difference was not significant, which was probably due to systematic resection of thyroid cartilage. Bakhos et al. [
14] compared FA laryngectomy and CHEP, which is used more often when there was contra-lateral vocal fold spread; 5-year survival rate was 95 and 85 %, respectively, local tumor control was obtained in 87 in 83 %, respectively, but CHEP resulted in better postoperative outcomes. Wen et al. [
4] presented the SCPL modalities: CTP and CHEP with recurrence rates 13 and 15 %, respectively.
Predictors of local control and survival were presented by Gallo et al. [
16] in 253 samples. Univariate and multivariate analyses showed that a positive resection margin was the only important predictor of local control. A report on 291 patients by Page et al. [
17] estimated the local (laryngeal) control rate to be 93.94 % and regional (cervical lymph node) control rate to be 92.05 %; in multivariate analysis, the occurrence of a second non-ENT cancer, distant metastases and margins involvement were reliable to mortality. The significantly higher frequency of local recurrence among women in OPHL, in our opinion, was related to smaller dimensions of the female larynx, compromising the efforts of the surgeon to obtain free margins.
Functional outcomes
Early outcomes: in our study higher rates of the swallowing problems were connected with OPHL Type IIa than with mType IIa. The time to nasogastric tube removal was an important outcome measure in the early post-operative period. In the literature this varied notably from 3 to 134 days [
24]. In our sample the median time of nasogastric tube removal was 12 days (11 days for OPHL mType IIa). The swallowing rehabilitation was conducted during the hospital stay, and patients were discharged when thick liquids could be consumed.
Late outcomes are dyspnea, aspiration and swallowing problems [
25‐
27]. In our Department the planned tracheotomy was not included in our operating schedule. Temporary tracheotomy was needed in 34 patients but 14/30 in OPHL Type IIa and 2/4 in OPHL mType IIa were decannulated in time. Lucioni et al. [
28] noticed that 8 % of 225 patients had laryngeal stenosis; all underwent CO2 laser one or two times, decannulation was possible in all patients except in one; authors concluded that the only reasonable contra-indication to CO2 laser could be a cranio-caudal length of the laryngeal stenotic tract longer than 1 cm. In the own 28 cases (24 OPHL Type IIa, 4 OPHL mType IIa), the CO2 laser was used to widen the neoglottis. In two females tracheotomy was needed in 2 and 6 months postoperatively but no attempts to widen the airway lumen were undertaken. Finally, 16/80 (20 %) OPHL Type IIa and 2/27 (7.4 %) OPHL mType IIa patients required permanent tracheotomy.
The compensation mechanism for swallowing after SCPL is antero-medial rotation of the remaining arytenoids that make contact with epiglottis in concordance with flexion of epiglottis, following posterior tongue movement [
29,
30]. Crico-arytenoid unit preservation (cricoid cartilage and at least one mobile arytenoid cartilage) constitutes the most important condition of the effective swallowing rehabilitation. Including the arytenoids into resection margin, as in extended SCPL with both arytenoids excision, presented by Rifai et al. [
31] was feasible, but active swallowing rehabilitation was principally needed. Alicandri-Ciuffiei et al. [
32] sampled 106 patients and found the non-typical conformations and anomalous positioning of the epiglottis, and involvement of the lateral pharyngeal wall in the sphincteric and vibratory function of the neoglottis. On the other hand, complete epiglottis prolapse, which obstructed the neoglottis was described in three cases by Nakayama et al. [
33]. In our study seven patients had one arytenoid resected; and it was combined with the transverse formation of the neoglottis and mucosal fold prolapse in five cases.
Deglutition is the main cause of morbidity in open partial laryngectomies, but the results reported in literature have been very diverse. In Farrag et al. [
34], all 24 patients had a tracheostomy and percutaneous endoscopic gastrostomy (PEG) tube placement performed at the time of SCPL, with a median time to decannulation and PEG tube removal of 37 and 70 days, respectively. In 18 patients, Clayburgh et al. [
35] showed similarly bad results, with an average decannulation time of 27.4 days, feeding tube removal at 87.9 days postoperatively and 67 % of patients tolerated an unrestricted diet at follow-up. Oysu et al. [
36] compared the near total laryngectomy and CHEP technique; mean decannulation time was 27 and 20 days, respectively, and average nasogastric tubes removal at 23 and 17 days, respectively. In contrast to the presented above unsatisfactory results, Simonelli et al. [
37] based on large sample (
n = 116), concluded that patients with functional deglutition after SCPL showed a mild and well-tolerated degree of chronic aspiration and did not require limited oral intake. Nakayama et al. [
20] observed that swallowing function (ability to eat in public) was acquired in 28/30 (93 %) irradiated and 39/43 (91 %) non-irradiated patients. Bussi et al. [
38] removed the nasogastric tube in CHEP and CHP groups after an average 16 days, and good deglutition was recorded in 41 of the 44 cases (93.18 %) and adequate deglutition in the remaining 3 cases. In our series, unrestricted diet at 1 month was achieved by all of patients except one, in whom gastrostomy was needed; social eating declared 54/80 (67.5 %) CHEP and 25/27 (92.6 %) mCTP patients. The mCTP technique was shown to be valuable because it did not disturb oral intake.
Voice
Primary RT seems to be the voice preserving treatment modality [
39] but less effective oncologically. On the other hand, all manipulations in AC region worsen the glottis closure. Wen et al. [
4] reported that SCPL-CTP group had significantly lower VHI scores, higher maximum phonation time and improved glottis closure than the SCPL-CHEP group. In the samples of Oysu et al. [
36], the mean VHI score was 55.58 in the CHEP group and 52.78 in the near total laryngectomy group. The detailed voice outcomes of 250 SCPL patients operated on in our Department have been presented elsewhere [
40]. In the present study, the quality of voice after treatment was analyzed by means of the physical subscale of the VHI and MPT examination. The VHI results differ between the examined cohorts: 31/120 in CHEP and 46/120 in mCTP were found, and MPT achieved 8 and 10.1 s, respectively. The mCTP technique was superior to CHEP in terms of voice quality.