3 Results
3.1 Study selection
The initial literature search yielded a total of 240 articles. Studies
that were duplicated were excluded. Four articles were also excluded
based on their titles and abstracts. The remaining 54 potentially
eligible studies were retrieved for a careful review of the full texts.
Among them, studies without a control group, review articles, studies
with the same database, studies including non-laryngeal cancer patients,
studies with unclear inclusion criteria and studies not written in
English were excluded from the analysis. Finally, 7 articles were
included in this review 10-16. A flow diagram
describing the process involved in study identification and
inclusion/exclusion is shown in Figure 1 . eTable 1 in
the Supplement summarizes the literature search process and the
keywords used.
3.2 Demographics
Table 1 lists the basic demographics of patients from the 7
articles, including two randomized studies and 5 nonrandomized studies.
The pooled prevalences of preoperative tracheostomy and radiotherapy
were both significantly higher in the SC group (P =0.04 andP =0.00, respectively). The bias assessment for each study is
described in eTable 2 and eTable 3 in the Supplement .
3.3 Outcomes
3.3.1 Operative time
Four of the included studies evaluated the operative time (total
laryngectomy with/without neck dissection) of both procedures11,12,14,15. Two of these 4 studies included only
cases of isolated total laryngectomy (without neck dissection)12,14. The pooled results of 4 studies showed that the
operative time was lower in the SC group (MD, -63.2; 95% confidence
interval [CI], -106.0 to -20.4), and a decrease in operative time by
63.2 minutes was observed in the SC group (Figure 2a)11,12,14,15. Subgroup analysis including the 2 studies
without neck dissection also showed that the operative time was lower in
the SC group (MD, -45.9; 95% CI, -64.2 to -27.6) with a decrease of
45.9 minutes12,14. (Figure 2b).
3.3.2 PCF
All of the included studies recorded the incidence of postoperative PCF
in both groups. In the present study, the incidence rates of PCF were
13.7% (28/204) and 27.2% (90/331) in the SC and MC groups,
respectively. The pooled analysis showed that the PCF rate was lower in
the SC group (OR = 0.38; 95% CI, 0.18-0.83; P = 0.016).(Figure 3).
3.3.3 Length of hospital stay
Three of the included studies recorded the length of hospital stay in
the two groups. The pooled analysis demonstrated that the length of
hospital stay after TL was approximately 2.9 days shorter in the SC
group than in the MC group (MD, -2.9; 95% CI, -5.6 to -0.1).
(Figure 4).
3.3.4 Postoperative surgical site infection
Two of the included studies recorded the incidence of postoperative
surgical site infection in both groups. The pooled analysis showed no
significant difference between the SC and MC groups regarding the rate
of postoperative surgical site infection (OR = 0.41; 95% CI,
0.02-8.73; P = 0.565). (Figure 5).
3.4 Publication Bias
Funnel plots and the results of heterogeneity tests are presented ineFigure 1 in theSupplement . The plots of different parameters are generally
symmetrical, suggesting no obvious publication bias. The results of the
Egger intercept test also indicated no apparent publication bias.