184 / 220
Effect of adjuvant therapy on survival
In this cohort, patients either underwent surgery alone
(
n
5
26), surgery with postoperative radiotherapy (
n
5
89), or surgery with postoperative chemoradiotherapy (
n
5
143). In the remaining patients (
n
5
38), the data were
incomplete with regard to adjuvant therapy, and these
patients with missing data were excluded from the multi-
variable analysis.
Multivariable analysis showed that there was no signifi-
cant difference in survival in patients treated with surgery
alone, surgery with adjuvant radiation, or surgery with
adjuvant chemoradiation. The small number of patients
treated with surgery alone made statistical comparisons
between this group of patients and those receiving adju-
vant radiation or chemoradiation treatment underpowered.
However, the robust number of patients receiving adju-
vant radiation treatment (
n
5
89) and adjuvant chemora-
diation treatment (
n
5
143) allowed us to draw
meaningful statistical comparisons between these groups.
After controlling for all other variables, no difference in
survival was seen between patients treated with surgery
with adjuvant radiation versus surgery with adjuvant che-
moradiation (
p
5
.6306). In the HPV-positive subgroup,
no difference was seen in patients treated with surgery
with adjuvant radiation versus surgery with adjuvant che-
moradiation (
p
5
.4707). Similarly, in the HPV-negative
subgroup, no difference was seen in patients treated with
surgery with adjuvant radiation versus surgery with adju-
vant chemoradiation (
p
5
.8493).
Gastrostomy tube outcomes
In an effort to determine functional outcomes in this
cohort, the presence of a gastrostomy tube was docu-
mented. Patients were included based on the presence of
a gastrostomy tube, rather than gastrostomy tube depend-
ence, and this group included patients who were using the
gastrostomy tube for at least a portion of their diet. Gas-
trostomy tubes were present in 12.8%, 23.3%, and 32.1%
of patients at 1, 3, and 5 years, respectively. Gastrostomy
tube dependence rates were impacted by surgical
approach, with the open approach cohort accounting for
the majority of patients who were gastrostomy tube
dependent. Gastrostomy tube presence was lowest in
patients with T1/T2 tumors undergoing transoral resec-
tion, whereas the rate of tube dependence was 7.84% for
T1/T2 classification and 9.52% in patients with T3/T4
classification (Table 4).
DISCUSSION
This study provides strong evidence that HPV status is
the most important predictor of overall survival in a large,
surgically treated oropharyngeal SCC cohort. For the
entire cohort, 3 and 5 year survival rates were 71.3% and
65.1%, respectively. However, for HPV-positive patients,
survival rates at 3 and 5 years were 83.3% and 81.8%,
respectively, compared to 53.3% and 40.3% for HPV-
negative patients. These outcomes are comparable to che-
moradiotherapy trials for the same disease site.
13
When
adjusting for other covariates (surgical approach, mucosal
margins, perineural invasion, and smoking status), HPV
status, ECS, and tumor classification were significantly
associated with overall survival. Unlike previously
reported primary chemoradiation studies, smoking status,
stratified risk levels, and neck disease did not impact sur-
vival in surgically treated patients.
15
TABLE 3. Multivariable analysis of outcome predictors.
Analysis
Overall,
n
5
260
HPV negative,
n
5
108
HPV positive,
n
5
152
Variables
HR
95% CI
p
value
HR
95% CI
p
value
HR
95% CI
p
value
Approach
Transoral
Ref
Ref
Ref
Open
1.343 0.788–2.288 .2784
0.79
0.4–1.561
.4984
3.09 1.293–7.385 .0111
Extranodal extension
No
Ref
Ref
Ref
Yes
1.938 1.262–2.976 .0025 2.322 1.359–3.968 .0021 1.119 0.536–2.335 .7644
HPV
Positive
Ref
Negative
2.362 1.496–3.731 .0002
N/A
N/A
N/A
N/A
N/A
N/A
Mucosal margins
Free of carcinoma
Ref
Ref
Ref
Positive
1.621 0.969–2.711 .0656 1.213 0.614–2.395 .5787 2.519 1.101–5.766 .0287
Perineural invasion
No
Ref
Ref
Ref
Yes
1.398 0.901–2.17
.1347 1.407 0.82–2.414
.2153
1.14 0.514–2.529 .7466
Smoking status
10 pack-years
Ref
Ref
Ref
>
10 pack-years
1.316 0.763–2.27
.3235 1.452 0.637–3.311 .3747 1.302 0.616–2.751 .4894
T classification
T1/T2
Ref
Ref
Ref
T3/T4
1.937 1.187–3.16
.0081 2.029 1.054–3.
906 .0342 2.125 0.983–4.595 .0555
Abbreviations: HPV, human papillomavirus; HR, hazard ratio; 95% CI, 95% confidence interval.
S
URGICAL MANAGEMENT OF OROPHARYNGEAL
SCC
HEAD & NECK—DOI 10.1002/HED APRIL 2016
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