170 / 220
age, sex, smoking status and baseline diet. There was a non-
significant difference in the number of patients who received
induction chemotherapy between the two groups, although the
total number of cycles of concurrent chemotherapy delivered
was similar. The difference in mean contralateral parotid dose
between the two groups was not significant.
Patient-reported swallowing function measured using the
MDADI was superior for patients managed with an NG tube as
required compared with a prophylactic gastrostomy: overall com-
posite score 68.1 versus 59.4 (
p
= 0.04), global score 67.7 versus 60
(
p
= 0.04), emotional subscale 73.5 versus 60.4 (
p
< 0.01), func-
tional subscale 75.4 versus 61.7 (
p
< 0.01), and physical subscale
59.6 versus 57.1 (
p
= 0.38). The composite total, global and
domain-specific (physical, emotional and functional) subscales
for each group are detailed in
Table 2
. Each domain is scored 0–
100 with higher scores indicating better swallow function. A uni-
variate analysis was performed to explore the relationship
between patient, tumour and treatment factors with MDADI scores
(
Table 3
). Age, T stage, N stage, and treatment factors including use
of induction chemotherapy, number of concurrent chemotherapy
cycles and mean contralateral parotid dose, did not correlate with
MDADI scores in any domain. By contrast, the quality of pre-
treatment diet according to a simple scale of consistency was
found to be significantly associated with all domains of the MDADI
other than the global subscale. This was confirmed on a multivari-
ate analysis, with only having a more normal pre-treatment oral
intake was significantly associated with higher MDADI emotional
(
p
= 0.02), physical (
p
= 0.01), total (
p
= 0.02) and possibly func-
tional (
p
= 0.06) scores.
Discussion
Long term swallow function is a major survivorship issue
[4]
.
There have been conflicting reports regarding whether the use of
a prophylactic gastrostomy may have a detrimental impact upon
long term swallow function compared with a reactive approach.
Chen et al.
[22]
reported an increased risk of late oesophageal
strictures requiring dilatation (30% versus 6% for the prophylactic
versus reactive approach). A recent retrospective study reported
a 5-year incidence of severe late dysphagia in 30.8% of the reactive
NG tube cohort (
n
= 36), and 60.9% in the prophylactic PEG cohort
(
n
= 25) with a PEG being associated with an increased rate of sev-
ere late dysphagia on a multivariate analysis
[21]
; however, the
prophylactic PEG cohort were a historically earlier cohort prior to
a shift in the institutional approach to enteral feeding. Mekhail
et al. reported a 30% versus 8% dysphagia rate at the relatively early
time point of 6 months post treatment for gastrostomy versus NG
feeding
[30]
. In a prospective study Corry
[31]
similarly found an
increase in grade 3 dysphagia with the use of a gastrostomy (25%
versus 8%) at the same 6 month timepoint post-treatment. Oozeer
et al.
[32]
used patient-reported swallow outcomes obtained using
the validated MD Anderson Dysphagia Inventory (MDADI) ques-
tionnaire to perform a matched pair analysis in a group of 31
patients who completed the questionnaire at least 2 years post-
treatment; the MDADI scores for all domains were significantly
superior for the reactive NG group compared with the prophylactic
gastrostomy group. By contrast, one prospective randomised study
[18]
reported that the prophylactic PEG group had a lower rate of
long term grade 3 dysphagia (3% versus 9%) and a higher propor-
tion of patients who resumed a normal diet (93% versus 80%)
[18]
. Recent systematic reviews have reported that the impact of
prophylactic PEG use on swallowing and swallow-related out-
comes remains unclear and an area of clinical equipoise
[33,34]
.
This remains an area of controversy and wide variation in practice
[10]
. An ongoing randomised trial
[35]
may prove to be informative
if recruitment can be successfully completed, although previous
randomised studies have failed to complete recruitment
[36]
.
We have previously reported long term patient-reported swal-
low outcomes in a cohort of patients treated in the era of 3D-
conformal radiotherapy
[1]
. However, advances in radiotherapy
techniques may impact upon swallow function, and conclusions
from studies performed in the 3D-conformal radiotherapy era are
not necessarily applicable to the IMRT era. Advances such as the
introduction of parotid sparing IMRT have reduced xerostomia
[37]
and may benefit swallow function; by contrast, the move from
3D-conformal radiotherapy with a matched anterior neck field
with midline shielding to whole field IMRT has led to an increase
in the midline neck dose, including the larynx and pharyngo-
oesophageal axis. The impact of this remains unclear, with an
uncertain dose response for swallow dysfunction. An alternative
technique is matching IMRT with a neck field, and it remains
unclear whether this has a favourable impact upon swallow func-
tion compared with whole field IMRT
[2]
. There is currently inter-
est in developing ‘swallow-sparing’ IMRT, although at present the
efficacy of this approach remains uncertain
[2]
.
Assessment of swallow outcomes is complex, with multiple
potential tools, including physician assessed toxicity scores,
patient reported function, and physical outcomes including stric-
ture rates
[2]
. Patient and clinician reported outcomes may both
be valuable, although it is recognised that clinicians may underes-
timate dysphagia compared with patients
[38]
. The MDADI is a val-
idated tool for assessing patient reported swallowing outcomes
[25]
. In addition to the method of swallow assessment, the timing
is likely to be a critical factor influencing outcome. For example
MDADI scores have been found to significantly improve at
12 months post treatment when compared with earlier timepoints
[4]
. These data suggest that swallow function is continuing to
improve 12 months post-treatment and may have yet to plateau.
This is consistent with the observation that salivary recovery does
not plateau until two years post treatment
[37]
.
This study has addressed the important clinical question of
whether the use of a prophylactic gastrostomy or a reactive NG
Table 2
MDADI scores according to intended enteral feeding route.
Prophylactic
gastrostomy (
N
= 26)
NG as needed
(
N
= 26)
p
-value
Total: Mean (SD)
59.4 (16.8)
68.1 (12.9)
0.04
Global: Mean (SD)
60 (26.5)
67.7 (24.7)
0.04
Physical: Mean (SD)
57.1 (14.9)
59.6 (11.4)
0.38
Emotional: Mean (SD)
60.4 (19.1)
73.5 (15.1)
<0.01
Functional: Mean (SD)
61.7 (20.1)
75.4 (15.5)
<0.01
Values which are statistically significant are shown in bold.
Table 3
Univariate analysis of predictors of MDADI score.
Factor
p
-value
Total Global Physical Emotional Functional
Age
0.34 0.78 0.5
0.53
0.22
T stage
0.71 0.83 0.74
0.52
0.68
N stage
0.11 0.42 0.06
0.09
0.16
Induction chemo
0.37 0.39 0.52
0.44
0.26
No. induction chemo
cycles
0.11 0.45 0.33
0.16
0.05
Conc chemo type
0.1 0.15 0.08
0.06
0.11
No. conc chemo cycles 0.19 0.84 0.27
0.18
0.30
Pre-treatment diet
0.02
0.16
<0.01 0.02
0.03
Mean contralateral
parotid dose
0.16 0.46 0.60
0.07
0.06
Values which are statistically significant are shown in bold.
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