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relative risk (RR range 0.35 to 4.4) varied greatly
between studies4,6,7,15,18 (Table II). This indicates that
studies showed different results on which surgical proce-
dure would result in the lowest disease recidivism per-
centage. Nyrop and Bonding7 reported the largest
absolute risk reduction: 61% (46% to 76%) in favor of the
CWD procedure.
We identified three articles that made a distinction
between residual and recurrent disease4,15,18 (Table III).
Roden et al.18 found a significant higher risk of residual
disease in the CWU group (20.4% vs. 4.7%, P 5.03).
Recurrence risks between both techniques were equal
(Table III). Similarly, Declerck found more residual dis-
ease after the CWU procedure (17.6% vs. 0%).4 However,
also more recurrent disease was found after the CWU
procedure (8.1% vs. 0%) (Table III).4 Stankovic showed
opposite results: less residual (3.1% vs. 7.0%) and recur-
rent disease (4.7% vs. 15.1%) occurred in the CWU group
(Table III).15 We used data from the latter three studies
to calculate the risk difference and relative risk for cho-
lesteatoma residual and recurrent disease (Table III).
Two studies showed a risk difference in favor of CWD for
residual disease: 16% and 18%, respectively.4,18 In addi-
tion, recurrent disease risk difference showed to be in
favor of CWD in the studies of Declerck4 (8%) and Roden
et al.18 (4.4%) (Table III). Contrarily, Stankovic15 found a
risk difference in favor of CWU for both residual (risk
reduction 24%; relative risk 0.43) and recurrent disease
(risk reduction 210%; relative risk 0.31) (Table III).
DISCUSSION
We reviewed the literature to assess which surgical
removal technique for adult acquired cholesteatoma
(CWU or CWD) provided the lowest rate of disease recid-
ivism. The number of available studies was substantial.
The seven included studies were all of moderate or high
relavance. However, the validity of included studies
ranged from low to moderate.
The majority of included studies showed that adult
cholesteatoma patients suffer from a higher recidivism risk
after the CWU procedure as compared to the CWD proce-
dure. Three studies4,15,18 reported on residual and recurrent
disease rates independently. Canal wall up recidivism was
more likely to be residual disease, whereas CWD recidivism
tended to be recurrent disease. Because CWU is not per-
formed in severe cases in common practice, and the feasibil-
ity of performing CWU or CWD is related to the severity of
the disease, confounding by indication might have masked
even higher disease recidivism percentages.23 This con-
founding could explain heterogeneity in our results: Stan-
kovic15 showed significant results in favor of CWU. In this
study, severity of the disease was different between study
populations; extensive disease, a small mastoid and a dam-
aged posterior wall were indications for CWD surgery. Only
Nyrop and Bonding’s study7 was unaffected by confounding
by indication. Authors described CWU and CWD groups to
be similar regarding the extent of cholesteatoma disease.
The latter results showed higher CWU recidivism rates
compared to results from the CWD technique (P < .0001).
Because Nyrop and Bonding’s study7 provided the most
unbiased insight according to our CAT, we recommend that
the CWD procedure should be performed in adult patients
with acquired cholesteatoma.
Tomlin et al.5 performed a meta-analysis on the
risk of cholesteatoma recidivism after CWU and CWD.
Authors reported a lower percentage of residual and
recurrent disease after CWD (range 5% to 17%) com-
pared to CWU surgery (range 9% to 70%). The relative
risk of recurrent or residual disease was 2.87 (95% confi-
dence interval: 2.45 to 3.37) after CWU compared to
CWD. The results of Tomlin et al.5 are in line with our
findings, although the inclusion of Stankovic’s article15
in the current review introduces new uncertainty about
the generalizability of reported surgical outcomes. Tom-
lin et al.5 included 13 articles, of which three were
included in our study.6,7,18 In contrast to Tomlin et al.,5
results from our selected studies could not be pooled in
meta-analysis, a difference that marks a more heteroge-
neous and different retrieval of literature. Similar to
their included studies,5 none of our included studies
mentioned the use of magnetic resonance imaging (MRI)
in detecting cholesteatoma recidivism in CWU patients.
This could be explained by recent MRI use in CWU
follow-up, whereas the majority of included studies was
performed before 2006 and consisted of retrospective
case series of earlier performed surgeries. Compared to
Tomlin’s study, we provide additional insight because we
excluded children, and in addition calculated relative
risks and absolute risk reductions (both significant in
five out of seven selected studies4,6,7,15,18).
Risk of Bias
In interpreting the findings, the following consider-
ations need to be taken into account. Firstly, included
studies differed in their methods of follow-up. Studies
with a shorter duration of follow-up might have been
subjected to bias in favor of CWU.4,7,15,18
Secondly, in the detection of residual or recurrent
cholesteatoma, second-look surgery is a more sensitive
method compared to clinical examination in CWU
patients. 24 Therefore, results of the study that applied
second-look surgery 4 might be influenced by the higher
sensitivity of confirmation of disease recidivism. How-
ever, diffusion-weighted MRI is expected to replace
second-look surgery completely to detect cholesteatoma
recidivism in the near future.5 Diffusion-weighted imag-
ing has shown to have high sensitivity and specificity for
detecting cholesteatoma, especially nonecho planar
diffusion-weighted MRI. 25 Lastly, surgical experience
needs to be taken into consideration, because differences
in skills can lead to different outcomes. However, none
of our included studies mentioned the experience of the
surgeons. Therefore, we cannot exclude the possibility of
one surgeon achieving superior results when applying
either one of the techniques.
Surgical Considerations
Several factors need to be taken into account when
opting for a CWU or CWD operation: hearing outcome,
Laryngoscope 126: April 2016 Kerckhoffs et al.: A Review on Cholesteatoma Recidivism After CWU and CWD
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