Following the publication of the National Polyp Study [1] showing the efficacy of polypectomy in preventing colorectal cancer (CRC) incidence
and 2 subsequent prospective series showing the feasibility of colonoscopy as primary
screening technique [2]
[3], over 60 % of the American population and 10 % to 20 % of the European population
have undergone colonoscopy for screening purposes [4]
[5].
The strict association between the diagnostic performance of the individual endoscopist,
assessed by adenoma detection rate (ADR), and the risk of post-colonoscopy interval
cancer led to the general conviction that the degree of protection following colonoscopy
screening could be affected by its technical performance [6]
[7]. This was confirmed by the high variability in ADR among different endoscopists
in similar or equivalent settings, as well as by the identification of relevant predictors
of that variability, such as withdrawal time, level of cleansing, and expertise of
the endoscopist [8]
[9].
This evidence led to the analogy between airline companies and endoscopy services.
As the former succeeded in minimizing the risk of accidents by implementing solid
policies involving extensive pilot training and retraining, similar policies have
been proposed for individual endoscopists performing screening colonoscopies. For
instance, short retraining courses mainly focusing on lesion recognition and withdrawal
technique resulted in long-term improvement in technical performance as measured by
ADR, which in turn is likely to reduce risk of post-colonoscopy interval CRC [10]. Similarly, implementation of split-dose regimen resulted in a substantial increase
in ADR [11]. In addition, assessment of competence of senior endoscopists based on direct observation
by expert endoscopists has become a prerequisite to practice within the United Kingdom
(UK) population-based screening system [12].
When considering technical competence as the main driver of CRC prevention, training
is critical. To grade trainee competence, a paradigm shift from the simplistic minimum
number of procedures to a more structured system, based on objective and articulated
assessment of competence, has been proposed. In detail, the assessment of competency
in endoscopy (ACE) system implemented in the United States is based on a complex assessment
of cognitive and motor skills during 5 consecutive endoscopies after each 50 colonoscopies
of the trainee. Improvement in the ACE score has been associated with a higher proficiency
in the main quality indicators, such as cecal intubation rate and polyp detection
rate [13]
[14]. Similarly, an assessment tool based on direct observation (DOPS) of the trainees
can reassure the medical and non-medical community that only trainees with adequate
skills will perform endoscopy without supervision in routine practice, reducing the
variability in technical performance.
However, there are still 2 main pitfalls in training policies. First, formal training
programs, based on objective assessment of competence, are lacking in several countries,
especially in Europe. This may be at least partially explained by the lack of robust
literature validating such programs. For instance, none of these training modules
was validated in a randomized setting. Second, these programs mainly deal with the
diagnostic phase of colonoscopy, with less or no focus on endoscopic resection. On
one hand, this is expected, when considering the relevance of the learning curve in
cecal intubation rate for trainees, due to both the complexity of the insertion phase
and the clinical importance of a complete examination. In addition, competence in
diagnosis may be assessed on consecutive colonoscopies, simplifying the integration
between training and daily routine. On the other hand, endoscopic resection (i. e.,
polypectomy and endoscopic mucosal resection [EMR]) represents a crucial step in efficacy
and safety of colonoscopy, as incomplete resection has been strictly associated with
the risk of interval CRC [15], and most major adverse events associated with colonoscopy (i. e., bleeding and
perforation) are actually related to endoscopic resection rather than to the diagnostic
phase of colonoscopy
In this issue of Endoscopy International Open, Patel K et al. report on an international
survey of how training and competence assessment in polypectomy are performed [16]. Overall, 610 endoscopists (57 % trainers, 43 % trainees) from 20 countries addressed
general training in polypectomy, as well as specific programs for more advanced interventions,
such as resection of large polyps or mucosectomy [16].
The picture that emerged from the survey is quite dismal. First, trainers in most
countries reported lack of specific national guidelines on this issue. This underscores
that competence in polypectomy has not been incorporated in the professional standard
for the endoscopist, leaving exploitation of formal international training programs
to the willingness of individual trainers rather than to a nationwide approach.
Second, most trainees reported lack of training for polypectomy of large polyps as
well as in endoscopic mucosal resection (EMR). This is quite disturbing for several
reasons. First, the rate of incomplete polypectomy appeared to be strictly associated
with lesion size. In particular, the rate has been reported to be nearly 20 % for
experienced endoscopists [17]. Thus, higher rates due to inadequate training may have worrisome consequences for
cancer prevention, especially because these lesions usually represent the most advanced
step of the adenoma-carcinoma sequence. Second, lack of training in EMR may result
in an inability to remove large flat lesions, such as granular- or mixed-type lateral
spreading tumors (LST). That may help explain why too many patients with benign LST
amenable of endoscopic resection are still referred for unnecessary surgery.
Third, only half of the trainees reported systematic use of some type of formal assessment
for polypectomy competence, making it likely that rates for such an assessment are
very low outside UK and the United States. That is a significant issue, when considering
that, unlike with diagnostic colonoscopy, polypectomy requires individual assessment
of several sequential phases, such as assessment of the lesion, positioning of the
scope, choice of prophylactic actions (i. e., submucosal injection, loop, etc.), selection
of the device, type of current, and assessment of post-polypectomy scar. This is very
well summarized in the Directly Observed Polypectomy Skills (DOPyS) tool, recently
validated in the UK [18].
The main limitations of the survey by Patel K et al. are represented by the selection
bias of the operators who replied to the survey, and by a possible heterogeneity in
participation among individual countries, so that the survey may not fully represent
the balance in training policies among the countries surveyed [16]. However, these limitations are likely to skew the data toward a more favorable
picture, in that endoscopists who and countries that have an already established specific
interest in polypectomy training were more prone to responding to the questions. In
addition, such selection bias seemed to more frequently affect the trainers rather
than the trainees, with the former describing a more gloomy scenario, which underlines
the importance of specifically including the trainees in such surveys, as was done
by the authors.
Overall, the data by Patel K et al. show an inadequate and fragmented policy of polypectomy
training in most of the countries, which is likely to result in suboptimal performance
by post-training endoscopists. That is more alarming when considering that adoption
of mass population screening programs is resulting in an enormous increase in the
number of colonoscopies performed, prompting employment of new endoscopists to manage
to the rising number of colonoscopies. The only positive news, if any, is that the
lack of adequate training programs leaves significant room for improvement, which
should spur international societies to quickly implement policies aimed at selection,
adoption, and further validation of training programs. In that regard, the favorable
experiences that have already been documented in the United States and UK may be a
reasonable starting point.
