Graser, Anno

Kolligs, Frank T.

English

A. Graser

F. T. Kolligs

Crossref

Authors' response to Hassan et al

Open Access LMU ( Ludwig-Maximilians-Univ. München)

Authors’ response to Hassan et alRegarding the letter to the editor by Hassanet al (in the January issue of Gut),1 we agreethat not all patients in whom diminutivepolyps are identified should be referred tocolonoscopy for resection of these lesions.However, we noted in our trial2 that highresolution CT colonography (CTC) allowsfor reliable identification of lesions that are<10 mm; even polyps that are <6 mm insize will be detected at a sensitivity of 72% ifthey are adenomas, and 59% if they are non-adenomas. We agree that based on 13 lesionsthat were detected in our study populationno general recommendation can be made.Nevertheless, we want to emphasise thatmost radiologists will find it difficult to notreport a finding that can be clearly identified.When looking at our data more carefully,one has to note that in only two patients(0.6%) was the largest lesion <6 mm andshowed advanced histology, and in threepatients (1.0%) whose largest lesion was<10 mm this polyp was an advancedadenoma. These data are similar to thosereported by Lieberman et al,3 where advancedhistology was found in 1.7% of patientswhose largest lesion was <6 mm, and in6.6% of patients with <10 mm polyps only.In this study, the authors concluded thatpatients with lesions <10 mm should beoffered colonoscopy. Similarly, Butterly andcolleagues4 reported that out of 1933 small(5e10 mm) and diminutive (#4 mm) polypsfound in 1235 asymptomatic patients, 10.1%and 1.7% of lesions, respectively, wereadvanced adenomas. These figures againagree well with our findings.As long as CTC is not integrated intocolorectal cancer screening programmes, it willnot be used on sufficient numbers of screeningparticipants to clarify finally whether or notthe referral of patients with small lesionswill be cost-effective or beneficial for theindividual patient. In our study populationthe fact that more advanced adenomas (AAs)were detected in lesions <6 mm than in6e9 mm polyps can be attributed to samplesize bias. Generally, we agree that more AAsshould be found in larger lesions.Regarding size measurements of polyps,we feel that our classification of lesions wasprobably more accurate than what Hassanand colleagues suggest. Most researchersagree that CTC is more exact in determiningpolyp sizes than colonoscopy (OC), and thatcomparison of a lesion with a biopsy forcepsis not an accurate way of determining itstrue dimensions. Accordingly, we used CTCsize measurements to classify polyps, andOC was used for comparison only; if a lesionwas significantly smaller or larger on OCthan on CTC, CTC measurements wereused as the gold standard.Anno Graser, Frank T KolligsUniversity of Munich, GermanyCorrespondence to Dr Anno Graser, Marchioninistr.15, Munich, D-80992, Germany;anno.graser@med.uni-muenchen.deCompeting interests None.Provenance and peer review Not commissioned; notexternally peer reviewed.Gut 2010;59:860. doi:10.1136/gut.2009.196543REFERENCES1. Hassam C, Pickhardt PJ, Laghi A, et al. Should werefer diminutive polyps to post-CTC polypectomy?Gut 2010;59:137.2. Graser A, Stieber P, Nagel D, et al. Comparison of CTcolonography, colonoscopy, sigmoidoscopy and faecaloccult blood tests for the detection of advancedadenoma in an average risk population. Gut2009;58:241e8.3. Lieberman D, Moravec M, Holub J, et al. Polypsize and advanced histology in patients undergoingcolonoscopy screening: implications for CTcolonography. Gastroenterology 2008;135:1100e5.4. Butterly LF, Chase MP, Pohl H, et al. Prevalence ofclinically important histology in small adenomas. ClinGastroenterol Hepatol 2006;4:343e8.860 Gut June 2010 Vol 59 No 6PostScriptdoi: 10.1136/gut.2009.196543 2010 59: 860Gut Anno Graser and Frank T Kolligs et alAuthors' response to Hassan  http://gut.bmj.com/content/59/6/860.full.htmlUpdated information and services can be found at: These include:References http://gut.bmj.com/content/59/6/860.full.html#ref-list-1This article cites 4 articles, 2 of which can be accessed free at:serviceEmail alertingthe box at the top right corner of the online article.Receive free email alerts when new articles cite this article. Sign up inNotes http://group.bmj.com/group/rights-licensing/permissionsTo request permissions go to: http://journals.bmj.com/cgi/reprintformTo order reprints go to: http://group.bmj.com/subscribe/To subscribe to BMJ go to: group.bmj.com on January 17, 2014 - Published by gut.bmj.comDownloaded from 

Patients with m2 antibodies: what diagnosis and follow-up are they given? Response to Hassan et al.

Universität München: Elektronischen Publikationen

Authors’ response to Hassan et al
Regarding the letter to the editor by Hassan
et al (in the January issue of Gut),1 we agree
that not all patients in whom diminutive
polyps are identified should be referred to
colonoscopy for resection of these lesions.
However, we noted in our trial2 that high
resolution CT colonography (CTC) allows
for reliable identification of lesions that are
<10 mm; even polyps that are <6 mm in
size will be detected at a sensitivity of 72% if
they are adenomas, and 59% if they are non-
adenomas. We agree that based on 13 lesions
that were detected in our study population
no general recommendation can be made.
Nevertheless, we want to emphasise that
most radiologists will find it difficult to not
report a finding that can be clearly identified.
When looking at our data more carefully,
one has to note that in only two patients
(0.6%) was the largest lesion <6 mm and
showed advanced histology, and in three
patients (1.0%) whose largest lesion was
<10 mm this polyp was an advanced
adenoma. These data are similar to those
reported by Lieberman et al,3 where advanced
histology was found in 1.7% of patients
whose largest lesion was <6 mm, and in
6.6% of patients with <10 mm polyps only.
In this study, the authors concluded that
patients with lesions <10 mm should be
offered colonoscopy. Similarly, Butterly and
colleagues4 reported that out of 1933 small
(5e10 mm) and diminutive (#4 mm) polyps
found in 1235 asymptomatic patients, 10.1%
and 1.7% of lesions, respectively, were
advanced adenomas. These figures again
agree well with our findings.
As long as CTC is not integrated into
colorectal cancer screening programmes, it will
not be used on sufficient numbers of screening
participants to clarify finally whether or not
the referral of patients with small lesions
will be cost-effective or beneficial for the
individual patient. In our study population
the fact that more advanced adenomas (AAs)
were detected in lesions <6 mm than in
6e9 mm polyps can be attributed to sample
size bias. Generally, we agree that more AAs
should be found in larger lesions.
Regarding size measurements of polyps,
we feel that our classification of lesions was
probably more accurate than what Hassan
and colleagues suggest. Most researchers
agree that CTC is more exact in determining
polyp sizes than colonoscopy (OC), and that
comparison of a lesion with a biopsy forceps
is not an accurate way of determining its
true dimensions. Accordingly, we used CTC
size measurements to classify polyps, and
OC was used for comparison only; if a lesion
was significantly smaller or larger on OC
than on CTC, CTC measurements were
used as the gold standard.
Anno Graser, Frank T Kolligs
University of Munich, Germany
Correspondence to Dr Anno Graser, Marchioninistr.
15, Munich, D-80992, Germany;
anno.graser@med.uni-muenchen.de
Competing interests None.
Provenance and peer review Not commissioned; not
externally peer reviewed.
Gut 2010;59:860. doi:10.1136/gut.2009.196543
REFERENCES
1. Hassam C, Pickhardt PJ, Laghi A, et al. Should we
refer diminutive polyps to post-CTC polypectomy?
Gut 2010;59:137.
2. Graser A, Stieber P, Nagel D, et al. Comparison of CT
colonography, colonoscopy, sigmoidoscopy and faecal
occult blood tests for the detection of advanced
adenoma in an average risk population. Gut
2009;58:241e8.
3. Lieberman D, Moravec M, Holub J, et al. Polyp
size and advanced histology in patients undergoing
colonoscopy screening: implications for CT
colonography. Gastroenterology 2008;135:1100e5.
4. Butterly LF, Chase MP, Pohl H, et al. Prevalence of
clinically important histology in small adenomas. Clin
Gastroenterol Hepatol 2006;4:343e8.
860 Gut June 2010 Vol 59 No 6
PostScript
doi: 10.1136/gut.2009.196543
 2010 59: 860Gut
 
Anno Graser and Frank T Kolligs
 
et alAuthors' response to Hassan 
 http://gut.bmj.com/content/59/6/860.full.html
Updated information and services can be found at: 
These include:
References
 http://gut.bmj.com/content/59/6/860.full.html#ref-list-1
This article cites 4 articles, 2 of which can be accessed free at:
service
Email alerting
the box at the top right corner of the online article.
Receive free email alerts when new articles cite this article. Sign up in
Notes
 http://group.bmj.com/group/rights-licensing/permissions
To request permissions go to:
 http://journals.bmj.com/cgi/reprintform
To order reprints go to:
 http://group.bmj.com/subscribe/
To subscribe to BMJ go to:
 group.bmj.com on January 17, 2014 - Published by gut.bmj.comDownloaded from 


http://epub.ub.uni-muenchen.de/18007/1/oa_18007.pdf

Patients with m2 antibodies: what diagnosis and follow-up are they given? Response to Hassan et al.

Abstract

Similar works

Full text

Available Versions

Crossref

Open Access LMU ( Ludwig-Maximilians-Univ. München)

Universität München: Elektronischen Publikationen