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familial adenomatous polyposis ( fap ) accounts for less than 1  % of all colorectal cancers 1 .
the traditional treatment is total proctocolectomy , though subtotal colectomy is used in some cases that are accompanied by low rectal polyp burdens .
patients with low polyp burdens may choose to delay colectomy to avoid complications of surgery , including the potential for development of desmoid tumor , loss of fecundity in women , and diarrhea after total proctocolectomy .
for patients who have undergone total proctocolectomy , endoscopic control of a high polyp burden is important to avoid any consideration of surgical resection of the ileo - anal pouch . in this report
, we described the use of large - scale cold snare polypectomy to delay surgery in fap patients .
procedures were performed with olympus ( olympus corporation , center valley , pa , united states ) colonoscopes or upper endoscopes and cold snaring was performed with an 11-mm captiflex ( boston scientific , marlborough , ma , united states ) snare .
we retrospectively examined a database of patients with polyposis syndromes managed by one of the authors ( dkr ) and maintained at indiana university hospital and identified patients with fap .
patients with fap were excluded if they had undergone total proctocolectomy and did not have significant polyp burden in the ileo - anal pouch , or if they had an intact colon or rectum and had never had more than 30 polyps removed in one procedure in an attempt to endoscopically control polyp burden , if they had an intact colon or rectum and had a polyp burden that was too great for attempted endoscopic control , or if they had one procedure and no follow - up at our center .
permission to review the de - identified database was granted by the institutional review board at indiana university health on june 15 , 2015 .
all procedures were performed with standard olympus high resolution or high definition colonoscopes without chromoendoscopy .
the initial and subsequent procedures and polypectomies were considered successful if the number of polyps detected at follow - up examinations was similar to or lower than previous examinations and if no or only a few large polyps (   1  cm in size ) were detected at follow - up examinations . in the initial endoscopic procedure performed to control polyp burden , polyps   1  cm in size were removed by hot snaring , including endoscopic mucosal resection in some cases .
a nurse counted the number of polyps cold snare resected as they were removed . in patients with intact colons
, polyps were typically resected from the cecum and ascending colon with no attempt at retrieval until resections were completed in those sections of the colon .
once the cecum and the ascending colon were cleared , the snare was withdrawn and the detected polyps were suctioned into a trap for pathologic examination .
that process was then repeated for the transverse colon , the left colon including the descending and sigmoid colon , and finally the rectum .
complications were identified by chart review , direct interview at follow - up examination , and follow - up telephone call 24   
there were 21 ( 11 female ) patients with an intact colon or rectum or ileo - anal pouch , in which an initial examination included at least 30 polyps removed by cold snare polypectomy , and in which the patient had at least one follow - up at our institution .
all of the patients apart from one had known adenomatous polyposis coli ( apc ) mutations or were family members of patients with known apc mutations .
the mean age of the 21 patients was 37 years , and 7 of the 10 patients with intact colons were under age 30 . 
of these 21 patients , 10 had intact colons at the first examination , 6 had intact rectums , and 5 were status post total colectomy with significant polyp burdens in the ileo - anal pouch .
only one of the pouch patients was being considered for surgery by the referring physician , and this patient had a very heavy pouch polyp burden ( see below ) . across the 21 patients ,
more than 99  % of all polyp resections were performed by cold snare polypectomy .
there were seven patients who received nonsteroidal anti - inflammatory drugs ( nsaids ) throughout the study interval , one received aspirin , and the remainder were not on nsaids .
all but two had been placed on nsaids before referral to our center and did not have an apparent response .
the number of procedures performed to control the polyp burden ranged from 2 to 5 , with mean 3.1 .
one of these had an intact colon and had 57 polyps removed at the baseline colonoscopy and 105  at a second procedure 13 months later , though no polyps >  1  cm in size were identified at the follow - up . 
a second patient with an intact colon had 200 polyps removed in a first colonoscopy , 20 in a second colonoscopy performed 10 months later , and 50  at a third colonoscopy 11 months after the second . in a fourth colonoscopy ,
60 were removed from the rectum only , and the patient was then referred for subtotal colectomy . for all patients ,
the mean number of polyps removed in the first examination was 85 , median 65 , range 30    342 .
for all 21 patients , the number of polyps removed at the second procedure was mean 40 , median 31 , range 2    105 .
other than the two patients referred to surgery , polyp counts in all patients went down at subsequent examinations .
for example , the largest number of polyps resected in one procedure was 342 in a patient with an ileo - anal pouch who had neglected follow - up for 7 years . at the second procedure performed 3 months later , 28 polyps were removed by cold snare .
this was the only patient who still had polyps   10  mm at the second procedure .
no patient had a complication from polypectomy . all polyps resected were tubular or tubulovillous adenomas and no adenoma
table  1 shows the number of polyps removed at the initial procedure and the procedure times for the initial procedure grouped by patient anatomy .
for example , the longest initial procedure was 96 minutes in the pouch patient who had 342 polyps removed during that procedure , or an average of 3.6 polyps per minute for the entire procedure .
in this report , we describe reduction of polyp burdens in retained colon , rectum or ileo - anal pouch in a subset of patients with fap in whom at least 30 lesions were removed and polypectomies were performed largely with cold snaring . in an initial endoscopic procedure , there was an attempt to achieve endoscopic control of polyp burdens , and at least one follow - up examination was performed at our institution .
no patient developed cancer and only one had any large adenomas during follow - up .
to our knowledge , no previous report has described the use of large scale cold snaring to control the polyp burden in fap .
reliance on large scale cold snaring rather than ablative tools such as argon plasma coagulation ( apc ) is the unique and novel aspect of this report .
cold snaring has the potential to be more effective than apc , since snaring is more effective than ablation 2 , and less likely to produce complications since cold techniques produce fewer complications than other methods 3
. limitations of this study include its retrospective nature and limited follow - up in some patients .
however , all patients had at least one follow - up and all but two patients had fewer and smaller polyps at follow - up .  in some of our patients , continued chemoprevention
the relative importance of cold snaring and chemoprevention in some patients was uncertain and endoscopic therapy and chemoprevention are often considered complimentary approaches to polyp control in fap 6 
 7 
 8 
 9 .
we used the approach of large scale cold snaring in about a quarter of our fap patients .
thus , most patients with fap in our database had either already undergone total proctocolectomy and were referred for management of duodenal lesions , or had subtotal colectomies and had a relatively low total burden of rectal polyps ( some needed endoscopic mucosal resection of a large rectal polyp but did not have rectal carpeting ) .
the patients described in this series had polyps burdens that were larger but were subjectively endoscopically manageable 10 
 11 , typically wanted to delay surgery ( e.  g. until after childbearing , because of a family history of desmoids , or to maintain quality of life by retaining a rectum or ileo - anal pouch in a patient who had already been operated ) , and indicated they were ready to adhere to recommended follow - up . assessing what is an endoscopically manageable polyp burden is partly subjective 10 
 11 , but includes consideration of the number and size of polyps and whether colectomy has already been performed .
the patient with 342 polyps resected in the first examination was considered a candidate for endoscopic management because of the importance of preserving his ileo - anal pouch .
clearly , the polyp size range appropriate for endoscopic management is considerably larger in a patient who has already had a total or abdominal colectomy compared to the patient with an intact colon 1 . although we describe here the use of cold snaring in patients with substantial polyp burdens ( at least 30 polyps ) , to demonstrate that cold snaring can reduce polyp numbers in fap patients , anecdotally we also commonly use cold snaring in the rectum or pouch of fap patients with low polyp burdens at surveillance examinations .
ablation using apc is commonly used in clinical practice to reduce polyp burdens in patients with fap after subtotal colectomy or total proctocolectomy .
apc is efficient and safe , and the senior author has extensive experience in its use in fap patients for colonic , ileal , and duodenal polyps .
anecdotally , we find that cold snaring is as efficient as apc in colorectal polyp obliteration in fap patients , particularly for polyps in the 4    10  mm size range .
such polyps often require multiple aimed short pulses of apc , or a longer sustained pulse of apc , but are eradicated in a single quick cut using the cold snare .
3  mm polyps with cold snaring seems sometimes to be more efficient with apc .
use of a stiff snare that improves tissue capture may improve the efficiency of cold snaring for tiny flat polyps .
thus , we find that cold snaring has generally comparable efficiency to apc in treating colorectal polyps in fap , and suspect it is at least as safe and effective as apc
. attempts to delay surgery in fap may be appropriately met with skepticism . in a study of 659 fap patients with subtotal colectomies ,
the risk of death from rectal cancer was 12.5  % by age 65 , and 75  % of patients with rectal cancer had a negative rectoscopy within 12 months of the diagnosis of rectal cancer 9 .
this report is inconsistent with our experience ( with fewer patients ) in that we have never seen a patient with fap progress to colorectal or pouch cancer during surveillance , and we rarely see a  negative  proctoscopy during surveillance of fap after subtotal colectomies . in almost all cases , at least a few diminutive polyps are encountered , and we resect or destroy these polyps .
our experience is more consistent with the report of gleeson et al . where only three of 42 fap patients with prior surgical treatment had neoplastic progression during endoscopic surveillance .
in that series , polyp destruction was achieved using a combination of snare polypectomy , apc , and nd : yag laser 8 .
we recommend that endoscopic examination during fap surveillance should be meticulous , should include large scale polyp resection or destruction , and that the number of treated polyps be counted ( and the size range recorded ) so that reduction of polyp can be documented at subsequent examination .
our results indicate that large scale cold snare polypectomy provides an effective approach to controlling polyp burden in selected fap patients , and can be considered a viable alternative to ablative techniques such as apc . because cold snare polypectomy is efficient ( and safe ) in its application ,
we recommend it as an approach to controlling polyp burden in selected individuals with fap .
background and study aims : familial adenomatous polyposis ( fap ) is generally managed by colectomy , but in some cases surgery is delayed and polyp burdens are managed endoscopically . 
 we aimed to describe the use of cold snare polypectomy to control the polyp burden in selected patients with fap . 
 
 patients and methods : this was a retrospective cohort study . 
 polyps were counted and the range of polyp size recorded at each examination . 
 patients with a reduction in polyp number and mean size were considered to have successful endoscopic reduction of their polyp burdens . 
 
 results : of 79 patients with fap , 21 had an attempt at delaying surgery by cold snaring of at least 30 adenomas , and had at least one follow - up at our institution . 
 ten patients had intact colons , 6 had intact rectums , and 5 had heavy polyp burdens in an ileo - anal pouch . among 
 the 21 patients , the mean number of polyps resected at the first examination was 85 , range 30    342 . 
 nineteen of 21 patients had fewer polyps at the second examination , and of those , only one had any persistence of adenomas   1  cm in size . during follow - up 
 , two patients underwent surgical resection and the remainder had reductions in their polyp burdens at follow - up endoscopy . 
 
 conclusions : cold snare polypectomy effectively reduces polyp burden in selected fap patients .