J Gastroenterol 2000 May;95(5):1147-51
to colon polyps in the elderly.
KM, Waye JD
of Gastroenterology, Mount Sinai Hospital, New York, New York, USA.
cancer is a common but potentially preventable disease. Nearly all
colorectal cancers are thought to arise from adenomatous polyps. The
conclusions from the National Polyp Study strongly support the concept
that the removal of polyps may prevent the future development of
colorectal cancer. With the growing acceptance of screening for colorectal
cancer, many elderly patients with adenomatous polyps will be discovered.
Because increasing age is a powerful determinant of a higher prevalence of
colonic neoplasia in asymptomatic individuals, physicians will need to be
prepared to make informed decisions regarding the treatment of elderly
patients with colonic polyps. The literature is reviewed and guidelines
are formed regarding the optimal surveillance interval for patients with
colonic polyps. The age at which surveillance and screening for colorectal
neoplasia should stop is also reviewed. Conclusions are
based on the currently available data.
polyps and cancer.
University Hospital, Denmark.
important studies on screening for colorectal neoplasia were published in
1998-99, including average-risk as well as high-risk groups, and different
strategies such as endoscopy, fecal occult blood tests, and other more
specific markers of neoplasia. Some of these studies included the use of
interventions other than initial screening and polypectomy; a few dealt
with diagnostic methods in symptomatic patients, and the new diagnostic
tool of virtual colonoscopy was highlighted by several authors. Endoscopic
treatment for large adenomas and early colorectal cancer has become more
widespread, but clearly it has limitations. Current discussion of the
topic of colorectal polyps and cancer is largely based on the concept of
the adenoma-carcinoma sequence, which is thought to be the most probable
pathogenesis for colorectal cancer.
Engl J Med 2000 Jun 29;342(26):1960-8
of colorectal cancer.
PA, Mayer RJ
of Adult Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
1999 Nov 27;354(9193):1873-4. [Texto
hyperplastic polyps and risk of recurrence of adenomas and hyperplastic
polyps.(Statistical Data Included)
Steven P Bensen, Bernard F
Cole, Leila A Mott, John A Baron, Robert S Sandler, Robert Haile, for the
Polyps Prevention Study Group
Am Coll Surg 1999 May;188(5):503-7
RJ, Simmang CL
of Surgery, University of Texas Southwestern Medical Center, Dallas
Although the syndrome of familial adenomatous polyposis is well known,
sporadic patients with multiple polyposis are rare. There are no known
syndromes associated with hyperplastic polyposis. In our search of the
English surgical literature, we find no reference to a
hyperplastic-adenomatous polyposis syndrome. STUDY DESIGN: Over a 3-year
period, we identified six patients ages 41 to 75 (mean age 61) with 50 to
100 hyperplastic polyps associated with adenomas. RESULTS: Most of the
hyperplastic polyps were found in the left colon and the largest ranged in
size from 6 mm to 18 mm. The larger polyps were clinically
indistinguishable from adenomas. Three of our six
patients had invasive cancer of the proximal colon. All tumors were
confined to the bowel wall. There was a family history of colon cancer in
only one patient and no family history of polyposis. CONCLUSION: These
patients differ from previously described patients with polyposis
syndromes; hyperplastic-adenomatous polyposis syndrome (HAPS) occurs in an
older population with no family history of polyposis, has fewer polyps,
most of which are hyperplastic, and is strongly associated with
adenocarcinoma of the colon. In this series, we describe a previously
unreported hyperplastic - adenomatous polyposis syndrome.
of reported cases
J Med 1999 Jan 25;106(1A):38S-42S
bran fiber and development of adenomatous polyps: evidence from
randomized, controlled clinical trials.
of Gastroenterology, Royal Melbourne Hospital, Victoria, Australia.
in oncogenes and tumor suppressor genes are thought to initiate and
promote the pathway to colorectal cancer, leading to hyperproliferation,
the development of adenomas, and progression to gross malignancy.
Intervention at any of these steps can potentially prevent the development
of cancer. Several
randomized, controlled trials have investigated the effect of dietary
interventions, including the addition of wheat bran fiber, on the
development of adenomatous polyps. In a familial adenomatous polyposis
trial, patients were treated with 4 g of ascorbic acid plus 400 mg of
alpha-tocopherol per day alone or with a grain fiber supplement (22.5
g/day) over a 4-year period. On an actual-intake basis, the combined
intervention inhibited the development of rectal polyps. However, the
Toronto Polyp Prevention Trial found no significant differences in polyp
recurrence rates between patients who were counseled to follow a low-fat,
high-fiber diet and patients consuming a typical Western diet with placebo
fiber. A 9-month study of patients with resected colon adenomas found that
dietary wheat bran fiber significantly reduced total, primary, and
secondary fecal bile acid concentrations and excretion rates. Such bile
acid levels are thought to be related to the risk of developing cancer.
The Australian Polyp Prevention Project reported that the combination of
fat reduction and a supplement of wheat bran reduced the incidence of
large colorectal adenomas. These latter results suggest that intervention
with a low-fat wheat bran supplemented diet inhibits the transition from
smaller to larger adenomas, which may be a critical step in determining
which adenomas progress to malignancy.
polyps and cancer.
Section, Minneapolis Veterans' Association Medical Center and University
of Minnesota, 55417, USA.
number of recent publications dealing with colon polyps and cancer
emphasize cost-effectiveness and the outcomes of screening and follow-up
surveillance of high-risk groups. These groups include patients with
either a past personal history or a family history of colorectal adenomas
or cancer. Several papers address the effectiveness and compliance with
different methods of screening of the asymptomatic, average-risk
population for colorectal neoplasia. Other important publications deal
with colorectal cancer prevention, the natural history of the
adenoma-carcinoma sequence, diagnosis of polyps and cancer, colonoscopic
polypectomy, management of the patient with a malignant polyp, and
endoscopic treatment of obstructing cancer.
J Gastroenterol 1998 Apr;93(4):619-22
polyps: experience of 236 Indian children.
U, Thapa BR, Vaiphei K, Singh K
of Gastroenterology and Pathology, Postgraduate Institute of Medical
Education and Research, Chandigarh, India.
We studied the clinical spectrum, histology, and malignant potential of
colonic polyps in Indian children (< or =12 yr). METHODS: Two hundred
thirty-six children with colonic polyps were studied from January 1991 to
October 1996. They were evaluated clinically and colonoscopic polypectomy
was done. Children with five or more juvenile polyps were labeled as
having juvenile polyposis and serial colonoscopic polypectomies were done
every 3 wk. Colectomy was performed when there were intractable symptoms
or clearing of the polyps by colonoscopy was not possible. Histological
examination of the polyps was done. Follow-up colonoscopy was done in
children with juvenile polyposis only. RESULTS: The mean age of these
children was 6.12 +/- 2.7 yr, with a male preponderance (3.5:1). Rectal
bleeding of a mean duration of 14 +/- 16 months was the presenting symptom
in 98.7%. Solitary polyps were seen in 76%, multiple polyps in 16.5%, and
juvenile polyposis in 7% (n = 17) of the children. A majority (93%) of the
polyps were juvenile and 85% were rectosigmoid in location. Adenomatous
changes, seen in 11%, were more common in juvenile polyposis (59%) than in
juvenile polyps (5%). Among those with juvenile polyposis, colon clearance
was achieved in eight, six required colectomy for intractable symptoms,
and three were still on the polypectomy program. Polyps recurred in 5% of
children with juvenile polyps and 37.5% of those with juvenile polyposis.
CONCLUSIONS: Juvenile polyps remain the most common colonic polyps in
children. A significant number of cases of polyps are multiple and
proximally located, which emphasizes the need for total colonoscopy in
all. Juvenile polyps should be removed even if asymptomatic because of
their neoplastic potential. Colonoscopic polypectomy is effective even in
juvenile polyposis. Surveillance colonoscopy is required in juvenile
Clin North Am 1997 Mar;26(1):1-17
polyps and their relationship to cancer.
EC, Lance P
of Medicine, State University of New York at Buffalo, USA.
dominant, familial forms of colorectal adenocarcinoma are recognized, but
more than 90% of cases are sporadic. Most familial and sporadic cases
arise through malignant transformation of benign adenomas in a process
known as the adenoma-to-carcinoma sequence. Adenomas are classified
histologically as tubular, tubulovillous, or villous. As a neoplasm,
adenomas all manifest mild, moderate, or severe dysplasia. The majority
(> 90%) of adenomas are small (< 1 cm in diameter) and do not
progress. Risk factors for carcinomatous progression include the presence
of multiple adenomas, size greater than or equal to 1 cm, and villous
histology or severe dysplasia in adenomas of any size. The
adenoma-to-carcinoma sequence advances through the accumulation of lesions
involving multiple genes. It appears that similar molecular genetic
mechanisms are involved in familial and sporadic forms of colorectal
Colon Rectum 1997 Aug;40(8):929-34
survival after treatment of malignant colonic polyps.
C, Gathright JB Jr, Hebert SJ, Beck DE, Opelka FG, Timmcke AE, Hicks TC
of Colon and Rectal Surgery, Ochsner Clinic, New Orleans, Louisiana 70121,
This study was designed to evaluate the long-term outcome and survival of
patients treated for malignant colonic polyps. METHODS: A retrospective
review of 15,975 cases of colonoscopies with 8,685 endoscopic
polypectomies performed between 1972 and 1990 was undertaken. In 65
patients, the polypectomy specimens contained invasive carcinoma. Six
patients were excluded (follow-up, <6 months). Polyp data, operative
findings, and follow-up on the remaining 59 patients were recorded.
RESULTS: Malignant polyps were found in 35 males and 24 females who had an
average age of 64 (range, 39-81) years. Follow-up ranged from 12 to 202
(mean, 90) months. Tumor differentiation was poor in one and well or
moderately differentiated in 58 patients. Positive or indeterminate
margins were found in 13 patients. Thirty-seven (63 percent) patients were
managed with polypectomy and surveillance. Four of these (with rectal
tumors) also had an additional local excision for questionable margins.
One recurrence was noted in a patient who refused surgery, which was
recommended because of indeterminate margins. Twenty-two patients (37
percent) underwent colectomy. Indications included Haggitt Level 3 or 4
invasion (19), inadequate margins (7), patient preference (1), and poor
differentiation (1). Residual disease was found in colectomy specimens of
three patients (14 percent). There were no cancer-related deaths in either
treatment group. Life table analysis demonstrated a five-year survival of
82 percent for the colectomy group and 95 percent for the polypectomy
group (P = 0.15). CONCLUSION: Treatment of patients with malignant polyps
must be individualized based on evolving criteria. Patients in whom
polypectomy margins are inadequate should undergo colectomy. With
appropriate selection criteria, patients selected for colectomy had a
five-year survival rate similar to the rate of those treated by
Intern Med 1993 Oct 15;119(8):836-43
erratum appears in Ann Intern Med 1994 Feb;15;120(4):347
guideline: diagnosis, treatment, and surveillance for patients with
nonfamilial colorectal polyps. The Practice Parameters Committee of the
American College of Gastroenterology.
College of Gastroenterology, Arlington, VA 22206-1656.
To outline the preferable approach to the management of patients with
nonfamilial colorectal polyps. DATA SOURCES: The human subject English
language literature for the past 15 years, searched using MEDLINE and the
terms "polyp-," "adenoma-," and
"polypectomy-colorectal." STUDY SELECTION: The titles and
abstracts of all pertinent articles were reviewed. All randomized
controlled trials and large case-control and cohort studies related to
colorectal polyps were reviewed in depth. DATA SYNTHESIS: Evidence was
evaluated along a hierarchy with randomized controlled trials receiving
the greatest weight. Conclusions and recommendations were reviewed by a
large group of experts in gastroenterology, radiology, and pathology and
were circulated for comment to primary care medical societies.
CONCLUSIONS: Most patients with polyps should undergo colonoscopy to
excise the polyp and search for synchronous neoplasms. Small polyps (<
0.5 cm) require individualization. A hyperplastic polyp found during
proctosigmoidoscopy is not an indication for colonoscopy. Large sessile
polyps require careful follow-up to ensure complete resection. The need
for further treatment of a resected polyp with invasive carcinoma depends
on several well-defined clinical and pathologic criteria. Follow-up
surveillance after polypectomy should be tailored to the individual risk
assessment for each patient. Initial follow-up should be performed at 3
years for most postpolypectomy patients. After one negative result of a
3-year examination, the interval can be increased to 5 years. Patients
with one small tubular adenoma do not have an increased risk for cancer,
and therefore follow-up surveillance may not be indicated. Adoption of
these recommendations should substantially reduce the cost of
postpolypectomy surveillance and of screening for colorectal cancer.
1992 Sep 1;70(5 Suppl):1236-45
National Polyp Study. Design, methods, and characteristics of patients
with newly diagnosed polyps. The National Polyp Study Workgroup.
SJ, Zauber AG, O'Brien MJ, Gottlieb LS, Sternberg SS, Stewart ET, Bond JH,
Schapiro M, Panish JF, Waye JD, et al
Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center,
New York, NY 10021.
National Polyp Study (NPS) is a multicenter prospective randomized trial
designed to evaluate follow-up surveillance strategies in patients who
have undergone polypectomy for the control of large bowel cancer. The
study design was developed by a joint research committee from American
Gastroenterological Association, the American Society for Gastrointestinal
Endoscopy, and the American College of Gastroenterology. Subjects who met
the eligibility criteria were randomized into two different treatment
arms. Eligibility criteria included: removal of one or more adenomas;
complete colonoscopy; no prior polypectomy, inflammatory bowel disease, or
familial polyposis; and no history of colon cancer. The treatment arms
consisted of a frequent follow-up (1 and 3 years after initial
polypectomy) and a less frequent follow-up (3 years). Follow-up
examinations included fecal occult blood tests, air-contrast barium enema,
and colonoscopy. The latter was done on 9112 referred patients at the
seven participating centers from November 1980 until February 1990 who had
no history of polypectomy, colon cancer, familial polyposis, or
inflammatory bowel disease. Of these patients, 4763 (52.3%) had no polyps;
549 (6.0%) had an invasive cancer; 776 (8.5%) had nonadenomatous polyps;
208 (2.3%) had incomplete examinations; 184 (2.0%) had other findings; and
2632 (28.9%) had one or more adenomas, of which 1418 (53.9%) were
randomized to one of the two treatment arms. This article reports the
background, rationale, objectives, methods, and organization of this study
and includes patient characteristics on initial
presentation. Future data provided by the NPS may help in the development
of recommendations for surveillance guidelines for such patients. This
study also provides a framework to address questions regarding the natural
history of adenomas and their relationship with colorectal cancer.