Introduction
Colorectal cancer (CRC) refers to tumors that develop in the large intestine (colon)
and rectum.[1] This condition is recognized as a significant public health issue worldwide.[2] In Brazil, CRC ranks third among the most common types of cancer, excluding non-melanoma
skin tumors.[3] The National Cancer Institute (INCA) estimates that between 2023 and 2025, there
will be 45,630 new cases of colorectal cancer per year in Brazil, representing an
estimated incidence rate of 21.10 cases per 100,000 inhabitants.[3]
The progression of colorectal cancer varies and is influenced by the complex interaction
between genetic and environmental factors.[4] The primary pathway of development, responsible for ∼75% of cases, is known as the
adenoma-carcinoma sequence, in which adenomatous polyps become malignant.[1]
[5] The development mechanism of the remaining CRC cases is not yet fully understood.[6]
Colorectal polyps, which are protrusions in the mucosa of the colon and rectum, play
a crucial role in CRC prevention when identified and removed early through polypectomy
during colonoscopy.[4]
[7] This approach interrupts the adenoma-carcinoma sequence by detecting lesions early,
reducing the incidence, morbidity, and mortality of the disease.[8] This highlights that colonoscopy not only provides a diagnosis but also plays an
essential therapeutic role.[4]
Colonoscopy is highly preferred as a diagnostic method and is often considered the
gold standard. Its advantage lies in its ability to examine the entire large intestine
and perform the removal or biopsy of polyps, including those with advanced or non-advanced
neoplasia.[7]
[8]
Considering the importance of early lesion identification for CRC treatment and prevention,
this study aims to analyze the profile of patients with colorectal polyps who underwent
colonoscopy at a reference clinic in the south region of Santa Catarina from January
to June 2023. This research contributes to a better understanding of the local epidemiology
of these lesions and identifies relevant clinical and morphological characteristics.
The findings may help improve colorectal cancer screening and prevention strategies
while assisting in identifying specific at-risk groups. The study's methodological
rigor, including compliance with the STROBE protocol and ethical approval, ensures
its clinical and scientific credibility and usefulness.
Methods
A cross-sectional, descriptive study was conducted with the collection of secondary
data to analyze the profile of patients with colorectal polyps detected in colonoscopies,
following the steps recommended by the STROBE (Strengthening the Reporting of Observational
Studies in Epidemiology) protocol. All procedures were approved by the Research Ethics
Committee (CEP) of the Federal University of Santa Catarina (UFSC), according to the
Ethical Appreciation Presentation Certificate (CAAE) N°. 73561923.6.0000.012.
The analyzed data were obtained from medical records of a reference clinic located
in the south region of Santa Catarina, concerning examinations performed between January
and June 2023. Inclusion criteria considered patients over 18 years of age, of both
sexes, who underwent a complete colonoscopy within the selected period. Cases were
excluded from the sample if colonoscopy reports were incomplete or inconclusive due
to technical reasons, inadequate bowel preparation, colon obstruction, intestinal
loop obstruction, a history of previous colorectal cancer, or if they involved patients
under 18 years old, those whose clinical data could not be retrieved from medical
records or had missing data, and exams in which no polyps were detected.
The analyzed variables included sex, age, indication for the procedure, bowel preparation
quality (according to the Boston Bowel Preparation Scale - BBPS),[9] polyp morphology, as well as polyp size, number, topographic distribution, and method
of extraction. The reasons for the procedure were categorized as screening for colorectal
cancer, anemia, polypectomy, positive fecal occult blood test (FOBT), hematochezia,
lesion surveillance, abdominal pain or distension, diarrhea, constipation, weight
loss, altered bowel habits, and “others.” The “others” category included the following
indications: presence of hemorrhoids, pain during defecation, evaluation of ulcerative
colitis, assessment of cecal blurring, family history of colon cancer, and rectal
pain. Indications were categorized this way to group those with lower statistical
relevance.
The topographic categories used were cecum, ascending colon, transverse colon, descending
colon, sigmoid, and rectum. Similarly, bowel preparation quality according to BBPS
was divided into good preparation and unsatisfactory preparation. For epidemiological
comparison purposes, the population was divided into three age groups: under 45 years
old, between 45 and 75 years old, and over 75 years old. Polyp morphology was classified
according to the Paris Classification for polypoid lesions (sessile, subpedunculated,
and pedunculated polyps).[10] Polyp size was categorized as small (<5 mm), medium (5–20 mm), and large (>20 mm).[2] The number of polyps was divided into 1, 2, 3, 4, and 5 or more lesions detected
in the same examination. The extraction method was classified as biopsy forceps, diathermy
loop, and cases where polyps were not removed.
Initially, a description of the sample was performed according to the sociodemographic
and clinical characteristics of the patients, using absolute and relative frequencies
for categorical variables and means and standard deviations (SD) for numerical variables.
Additionally, using the same parameters, the main indications for the examination
were described. Furthermore, the association between the number of lesions and independent
variables was tested. Considering the number of polyps as the unit of analysis, their
morphology was described according to topography, size, and extraction type. To test
these associations, Pearson's Chi-square test was used, and when appropriate, Fisher's
exact test. The analyses were performed using statistical software Stata 16.1.
Results
During the analyzed period, a total of 667 colonoscopies were performed, of which
206 were selected after applying the eligibility criteria. Among the selected examinations,
the majority were performed on female patients (58.7%). The mean age of the patients
was 60.5 years, ranging from 32 to 90 years. Most colonoscopic examinations were conducted
in patients aged between 45 and 75 years (83.0%), followed by patients under 45 years
old (9.2%). The complete data can be observed in [Table 1].
Table 1
Sample description
|
Variables
|
n
|
%
|
|
Sex
|
|
|
|
Male
|
85
|
41,3
|
|
Female
|
121
|
58,7
|
|
Age (years) (mean/ standard deviation)
|
|
|
|
< 45
|
19
|
9,2
|
|
45 to 75
|
171
|
83,0
|
|
> 75
|
16
|
7,8
|
|
Bowel preparation (Boston)
|
|
|
|
Good
|
190
|
92,2
|
|
Unsatisfactory
|
16
|
7,8
|
|
Indication
|
|
|
|
Screening
|
123
|
59,7
|
|
Other
|
83
|
40,3
|
|
Number of lesions
|
|
|
|
1
|
111
|
54,0
|
|
2
|
52
|
25,2
|
|
3
|
20
|
9,7
|
|
4
|
10
|
4,8
|
|
5 or more
|
13
|
6,3
|
Source: prepared by the authors.
Regarding bowel preparation, according to the Boston scale, 92.2% of the examinations
showed adequate preparation for the procedure. As for the indications for performing
the exam, the majority were for colorectal cancer screening (59.7%) ([Table 1]). Other indications included, in second place, constipation (5,8%). The third most
common indication was hematochezia (4,4%). The remaining indications are detailed
in [Table 2].
Table 2
Description of colonoscopy indication
|
Indication
|
n
|
%
|
|
Screening
|
123
|
59,7
|
|
Anemia
|
8
|
3,9
|
|
Polypectomy
|
8
|
3,9
|
|
Positive Fecal Occult Blood Test (FBS)
|
6
|
2,9
|
|
Hematochezia
|
9
|
4,4
|
|
Monitoring of lesions
|
8
|
3,9
|
|
Abdominal pain or distensions
|
8
|
3,9
|
|
Diarrhea
|
7
|
3,4
|
|
Constipation
|
12
|
5,8
|
|
Weight loss
|
2
|
0,9
|
|
Change in bowel habits
|
3
|
1,5
|
|
Others
|
12
|
5,8
|
Source: prepared by the authors.
Regarding the number of lesions identified in a single colonoscopic examination, many
cases presented a single polyp (54.0%).
It was observed that 10.6% of men had 5 or more lesions, while only 3.3% of women
presented this quantity. However, there was no statistically significant difference
in the total number of lesions found between sexes (p = 0.057).
No patient under 45 years old had more than 3 lesions, while 5.8% of patients between
45 and 75 years old and 18.7% of patients over 75 years old had 5 or more lesions.
Patients between 45 and 75 years old had the highest percentage of examinations with
3 lesions, whereas patients over 75 years old had the highest percentage of examinations
with 4 lesions and with 5 or more lesions (p = 0.002). There was no statistically significant difference in the number of lesions
concerning bowel preparation (p = 0.965) or the indication for the examination (p = 0.840) ([Table 3]).
Table 3
Characterization of the number of polyps
|
Number of injuries
|
|
Variables
|
1
|
2
|
3
|
4
|
5 or more
|
p-value
|
|
Sex
|
|
|
|
|
|
0,057
|
|
Male
|
51,8
|
20,0
|
14,1
|
3,5
|
10,6
|
|
|
Female
|
55,3
|
29,0
|
6,6
|
5,8
|
3,3
|
|
|
Age (years)
|
|
|
|
|
|
0,002
|
|
< 45
|
73,7
|
21,0
|
5,3
|
0,0
|
0,0
|
|
|
45 to 75
|
53,2
|
27,0
|
10,5
|
3,5
|
5,8
|
|
|
> 75
|
37,5
|
12,5
|
6,3
|
25,0
|
18,7
|
|
|
Bowel preparation
|
|
|
|
|
|
0,965
|
|
Good
|
54,2
|
24,7
|
10,0
|
4,8
|
6,3
|
|
|
Unsatisfactory
|
50,2
|
31,2
|
6,2
|
6,2
|
6,2
|
|
|
Indication
|
|
|
|
|
|
0,840
|
|
Screening
|
56,1
|
23,6
|
8,9
|
5,7
|
5,7
|
|
|
Others
|
50,6
|
27,7
|
10,9
|
3,6
|
7,2
|
|
Source: prepared by the authors.
[Table 4] presents the relationship between polyp morphology, distribution, size, and extraction
method, with a total of 408 polyps identified during the analysis.
Table 4
Distribution of polyps
|
n
(%)
|
Sessile (%)
|
Subpediculated (%)
|
Pediculated (%)
|
P-value
|
|
Location
|
|
|
|
|
0,002
|
|
Cecum
|
26 (6,4)
|
100
|
0
|
0
|
|
|
Ascending Colon
|
85 (20,8)
|
88,2
|
5,9
|
5,9
|
|
|
Transverse Colon
|
49 (12,0)
|
85,7
|
8,2
|
6,1
|
|
|
Descending Colon
|
59 (14,5)
|
88,2
|
6,8
|
5,0
|
|
|
Sigmoid Colon
|
99 (24,2)
|
68,7
|
13,1
|
18,2
|
|
|
Rectum
|
90 (22,1)
|
78,9
|
4,4
|
16,7
|
|
|
Size
|
|
|
|
|
<0.001
|
|
Small
|
209 (71,1)
|
97,2
|
1,4
|
1,4
|
|
|
Medium
|
101 (24,7)
|
49,5
|
25,7
|
24,8
|
|
|
Large
|
17 (4,2)
|
11,8
|
0,0
|
88,2
|
|
|
Extration
|
|
|
|
|
<0.001
|
|
Biopsy clamp
|
307 (75,2)
|
97,4
|
1,9
|
0,7
|
|
|
Diathermic loop
|
64 (15,7)
|
35,9
|
32,8
|
21,3
|
|
|
Not extracted
|
37 (9,1)
|
32,4
|
8,1
|
59,5
|
|
|
TOTAL
|
n = 408
|
n = 334
|
n = 30
|
n = 44
|
|
Source: prepared by the authors.
Regarding location, there was considerable variability across different segments of
the colon. The sigmoid colon was the most frequent site for polyp identification (24.2%),
followed by the rectum (22,1%) and the ascending colon (20,8%). In the cecum, all
identified polyps were classified as sessile, representing 100% of the total. This
morphology predominated throughout the colon and rectum. The highest proportion of
subpedunculated and pedunculated polyps was found in the sigmoid colon, with 13.1%
and 18.2%, respectively. In the rectum, the second highest proportion was of pedunculated
polyps (16.7%), while in the transverse colon, it was subpedunculated polyps (8.2%).
Regarding polyp size, the majority were classified as small (71.1%). Among small and
medium-sized polyps, sessile morphology was predominant, representing 97.2% and 49.5%,
respectively. No large polyps were classified as subpedunculated. Among large polyps,
the majority were pedunculated (88.2%).
The analysis of extraction methods revealed that biopsy forceps were the most used
method (75.2%), followed by diathermic loop (15.7%). Both extraction methods were
predominantly employed for the removal of sessile polyps, representing 97.4% and 35.9%,
respectively. Notably, 59.5% of pedunculated polyps were not removed.
Discussion
Colonoscopy is widely recognized for its high sensitivity in detecting cancer and
precancerous lesions, enabling simultaneous diagnosis and treatment.[11] Colonoscopic polypectomy plays a crucial role in reducing colorectal cancer incidence,
reinforcing the adenoma-carcinoma sequence theory, as demonstrated in prior studies.[12]
[13]
Our analysis revealed that many patients diagnosed with colorectal polyps were women,
comprising 58.7% of the sample. While statistical significance was not observed, the
literature suggests a slight female predominance in similar studies[1]
[5]
[8]
[14]
[15]
[16]
[17] Data from the National Cancer Institute's 2023 census projected 21,970 new cases
among men and 23,660 among women, with estimated risks of 20.78 and 21.41 new cases
per 100,000 individuals, respectively.[3]
Despite this, the absolute difference between sexes in our sample was 36 individuals
(17.4%), suggesting that prevention campaigns may increase awareness among men regarding
early detection. However, women continue to seek medical care more frequently, contributing
to a higher diagnosis rate of colorectal polyps, even though men exhibit a greater
lesion incidence.
In assessing sex and polyp count per examination, no statistically significant differences
emerged.[2] However, men presented a higher frequency of multiple polyps, with five or more
lesions in 10.6% of cases. These findings align with previous studies[2] indicating an increased prevalence of polyps with age, particularly after 50[2]
[5]
[8]
[14]
[18]
, affecting nearly 25% of individuals over 75.[2]
[11] In our cohort, spanning ages 32 to 90, 83% of polyp-positive cases were aged 45–75,
with a mean age of 60.5 years.
Notably, a considerable proportion of polyp cases occurred in individuals under 45,
reflecting a rising concern within the medical community regarding increased incidence
in younger populations.[1]
[4]
[12] Wolf et al.[19] linked this trend to Western lifestyle factors, including alcohol and red meat consumption,
obesity, smoking, low fiber intake, and physical inactivity.
Polyp count per colonoscopy varies among studies,[5]
[14] with reports of synchronous polyps ranging from 18.9% to 37.4%.[14] In our sample, most examinations revealed a single lesion (54.0%). Further analysis
showed that age correlated with lesion quantity; among patients over 75, 18.7% exhibited
five or more lesions, while those under 45 had a maximum of three. The predominance
of single-polyp findings in our study may be attributed to the younger demographic
composition of our sample.
Bowel preparation quality significantly impacts lesion detection, and our study found
that most patients had good preparation, with only 7.8% classified as inadequate.
Proper cleansing enhances the detection of lesions over 5mm,[4] whereas inadequate preparation increases the risk of missed diagnoses, incomplete
exams, and the need for repeat procedures.[4]
Regarding the indication for the examination, the results obtained in this study do
not differ significantly from those found in the literature. Although the literature
highlights intestinal bleeding (including rectal bleeding) as the main indication[8]
[13]
[17] our study revealed that the primary indication was screening, accounting for 59,7%
of the cases. However, it is important to note that in our investigation, intestinal
bleeding was still a significant indication, ranking third with 4,4% of the cases.
Moreover, the study was conducted in a private clinic, which may justify the higher
number of examinations related to screening rather than specific complaints. In private
healthcare settings, it is common for patients to have greater access to preventive
and routine tests, which may lead to a predominance of screening indications compared
to public settings, where examinations are more often sought due to specific symptoms.
Torres et al.[8] indicated that constipation ranked fifth in terms of indication frequency. However,
our research found constipation to be the second most frequent indication, suggesting
a difference in trends regarding reasons for undergoing the exam. This discrepancy
may be attributed to the specific profile of patients residing in the southernmost
region of Santa Catarina, their health and lifestyle patterns, and the fact that our
study was carried out in a private clinic. Additionally, Santos et al.[16] reported anemia as one of the main indications for colonoscopy, which is consistent
with the findings of our study, where it was the fourth most common indication.
Regarding topography, older studies revealed that the highest incidence of polyps
occurred in the sigmoid colon and rectum[1]
[5]
[14]
[16]
[17]
[19]. Our results showed that the sigmoid colon was the most frequent site for polyp
identification (24,2%), followed by the rectum (22,1%) and the ascending colon (20,8%).
Recent studies have observed an increasing trend in the occurrence of polypoid lesions
in the right colon, which aligns with our findings[2]
[7]
[20]
[21]
[22]. These findings highlight the importance of a complete colonoscopy, avoiding limitations
to the evaluation of the left colon, since approximately 23% of lesions may be located
near the splenic flexure and could be missed if the evaluation is restricted[20].
Most lesions in our study were sessile, corroborating previous findings.[5]
[7]
[14]
[18] Regarding morphology and topographic distribution, we observed that in the cecum,
100% of the polyps were sessile, with this morphology also being predominant throughout
the colon and rectum. In the sigmoid colon, although sessile polyps prevailed, 13.1%
were subpedunculated, and 18.2% were pedunculated. In the rectum, sessile polyps were
the most frequent, followed by pedunculated ones (16.7%). Authors such as Manzione
et al.[14] also observed a predominance of sessile polyps in the sigmoid colon and rectum.[5]
[14]
[17]
Pedunculated polyps were most frequently found in the sigmoid colon, followed by the
rectum, while subpedunculated polyps were predominantly located in the sigmoid colon
and, subsequently, in the transverse colon. These findings are important because distal
polyps are closely associated with advanced proximal neoplasia.[14]
The majority of polyps identified in this study were small in size (71.1%), which
is consistent with reports in the literature.[14]
[18] Both small and medium-sized polyps were predominantly sessile, representing 97.2%
and 49.5%, respectively, which is in agreement with findings from other studies.[7]
[18] These findings suggest a potential correlation between polyp size and the degree
of dysplasia, indicating that even small polyps may present significant dysplasia.[14]
Regarding large polyps, most were pedunculated (88.2%), and no large polyps were classified
as subpedunculated. Gomes et al.5 also observed an association between polyp size
and the likelihood of being an adenomatous polyp, suggesting that the larger the polyp,
the higher the probability of it being an adenoma.
At the clinic studied, 9.1% of the total sample of polyps were not removed, with the
majority of these being pedunculated (59.5%). This may be attributed to the clinic's
role as a referral center for patients from the public healthcare system (SUS). In
some cases, patients need to be referred to larger centers with more complex and costly
equipment, especially for the removal of pedunculated and large polyps.[5]
Additionally, some polyps were not removed due to financial constraints among private
patients, lack of authorization for resection from the patient or family members,
the need for additional examinations, or the necessity of suspending anticoagulant
medications before the procedure.
It is important to emphasize that there is a consensus recommending polypectomies
for all symptomatic patients with polyps, regardless of morphology, if removal is
technically feasible,[5]
[18] except for polyps with hyperplastic characteristics.
The selection of the polyp removal method should be based on a thorough analysis of
its size, morphology, and location.[17] In our study, biopsy forceps were the most frequently used instrument, accounting
for 75.2% of removals, compared with electrocautery snare use, which represented 15.7%.
This can be explained by the size of the lesions found in our study, as biopsy forceps
are recommended for lesions up to 10mm,[24] in addition to the fact that most lesions identified were small or medium-sized
sessile polyps. The extraction methods are in accordance with the guidelines of the
Brazilian Society of Digestive Endoscopy (SOBED).
Although this was the first study to evaluate the profile of the population undergoing
colonoscopy in our region and had a significant sample size, some inherent limitations
must be acknowledged. One of them is the lack of access to histopathological results,
which could enrich the understanding of the histological characteristics of the polyps,
complementing the endoscopic findings.
A significant contribution of this study is highlighting a gap in scientific literature:
the scarcity of studies directly relating polyp morphology to their specific location
in the colon. This observation underscores the importance of our research in providing
valuable insights into the distribution of colorectal polyps according to their morphological
characteristics.
Furthermore, our results have potential implications not only for academic research
but also for clinical practice and public health. This study contributes to a better
understanding of the local population profile, enabling the observation of polyp migration
to the right colon and correlating morphological types with lesion location.
Finally, when analyzing the influence of colorectal cancer awareness policies, we
found that, although the female population was more prevalent, the absolute difference
was only 36 women. This suggests that prevention campaigns are beginning to raise
awareness among men, leading to an increased number of examinations and diagnoses
in this population.
