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196
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A. Fingerhut et al.
Fig. 18.3 Variations in the position of the ileocolic vessels [15]
The vascular problems of concern can arise
from the level of ligation of the inferior mesenteric artery (preservation or not of the left colic
artery), preservation or not of the superior rectal
artery, integrity of the arcade of Drummond,
Grifths’ point, Sudeck’s point, variations in the
anatomy of the MCA, and problems created
when patients have atherosclerosis, or have had
18 Vascular Problems Related to Colectomy: Habitual and Variant Anatomy, Prevention, and Tactical…
197
chemotherapy/radiation therapy (in particular
within the previous 6 months), embolization
(colonic bleeding) or prior surgery (gastrectomy,
pancreatectomy, radial nephrectomy and in particular, previous colectomy), when the origins of
the main feeding vessels have been ligated (previous surgery), or are insufcient (atherosclerosis, median arcuate syndrome, previous radiation,
or when related to the direction of ow through
the vascular network.
Usually the colonic vascularization is not
affected by the median arcuate ligament syndrome [16]. However, when the hepatic vascularization is dependent on a right hepatic artery
arising from the superior mesenteric artery, or
when the celiac axis vascularization is dependent
on retrograde ow through the pancreaticoduodenal arcades, attention is warranted to correctly
identify the middle colic (and eventually the right
colic) vessels, remembering that the rst branch
off the SMA may be the inferior pancreaticoduodenal arcade, and that the origins of such aberrant
hepatic vascular supply may complicate the identication of the MC vessels.
Both the origins of the SMA and IMA can be
stenotic, usually due to atherosclerosis (intrinsic
stenosis). In case of stenosis of the origin of the
IMA, antegrade ow from the SMA through the
marginal arcade or when Grifths’ point is insufcient or absent through the proximal mesenteric
arcade, retrograde ow from the internal iliac
arterial ow originating from the middle and
inferior rectal arteries through the superior rectal
artery can be present and warrants attention when
division of the marginal arcade or the superior
rectal artery is envisioned.
In case of SMA stenosis, vascular supply is
taken up by the celiac axis via the pancreaticoduodenal arcades and jejunal arteries. Retrograde
ow also exists from the IMA through the proximal and peripheral marginal arcades.
When both the SMA and IMA are stenotic, the
colonic vascular supply is essentially based on
backow from the celiac axis through the pancreaticoduodenal arcades and jejunal arteries, and/
or, to a lesser degree, from the internal iliac arteries via Sudeck’s point.
The typically four-branched gastrocolic trunk
of Henle (right gastro-omental vein, right colic
vein, middle colic vein, and pancreaticoduodenal
vein) exists in about 8 out of 10 patients. Wide
variations exist, a gastrocolic trunk in one-third, a
gastro-pancreatic trunk in 10%, and a gastropancreatico- colic trunk in a little more than 50%.
18.3 Impact onColectomy
Under normal conditions (patient non atherosclerotic, no previous chemo/radiation therapy, no
prior colectomy), both left and right colectomies
are straightforward.
Transverse colectomy is a bit more tricky, as
the limits of resection depend on whether the
tumor is located in the left or right half of the transverse colon and the patency of the marginal artery
after division of one, both or the common trunk of
the MCA, or the Grifths’ point for vascularization coming from the left colic artery. The proximal segment is vascularized by the anastomoses
arising from the ascending branch of the ileocolic
artery for right-sided resections, and on the MCA
and the marginal artery for left- sided resections.
18.3.1 Left Colectomy
The vascular supply to the proximal and distal
segments to be anastomosed after left colectomy
depends on whether the colectomy is segmental
or a hemicolectomy. There is an ever-ongoing
debate as to whether it is better to perform a hightie (between the aorta and the left colic artery
run-off) or low-tie (below the left colic artery
run-off) ligation of the inferior mesenteric artery.
Protagonists for one or the other base their arguments on the theoretical radicality of high-tie
with regard to carcinologic principles or the extra
length procured for the proximal segment versus
those who argue that there is no statistically signicant difference in survival between the two, or
that extra length comes essentially from the ligation of the inferior mesenteric vein, more than the
arc of the left colic artery when left intact.
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A. Fingerhut et al.
18.3.2 Right Colectomy
For simple ileocecal resections, vascular variations or disease do not have notable consequences
on the vascular supply to the remaining terminal
ileum or the distal transverse colon.
The absence of the right colic artery has little
if any consequences on the outcome of rightsided colectomies.
Problems arise however, when the MCA is
absent, and the vascular supply to the right portion of the transverse colon and the hepatic exure is dependent on the marginal artery (blood
coming from the IMA via the left colic artery), or
the secondary arcades (Riolan or Moskowitz)
that must be preserved when the peripheral connection is absent or decient. This means that
lymph node dissection proximal to these arcades
has to be extravascular.
18.3.3 Colonic Resections inPatients
withVascular Disease
18.3.3.1 Left Colectomy
intheVascular Patient
The splenic exure vascular network can be a
problem as the risk of ischemia of the mobilized
colon is about 40% because of insufcient
upstream vascular supply from the middle colic
vessels through the Drummond arcade and the
right branch of the left colic artery (Grifths’
point). In these patients, one should consider
preservation of the left colic artery (this artery
may be the only source of splenic exure vascularization). Likewise, when present, a more proximal mesenteric arcade (Riolan or Moskowitz)
should be preserved (may be the only source of
blood supply to the transverse and right or left
colon).
Onset of ischemia of the left portion of the
transverse colon during segmental colectomy
dictates the need to extend the colectomy to a true
left hemicolectomy. In these cases, the proximal
colonic segment may be too short for a traditional
pre-mesenteric anastomosis and may then require
a trans-mesenteric anastomosis (Toupet tech-
nique) [17], sometimes called retro-mesenteric
anastomosis by Romberg or mobilization and
inversion of the entire right colon (Deloyers technique) [18, 19]. Of note, the trans-mesenteric
procedure requires full mobilization of the proximal transverse colon and that the MC vessels are
intact [20]. Patients with poor hemodynamics
during the procedure should not have an anastomosis and undergo a Hartmann procedure.
Patients with aortic bifurcation thrombosis
(Leriche syndrome) are at risk of lower limb
ischemia when there is no vascular intercommunication between the last sigmoid artery and the
superior rectal artery (Sudeck’s critical point) [9].
These patients require a revascularization of their
lower limbs prior to colonic surgery, or if this is
not possible or done, the vascular division of the
colonic mesentery should be performed as close
as possible to the intestinal wall.
18.3.3.2 Right Colectomy
inthePatient with
Vascular Disease
For patients requiring a right colectomy including the hepatic exure, the MCA must be preserved to avoid devascularization of the left
transverse colon. If this is not possible and ischemia onsets, total colectomy may be the only
solution.
18.3.4 Consequences ofPrevious
Surgery
18.3.4.1 Left Colectomy inaPatient
withPrevious Right
Colectomy
In patients scheduled for left colectomy but who
have already undergone a right colectomy, it is
important to know whether or not the middle
colic and/or the right colic arteries were preserved or not. Preoperative vascular mapping
may be necessary. If one or both of these arteries
were not preserved, and/or the patient requires a
more extensive colectomy, it is imperative that
the left colic artery be preserved. If this is not
possible, then a total colectomy is needed [9].
18 Vascular Problems Related to Colectomy: Habitual and Variant Anatomy, Prevention, and Tactical…
199
18.3.4.2 Right Colectomy
inaPatient with
Previous Left Colectomy
Ileocecal resection for cecal carcinoma with
preservation of the hepatic exure can usually be
performed safely as long as the middle colic vessels or a left colonic artery and marginal arcade
are intact. This determines whether the remaining
transverse colon can be preserved or not. If the
middle colic and/or the right colic artery are not
intact, total colectomy with ileorectal anastomosis is required [9].
18.3.5 Strategy forOncologic Lymph
Node Dissection inPatients
withColonic Cancer
In patients who have had a previous colectomy
(right or left) and/or who have a history of vascular disease and must undergo colectomy for colon
cancer, the indications for lymph node dissection
must be carefully pondered case by case.
1. In a patient with previous colectomy but no
vascular disease, or with vascular disease but
without aortic bifurcation thrombosis (or
when surgical or endovascular extremity
revascularization is possible), oncological
rules should be observed including oncologically sound lymph node dissection.
2. In a patient with aortic bifurcation thrombosis
when lower extremity revascularization is not
possible, total colectomy must be envisioned.
18.4 Technical Aspects
As for any intestinal resection, tissue vascularization must be evaluated as the operation progresses. Whatever type of resection is proposed,
temporary vascular clamping at the proposed
ligation area should be performed prior to any
denitive mesenteric division, conrming the
persistence of a pulse distally, as detected by
direct palpation or Doppler probe. Similarly,
after arterial transection, intraoperative assessment of the junction between well- and poorly
vascularized bowel will help to identify the optimal level at which the colon should be divided.
This is where techniques currently under evaluation to assess the vascularization of the colon
(indocyanine green) or to assess lymph node
involvement and thereby limit the extent of node
dissection (indocyanine green, sentinel lymph
node technique) could be of major interest [21].
References
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2. Mike M, Kano N. Reappraisal of the vascular anatomy of the colon. Dig Surg. 2013;30:383–92.
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Prophylactic Resections
forGenetic Predisposition ofColon
andRectum
EmrahAkin, EmreGonullu, andFatihAltintoprak
19
19.1 Introduction
Prophylactic surgery aims to eliminate the target
organ before the life-threatening disease develops, to increase the expected survival and prevent
the decrease in the quality of life. Various etiologies can be candidates for prophylactic surgery.
The purpose of prophylactic surgery in diseases
of the colon and rectum with a genetic predisposition for malignancy is the excision of the organ
at risk before malignancy develops. In case of
detection of malignancy in the organ to be
resected, the name of the surgery will be denitive surgery, not prophylactic. In prophylactic
surgeries to be performed due to the risk of developing malignancy, oncological principles must
be applied, as in denitive operations.
Hereditary and familial colorectal polyposis
syndromes in the colon and rectum offer indications for prophylactic surgical interventions. The
hereditary colorectal syndromes discovered
about 100 years ago when Alfred S. Warthin
described Hereditary Non-polyposis Colorectal
Cancer Syndrome (HNPCC), which is now
E. Akin · E. Gonullu
Department of General Surgery, Sakarya University
Research and Educational Hospital, Sakarya, Turkey
e-mail: emrahakin@sakarya.edu.tr;
emregonullu@sakarya.edu.tr
F. Altintoprak (*)
Department of General Surgery, Faculty of Medicine,
Sakarya University, Sakarya, Turkey
e-mail: altintoprak@sakarya.edu.tr
known as Lynch Syndrome (LS) [1]. The molecular structure of the diseases was rst understood
by the report of the Familial Adenomatous
Polyposis Syndrome (FAP) by exposing the APC
gene located on the 5q chromosome Groden after
1990s [2]. Subsequently, respectively Lynch syndrome was identied by determining the MLH1/
MSH2/MSH6 mutations in 1993, Peutz–Jeghers
syndrome (PJS) was identied by determining
the STK11in 1998, and Juvenile Polyposis (JP)
syndrome was identied by determining SMAD4/
BMPR1A mutations in 2001 [3–6]. Although
there are some changes in nomenclature over
time due to different phenotypic, genotypic, histopathological and clinical presentations, it has
been preferred to categorize the syndromes based
on the polyp structure in the current literature.
Today, it will be more accurate to evaluate the
situations which are candidates for prophylactic
surgery, with the newly dened different subgroups (hereditary adenomatous polyposis syndromes, MUTYH associated polyposis,
polymerase-proofreading associated polyposis,
Lynch syndrome, familial colorectal cancer type
X, etc.) which surgical options may be performed, together.
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
O. N. Dilek et al. (eds.), Prophylactic Surgery, https://doi.org/10.1007/978-3-030-66853-2_19
201
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E. Akin et al.
19.2 Hereditary Adenomatous
Polyposis Syndromes
19.2.1 Familial Adenomatous
Polyposis Syndrome
It is characterized by more than 100 adenomatous polyps that become adenocarcinoma, the
incidence is 1/7000–12,000in newborn, and the
ratio of female/male is 1 [7]. Polyps mostly
appear in the second or third decade. The average
age of diagnosis is 36, and the average age for the
appearing rst polyp is 16 [8, 9]. Clinical presentation may be in three types: early childhood,
15–25years old, and late (mild) onset [10]. At the
time of diagnosis, 90% of polyps are smaller than
0.5cm, and less than 1% are larger than 1 cm.
Adenomas transform into cancer 100%.
Epidermoid cysts, osteoma in bone, desmoid
tumor, gastric fundic polyp, and congenital
hypertrophy of retinal pigment epithelium may
be seen as extra-colonic involvements of FAP
[11]. The variant accompanied by a brain tumor
and medulloblastoma is known as Turcot
Syndrome. The histopathological feature is that
they are dysplastic or adenomatous epithelial
cells seen in portions of single crypts that are not
found in polyps in the healthy population and are
called as microadenomas [7].
Genetic tests are carried out for making a
diagnosis in two situations:
1. For testing individuals with polyposis for
whom a clinical diagnosis is uncertain; indi-
viduals with more than 10 adenomas or some-
times with extra-colonic manifestations but no
underlying pathogenic mutation.
2. To the family of the individual with the known
germline mutation; while positive result pro-
vides the diagnosis of the syndrome, in a neg-
ative result, the syndrome is excluded.
In the case of suspected adenomatosis, APC
and MUTYH gene mutation analysis should be
performed [12]. In FAP, an allele is mutated;
adenoma formation occurs if the secondary
allele is damaged or deleted due to a somatic
event. Increased adenoma-carcinoma sequence
after APC reactivation is similar to K-ras, p53,
and chromosome 18 mutation in FAP and sporadic cancer. Although mutations are scattered
throughout the APC gene, most mutations appear
at the 5′ end of exon 15 called the cluster region
[13, 14].
Surveillance in affected families should be
initiated from puberty [15, 16]. Prophylactic surgery should be considered in the circumstances
such as severe polyposis burden, severe dysplasia, tubule-villous histopathology, multiple adenomas greater than 5mm and bleeding, diarrhea,
retarded growth, anemia, and severe stress [17].
Colectomy with or without proctectomy is recommended for the treatment. If the count of rectal adenoma is less than 20, the count of colonic
adenoma is less than 1000, and there are genetic
mutations between 1252 and 1464, proctectomy
may not be required [17]. Nevertheless, prophylactic surgery can be postponed in patients who
are well selected, whose adenomas are less than
5mm, who have a family history of aggressive
abdominal desmoid tumors, and who are entirely
asymptomatic, because complications related to
desmoid tumors can be more mortal than colorectal cancer development [18]. However, FAP
patients are generally operated in their 20s, and
as a result of this strategy, desmoid tumors and
upper gastrointestinal system (GIS) cancers are
among the causes of mortality and morbidity in
these patients [19].
Desmoids are non-metastatic locally invasive
myobroblastic proliferations, and although they
can be settled in any localization, they occur
especially in the small intestine mesentery and
abdominal wall in patients with FAP. Intraabdominal desmoids can lead to urological or
intestinal obstruction and sometimes undergo
necrosis [20]. In FAP patients, 80% of desmoids
occur until 35years of age, on average 3.2years
after prophylactic surgery of the large intestine
(min 6months, max. 9years) [21]. According to
this study, routine imaging is not performed for
desmoids.
Upper GIS polyps are most common in the
periampullary region, and follow-up of patients
should begin with endoscopy and biopsy of suspected polyps at the age of 25–30. Although
19 Prophylactic Resections forGenetic Predisposition ofColon andRectum
203
options are endoscopic mucosal resection, snare
ampullectomy or trans-duodenal excisions, endoscopic ablation generally requires a large number
of sessions, and recurrence is high after all of
three [22]. For papillary or duodenal adenomas
with persistent or recurrent high-grade dysplasia,
pancreas-preserving duodenectomy or pancreaticoduodenectomy is recommended [17]. In progressive tumors, and unresectable diseases,
cytotoxic chemotherapy can be applied, and surgery can be combined [23].
Long-term use of chemopreventive agents
instead of surgery is not recommended in the primary treatment of FAP. Even so, non-steroidal
anti-inammatory drugs such as sulindac, celecoxib, rofecoxib, and exisulind have been shown
to reduce the number and size of polyps [24]. The
number of colorectal polyps decreased by 28% in
patients with FAP, which are treated with selective cyclooxygenase-2 inhibitor celecoxib twice a
day for 6months [25]. In a randomized, placebocontrolled, double-blind study, genotype (+)
patients were examined, and it was reported that
sulindac did not affect subsequent colorectal polyposis development. Also, in patients with rectal
polyps that were somehow controlled by the
sulindac effect, even so, rectal cancer has developed. Finally, patient compliance is required for
the regular use of these drugs and can cause serious side effects [26]. However, the use of these
drugs can reduce the load of polyps and facilitate
endoscopic management of polyps in patients
with an ileal pouch, high-risk rectum left, or
refusing proctectomy.
19.2.2 Attenuated Familial
Adenomatous Polyposis
Syndrome (AFAP)
The count of adenomatous polyp is 10–99, and it
is inherited autosomal dominant. The number of
polyps is on average 25, and generally, the tendency to locate on the right colon is high. It is
caused by APC mutations inlocalizations such as
far proximal 5′ end of the gene, the far distal 3′
end of the gene, or in certain locations of exon 9
[27]. Complete or partial deletions lead to
AFAP. The age for adenomas to appear is
10–20years later than FAP.The cumulative lifetime risk of developing CRC is 69%. The average
age of occurrence is 55–58 [27]. In the treatment,
there may be no need for any surgical intervention by performing repeated colonoscopic polypectomies. Prophylactic surgery is required either
in the case of the presence of multiple adenomas
that cannot be controlled endoscopically or if the
adenomas are more extensive than 6mm and in
the case of severe dysplasia or suspected cancer.
19.2.3 MUTYH Associated Polyposis
(MAP)
MAP has an autosomal recessive inheritance. It is
caused by biallelic pathogenic germline variants
in the base excision repair MUTYH gene [28].
The most common forms are Y179C and G396D
[29–31]. Patients usually develop between 20 and
99 polyps. The clinic is most often revealed by
the fth or sixth decade [32]. Cancer develops in
40% of MAP patients, and lifetime cumulative
colorectal cancer (CRC) incidence is 70–75%
[33]. Less than 1% of CRC patients are homozygous for MAP. In those who are heterozygous,
the risk of CRC increases to 5–7%. MUTYH
variants have also been identied in patients who
developed CRC without detecting colorectal
polyp [34]. Upper GIS tract polyps may accompany the clinic. For the diagnosis, a test is performed for MUTYH pathogenic germline
mutation. Surveillance takes place with colonoscopy every 5years from the age of 40 or 10years
before the rst diagnosis of the individual with
MAP in the family [35]. Endoscopic polypectomies are performed in the treatment, and prophylactic surgery is recommended in cases where
endoscopy is not sufcient.
19.2.4 Polymerase-Proofreading
Associated Polyposis
It is a newly dened syndrome that causes CRC
and endometrial cancer at a young age. In a
recent study involving 858 early-onset patients, a
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E. Akin et al.
new POLD1 mutation and a known POLE mutation were identied. It appears to be dominantly
hereditary and with high penetration power [8,
36]. There is no consensus regarding its treatment
and surveillance. The frequency of polyps, cancer, and extra-colonic phenotype have not been
revealed yet. However, it seems that close endoscopic surveillance and prophylactic surgery will
be required.
19.3 Hereditary Non-Polyposis
Colorectal Cancer
It is the most common form of hereditary
colorectal cancer and the cause of 3% of colorectal cancers and also referred as Lynch syndrome.
It is an autosomal dominant inheritance predisposing syndrome for cancer with no clear clinical ndings except for solitary adenomas that
may develop cancer. It has been called as
Hereditary Non-polyposis Colorectal Syndrome
since the 1980s because Lynch used this name to
distinguish the disease from other polyposis syndromes. However, with the understanding that
the disease is characterized by colorectal polyps,
only the denition of Lynch Syndrome has
recently been established in the literature. DNA
repair genes (MMR) such as MLH1, MSH1,
MSH6, and PMS1 are mutated [37]. While the
lifetime cumulative CRC risk in MMR (+) individual is 4% for 5years, 10% for 10years, the
risk is 0.04% and 2% for those with MMR (−),
respectively [38]. The average age at which cancer appears is 46, and the risk of developing
extra-colonic cancers is around 5–15% [39].
Patients with a young age presentation can be
explained by the fact that the adenoma-carcinoma sequence, which is 7–10years in sporadic
cancer, is 35months in LS [40]. Synchronous
and metachronous secondary tumors exist in
more than 35% of the patients [41]. Affected
individuals may have 43% endometrium, 19%
stomach, 8% urinary tract, and 9% ovarian cancer [42]. Also, patients should be evaluated for
tumors of the kidney, small intestine, biliary
tract, and brain [43]. The phenotype of osteomas, congenital hypertrophy of the retinal pig-
ment epithelium, dental cysts, and sebaceous
gland tumors has been named Muir–Torre
Syndrome [44].
Clinical and pathological features alone are
not sufcient in diagnosis; family history is
important. The Amsterdam criteria were dened
for the diagnosis in 1991, and the second was
revised and published in 1999, accordingly:
– Diagnosis of colorectal cancer in at least three
relatives, at least one of which is the rst
degree.
– Presence of affected family members in at
least two generations.
– At least one of these cancer patients is diag-
nosed before age 50.
– Endometrium, small intestine, or uroepithelial
cancer accompanying colorectal cancer to
exclude FAP diagnosis [45].
It is important to know that only 60% of families meeting the Amsterdam criteria have an
inherited anomaly in an MMR gene [46].
Demonstration of microsatellite instability (MSI)
supports MMR gene mutation, and immunohistochemical (IHC) assessment shows which gene
the mutation is in [47].
The Bethesda criteria dened in 2004 were
developed to identify the MSI-high status by MSI
or IHC, in individuals who undergo genetic testing for the diagnosis of LS [4, 8, 48]. Provides a
scanning approach with 70% precision,
accordingly:
– Having a diagnosis of CRC before the age of 50.
– Presence of LS-associated synchronous or
metachronous tumor.
– Having a CRC with MSI-high histology
before 60years of age.
– LS-related tumor or CRC diagnosis in one or
more relatives of the rst degree before the
age of 50.
– LS-associated tumor or CRC in two or more
relatives of rst or second degree, at any age.
Surveillance is performed every 1–2 years
with colonoscopy starting at the age of 20–25.
After the age of 40, the evaluation should be done
19 Prophylactic Resections forGenetic Predisposition ofColon andRectum
205
every year with endometrial vacuum biopsies
combined with endo-vaginal USG [49].
Prophylactic surgery is recommended in treatment due to increased risk of CRC, metachronous cancer, and increased adenoma-carcinoma
sequence speed [41]. For this reason, subtotal or
total abdominal colectomy has been advocated
over segmental colectomy to offer the advantage
of decreased risks of metachronous lesions [50].
Risk-reducing surgery is dened as the approach
in which organs with a high risk of developing
cancer are resected. Although surgery for the risk
of the endometrium and ovarian cancer is not recommended for Lynch syndrome in the European
perspective, prophylactic total abdominal hysterectomy and bilateral salpingo-oophorectomy are
recommended for women who are postmenopausal or who do not intend to have children, in
the USA.
19.3.1 Familial Colorectal Cancer
Type X
19.4.1 Peutz–Jeghers Syndrome
It is characterized by hamartomatous intestinal
polyposis and typical mucocutaneous hyperpigmentation. It is autosomal dominant disorder. Its
incidence is 1/80,000–200,000in newborns, lifetime cumulative CRC risk is 39%, and the average age of emergence is 44 [54, 55]. An erroneous
diagnosis of cancer due to epithelial folding can
be made and dened as pseudo-invasion [56].
The localization of polyps is small intestinal
94–98%, colon 25–30%, stomach 21–25%, and
rectum 22–25%, respectively [57]. GIS polyps
exist in 88–100% of patients, and the risk of
malignancy has increased 100–400 times compared to the healthy population [58]. In affected
family members, surveillance is performed biennially with upper and lower GIS endoscopies.
Colonoscopies are initiated at the age of
8–12years.
19.4.2 Juvenile Polyposis Syndrome
It is used to identify patients who meet the
Amsterdam criteria but whose MMR defect cannot be detected [51]. These family members
appear to have a lower incidence of colorectal
cancer relative to individuals belonging to a family in whom an MMR mutation has been detected.
It is presented with, the advanced age of occurrence, rarely metachronous CRC, and a lower
risk of extra-colorectal tumors [51–53].
Prophylactic surgery is not recommended except
for preneoplastic changes unless there are a
germline mutation and phenotypic identication
in individuals at risk.
19.4 Hereditary Hamartomatous
Polyposis Syndromes
Hamartamatous polyposis syndromes are
Cowden syndrome, Bannayan–Ruvalcaba–Riley
syndrome, Peutz–jeghers syndrome, and Juvenile
polyposis syndrome, which are not very common
and differential diagnoses can be made between
them by minor clinical differences.
It is characterized by a large number of polyps in
the colorectal region, stomach, and small intestine [59]. Its incidence in newborns is 1/10,000. It
is autosomal dominant inheritance. The risk of
CRC has increased 34 times in JP, and the cumulative lifetime risk is 30–50% [60]. The average
age of diagnosis is 42. Although at some patients,
it may be seen less frequently, an average of
50–200 polyps are seen, and they may be in different sizes from 1–2 mm to 3 cm. Polyps are
found 98% in the colorectum, 14% in the stomach, 7% in the jejunum and ileum, and 7% in the
duodenum [61]. The risks of developing malignancy are 9–50%. Diagnostic criteria:
– presence of at least 5 polyps located in the
colorectum.
– juvenile polyps in other regions of GIS.
– detection of any number of juvenile polyps in
an individual whose family history is known.
Genetic testing enables diagnosis, evaluation
of family members, as well as differential diagnosis with Cowden syndrome and Bannayan–
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