Sabiston Small Bowel Tumors

Question 1

MC Locations for Small Bowel Tumors

Answer 1

-Adenocarcinoma is the most common malignant neoplasm (30% to 50%)
-Neuroendocrine tumors (NETs) (25% to 30%)

-Adenocarcinomas are more prevalent in the proximal small bowel
-Other malignant lesions are more common in the distal small bowel

Question 2

MC benign Tumor, and MC one to produce Symptoms

Answer 2

-Adenomas are the most common benign tumors

-stromal tumors are the most common benign small bowel lesions that produce symptoms.

Question 3

when a benign tumor is identified at operation, What would You Do ?

Answer 3

-resection is indicated because symptoms are likely to develop over time.

-At operation, a thorough search of the remainder of the small bowel is warranted because multiple tumors are not uncommon

Question 4

Patients with GIST, nearly 20% of patients are found to have

Answer 4

metastatic disease, most commonly in the liver

Question 5

How to Confirm Diagnosis of GIST

Answer 5

biopsy with immunohistochemical staining for
-KIT (95%)
-anoctamin-1 (98%)

stromal tumors express
-CD117
-the KIT proto-oncogene protein that is a transmembrane receptor for the stem cell growth factor
-and 70% to 90% express CD34, the human progenitor cell antigen.

-These tumors infrequently stain positive for
actin (20%–30%), S100 (2%–4%), and desmin (2%–4%)

Question 6

How to measure or predict Mets or Recurrence

Answer 6

-Tumors larger than 5 cm, regardless of mitotic index, have higher rates of metastasis and recurrence

-those with a high mitotic index have a higher risk of metastasis and recurrence regardless of size.

Question 7

Adenomas MC found in which part

Answer 7

20% duodenum
30% jejunum
50% ileum.

Question 8

Which type of Adenoma is considered Premalignant

Answer 8

Both true and villous adenomas are thought to proceed along a similar adenoma-carcinoma sequence as colorectal adenomas

Question 9

in FAP , you perform Screening , when to take Bx

Answer 9

biopsy of all suspicious, villous, or large (>3 cm) adenomas in addition to random duodenal biopsy specimens

Question 10

When to Perform pancreaticoduodenectomy or pancreas-preserving duodenectomy in Fap adenomas

Answer 10

high-grade dysplasia
carcinoma in situ
or a Spigelman stage IV

Question 11

Spigelman

Answer 11

see

Question 12

Recommended surveillance in relation to the Spigelman classification.

Answer 12

see

Question 13

Hamartomas in PJS MC location

Answer 13

are most commonly found in the jejunum and ileum

Question 14

Patients with Small Bowel Hamartomas may also have ?

Answer 14

50% of patients may also have rectal and colonic lesions, and 25% of patients have gastric lesions

Question 15

How To treat Surgically

Answer 15

-Resection > limited to the segment of bowel that is producing complications.

Because of the widespread nature of intestinal involvement, cure is not possible; therefore, extensive resection is not indicated.

Question 16

MC Symptom in PJS is Abd pain Why ?

Answer 16

recurrent colicky abdominal pain, usually the result of intermittent intussusception

Question 17

PJS Extracolonic cancers where ?

Answer 17

occurring in 50% to 90% of patients (small intestine, stomach, pancreas, ovary, lung, uterus, and breast).

Question 18

Hemangiomas of Small Bowel

Answer 18

-submucosal proliferation of blood vessels.
-jejunum MC location
-can be part of Osler-Weber-Rendu disease.
-Turner syndrome > cavernous hemangiomas of the intestine.
-MC Symp intestinal bleeding.
-Angiography and Tc-99m RBC scanning > diagnostic studies.

-If a hemangioma is localized preoperatively, resection of the involved intestinal segment is warranted.
-Intraoperative transillumination and palpation may help to identify a nonlocalized hemangioma.

Question 19

In contrast to benign lesions, malignant neoplasms almost always

Answer 19

-produce symptoms
the most common > pain and weight loss.

-Obstruction usually the result of tumor infiltration and adhesions.

Question 20

NENs Divided into Groups , Mention them

Answer 20

-divided > NETs and neuroendocrine carcinomas

-NETs > benign or malignant type

-subdivided : (grade 1, G1)
(grade 2, G2) and (grade 3, G3) tumors

based on > appearance, mitotic rates, behavior (invasion of other organs, angioinvasion), and Ki-67 proliferative index.

On the other hand, neuroendocrine carcinomas are all G3, poorly differentiated malignant tumors

Question 21

NETs are also categorized based on the embryologic site of origin and secretory product

Answer 21

-foregut (respiratory tract, thymus)
>produce low levels of serotonin (5-hydroxytryptamine) but may secrete 5-hydroxytryptophan or adrenocorticotropic hormone

-midgut (jejunum, ileum and right colon, stomach, proximal duodenum)
>high serotonin production

-hindgut (distal colon, rectum)
> rarely produce serotonin but may produce other hormones, such as somatostatin and peptide YY.

Question 22

In the small intestine, NETs almost always occur within

Answer 22

the last 2 feet of the ileum

Question 23

the most prominent secreted humoral agents by Nets

Answer 23

serotonin and substance P

Question 24

carcinoid syndrome, secondary to serotonin or tachykinin production, is characterized by

Answer 24

episodic attacks of cutaneous flushing
bronchospasm
diarrhea, and vasomotor collapse

is present mostly in those patients with hepatic metastases

Question 25

Primary tumors that secrete directly into the venous system, bypassing the portal system

Answer 25

(e.g., ovary, lung), give rise to carcinoid syndrome without metastasis.

Question 26

MC Location for NETs in GIT ?

Answer 26

small intestine (38%) rectum (34%) Colon (16%) stomach (11%) in Korea, the most common site for NETs is the rectum

Question 27

The malignant potential for NETs (ability to metastasize) is related to

Answer 27

location, size, depth of invasion, and growth pattern smaller than 1 cm> 2% associated with Mets 1 to 2 cm > 50% larger than 2 cm > 80% to 90%

Question 28

gross appearance of NETs

Answer 28

-Small, firm, submucosal nodules , yellow on the cut surface. -subtle as a small whitish plaque seen on the antimesenteric border of the small intestine. -associated with a larger mesenteric mass caused by nodal disease and desmoplastic invasion of the mesentery. -tend to grow very slowly, but after invasion of the serosa, the intense desmoplastic reaction produces mesenteric fibrosis, intestinal kinking, and intermittent obstruction.

Question 29

unusual observation in NETs

Answer 29

-coexistence of a second primary malignant neoplasm of a different histologic type. -synchronous adenocarcinoma (most commonly in the large intestine) > occur in 10% to 20% of patients with NETs. -Multiple endocrine neoplasia type 1 is associated with NETs in approximately 10% of cases

Question 30

Secretory products of neuroendocrine tumors

Answer 30

see

Question 31

Malignant carcinoid syndrome

Answer 31

vasomotor, cardiac, and gastrointestinal manifestations cutaneous flushing (80%) diarrhea (76%) hepatomegaly (71%) cardiac lesions, most commonly right-sided heart valvular disease (41%–70%) and asthma (25%)

Question 32

Cutaneous flushing in the carcinoid syndrome may be of four varieties:

Answer 32

1. diffuse erythematous, > short-lived > face, neck, and upper chest; 2. violaceous, > attacks may be longer > develop a permanent cyanotic flush, with watery eyes and injected conjunctivae 3. prolonged flushes > up to 2 or 3 days > entire body and > profuse lacrimation, hypotension, and facial edema 4. bright-red patchy flushing > gastric NETs.

Question 33

The three most common cardiac lesions are

Answer 33

pulmonary stenosis (90%) tricuspid insufficiency (47%) tricuspid stenosis (42%)

Question 34

Malabsorption and pellagra ?

Answer 34

> Niacin deficiency VitB3 (dementia, dermatitis, and diarrhea) are occasionally present and are thought to be caused by excessive diversion of dietary tryptophan.

Question 35

Diagnose Carcinoid

Answer 35

A combination of serum CgA measurement with 24-hour urine 5-HIAA is an acceptable diagnostic combination with increased sensitivity.

Question 36

CT Diagnose Carcinoid

Answer 36

CT> solid mass with spiculated borders and radiating surrounding strands that is associated with linear strands within the mesenteric fat and kinking of the bowel, a diagnosis of gastrointestinal NET can be made

Question 37

Diagnosis for Carcinoid

Answer 37

-CT Scan -MRI Liver ( For Mets ) -18F-fluorodeoxyglucose PET Scan 18FDG is taken up only in high-grade NETs (e.g., high Ki-67 expression) > most NETs have low Ki-67 expression -18F-L-dihydroxyphenylalanine (18F-DOPA) > improved the sensitivity of PET -Scintigraphic localization > Octreotide is a synthetic analogue of somatostatin, and indium (111In)-labeled pentetreotide specifically binds to somatostatin receptor subtypes 2 and 5. -Somatostatin receptor imaging with gadolinium 68Ga–DOTATATE PET/CT

Question 38

68Ga-DOTATATE PET/CT is a clinically useful imaging technique to

Answer 38

-localize primary tumors in patients with neuroendocrine metastases of unknown origin -to define the existence and extent of metastatic disease.

Question 39

The benefits of 64Cu-DOTATATE imaging

Answer 39

-better true positive lesion detection -longer shelf life and scanning window when compared with 68Ga-DOTATATE, making it an ideal diagnostic too

Question 40

Tx of NETs

Answer 40

-tumors < 1 cm without regional LN Mets > segmental resection - > 1 cm, with multiple tumors, or with regional LN Mets, regardless of the size of the primary tumor, wide excision of bowel and mesentery is required. -Lesions of the terminal ileum > right hemicolectomy. -Small duodenal tumors > excised locally -more extensive lesions may require pancreaticoduodenectomy

Question 41

anesthesia may precipitate a carcinoid crisis , how to Tx

Answer 41

characterized by hypotension, bronchospasm, flushing, and tachyarrhythmias. treated with IV octreotide bolus of 50 to 100 μg > may be continued as an infusion at 50 μg/hr.

Question 42

Mets to liver Tx

Answer 42

-Even with liver metastasectomy > high recurrence rate of 75%. -In these cases, transarterial chemoembolization or radioembolization has been shown to provide liver-directed control of disease. -resection of the primary tumor, with or without mesenteric resection, > improve survival and to slow progression of hepatic metastases in patients with unresectable disease

Question 43

Medical therapy

Answer 43

-Somatostatin analogs (SSAs) are the standard of care -octreotide (Sandostatin) and lanreotide -relieve symptoms and delay cancer progression (antiproliferative effect) -Octreotide LAR is recommended for Grade 1 and 2 NETs and not recommended in grade 3

Question 44

For patients who have disease progression on SSA therapy

Answer 44

-Everolimus, a mammalian target of rapamycin (mTOR) inhibitor, initially developed as immunosuppressant therapy, is approved for the treatment of nonfunctional gastrointestinal NETs with unresectable, locally advanced or metastatic disease

Question 45

somatostatin refractory diarrhea in the setting of carcinoid syndrome

Answer 45

the serotonin synthesis inhibitor, telotristat etiprate

Question 46

Currently, the role of chemotherapy ?

Answer 46

streptozotocin, 5-fluorouracil (5-FU), and cyclophosphamide. -to patients with G2 metastatic disease who are symptomatic, are unresponsive to other therapies, or have high tumor proliferation rates.

Question 47

Resectable adenocarcinomas in the second portion of the duodenum are treated with

Answer 47

pancreaticoduodenectomy regional lymphadenectomy of the periduodenal, peripancreatic, and hepatic lymph nodes as well as involved vascular structures is necessary.

Question 48

For Adenocarcinoma patients with metastatic disease

Answer 48

FOLFOX (oxaliplatin, 5-FU, and leucovorin) FOLFIRI (irinotecan, 5-FU, and leucovorin) as first-line therapy significantly improves the performance status and progression-free survival

Question 49

the main prognostic factor for adenocarcinoma

Answer 49

LN invasion moreover, the number of lymph nodes assessed and the number of positive lymph nodes are of prognostic value (Required > 10 LN)

Question 50

Lymphoma

Answer 50

-in children younger than 10 years, they are the most common intestinal neoplasm. -most commonly found in the ileum -RF > celiac disease and immunodeficient states e.g AIDS -Asymptomatic small bowel lymphomas > chemoresponsive and do not require surgery. -B-cell lymphomas > chemosensitive than T-cell lymphomas and have high remission rates -T-cell lymphomas > more resistant to therapy > progress to symptoms of obstruction or perforation if not resected. -Regardless of cell type, resection is indicated at any onset of symptoms because progression to life-threatening hemorrhage or perforation portends a dismal prognosis

Question 51

GISTs MC Found in ?

Answer 51

more common in the jejunum and ileum

Question 52

GISTs mostly arise from

Answer 52

the muscularis propria

Question 53

The most useful indicators of survival and the risk for metastasis include

Answer 53

the size of the tumor at presentation mitotic index evidence of tumor invasion into the lamina propria.

Question 54

GIST Tx capsule rupture occurs, What to Do

Answer 54

-receive adjuvant therapy regardless of the extent of the tumor before surgery. -It is advisable to perform an en bloc resection, to include adjacent organs, for prevention of tumor capsule rupture. -A laparoscopic approach in patients with large tumors is strongly discouraged.

Question 55

Radiologic criteria for unresectability for GISTS

Answer 55

-infiltration of the celiac trunk, superior mesenteric artery, or portal vein.

Question 56

Small GISTs (<2 cm) found incidentally in surgical specimens, What to Do

Answer 56

do not require further treatment.

Question 57

Algorithm for GIST Tx

Answer 57

see

Question 58

effective treatment for advanced GISTs after failure of either imatinib or sunitinib

Answer 58

Regorafenib > second-generation tyrosine kinase inhibitor that targets c-kit, RET, BRAF, VEGFR, PDGFR, and fibroblast growth factor receptor. -Sorafenib > VEGF, c-kit, PDGFR, and BRAF inhibitor and has been effective in imatinib- and sunitinib-resistant tumors

Question 59

All intraluminal duodenal diverticula require treatment

Answer 59

True, because recurrence of symptoms is certain.

Question 60

For Duodenum diverticula embedded deep within the head of the pancreas

Answer 60

duodenotomy is performed, with invagination of the diverticulum into the lumen, which is then excised, and the wall is closed Alternative methods for duodenal diverticula associated with the ampulla of Vater include an extended sphincteroplasty through the common wall of the ampulla in the diverticulum

Question 61

perforated diverticulum

Answer 61

excised and the duodenum closed with a serosal patch from a jejunal loop. If the surrounding inflammation is severe, > divert the enteric flow> gastrojejunostomy or duodenojejunostomy. Interruption of duodenal continuity proximal to the perforated diverticulum > pyloric closure with suture or a row of staples.

Question 62

if the diverticulum is posterior and perforates into the substance of the pancreas,

Answer 62

operative repair may be difficult and dangerous. Wide drainage with duodenal diversion may be all that is feasible Surgical jejunostomy should also be considered for all patients with acute perforation to ensure nutrition

Question 63

Jejunal and Ileal Diverticula causing malabsorption

Answer 63

secondary to the blind loop syndrome and bacterial overgrowth in the diverticulum can usually be given antibiotics.

Question 64

Obstruction may be caused by enteroliths that form in a jejunal diverticulum , Tx ?

Answer 64

subsequently dislodged and obstruct the distal intestine. treated by enterotomy and removal of the enterolith, or sometimes the enterolith can be milked distally into the cecum. When the enterolith causes obstruction at the level of the diverticulum, bowel resection is necessary.