Jejunal flap interposition after total gastrectomy in managing patients with familial adenomatous polyposis: A report on the experience of a single centre.

INTRODUCTION
A surgical technique description video of the laparoscopic approach was published in September 2022.[1]
Familial adenomatous polyposis (FAP) is an autosomal dominant disease, caused by a mutation in the APC gene and causes pre-disposition for hereditary colorectal cancer (CRC).
Its prevalence ranges between 1:20,000 and 1:10,000 in western countries.[2] The natural history of FAP is characterised by the development of adenomatous polyps in the late teens to early twenties. If FAP is left untreated, it will most likely develop into CRC.
Although rare in FAP, gastric cancer (GC) can occur in around 1% of patients. Gastric and duodenal surveillance should be performed once a year as well as other screening examinations for other extracolonic diseases, such as desmoid tumours, namely after proctocolectomy or colectomy, which might be the first, prophylactic surgery.[34]
Duodenal cancer is the most common cause of death in patients who undergo a prophylactic colectomy, making endoscopic duodenal surveillance necessary.

PATIENTS AND METHODS
We analysed the clinical records of patients followed in outpatient consultation for genetic risk of digestive tumours and selected four cases of patients with familial adenomatous polyposis who required risk-reducing total gastrectomy.
The genetic defect associated with each case was identified, as well as the extent of gastric lesions.
Finally, we described the fully laparoscopic technique we used for the interposition of a pedicled isoperistaltic jejunal flap to reconstruct the digestive tract after a total gastrectomy so that duodenal surveillance could be maintained.

RESULTS

Cases submitted to totally laparoscopic approach
Two women with FAP who were followed at our outpatient clinic for risk of hereditary gastrointestinal tumours.

The first patient was a 68-year-old woman with ‘MUTYH-Associated Polyposis (MAP)’ and a c.494A>G mutation at exon 7 and c.1145G>A mutation at exon 13. She was diagnosed with focal gastric cancer, a lesion with high-grade dysplasia of the distal corpus/incisura and two other lesions with high-and low-grade dysplasia in the fundus and antrum. She had previously been submitted to a laparoscopic total colectomy with ileorectal anastomosis in 2009. She also had duodenal and rectum polyps in surveillance and she had been submitted to a breast conservative surgery plus chemoradiotherapy in 2017.

The second patient was a 64-year-old woman with a mutation in nucleotide 1259 of the APC gene (413delA – deletion of an adenine base in the 413th codon), who had multiple foci of low-grade dysplasia and an extensive lesion of the antrum ranging from the incisura to the proximity of the pylorus.

She had been previously submitted to an open total colectomy with ileorectal anastomosis in 1992.
Currently, she was proposed for risk-reduction total gastrectomy because of the extension of her gastric lesions, which she accepted.

Cases submitted to open approach
Our records have data on two cases of open total gastrectomy with interposition of a pedicled jejunal flap between the oesophagus and the duodenum.

3. A 56-year-old male patient with a mutation on exon 15 of the APC gene (3096C > A – S1032X). At age 29, he underwent a prophylactic total colectomy. At age 33, in 1999, he was submitted to an open total gastrectomy with the same reconstruction technique for multiple polyps of the gastric antrum. Multiple sessions of duodenal, jejunal and rectal polypectomies are also recorded.

Currently with good quality of life.

4. A 49-year-old female patient with a c.481C>T mutation on exon 4 of the APC gene.

At age 19, she underwent a prophylactic total colectomy and, at age 23, an open total gastrectomy with the same reconstruction technique, due to more than 100 polyps of the gastric body and fundus. She had multiple polypectomies for rectal polyps, starting at age 20, ileal polyps at age 25, jejunal polyps at age 33 and duodenal polyps at age 40.

Currently with good quality of life.

All four patients had pathological examinations displaying extensive lesions with high-grade dysplasia.
In the first two cases, we intended to do the same of Cases 3 and 4 but using a totally laparoscopic approach.
All the patients went through standard staging with computed tomography scan of the thorax, abdomen and pelvis. They had no signs of advanced disease, and a multidisciplinary team decided to propose surgery to both patients.

Laparoscopic approach – Surgical technique
After induction of anaesthesia, with the patient in the lithotomy position, a pneumoperitoneum pressure of 14 mmHg was set.
Five incisions were used: a 10-mm incision, 3 cm above the umbilicus, another 10-mm incision approximately 3 cm above the first one, along the right mid-clavicular line and third-one on the left mid-clavicular line. A 5-mm incision was done on the subcostal area of the left anterior axillary line. The fifth and last one was a 5-mm sub-xiphoid incision.
The surgery started with abdominal exploration to rule out any sign of disseminated disease.
Then, a total gastrectomy with standard lymphadenectomy was performed.
Afterwards, we proceeded to the reconstructive phase of the surgery, which entailed:

Selection of a jejunal loop to be used in the oesophagojejunal side-to-side anastomosis. This was made about 40–50 cm after the ligament of Treitz, after cutting the loop with a linear endostapler. The loop was then used for the oesophagojejunal anastomosis. The orifices were closed with a hand-sewn polydioxanone 3-0 continuous suture

Connection of the jejunal loop to the duodenum through a side-to-side anastomosis with a linear endostapler and the orifices were closed in the same way as the previous one. That created an isoperistaltic conduit between the oesophagus and the duodenum with just enough extension for a tension-free anastomosis

Section of the jejunal loop immediately distally to the jejunoduodenal anastomosis

Restoration of digestive track continuity with a side-to-side jejunojejunal anastomosis with a linear endostapler, with the orifices being closed in the same way as the previous ones

Closing the spaces between mesenteric folds, to prevent internal hernias

Anastomosis testing with methylene blue

Placement of a drain behind the oesophagojejunal anastomosis, passing near the duodenojejunal anastomosis to exit through the 10-mm incision of the right-side trocar.

Post-operative proceedings

1st post-operative day: only intravenous fluid intake and blood tests

2nd post-operative day: only intravenous fluid intake

3rd–5th post-operative day: step-by-step introduction of clear oral fluids and intravenous fluid intake. No leak tests should be done routinely unless any suspicion sign is detected

6th post-operative day: blood tests, drain removal and solid soft diet

7th post-operative day: dressing verification, dietitian interview, medical recommendations and discharge.

Regarding surgeries performed by laparoscopy approach, the operative time was 4 h and 7 min for the first patient and 4 h and 46 min for the second patient, who needed extensive adhesiolysis due to the previous open abdominal surgery. Blood loss was <150 mL for the first patient <200 mL for the second.
We did not experience any intraoperative or post-operative complications.

Pathological findings
Patient 1: Multiple adenomatous lesions with low- and high-grade dysplasia and pyloric gland polyps (0/26 lymph nodes).
Patient 2: Multiple adenomatous lesions with low- and high-grade dysplasia and fundic gland polyps.
Currently, both patients are healthy.
All procedures were followed in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1964 and later versions. Informed consent was obtained.

DISCUSSION
CRC is the most common malignancy in patients with FAP. When submitted to prophylactic colectomy, duodenal cancer emerges as the most common cause of mortality in this disease. Because of this, duodenal surveillance with upper GI endoscopy is crucial in the follow-up of those patients.[5678]
GC has a high incidence and mortality. It is known that environmental factors have a greater importance in malignancy than genetic factors. However, genetic pre-disposition to gastric neoplasm cannot be ignored, as it is present in several syndromes, such as FAP.[9]
FAP is caused by a mutation in the APC gene and is related to a greater susceptibility to adenomatous polyps. The risk of developing GC is <1%, but duodenal polyps occur in 17%–34% of MAP patients, as was the case in patient number 1.[10]
Gastric adenocarcinoma and proximal polyposis of the stomach is another syndrome that also causes pre-disposition to GC. It is the result of a mutation in the 1B promoter of the APC gene and shows phenotypic overlap with FAP.
In patients with polyps with high-grade dysplasia or GC, gastrectomy is indicated.
There are multiple GI reconstruction procedures in the literature and the Roux-en-Y technique is the most used one. In our own experience, we opted for reconstruction with oesophagoduodenal interposition of an isoperistaltic pedicled jejunal flap to prevent the necessity of duodenal surveillance with endoscopy. This option, described by Longmire, reveals good results in surveillance, dietary imbalance and therapeutic purposes.[11]
Some studies call attention to the issue of quality of life in patients who have undergone a total gastrectomy. Aside from preserving the possibility of endoscopic examination of the duodenum in these patients, whose life expectancy is higher than that of traditional GC patients, since they are frequently diagnosed in earlier stages, owing to the fact that they are routinely screened in specialised care units because of their known higher risk for hereditary tumours, this issue acquires a higher, perhaps even the highest, importance.
The double-tract reconstruction, a technical variant of the Roux-en-Y reconstruction involving an anastomosis between the duodenal stump and the jejunal limb, allows for endoscopic visualisation of the duodenum.[12] The Longmire technique, while similar, has an advantage in the fact that all the food passes through the duodenum, which allows for a better mixture of the pancreatic and biliary juices, as well as a better absorption of nutrients.[13]

CONCLUSION
Jejunal flap interposition after total gastrectomy is a useful surgical technique, with good results in our experience, and all surgical steps can be done entirely through laparoscopy with all the advantages of this approach.

Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest
There are no conflicts of interest.