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Distal Gastrectomy (Open)

Abstract

Distal gastrectomies are performed in patients with resectable distal gastric cancers. The patient in this situation initially presented to his doctor with symptomatic anemia. Workup included an upper endoscopy which revealed gastritis of the antrum. Appropriately, biopsies were taken which showed adenocarcinoma. Further staging was done with endoscopic ultrasound (EUS) and CT scan of the chest. Because workup was consistent with an early gastric cancer, he was able to undergo surgery up front. In cases of advanced gastric cancer, neoadjuvant therapy is generally offered first. This video shows an experienced gastric surgeon’s technique for performing an open distal gastrectomy with an extended D1 lymph node dissection.

Case Overview

Background

Worldwide gastric cancer is the 4th most common cancer and 2nd most common cause of cancer death. Incidences are highest in Eastern Asia. In the United States, the incidence has been declining but prognosis remains poor as many are still diagnosed in later stages. Risk factors for gastric adenocarcinoma include H. Pylori infection, Epstein Barr virus infection, frequent intake of smoked or salty foods, pernicious anemia, prior gastric surgery, smoking, chronic atrophic gastritis, as well as certain genetic syndromes.

Patients with gastric adenocarcinoma are often asymptomatic until the mass has grown enough to cause symptoms such as obstruction, bleeding, or pain. Patients often complain of epigastric pain or discomfort, nausea, and/or weight loss.1,2

Focused History of Patient

This an 84 year old gentleman with a history of gastritis and a chronic gastroesophageal junction stricture who presented to his primary care physician with symptoms of fatigue and shortness of breath. Bloodwork revealed anemia. At time of presentation he denied any abdominal pain, nausea/vomiting, change in bowel habits, or weight loss.

Physical Exam

Physical exam is often unremarkable in patients with gastric cancer. In advanced cases you may notice cachexia from weight loss. Occasionally depending on the size and location of the tumor and the build of the patient, you may be able to palpate the mass on abdominal exam. Those presenting with gastric outlet obstruction will be distended on abdominal exam. Our patient was well-appearing with a soft abdomen and no masses palpated on exam.

Imaging

Imaging for workup of gastric cancer includes a variety of studies. The initial choice of test for a suspected gastric cancer is usually an upper endoscopy. If ulcers are seen, these should be biopsied as they can harbor cancer as in our patient. Upper endoscopy is usually followed by EUS to determine the depth of invasion, or T stage, of the tumor and to look for involved lymph nodes. Next CT of the chest, abdomen, and pelvis is performed to look for locally advanced and/or metastatic disease. Sometimes PET scan is used, mostly in the setting of following response to neoadjuvant therapy. Patients with locally advanced disease, T3-T4, should undergo a staging laparoscopy with peritoneal washings sent for cytology.

Fig.1a Fig. 1, Upper endoscopy showing mass in pre-pyloric region of stomach.
Natural History

Gastric cancer typically spreads via the lymph nodes or hematogenously and commonly metastasized to the liver, lungs, or peritoneum. It can also spread directly to involve adjacent organs such as the pancreas, colon, etc. The only potential curative therapy for early gastric cancer is surgery. Even with complete resection and negative margins, 5-year survival rate remains low at 35-40% even with neoadjuvant or adjuvant therapy. Patients typically die of complications of metastasis.

Options for Treatment

Treatment for gastric cancer is multi-disciplinary involving surgery, medical oncology, and radiation oncology. Patients with early gastric cancer are generally treated initially with surgery followed by adjuvant therapy pending the pathology. Patients with locally advanced gastric cancer are usually treated up front with neoadjuvant therapy, chemotherapy +/- radiation, followed by surgery.

There are several different approaches to a distal gastrectomy. Traditionally gastrectomies have been done open via an upper laparotomy incision. More recently, more surgeons have been turning to minimally invasive surgery via laparoscopy or robotically. There is much controversy over the appropriate extent of lymph node dissection, D1 versus D2, which will be discussed in the discussion section. There are also several options for reconstruction after the stomach has been removed: a Billroth I gastrojejunostomy, a Billroth II gastrojejunostomy, or a Roux-en-Y reconstruction.

Rationale for Treatment

This patient had early gastric cancer, T2N0, based on staging studies with no evidence of metastatic disease. He, therefore, underwent a distal gastrectomy.

Special Considerations (optional)

Most patients presenting with this tumor would undergo the same treatment. While this patient is 84, he was very healthy and active for his age. Elderly patients with multiple comorbidities without a long life expectancy might not be offered surgery if the risk of surgery is deemed too high.

Patholoy Report

A. DISTAL STOMACH RESECTION:

Gastric adenocarcinoma, tubular type, mismatch repair protein expression instable. (See synoptic report).

B. LYMPH NODE BIOPSY, STATION 8:

There is no evidence of malignancy in four lymph nodes (0/4).

C. LYMPH NODE BIOPSY, STATION 11:

There is no evidence of malignancy in two lymph nodes (0/2).

D. LYMPH NODE BIOPSY, STATION 7:

There is no evidence of malignancy in two lymph nodes (0/2).

E. LYMPH NODE BIOPSY, STATION 3:

There is no evidence of malignancy in one lymph node (0/1).

SYNOPTIC REPORT:

TUMOR STAGE SUMMARY: pT1bN0.

SPECIFIC SITE: Gastric antrum.

TUMOR SIZE (Greatest dimension): 0.3 cm (as measured on slide).

WHO CLASSIFICATION: Tubular adenocarcinoma.

HISTOLOGIC GRADE: G1 (Well differentiated)

EXTENT OF INVASION: pT1b (Tumor invades submucosa).

SMALL VESSEL (BLOOD/LYMPHATIC) INVASION: Absent.

LARGE VESSEL (VENOUS) INVASION: Absent.

PERINEURAL INVASION: Absent.

PROXIMAL GASTRIC MARGIN: Uninvolved by invasive carcinoma.

DISTAL DUODENAL MARGIN: Uninvolved by invasive carcinoma. (clearance= 0.4 cm).

REGIONAL LYMPH NODES: pN0 (No regional lymph node metastasis): 31 lymph nodes examined.

*The lymph node total is inclusive of all specimen parts. The main specimen (specimen A) contained 22 lymph nodes.

HER2 IMMUNOHISTOCHEMISTRY: Her 2 score 0/negative (No reactivity or very faint membranous staining in < 10% of tumor cells).

Additional Studies:

MLH1 and PMS lost.

MSH2 and MSH6 intact.

Additional findings:

Gastric antral mucosa with intestinal metaplasia and high grade dysplasia.

Fundic gland polyp.

Epstein-Barr virus encoded RNA (EBER) is negative.

Discussion

The first partial gastrectomy for gastric cancer was performed by Ludwik Rydygier in 1880. Unfortunately, this patient died 12 hours later of septic shock. Theodor Billroth subsequently performed the first successful partial gastrectomy for gastric cancer in 1881. The patient later died of metastatic disease.3 Despite this early work on gastric cancer, uncertainty existed for some time as to the ideal extent of resection (subtotal/distal gastrectomy or total gastrectomy) for distal gastric cancer. Two randomized controlled trials (RCTs), The French cooperative trial4 and the Italian Gastrointestinal Study trial,5 were published in the late 1900s and settled this question by demonstrating no difference in 5-year survival rate in patients with distal tumors undergoing distal or subtotal gastrectomy compared to those undergoing total gastrectomy.

Subtotal or distal gastrectomy is now the standard of care for distal tumors. However, controversy still exists over the ideal extent of lymphadenectomy, either D1 or D2 (see figures below from Mastery of Surgery1).

Fig.2a Fig. 2a, Lymph node stations including the perigastric, or D1, lymph nodes (stations 1 to 6).
Fig.2b Fig. 2b, Lymph node stations including the regional, or D2 and D3, lymph nodes (stations 7 to 16).
Fig.3a Fig. 3a, Extent of gastric and lymph node resection for lower one-third lesions.
Fig.3b Fig. 3b, Extent of gastric and lymph node resection for middle one-third lesions.

Standard of care in Japan and Korea is to do a D2 or greater lymphadenectomy, but they have not done any RCTs to study the benefits of this over a D1 lymphadenectomy. Retrospective studies from Japan and Korea have shown improved survival with low mortality but they also perform far more gastrectomies than Western countries given the high incidence of gastric cancer. Two RCTs have been performed in Western countries, the Dutch Gastric Cancer Group Trial6 and the British Cooperative trial.7 Both showed no long-term survival advantage of a D2 lymphadenectomy although locoregional recurrence was lower. D2 lymphadenectomies had higher rates of complications compared to a D1, but much of that was due to high rates of concomitant splenectomy and pancreatectomy needed to achieve of D2 resection. More recently, the Italian Gastric Cancer Study Group conducted an RCT of pancreas-preserving D2 surgery vs D1 at high volume centers with surgeons who trained with Japanese master surgeons.8 They significantly reduced the morbidity and mortality seen in the prior RCTs, but did not show a difference in overall 5-year survival. It remains unclear whether there is significant advantage to a D2 lymphadenectomy. At least a D1 lymphadenectomy should be done though and accurate staging requires evaluation of at least 15 lymph nodes. Some studies have shown that ex-vivo dissection of the nodes, or at least dividing them into stations for the pathologists, increases the lymph node yield.9

Patients with advanced, but resectable, gastric cancer have been shown to have improved outcomes with either neoadjuvant or adjuvant chemotherapy. The US Intergroup 0116 trial was an RCT that showed improved survival with adjuvant chemoradiation (5-FU based).10 The MAGIC trial showed a benefit of neoadjuvant and adjuvent chemotherapy (ECF) over just surgery alone.11 More recently, the CRITICS trial showed no benefit of adding radiation to postoperative chemotherapy.12

He is T1bN0 and his cancer was fully resected. He will not need further adjuvant threapy.

Equipment

A fixed abdominal wall retractor system can be very helpful for this operation. Options include a Thompson, Bookwalter, or Omni retractor system. The duodenum and stomach are transected with a stapler device, either an ILA or GIA 100 stapler. Reconstruction can be done with a stapler or hand sewn. We prefer a hand sewn technique.

Disclosures

The authors have no conflicts to disclose.

Statement of Consent

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published on-line.

Citations

  1. Mullen JT. Chapter 87 Gastric Cancer. Mastery of Surgery, 7th Edition. 2017.
  2. Yoon SS, Park DJ. Chapter 18 Gastric Adenocarcinoma. Current Surgical Therapy, 11th Edition. 2014.
  3. Pach R, Orzel-Nowak A, Scully T. Ludwik Rydygier--contributor to modern surgery. Gastric Cancer. 2008;11(4):187.
  4. Gouzi JL, Huguier M, Fagniez PL, et al. Total versus subtotal gastrectomy for adenocarcinoma of the gastric antrum. A French prospective controlled study. Annals of Surgery. 1989;209(2):162-166.
  5. Bozzetti F, Marubini E, Bonfanti G, et al. Subtotal Versus Total Gastrectomy for Gastric Cancer: Five-Year Survival Rates in a Multicenter Randomized Italian Trial. Annals of Surgery. 1999;230(2):170.
  6. Bonenkamp JJ, Hermans J, Sasako M, et al, for the Dutch Gastric Cancer Group. Extended Lymph-Node Dissection for Gastric Cancer. N Engl J Med. 1999; 340:908-914.
  7. Cuschieri A, Weeden S, Fielding J, et al. Patient survival after D 1 and D 2 resections for gastric cancer: long-term results of the MRC randomized surgical trial. British Journal of Cancer. 1999;79(9-10):1522-1530. doi:10.1038/sj.bjc.6690243.
  8. Degiuli, M., Sasako, M. and Ponti, A. Morbidity and mortality in the Italian Gastric Cancer Study Group randomized clinical trial of D1 versus D2 resection for gastric cancer. 2010. Br J Surg, 97: 643–649.
  9. Afaneh C, Levy A, Selby L, et al. Ex Vivo Lymphadenectomy During Gastrectomy for Adenocarcinoma Optimizes Lymph Node Yield. J Gastrointest Surg 2016;20:165-71
  10. JS Macdonald, SR Smalley, J Benedetti , et al. Chemoradiotherapy after surgery compared with surgery alone for adenocarcinoma of the stomach or gastroesophageal junction N Engl J Med 2001;345: 725– 730.
  11. Cunningham D, Allum WH, Stenning SP, et al. Perioperative Chemotherapy versus Surgery Alone for Resectable Gastroesophageal Cancer. N Engl J Med 2006; 355:11-20July
  12. Verheij M, Jansen E, Cats A, et al. A multicenter randomized phase III trial of neo-adjuvant chemotherapy followed by surgery and chemotherapy or by surgery and chemoradiotherapy in resectable gastric cancer: First results from the CRITICS study. Journal of Clinical Oncology 2016 34:15_suppl, 4000-4000

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