Unfortunately, many patients at the time of diagnosis already have locally advanced gastric tumors, which cannot be removed by surgical procedure, or signs of systemic disease. In Brazil, this number may represent more than 25% of cases. Distal gastric obstruction (gastric outlet obstruction) occurs in about 30% of distal gastric tumors. In these situations, the main non-curative therapeutic modality for the treatment of GC remains the resection of the tumor, but without the need for associated lymphadenectomy.

However, some patients have locally advanced tumors that cannot be resected. The incidence of these varies in the literature from 5 to 30% of GC cases. In these cases, gastrointestinal bypass procedures or the use of endoscopic prostheses may be indicated to improve quality of life, relieve symptoms of gastric obstruction, and thus enable the administration of palliative treatment.

The use of endoscopic prostheses has gained popularity for the palliation of digestive tract obstructions, as it has the advantage of being a less invasive option and without the need for use of the operating room with general anesthesia. However, the multicenter randomized study (Sustent Study) reported worse long-term results with the use of the prosthesis compared to gastrojejunostomy. Factors such as prosthesis migration, tumor growth causing new obstruction, and gastric wall erosion, are long-term complications that impair the observed results. Another aggravating factor refers to the cost and immediate unavailability of prostheses by the public system in our country. Currently, the prosthesis is mainly indicated in patients with low clinical performance by the Eastern Cooperative Oncology Group (ECOG) scale, and with a life expectancy of less than 2 months.

Regarding bypass surgical procedures, the most used is gastrojejunostomy, also called gastroentero anastomosis. Gastrojejunostomy consists of performing anastomosis with a wide extension of the posterior wall of the stomach with the first jejunal loop that reaches the stomach without tension (Figure 1). The anastomosis can be performed manually or mechanically, with the use of surgical staplers.

Despite the technical simplicity of performing gastrojejunostomy, a major inconvenience observed in practice is the difficulty of gastric emptying through the anastomosis after the procedure. Literature data refer that 10 to 26% of patients present this complication, as shown in Figure 1. Such occurrence can lead to an increase in hospitalization time and delay the start of palliative chemotherapy, fundamental to prolong survival.

Another inconvenience of this procedure is the maintenance of the tumor in contact with the food ingested by the patient, since the exposure of the tumor predisposes the occurrence of tumor bleeding. Finally, there is also the risk of obstruction of the gastrojejunostomy by the growth of the tumor that is located near the anastomosis, and can thus invade it. This fear can lead the surgeon to perform the anastomosis in a more proximal portion of the gastric body, which further impairs gastric emptying.

With the aim of overcoming these inconveniences, the performance of a partial partition of the stomach associated with gastrojejunostomy in the proximal gastric chamber has been indicated for non-resectable obstructive distal tumors. The rationale for performing the partition involves creating a gastric chamber of smaller dimensions facilitating emptying by gastrojejunostomy and excluding the tumor in the distal chamber reducing the risk of bleeding and preventing the infiltration of the anastomosis by the tumor.

Technical steps of gastric partition

After identifying the proximal limits of the lesion, a point located 3 to 5 cm proximal to the lesion on the greater curvature is selected to start the partition (Figure 2).

A Faucher tube nº 32 or a large nasogastric tube is passed and maintained along the lesser gastric curvature to maintain communication between the two gastric chambers created by the partition (Figure 3). The partial partition of the stomach is performed using a cutting linear stapler.

Subsequently, the gastrojejunostomy is performed in a position anterior to the colon, isoperistaltic in the posterior wall of the stomach with at least 5 cm of extension, using the first jejunal loop about 30-40 cm from the Treitz angle (Figure 4).

The anastomosis can be performed manually or with the use of a cutting linear stapler. The access route can be conventional or laparoscopic, according to the surgeon’s preference.

It is important to note that in cases of proximal tumors or with involvement of the proximal lesser curvature to the angular incisura the partition should be avoided due to the risk of obstruction of the communication between the gastric chambers.

How to cite this article

Ramos MFKP, Gastric partition for the treatment of non-resectable obstructive distal gastric tumors. Gastropedia 2023 Vol 1. Available at: gastropedia.com.br/sem-categoria/particao-gastrica-para-tratamento-de-tumores-gastricos-distais-obstrutivos-nao-ressecaveis/

Gastric cancer (GC) is the fifth most common cancer in the world. It is estimated that over one million new cases of GC occur annually.

Remnant gastric cancer, or gastric stump cancer, was defined as a tumor that develops in the gastric remnant more than 5 years after previous gastrectomy.

Its reported incidence in the literature varies between 2 to 6% of all patients with GC. It can occur in the remaining stomach either after previous resection for benign or malignant lesion. However, these tumors seem to have different behaviors and etiologies. Due to its rarity and diversity, the characteristics of remnant gastric cancer, prognostic factors and survival, remain uncertain.

Context

Gastric resection for benign disease was commonly performed until the late 1980s and created a large cohort of patients with gastric remnant at risk of developing tumors. The introduction of H2 receptor antagonists and proton pump inhibitors in the 1980s drastically reduced the number of gastric resections due to peptic disease. However, as the disease development period is long, the occurrence of remnant tumors is still part of the current reality due to the past use of gastric resection for peptic ulcer treatment. On the other hand, the improvement in the treatment results of GC has increased the survival of patients undergoing gastric resection, also increasing the population susceptible to the development of new neoplasia in the gastric remnant. Therefore, a change in this benign/malignant ratio related to previous indications of gastric resection is expected in the future.

Long-term endoscopic surveillance is recommended for early detection of lesions in patients who have undergone previous distal gastrectomy. Even with these recommendations, there is a common sense that remnant tumors usually present at a more advanced clinical stage and with a worse prognosis. The longer period of carcinogenic effect after resection, as well as the patients’ perception that they had benign disease, makes them less likely to continue monitoring the gastric remnant for early detection.

Carcinogenesis

The carcinogenesis of GC is a multi-step process that involves the interaction of several genetic, epigenetic and environmental factors. The risk factors commonly associated with the development of GC include chronic infection by H. pylori, low intake of fruits and vegetables, high salt intake, smoking and alcohol consumption.

• After previous gastric resection for malignant disease, this cumulative carcinogenic effect on the gastric mucosa is maintained. For this reason, patients with previous gastrectomy for cancer develop tumors in the remnant in a significantly shorter period than patients with previous benign lesions.
• After gastric resection for benign disease, environmental changes begin to induce chronic damage in a previously normal gastric mucosa of the remnant, initiating a de novo carcinogenic pathway with a longer period for the development of the tumor in the remnant. The reported time required to transform this remaining inflamed mucosa into a neoplastic epithelium is over 20 years.

Another factor contributing to remnant carcinogenesis is the vagotomy performed in the previous procedure, which causes denervation of the gastric mucosa leading to hypochlorhydria. On the other hand, the frequency of H. pylori infection decreases in the remnant mucosa, leading to a protective effect.

Whether these changes actually lead to a higher incidence of GC in the remnant mucosa, or just reflect the normal risk of GC in the general population, is still under discussion. This discrepancy in reports may result from the difference in GC incidence rates in the general population of different countries. Regions with low incidence of GC tend to have a higher proportion of remnant tumors compared to regions with high incidence of GC.

Type of reconstruction and risk of carcinogenesis

The relationship between type of reconstruction and risk of RGC remains uncertain.

• The Billroth I (BI) reconstruction maintains the flow of ingested food from the remaining stomach to the duodenum, but due to pyloric resection the duodeno-gastric bile reflux is increased.
• The Billroth II (BII) reconstruction allows the influx of bile from the afferent jejunal branch to the remaining stomach. This constant flow makes alkaline gastritis more common and severe after BII. This leads to inflammation and regeneration of the mucosa, which may be associated with a higher risk of remnant tumors. Despite some reports in the literature, this association is not yet a consensus.
• On the other hand, the Roux-en-Y reconstruction avoids bile reflux to the remaining stomach, but is rarely performed for benign resections.

Access the Gastropedia surgical video library to see the types of reconstruction

Characteristics and staging

In most cases the remnant tumor is located at the previous anastomosis (Figure 1). Patients usually have a more advanced age which reflects the long period of inflammatory gastritis necessary to induce carcinogenesis in the gastric mucosa. Although the TNM system is applied to all gastric tumors, the staging system for remnant tumors has not been established. For adequate final pathological staging, it is recommended to recover at least 15 lymph nodes to avoid stage migration due to underestimation.

Surgical treatment

Complete total gastrectomy with radical lymphadenectomy is the cornerstone of the treatment of remnant tumors. Adhesion to adjacent organs and displacement of anatomical structures are common difficulties during the procedure, making it longer and more prone to combine repair or resection of other organs. Normally, the surgical procedure is performed by conventional open approach, but recently minimally invasive laparoscopic and robotic approaches are increasing (access gastropedia surgical video library).

It has been suggested that the characteristics of lymph node metastasis in remnant tumors are different due to the interruption of the lymphatic pathway in the first procedure. The type of reconstruction and the previous indication of the first gastrectomy do not seem to influence the incidence of lymph node metastasis, but rather its location. This can lead to a greater involvement of the splenic artery, splenic hilum, lower mediastinum and jejunal mesentery. However, the standard extent of lymphadenectomy is not yet defined. Similar to GC, splenic hilum lymphadenectomy is indicated only if the tumor invades the greater curvature.

The presence of lymph node metastasis in the jejunal mesentery has a poor prognosis. It is known that extended lymphadenectomy in the area can severely affect postoperative quality of life. Therefore, the extent of lymphadenectomy in the mesentery should be determined based on the extent of lymph node involvement, considering a balance between risk and benefit.

References

1. Ramos MFKP, Pereira MA, Dias AR, Dantas ACB, Szor DJ, Ribeiro U Jr, Zilberstein B, Cecconello I. Remnant gastric cancer: An ordinary primary adenocarcinoma or a tumor with its own pattern? World J Gastrointest Surg. 2021 Apr 27;13(4):366-378. doi: 10.4240/wjgs.v13.i4.366.
2. Ramos MFKP, Pereira MCM, Oliveira YS, Pereira MA, Barchi LC, Dias AR, Zilberstein B, Ribeiro Junior U, Cecconello I. Surgical results of remnant gastric cancer treatment. Rev Col Bras Cir. 2020 Nov 30;47:e20202703. doi: 10.1590/0100-6991e-20202703.

How to cite this article

Ramos MFKP, Remnant gastric tumors. Gastropedia 2023 Vol 1. Available at: https://gastropedia.com.br/cirurgia/tumores-do-remanescente-gastrico/

Risk factors commonly associated with the development of gastric cancer (GC) include chronic infection with Helicobacter pylori (H. pylori), low intake of fruits and vegetables, high salt consumption, smoking, and alcohol consumption.

Another known but rarely mentioned risk factor is the presence of Primary Immunodeficiencies (PID), which not only increase the risk of developing GC but also cause its manifestation at earlier ages than in the general population.

PIDs are a set of diseases that encompass more than 300 innate immunity defects, most of which are of unknown cause. PID carriers have an increased risk of recurrent and chronic infections, autoimmune diseases, and neoplasms throughout life.

Following infections, the occurrence of neoplasms is the second most common cause of death in this population. It is estimated that 4 to 25% of PID carriers will develop some neoplasm. Specifically, the risk of developing GC is around 3 to 4 times higher in this population.

Regarding patients with PID, the presence of gastrointestinal disorders is quite frequent, occurring in 5% to 50% of cases. This occurs, in part, because the intestine is the largest lymphoid organ in the human body, containing most of the lymphocytes and producing large amounts of Immunoglobulins. Gastrointestinal manifestations can be related to infection, inflammation, autoimmune diseases, and neoplasms.

Common Variable Immunodeficiency (CVID)

Common Variable Immunodeficiency (CVID) is the most common form of PID, and its prevalence is estimated at 1 in every 25,000 to 50,000 people.

Its pathogenesis has not yet been fully clarified, however mutations of various genes related to the development of B cells into immunoglobulin-producing plasma cells and memory B cells have been described.

Affected individuals commonly present with recurrent bacterial infections of the upper and lower respiratory tract, autoimmune diseases, granulomatous infiltrative disease, and neoplasms. The most common tumors are lymphoma, gastric cancer, and breast cancer.

The diagnosis is based on a significant reduction in serum levels of IgG, IgA and/or IgM, in addition to reduced antibody production after the application of vaccines. Most patients are diagnosed between the ages of 20 and 40, and treatment consists of monthly administration of immunoglobulin.

CVID and Gastric Cancer

The increased risk of GC in patients with CVID varies according to the incidence rate of GC in patients without CVID in the country evaluated. In this sense, a Scandinavian study estimated a 10-fold increased risk, while an Australian study showed a 7.23-fold increased risk.

Although there is no conclusive evidence, the most accepted mechanism for the increased risk of GC in the presence of CVID is due to the reduction in the production of gastric IgA and hydrochloric acid – factors that promote chronic gastritis and facilitate colonization by H. pylori, triggering the carcinogenesis process. This mechanism is supported by the finding that patients with pernicious anemia, who also have achlorhydria and chronic gastritis, have a three times higher risk of developing GC. The decrease in local immune response is also a factor that may play a role in neoplastic development, due to the lower presence of B cells in the gastric mucosa of patients with CVID.

The age of cancer diagnosis in patients with CVID usually occurs at an earlier age, on average 15 years earlier than in the general population.

In relation to the histological diagnosis of the tumor, the Intestinal type of Lauren is usually the most frequent, presenting moderate or poorly differentiated degree. In addition, atrophic pangastritis with little presence of plasma cells, nodular lymphoid aggregates, and apoptotic activity are usually present due to the associated autoimmune gastritis.

Given the evidence of a higher risk of developing GC, it is important that patients with CVID are included in screening programs. Dutch data showed that there is a high incidence of pre-malignant histological and/or endoscopic lesions in patients with CVID, such as atrophic gastritis, intestinal metaplasia, and dysplasia, even in those who are asymptomatic. Up to 88% of CVID patients with no previous gastrointestinal history may present pre-malignant lesions on endoscopy. The rates of progression of these lesions to GC vary from 0–1.8% per year in atrophic gastritis; from 0–10% per year for intestinal metaplasia; and from 0–73% per year when there is already presence of dysplasia.

Intervals between follow-up exams normally employed may not be appropriate for patients with CVID, as the development of GC may occur more quickly. Indeed, there is no standardized screening protocol, and its use should take into account the regional incidence of GC. Patients with CVID can develop high-grade cancer 12 to 14 months after an endoscopy without signs of dysplasia. This justifies the proposal to at least perform EGD in all patients with CVID at the time of diagnosis; repeat it every 24 months in patients with normal histology; every 12 months in patients with atrophic gastritis or intestinal metaplasia; and every 6 months in patients with dysplasia. Routine eradication of H. pylori is also recommended.

Treatment

There are no specific protocols for the treatment of cancer in patients with CVID. Once the diagnosis of GC is made, these patients should undergo standard treatment – the same offered to the immunocompetent population.

Preoperative nutritional support and administration of Immunoglobulin are recommended measures. Patients with CVID can receive the same chemotherapy protocols used in immunocompetent patients. However, short-duration protocols are preferable to long-duration regimes, with special attention to infection control. When possible, the chemotherapy regimen should be adapted according to individual risk factors and tolerance.

Reference

Krein P, Yogolare GG, Pereira MA, Grecco O, Barros MAMT, Dias AR, Marinho AKBB, Zilberstein B, Kokron CM, Ribeiro-Júnior U, Kalil J, Nahas SC, Ramos MFKP. Common variable immunodeficiency: an important but little-known risk factor for gastric cancer. Rev Col Bras Cir. 2021 Dec 15;48:e20213133. English, Portuguese. doi: 10.1590/0100-6991e-20213133. PMID: 34932733.

How to cite this article

Ramos MFKP. Common Variable Immunodeficiency and Gastric Cancer. Gastropedia 2023 vol. 1. Available at: https://gastropedia.com.br/gastroenterology/strongcommon-variable-immunodeficiency-and-gastric-cancer/