Is there a role for treatment-oriented surgery in stage IV gastric cancer? A systematic review

Conversion surgery after successful response to chemotherapy (S-1 + oxaliplatin + nivolumab) in a patient with stage IV gastric cancer with peritoneal metastasis (P1, CY1): a case report

We here present a case report of a patient with Stage IV gastric cancer with peritoneal metastasis (P1, CY1) who underwent conversion surgery after a successful response to chemotherapy (S-1 + oxaliplatin + nivolumab). The patient was a woman in her 60 s. Her chief complaint was epigastric pain. Upper gastrointestinal endoscopy showed Type 4 advanced carcinoma on the lesser curvature of the gastric body. Biopsy showed Group 5 (poorly differentiated adenocarcinoma) and HER2 was negative. Staging laparoscopy revealed seeding in the round ligament of the liver (P1) and adenocarcinoma cells in ascites (CY1). Ten courses of chemotherapy (S-1 + oxaliplatin + nivolumab) were administered, after which contrast-enhanced computed tomography showed that the primary tumor had shrunk and seeding was no longer detectable. Upper gastrointestinal endoscopy revealed scar-like changes. A second staging laparoscopy revealed that ascites cytology was negative and a biopsy of the round ligament of the liver showed no malignant cells (P0, CY0). Conversion surgery comprising laparoscopic total gastrectomy with D2 lymph node dissection and resection of the round ligament of the liver was performed. The postoperative course was uneventful. Histopathological examination of the resected specimen revealed no tumor cells in the gastric mesentery or the round ligament of the liver. The pathological diagnosis was gastric cancer [M, U, L, Less, Ant, Post, type4, T3(SS), N0, M0 (H0, P0, CY0), ypStage IIA]. Adjuvant chemotherapy (S-1) was commenced. The patient is still alive 7 months later with no evidence of recurrence.

Gastric cancer with peritoneal metastases: Efficiency of standard treatment methods

BACKGROUND

Peritoneal metastasis (PM), arising from gastric cancer (GC), is the most common pattern of synchronous and metachronous dissemination and is generally associated with poor prognosis. New therapeutic modalities are being increasingly employed for such patients.

AIM

To develop more advanced methods, it becomes necessary to study the results of existing standard treatment methods in patients with PM in order to perform a comparative analysis of the strategies.

METHODS

A retrospective analysis of the efficiency of standard treatment methods (i.e., palliative chemotherapy, palliative gastrectomy, and the best supportive care) was performed on 200 GC patients with synchronous PM.

RESULTS

The overall survival (OS) rate in 200 GC patients with PM under standard treatment was 5.4 mo. One-year survival occurred in 18.4% of patients. In multivariate analysis, the survival rate was significantly influenced by the following factors: Presence of extraperitoneal metastases, and stage of PM according to both the Japanese Gastric Cancer Association (JGCA) and the peritoneal cancer index (PCI). The median OS and 1-year survival of patients with Р1, P2, and P3 (JGCA) carcinomatosis were 9.8 mo, 6.7 mo, and 4.0 mo, and 47.2%, 18.8%, and 5.1%, respectively. The application of the palliative gastrectomy resulted in an increase in the median OS by up to 17 mo compared to the conservative approach where the value was 8.5 mo (P = 0.05) in patients with Р1 РМ. In patients with Р3, palliative chemotherapy increased the OS by up to 5.6 mo compared to the OS of 3.2 mo (P = 0.0006) for best supportive care. The median OS and 1-year survival of patients with РCI of 1-6, 7-12 and 13+ points were 8.5 mo, 4.2 mo, and 4.1 mo, and 39.8%, 6.7%, and 5.5%, respectively. Palliative gastrectomy increased the median OS to 12.6 mo compared to conservative approach of 8.0 mo (P = 0.03) in patients with РCI of 1-6 points. In patients with РCI 13+ points, only palliative chemotherapy increased the OS to 6.0 mo compared to the OS of 3.4 mo for best supportive care (P = 0.0008).

CONCLUSION

GC patients with PM are characterized by extremely poor prognoses. Long-term survivors were found in the group with PCI of 1-6 points, and there was no survival difference in groups with PCI 7-12 vs PCI 13+ points. Palliative gastrectomy could prove effective in treating patients with early stage PM. The three standard treatment methods are equally effective for moderate stages of PM. In cases with advanced peritoneal carcinomatosis, a significant increase in prognosis was registered only after treatment with palliative chemotherapy.

The Relevance of Serosal Exposure Without Nodal Metastasis in Resectional Gastric Cancer

BACKGROUND

According to 8th AJCC/UICC TNM criteria, stage IIB includes pT1N3M0, pT2N2M0, pT3N1M0, and pT4aN0M0, which includes not only early gastric cancer but also locally advanced cancer. There are currently no data about whether there is any additional impact of serosal exposed cancer without nodal metastasis (pT4aN0) on patients' survival outcomes compared with other subgroups in IIB.

METHODS

Patients who underwent radical gastrectomy for gastric cancer patients were enrolled, including 427 patients in stage IIB; 20 (4.68%), 104 (24.35%), 172 (40.28%), and 131 (30.67%) patients were classified as pT1N3a, pT2N2, pT3N1, and pT4aN0, respectively. Clinicopathological characteristics, recurrence pattern, and survival and recurrence rates were analyzed according to the TNM subgroups.

RESULTS

Cancer-specific and relapse-free survival were significantly worse in serosal exposed cancer than in nonserosal exposed cancer in stage IIB (P = 0.019 and P = 0.015). Recurrence rate was highest in the pT4aN0 subgroup (29.0%) in stage IIB, and peritoneal metastasis was the most common pattern. Survival outcomes of the pT4aN0 subgroup were not significantly different from those of the stage IIIA or pT4aN1 subgroups.

CONCLUSIONS

Patients with serosal exposed cancer without nodal metastasis shows worse cancer specific and disease-free survival with higher incidence of peritoneal metastasis than other subgroups in stage IIB. Further surveillance studies, including staging laparoscopy and active adjuvant therapy, are required in this subgroup of patients.