Importance of Positive Peritoneal Lavage Cytology Findings in the Stage Grouping of Gastric Cancer

Abstract

Although peritoneal lavage cytology is widely performed during surgery for gastric cancer and the results have been reported to be one of the accurate prognostic factors, the cancer stage is determined independent of the results of lavage cytology according to the First English Edition of Japanese Classification of Gastric Carcinoma. In this study we demonstrated the validity of lavage cytology for accurately staging gastric cancer. Between 1988 and 1996, peritoneal lavage cytology was performed in 347 patients with resectable gastric cancer. Among them, cytology was positive in 29 cases (8.4%). The survival rate of the cytology-positive patients in each stage was worse than that of all patients in the same stage. The prognosis of patients with positive cytology findings and serosa-exposed gastric cancer was significantly worse than that of negative cytology findings and serosa-exposed gastric cancer, and similar to that of negative cytology findings and serosa-infiltrating gastric cancer. Our data indicated that positive cytology findings thus indicated a poor prognosis, and the prognostic difference between positive and negative cytology findings was approximately a one-stage difference in the Japanese stage grouping. Based on our findings, the results of peritoneal lavage cytology should thus be included in the factors for staging gastric cancer.

Microscopic Tumor Cell Dissemination in Gastric Cancer

“…22 In a large series of 347 patients, the rate of positive peritoneal lavage cytology was only 8.4%, but there was a clear correlation with poorer survival rates. 23 In the present study, the incidence of patients with tumor cells in the peritoneum was higher than this, but we could not confirm the finding of a lower survival rate. Peritoneal lavage fluid was collected from fewer patients than bone marrow aspirate, and these numbers were probably insufficient to evaluate significant survival differences in the subset of patients with T1 or T2 tumors.…”

Does the Intraoperative Peritoneal Lavage Cytology Add Prognostic Information in Patients With Potentially Curative Gastric Resection?

“…Previous reports have stated that the prognosis in surgically treated patients with gastric carcinoma is significantly affected by the presence of IFCCs at the time of gastrectomy. 6,[8][9][10][12][13][14][15]18,19 The survival rate also appears to be related to the number and the arrangement of IFCCs, that is, clustered, isolated, or clustered-plus-isolated type. 10 None of our patients who had IFCCs survived longer than 17 months after surgical treatment.…”

Laparoscopy alone is superior to peritoneal cytology in staging gastric and esophageal carcinoma

“…According to the current AJCC staging classification of both gastric and esophageal cancer, peritoneal cytology is not considered in the TNM classification; however, in multiple studies positive cytology portends a worse prognosis [1,6,16], and the Japanese Classification of Gastric Cancer now includes cytology as an indicator of stage IV disease [8]. Furthermore, the presence of positive cytology has been offered as an indication for a more thorough lymph node dissection or selection for adjuvant treatment involving intraperitoneal instillation of chemotherapeutics [8,11].…”

“…Malignant cells are present in 7.5-41% of peritoneal lavage specimens in patients with gastric cancer, and studies have shown that the presence of malignant cells may be the only positive finding in 6-29% of patients undergoing staging laparoscopy [2,13]. According to the current American Joint Commission on Cancer (AJCC) staging classification of both gastric and esophageal cancer, peritoneal cytology is not considered in the TNM classification; however, in multiple studies positive cytology portends a worse prognosis [1,6,16], and the Japanese. Classification of Gastric Cancer now includes cytology as indicator of stage IV disease [8].…”