Peritoneal wash cytology in gastric carcinoma. Prognostic significance and therapeutic consequences.

BACKGROUND AND AIMS

The prognosis of patients with gastric cancer is poor, even following curative resection, and is related primarily to the extent of disease at presentation. In locally advanced gastric tumors, peritoneal lavage cytology (PLC) is a relevant prognostic factor. The Authors present their results of peritoneal washing cytology, evaluating the prognostic value of this technique, and discussing the clinical impact.

PATIENTS AND METHODS

From July 2003 to May 2008, results of PLC in 64 patients with histologically proven primary gastric adenocarcinomas were analyzed. At laparotomy the abdomen was irrigated with 200 ml of normal saline, and ≥50 ml were aspirated and examined by means of cytology and immunocytopathology.

RESULTS

PLC was positive in 7 cases (11%). Overall, 86% of patients with a positive PLC had a pT3/pT4 tumor and 100% with a positive PLC had an N-positive tumor (p < 0.001); 71% of patients with a positive PLC had a grade G3/G4 tumor (p = 0.001). At a median follow-up of 32 months, the cumulative 5-year survival was 28%. The median survival of patients presenting positive PLC (19 months) was significantly lower than that of patients with negative peritoneal cytology (38 months) (p = 0.0001). Multivariate analysis identified cytology as a significant predictor of outcome (p = 0.018).

CONCLUSIONS

Results in the present series demonstrated that patients with a positive peritoneal cytology had advanced disease and poor prognosis, thus indicating that patients with locally advanced gastric cancer should undergo staging laparoscopy and PLC examination in order to select those requiring more aggressive treatment. Future therapeutic strategies should include PLC examination in preoperative staging, in order to select patients for more aggressive treatment.