Original article Peritoneal lavage cytology in patients with oesophagogastric adenocarcinoma J. Nath 1 , K. Moorthy 1 , P. Taniere 2 , M. Hallissey 1 and D. Alderson 1 Departments of 1 Upper Gastrointestinal Surgery and 2 Pathology, University Hospital, Birmingham, UK Correspondence to: Professor D. Alderson, Department of Upper Gastrointestinal Surgery, The Queen Elizabeth Hospital, Edgbaston, Birmingham B15 2TH, UK (e-mail: d.alderson@bham.ac.uk) Background: The aim of the study was to determine the value of performing peritoneal lavage cytology during laparoscopy in the management of oesophagogastric adenocarcinoma. Methods: Laparoscopy combined with peritoneal cytology was performed in patients with potentially resectable oesophagogastric adenocarcinoma. Macroscopic peritoneal findings at laparoscopy and the presence of free peritoneal tumour cells were recorded. All patients were followed to death or the census point. Patients with overt peritoneal disease or positive cytology were offered palliative chemotherapy, subject to performance status. Results: Forty-eight (18·8 per cent) of 255 patients had overt peritoneal metastases at staging laparoscopy. Fifteen (7·2 per cent) of the remaining 207 patients had positive cytology; these patients had a median (95 per cent confidence interval) survival of 13 (3·1 to 22·9) months, versus 9 (7·4 to 10·6) months for those with overt peritoneal metastases (P = 0·517). Of patients receiving chemotherapy, those without overt metastases had a slight survival advantage over patients with metastases (median 15 (10·8 to 19·2) versus 9 (7·4 to 10·7) months; P = 0·045). Conclusion: Positive peritoneal cytology in the absence of overt peritoneal metastases is not uncommon in oesophagogastric adenocarcinoma. It is a marker of poor prognosis even in the absence of overt peritoneal metastases. Paper accepted 31 March 2008 Published online 16 April 2008 in Wiley InterScience (www.bjs.co.uk). DOI: 10.1002/bjs.6107 Introduction Gastric and oesophageal cancers are, respectively, the sixth and seventh most commonly diagnosed solid organ tumours in the UK 1 . Patients with distant metastases identified on cross-sectional imaging have a poor prognosis 2 . They are not candidates for attempted curative surgery. While the sensitivity of multidetector computed tomography (CT) in identifying small-volume disease increases, and new techniques such as positron emission tomography (PET)-CT reveal metastatic disease not disclosed by other tests 3 , the peritoneal cavity remains a common site for metastases that are not apparent with these other modalities. Laparoscopy is widely regarded as the best method for identifying such subradiological peritoneal spread, and is important in preventing unnecessary laparotomy 4 . Peritoneal lavage cytology is a technique that can be used to identify free malignant cells within the peritoneum. It has been applied largely to patients with gastric cancer with tumours in the body or antrum. The presence of free intraperitoneal malignant cells can be explained most easily through shedding of tumour cells from intraperitoneal serosal or metastatic disease. Some studies have identified positive cytology only in the presence of advanced peritoneal disease and concluded that it has no additional value compared with laparoscopy alone 5,6 . Others suggest that positive cytology occurs only in the presence of serosal disease 7–10 . Although intraperitoneal ‘shedding’ probably accounts for the majority of patients with positive cytology, free intraperitoneal malignant cells have also been reported in patients with relatively early (T1 and T2) disease; the hypothesized aetiology for this occurrence is via perforating lymphatic channels 11 . Where curative surgical resection (R0) has been attempted in patients with positive cytology and otherwise potentially curable disease, survival has been poor. Positive Copyright  2008 British Journal of Surgery Society Ltd British Journal of Surgery 2008; 95: 721–726 Published by John Wiley & Sons Ltd