The clinical trial for photodynamic diagnosis mediated 5-ALA for peritoneal metastasis due to advanced gastric cancer.

Abstract

71 Background: In advanced gastric cancer, the diagnosis of peritoneal metastasis is mandatory prior to the decision of therapy, therefore staging laparoscopy (SL) has gained wider clinical acceptance. However, a false-negative rate of 10% using SL has also been reported, which demonstrates the limitation of optical observation for the dissemination of the cancer nest. Photodynamic diagnosis (PDD) by 5-aminolevulinic acid (ALA) has been proposed for peritoneal metastasis in SL and showed higher sensitivity than that of conventional examination. To evaluate effectiveness and safety of ALA-PDD for the diagnosis of the peritoneal disseminations. Methods: Thirteen advanced gastric cancer that had the signs of peritoneal metastasis pointed out by CT scan prior to the treatment were included. Patients were administered 5-ALA (1g/body) orally 4hours prior to the SL. Several lesions regulated to observe bilateral sub- phrenic peritoneum, bilateral flanks and Douglas’s pouch (conventional examination, PDD each). If the nodules suspected for the metastatic lesion were found, they were diagnosed by laparoscopic biopsy. We evaluate the potential of additional detection rate compared to the conventional examination and safety. Results: The patients characters were as below, gender (male: female) = 8:5, Age (median; range) = 69 years old (39-76). The TNM factor were that cT3:4a = 2:11, cN0:1:2:3 = 2:0:7:4, cM0:1 = 10:3(Japanese classification of gastric carcinoma: 3rd English edition).The additional detection rate was 8.3 %( 1/13) and the incidence of adverse effect was 8.3 %( nausea, Grade 1). Conclusions: The ALA-PDD was effective and safe examination for the peritoneal metastasis of gastric cancer. And furthermore, we are now going to conduct the new investigator initiated trial.