Clinical Significance of Detection of Carcinoembryonic Antigen in Peritoneal Fluid by Reverse Transcription-Polymerase Chain Reaction in Patients with Gastric Cancer

PURPOSE: Free cancer cells in the peritoneal cavity exfoliated from a tumor are considered to be responsible for peritoneal dissemination in gastric cancer. To detect free cancer cells, a carcinoembryonic antigen (CEA) was introduced to the marker of gastric cancer. The clinical significance of detecting the carcinoembryonic antigen (CEA) mRNA in the peritoneal fluid was evaluated by RT-PCR in patients with gastric cancer. METHODS: In 50 patients with gastric cancer who received a gastrectomy, the peritoneal washing fluids were obtained and the CEA mRNA was detected by RT-PCR and a cytological examination was taken, simultaneously. The results were correlated with the stage and the recurrence of peritoneal seeding. RESULTS: Positive values of CEA mRNA from the peritoneal washing fluids were observed in 24% (12/50) of patients with gastric cancer but of 4% (2/50) showed peritoneal cytology. There were 8 cases of peritoneal seeding in the follow-up and 6 cases of them presented positive CEA mRNA values (50%, 6/12). According to the stage, positive CEA mRNA values from the peritoneal washing fluids were found in 9% (2/21) in stage I, 20% (2/10) in stage II, 33% (5/15) in stage III and 75% (3/4) in stage IV (P=0.030). In the T classification, positive CEA mRNA values were found in 13% (2/15) in T1, 10% (1/10) in T2, 30% (7/23) in T3 and 100% (2/2) in T4 (P=0.031). In the N classification, positive CEA mRNA values were found in 15% (4/26) in N0, 20% (3/15) in N1, 40% (2/5) in N2 and 75% (3/4) in N3 (P=0.055). CONCLUSION: These results suggest that the detection of CEA mRNA by RT-PCR in peritoneal fluid of gastric cancer patients was more sensitive than the peritoneal cytology, and may have a role in selecting patients with a poor prognosis who may benefit from adjuvant therapy.

Postoperative Radiotherapy for Locally Advanced Gastric Cancer / 대한치료방사선과학회지

PURPOSE: Radical gastrectomy is main treatment of gastric cancer. But the result is not satisfactory with surgery alone. Most of pattern of failure remain locoregional recurrence. To improve 5 year survival postoperative chemotherapy with or without radiotherapy has been used. We analyzed patients with stage III and IV stomach cancer who had radical operation and received postoperative radiation therapy combined with or without chemotherapy retrospectively. MATERIAL AND METHOD: From March 1985 to June 1993, 68 patients treated with curative resection and received postoperative adjuvant radiotherapy with 36Gy or more were evaluated. Median age was 60 years(range 28-66 yrs). Patients were followed from 3 to 133 months with median follow up of 48 months. Thirty seven patients had non signet ring adenocarcinoma, 29 signet ring cell, 2 other cell. Patients with stage IIIA, IIIB, IV disease were 19, 25 and 24 respectively. Chemotherapy was given to all patients except two. RESULTS: Five-year overall survival and disease-free survival rate were 36.6% and 33.6%, respectively. Prognostic factor affecting survival were assessed. High ratio of involved/dissected lymph node, signet ring histology showed poor prognosis with statistical significance. Presence of residual tumor after surgery, stageIV, split course of radiation therapy, age, number of involved lymph node, number of lymph node dissection and grade of tumor affected survival without statistical significance. Type of chemotherapy did not affect survival.Recurrence was documented in 34 patients. High recurrence was seen in omentum and peritoneum with 23.5%, and remnant stomach, anastomosis site, A-loop and E-loop had also high recurrence with 13.2%. In field locoregional recurrence was 20.7% and total distant metastases were 39.7%. Total intraabdominal failure was 47.1% and extraabdominal failure was 13.2%. Treatment toxicity was considered to be acceptable. 22.1% of patients had grade 3 and only 1 patient had grade 4 leukopenia. Six patients(8.8%) had weigh loss more than 10%. CONCLUSION: Treatment toxicity was acceptable with combined treatment with chemotherapy and radiotherapy. Locoregional recurrence was relatively low compared to distant failure with addition of irradiation. Peritoneal and omental seeding was high. Five-year surival was increased with combined modality. Radiation may eradicate minimal residual disease and improve survival. To evaluate role of radiation prospective randomized study employing chemotherapy alone and chemotherapy plus radiation is necessary. Futhermore to reduce intraabdominal failure, role of intraabdominal chemotherapy in addition to combined chemotherapy plus radiation has to be explored.