Intraoperative lavage for cytological examination in 1,297 patients with gastric carcinoma

A systematic review and meta-analysis of gastric cancer treatment in patients with positive peritoneal cytology

Gastric cancer patients with positive peritoneal cytology as the only marker of metastatic disease have poor prognoses. There is no universal consensus on the most appropriate treatment regimen for this particular patient group. We reviewed and analyzed published data to determine the optimal treatment regimen for patients with peritoneal cytology-positive gastric adenocarcinomas. Six electronic databases were explored [PubMed, Cochrane (Systematic Reviews and Controlled Trials), PROSPERO, DARE, and EMBASE]. The primary outcome was overall survival with secondary outcomes including patterns of recurrence and treatment-related morbidity. Six studies were included for data extraction. There was no significant heterogeneity between studies. The use of S1 monotherapy was associated with a significant survival benefit (HR 0.48; 95% CI 0.32-0.70; p = 0.0002). Intraoperative intraperitoneal chemotherapy (IIPC) with adjuvant chemotherapy showed a trend toward improvement in overall survival (HR 0.70; 9 % CI 0.47-1.04; p = 0.08). A recent randomized controlled trial examining extensive intraperitoneal lavage (EIPL) with IIPC showed a significant improvement in overall survival (5-year overall survival, 43.8% for EIPL-IPC group compared with 4.6% for IPC group). However, these promising results need to be validated in larger prospective randomized trials.

Prognostic value of CEA and CK20 mRNA in the peritoneal lavage fluid of patients undergoing curative surgery for gastric cancer

BACKGROUND

Peritoneal recurrence is the most common type of recurrence in gastric cancer. Although cytological examination of peritoneal lavage fluid has been used to predict peritoneal spread, peritoneal recurrences often occur even in patients with negative cytology. Our previous retrospective study suggested that reverse transcriptase-polymerase chain reaction (RT-PCR) using peritoneal lavage fluid may be useful for predicting peritoneal recurrence in patients with negative cytology. This prospective study was conducted to validate the clinical impact of this RT-PCR method.

METHODS

From July 2009 to June 2012, a total of 118 cT2-4 gastric cancer patients underwent surgery. Since 14 patients were ineligible because they had incurable factors, the remaining 104 eligible patients were evaluated for carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20) messenger RNA (mRNA) using RT-PCR. If either CEA or CK20 mRNA was detected by RT-PCR, the patient was defined as PCR-positive as in our previous study. The association between recurrence-free survival (RFS) and background factors was analyzed using Cox proportional hazards models.

RESULTS

Of 104 patients, 16 (15.4 %) were positive for either CEA or CK20. PCR-positive patients had significantly worse RFS than PCR-negative patients (log-rank p = 0.007). Regarding the pattern of recurrence, 4 of 16 (25 %) PCR-positive patients and 2 of 88 (2 %) PCR-negative patients had peritoneal recurrence (p < 0.001), but there were no significant differences in recurrence at other sites. Cox multivariate analysis indicated only PCR-positivity as a significant predictor of poor RFS (p = 0.029).

CONCLUSION

This prospective study demonstrated that CEA and CK20 PCR results could predict peritoneal recurrence after curative surgery.

Flow Cytometric Quantification of Intraperitoneal Free Tumor Cells is a Useful Biomarker in Gastric Cancer Patients with Peritoneal Metastasis

BACKGROUND

The frequency of intraperitoneal free tumor cells (IPTC) is considered to reflect the severity of peritoneal metastasis (PM). We quantified the relative number of IPTC against leukocytes in peritoneal fluid and evaluated its clinical relevance in gastric cancer (GC) patients, particularly those with PM.

METHODS

Cells recovered from ascites or peritoneal lavage fluid were immunostained with monoclonal antibodies (mAb) to CD45 and CD326 (EpCAM). Using flow cytometry (FACS), CD326(+) and CD45(+) cells were classified as either tumor cells (T) or leukocytes (L) and the T/L ratio (TLR) was calculated in a total of 506 samples obtained from 300 patients with GC and 33 patients with liver cirrhosis (LC).

RESULTS

Median (M) of the TLR of the initial samples obtained from 199 patients with PM(+) GC was 1.32 % (0-1,868.44 %), which was significantly higher than that in patients with PM(-) GC (M = 0 %, 0-0.35 %; n = 101) or LC (M = 0 %, 0-0.031 %; n = 33). In 104 PM(+) patients who received combination chemotherapy including intraperitoneal paclitaxel, the TLR was repeatedly measured in peritoneal fluid obtained from the port. In these patients, the TLR showed a strong correlation with clinical features as well as cytological findings and carcinoembryonic antigen messenger RNA status. Finally, the median survival time of the 11 patients with initial TLR > 10 % was significantly shorter than that of the 52 patients with TLR < 10 % (271 vs. 627 days; p = 0.0002).

CONCLUSION

The TLR excellently reflected tumor burden in the peritoneal cavity, and could be a reliable biomarker to determine the outcome, as well as the effectiveness, of chemotherapy in patients with PM(+) GC.

Prognostic value of genetic detection using CEA and MAGE in peritoneal washes with gastric carcinoma after curative resection: result of a 3-year follow-up

Peritoneal metastasis is the most frequent cause of death in patients with gastric cancer. Reverse transcriptase-polymerase chain reaction (RT-PCR) assay of peritoneal washes has been used to predict peritoneal metastasis of gastric carcinoma. We applied carcinoembryonic antigen (CEA) and melanoma-associated gene (MAGE) RT-PCR for the detection of peritoneal metastasis of gastric carcinoma after curative surgery and evaluated its clinical significance. Peritoneal washes were obtained from 117 patients with gastric carcinoma. MAGE A1-A6 and CEA RT-PCR were performed, and the results were evaluated according to their clinicopathologic characteristics. Three-year follow-up clinical studies were periodically performed, and disease-free survival rates were retrospectively investigated using the medical records. Among 117 peritoneal fluids, 11 cases (9.4%) revealed MAGE expression and 38 cases (32.5%) revealed CEA expression. When focusing on recurrence rates, RT-PCR-positive had much higher recurrence rates than RT-PCR-negative cases (32.5% vs 5.2%, P < 0.01). Univariate analysis revealed that depth of invasion, lymph node metastasis, tumor node metastasis (TNM) stage, Lauren classification, and MAGE and CEA expressions were independent prognostic factors for recurrence. In a multivariate analysis, MAGE expression and TNM stage were significantly and independently related to recurrence in patients who underwent curative resection. MAGE expression was determined to be the most important prognostic factor for recurrence (hazard ratio: 12.487, P < 0.01). It is feasible to identify free cancer cells in peritoneal lavage by using a MAGE A1-A6 and CEA RT-PCR. MAGE RT-PCR results disclosed significant associations with peritoneal recurrence and proved to be the most important factor for the recurrence rate in patients with gastric carcinoma who had undergone radical resection.

The clinical significance of potentially curative resection for gastric cancer following the clearance of free cancer cells in the peritoneal cavity by induction chemotherapy

PURPOSE

The aim of this study was to evaluate the significance of the conversion of the peritoneal cytology from positive to negative following induction chemotherapy in relation to the prognosis after subsequent resection for gastric cancer.

METHODS

This retrospective study was conducted using a prospectively maintained database. A total of 47 patients with free cancer cells in the peritoneal cavity, as evaluated by staging laparoscopy, but no other evidence of distant metastasis, who underwent induction chemotherapy followed by surgery were enrolled in the study. Then, the clinicopathological factors and survival in the study subjects were assessed.

RESULTS

The median survival time and 5-year overall survival rate of the 47 study participants were 20.4 months and 25.0 %, respectively. In 23 of the patients, the peritoneal cytology converted from positive to negative after the induction chemotherapy, and a microscopically margin-negative gastrectomy was performed. The median survival time of 30.4 months and the 5-year survival rate of 34.6 % of these patients was significantly more favorable than the corresponding values of 15.0 months and 17.6 % in the patients who had persistently positive cytology (P = 0.03).

CONCLUSION

Based on our findings, the clearance of free cancer cells in the peritoneal cavity by induction chemotherapy improves the prognosis of patients following subsequent gastrectomy.

Early postoperative intraperitoneal chemotherapy for macroscopically serosa-invading gastric cancer patients

PURPOSE

Peritoneal recurrence is one of the most common patterns of recurrence after gastric cancer surgery and it has a poor prognosis despite all efforts. The aim of this study is to evaluate the prognostic impact of early postoperative intraperitoneal chemotherapy (EPIC) after surgery with curative intent for macroscopically serosa-invading gastric cancer patients.

MATERIALS AND METHODS

The records of 245 patients under the age of 70 were reviewed. These patients were suffering from macroscopically seroa-invading gastric cancer and they underwent curative surgery from 1995 to 2004 at the Kyungpook National University Hospital, Daegu, Korea. The overall survival, gastric cancer-specific survival, complications, and patterns of recurrence were compared between the patients who were treated with EPIC and those who were not.

RESULTS

EPIC was administered to 65 patients, and the remaining 180 patients did not receive this treatment. The 5-year overall and gastric cancer-specific survival rates for the EPIC group were 47.4% and 53.1%, respectively, and those for the non-EPIC group were 26.7% and 29.7%, respectively (p=0.012 for overall survival and p=0.011 for gastric cancer-specific survival). The rates of peritoneal recurrence for the EPIC group and the non-EPIC group were 18.5% and 32.2%, respectively (p=0.038). There were no significant differences in the morbidity or mortality between the two groups. Based on a multivariate analysis of the factors with prognostic significance in univariate analyses, EPIC, pathological lymph node metastasis, differentiation, and the extent of gastric resection were independent prognostic factors.

CONCLUSION

The use of EPIC to treat gastric cancer patients with macroscopic serosal invasions resulted in better survival rate by reducing the risk of peritoneal recurrence.

The critical role of peritoneal cytology in the staging of gastric cancer: an evidence-based review

Positive peritoneal cytology (Cyt+) is an important staging tool for patients with locally advanced gastric cancer. The objective of this review is to evaluate the current literature regarding cytology evaluation in patients with gastric cancer and to provide recommendations on the inclusion of this powerful prognosticator in patients with this disease. A literature search was performed for recent and pertinent studies evaluating peritoneal cytology in patients with gastric adenocarcinoma. Peritoneal cytology as the only evidence for M1 disease is present in up to 10% of patients with locally advanced gastric cancer; survival in the setting of Cyt+ is dismal when gastrectomy is the first line of therapy. Improved survival is associated with response to chemotherapy indicated by conversion to negative cytology, good performance status, and antral tumors. Highly select patients with Cyt+ treated with gastrectomy show improved survival in only some of the available studies. There are high quality studies that support the routine practice of peritoneal cytology evaluation in patients with locally advanced gastric cancer. The role of gastrectomy remains unclear in patients with Cyt+ and clinical trials are needed to define the best treatment option for this select group of patients.

Hyperthermic intraperitoneal chemoperfusion in combined treatment of locally advanced and disseminated gastric cancer: results of a single-centre retrospective study

BACKGROUND

Patients with locally advanced gastric cancer (GC) and/or peritoneal metastases have a poor prognosis despite systemic chemotherapy or palliative surgery. The aim of this retrospective comparative non-randomised study was to evaluate aggressive cytoreduction in combination with hyperthermic intraperitoneal chemoperfusion (HIPEC) as a novel treatment strategy for patients with intraperitoneal disseminated and locally advanced GC.

PATIENTS AND METHODS

Forty-nine GC patients with serosal invasion (n = 19), limited peritoneal metastases (n = 20), or disseminated peritoneal metastases and tense ascites (n = 10) underwent combination therapy with HIPEC. Three matched control groups undergoing standard therapies were retrospectively identified.

RESULTS

Combination therapy for serosa-invasive GC reduced the level of metachronous peritoneal carcinomatosis and increased median survival from 12 months to 22.5 months (p = 0.001). The median and 1-year survival rates for intraperitoneal disseminated GC patients undergoing therapy with the use of HIPEC were 12 months and 68.8% compared with 8 months and 25%, respectively (p = 0.004) for control subgroup patients (palliative chemotherapy). The symptomatic use of HIPEC allows effective elimination of recurrent ascites in GC patients.

CONCLUSION

HIPEC is a well-tolerated and effective method of adjuvant therapy for gastric cancer with high risk of intraperitoneal progression. Cytoreduction followed by HIPEC improves survival in patients with limited peritoneal carcinomatosis of gastric origin.

DJ-1 is involved in the peritoneal metastasis of gastric cancer through activation of the Akt signaling pathway

Peritoneal metastasis is a major cause of death in patients with advanced gastric carcinoma. DJ-1 is now considered to play an important role in the metastasis of various malignancies. However, it remains largely unclear whether DJ-1 is involved in the development of peritoneal metastasis by gastric carcinoma. In the present study, we showed that the expression of DJ-1 was significantly upregulated in gastric cancer specimens with peritoneal metastasis compared to those without peritoneal metastasis. Knockdown of DJ-1 expression significantly inhibited invasion and migration, in vitro and the in vivo peritoneal metastatic abilities of SGC7901 gastric cancer cells. Moreover, knockdown of DJ-1 also diminished the expression of matrix metallopeptidase (MMP)-2 and MMP-9. All of these effects were reversed by restoration of DJ-1 expression. Following investigation of the pathway through which DJ-1 regulates cell invasion and migration, DJ-1 was found to cause phosphorylation of Akt in SGC7901 gastric cancer cells. Inhibition of the Akt pathway in SGC7901 cells mimicked the effects of DJ-1 knockdown on cell migration, invasion, MMP-2 and MMP-9 expression, and abolished the effects of DJ-1 in promoting SGC7901 cell invasion and migration. Taken together, the present study revealed that DJ-1 plays an important role in the development of peritoneal carcinomatosis from gastric carcinoma, at least partially through activation of the Akt pathway and consequent upregulation of MMP-2 and MMP-9 expression. Thus, DJ-1 may be a potential therapeutic target for peritoneal carcinomatosis of gastric carcinoma.

Surgery-induced peritoneal cancer cells in patients who have undergone curative gastrectomy for gastric cancer

BACKGROUND

Some patients who undergo curative gastrectomy with lymph node dissection (LND) for gastric cancer (GC) show subsequent peritoneal metastasis. The source of these metastatic cells remains unclear.

METHODS

Curative gastrectomy with LND was performed in 102 patients with GC. Peritoneal washing was collected before and after gastrectomy. Cytology, reverse transcription-polymerase chain reaction, and cell culture were used to determine the presence of cancer cells. The proliferative potential of tumor cells was evaluated using Ki-67 staining. Tumorigenic capacity was assessed by cell injection into the peritoneal cavity of NOD/ShiJic-scid mice. Peritoneal recurrence-free survival (RFS) and peritoneal recurrence rate (RR) were examined to determine the clinical relevance of detected cancer cells.

RESULTS

Of 102 peritoneal washing samples obtained before gastrectomy, 57 showed no CEA or CK20 mRNA amplification. After gastrectomy, CEA or CK20 mRNA was detected in 35 of these 57 samples, and viable cancer cells were identified in 24. The viable cancer cells in all 24 cases showed Ki-67 positivity, indicating proliferative activity. Cultured viable cancer cells generated peritoneal nodules after spilling over the peritoneal cavity in NOD/ShiJic-scid mice in 4 cases. The peritoneal RFS of patients with CEA or CK20 mRNA amplification after gastrectomy was significantly poorer than that of patients with negative amplification (p < .05). The 24 patients with viable cancer cells in the peritoneal cavity after gastrectomy showed higher peritoneal RR than those without them (p = .033).

CONCLUSIONS

Viable tumorigenic cancer cells spilled into the peritoneal cavity during surgery, indicating that surgery induces peritoneal metastasis.

Test execution variation in peritoneal lavage cytology could be related to poor diagnostic accuracy and stage migration in patients with gastric cancer

PURPOSE

Peritoneal lavage cytology is part of the routine staging workup for patients with advanced gastric cancer. However, no quality assurance study has been conducted to show variations or biases in peritoneal lavage cytology results. The aim of this study was to demonstrate a test execution variation in peritoneal lavage cytology between investigating surgeons.

MATERIALS AND METHODS

A prospective cohort study was designed for determination of the positive rate of peritoneal lavage cytology using a liquid-based preparation method in patients with potentially curable advanced gastric cancer (cT2~4/N0~2/M0). One hundred thirty patients were enrolled and underwent laparotomy, peritoneal lavage cytology, and standard gastrectomy, which were performed by 3 investigating surgeons. Data were analyzed using the chi-square test and a logistic regression model.

RESULTS

The overall positive peritoneal cytology rate was 10.0%. Subgroup positive rates were 5.3% in pT1 cancer, 2.0% in pT2/3 cancer, 11.1% in pT4a cancer, and 71.4% in pT4b cancer. In univariate analysis, positive peritoneal cytology showed significant correlation with pT stage, lymphatic invasion, vascular invasion, ascites, and the investigating surgeon. We found the positive rate to be 2.1% for surgeon A, 10.2% for surgeon B, and 20.6% for surgeon C (P=0.024). Multivariate analysis identified pT stage, ascites, and the investigating surgeon to be significant risk factors for positive peritoneal cytology.

CONCLUSIONS

The peritoneal lavage cytology results were significantly affected by the investigating surgeon, providing strong evidence of test execution variation that could be related to poor diagnostic accuracy and stage migration in patients with advanced gastric cancer.

Diagnostic values of carcinoembryonic antigen in predicting peritoneal recurrence after curative resection of gastric cancer: a meta-analysis

AIM

A meta-analysis was performed to assess the diagnostic values of carcinoembryonic antigen (CEA) in predicting the peritoneal recurrence after curative resection of gastric cancer.

METHODS

The Medline, Embase, Web of Science, Ovid and Cochrane databases, Google Scholar and Vivisimo engines were searched to identify studies reporting on the accuracy of CEA protein or CEA mRNA in predicting the postoperative peritoneal recurrence of gastric cancer. Publication bias was demonstrated by Funnel plots and Egger test. The sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated and summary receiver operating characteristic curves were generated.

RESULTS

Seven and eight studies fulfilled the inclusion criteria for CEA protein and mRNA determination, including 635 and 849 patients, respectively. The pooled sensitivity, specificity and DOR of CEA protein for predicting the peritoneal recurrence were 0.77 (95 % CI 0.69-0.84), 0.89 (95 % CI 0.86-0.92), 29.71 (95 % CI 10.27-85.92), respectively. Similarly, the values for CEA mRNA were 0.82 (95 % CI 0.75-0.88), 0.82 (95 % CI 0.79-0.85) and 22.97 (95 % CI 10.90-48.41). Meanwhile, the sensitivity and DOR of CEA protein or mRNA were higher than those of cytology, while higher specificity was noted in cytology assay.

CONCLUSION

CEA protein and mRNA levels in peritoneal lavage show a high diagnostic accuracy and may help accurately predict the peritoneal recurrence after curative resection of gastric cancer.

Prediction of peritoneal recurrence by the mRNA level of CEA and MMP-7 in peritoneal lavage of gastric cancer patients

A number of tumor markers had been reported to be useful in detecting free cancer cells in the peritoneal cavity and predict peritoneal recurrence in gastric cancer patients. The objective of this study was to compare the clinical impact of different tumor markers in peritoneal lavage fluid using the real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) technique and to screen the most effective ones from them. The peritoneal lavage fluid of 116 patients with gastric cancer was sampled at laparotomy. After RNA extraction and reverse transcription, real-time quantitative polymerase chain reaction (PCR) was performed using the primers and probes for carcinoembryonic antigen (CEA), cytokeratin-20, matrix metalloproteinase-7 (MMP-7), carbohydrate antigen 125, and transforming growth factor-beta-1. Among the 116 patients, 45 (38.8%) were confirmed to have peritoneal recurrence. Any of the PCR-positive results of the five tumor markers could predict peritoneal recurrence in the univariate analysis (P < 0.001). In the multivariate analysis, the PCR results of CEA (P = 0.003) and MMP-7 (P = 0.028) were found to be independent prognostic factors. A real-time quantitative RT-PCR analysis of the CEA and MMP-7 transcripts in peritoneal lavage fluid could effectively predict peritoneal recurrence in advanced gastric cancer patients who underwent a potentially curative resection.

Peritoneal carcinomatosis

Several gastrointestinal and gynecological malignancies have the potential to disseminate and grow in the peritoneal cavity. The occurrence of peritoneal carcinomatosis (PC) has been shown to significantly decrease overall survival in patients with liver and/or extraperitoneal metastases from gastrointestinal cancer. During the last three decades, the understanding of the biology and pathways of dissemination of tumors with intraperitoneal spread, and the understanding of the protective function of the peritoneal barrier against tumoral seeding, has prompted the concept that PC is a loco-regional disease: in absence of other systemic metastases, multimodal approaches combining aggressive cytoreductive surgery, intraperitoneal hyperthermic chemotherapy and systemic chemotherapy have been proposed and are actually considered promising methods to improve loco-regional control of the disease, and ultimately to increase survival. The aim of this review article is to present the evidence on treatment of PC in different tumors, in order to provide patients with a proper surgical and multidisciplinary treatment focused on optimal control of their locoregional disease.

Prognostic information derived from RT-PCR analysis of peritoneal fluid in gastric cancer patients: results from a prospective multicenter clinical trial

OBJECTIVE

The purpose of this study is to define the clinical significance of the molecular analysis of peritoneal lavage fluid in patients with gastric cancer in a multicenter prospective trial.

METHODS

Quantitative RT-PCR with CEA and CK-20 mRNA as target markers was introduced for peritoneal lavage diagnosis in 141 patients with clinically advanced gastric cancer from 9 different institutes. We then evaluated the prognostic factors in patients and also evaluated predictive markers for peritoneal recurrence in 124 patients without peritoneal metastasis at surgery

RESULTS

Out of the 141 cases, 140 patients were successfully analyzed by RT-PCR of peritoneal lavage fluids. According to multivariate analysis, the combined results of RT-PCR (CEA and CK-20) and CK-20 alone in addition to pathological N (pN)-stage were significantly correlated with overall survival. Multivariate analysis showed that the RT-PCR (CEA and CK-20) and CEA alone in addition to pathological T-stage, pN-stage, and histological grade were significantly correlated with peritoneal recurrence after surgery.

CONCLUSION

This is the first multicenter prospective study to show that RT-PCR analysis of peritoneal lavage fluid with the combination of CEA and CK-20 markers was useful for predicting overall survival and peritoneal recurrence in patients with clinically advanced gastric cancer.

Treatment and prevention of peritoneal carcinomatosis from gastric cancer by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: overview and rationale

Peritoneal carcinomatosis (PC) from gastric cancer is a condition with a very bleak prognosis. Most authors consider it to be a terminal disease and recommend palliative therapy only. Multimodal therapeutic approaches to PC have emerged in the last decades, combining cytoreductive surgery (CRS) and peritonectomy procedures with perioperative intraperitoneal chemotherapy (IPEC), including hyperthermic intraperitoneal chemotherapy (HIPEC) and/or early postoperative intraperitoneal chemotherapy (EPIC). We reviewed the pertinent literature concerning the HIPEC modality both for the treatment of established PC and the prevention of peritoneal recurrence after potentially curative gastric cancer (GC) surgery. Basically, the two procedures relate to different aspects of GC and they are not comparable, since the latter has been used as an adjuvant when PC is still not macroscopically evident and the former has been exclusively used in advanced gastric cancer stages with peritoneal dissemination. Data supporting beneficial effects once gastric PC is already manifest is scarce and limited to few centres with specific experience in this field. Conversely, with regards to the peritoneal perfusion for preventing PC in high risk gastric cancer patients, there are phase III trials and meta-analysis which support beneficial effects resulting from the HIPEC procedure. To offer a baseline guide, we summarized the actual status and general outcome obtained by this multimodal technique, in association or not with CRS as treatment of advanced GC.

Peritoneal carcinomatosis in patients with gastric cancer, and the role for surgical resection, cytoreductive surgery, and hyperthermic intraperitoneal chemotherapy

BACKGROUND

The aims of this study were to create a model of peritoneal carcinomatosis in patients with gastric cancer and to evaluates outcomes in patients with gastric cancer treated using surgery and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

A single-institution cohort of patients with gastric cancer was analyzed according to the development of gastric cancer with peritoneal carcinomatosis (GCPC). Variables were evaluated using regression analysis. Kaplan-Meier analysis was used to evaluate outcomes after surgical resection, cytoreductive surgery, and HIPEC.

RESULTS

Age ≤60 years and local tumor stage (T3/T4) were significantly associated with GCPC (odds ratio, 3.95 and 3.94, respectively). Thirty-six-month survival was 57% for patients without peritoneal disease and 39% for patients with GCPC. There was no significant trend of improved survival after surgical management or HIPEC.

CONCLUSIONS

Age ≤60 years and T3/T4 tumor stage are risk factors for GCPC. Intermediate-term survival of patients with GCPC treated with surgical resection or cytoreductive surgery and HIPEC was not improved, though future research should address the possible benefits of aggressive approaches to the treatment of GCRC.

The clinical importance of a transcription reverse-transcription concerted (TRC) diagnosis using peritoneal lavage fluids in gastric cancer with clinical serosal invasion: a prospective, multicenter study

PURPOSE

We have developed a novel molecular method of diagnosis using the technique of transcriptase-reverse transcriptase concerted reaction (TRC) for the detection of cancer micrometastasis. This study prospectively examined the clinical importance of the TRC diagnosis with peritoneal lavage fluids collected from gastric cancer operations at multiple institutes.

METHODS

TRC amplification targeting carcinoembryonic antigen mRNA was applied to detect gastric cancer cells in peritoneal lavage fluids obtained during gastric cancer resections from nine different hospitals. A total of 137 patients with a clinical diagnosis of serosa-invading neoplasms were enrolled to investigate the correlation between the TRC diagnosis and patient prognosis.

RESULTS

Of the 137 patients, 27 (20%) were positive by cytologic examination. In contrast, TRC targeting carcinoembryonic antigen mRNA was positive in 59 of 137 (54%) patients. TRC positivity was associated with a poorer overall survival in all patients and in the 104 patients who underwent a curative operation. TRC positivity also was associated with the peritoneal recurrence-free survival rate in the 104 curative cases. Multivariate analysis showed that TRC positivity and the pathologic N factor were prognostic factors for the overall survival time.

CONCLUSION

Our prospective multicenter study showed that the TRC test using peritoneal lavage fluids could be a potential prognostic factor to predict patient survival and peritoneal recurrence with clinically diagnosed, serosa-invading gastric cancer.

Flow cytometric quantification of intraperitoneal free tumor cells in patients with peritoneal metastasis

BACKGROUND

Peritoneal metastasis (PM) is the most life-threatening type of metastasis in abdominal malignancy. To improve the diagnostic accuracy of cytologic detection (CY) of free tumor cells (FTC) in the peritoneal cavity, we tried to quantify the FTC to leukocyte ratio using flow cytometry in patients with peritoneal metastasis.

METHODS

Cells were recovered from ascites or peritoneal lavages from 106 patients who underwent abdominal surgery and additional 89 samples which were obtained from peritoneal catheter or access port in patients with PM (+) gastric cancer. The cells were immunostained with monoclonal antibodies to CD45 and to CD326 (EpCAM). Using flow cytometry, CD326 (+) and CD45 (+) cells were classified as either tumor cells (T) or leukocytes (L) and the T/L ratio (TLR) was calculated.

RESULTS

In 106 samples obtained by laparotomy, Median (M) of the TLR of PM (+) patients was 1.39% (0-807.87%) which was significantly higher than PM (-) patients (M=0%, 0-2.14%, P < 0.001). In PM (+) patients, 86 CY (+) samples showed higher TLR than 61 CY (-) samples (M=2.81%, 0.02-1868.44% vs. M=0%, 0-3.45%, p<0.0001). In all of the 24 patients who were monitored for TLR before and after intraperitoneal (IP) chemotherapy, the TLR was reduced which was more dramatic than the results of the change in cytology.

CONCLUSIONS

TLR measured with FACS is an excellent reflection of the tumor spread in the peritoneal cavity and could be a reliable diagnostic biomarker to determine the severity of PM as well as effectiveness of IP chemotherapy.

The incremental benefit of two quadrant lavage for peritoneal cytology at staging laparoscopy for oesophagogastric adenocarcinoma

BACKGROUND

Patients with positive peritoneal cytology from oesophagogastric cancer have a poor prognosis. The purpose of this study was to compare lavage cytology from the pelvis alone with the pelvis and subphrenic areas at staging laparoscopy in patients with potentially resectable oesophagogastric adenocarcinoma.

METHODS

Between November 2006 and November 2010, all patients with operable oesophagogastric adenocarcinoma on spiral CT considered fit for surgical resection underwent staging laparoscopy. Subphrenic and pelvic peritoneal lavage for cytology was performed followed by laparoscopic biopsy of any visible peritoneal disease. Patients were divided into groups: macroscopic peritoneal metastases (P+), no macroscopic peritoneal disease with negative cytology (P-C-), no macroscopic peritoneal disease with positive pelvic cytology (P-PC+), no macroscopic peritoneal disease with positive subphrenic cytology (P-SC+), or both (P-PSC+).

RESULTS

A total of 316 staging laparoscopy procedures were performed; 245 patients (78 %) were P-C-, 28 (9 %) were P+, and 43 (14 %) were P-C+, of whom 29 (9 %) were P-PSC+, 10 (3 %) were P-SC+, and 4 (1 %) were P-PC+. Pelvic cytology alone had 76.7 % sensitivity for peritoneal disease, and subphrenic cytology alone had 90.7 % sensitivity.

CONCLUSIONS

Peritoneal lavage for cytology at staging laparoscopy has an incremental benefit for staging oesophagogastric adenocarcinoma in the absence of macroscopic metastatic disease. Subphrenic washings have the highest yield of positive results. Performing isolated pelvic washings for cytology will understage 23.3 % of patients with microscopic peritoneal disease. The routine use of subphrenic in combination with pelvic lavage for cytology at staging laparoscopy in patients with oesophagogastric adenocarcinoma has an incremental benefit in detecting cytology-positive disease over either pelvic or subphrenic cytology alone.

Treatment outcomes of systemic chemotherapy for peritoneal carcinomatosis arising from gastric cancer with no measurable disease: retrospective analysis from a single center

BACKGROUND

Few studies of systemic chemotherapy have focused on gastric cancer with peritoneal carcinomatosis (PC) without measurable lesions. In the present study, we characterized the outcomes of systemic chemotherapy and prognostic factors for gastric cancer with PC, particularly in patients without measurable disease.

METHODS

Clinical data from 211 gastric cancer patients with PC (137 without and 74 with measurable disease) who had received systemic chemotherapy between January 2003 and December 2010 at a single center were reviewed.

RESULTS

The median overall survival (OS) rate of gastric cancer patients with PC with no measurable disease was significantly longer than that of patients with measurable disease (18.0 vs. 11.6 months, p = 0.010). On multivariate analysis, poor performance status [hazard ratio (HR) = 2.15, p < 0.001], the presence of metastatic lymphadenopathy (HR = 2.17, p < 0.001), and high-grade PC (HR = 1.83, p = 0.001) were associated with significantly decreased OS. When patients with low-grade PC were stratified by clinical PC grade, the median OS of those without measurable disease was 19.6 months. The median OS of patients with low-grade PC with no measurable disease was longer than those of patients with high-grade PC without measurable disease, patients with low-grade PC with measurable disease, and patients with high-grade PC with measurable disease (p = 0.001, p = 0.029, and p < 0.001, respectively). Among the patients with low-grade PC, patients who received a gastrectomy had longer survival than patients who did not receive a gastrectomy (p < 0.001).

CONCLUSIONS

In our study, clinically low-grade PC without measurable disease was associated with better outcomes of systemic chemotherapy than the outcomes in the other groups examined. Clinical trials in patients with gastric cancer with PC should be stratified according to PC grade.

Clinical significance of carcinoembryonic antigen in peritoneal lavage from patients with gastric cancer

BACKGROUND

Peritoneal carcinomatosis is the most common pattern of recurrence of gastric cancer, and it is important to identify patients at high risk for recurrence. Although the carcinoembryonic antigen level in peritoneal lavage (pCEA) was reported to be a useful biomarker to predict peritoneal recurrence in a small series, its clinical significance has not been fully validated. We evaluated the clinical significance of pCEA in a large cohort of patients with gastric cancer.

METHODS

We prospectively analyzed the pCEA level in 597 patients with histologically proven gastric cancer who underwent laparotomy.

RESULTS

A significant relationship was demonstrated between the value of pCEA and clinicopathologic features, such as the peritoneal lavage cytology, peritoneal metastasis, the depth of tumor invasion, and the lymph node metastasis. The cutoff value was set at 100 ng/g of protein, and 134 of the 462 patients who underwent curative surgery had positive pCEA findings. The overall and the intraperitoneal-recurrence-related survival of patients positive for pCEA were significantly poorer than those of pCEA-negative patients. When we analyzed the patients with pathologic stage I through III gastric cancers separately, the pCEA-positive patients had poorer prognoses than the pCEA-negative patients who had stage III gastric cancer. In a univariate analysis, the tumor size, depth of tumor invasion, lymph node metastasis, histologic type, serum CEA (sCEA), and pCEA were found to affect the patients' outcomes, although a multivariate analysis found only the extent of lymph node metastasis to be an independent prognostic factor.

CONCLUSION

The pCEA level is a useful biomarker to predict gastric cancer-related death. Moreover, the pCEA level may be useful to identify a cohort of patients with gastric cancer who need more intensive adjuvant chemotherapy to improve their prognoses.

Levels of CEA and Ca 19 - 9 in the sera and peritoneal cavity in patients with gastric and pancreatic cancers

PURPOSE

Tumor markers are substances found in blood and other biological fluids if tumor is present in the body. They can be produced by tumor itself or can be results of cancer - body relation. They may be used in the follow-up of cancer patients to identify tumor recurrence. Pre-treatment levels have prognostic tool and could signalize persistence of minimal residual disease despite radical surgery.

METHODS

We operated on 52 patients with upper GI malignancy (32 with gastric cancer and 20 with pancreatic cancer). Blood samples were taken before surgery and peritoneal samples immediately after laparotomy before any manipulation with tumor. All samples were examined by standard biochemical technique and the level was compared with a stage of the disease.

RESULTS

Patients suffering from gastric carcinoma of stage I and II had higher level of both markers in sera then in the peritoneal cavity, however most of them were within physiological range. Patients in stage III and IV had average marker levels in the peritoneal cavity higher than in sera. Number of positive findings was increasing according to the stage of the disease. The peritoneal levels of both markers varied extremely in higher stages. In patients suffering from pancreatic carcinoma the CEA levels both in sera and peritoneal cavity were parallel but peritoneal levels were slightly higher in stages III and IV. Ca 19 - 9 was more sensitive for pancreatic cancer. The percentage of positive findings was higher in sera but the level of Ca 19 - 9 was higher in the peritoneal cavity. The number of positive findings again correlated with the stage of the disease.

CONCLUSIONS

Levels of tumor markers in sera could signalize inoperability of tumor (Ca 19 - 9 in cases of pancreatic carcinoma); peritoneal levels could predict R1 resection especially in gastric cancer patients and risk of early peritoneal recurrence of the disease. Difference between the levels in the peritoneum and sera may signalize the route of dissemination (hematogenous and intraperitoneal).

Laparoscopy and peritoneal cytology: important prognostic tools to guide treatment selection in gastric adenocarcinoma

BACKGROUND

Previous studies have suggested that patients with occult peritoneal metastases not seen on preoperative imaging have poor prognosis. In this study, we aim to evaluate the utility and impact of staging laparoscopy and peritoneal cytology in patients with gastric adenocarcinoma.

METHODS

A retrospective analysis of patients with gastric adenocarcinoma managed at two major metropolitan hospitals in Melbourne, Australia, between January 1999 and July 2010 was undertaken. The main outcome measures were the number of patients in whom laparoscopy and/or peritoneal cytology changed treatment intent, and the overall survival of patients with occult metastases detected by laparoscopy/cytology.

RESULTS

Staging laparoscopy as an independent procedure was performed in 74.3% (148/199) of patients who had neither unequivocal metastases (M1) on preoperative imaging nor early T1 disease on endoscopic ultrasound. Laparoscopy/cytology detected occult metastases in 38 (25.6%) patients (27 macroscopic M1 and 11 microscopic M1 with positive peritoneal cytology only), leading to change in the treatment intent in 37 cases. The median overall survivals of patients with metastatic disease detected at staging laparoscopy (8.3 months, 95% confidence interval (CI) 5.4-16.5) or on peritoneal cytology (4.9 months, 95% CI 4.2-48) were as poor as those with M1 disease seen on preoperative imaging (6.7 months, 95% CI 4.2-8.9), P = 0.97.

CONCLUSIONS

Laparoscopy and peritoneal cytology add incremental value to modern imaging in the staging of gastric adenocarcinomas by detecting occult metastatic disease. Their utility needs to be optimized to allow better treatment selection for gastric cancer patients.

Lack of prognostic significance of conventional peritoneal cytology in colorectal and gastric cancers: results of EVOCAPE 2 multicentre prospective study

AIM

In digestive cancers, the prognostic significance of intraperitoneal free cancer cells remains unclear (IPCC). The main objective of this study was to assess the prognostic significance of IPCC in colorectal and gastric adenocarcinoma. The secondary objectives were to evaluate the predictive significance of IPCC for the development of peritoneal carcinomatosis (PC) and to evaluate the prevalence of synchronous PC and IPCC.

METHODS

This was a prospective multicentre study. All patients undergoing surgery for a digestive tract cancer had peritoneal cytology taken. Patients with gastric and colorectal cancer with no residual tumour after surgery and no evidence of PC were followed-up for 2 years. The primary end point was overall survival.

RESULTS

Between 2002 and 2007, 1364 patients were enrolled and 956 were followed-up over 2 years. Prevalence of IPCC was 5.7% in colon cancer, 0.6% in rectal cancer and 19.5% in gastric cancer. The overall 2-year survival rate for patients with IPCC was 34.7% versus 86.8% for patients with negative cytology (p<0.0001). By multivariate analysis, IPCC was not an independent prognostic factor. No relationship between cytology and recurrence was found.

CONCLUSION

The presence of IPCC was not an independent prognostic and didn't add any additional prognostic information to the usual prognostic factors related to the tumour (pTNM and differentiation). Moreover the presence of IPCC detected with this method didn't appear to predict development of PC. Peritoneal cytology using conventional staining doesn't seem to be a useful tool for the staging of colorectal and gastric cancers.

Phase I/II study of intraperitoneal docetaxel plus S-1 for the gastric cancer patients with peritoneal carcinomatosis

Purpose

We designed a phase I/II trial of intraperitoneal (IP) docetaxel plus S-1 to determine the maximum tolerated dose (MTD) and recommended dose (RD) and to evaluate its efficacy and safety in gastric cancer patients with peritoneal carcinomatosis (PC).

Methods

Patients with PC confirmed by laparoscopy or laparotomy received IP docetaxel on days 1 and 15 and S-1 (80 mg/m²) on days 1–14 every 4 weeks.

Results

In the phase I part (n = 12), each cohort received escalating doses of docetaxel (35–50 mg/m²); the MTD was determined to be 50 mg/m² and the RD was determined to be 45 mg/m². Dose-limiting toxicities included grade 3 febrile neutropenia and grade 3 diarrhea. In the phase II part (n = 27), the median number of courses was 4 (range 2–11). The 1-year overall survival (OS) rate was 70 % (95 % confidence interval 53–87 %). The overall response rate was 22 % and peritoneal cytology turned negative in 18 of 22 (81 %) patients. The most frequent grade 3/4 toxicities included anorexia (19 %), neutropenia (7 %), and leukopenia (7 %).

Conclusion

IP docetaxel plus S-1 is active and safety in gastric cancer patients with PC.

Ascites and malnutrition are predictive factors for incomplete cytoreductive surgery for peritoneal carcinomatosis from gastric cancer

BACKGROUND

Prognosis in peritoneal carcinomatosis from gastric cancer has improved with cytoreductive surgery (CS) and hyperthermic intraperitoneal chemotherapy. The aim of this study was to identify predictive factors for incomplete CS.

METHODS

Forty-five patients undergoing laparotomy for gastric cancer with peritoneal carcinomatosis were prospectively included from January 2000 to December 2010. In case of optimal CS, patients (n = 14) received hyperthermic intraperitoneal chemotherapy. Otherwise, the laparotomy was closed or a palliative procedure was performed if necessary. All preoperative data were compared between the 2 groups.

RESULTS

Ascites (hazard ratio, .09; 95% confidence interval, .010-.48; P = .0103) and nutritional status evaluated by the prognostic nutrition index (hazard ratio, .11; 95% confidence interval, .0019-.54; P = .027) were independent predictive factors for incomplete CS.

CONCLUSIONS

The selection of patients for CS plus hyperthermic intraperitoneal chemotherapy should include the assessment of nutritional status and the detection of an ascites.

The prognosis of gastric cancer patients with marginally elevated carcinoembryonic antigen (CEA) values after D2 radical gastrectomy

AIM

To investigate the clinical significance of the postoperative serum carcinoembryonic antigen (CEA) levels in gastric cancer patients who underwent D2 radical gastrectomy and to identify the prognostic factors for patients with marginally elevated postoperative CEA levels.

METHODS

We performed a retrospective study of 480 patients who were histologically diagnosed with gastric cancer and who underwent D2 radical surgery at the Sun Yat-sen University Cancer Center between January 2004 and December 2009. The follow-up lasted until June 2011. Chi-squared tests and Kaplan-Meier methods were employed to compare the adverse events and prognoses.

RESULTS

In this group of gastric cancer patients, the postoperative serum CEA level (P = 0.002) was an independent prognostic factor; the same was true for the histological T and N staging (P < 0.001 and P = 0.045, respectively). In the group of marginally elevated postoperative CEA level gastric cancer patients, univariate analysis demonstrated that tumor position (P = 0.042); histological grade (P = 0.002); and Boarrmann type (P = 0.003) were significant prognostic factors. Multivariate analysis showed that the tumor position (P = 0.003) and histological grade (P = 0.007) were independent prognostic factors for these patients.

CONCLUSION

Our study showed that patients with normal postoperative CEA levels have a better prognosis. Furthermore, for marginally elevated postoperative CEA level gastric cancer patients, the tumor position and histological grade were two important factors for predicting the prognosis and the need for aggressive therapy.

Risk stratification for serosal invasion using preoperative predictors in patients with advanced gastric cancer

Purpose

Although serosal invasion is a critical predisposing factor for peritoneal dissemination in advanced gastric cancer, the accuracy of preoperative assessment using routine imaging studies is unsatisfactory. This study was conducted to identify high-risk group for serosal invasion using preoperative factors in patients with advanced gastric cancer.

Materials and Methods

We retrospectively analyzed clinicopathological features of 3,529 advanced gastric cancer patients with Borrmann type I/II/III who underwent gastrectomy at Korea Cancer Center Hospital between 1991 and 2005. We stratified patients into low- (≤40%), intermediate- (40~70%), and high-risk (>70%) groups, according to the probability of serosal invasion.

Results

Borrmann type, size, longitudinal and circumferential location, and histology of tumors were independent risk factors for serosal invasion. Most tumors of whole stomach location or encircling type had serosal invasion, so they belonged to high-risk group. Patients were subdivided into 12 subgroups in combination of Borrmann type, size, and histology. A subgroup with Borrmann type II, large size (≥7 cm), and undifferentiated histology and 2 subgroups with Borrmann type III, large size, and regardless of histology belonged to high-risk group and corresponded to 25% of eligible patients.

Conclusions

This study have documented high-risk group for serosal invasion using preoperative predictors. And risk stratification for serosal invasion through the combination with imaging studies may collaboratively improve the accuracy of preoperative assessment, reduce the number of eligible patients for further staging laparoscopy, and optimize therapeutic strategy for each individual patient prior to surgery.

The progression potential of peritoneal dissemination nodules from gastrointestinal tumors

It is necessary to examine the characteristics of the dissemination nodules to establish a therapeutic strategy for peritoneal dissemination from digestive malignancy. Ki-67 expression as a proliferation marker in peritoneal dissemination nodules was investigated. The subjects were 15 patients with gastrointestinal cancers who underwent resection of the primary tumor and disseminated nodules. The expression of Ki-67 in both primary tumor and peritoneal dissemination nodule from each patient was evaluated by immunohistochemistry. Ki-67 labeling index in the original tumor was higher than that in the disseminated nodule in 13 of 15 patients (P < 0.0001). The mean value of Ki-67 labeling index was 42.2% in the 15 original tumors and 18.7% in the 15 disseminated nodules. Proliferative activity in the disseminated nodules was lower than that in the primary tumors. Further examination about characteristics of cancer dissemination is needed to treat patients with peritoneal metastasis.

Role of vascular endothelial growth factor (VEGF) and VEGF-R genotyping in guiding the metastatic process in pT4a resected gastric cancer patients

In radically resected gastric cancer the possibility to predict the site of relapse could be clinically relevant for the selection of post-surgical management. We previously showed that specific tumour integrins genotypes are independently associated with either peritoneal or hematogenous metastases (ITGA and ITGV). Recently VEGF and VEGF-R polymorphisms have been demonstrated to potentially affect tumour angiogenesis and the metastatic process in gastric cancer. We then investigated the role of VEGFs and VEGF-R genotyping in determining either peritoneal carcinosis or hematogenous metastases in radically resected gastric cancer patients. Tumour genotyping for integrins (ITGA and ITGV) was also performed according to our previous findings. Genotyping for VEGF-A, VEGF-C, VEGFR-1,2,3 and ITGA and ITGV was carried out on pT4a radically resected gastric tumours recurring with either peritoneal-only carcinosis or hematogenous metastases. 101 patients fulfilled the inclusion criteria: 57 with peritoneal carcinomatosis only and 44 with hematogenous spread only. At multivariate analysis, intestinal histology and the AC genotype of rs699947 (VEGFA) showed to independently correlate with hematogenous metastases (p = 0.0008 and 0.008 respectively), whereas diffuse histology and the AA genotype of rs2269772 (ITGA) independently correlated with peritoneal-only diffusion (p = <0.0001 and 0.03 respectively). Our results seem to indicate that combining information from genotyping of rs699947 (VEGFA, AC), rs2269772 (ITGA, AA) and tumour histology could allow clinicians to individuate gastric cancer at high risk for recurrence either with peritoneal or hematogenous metastases. The selection tool deriving from this analysis may allow an optimal use of the available treatment strategies in these patients.

βig-h3 supports gastric cancer cell adhesion, migration and proliferation in peritoneal carcinomatosis

βig-h3 is an extracellular matrix protein and its expression is highly induced by transforming growth factor (TGF-β). It has also been suggested to play an important role in the growth and invasion of colon and pancreatic cancers. In the present study, we demonstrated that βig-h3 is expressed in mesothelial cells, especially in patients with advanced gastric cancer. The positive rate of βig-h3 was significantly higher in cases with a more invasive and advanced serous-type, with visible peritoneal metastasis, and in peritoneal lavage cytological examination (PLC) (+) and peritoneal lavage fluid CEA mRNA(+) subgroups (p<0.05). Our study also showed that the expression of βig-h3 gradually increased with increasing TGF-β1 concentrations in vitro in a time-dependant manner. In addition, βig-h3 also induced human gastric carcinoma cell line (SGC-7901) cell adhesion in a dose-dependent manner and significantly increased cell migration and proliferation. The results suggest that βig-h3 expression in peritoneal mesothelial cells in gastric cancer patients is a marker of the biological behavior of gastric cancer and plays an important role in the process of peritoneal carcinomatosis.

Correlation of βig-h3 expression in peritoneal mesothelial cells with pathological parameters and peritoneal metastasis in gastric cancer

AIM: To determine the expression of βig-h3 in peritoneal mesothelial cells in gastric cancer and to explore its relation to pathological parameters and peritoneal metastasis.

METHODS: Peritoneal tissue and peritoneal washing fluid samples were collected during operation from 75 patients with gastric cancer and 14 patients with benign gastric lesions. The expression of βig-h3 in peritoneal mesothelial cells was measured immunohistochemically. The mRNA levels of CEA in ascites and peritoneal washing fluid were measured by RT-PCR. Peritoneal lavage cytological (PLC) examination and pathological examination were also performed.

RESULTS: βig-h3 was positively expressed in the peritoneal tissue in 29 patients with gastric cancer and 1 with benign gastric lesions, and the positive rate was significantly different between the two groups (P = 0.030). In the gastric cancer group, 13 patients had evident peritoneal metastasis, 20 were positive for PLC, and 32 were positive for CEA mRNA. The positive rate of βig-h3 expression was significantly positively correlated with deep invasion (P = 0.016), serious serous type (P = 0.037), peritoneal metastasis (P = 0.002), PLC (+) (P = 0.005), and CEA mRNA (+) (P = 0.027).

CONCLUSION: βig-h3 expression in peritoneal mesothelial cells in gastric cancer patients is closely related with peritoneal metastasis, representing a marker of biological behavior of gastric cancer.

Significance of palliative gastrectomy for late-stage gastric cancer patients

PURPOSE

To investigate the significance of palliative gastrectomy for different types of metastatic gastric cancer patients displaying peritoneal dissemination, hepatic metastasis, distant lymph node metastasis occurring locally during late-stage disease, and multi-organ metastases.

METHODS

We performed a retrospective study of 862 patients who were histologically diagnosed as late-stage gastric cancer who could not undergo radical surgery at the Sun Yat-sen University Cancer Center between January 1993 and December 2008. The follow-up lasted until December 2010. Chi-square tests and Kaplan-Meier methods were employed to compare the adverse events and prognoses.

RESULTS

In the peritoneal dissemination and multi-organ metastases groups, palliative gastrectomy has no survival benefit (P = 0.705, 0.331, respectively). In the patients with distant lymph-node metastases, liver metastasis and locally late-stage gastric cancer patients, palliative gastrectomy was a prognostic factor (P < 0.001, P < 0.001, P = 0.010, respectively). Multivariable analysis demonstrated that palliative gastrectomy was an independent prognostic factor for distant lymph-node metastases, liver metastasis, and local late-stage gastric cancer patients. Palliative gastrectomy combined with hepatectomy proved to be an independent prognostic factor to improve the overall survival of patients with liver metastases who underwent palliative gastrectomy (P = 0.008).

CONCLUSION

For late-stage gastric cancer patients, palliative gastrectomy should be considered for locally late-stage, distant lymph node metastasis, and resectable liver metastasis patients. Especially among patients with liver metastasis, transfer medicine is essential for potentially curable patients to obtain access to radical surgery to improve the prognosis.

Clinicopathological analysis and prognostic significance of peritoneal cytology in Chinese patients with advanced gastric cancer

BACKGROUND

The influence of peritoneal cytology on survival of patients with gastric cancer has not been consistent. This study was to identify risk factors for positive peritoneal cytology and to evaluate the predictive value of positive cytology among Chinese patients with advanced gastric cancer.

METHODS

The study included 139 patients with gastric cancer macroscopically invading the serosa, who underwent gastrectomy and intra-operative peritoneal cytological examination. In these patients, the relationship between cytological positivity and various clinicopathological features was analysed, and survival analysis was performed to identify independent prognostic factors of significance.

RESULTS

Thirty-eight (27.3%) of 139 patients had positive peritoneal cytology. Although tumour size, lymphovascular invasion, depth of tumour invasion, lymph node metastasis and peritoneal metastasis were correlated with positive cytology, multivariate analysis revealed the depth of tumour invasion and peritoneal metastasis as the independent features affecting the cytology. Patients with a positive cytology result were confirmed to have a greater risk for recurrence in the pattern of peritoneal carcinomatosis and a significant inferior prognosis. Multivariate analysis indicated that positive peritoneal cytology was an independent prognostic factor among the curatively resected patients with advanced gastric cancer and was the prognostic factor most predictive of death for these patients (risk ratio = 2.74).

CONCLUSIONS

Positive peritoneal cytology correlated with advanced features of gastric cancer. It is an independent poor prognostic factor, and it may serve as a guide for adjuvant therapeutic options to improve the survival of gastric cancer.

Laparoscopic resection for gastric carcinoma: Western experience

There has been much speculation regarding differences in outcome for patients who have gastric cancer in the Eastern versus Western world. Among other factors, these differences have contributed to a unique cohort of patients and experience in the Western staging/evaluation of gastric cancer and in the application of minimally invasive approaches for treatment. This review summarizes the current state of laparoscopic approaches for the staging and treatment of gastric adenocarcinoma for patients presenting in Western countries, with their associated unique presentation, comorbidities, and outcomes.

A proposal of a practical and optimal prophylactic strategy for peritoneal recurrence

Peritoneal metastasis, which often arises in patients with advanced gastric cancer, is well known as a miserable and ill-fated disease. Once peritoneal metastasis is formed, it is extremely difficult to defeat. We advocated EIPL (extensive intraoperative peritoneal lavage) as a useful and practical adjuvant surgical technique for those gastric cancer patients who are likely to suffer from peritoneal recurrence. In this paper, we review the effect of EIPL therapy on prevention of peritoneal recurrence on patients with peritoneal free cancer cells without overt peritoneal metastasis (CY+/P−) through the prospective randomized study, and we verified its potential as an optimal and standard prophylactic therapeutic strategy for peritoneal recurrence.

Mouse forestomach carcinoma cells immunosuppress macrophages through transforming growth factor-β1

Peritoneal implantation metastasis of gastric cancer cells is associated with poor prognosis. Peritoneal macrophages are the most important immune cells in the abdominal cavity to control tumor metastasis. In the present study, the immunosuppressive effects of mouse forestomach cells on macrophages were examined. Conditioned medium from mouse forestomach cell cultures were used to treat isolated peritoneal macrophages. A colorimetry-based phagocytosis assay was performed to investigate the functional change of macrophages. The alteration of cytokine secretion by macrophages was measured by ELISA assay. Specific markers of macrophage polarization were analyzed by real-time RT-PCR. TGF-β1 signaling was evaluated by western blotting. Neutralization experiments were performed using an anti-TGF-β1 antibody. Conditioned medium reduced the phagocytotic capability of macrophages. Lower TNF-α and IL-1β levels and higher IL-10 and VEGF levels were observed. Real-time RT-PCR showed increased mRNA levels of M2 macrophage markers. Further study revealed that TGF-β1 was significantly elevated in the conditioned medium and TGF-β1 signaling was activated in the macrophages by the treatment of conditioned medium. Neutralization of TGF-β1 reversed the immunosuppressive effects on macrophages. Immunosuppressive macrophages can be induced by conditioned medium from mouse forestomach cell cultures. These effects appeared to occur through the production of TGF-β1 by the tumor cells. Targeted TGF-β1 intervention may help to control peritoneal metastasis of gastric cancers.

Free peritoneal tumor cells detection in gastric and colorectal cancer patients

BACKGROUND

Free peritoneal tumor cells (FPTC) derive from the detachment of primary cancer and may result in peritoneal carcinomatosis. Since peritoneal lavage cytology has low sensitivity in detecting FPTC, our aim was to estimate the clinical relevance of FPTC detected using an approach based on multiple molecular techniques.

MATERIALS AND METHODS

Samples of peritoneal lavage were collected from 27 gastric and 48 colorectal cancer patients. FPTC recovery and detection from peritoneal washes was performed by cytological examination and immunomagnetic enrichment for epithelial cells followed by immunofluorescence analysis for epithelial marker EpCAM/CD326 and carcinoembryonic antigen (CEA). CEA and CK20 mRNA levels were quantified using a real-time qRT-PCR system.

RESULTS

For gastric carcinoma the FPTC positivity rate acquired by cytology, immunofluorescence and qRT-PCR was 14.8%, 14.8%, and 78% and for colorectal carcinoma was 0%, 17%, and 42%, respectively. qRT-PCR positivity was correlated with a poor cancer-specific survival and time-to-recurrence rates in both gastric and colorectal carcinoma.

CONCLUSIONS

Epithelial immunoenrichment and immunofluorescence analysis allows unequivocal identification of the FPTC. The real time qRT-PCR showed higher sensitivity for the detection of CEA and CK20 mRNA levels and confirmed its prognostic value in gastrointestinal cancers.

Pivotal roles of peptide transporter PEPT1 and ATP-binding cassette (ABC) transporter ABCG2 in 5-aminolevulinic acid (ALA)-based photocytotoxicity of gastric cancer cells in vitro

BACKGROUND

Recently, 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) is being widely used in cancer therapy owing to the tumor-specific accumulation of photosensitizing protoporphyrin IX (PpIX) after the administration of ALA. In the present study, by focusing on genes involved in the porphyrin biosynthesis pathway, we aimed to explore biomarkers that are predictive for the efficacy of ALA-PDT.

METHODS

We used five lines of human gastric cancer cells to measure the ALA-based photocytotoxicity. ALA-induced production of PpIX in cancer cells was quantified by fluorescence spectrophotometry. To examine the potential involvement of PEPT1 and ABCG2 in the ALA-PDT sensitivity, stable cell lines overexpressing PEPT1 were established and ABCG2-specific siRNA used.

RESULTS

We observed that three cell lines were photosensitive, whereas the other two cell lines were resistant to ALA-based photocytotoxicity. The ALA-based photocytotoxicity was found to be well correlated with intracellular PpIX levels, which suggests that certain enzymes and/or transporters involved in ALA-induced PpIX production are critical determinants. We found that high expression of the peptide transporter PEPT1 (ALA influx transporter) and low expression of the ATP-binding cassette transporter ABCG2 (porphyrin efflux transporter) determined ALA-induced PpIX production and cellular photosensitivity in vitro.

CONCLUSION

PEPT1 and ABCG2 are key players in regulating intracellular PpIX levels and determining the efficacy of ALA-based photocytotoxicity against gastric cancer cells in vitro. Evaluation of the expression levels of PEPT1 and ABCG2 genes could be useful to predict the efficacy of ALA-PDT. Primers specific to those target genes are practical and useful biomarkers for predicting the photo-sensitivity to ALA-PDT.

Analysis for the combination expression of CK20, FABP1 and MUC2 is sensitive for the prediction of peritoneal recurrence in gastric cancer

Prediction of peritoneal recurrence in gastric cancer patients is important for application of adjuvant chemotherapy. After surgery, occasional patients have peritoneal recurrence despite negative cytology of the peritoneal washings. Thus, molecular detection of a subliminal number of cancer cells in peritoneal washings may overcome the sensitivity limitation of conventional cytology. In this study, expressions of five specific marker genes, namely, TFF1, TFF2, CK20, FABP1 and MUC2, were evaluated for their usefulness as markers of micro-dissemination. It was found that reverse transcriptase-polymerase chain reaction for these five genes yielded results highly specific for the depth of invasion and disease stage. Furthermore, the expression of CK20, FABP1 and MUC2 was a reliable prognostic indicator of peritoneal metastasis. Our results suggest that evaluation of the expression of CK20, FABP1 and MUC2 in peritoneal washings is a useful tool for identifying patients at high risk of peritoneal recurrence who may need adjuvant chemotherapy.

Blockade of chloride ion transport enhances the cytocidal effect of hypotonic solution in gastric cancer cells

BACKGROUND

Cancer cells that are exfoliated into the peritoneal cavity during surgery are viable and have the potential to produce peritoneal recurrence. Although peritoneal lavage with distilled water is applied in some cancer surgeries to kill tumor cells, there is no consensus regarding the optimal methodology and its effects.

METHODS

Three human gastric cancer cell lines, MKN28, MKN45, and Kato-III, were exposed to distilled water, and the resultant morphologic changes were observed using a microscope. Analysis of cell volume changes was performed using a flow cytometer. To investigate the cytocidal effects of the water, re-incubation of the cells was performed after exposing them to hypotonic solution. Additionally, the effects of 5-nitro-2-3-phenylpropylamino)-benzoic acid (NPPB), a Cl(-) channel blocker, and R(+)-[(dihydroindenyl)oxy] alkanoic acid (DIOA), a blocker of the K(+)/Cl(-) co-transporter, on the cells during their exposure to hypotonic solution were analyzed.

RESULTS

After the cells had been exposed to the distilled water, a rapid increase in cell volume occurred followed by cell rupture. In the MKN45 and Kato-III cells, treatment with NPPB increased cell volume by inhibiting regulatory volume decrease and enhanced the cytocidal effects of the hypotonic solution, whereas no such effects were observed in the MKN28 cells. On the other hand, treatment of the MKN28 cells with DIOA inhibited RVD and enhanced the cytocidal effects of hypotonic shock.

CONCLUSION

These findings support the efficacy of peritoneal lavage with distilled water during surgery for gastric cancer and suggest that the regulation of Cl(-) transport enhances the cytocidal effects of hypotonic shock.

Oncofetal protein, IMP-3, a potential marker for prediction of postoperative peritoneal dissemination in gastric adenocarcinoma

BACKGROUND

The aim of this study was to determine the expression of insulin-like growth factor-II messenger RNA (mRNA)-binding protein-3 (IMP-3) and its clinical significance in gastric cancers, as well the prognostic value of its expression in the peritoneal lavage fluid after surgery.

METHODS

IMP-3 expression was examined by immunohistochemistry in 96 primary gastric tumors. IMP-3 mRNA expression in peritoneal lavage fluid obtained at laparotomy was determine by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

Positive staining for IMP-3 was observed in 74% (71/96) of the tumors. IMP-3 expression in gastric tumors correlated significantly with worst overall survival (OS) and recurrence-free survival. Multivariate analyses identified pathological N stage and IMP-3 expression as significant independent prognostic factors for disease-free survival. Eight (28%) of 36 peritoneal lavage samples were cytologically negative but positive for IMP-3 mRNA expression by RT-PCR. The OS of patients with IMP-3-positive peritoneal lavage was significantly worse than of those with negative expression.

CONCLUSIONS

IMP-3 expression in primary gastric tumors was an independent poor prognostic factor. IMP-3 mRNA expression in peritoneal lavage fluid was a predictor of recurrence after surgery in gastric cancer and a marker of poor prognosis.

Long-term results and prognostic factors of gastric cancer patients with only positive peritoneal lavage cytology

BACKGROUND AND OBJECTIVES

The purpose of the present study was to investigate clinicopathologic features of gastric cancer patients with only positive peritoneal cytology in the absence of overt peritoneal metastases, and which might distinguish patients with poorer prognosis.

METHODS

Between September 1994 and August 2006, clinicopathological features were retrospectively evaluated in 37 consecutive patients with gastric cancer who underwent a curative resection and had positive peritoneal cytology in the absence of overt peritoneal metastases. Survival including disease-free survival (DFS) and overall survival (OS), and recurrence patterns were analyzed according to clinicopathologic characteristics.

RESULTS

The median follow-up period was 16.1 months (range, 3-45 months). The median DFS and OS of patients after curative resection were 10 months (range, 1-33 months) and 15 months (range, 2-45 months), respectively. All patients had recurred, in 34 (92%) with peritoneal dissemination. The overall 1-, 2-, 3-, and 5-year survival rates for the 37 consecutive patients were 43.2%, 45.9%, 5.4%, and 0%, respectively. Multiple linear regression analysis revealed that Borrmann type IV was an independent predictor for poorer prognosis.

CONCLUSIONS

A Borrmann type IV carcinoma may be the candidates for intraperitoneal chemotherapy among advanced gastric cancer patients.

Systematic review of intraperitoneal chemotherapy for gastric cancer

BACKGROUND

Gastric cancer with peritoneal carcinomatosis has a poor prognosis. Intraperitoneal chemotherapy has been proposed as a treatment option. This systematic review examined recent literature to determine the role of intraperitoneal chemotherapy in gastric cancer.

METHODS

Four electronic databases were searched between January 2004 and January 2010 for relevant studies. Defined outcomes of interest were treatment-related morbidity and mortality, long-term survival and sites of recurrence.

RESULTS

Fourteen studies were identified involving 914 patients with gastric cancer, of whom 819 (89·6 per cent) received intraperitoneal chemotherapy. There were two randomized controlled trials, two case-control studies and ten observational studies. Methodological quality was rated as poor in 12 studies, with selection and observer bias apparent in most non-randomized cohorts. Studies were often small and varied in terms of intraperitoneal timing of chemotherapy, chemotherapeutic agents, treatment temperature, and the use of adjuvant therapies. In the better conducted studies, survival was longer in patients receiving intraperitoneal chemotherapy and surgery than in those having surgery alone.

CONCLUSION

There is limited good-quality evidence to determine the role of intraperitoneal chemotherapy in gastric cancer. Intraperitoneal chemotherapy in gastric cancer is worthy of further appraisal. However, the quality of trials must be improved, and studies must be conducted more uniformly to minimize bias and aid comparison between centres.

Intraperitoneal free cancer cells in non-gynaecological adenocarcinomas: a reproducibility study

OBJECTIVE

In recent years, therapeutic approaches including cytoreductive surgery followed by intraperitoneal chemotherapy have proven effective in peritoneal carcinomatosis of colorectal origin. If cytology is to be used to include patients in aggressive treatment regimens, it is necessary to evaluate its performance, particularly in terms of specificity. The aim of this study was to assess interobserver agreement for the detection of intraperitoneal free cancer cells (IFCCs) in patients with non-gynaecological adenocarcinomas.

METHODS

Over a 5-year period, 1223 patients were recruited in 19 French surgery departments. Peritoneal samples were examined in 14 dispersed pathology laboratories. Giemsa-stained slides were sent to a control reader blind to the previous diagnosis. Discordant cases, concordant positive results and a random selection of negative concordant cases were reviewed by a panel of seven cytopathologists. The 'final diagnosis' was that of the consensus meetings but took into account locally-processed slides.

RESULTS

Gathering dubious cases with negative results, a 95.6% concordance was achieved between local readers and the control reader. IFCCs were ascertained by the panel in 85 cases (7.0%). Eight of 873 colorectal cancers cases viewed locally were falsely positive (0.9%). Radiotherapy and neoadjuvant therapy had no impact on the false-positive rate as assessed by final validation by the panel (P > 0.05). Samples initially considered as dubious were reclassified as negative by the panel in 24 of 25 cases (96.0%).

CONCLUSIONS

The panel consensus allowed reclassification of most dubious/equivocal peritoneal cytology cases, whereas clearcut distinction between benign and malignant cases was correctly achieved in almost all cases.

S-1 and the treatment of gastric cancer with peritoneal dissemination

Peritoneal dissemination is the most common metastatic pattern of gastric cancer. We frequently face the necessity for gastrectomy in the event of gastric stenosis or gastric bleeding. However, the indication for palliative gastrectomy and the effectiveness of palliative chemotherapy are not clear. We retrospectively evaluated the prognostic factors after palliative gastrectomy in 121 gastric cancer patients with peritoneal dissemination. The expression of orotate phosphoribosyl transferase (OPRT) was examined immunohistochemically. The median survival time of all patients after palliative gastrectomy was 8.8 months. In the multivariate analyses, we adjusted the data of 82 patients without liver metastases for the background of 5-fluouracil (5-FU)-based chemotherapy regimen. The analysis revealed that the degree of peritoneal dissemination (multiple vs. a few metastases or cytology-positive; P= 0.01) and chemotherapy (S-1 vs. other 5-FU; P=0.01) were independent predictors of survival. Particularly, S-1 treatment was associated with a more favorable prognosis of the patients with high levels of OPRT expression compared to that of the patients with low expression. Patients with peritoneal dissemination are considered as terminal and inoperable. However, S-1 treatment may improve the survival after palliative gastrectomy in patients selected according to the degree of peritoneal dissemination and high OPRT expression.

Surgical outcomes for gastric cancer patients with intraperitoneal free cancer cell, but no macroscopic peritoneal metastasis

BACKGROUND AND OBJECTIVES

Gastric cancer patients with intraperitoneal cancer cells have extremely poor prognoses, because they frequently develop peritoneal metastasis. The aim of the current study is to clarify the clinicopathologic characteristics of patients with intraperitoneal free cancer cells who do not have recurrences.

METHODS

This study examined 1,985 gastric adenocarcinoma patients who underwent gastrectomies at our institution between January 1975 and December 2000.

RESULTS

The 5-year survival rate of advanced gastric cancer patients with intraperitoneal free cancer cells, but no macroscopic peritoneal metastases (P0Cy1), is 15.3%. Multivariate analysis identified only lymph node metastasis as an independent prognostic indicator in P0Cy1 patients. The 5-year survival rates of P0Cy1 patients were 62.5%, 19.1%, 17.6%, and 9.4% in n0, n1, n2, and n3 patients, respectively. Peritoneal recurrence was observed significantly more often in P0Cy1 patients than in advanced gastric cancer patients without intraperitoneal free cancer cells.

CONCLUSIONS

Our data indicate that prognoses of P0Cy1 patients without lymph node metastasis are good, whereas the prognoses of those with lymph node metastasis are extremely poor. Therefore, radical surgery and adequate adjuvant chemotherapy should be performed for P0Cy1 patients with no lymph node metastasis.

Neoadjuvant intraperitoneal and systemic chemotherapy for gastric cancer patients with peritoneal dissemination

BACKGROUND

The present study was designed to assess the feasibility and efficiency of intraperitoneal and intravenous neoadjuvant chemotherapy in gastric cancer patients with peritoneal dissemination.

METHODS

The study subjects were 25 treatment-naïve patients with gastric cancer. Patients with positive cytology or with peritoneal carcinomatosis received neoadjuvant intraperitoneal and systemic chemotherapy (NIPS), comprising intraperitoneal (i.p.) mitomycin C (MMC) and cisplatin (CDDP), followed by two cycles of intravenous triplet chemotherapy of docetaxel, 5-fluorouracil (5-FU), and CDDP. Gastrectomy with lymph node dissection was performed after NIPS in patients free of peritoneal deposits, confirmed by staging laparoscopy.

RESULTS

Seventeen patients had measurable lymph node metastases by the RECIST criteria. CT examination showed response to the treatment in ten (59%, 0 complete response, 10 partial response). Of the 25 patients, 14 (56%) showed negative results on peritoneal cytology with no macroscopic peritoneal metastasis, whereas the remaining 11 were cancer cell-positive on peritoneal cytology or macroscopic peritoneal metastasis even after NIPS. The median survival time for all 25 patients was 16.7 months. Prognosis was better in patients who showed negative cytology and disappearance of peritoneal cancer metastases after NIPS than in those with positive cytology or existing peritoneal deposits (P < 0.0001). The predominant toxicity was myelosuppression and grade 3-4 leukopenia and neutropenia occurred in 20 (80%) patients, which were manageable. No treatment-related mortality was observed during and after NIPS and surgery.

CONCLUSIONS

The results of this prospective phase II study indicated that the newly designed NIPS was highly effective and well tolerated in patients with advanced gastric cancer and peritoneal dissemination.