Peritoneal washing cytology: prognostic value of positive findings in patients with gastric carcinoma undergoing a potentially curative resection

Transcriptomics-based liquid biopsy panel for early non-invasive identification of peritoneal recurrence and micrometastasis in locally advanced gastric cancer

BACKGROUND

This study aimed to develop a novel six-gene expression biomarker panel to enhance the early detection and risk stratification of peritoneal recurrence and micrometastasis in locally advanced gastric cancer (LAGC).

METHODS

We used genome-wide transcriptome profiling and rigorous bioinformatics to identify a six-gene expression biomarker panel. This panel was validated across multiple clinical cohorts using both tissue and liquid biopsy samples to predict peritoneal recurrence and micrometastasis in patients with LAGC.

RESULTS

Through genome-wide expression profiling, we identified six mRNAs and developed a risk prediction model using 196 samples from a surgical specimen training cohort. This model, incorporating a 6-mRNA panel with clinical features, demonstrated high predictive accuracy for peritoneal recurrence in gastric cancer patients, with an AUC of 0.966 (95% CI: 0.944-0.988). Transitioning from invasive surgical or endoscopic biopsy to noninvasive liquid biopsy, the model retained its predictive efficacy (AUC = 0.963; 95% CI: 0.926-1.000). Additionally, the 6-mRNA panel effectively differentiated patients with or without peritoneal metastasis in 95 peripheral blood specimens (AUC = 0.970; 95% CI: 0.936-1.000) and identified peritoneal micrometastases with a high efficiency (AUC = 0.941; 95% CI: 0.874-1.000).

CONCLUSIONS

Our study provides a novel gene expression biomarker panel that significantly enhances early detection of peritoneal recurrence and micrometastasis in patients with LAGC. The RSA model's predictive capability offers a promising tool for tailored treatment strategies, underscoring the importance of integrating molecular biomarkers with clinical parameters in precision oncology.

Peritoneal Washing Cytology Positivity in Gastric Cancer: Role of Lymph Node Metastasis as a Risk Factor

PURPOSE

Peritoneal washing cytology (PWC) is a widely used diagnostic tool for detecting peritoneal metastasis of advanced gastric cancer. However, the prognosis of patients with positive PWC remains poor even after gastrectomy, and treatments vary among institutions and eras. In this study, we identified the clinical factors that can help predict cytology-positive (CY(+)) gastric cancer.

MATERIALS AND METHODS

We retrospectively reviewed the national data of patients with gastric cancer from 2019, as provided by the Information Committee of the Korean Gastric Cancer Association. Of the 13,447 patients with gastric cancer, 3,672 underwent PWC. Based on cytology results, we analyzed the clinicopathological characteristics and assessed the possibility of CY(+) outcomes in relation to T and N stages.

RESULTS

Of the 3,270 patients who underwent PWC without preoperative chemotherapy, 325 were CY(+), whereas 2,945 were negative. CY(+) was more commonly observed in patients with Borrmann type IV gastric cancer, an undifferentiated histological type, and advanced pathological stages. Multivariate analysis revealed Borrmann type IV (odds ratio [OR], 1.821), tumor invasion to T3-4 (OR, 2.041), and lymph node metastasis (OR, 3.155) as independent predictors of CY(+). Furthermore, for circular tumor location, the N stage emerged as a significant risk factor for CY(+), particularly when the tumor was located on the posterior wall (PW) side.

CONCLUSIONS

Lymph node metastasis significantly affects CY(+) outcomes, particularly when the tumor is located on the PW side. Therefore, PWC should be considered not only in suspected serosal exposure cases but also in cases of lymph node metastasis.

Oligometastasis of Gastric Cancer: A Review

The concept of oligometastasis is not yet fully established in the field of gastric cancer. However, metastatic lesions that are localized, technically resectable at diagnosis, present a certain response to preoperative chemotherapy, and present favorable survival outcomes with local treatments, sometimes in combination with chemotherapy, are recognized as oligometastasis in the field of gastric cancer. Oligometastasis is noted in European Society for Medical Oncology guidelines and Japanese gastric cancer treatment guidelines, and local treatment is mentioned as one of the pivotal treatment options for oligometastasis. Solitary liver metastasis or a small number of liver metastases; retroperitoneal lymph node metastasis, especially localized para-aortic lymph node metastasis; localized peritoneal dissemination; and Krukenberg tumor are representative types of oligometastasis in gastric cancer. The AIO-FLOT3 trial prospectively evaluated the efficacy of multimodal treatments for gastric cancer with oligometastasis, including surgical resection of primary and metastatic lesions combined with chemotherapy, confirming favorable survival outcomes. Two phase 3 studies are ongoing to investigate the efficacy of surgical resection combined with perioperative chemotherapy compared with palliative chemotherapy. Thus far, the evidence suggests that multimodal treatment for oligometastasis of gastric cancer is promising.

The contemporary management of peritoneal metastasis: A journey from the cold past of treatment futility to a warm present and a bright future

Peritoneal metastasis (PM) is often regarded as a less frequent pattern of spread; however, collectively across all spectra of primary tumors, the consequences of PM impact a large population of patients annually. Unlike other modes of metastasis, symptoms at presentation or during the treatment course are common, representing an additional challenge in the management of PM. Early efforts with chemotherapy and incomplete surgical interventions transiently improved symptoms, but durable symptom control and survival extension were rare, which established a perspective of treatment futility for PM through most of the 20th century. Notably, the continued development of better systemic therapy combinations, optimization of cytoreductive surgery (CRS), and rigorous investigation of combining regional therapy-specifically hyperthermic intraperitoneal chemotherapy-with CRS, have resulted in more effective multimodal treatment options for patients with PM. In this article, the authors provide a comprehensive review of the data establishing the contemporary approach for tumors with a high frequency of PM, including appendix, colorectal, mesothelioma, and gastric cancers. The authors also explore the emerging role of adding hyperthermic intraperitoneal chemotherapy to the well established paradigm of CRS and systemic therapy for advanced ovarian cancer, as well as the recent clinical trials identifying the efficacy of poly(adenosine diphosphate ribose) polymerase maintenance therapy. Finally, recent data are included that explore the role of precision medicine technology in PM management that, in the future, may help further improve patient selection, identify the best systemic therapy regimens, detect actionable mutations, and identify new targets for drug development.

Three-year outcomes of the randomized phase III SEIPLUS trial of extensive intraoperative peritoneal lavage for locally advanced gastric cancer

Whether extensive intraoperative peritoneal lavage (EIPL) after gastrectomy is beneficial to patients with locally advanced gastric cancer (AGC) is not clear. This phase 3, multicenter, parallel-group, prospective randomized study (NCT02745509) recruits patients between April 2016 and November 2017. Eligible patients who had been histologically proven AGC with T3/4NxM0 stage are randomly assigned (1:1) to either surgery alone or surgery plus EIPL. The results of the two groups are analyzed in the intent-to-treat population. A total of 662 patients with AGC (329 patients in the surgery alone group, and 333 in the surgery plus EIPL group) are included in the study. The primary endpoint is 3-year overall survival (OS). The secondary endpoints include 3-year disease free survival (DFS), 3-year peritoneal recurrence-free survival (reported in this manuscript) and 30-day postoperative complication and mortality (previously reported). The trial meets pre-specified endpoints. Estimated 3-year OS rates are 68.5% in the surgery alone group and 70.6% in the surgery plus EIPL group (log-rank p = 0.77). 3-year DFS rates are 61.2% in the surgery alone group and 66.0% in the surgery plus EIPL group (log-rank p = 0.24). The pattern of disease recurrence is similar in the two groups. In conclusion, EIPL does not improve the 3-year survival rate in AGC patients.

Does Extended Intraoperative Peritoneal Lavage Really Bring Benefit on Patients With Gastric Cancer? A Meta-Analysis of Published Clinical Trials

Purpose

The purpose of the current meta-analysis is to analyze whether extended intraoperative peritoneal lavage (EIPL) can bring benefit on short-term outcomes or survival for patients undergoing curative gastrectomy for gastric cancer.

Methods

The PubMed, Embase, and Cochrane Library databases were searched from inception to May 3, 2021, to find eligible studies. Postoperative complications, overall survival (OS), disease-free survival (DFS), and peritoneal recurrence-free survival (PRFS) were compared between EIPL group and No EIPL group.

Results

A total of five randomized controlled trials with 1,790 patients were included in the current meta-analysis. No difference was found in baseline information (p > 0.05). After pooling up the data of overall postoperative complications, no significant difference was found between EIPL group and No EIPL group (OR = 0.88, 95% CI = 0.51 to 1.53, P = 0.65). Furthermore, there was no significant difference between EIPL group and No EIPL group in terms of OS (HR = 0.77, 95% CI = 0.36 to 1.64, P = 0.49), DFS (HR = 0.97, 95% CI = 0.71 to 1.33, P = 0.87), and PRFS (HR = 1.03, 95% CI = 0.74 to 1.43, P = 0.86). In terms of subgroup analysis of OS, no significant difference was found as well (HR = 1.05, 95% CI = 0.82 to 1.34, P = 0.69).

Conclusions

EIPL did not bring benefit in terms of short-term outcomes or survival. Therefore, EIPL is not recommended for patients undergoing curative gastrectomy for gastric cancer.

The benefits of surgery plus extensive intraoperative peritoneal lavage (EIPL) for patients with gastric cancer compared with surgery alone: a systematic review and meta-analysis

This study aims to synthesize the benefits of surgery plus extensive intraoperative peritoneal lavage (EIPL) for patients with gastric cancer compared with surgery alone. We searched Pubmed, Embase, Web of Science, Cochrane library, ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform (ICTRP) for randomized controlled trials from 2000 to 2021 according to the inclusion and exclusion criteria. The reference lists of studies meeting the criteria were also screened for additional studies. The quality of these studies was assessed by the Cochrane Collaboration Risk of Bias Tool. An inverse-variance random-effects model of DerSimonian and Laird was used to synthesize the HRs and corresponding 95% CIs of short-term outcomes: hospital mortality and postoperative complications. For long-term outcomes (peritoneal recurrence and 3-year or 5-year overall survival rate), narrative synthesis was used. 4 of 43 studies were included for quantitative analysis. For short-term outcomes, the pooled HRs of hospital mortality and postoperative complications are 0.422 (95%CI: 0.037, 4.790) and 0.774 (95%CI: 0.376, 1.592). For long-term outcomes, despite the inconsistent results, patients receiving EPIL did not have reduced peritoneal recurrence and 3-year or 5-year overall survival rate. Compared with surgery alone, surgery plus EIPL does not have more benefits for patients with gastric cancer.

Clinical Significance of Peritoneal Fluid Examination for Free Cancer Cells in Patients Qualified for Surgery for Gastric Cancer

Background: Peritoneal lavage cytology in patients with gastric cancer may correlate with an unfavorable prognosis. This study evaluated the presence of free cancer cells in the peritoneal lavage of a population of patients with gastric cancer and its correlation with the outcome of surgical treatment.

Methods: One hundred patients diagnosed with gastric or gastrointestinal junction adenocarcinoma underwent surgery. In all patients, a cytological and immunohistochemical analysis of peritoneal lavage was performed. Based on the presence of free cancer cells (fcc) at the cytological and immunohistochemical examination of peritoneal lavage, patients undergoing surgery for gastric cancer were divided into two groups: fcc (+) and fcc (–).

Results: A total of 100 patients, 37 women, and 63 men with a median age of 65 years were included in the study. In the entire study group, 16 (16%) patients were positive for the presence of free cancer cells (fcc +) at peritoneal lavage examination. However, in the group of patients who underwent gastrectomy, fcc (+) was found in 10 out of 77 (13%) patients. The presence of cancer cells in peritoneal lavage was a strong predictive factor in an unfavorable outcome after surgery, and 1-year and 2-year patient survival was 34 and 0% in fcc (+) patients and 79 and 59% in fcc (–), respectively. Moreover, the presence of free cancer cells was associated with a five-fold increased risk of death within 2 years after surgery. When analyzing the group of patients undergoing R0/R1 surgery, this difference was even more significant (p < 0.0001).

Conclusions: The presence of free cancer cells in peritoneal lavage may significantly affect the outcome of patients with gastric cancer. Radical surgery in patients with free cancer cells in the peritoneal lavage did not result in a survival advantage. Identification of free cancer cells could help for a better stratification of gastric cancer patients, identifying those patients who could better benefit from a radical surgical treatment, finally improving long-term survival.

Clinicopathological profile and its association with peritoneal disease among gastric cancer patients

BACKGROUND

There are no clinicopathological criteria or test to predict peritoneal metastasis either in primary or recurrent gastric cancer. The early prediction will help in altering or adding other adjuvant potential therapy modalities like HIPEC and maintenance chemotherapy.

METHODS

Paraffin based blocks of 110 gastric tumor specimens were subjected to IHC staining to assess VEGF, Her 2 neu, E cadherin, bcl 2 and p 53 expression and its association with peritoneal disease evaluated.

RESULTS

Her 2 neu uptake was present in 17.3%, bcl-2 expression in 19.1%, P53 expression in 40.9%, VEGF in 41.8% and E cadherin expression in 49.1% patients. On univariate analysis, a younger age(p = .029), female sex(p = .026), positive VEGF expression (p = .001) and p53 expression(p = .015) were significantly associated with peritoneal disease. A binomial logistic regression was performed to ascertain the effects of independent variables evaluated on univariate analysis. Of the 10 predictors variables, only three were statistically significant: tumor type, P53, and VEGF. Positive VEGF expression had 48.7, E cadherin 2.6 and Her2neu 1.5 times higher odds of exhibiting peritoneal disease.

CONCLUSION

A younger age, female sex, distal 2/3rd, diffuse variant, VEGF staining in >10% cells and decrease p53 expression were associated with peritoneal disease.

Impact of preoperative chemotherapy as initial treatment for advanced gastric cancer with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) or localized peritoneal metastasis (P1a): a multi-institutional retrospective study

BACKGROUND

Gastric cancer (GC) patients with peritoneal metastasis are defined as stage IV in the Japanese classification of GC. For patients with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) and/or localized peritoneal metastasis (P1a), gastrectomy followed by S1 monotherapy is one of the most widely accepted therapeutic strategy in Japan. This study investigated the efficacy of preoperative chemotherapy as initial treatment in GC patients with CY1 and/or P1a.

METHODS

We retrospectively reviewed GC patients diagnosed with CY1 and/or P1a at 34 institutions in Japan between 2008 and 2012. Selection criteria were: adenocarcinoma, no distant metastasis except CY1 or P1a, and no prior treatment. The subjects were divided into an Initial-Chemotherapy group and an Initial-Surgery group, according to the initial treatment.

RESULTS

A total of 824 patients were collected and 713 eligible patients were identified for this study. As the initial treatment, 150 patients received chemotherapy (Initial-Cx), and 563 patients underwent surgery (Initial-Sx). Initial-Cx regimens were cisplatin plus S1/docetaxel plus cisplatin plus S1/others (n = 90/37/23). Both overall survival (OS) and progression-free survival (PFS) were similar between the Initial-Cx and Initial-Sx groups (median OS 24.8 and 24.0 months, HR 1.07, 95% CI 0.87-1.3; median PFS 14.9 and 13.9 months, HR 1.04, 95% CI 0.85-1.27). The 5-year OS rates were 22.3% in the Initial-Cx group and 21.5% in the Initial-Sx group.

CONCLUSIONS

Although, the preoperative chemotherapy did not show a survival benefit for GC patients with CY1 and/or P1a, initial-Cx showed favorable survival in patients who converted to P0 and CY0.

Comparison of prognostic impact between positive intraoperative peritoneal and lavage cytologies in colorectal cancer

BACKGROUND

The prognostic value of positive intraoperative peritoneal cytology and lavage cytology, including the differences in their prognostic impact, in colorectal cancer is controversial. We aimed to investigate the prognostic values of positive peritoneal cytology and lavage cytology findings for colorectal cancer and compare their prognostic impact.

METHODS

We retrospectively evaluated 592 clinical stage II-IV colorectal cancer patients who underwent peritoneal cytology (n = 225) or lavage cytology (n = 367) between November 1993 and December 2018. The prognostic factors for cancer-specific survival were identified, and the differences in cancer-specific survival were examined between the patients.

RESULTS

The cytology-positive rate was 10.8% (64/592), 17.8% (40/225), and 6.5% (24/367) in the overall, peritoneal cytology, and lavage cytology groups, respectively. Both positive peritoneal cytology (hazard ratio: 2.196) and lavage cytology (hazard ratio: 2.319) were independent prognostic factors. The peritoneal cytology-positive group showed significantly poorer cancer-specific survival than the cytology-negative group (5-year: 3.5% vs. 59.5%; 10-year: 3.5% vs. 46.1%, p < 0.001). Similar results were obtained for lavage cytology (5-year: 14.1% vs. 73.9%; 10-year: 4.7% vs. 63.5%, p < 0.001). The cancer-specific survival was not significantly different between the peritoneal cytology-positive and lavage cytology-positive groups (p = 0.058). Both positive peritoneal and lavage cytology were associated with poorer cancer-specific survival across all colorectal cancer stages.

CONCLUSIONS

Positive peritoneal and lavage cytology are associated with worse cancer-specific survival in colorectal cancer. The prognostic impact was comparable between positive lavage and peritoneal cytology. Thus, cytology should be a standard assessment modality for colorectal cancer.

Transcriptomic Profiling Identifies a Risk Stratification Signature for Predicting Peritoneal Recurrence and Micrometastasis in Gastric Cancer

PURPOSE

Gastric cancer peritoneal carcinomatosis is fatal. Delay in detection of peritoneal metastases contributes to high mortality, highlighting the need to develop biomarkers that can help identify patients at high risk for peritoneal recurrence or metastasis.

EXPERIMENTAL DESIGN

We performed a systematic discovery and validation for the identification of peritoneal recurrence prediction and peritoneal metastasis detection biomarkers by analyzing expression profiling datasets from 249 patients with gastric cancer, followed by analysis of 426 patients from three cohorts for clinical validation.

RESULTS

Genome-wide expression profiling identified a 12-gene panel for robust prediction of peritoneal recurrence in patients with gastric cancer (AUC = 0.95), which was successfully validated in a second dataset (AUC = 0.86). Examination of 216 specimens from a training cohort allowed us to establish a six gene-based risk-prediction model [AUC = 0.72; 95% confidence interval (CI): 0.66-0.78], which was subsequently validated in an independent cohort of 111 patients with gastric cancer (AUC = 0.76; 95% CI: 0.67-0.83). In both cohorts, combining tumor morphology and depth of invasion further improved the predictive accuracy of the prediction model (AUC = 0.84). Thereafter, we evaluated the performance of the identical six-gene panel for its ability to detect peritoneal metastasis by analyzing 210 gastric cancer specimens (prior 111 patients plus additional 99 cases), which discriminated patients with and without peritoneal metastasis (AUC = 0.72). Finally, our biomarker panel was also remarkably effective for identifying peritoneal micrometastasis (AUC = 0.72), and its diagnostic accuracy was significantly enhanced when depth of invasion was included in the model (AUC = 0.85).

CONCLUSIONS

Our novel transcriptomic signature for risk stratification and identification of high-risk patients with peritoneal carcinomatosis might serve as an important clinical decision making in patients with gastric cancer.

Peritoneal Lavage Tumor DNA as a Novel Biomarker for Predicting Peritoneal Recurrence in Pancreatic Ductal Adenocarcinoma

BACKGROUND

The clinical role of peritoneal lavage cytology (CY) in pancreatic ductal adenocarcinoma (PDAC) remains controversial, partly due to its low sensitivity. This study aimed to develop a new biomarker, defined as peritoneal lavage tumor DNA (ptDNA), using DNAs extracted from peritoneal lavage samples from patients with PDAC.

METHODS

Samples were collected intraoperatively from 89 PDAC patients who underwent pancreatectomy between 2012 and 2017. Droplet digital polymerase chain reaction (PCR) was used to measure ptDNA for detection of KRAS mutations. The ptDNA status and clinical characteristics were retrospectively evaluated.

RESULTS

Positive ptDNA was found in 41 patients, including all 9 patients positive for CY (CY+) and 32 patients negative for CY (CY-). The mutant allele frequency was significantly higher in the CY+ patients than in the CY- patients. The disease-free survival (DFS) and overall survival (OS) were significantly poorer in the high-ptDNA group than in the low-ptDNA group (median DFS, 11.0 vs. 18.8 months; p = 0.007; median OS, 28.7 vs not reached; p = 0.001). The survival curves of DFS and OS in the CY+ group were almost equal to those in the CY- and high-ptDNA group. In a multivariable analysis, ptDNA was an independent predictive factor for DFS (p = 0.025) and OS (p = 0.047). The estimated cumulative incidence of peritoneal recurrence was 45.5% in the high-ptDNA group. The ptDNA biomarker had a much higher sensitivity for peritoneal recurrence than CY, whereas CY had higher specificity.

CONCLUSIONS

As a promising biomarker, ptDNA may predict poor prognosis and peritoneal recurrence in PDAC, resolving the controversy surrounding CY.

The levels of SYT13 and CEA mRNAs in peritoneal lavages predict the peritoneal recurrence of gastric cancer

BACKGROUND

Although peritoneal lavage cytology often serves as a sensitive method to detect free cancer cells in the abdominal cavity, some patients experience peritoneal recurrence despite negative cytology. The aim of this study was to evaluate mRNAs in peritoneal lavage fluid as potential markers for predicting the peritoneal recurrence of gastric cancer (GC).

METHODS

Peritoneal lavage fluid samples were obtained during surgery conducted on 187 patients with GC and from 30 patients with non-malignant disease (controls). The mRNA levels of nine candidate markers were quantified, and analysis of a receiver-operating characteristic curve compared their accuracies. The cutoff was defined as the highest value of the controls.

RESULTS

Synaptotagmin XIII (SYT13) and carcinoembryonic antigen (CEA) mRNA levels were analyzed further. SYT13 levels were significantly associated with shorter peritoneal recurrence-free survival (PRFS) and overall survival. Among patients with negative peritoneal lavage cytology, those positive for either SYT13 or CEA mRNA experienced significantly shorter peritoneal recurrence-free survival compared with those with negative fluid (hazards ratio [HR] 4.21, P = 0.0114; HR 3.53; P = 0.0426, respectively). Univariate analysis revealed that SYT13 and CEA mRNA levels were significant predictors of peritoneal recurrence. Positive levels of both SYT13 and CEA mRNA demonstrated the highest HR for peritoneal recurrence (HR 12.27, P = 0.0064). Multivariable analysis revealed that SYT13 positivity was a significant independent prognostic factor (HR 3.69; 95% confidence interval, 1.18-12.74; P = 0.0246).

CONCLUSIONS

Combined measurement of SYT13 and CEA mRNA levels in peritoneal lavage fluid could serve as a promising approach to predict peritoneal recurrence of GC.

Randomized clinical trial of extensive intraoperative peritoneal lavage versus standard treatment for resectable advanced gastric cancer (CCOG 1102 trial)

BACKGROUND

A survival benefit of extensive intraoperative peritoneal lavage (EIPL) has been reported in patients with gastric cancer with positive peritoneal cytology. The hypothesis of this study was that EIPL may reduce peritoneal recurrence in patients with advanced gastric cancer who undergo surgery with curative intent.

METHODS

This was an open-label, multi-institutional, randomized, phase 3 trial to assess the effects of EIPL versus standard treatment after curative gastrectomy for resectable gastric cancer of T3 status or above. The primary endpoint was disease-free survival (DFS); secondary endpoints were overall survival, peritoneal recurrence-free survival and incidence of adverse events.

RESULTS

Between July 2011 and January 2014, 314 patients were enrolled from 15 institutions and 295 patients were analysed (145 and 150 in the EIPL and no-EIPL groups respectively). The 3-year DFS rate was 63·9 (95 per cent c.i. 55·5 to 71·2) per cent in the EIPL group and 59·7 (51·3 to 67·1) per cent in the control group (hazard ratio (HR) 0·81, 95 per cent c.i. 0·57 to 1·16; P = 0·249). The 3-year overall survival rate was 75·0 (67·1 to 81·3) per cent in the EIPL group and 73·7 (65·9 to 80·1) per cent in the control group (HR 0·91, 0·60 to 1·37; P = 0·634). Peritoneal recurrence-free survival was not significantly different between the two groups (HR 0·92, 0·62 to 1·36; P = 0·676). No intraoperative complications related to EIPL were observed.

CONCLUSION

EIPL did not improve survival or peritoneal recurrence in patients who underwent gastrectomy for advanced gastric cancer. Registration number: 000005907 (http://www.umin.ac.jp/ctr/index.htm).

Efficacy of Postoperative Chemotherapy After Resection that Leaves No Macroscopically Visible Disease of Gastric Cancer with Positive Peritoneal Lavage Cytology (CY1) or Localized Peritoneum Metastasis (P1a): A Multicenter Retrospective Study

BACKGROUND

Gastric cancer (GC) patients with positive peritoneal lavage cytology (CY1) and/or localized peritoneum metastasis (P1a) are defined as stage IV in the 15th edition of the Japanese Classification of Gastric Cancer. In Japan, the most common treatment for patients with CY1 and/or P1a is gastrectomy followed by postoperative chemotherapy.

PATIENTS AND METHODS

Subjects in this multi-institutional retrospective study were GC patients with CY1 and/or P1a who received surgical resection that leaves no macroscopically visible disease. Patients were selected from 34 institutions in Japan between 2007 and 2012. Selection criteria included adenocarcinoma, no distant metastasis except CY1 and P1a, and no prior treatment for GC before surgery.

RESULTS

Among 824 patients registered, 506 were identified as eligible, with a background of P0CY1, P1aCY0, or P1aCY1 (72.5%, 16.0%, and 11.5% of subjects, respectively). Sixty-two patients had not received postoperative chemotherapy (no-Cx), whereas 444 patients had received postoperative chemotherapy: S-1 monotherapy (S-1; n = 267, 52.7%), cisplatin plus S-1 (CS; n = 114, 22.5%), and others (n = 63, 12.6%). Overall survival (OS) was 29.5, 24.7, 25.4 and 9.9 months in the S-1, CS, 'others', and no-Cx groups, respectively [CS vs. S-1: hazard ratio (HR) 1.15, 95% confidence interval (CI) 0.89-1.50; p = 0.275]. In multivariate analysis, OS was similar between the S-1 and CS groups (CS vs. S-1: HR 1.19, 95% CI 0.92-1.55; p = 0.18).

CONCLUSIONS

Postoperative chemotherapy after gastrectomy that leaves no macroscopically visible disease may have some survival benefits for GC patients with CY1 and/or P1a. In contrast, S-1 plus cisplatin seems to have no additional benefit over S-1 treatment alone.

Rapid Staining Using the Shorr Method for Intraoperative Peritoneal Washing Cytology in Advanced Gastric Cancer: a Pilot Study from a Single Institution

PURPOSE

Intraoperative peritoneal washing cytology (PWC) is used to determine treatment strategies for gastric cancer with suspected serosal invasion. However, a standard staining method for intraoperative PWC remains to be established. We evaluated the feasibility of a rapid and simple staining method using Shorr's stain for intraoperative PWC in advanced gastric cancer.

MATERIALS AND METHODS

Between November 2012 and December 2014, 77 patients with clinical T3 or higher gastric cancer were enrolled. The sensitivity, specificity, and concordance between the Shorr staining method and conventional Papanicolaou (Pap) staining with carcinoembryonic antigen (CEA) immunohistochemistry (IHC) were analyzed.

RESULTS

Intraoperative PWC was performed laparoscopically in 69 patients (89.6%). The average time of the procedure was 8.3 minutes, and the average amount of aspirated fluids was 83.3 mL. The average time for Shorr staining and pathologic review was 21.0 minutes. Of the 77 patients, 16 (20.7%) had positive cytology and 7 (9.1%) showed atypical findings; sensitivity and specificity were 73.6% and 98.2% for the Shorr method, and 78.9% and 98.2% for the Pap method with CEA IHC, respectively. Concordance of diagnosis between the 2 methods was observed in 90.9% of cases (weighted κ statistic=0.875) and most disagreements in diagnoses occurred in atypical findings (6/7). In overall survival, there was no significant difference in C-index between the 2 methods (0.459 in Shorr method vs. 0.458 in Pap with CEA IHC method, P=0.987).

CONCLUSIONS

Shorr staining could be a rapid and reliable method for intraoperative PWC in advanced gastric cancer.

A single-institution retrospective analysis of gastric carcinoma with positive peritoneal lavage cytology and without serosal invasion: A case series

BACKGROUND AND OBJECTIVES

Peritoneal dissemination of gastric cancer is often associated with serosal infiltration. The aim of this study was to evaluate the clinical importance of peritoneal lavage cytology in patients with gastric carcinoma without serosal invasion. The incidence and impact on prognosis of positive cytology were analyzed.

METHODS

Of 2768 patients with gastric cancer, outcomes and pathological characteristics of 973 patients were reviewed retrospectively. All patients underwent peritoneal lavage at laparotomy for curative or palliative resection of gastric cancer between 1999 and 2017. Among these, 479 who underwent surgery from January 1999 to March 2012 were also reviewed to analyze 5-year survival.

RESULTS

Of 973 patients enrolled, 338 (35%) did not have serosal invasion, and peritoneal cytology was positive in 4/338 (1.2%). Of these four patients, one had submucosal invasion and three had muscularis propria invasion. Of 635 patients with serosal invasion, peritoneal cytology was positive in 74/635 (12%). Of 479 patients reviewed for survival, cytology was positive in 32/479, with 3/32 (9%) surviving for five years, and cytology was negative in 447 patients with 266/447 (60%) surviving for five years.

CONCLUSIONS

Cytologic evaluation should be routinely performed in patients with early-stage gastric cancer.

Re-emerging role of macroscopic appearance in treatment strategy for gastric cancer

Pathological outcomes are definitely the most important prognostic factors in gastric cancer, but they can be obtained only after surgical resection. Use of preoperative adjuvant chemotherapy is becoming widespread for aggressive human cancer, so clinical factors such as macroscopic features are important as they are highly predictive for patient prognosis. In gastric cancer, the macroscopic type represents a distinct prognosis; Type 0 represents early gastric cancer with excellent prognosis, but, among advanced tumors, giant Type III and Type IV tumors have a dismal prognosis. Japan Clinical Oncology Group (JCOG) Stomach Cancer Study Group adopted macroscopic features as high-risk entities in clinical trials. It makes sense for risk classification to use macroscopic phenotypes because The Cancer Genome Atlas (TCGA) Network has lately subcategorized different histologies associated with specific macroscopic types by the molecular features of the whole genome. Dismal prognosis of Type IV gastric cancer is notorious, but similar prognosis was seen in giant Type III gastric cancer defined as 8 cm or beyond, both of which are unique for their propensity of peritoneal dissemination. In this review, clinical relevance including prognosis of such macroscopic high-risk features will be separately debated in the context of precision medicine and updated prognostic outcomes will be presented under the present standard therapy of curative surgery followed by postoperative S-1 chemotherapy. Moreover, promising emerging novel therapeutic strategies including trimodal potent regimens or intraperitoneal chemotherapy will be described for such aggressive gastric cancer.

Advanced gastric cancer: the value of systemic and intraperitoneal chemotherapy

Several possibilities in treating advanced gastric cancer exist. Radical surgery associated with chemotherapy represents the cornerstone. Which one is more effective among neoadjuvant, adjuvant or perioperative chemotherapy is still a matter of debate. Several innovative results showed the necessity to keep increasingly into consideration the intraperitoneal administration of chemotherapies. Moreover, classical drugs and their ways of administration should be combined with the new ones to improve results. Lastly the prevention of recurrence should be considered: one possibility is to administer intraperitoneal chemotherapy earlier in the therapeutic algorithm. (www.actabiomedica.it)

Oncological safety of use of ultrasonic activated shears in gastric cancer surgery: Long-term results of randomized controlled trial

Objective

Ultrasonically activated shears (UAS) have been applied in open gastric surgeries with no or little evidence. It was previously reported about the surgical outcome and effectiveness of UAS based on a randomized controlled trial of 256 patients with gastric cancer. We aimed to clarify the long-term oncological safety of the use of UAS in the aspect of overall survival and recurrence.

Methods

Gastric cancer patients who underwent gastrectomy with D2 lymph node dissection were enrolled and randomly assigned to either the conventional surgery group (n=125) or the UAS group (n=128). Survival, recurrence and long-term postoperative complications were compared between the two groups. The median follow-up period was 56 months.

Results

Gastric cancer-related death was higher in patients of the UAS group compared with the conventional group (P=0.019). Overall survival rates stratified by stage were not significantly different between the two groups (P=0.170). Disease-free survival rates stratified by stage and recurrence-free survival rates of gastric cancer were similar between the conventional group and the UAS group (P=0.313 and 0.199, respectively). The postoperative complication rate was not significantly different between the groups (P=1.000).

Conclusions

It is suggested that the use of UAS in gastrectomy for gastric cancer showed oncologically acceptable safety compared with conventional electric instruments even in long-term period.

S100A4-MYH9 Axis Promote Migration and Invasion of Gastric Cancer Cells by Inducing TGF-β-Mediated Epithelial-Mesenchymal Transition

Driver genes conducing to peritoneal metastasis in advanced gastric cancer remain to be clarified. S100A4 is suggested to evolve in metastasis of gastrointestinal cancer, we aim to explore the role of S100A4 plays in metastasis of advanced gastric cancer and the potential mechanism. Transfection of siRNA or cDNA was applied to alter the expression of protein S100A4 and MYH9, investigation of the expression of epithelial and mesenchymal transition (EMT) associated markers was followed. Cell migration assay was used to screen the alteration of migration ability regulated by S100A4 and MYH9. IHC analysis for tissue sample microarray was performed to reveal their relationship with clinical pathological parameters and potential capacity of predicting survival. Consistent overexpression of S100A4 and MYH9 were found in peritoneal metastasis and primary site compared with adjacent normal tissue. Low expression of S100A4 led to increased epithelial markers as wells as decline of mesenchymal makers, while overexpression of S100A4 led to inverse impact. S100A4 expression was closely correlated with increased migration ability and EMT process induced by TGF-β stimulation. Interference of S100A4 led to downregulation of MYH9 and inactivation of Smad pathway through participating in EMT process, which could be reversed by overexpression of MYH9. Moreover, co-expression of S100A4 and MYH9 was identified in tissue microarray and confirmed by immunofluorescence assay. In conclusion, overexpression of S100A4 and downstream molecular MYH9 in advanced gastric cancer predicted poor prognosis; oncogene S100A4 facilitate EMT process induced by TGF-β stimulation, suggesting a potential target in management of peritoneal metastasis of gastric cancer.

Integrated fluorescent cytology with nano-biologics in peritoneally disseminated gastric cancer

Gastric cancer patients positive for peritoneal cytology are at increased risk of tumor recurrence, but although a certain proportion of cytology‐positive patients relapse rapidly with aggressive progression, others survive longer with conventional chemotherapies. This heterogeneity makes it difficult to stratify patients for more intensive therapy and poses a substantial challenge for the implementation of precision medicine. We developed a new approach to identify biologically malignant subpopulations in cytology‐positive gastric cancer patients, using a green fluorescent protein (GFP)‐expressing attenuated adenovirus in which the telomerase promoter regulates viral replication (TelomeScan, OBP‐401). The fluorescence emitted from TelomeScan‐positive cells was successfully quantified using a multi‐mode microplate reader. We then analyzed clinical peritoneal washes obtained from 68 gastric cancer patients and found that patients positive for TelomeScan had a significantly worse prognosis. In 21 cytology‐positive patients, the median survival time of those who were TelomeScan positive (235 days) was significantly shorter than that for those who were TelomeScan negative (671 days; P = 0.0062). This fluorescent virus‐guided cytology detects biologically malignant cancer cells from the peritoneal washes of gastric cancer patients and may thus be useful for both therapy stratification and precision medicine approaches based on genetic profiling of disseminated cells.

Surgery with curative intent for stage IV gastric cancer: Is it a reality of illusion?

Gastric cancer with metastases outside of the regional lymph nodes is deemed oncologically unresectable. Nevertheless, some metastatic lesions are technically resectable by applying established surgical techniques such as para-aortic lymphadenectomy and hepatectomy. At the time of compilation of the Japanese gastric cancer treatment guidelines version 4, systematic reviews were conducted to see whether it is feasible to make any recommendation to dissect both the primary and metastatic lesions with intent to cure, possibly as part of multimodality treatment. Long-term survivors were found among carefully selected groups of patients both in prospective and retrospective studies. In addition, there is a growing list of publications reporting encouraging outcomes of gastrectomy conducted after exceptionally good response to chemotherapy, usually among patients who underwent R0 resection. This type of surgery is often referred to as conversion surgery. It is sometimes difficult to define a clear borderline between curative surgery scheduled after neoadjuvant chemotherapy and the conversion surgery. This review summarizes what we knew after the literature reviews conducted at the time of compiling the Japanese guidelines and in addition reflects some new findings obtained thereafter through clinical trials and retrospective studies. Metastases were divided into three categories based on the major metastatic pathways: lymphatic, hematogenous, and peritoneal. In each of these categories, there were findings that could provide hope for patients with metastatic disease. These findings implied that the surgical technique that we already use could become more useful upon further developments in antineoplastic agents and drug delivery.

RT-PCR of peritoneal washings predicts peritoneal pancreatic cancer recurrence

BACKGROUND

Peritoneal recurrence of pancreatic cancer is a frequent and lethal outcome after R0 resection. A method to predict peritoneal recurrence could be helpful in its prevention.

MATERIALS AND METHODS

Peritoneal washings were prospectively obtained from 29 patients in whom R0 resection was performed. Cytological examination (CY) and real-time reverse transcription polymerase chain reaction (RT-PCR) of the peritoneal washing for the detection of cancer-related genes, CEACAM5, KRT7, KRAS, and MUC1, were performed. Clinicopathological characteristics and real-time RT-PCR results of the peritoneal washing were compared between patients whose pancreatic cancer recurred peritoneally (n = 7) and those patients who it did not recur (n = 22).

RESULTS

Only one CY-positive (CY⁺) case was detected, and that patient recurred. MUC1 mRNA expression was significantly higher in the recurrence group (P = 0.015). Cumulative incidence-function analysis demonstrated that peritoneal recurrence rate was significantly higher in MUC1-positive (MUC1⁺) patients (P = 0.044). MUC1⁺ patients had significantly decreased disease-free survival (P = 0.009) and disease-specific survival (P = 0.031). MUC1 protein was detected in the primary tumor in 18 of 29 patients. However, no significant difference was observed in the expression of MUC1 protein in peritoneal washings from the primary tumor (P = 0.579).

CONCLUSIONS

High expression of MUC1 mRNA in peritoneal washings is a significant risk factor for peritoneal recurrence of pancreatic cancer after R0 resection along with poor disease-specific survival. RT-PCR of MUC1 mRNA in peritoneal washing may be useful for individualization of adjuvant chemotherapy.

Whole-exome sequencing to identify somatic mutations in peritoneal metastatic gastric adenocarcinoma: A preliminary study

Peritoneal metastasis occurs in more than half of patients with unresectable or recurrent gastric cancer and is associated with the worst prognosis. The associated genomic events and pathogenesis remain ambiguous. The aim of the present study was to characterize the mutation spectrum of gastric cancer with peritoneal metastasis and provide a basis for the identification of new biomarkers and treatment targets. Matched pairs of normal gastric mucosa and peritoneal tissue and matched pairs of primary tumor and peritoneal metastasis were collected from one patient for whole-exome sequencing (WES); Sanger sequencing was employed to confirm the somatic mutations. G>A and C>T mutations were the two most frequent transversions among the somatic mutations. We confirmed 48somatic mutations in the primary site and 49 in the peritoneal site. Additionally, 25 non-synonymous somatic variations (single-nucleotide variants, SNVs) and 2 somatic insertions/deletions (INDELs) were confirmed in the primary tumor, and 30 SNVs and 5 INDELs were verified in the peritoneal metastasis. Approximately 59% of the somatic mutations were shared between the primary and metastatic site. Five genes (TP53, BAI1, THSD1, ARID2, and KIAA2022) verified in our study were also mutated at a frequency greater than 5%in the COSMIC database. We also identified 9genes (ERBB4, ZNF721, NT5E, PDE10A, CA1, NUMB, NBN, ZFYVE16, and NCAM1) that were only mutated in metastasis and are expected to become treatment targets. In conclusion, we observed that the majority of the somatic mutations in the primary site persisted in metastasis, whereas several single-nucleotide polymorphisms occurred de novo at the second site.

Prognostic significance, diagnosis and treatment in patients with gastric cancer and positive peritoneal washings. A review of the literature

Peritoneal dissemination is a common consequence of a relapse following a radical surgical treatment of gastric cancer. The development of the disease in the peritoneum depends not only on its stage, but also on free cancer cells exfoliated from the tumor mass or from involved lymph nodes, and which are capable of being implanted in the peritoneum. According to the latest TNM (7 edition; 2010) classification, patients with free cancer cells in the peritoneal washings qualify for stage IV of the disease. Patients in whom free cancer cells were found during the operation - have a recurrence of gastric cancer - mainly in the peritoneum, and the majority of them die within two years of the diagnosis. To properly assess the prognosis, it is vital to determine the stage of cancer by additionally assessing the washings for the presence of free cancer cells before taking a therapeutic decision. This also allows identifying those patients who require different medical procedures to obtain the best treatment results possible. Medical literature describes various methods of examining peritoneal washings aimed at detecting free cancer cells. The methods apply different cancer cell detection rates, sensitivity and specificity in prediction of a peritoneal relapse. Oncological Departments performing the evaluation of the washings employ non-standard methods of treatment in this group of patients and the results presented are promising.

Intraoperative peritoneal lavage cytology offers prognostic significance for gastric cancer patients with curative resection

Outcomes of patients with gastric cancer who exhibit positive peritoneal lavage cytology findings (CY⁺ ) vary by diagnostic methods because of quantitative and qualitative cancer cell diversity. This study sought to establish practical diagnostic criteria for performing curative resections, based on peritoneal lavage cytology findings in gastric cancer patients. We enrolled 1028 patients with gastric cancer who underwent R0/1 (n = 911) or R2 (n = 117) resections and analyzed relationships between cancer cell findings in peritoneal lavage fluid and clinicopathological factors in the R0/1 group. We found 68 patients with CY⁺ status. Receiver operating characteristic analyses and multivariate analyses showed that the presence of ≥1 signet ring cell, ≥5 cell clusters or ≥50 isolated cancer cells in peritoneal lavage fluid predicted poor prognoses in the 68 CY⁺ patients. High-risk CY⁺ group patients with at least one of the above predictors had the highest hazard ratio (HR = 3.28, P < 0.001). The remaining (low-risk) patients had a survival curve similar to that of patients with a normal cytology. The high-risk CY⁺ patients who underwent R1 resection had poor prognoses despite no macroscopic peritoneal metastasis (2% 5-year survival)-equivalent to that of patients who underwent R2 resection. The CY⁺ criteria defined in this study could help identify candidates for curative resection as an initial therapy for gastric cancer.

Detection value of free cancer cells in peritoneal washing in gastric cancer: a systematic review and meta-analysis

Intraperitoneal free cancer cells in gastric adenocarcinoma are associated with a poor outcome. However, the true prognostic value of intraperitoneal free cancer cells is still unclear, leading to a lack of consensus in the management of gastric cancer. The aim of the present study is to perform a systematic review and meta-analysis to analyze intraperitoneal free cancer cells-positive patients with regard to tumor oncologic stage, recurrence, grade of cellular differentiation, and survival rates and to analyze the clinical significance of intraperitoneal free cancer cells with regard to prognosis. Databases were searched up to January 2016 for prognostic factors associated with intraperitoneal free cancer cells, including oncologic stage, depth of neoplasm invasion, lymph nodal spread, differentiation grade of the tumor, and recurrence and survival rates. A total of 100 studies were identified. Meta-analysis revealed a clear association between intraperitoneal free cancer cells and a poor prognosis. intraperitoneal free cancer cells -positive patients had higher rates of nodal spread (risk difference: 0.29; p<0.01), serosal invasion (risk difference: 0.43; p<0.01), recurrence (after 60 months of follow-up, risk difference: 0.44; p<0.01), and mortality (after 60 months of follow-up, risk difference: 0.34; p<0.01). Intraperitoneal free cancer cells are associated with a poor outcome in gastric cancer. This surrogate biomarker should be used to guide therapy both prior to and after surgery.

Ultrasonically Activated Shears Reduce Blood Loss without Increasing Inflammatory Reactions in Open Distal Gastrectomy for Cancer: A Randomized Controlled Study

BACKGROUND

Previous studies regarding ultrasonically activated shears (UAS) were performed without controlled surgical procedures or consideration of potential thermal injury due to high temperature of active blade of UAS. The purpose of this study was to evaluate the efficacy and safety of UAS through a comparison with conventional monopolar electrocautery (CME) in open distal gastrectomy for gastric cancer.

METHODS

From October 2011 to November 2012, 56 gastric cancer patients eligible for open distal gastrectomy were randomized into UAS or CME groups. Primary endpoints were estimated blood loss (EBL) during surgery and amount of drainage through the fifth postoperative day. Secondary endpoints were operation time, length of hospital stay, postoperative morbidity, changes in cytokine levels in serum, peritoneal irrigation saline, and peritoneal drainage, and inflammatory markers of serum. (Registration-number of ClinicalTrials.gov: NCT01971775).

RESULTS

EBL was lower in the UAS group than that in the CME group (339.8 ± 201.2 vs. 428.6 ± 165.8 mL, p = 0.021). However, the amount of postoperative drainage was not significantly different between the two groups. Although the complication rate was not different between the two groups, there were three cases of intra-abdominal bleeding requiring transfusion only in the CME group. Inflammatory markers from the cytokine assays and serum laboratory tests showed no significant differences between the two groups.

CONCLUSIONS

UAS reduced EBL without increasing inflammatory reactions.

Prognostic significance of CEA expression by RT-PCR in peritoneal wash from patients with gastric cancer: result of a 5-year follow-up after curative resection

OBJECTIVE

Peritoneal recurrence is the most common cause of death after surgery for gastric cancer. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis has been used to detect free cancer cells in peritoneal wash during surgery. This study was conducted to evaluate the prognostic significance of carcinoembrionic antigen (CEA) mRNA detected by RT-PCR in peritoneal wash from patients with gastric cancer after curative resection through a 5-year follow-up.

MATERIALS AND METHODS

Peritoneal wash were obtained from 117 patients who underwent curative surgery for gastric cancer. The association between the CEA RT-PCR results, clinicopathological factors, and factors affecting gastric cancer recurrence were evaluated.

RESULTS

Among the 117 cases, 38 (32.5%) revealed positive CEA expression. Patients with positive CEA expression showed a higher rate of peritoneal recurrence than those with negative CEA expression (p = 0.047). Depth of invasion, lymph node metastasis, TNM stage, and CEA expression were factors affecting recurrence. CEA expression and depth of invasion were significant prognostic factors in a multivariate analysis, and CEA expression was the most important prognostic factor for recurrence in patients who had undergone curative resection for gastric cancer (hazard ratio: 2.747, p = 0.046).

CONCLUSIONS

CEA expression in the peritoneal wash was significantly associated with peritoneal recurrence and was the most important prognostic factor for gastric cancer recurrence after curative resection.

Localized pancreatic cancer with positive peritoneal cytology as a sole manifestation of metastatic disease: a single-institution experience

BACKGROUND

Pancreatic cancer patients with positive peritoneal cytology (PPC) as a sole metastatic site are poorly characterized. Whether they behave similarly to other stage IV patients is unknown.

METHODS

Patients with stage IV disease at our institution between 2003 and 2013 were identified. Inclusion criteria for PPC cohort were PPC at laparoscopy and no laparoscopic and/or radiographic evidence of metastasis. Patients with gross metastasis had laparoscopic and/or radiographic evidence of metastasis.

RESULTS

Among 308 patients, 43 patients had PPC and 265 had gross metastasis. PPC cohort: 3 (7%) resectable, 8 (19%) borderline resectable, and 32 (74%) unresectable tumor. Disease progression occurred in 37 (86%). Sixteen of 43 (37%) also received local therapy (1 surgery and 15 chemoradiation). PPC vs gross metastasis cohort differed as follows: baseline Ca 19-9 (440 vs 1,904 IU/mL, P < .0001); Eastern Cooperative Oncology Group (ECOG) score ≤1 (98 vs 88%, P = .04); median overall survival (13.9 vs 9.4 months, P = .0001).

CONCLUSIONS

Patients with PPC failed to display long-term disease-free survival, although overall survival was superior compared with those with gross metastasis. Patients with PPC may need to be considered a specific subgroup for staging and survival analysis.

Positive Peritoneal Lavage Cytology -Implications for Staging and Management of Gastric Cancer

The survival rates of gastric cancer patients with cytology-positive peritoneal lavage fluid without macroscopic dissemination (CY+/P-) is the same as that of patients with overt peritoneal metastasis.The 5-year survival rate of such patients is only 2%. The current study aims to highlight its significance in the staging of gastrointestinal malignancies and its implications for patient care. Prospective nonrandom analysis of peritoneal wash cytology in patients with gastrointestinal malignancies was conducted in the department of Surgical Gastroenterology, Nizams Institute of Medical Sciences, Hyderabad from January 2012 to June 2013. Descriptive statistics and ANOVA variance analysis was performed to estimate incidence, risk factors and the effect of surgery in causing peritoneal dissemination of malignancy. A total of 60 patients with operable gastric cancer underwent peritoneal lavage for evaluation of malignant cells. The incidence of Positive peritoneal lavage cytology was 8.3% (5/60).Four patients with positive lavage fluid belong to T3 stage (11.7%, p-0.309).Poorly differentiating and mucinous tumors had a higher incidence of positive cytology (18.1% and 25%).None of the patients with positive cytology had positive resection margin. Tumors with advanced T stage, lymph nodal involvement, lympho-vascular and perineural invasion have higher incidence of positive peritoneal cytology. Surgical handling has a negligible effect in peritoneal dissemination of tumor. Large scale studies are warranted to validate the findings and define it's role in management of gastric cancer.

The Role of Hyperthermic Intraperitoneal Chemotherapy in Gastric Cancer

Peritoneal metastasis, either synchronous or metachronous, is commonly seen in gastric cancer. It is associated with a poor prognosis, with a median survival of less than one year. The outcomes are not significantly improved by the use of systemic chemotherapy. We review the relevant literature on the role of HIPEC in gastric cancer. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has been used in three situations in gastric cancer. Besides its role as a definitive treatment in patients with established peritoneal metastasis (PM), it has been used as a prophylaxis against peritoneal recurrence after curative surgery and also as a palliative treatment in advanced peritoneal metastasis with intractable ascites. While prophylactic HIPEC has been shown to reduce peritoneal recurrence and improve survival in many randomised trials, palliative HIPEC can reduce the need for frequent paracentesis. Although CRS with HIPEC has shown promise in increasing the survival of selected patients with established PM from gastric cancer, larger studies are needed before this can be accepted as a standard of care.

Analysis of surgery for incurable gastric cancer

BACKGROUND

It is important to evaluate the curability of and avoid unnecessary exploratory surgery for gastric cancer preoperatively. However, no related research has been reported until now. The aim of this study was to evaluate the factors influencing surgery for incurable gastric cancer.

METHODS

310 cases of T3-4 gastric cancer patients were analyzed retrospectively, including 141 cases with radical surgery and 169 with surgery for incurable gastric cancer. The incurable factors were categorized as T status (unresectable T4 tumor), N status (unresectable lymph node), peritoneal metastasis, and distant metastasis. χ (2) test and logistic regression were performed to analyze the associations between curability, T status, N status, peritoneal metastasis, or distant metastasis and clinicopathological data.

RESULTS

Esophageal involvement and T grade were associated with curability. Cardia involvement and Borrmann type were associated with T status. Esophageal involvement and T grade were associated with N status. Gastric body involvement, esophageal involvement, and T grade were associated with peritoneal metastasis. Gastric antrum involvement was associated with distant metastasis.

CONCLUSIONS

The influencing factors of surgery for incurable gastric cancer should be analyzed preoperatively. Resectability should be evaluated according to these influencing factors combined with imaging analysis.

Prognosis of gastric adenocarcinoma patients with various burdens of peritoneal metastases

BACKGROUND

Peritoneal metastases (PM) in patients with gastric adenocarcinoma (GAC) may be identified by diagnostic laparoscopy (DL) or imaging (I). Although prognosis is poor, some patients have excellent outcome. We compared the overall survival (OS) of patients in 3 groups: those with positive cytology (CY+) by DL (DL-CY+), those with gross PM (GPM) by DL (DL-GPM+) and with GPM obvious on I (I-GPM+).

METHODS

146 GAC patients were identified. The Kaplan-Meier analysis, univariate, and multivariate Cox proportional hazards regression models were employed.

RESULTS

Patients were primarily men (67%), with good ECOG scores (0-1; 89%), had DL (84%), had poorly differentiated GAC (92%), and had received chemotherapy (89%). The median OS for all patients was 15 months (5% CI, 12.9-18.2 months). The DL-CY+ group had median OS of 22.5 months (95% CI, 15-29.3 months). Patients with I-GPM+ had four times the risk of death than those with DL-CY+ (P < 0.001) and patients with DL-GPM+ had two times the risk of death than those with DL-CY+ (P = 0.001). At 36 months, all DL-GPM+ and I-GPM+ had died but 8 patients with DL-CY+ remained alive.

CONCLUSIONS

Some GAC patients with DL-CY+ have long OS; therefore, novel strategies to further prolong their OS are needed.

Free intraperitoneal tumor cells and outcome in gastric cancer patients: a systematic review and meta-analysis

PURPOSE

Despite continuously improving therapies, gastric cancer still shows poor survival in locally advanced stages with local recurrence rates of up to 50% and peritoneal recurrence rates of 17% after curative surgery. We performed a systematic review with meta-analyses to clarify whether positive intraperitoneal cytology (IPC) indicates a high risk of disease recurrence and poor overall survival in gastric cancer.

METHODS

Multiple databases were searched in December 2014 to identify studies on the prognostic significance of positive intraperitoneal cytology in gastric cancer, including: Medline, Biosis, Science Citation Index, Embase, CCMed and publisher databases. Hazard ratios (HR) and associated 95% confidence intervals (CI) were extracted from the identified studies. A meta-analysis was performed using a random-effects model on overall survival, disease-free survival and peritoneal recurrence free survival.

RESULTS

A total of 64 studies with a cumulative sample size of 12,883 patients were included. Cytology, quantitative real time polymerase chain reaction (PCR) or both were performed in 35; 21 and 8 studies, respectively. Meta analyses revealed free intraperitoneal tumor cells (FITC) to be associated with poor overall survival in univariate (HR 3.27; 95% CI 2.82 - 3.78]) and multivariate (HR 2.45; 95% CI 2.04 - 2.94) analysis and poor peritoneal recurrence free survival in univariate (4.15; 95% CI 3.10 - 5.57) and multivariate (3.09; 95% CI 2.02 - 4.71) analysis. Subgroup analysis showed this effect to be independent of the detection method, Western or Asian origin or the time of publication.

CONCLUSIONS

FITC oder positive peritoneal cytology is associated with poor survival and increased peritoneal recurrence in gastric cancer.

Long non-coding RNA LINC01296 is a potential prognostic biomarker in patients with colorectal cancer

Colorectal cancer (CRC), one of the most malignant cancers, is currently the fourth leading cause of cancer deaths worldwide. Recent studies indicated that long non-coding RNAs (lncRNAs) could be robust molecular prognostic biomarkers that can refine the conventional tumor-node-metastasis staging system to predict the outcomes of CRC patients. In this study, the lncRNA expression profiles were analyzed in five datasets (GSE24549, GSE24550, GSE35834, GSE50421, and GSE31737) by probe set reannotation and an lncRNA classification pipeline. Twenty-five lncRNAs were differentially expressed between CRC tissue and tumor-adjacent normal tissue samples. In these 25 lncRNAs, patients with higher expression of LINC01296, LINC00152, and FIRRE showed significantly better overall survival than those with lower expression (P < 0.05), suggesting that these lncRNAs might be associated with prognosis. Multivariate analysis indicated that LINC01296 overexpression was an independent predictor for patients' prognosis in the test datasets (GSE24549, GSE24550) (P = 0.001) and an independent validation series (GSE39582) (P = 0.027). Our results suggest that LINC01296 could be a novel prognosis biomarker for the diagnosis of CRC.

Factors predicting peritoneal recurrence in advanced gastric cancer: implication for adjuvant intraperitoneal chemotherapy

BACKGROUND

Despite adjuvant chemotherapy, patients with advanced gastric cancer (AGC) often develop recurrence, and the peritoneum is the most common site of recurrence. Therefore, intraperitoneal chemotherapy (IPC) has been proposed as a treatment option. The aim of this study was to select the eligible patients for application of IPC.

METHODS

A total of 805 patients with AGC who underwent curative D2 gastrectomy between May 2003 and December 2009 were included in this study. Risk factors for peritoneal recurrence were analyzed.

RESULTS

Recurrence developed in 245 patients (30.4 %). The first site of recurrence was the peritoneum in 144 patients (58.8 %), and the 5-year peritoneal recurrence-free survival was 79.3 %. Depth of tumor invasion ≥T3, extensive lymph node metastasis (N3), Bormann type 4, infiltrative type (Ming's classification), and venous invasion were independent risk factors for peritoneal recurrence. In subgroup analysis with patients who had received adjuvant chemotherapy (n = 481), depth of tumor invasion ≥T3, Bormann type 4, infiltrative type (Ming's classification), and venous invasion were independent risk factors for peritoneal recurrence. When a peritoneal recurrence risk index was made with each risk factor assigned 1 point (2 points for T4 stage), peritoneal recurrence rates with 0, 1, 2, 3, 4, or 5 points were 0 %, 3.9 %, 13.1 %, 33.3 %, 44.0 %, and 72.0 %, respectively, in those patients.

CONCLUSIONS

Patients at higher risk for peritoneal recurrence can be identified from the findings of this study. Further prospective studies are required to evaluate the usefulness of IPC for these patients.

Ultrasonically activated shears versus electrocautery in open gastrectomy for gastric cancer: a randomized controlled trial

BACKGROUND

Use of ultrasonically activated shears (UAS) is gaining popularity in open surgery but without concrete evidence. We conducted a prospectively randomized study to assess the efficacy of ultrasonic dissection in open gastrectomy for gastric cancer.

METHODS

Patients with gastric cancer who were to undergo gastrectomy with D2 lymph node dissection were enrolled and assigned to either the conventional surgery group (n = 125) or the UAS group (n = 128).

RESULTS

The mean operating time was significantly reduced in the UAS group (89.3 ± 15.6 min) when compared to the conventional group (97.8 ± 17.2 min; p < 0.001). However, we did not find any significant difference in operative blood loss, the amount of postoperative abdominal drainage, or the rate of postoperative complications between the groups. A multivariate analysis for operating time revealed that the use of UAS, female gender and BMI less than 25 were significantly associated with reduced operating time. The operating time was significantly longer in the conventional group than in the UAS group (B 7.786; 95 % CI 4.103-11.468; p < 0.001). In the subgroup analysis, the use of UAS significantly reduced the operating time, especially in male patients, regardless of the BMI status.

CONCLUSIONS

The use of UAS in gastrectomy for gastric cancer was a safe and efficient method, especially in terms of reducing operating time for male patients.

Impact of Intraoperative Macroscopic Diagnosis of Serosal Invasion in Pathological Subserosal (pT3) Gastric Cancer

Purpose

The macroscopic diagnosis of tumor invasion through the serosa during surgery is not always distinct in patients with gastric cancer. The prognostic impact of the difference between macroscopic findings and pathological diagnosis of serosal invasion is not fully elucidated and needs to be re-evaluated.

Materials and Methods

A total of 370 patients with locally advanced pT2 to pT4a gastric cancer who underwent curative surgery were enrolled in this study. Among them, 155 patients with pT3 were divided into three groups according to the intraoperative macroscopic diagnosis of serosal invasion, as follows: serosa exposure (SE)(-) (no invasion, 72 patients), SE(±) (ambiguous, 47 patients), and SE(+) (definite invasion, 36 patients), and the clinicopathological features, surgical outcomes, and disease-free survival (DFS) were analyzed.

Results

A comparison of the 5-year DFS between pT3_SE(-) and pT2 groups and between pT3_SE(+) and pT4a groups revealed that the differences were not statistically significant. In addition, in a subgroup analysis of pT3 patients, the 5-year DFS was 75.1% in SE(-), 68.5% in SE(±), and 39.4% in SE(+) patients (P<0.05). In a multivariate analysis to evaluate risk factors for tumor recurrence, macroscopic diagnosis (hazard ratio [HR], SE(-) : SE(±) : SE(+)=1 : 1.01 : 2.45, P=0.019) and lymph node metastasis (HR, N0 : N1 : N2 : N3=1 : 1.45 : 2.20 : 9.82, P<0.001) were independent risk factors for recurrence.

Conclusions

Gross inspection of serosal invasion by the surgeon had a strong impact on tumor recurrence in gastric cancer patients. Consequently, the gross appearance of serosal invasion should be considered as a factor for predicting patients' prognosis.

Preoperative tumor size is a critical prognostic factor for patients with Borrmann type III gastric cancer

PURPOSE

This study was designed to clarify whether preoperative tumor size is an independent prognostic factor (IPF) for patients with Borrmann type III gastric cancer.

METHODS

The study group comprised 350 patients with Borrmann type III gastric cancer. We performed a log-rank plot analysis to establish the threshold value of preoperative tumor size for the prediction of overall survival (OS). Factors with P < 0.10 on univariate prognostic analyses for OS were put into a Cox's proportional hazards model to identify the IPFs.

RESULTS

Peritoneal lavage cytology (CY) was the strongest IPF for patients with Borrmann type III gastric cancer (P < 0.0001). We were able to measure the tumor size preoperatively in 135 patients with negative CY results (CY0). The cutoff tumor size for the prediction of OS was 5.3 cm. A Cox's proportional hazards model showed that pathological lymph-node metastasis (P = 0.007) and preoperative tumor size (P = 0.018) were significant IPFs in the CY0 patients. Patients with a preoperative tumor size of <5.3 cm had satisfactory outcomes, with a 5-year OS rate of >80 %.

CONCLUSIONS

Preoperative tumor size is an IPF for patients with Borrmann type III gastric cancer and CY0. Thus, preoperative tumor size may be a useful factor for deciding on whether neoadjuvant chemotherapy is indicated.

Analysis of exfoliated gastric carcinoma cells attached on surgical supplies

Surgery is considered to have a leading role in the treatment of gastric carcinoma. Surgical supplies are used to cut, divide, and ligate during surgery, and are not only in close contact with normal tissues, but may also be contaminated by pathological tissues and cells. This study sought to determine the presence of exfoliated tumor cells on surgical supplies at different stages during the surgical procedure. We collected five types of surgical supplies from 90 patients who underwent D2 radical gastrectomy to find out if there was any cancer cells attached to them. Highest numbers of cancer cells were found on gauze used to clean the surgical instruments and on the gloves of scrub nurses. The likelihood of finding cancer cells increased with advancing clinical stage of disease, lower differentiation of cancer cells, increasing frequency of use of supplies and extent of contact, and was also associated with the characteristic of surgical supplies. Dissemination of tumor cells could be prevented by using a number of methods, depending on the type of surgical supply items.