High Risk Of Peritoneal Recurrence Research Articles

Feasibility and Safety of Laparoscopic D2 Gastrectomy in Combination with Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in Patients with Gastric Cancer at High Risk of Recurrence-The PIPAC-OPC4 Study.

Patients with gastric adenocarcinoma (GAC) are at high risk of peritoneal recurrence despite perioperative chemotherapy and radical resection. This study evaluated feasibility and safety of laparoscopic D2 gastrectomy in combination with pressurized intraperitoneal aerosol chemotherapy (PIPAC). This was a prospective, controlled bi-institutional study in patients with GAC at high risk of recurrence treated with PIPAC with cisplatin and doxorubicin (PIPAC C/D) after laparoscopic D2 gastrectomy. High risk was defined as a poorly cohesive subtype with predominance of signet-ring cells, clinical stage ≥ T3 and/or ≥ N2, or positive peritoneal cytology. Peritoneal lavage fluid was collected before and after resection. Cisplatin (10.5 mg/m2) and doxorubicin (2.1 mg/m2) were aerosolized after anastomosis (flow 0.5-0.8 ml/s, maximum pressure 300 PSI). Treatment was feasible and safe if ≤ 20% had Dindo-Clavien ≥ 3b surgical complications or CTCAE ≥ 4 medical adverse events within 30 days. Secondary outcomes were length of stay (LOS), peritoneal lavage cytology, and completion of postoperative systemic chemotherapy. Twenty-one patients were treated with a D2 gastrectomy and PIPAC C/D. The median age was 61 years (range 24-76), there were eleven female patients, and 20 patients had preoperative chemotherapy. There was no mortality. Two patients had grade 3b complications that were potentially related to PIPAC C/D (one anastomotic leakage, and one late duodenal blow-out). One patient had severe neutropenia, and nine patients had moderate pain. The LOS was 6 days (4-26). One patient had positive peritoneal lavage cytology before resection, and none were positive after. Fifteen patients had postoperative chemotherapy. Laparoscopic D2 gastrectomy in combination with PIPAC C/D is feasible and safe.

Hyperthermic intraperitoneal chemotherapy (HIPEC) as adjuvant and therapeutic options for patients with advanced gastric cancer at high risk of recurrence or established peritoneal metastases: a single-centre experience.

Peritoneal metastases from gastric cancer (PM-GC) have a detrimental prognostic impact on survival and there is a lack of consensus regarding treatment. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) may offer a chance for prolonged survival as compared to standard chemotherapy. This study aims to present our experience in the management of GC with CRS and HIPEC. This is a single-centre retrospective study. Patients were divided into two groups: patients with GC at high risk for developing PM-GC (adjuvant HIPEC group) and patients with PM-GC or positive peritoneal cytology (therapeutic CRS and HIPEC group). Overall survival (OS) and disease-free survival (DFS) were considered as outcome measures. A total of 41 patients with a GC primary received surgery and HIPEC: 14 patients (34.1%) were in the adjuvant HIPEC group, while 27 patients (65.9%) were in the therapeutic CRS and HIPEC group. In the adjuvant HIPEC group, the 1- and 3-year OS were 85.7% and 71.4%, while 1- and 3-year DFS were 71.4% and 64.3%, respectively. In the therapeutic CRS and HIPEC group, OS was 60.3% and 35.1% at 1 and 3 years, whereas 1- and 3-year DFS were 38% and 32.6%, respectively. Univariate survival analysis of patients in the therapeutic CRS and HIPEC group showed that the presence of lymph node metastasis and signet ring cell histology predicted worse OS, while PCI > 12 and lymph node metastasis were associated with decreased DFS. Treatment of highly selected patients with GC at high risk of peritoneal recurrence or established PM with CRS and HIPEC showed satisfactory results in terms of OS and DFS.

Predicting peritoneal recurrence and disease-free survival from CT images in gastric cancer with multitask deep learning: a retrospective study

Peritoneal recurrence is the predominant pattern of relapse after curative-intent surgery for gastric cancer and portends a dismal prognosis. Accurate individualised prediction of peritoneal recurrence is crucial to identify patients who might benefit from intensive treatment. We aimed to develop predictive models for peritoneal recurrence and prognosis in gastric cancer. In this retrospective multi-institution study of 2320 patients, we developed a multitask deep learning model for the simultaneous prediction of peritoneal recurrence and disease-free survival using preoperative CT images. Patients in the training cohort (n=510) and the internal validation cohort (n=767) were recruited from Southern Medical University, Guangzhou, China. Patients in the external validation cohort (n=1043) were recruited from Sun Yat-sen University Cancer Center, Guangzhou, China. We evaluated the prognostic accuracy of the model as well as its association with chemotherapy response. Furthermore, we assessed whether the model could improve the ability of clinicians to predict peritoneal recurrence. The deep learning model had a consistently high accuracy in predicting peritoneal recurrence in the training cohort (area under the receiver operating characteristic curve [AUC] 0·857; 95% CI 0·826-0·889), internal validation cohort (0·856; 0·829-0·882), and external validation cohort (0·843; 0·819-0·866). When informed by the artificial intelligence (AI) model, the sensitivity and inter-rater agreement of oncologists for predicting peritoneal recurrence was improved. The model was able to predict disease-free survival in the training cohort (C-index 0·654; 95% CI 0·616-0·691), internal validation cohort (0·668; 0·643-0·693), and external validation cohort (0·610; 0·583-0·636). In multivariable analysis, the model predicted peritoneal recurrence and disease-free survival independently of clinicopathological variables (p<0·0001 for all). For patients with a predicted high risk of peritoneal recurrence and low survival, adjuvant chemotherapy was associated with improved disease-free survival in both stage II disease (hazard ratio [HR] 0·543 [95% CI 0·362-0·815]; p=0·003) and stage III disease (0·531 [0·432-0·652]; p<0·0001). By contrast, chemotherapy had no impact on disease-free survival for patients with a predicted low risk of peritoneal recurrence and high survival. For the remaining patients, the benefit of chemotherapy depended on stage: only those with stage III disease derived benefit from chemotherapy (HR 0·637 [95% CI 0·484-0·838]; p=0·001). The deep learning model could allow accurate prediction of peritoneal recurrence and survival in patients with gastric cancer. Prospective studies are required to test the clinical utility of this model in guiding personalised treatment in combination with clinicopathological criteria. None.

Regional therapy trials in peritoneal metastases: The path to standardization of care for gastric cancer.

As the peritoneum is the most common site of metastatic disease at diagnosis, disease identified at staging laparoscopy, and site of recurrence for patients with gastric cancer, intraperitoneal therapy has been an area of interest for many investigators. There are several ways to categorize the existing trials and studies. One is by indication, which includes palliative, neoadjuvant, adjuvant, and prophylactic. Another is by treatment modality which includes approaches such as hyperthermic intraperitoneal chemotherapy, pressurized intraperitoneal aerosol chemotherapy, intraperitoneal normothermic chemotherapy, and bidirectional combinations of systemic and intraperitoneal therapy. Recently completed and ongoing trials of peritoneal therapy in gastric cancer may be improving on the historically dismal survival rates for patients with carcinomatosis or disease at high risk of peritoneal recurrence. All completed randomized trials are from outside the United States, and additional studies of peritoneal therapy in Western populations are needed to clarify survival outcomes. Cooperative group trials and multi-institutional registry study efforts are ongoing to help address this clear area of unmet need.

Clinical significance of coexisting histological diffuse type in stage II/III gastric cancer.

Since 1965, the Laurén classification has been used most commonly for gastric adenocarcinoma, with two main types: intestinal type and diffuse type. Signet ring cell carcinoma (Sig) and non-solid poorly differentiated adenocarcinoma (Por2) are the histological forms of diffuse type that are often found in advanced tumors, and they seem to be associated with a poor prognosis. S-1-based adjuvant chemotherapy for patients with stage II/III gastric cancer has generally been accepted in Japan, but histological type does not alter treatment strategy. The aim of the present study was to investigate the prognostic impact of the histopathological mixture of Sig and Por2 in patients with stage II/III gastric cancer treated with S-1 adjuvant chemotherapy. The clinicopathological data of 968 patients with gastric carcinoma who underwent gastrectomy between 2007 and 2016 at Osaka City University Hospital were retrospectively analyzed. In the present study, tumors containing Sig or Por2 were classified as diffuse type, and those not containing them were classified as intestinal type. There were 307 cases of diffuse type and 661 cases of intestinal type. Diffuse type included 189 cases with Sig. A pathological diagnosis of Sig was an independent risk factor for peritoneal recurrence in patients with stage II/III gastric cancer. Patients with diffuse type had a worse overall survival rate than those with intestinal type at stage III gastric cancer. Among the patients who received S-1 adjuvant chemotherapy, the prognosis of patients with stage III gastric cancer with Sig but not Por2 was significantly worse compared with that of patients with intestinal type. Therefore, the present study revealed that the coexistence of Sig in the primary tumor was associated with a poor prognosis in patients with stage III gastric cancer. The current findings suggested that, since mixed Sig gastric cancer had a high risk of peritoneal recurrence even if adjuvant chemotherapy was performed, the pathological diagnosis should be considered when determining the therapeutic strategy for adjuvant chemotherapy in patients with stage III gastric cancer.

Study protocol of a multicenter phase III randomized controlled trial investigating the efficiency of the combination of neoadjuvant chemotherapy (NAC) and neoadjuvant laparoscopic intraperitoneal hyperthermic chemotherapy (NLHIPEC) followed by R0 gastrectomy with intraoperative HIPEC for advanced gastric cancer (AGC): dragon II trial

BackgroundEven though treatment modalities such as adjuvant systemic radio-chemotherapy and neoadjuvant chemotherapy (NAC) have individually have improved overall survival (OS) and progression-free survival (PFS) rates in advanced Gastric Cancer (AGC), the peritoneum still presides as a common site of treatment failure and disease recurrence. The role of hyperthermic intraperitoneal chemotherapy (HIPEC) has been acknowledged as prophylaxis for peritoneal carcinomatosis (PC) in AGC patients and in this study, we aim at investigating the safety and efficacy of the combination of neoadjuvant laparoscopic HIPEC (NLHIPEC) with NAC in the neoadjuvant phase followed by surgery of curative intent with intraoperative HIPEC followed by adjuvant chemotherapy (AC).MethodsIn this multicenter Phase III randomized controlled trial, 326 patients will be randomly separated into 2 groups into a 1:1 ratio after laparoscopic exploration. The experiment arm will receive the proposed comprehensive Dragon II regimen while the control group will undergo standard R0 D2 followed by 8 cycles of AC with oxaliplatin with S-1 (SOX) regimen. The Dragon II regimen comprises of 1 cycle of NLHIPEC for 60mins at 43 ± 0.5 °C with 80 mg/m2 of Paclitaxel followed by 3 cycles of NAC with SOX regimen and after assessment, standard R0 D2 gastrectomy with intraoperative HIPEC followed by 5 cycles of SOX regimen chemotherapy. The end-points for the study are 5 year PFS, 5 year OS, peritoneal metastasis rate (PMR) and morbidity rate.DiscussionThis study is one of the first to combine NLHIPEC with NAC in the preoperative phase which is speculated to provide local management of occult peritoneal carcinomatosis or peritoneal free cancer cells while NAC will promote tumor downsizing and down-staging. The addition of the intraoperative HIPEC is speculated to manage dissemination due to surgical trauma. Where the roles of intraoperative HIPEC and NAC have individually been investigated, this study provides innovative insight on a more comprehensive approach to management of AGC at high risk of peritoneal recurrence. It is expected that the combination of NLHIPEC with NAC and HIPEC will increase PFS by 15% and decrease PMR after gastrectomy of curative intent.Trial registrationWorld Health Organization Clinical Trials - International Registry Platform (WHO-ICTRP) with Registration ID ChiCTR1900024552, Registered Prospectively on the 16th July, 2019.

Peritoneal Carcinomatosis of Gastric Origin - Treatment Possibilities.

Peritoneal carcinomatosis of gastric origin is challenging to diagnose and treat. This disease is often misdiagnosed in the early stages using a non-invasive technique. Conventional surgery is unsuitable for treatment of patients with peritoneal seeding and positive peritoneal cytology. Peritoneal recurrence is the most frequent cause of therapeutic failure. The effectiveness of chemotherapy is low due to the plasma-peritoneal barrier. Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is the standard treatment for pseudomyxoma peritonei and mesothelioma and improves overall survival and disease-free survival. This approach is also widely used to prevent and treat peritoneal carcinomatosis of gastric origin. This article aims to provide a short summary of the contemporary role of cytoreductive surgery and HIPEC for treatment of gastric cancer patients. Theoretically, there are four possible applications and indications. First, palliative application to improve quality of life without prolongation of overall survival. This application mainly affects malignant ascites. Second, therapeutic application using a combination of gastrectomy/cytoreductive surgery and HIPEC to treat advanced disease including peritoneal metastases. Localized peritoneal seeding is the only indication for this application (maximum peritoneal cancer index of 10-12 or Cy+). Third, adjuvant/prophylactic application in patients at high risk of peritoneal recurrence, typically those with T3, T4, N+ disease (without peritoneal seeding). Fourth, neoadjuvant application using a combination of repeated HIPEC and chemotherapy with the aim of decreasing peritoneal seeding and enabling radical surgery. In this indication, HIPEC is often replaced by pressurized intraperitoneal aerosol chemotherapy.

Mesothelin Expression Is a Predictive Factor for Peritoneal Recurrence in Curatively Resected Stage III Gastric Cancer.

Mesothelin is overexpressed in many solid tumors, and recent studies have shown that mesothelin expression is associated with poor outcomes in several malignant tumors and may play a role in cancer progression. Clinical trials of mesothelin-targeted immunotherapies are currently under way, but the correlation between mesothelin expression and gastric cancer prognosis is still unclear. Mesothelin expression in tumor cells was evaluated immunohistochemically in 958 patients with advanced gastric cancer and interpreted according to the intensity and extent of staining. Samples were scored from 0 to 2, with high expression defined as a score of 2. Clinicopathological factors, overall survival (OS), recurrence-free survival (RFS), and sites of initial recurrence, including peritoneal recurrence, were evaluated. Staging was performed according to the American Joint Committee on Cancer 7th edition. High mesothelin expression was observed in 49.7% of patients and significantly associated with high pathologic T (p = .021) and peritoneal recurrence (p = .018). Multivariate survival analysis showed that high mesothelin expression was independently associated with poor RFS (p = .001), OS (p = .001), and peritoneal recurrence (p = .002) in addition to stage, lymphovascular invasion, and Lauren classification. In a subgroup analysis of peritoneal recurrence, high mesothelin expression was also an independent prognostic factor in stage III (p = .013) and diffuse/mixed type gastric cancer (p = .010). High mesothelin expression is correlated with poor outcomes. In addition, mesothelin expression, Lauren classification, and stage are meaningful predictive factors for peritoneal recurrence. Moreover, mesothelin was a significant predictor of a high risk of peritoneal recurrence in patients with stage III gastric cancer. This study demonstrates that high mesothelin expression correlates with poor outcomes and is a significant predictor of peritoneal recurrence in patients with stage III gastric cancer. This study provides instrumental evidence for designing anti-mesothelin antibody-drug conjugate clinical trials in patients with diffuse-type gastric cancer to reduce their high risk of peritoneal carcinomatosis.

Surgical treatment of peritoneal metastases of colorectal cancer

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) may significantly improve overall survival in selected patients with peritoneal metastases of colorectal cancer. For good oncological results complete macroscopic cytoreduction is crucial; furthermore, alinear correlation between peritoneal tumor load, as determined by the peritoneal cancer index (PCI) and overall survival has been demonstrated; therefore, surgical treatment should be initiated as early as possible. Synchronous resection of up to three liver metastases may be performed safely and with good results and no influence on the morbidity. With respect to intraperitoneal chemotherapy, mitomycinC and oxaliplatin are most commonly used and may be regarded as equal; however, for perioperative chemotherapy study results are so far inconclusive with some trials hinting at decreased overall survival following neoadjuvant chemotherapy. Adjuvant therapy is likely to improve overall survival if at least 6cycles are applied. Early detection of peritoneal metastases is difficult at present but might be facilitated in the future by the use of liquid biopsies, which may detect circulating free tumor-specific DNA or RNA. In the meantime, planned second-look laparotomy should be considered for patients at high risk of peritoneal recurrence. In addition, several international studies are currently evaluating the concept of adjuvant or prophylactic HIPEC. The CRS and HIPEC may be repeated in cases of recurrence and should be considered in suitable patients, applying the same criteria as for primary CRS and HIPEC. Arecurrence-free interval of >2years is associated with asignificantly better prognosis.

HIPECT4: multicentre, randomized clinical trial to evaluate safety and efficacy of Hyperthermic intra-peritoneal chemotherapy (HIPEC) with Mitomycin C used during surgery for treatment of locally advanced colorectal carcinoma

BackgroundLocal relapse and peritoneal carcinomatosis (PC) for pT4 colon cancer is estimated in 15,6% and 36,7% for 12 months and 36 months from surgical resection respectively, achieving a 5 years overall survival of 6%. There are promising results using prophylactic HIPEC in this group of patients, and it is estimated that up to 26% of all T4 colon cancer could benefit from this treatment with a minimal morbidity. Adjuvant HIPEC is effective to avoid the possibility of peritoneal seeding after surgical resection. Taking into account these results and the cumulative experience in HIPEC use, we will lead a randomized controlled trial to determine the effectiveness and safety of adjuvant treatment with HIPEC vs. standard treatment in patients with colon cancer at high risk of peritoneal recurrence (pT4).Methods/DesignThe aim of this study is to determine the effectiveness and safety of adjuvant HIPEC in preventing the development of PC in patients with colon cancer with a high risk of peritoneal recurrence (cT4). This study will be carried out in 15 Spanish HIPEC centres. Eligible for inclusion are patients who underwent curative resection for cT4NxM0 stage colon cancer. After resection of the primary tumour, 200 patients will be randomized to adjuvant HIPEC followed by routine adjuvant systemic chemotherapy in the experimental arm, or to systemic chemotherapy only in the control arm. Adjuvant HIPEC will be performed simultaneously after the primary resection. Mitomycin C will be used as chemotherapeutic agent, for 60 min at 42–43 °C. Primary endpoint is loco-regional control (LC) in months and the rate of loco-regional control (%LC) at 12 months and 36 months after resection.DiscussionWe assumed that adjuvant HIPEC will reduce the expected absolute risk of peritoneal recurrence from 36% to 18% at 36 months for T4 colon-rectal carcinoma.Trial registrationNCT02614534 (clinicaltrial.gov) Nov-2015.

Examination of cancer cells exposed to gastric serosa by serosal stamp cytology plus RT-PCR is useful for the identification of gastric cancer patients at high risk of peritoneal recurrence

BackgroundWe sought to clarify the clinical value of the examination of cancer cells exposed to gastric serosa by our novel method of serosal stamp cytology and a real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis. MethodA total of 70 patients who underwent gastrectomy were enrolled. Stamp cytology specimens were obtained by stamping the gastric serosa at the primary gastric tumor lesion, followed by Papanicolaou's staining. Samples obtained by brushing the serosa at the primary gastric tumor were analyzed by our RT-PCR of carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20). ResultsAmong the 70 patients, 11 patients were diagnosed as stamp cytology-positive. Eight and five patients were found to be CEA-positive and CK20-positive, respectively. Since 21 of the 70 patients were either stamp cytology-positive or RT-PCR analysis-positive, these 21 patients were considered to be positive for cancer cells exposed to serosa of primary gastric tumor. The 3-year recurrence-free survival rate of the patients with a single positive result by our method (41.7%) was significantly (log rank p = 0.0002) worse than that of the patients with both negative results (81.0%). Our method showed 58.8% sensitivity and 79.2% specificity. A multivariate analysis revealed that a stamp cytology and/or RT-PCR result was an independent prognostic factor for recurrence. ConclusionThe examination of cancer cells exposed to gastric serosa by our serosal stamp cytology and RT-PCR system will be useful for the identification of patients at high risk for peritoneal recurrence after curative surgery for gastric cancer.

Locally advanced colorectal cancer: Is a second look surgery and prophylactic HIPEC warranted?

e15056 Background: Peritoneal recurrence/carcinomatosis (PC) after curative surgery for colorectal cancer is the second most common site of recurrence and carries a poor prognosis. PC present relatively in the later stage, are difficult to detect by conventional imaging on follow up, and have limited options to treat after diagnosis. Second look surgery is the only definite option to diagnose early PC and presents an opportunity for disease control by cytoreductive surgery (CRS) and HIPEC. Multiple studies have attempted to identify clinico-pathological risk factors that predict high chances of PC. Our aim is to analyze the recurrence patterns and survival in locally advanced colorectal cancer, in an attempt to identify high risk factors for PC, which can be used as an indication for second look surgery and prophylactic HIPEC in such cases. Methods: Retrospective analysis of a prospectively maintained data of all colorectal cancer patients presenting to a tertiary cancer care referral center in India, from May 2010 to October 2015 was done. All patients who underwent surgery with curative intent and were clinico-pathological stage T4 and/or N2 M0 were included in the analysis. Results: 182 patients underwent curative resection with a clinico-pathological staging of T4 and/or N2 M0. There were 71 recurrences, out of which 30 (42.2%) were peritoneal, 7 (9.9%) were hepatic only while 34 (47.9 %) were non-hepatic systemic or multiple site. For a median follow up of 26 months, the estimated 3 year OS was 78 % while the 3 year DFS was 50.4 %. The median time to diagnosis of peritoneal recurrence was 13 months (4.7 – 55.7). The 3-year OS for patients with peritoneal recurrence was 48.6 % as against 57 % for liver only recurrence and 59.9 % for non liver systemic and multiple site recurrence, with a trend towards poorer survival for peritoneal recurrences, although non-significant (p – 0.377). Conclusions: Locally advanced colorectal cancer has a high risk of peritoneal recurrence which negatively impacts the survival. Well-designed RCTs need to be conducted to identify the high risk factors for PC and whether second look surgery and prophylactic HIPEC in such patients will improve survival with acceptable morbidity and mortality.

Strategies to prevent peritoneal carcinomatosis arising from colorectal cancer.

In the last decades, cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy became a curative option for peritoneal metastases in selected patients, otherwise considered for palliative therapy alone. Better knowledge of physiopathology of peritoneal spread and identification of predictive factors for peritoneal relapse prompted specialized centers to investigate the role of a 'proactive approach' in order to early detect peritoneal metastasis. These encouraging data could justify an active attitude in selected patients at high risk of peritoneal recurrence after curative resection of primary tumor. Selection criteria and the timing of complementary hyperthermic intraperitoneal chemotherapy remain important points of discussion. In this article, we will discuss treatment principles and future perspectives to early treat and, if possible, to prevent peritoneal dissemination after curative treatment of colorectal cancer.

Regional but fatal: Intraperitoneal metastasis in gastric cancer.

Peritoneal carcinomatosis appears to be the most common pattern of metastasis or recurrence and is associated with poor prognosis in gastric cancer patients. Many efforts have been made to improve the survival in patients with peritoneal metastasis. Hyperthermic intraperitoneal chemotherapy remains a widely accepted strategy in the treatment of peritoneal dissemination. Several phase II-III studies confirmed that the combined cytoreducitve surgery and hyperthermic intraperitoneal chemotherapy resulted in longer survival in patients with peritoneal carcinomatosis. In addition, proper selection and effective regional treatment in patients with high risk of peritoneal recurrence after resection will further improve prognosis in local advanced gastric cancer patients.

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.

Macroscopic Serosal Classification Predicts Peritoneal Recurrence for Patients with Gastric Cancer Underwent Potentially Curative Surgery

Previous studies revealed serosal invasion as one of the most important predictors of peritoneal micrometastasis. However, even for cancers with serosal invasion, the macroscopic serosal appearance is highly heterogeneous. The aim of the present study was to propose a macroscopic serosal classification (MSC) and to investigate the validity of this classification as a predictor of peritoneal recurrence. Clinicopathologic features including MSC of 1528 patients with pT3/pT4a stage gastric cancers who underwent potentially radical surgery were retrospectively reviewed. MSC was classified as reactive type, nodular type, tendonoid type, and color-diffused type according to the macroscopic serosal appearance. There were significant differences in tumor size, location, Bormann type, Lauren grade, lymphatic and/or blood vessels invasion (LBVI), width of serosa changes, depth of invasion, number of nodes metastasis, lymph node metastasis ratio, pN stage, and peritoneal cytology between patients with different types of serosa. Multivariate analysis revealed MSC, as well as depth of invasion, Lauren grade, and pN stage, significantly predicted the presence of peritoneal-free cancer cells. Both MSC and peritoneal cytology significantly correlated with patient survival. However, only MSC significantly predicted peritoneal recurrence on multivariate analysis, but peritoneal cytology did not, indicating MSC was more sensitive than cytologic examination. Further investigation suggested MSC and pN stage were also independent predictors of peritoneal recurrence for patients with negative peritoneal cytology. The MSC sensitively predicts the presence of peritoneal micrometastasis for pT3/pT4a-stage gastric cancer patients who underwent potentially radical surgery. Consequently, it might be considered a good indicator to guide perioperative adjuvant therapy for patients with high risk of peritoneal recurrence.

Intraoperative, adjuvant treatment of gastric cancer with the trifunctional antibody catumaxomab compared to surgery alone: A phase II study

15529 Background: Gastric cancer patients (pts) have a high risk of peritoneal recurrence due to disseminated tumor cells after surgery. The trifunctional antibody catumaxomab (anti-EpCAM × anti-CD3) administered locally into the peritoneal cavity aims at residual tumor cells while activating a complex anti-tumor immune reaction. Methods: A total of 55 gastric cancer pts (T2b/T3/T4, N±, M0) were randomized during surgical D2 procedure to surgery alone or catumaxomab administered as one intraoperative intraperitoneal (ip) and 4 postoperative ip infusions with ascending doses on day 7, 10, 13 and 16. Primary objectives were safety, tolerability and feasibility. Results: All 55 pts (27 surgery alone, 28 catumaxomab) were included in the safety analysis. The target antigen EpCAM was confirmed in 100 % of pts. 78 % (22/28) of the patients treated with catumaxomab received all 5 infusions. 40 % of the treatment-emergent adverse events (TEAEs) occurred directly after the intraoperative administration. TEAEs (CTC-grade ≥3) occurred in 22 patients (control arm: 10 patients). The most frequently TEAEs in the catumaxomab group were anemia, pyrexia, SIRS and abdominal pain. All related serious TEAEs resolved until end of treatment except for nephropathy (one patient), which resolved with minor sequelae. No trend of an accumulation of severe adverse reactions or complications (e.g. wound healing) occurred compared to the surgery only group. Conclusions: Adjuvant treatment of ip administration of catumaxomab is safe and well-tolerable in pts after curative resection, the safety results reflecting catumaxomab´s mode of action (cytokine release related symptoms). This offers a new chance to avoid intraabdominal tumor recurrence. First clinically relevant efficacy data will be obtained after the 1- and 2-year follow-up period. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Expert Testimony Other Remuneration Fresenius Biotech GmbH Fresenius Biotech GmbH Fresenius Biotech GmbH Fresenius Biotech GmbH

Prospective study of the quantitative carcinoembryonic antigen and cytokeratin 20 mRNA detection in peritoneal washes to predict peritoneal recurrence in gastric carcinoma patients

The prediction of peritoneal recurrence in gastric cancer patients is extremely important in preventing an unfavorable prognosis. In this prospective study, we examined the usefulness of the carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20) mRNA detection in peritoneal washes as a prophylactic tool for peritoneal recurrence. Peritoneal washes were obtained from 164 patients with gastric carcinoma during a laparotomy. CEA, CK20 and glyceraldehyde-3-phosphate-dehydrogenase mRNA levels in the peritoneal washes were detected by real-time reverse transcription-polymerase chain reaction (RT-PCR) using LightCycler. Molecular detection of the CEA and CK20 mRNA in the peritoneal washes by real-time RT-PCR showed a significant correlation with tumor size, histological type, depth of invasion, lymphatic invasion, venous invasion, lymph node metastasis, peritoneal dissemination, stage and cytology. The peritoneal recurrence-free survival and overall survival rates of CEA and CK20 mRNA-positive patients were significantly worse than those of marker gene-negative patients. The CEA and CK20 mRNA levels in the peritoneal washes were a significant independent prognostic factor. In conclusion, our prospective study demonstrates that the detection of CEA and CK20 mRNA by quantitative real-time RT-PCR is a useful tool for identifying patients at high risk of peritoneal recurrence who may need adjuvant chemotherapy.

Prospective study of peritoneal recurrence after curative surgery for gastric cancer.

Peritoneal carcinomatosis is a common cause of failure after surgery for gastric cancer. The present longitudinal study was designed to evaluate the incidence and potential predictors of peritoneal recurrence after curative resection for gastric cancer. Four hundred and forty-one patients who underwent potentially curative resections for gastric cancer in three surgical centres between 1988 and 1996 were evaluated. All patients were followed using a standard protocol following discharge from hospital. The correlation between tumour recurrence and clinicopathological variables was studied by univariate and multivariate analyses. Gastric cancer recurred in 215 (49 per cent) of 441 patients. Peritoneal recurrence was observed in 77 patients (17 per cent), locoregional recurrence in 96 patients and haematogenous recurrence in 75. Multivariate logistic regression analysis of factors associated with peritoneal recurrence identified diffuse-mixed histological type (relative risk (RR) 4.31, P < 0.001), infiltration of the serosa (RR 3.36, P = 0.001), lymph node involvement (RR 2.67, P = 0.023) and tumour size (RR 1.11, P = 0.050) as significant independent variables. In the diffuse-mixed histological subtype, the 5-year cumulative risk of peritoneal recurrence was 12 per cent in the absence of serosal invasion, and 69 per cent in patients with infiltration of the serosa; in the intestinal subtype, the cumulative risk in patients with serosa-negative and -positive tumours was 4 and 21 per cent respectively. Radical surgery offers a low probability of cure in patients with diffuse-mixed type of gastric cancer and involvement of the serosa, due to a high risk of peritoneal recurrence. These patients might benefit from adjuvant therapies to prevent peritoneal carcinomatosis.

Implications of peritoneal washing cytology in patients with potentially resectable pancreatic cancer.

The aim of this study was to assess the implications of positive peritoneal washing cytology for management of patients with potentially resectable pancreatic cancer. Cytological examination of peritoneal washings was performed in 134 patients who underwent surgical resection for pancreatic adenocarcinoma. The clinicopathological findings and the relationship between cytology results (including cytomorphology) and survival were investigated. One hundred and fourteen patients (85 per cent) had negative cytology results (group 1). Excluding one patient with atypical cells, positive cytology results were obtained in 19 patients (14 per cent): 16 patients without macroscopic peritoneal metastases (group 2) and three patients with minimal macroscopic peritoneal metastases (group 3). The patients in group 2 had significantly larger (P < 0.001) and more advanced (P = 0.022) tumours than those in group 1. However, there were no significant differences in postoperative cumulative survival rates between groups 1 and 2 (P = 0.347). Two patients in group 2 are long-term survivors (40 and 58 months). In cytomorphological analyses, the presence of clusters with ragged edges and isolated carcinoma cells can be considered to indicate a high risk of peritoneal recurrence. Positive cytology does not directly predict peritoneal carcinomatosis and, while associated with advanced disease, does not contraindicate radical surgery.