Cytoreductive surgery for synchronous and metachronous colorectal peritoneal dissemination: Japanese P classification and peritoneal cancer index

Aim

The outcomes of cytoreductive surgery (CRS) for synchronous and metachronous colorectal peritoneal dissemination were investigated using the Japanese P classification and peritoneal cancer index (PCI).

Methods

CRS was performed in 111 cases of synchronous peritoneal dissemination and 115 cases of metachronous peritoneal dissemination. The P classification and PCI were determined at the time of laparotomy.

Results

In the synchronous dissemination group, the 5-year overall survival rates after CRS in P1/P2 and P3 cases were 51% and 13%, respectively. Even for P3, 51% of the patients achieved macroscopic cytoreductive complete resection (CC-0), with a 5-year survival rate of 40%. When P3 cases were classified into PCI 0-9, 10-19, 20-29, and 30-39, CC-0 was achieved in 93%, 70%, 6%, and 0% of the cases, respectively, and the 5-year survival rate of PCI 0-9 was 41%. In the metachronous dissemination group, the 5-year survival rates were 62% for PCI 0-9 and 22% for PCI 10-19; 5-year survival was not observed in patients with a PCI ≥ 20. CC-0 was significantly associated with the postoperative prognosis in both synchronous and metachronous peritoneal dissemination.

Conclusion

In cases of synchronous dissemination, CRS must be performed for P1 and P2 cases or those with a PCI < 10, while detailed examination using PCI is required for P3 cases. In cases of metachronous dissemination, CRS should be considered when the PCI score is <20.

Analysis of the characteristics and outcomes of patients with pseudomyxoma peritonei of appendiceal origin treated with curative-intent surgery

BACKGROUND

There are no previous studies on pseudomyxoma peritonei regarding the details of surgical procedures included in cytoreductive surgery and quantitative evaluation for peritoneal metastases by region in the abdominal cavity. This study aimed to describe the characteristics and procedural details involved in cytoreductive surgery, and survival outcomes of patients with pseudomyxoma peritonei originating from appendiceal mucinous neoplasm, and identify differences in the difficulty of cytoreductive surgery based on tumor location.

METHODS

Patient characteristics and survival outcomes were studied through a retrospective review. The complete cytoreduction rate (i), the 5-year survival rate for patients with complete cytoreduction (ii), and an index as a complement (i × ii × 100) were described for patients who had tumors larger than 50 mm in one of the 13 regions of the abdominal cavity.

RESULTS

A total of 989 patients were treated with curative-intent cytoreductive surgery. The median peritoneal cancer index was 18 (interquartile range, 6-29), with complete cytoreduction achieved in 702 patients (71%); the major complication rate was 17%. The median overall survival was 92.9 months, compared to 53.8 months for patients who underwent total gastrectomy and 30.4 months for those who underwent total colectomy. In the 13 abdominal regions, the index scores indicating cytoreduction difficulty were categorized into three risk groups: upper and mid-abdominal (>20), lateral abdominal (10-20), and small bowel (<10).

CONCLUSIONS

Cytoreductive surgery offered favorable survival outcomes, even in cases involving total gastrectomy. The difficulty of achieving complete cytoreduction varied across abdominal regions and was classified into three levels.

[Pseudomyxoma Peritonei Caused by Intraductal Papillary Mucinous Neoplasm-A Three Case Series]

Pseudomyxoma peritonei(PMP)is a rare condition caused by intraductal papillary mucinous neoplasm(IPMN). At our institution, 3 cases, along with literature review, of PMP caused by IPMN were treated with cytoreductive surgery. In case 1, a 70-year-old man was pathologically diagnosed with low-grade PMP with intraductal papillary mucinous carcinoma. Recurrence was discovered 68 months after surgery, and the patient died after 78 months. In case 2, a 69-year-old man was pathologically diagnosed with high-grade PMP with signet-ring cell carcinoma caused by intraductal papillary mucinous carcinoma. The patient died 8 months post-surgery. In case 3, a 77-year-old woman was pathologically diagnosed with low- grade(partially high-grade)PMP with intraductal papillary mucinous adenoma. There was a recurrence 14 months post- surgery. The patient is still alive because of systemic chemotherapy 32 months after surgery.

A rare case of pseudomyxoma peritonei with Morgagni hernia

Both pseudomyxoma peritonei and Morgagni hernias in adults are rare clinical conditions. A 70-year-old woman who was diagnosed with pseudomyxoma peritonei with Morgagni hernia underwent cytoreductive surgery and primary repair. Pseudomyxoma peritonei causes increased intra-abdominal pressure that may lead to acquired congenital diaphragmatic hernia when there is a local fragility in the diaphragmatic musculature. Parietal peritonectomy of the right diaphragmatic peritoneum can safely remove the hernia sac. The high rate of infections associated with cytoreductive surgery causes hesitation for concurrent mesh repair for Morgagni hernia. This is the first report of pseudomyxoma peritonei with Morgagni hernia. Cytoreductive surgery including parietal peritonectomy of the right diaphragmatic peritoneum plus primary repair of hernial defect was performed safely and successfully, which achieved positive short-term results for patients with pseudomyxoma peritonei-associated Morgagni hernia.

Rationale of Treatment for Peritoneal Metastasis

In 1998, the Peritoneal Surface Oncology Group International(PSOGI)proposed a novel treatment referred to as comprehensive treatment(COMPT). COMPT involves the complete removal of macroscopic tumors(cytoreductive surgery: CRS) and eradication of micrometastasis(MM)with neoadjuvant chemotherapy(NAC)plus intraoperative hyperthermic intraperitoneal chemotherapy(HIPEC). This article provides a rationale for curative COMPT. Additionally, based on our experience, the selection criteria for treatment will be clarified.

RATIONALE

The residual cancer cell burden is lowest immediately following CRS, and intraoperative HIPEC plays a crucial role in the treatment of patients with peritoneal surface malignancy (PSM). COMPT will fail if the number of the MM remaining after CRS exceeds the limit of complete eradication by intraoperative HIPEC(threshold). However, if the residual number of MM is less than the threshold, patients will respond positively to treatment.

PATIENTS AND METHODS

To validate the direct effect of HIPEC, laparoscopic HIPEC(LHIPEC)was performed, and changes in the peritoneal cancer index(PCI)were then evaluated. Complete cytoreduction and HIPEC carried out based on the concept of COMPT was performed in 171 gastric cancer(GC)patients with PCI≤12, 183 colorectal cancer(CRC)with PCI≤21 and 460 pseudomyxoma peritonei(PMP)patients with PCI≤28. The postoperative survivals rates were then analyzed.

RESULTS

After 1 cycle of LHIPEC, PCIs in GC and PMP were significantly reduced by 1.85 and 2.7 1 month after LHIPEC. However, PCI of CRC increased. Positive cytology at LHIPEC became negative in 57.6%, 42.9% and 60.9% of patients with GC, CRC and PMP, respectively. Median survival time(MST)for GC and CRC was 21.2 and 71.5 months, respectively MST of PMP was not reached. MST of PMP was not reached. Ten-year survival rates were 12.6%, 21.7% and 81.6%, respectively. Grade 5 complications for each disease were 0.8%, 1.0% and 1.1%, respectively.

CONCLUSIONS

Complete cytoreductive surgery combined with intraoperative HIPEC may improve the long-term survival of patients with PSM who have PCIs less than the threshold levels, by keeping the mortality rates after CRS plus intraoperative HIPEC within acceptable levels.

Effect of oxaliplatin-based chemotherapy on chemosensitivity in patients with peritoneal metastasis from colorectal cancer treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: proof-of-concept study

Background

Chemosensitivity testing, including collagen gel droplet‐embedded culture drug sensitivity test, has proven to be a useful tool in therapeutic decision‐making. This retrospective analysis investigated chemosensitivity testing of peritoneal metastases collected during cytoreductive surgery (CRS), and its impact on survival in patients with colorectal cancer.

Methods

All patients with peritoneal metastasis from colorectal cancer who underwent CRS with or without hyperthermic intraperitoneal chemotherapy (HIPEC) between November 2008 and October 2014 were included. The growth inhibition rate was expressed as the ratio between the image density after treatment (T) and that before treatment (control, C). Tumours with a reduction in T/C ratio of less than 20 per cent were defined as resistant and those with a reduction of 20 per cent or more as sensitive. Groups were compared for overall (OS) and disease‐free (DFS) survival.

Results

Of 84 eligible patients, 81 received neoadjuvant chemotherapy (NACT), including 56 patients with an oxaliplatin‐based regimen. Mean(s.d.) follow‐up was 23·4(22·9) months. The median overall survival of all patients was 19·0 (i.q.r. 5·7–36·1) months, with a progression‐free survival time of 10·1 (4·5–17·0) months. Patients who received oxaliplatin‐based NACT had significantly altered chemosensitivity to oxaliplatin; only 20 of 51 such patients showed chemosensitivity to oxaliplatin compared with 16 of 24 who did not undergo oxaliplatin‐based NACT (P = 0·046). However, patients who showed chemoresistance to oxaliplatin had similar OS to those with chemosensitivity (18·8 versus 18·1 months; P = 0·835). The choice of HIPEC agents in patients who received oxaliplatin‐based NACT did not significantly influence survival (oxaliplatin versus mitomycin C: median OS 20·6 (10·9–24·8) versus 19·0 (10·5–34·6) months, P = 0·811; DFS 6·6 (2·8–25·7) versus 9·3 (4·1–13·9) months, P = 0·191).

Conclusion

Patients who had oxaliplatin‐based NACT showed a higher rate of chemoresistance to oxaliplatin at the time of CRS and HIPEC. The impact of chemosensitivity testing on OS remains unclear and needs further investigation.

Thirty-three long-term survivors after cytoreductive surgery in patients with peritoneal metastases from colorectal cancer: a retrospective descriptive study

BACKGROUND

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival in selected patients with peritoneal metastasis (PM) from colorectal cancer (CRC). However, little has been reported on characteristics and clinical course of long-term survivors with CRC-PM beyond 5 years. The objective of this study was to identify the clinical and oncological features affecting long-term survival of CRC-PM after comprehensive treatment.

METHODS

Between January 1990 and April 2015, CRC-PM patients who underwent CRS with or without HIPEC in two Japanese tertiary hospitals were analyzed. Clinicopathological parameters and therapeutic details for long-term survivors (patients surviving ≥ 5 years after CRS) were described and compared with those for non-survivors (patients surviving < 5 years).

RESULTS

The study identified 236 patients with CRC-PM who underwent CRS, with a median follow-up period of 2.5 years. Thirty-three patients (14.0%) were considered as long-term survivors. Compared with non-survivors, long-term survivors had a lower median peritoneal cancer index (PCI) [4 (1-27) vs 9 (0-39), p < 0.001]. Complete cytoreduction (CCR-0) was achieved in all long-term survivors, with a significantly higher rate [33/33 (100%) vs 141/203 (69.8%), p < 0.001]. Metachronous onsets of PM were more frequently observed in the long-term survivor group [26/33 (78.8%) vs 103/203 (50.3%), p = 0.018]. Regarding histopathology, long-term survivors more frequently had mucinous adenocarcinoma than non-survivors [8/33 (24.2%) vs 27/203 (13.3%)] and less likely exhibited poorly differentiated or signet ring cell carcinoma [2/33 (6.1%) vs 48/203 (23.7%)] (p < 0.001).

CONCLUSIONS

One in seven patients with CRC-PM achieved the long-term milestone after CRS. A long-term survival was associated with the presence of low PCI, CCR-0, metachronous onset, and mucinous histology.

Retrospective Analysis of Patients with Signet Ring Subtype of Colorectal Cancer with Peritoneal Metastasis Treated with CRS & HIPEC

Simple Summary

Approximately 1% of all patients with colorectal cancer, and 15% of patients with peritoneal metastasized colorectal cancer present with the subtype of signet ring cell, which is associated with inferior oncological outcome and reduced overall survival. The evidence whether patients with signet ring cell subtype are benefiting from cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is limited. The aim of this large bicentric retrospective study including 60 patients with this subtype was to explore the survival and define predictive factors of these patients. Median overall survival was 14.4 months, while small bowel PCI > 2 (HR: 6.5; p = 0.008) was the strongest predictive factor for inferior patient survival. The study concludes, that after thoroughly selection patients for CRS and HIPEC, even patients with signet ring cell subtype of colorectal cancer may benefit from this concept.

Abstract

Signet ring cell subtype (SRC) of colorectal cancer (CRC) is a rare subtype and occurs in approximately 1% of all patients with CRC. Patients with peritoneal metastasis (PM) of SRC have a poor prognosis, and this subtype is frequently considered as a contra-indication for extensive surgical treatment. This retrospective study from two dedicated peritoneal surface malignancy centers in Japan included all patients treated with CRS ± hyperthermic intraperitoneal chemotherapy (HIPEC) between July 1994 and December 2017 from a prospectively maintained database. Preoperative, operative, and postoperative parameters were recorded, including complication rates and follow-up. Sixty of the 320 patients treated with CRS due to CRC were diagnosed with SRC subtype. The mean age of the patients was 51.4 years, and the mean peritoneal carcinomatosis index (PCI) was 13.1. Complete cytoreduction was achieved in 61.7% of cases. The postoperative morbidity rate was 25% and the mortality rate was 1.7%. The median overall survival (OS) was 14.4 months. Cox regression analysis revealed small bowel PCI > 2 (hazard ratio (HR) 6.5; p = 0.008) as the most important factor for OS. With accurate patient selection (e.g., PCI ≤ 12 or small bowel PCI ≤ 2), even patients with PM of CRC with SRC subtype may benefit from CRS and HIPEC, with median OS from 17.8 to 20.8 months and 5-year OS of 11.6%.

Advances with pharmacotherapy for peritoneal metastasis

INTRODUCTION

A new treatment strategy involving cytoreductive surgery (CRS) combined with perioperative intraperitoneal (IP) chemotherapy was proposed in 1999 by the Peritoneal Surface Oncology Group International, and the strategy is now justified as a state-of-the-art treatment to improve the long-term survival of patients with peritoneal metastasis (PM). To achieve cure in the patients with PM, complete removal of macroscopic tumors and eradication of micrometastasis on the peritoneum, left after CRS are essential. Systemic chemotherapy is not indicated for the treatment of PM. In contrast, intraperitoneal (IP) chemotherapy brings about significantly higher locoregional dose intensity in the peritoneal cavity and subperitoneal tissues. In combination with anticancer drugs, hyperthermia enhances cytotoxicity against cancer cells.

AREA COVERED

This article provides a systematic overview of PM from various cancers including gastric, colorectal, small bowel, appendiceal cancer, and mesothelioma. It also includes all the essential aspects of therapy.

EXPERT OPINION

CRS plus perioperative intraperitoneal chemotherapy is safe with acceptable morbidity and mortality. It is justified as a standard treatment to improve the long-term survival of patients with PM and is now performed with curative intent for PM from various malignancies.

P1742 Occurrence of right ventricle dysfunction in patients with Brugada syndrome: a follow-up study by echocardiography and electrophysiological examination

Background

Brugada syndrome (BrS) has been characterized by no apparent structural abnormalities in both ventricles, but, recently, the presence of subtle right ventricular (RV) structural abnormalities in patients with BrS has been reported.

Purpose

The aim of this study was to evaluate the occurrence of RV dysfunction in patients with BrS and their characteristics.

Methods

We enrolled 49 consecutive patients (54 ± 11 years old) diagnosed with Brs and underwent echocardiography from 2017 to 2018. The echocardiographic parameters and electrophysiological examinations were evaluated including RV size and function such as RV outflow and inflow tract diameter, TAPSE, S’, and FAC. Abnormality threshold for parameters of RV dysfunction is defined as followed: a TAPSE of &lt;17 mm, an S’ of &lt;9.5 cm, and an FAC of &lt;35%.

Results

Among 49 patients, one patient showed a TAPSE of &lt;17 mm, 5 patients an S’ of &lt;9.5 cm, and 10 patients an FAC of &lt;35%. Evaluating characteristics of Brs patients with RV dysfunction, all patients were divided into 2 groups by the value of RV FAC; 39 patients showing FAC &gt;35% (group A), 10 patients FAC ≤35% (group B). The comparison of each parameter between 2 groups is shown in Table. TAPSE and S’ in group B were lower than in group A. RV inflow tract diameter in group B was larger than in group A, although there was no differences in RV out tract diameter. There were no significant differences in left ventricular parameters, and grade of tricuspid regurgitation. QRS duration prolonged and the rate of ICD implantation was higher in group B than in group A. Moreover, all patients in group B showed RV wall motion abnormalities and the distribution was as followed: diffuse (n = 2), RV mid (n = 2), RV apex (n = 6).

Conclusions

BrS patients frequently showed RV dysfunction during follow-up, and it may be related to the prolongation of QRS duration. We should pay much attention to the occurrence of RV dysfunction in follow-up echocardiography.

Group A (FAC &gt;35%) N = 39 Group B (FAC ≤35%) N = 10 p-value TAPSE, mm 22.9 ± 2.1 20.4 ± 2.6 0.009 S", cm/s 12.8 ± 2.0 11.1 ± 1.4 0.010 RV outflow tract, mm 29.7 ± 4.4 31.2 ± 5.0 0.49 RV mid inflow tract, mm 30.4 ± 2.9 33.8 ± 3.7 0.008 RV basal inflow tract, mm 38.5 ± 3.2 43.7 ± 4.0 0.001 QRS duration, ms 112.9 ± 12.9 136.3 ± 28.4 0.006 Late potential positive, n (%) 25 (64) 8 (80) 0.34 ICD implantation, n (%) 19 (68) 9 (90) 0.019

Effects of Cytoreductive Surgery Combined with Perioperative Chemotherapy on Long-Term Survivals of Colorectal Cancer Patients with Peritoneal Metastasis, with Special Reference to the Involved Peritoneal Sectors and Organs

Peritoneal Surface Oncology Group International(PSOGI)proposed a novel treatment, named comprehensive treatment for peritoneal metastasis(PM)from colorectal cancer(CRC). The present study demonstrated the efficacies of the treatment regarding the peritoneal sectors and organs involved with PM from CRC.

MATERIALS AND METHODS

Among 365 patients received laparotomy, 278 CRC patients with PM underwent complete cytoreductive surgery(CC-0).

RESULTS

After CC-0 resection Grade 3, Grade 4, and Grade 5 postoperative complication were found in 20(7.2%), 26(9.3%), and 6(2.2%). Five- and 10-year survival rate(YSR)of CC-0 resection were 24.5%, and 11.6% with median survival time(MST)of 42.0 months. Regarding the peritoneal cancer index(PCI)of small bowel(SB-PCI), all patients of PCI B3 died of the disease. In contrast, 10-YSR of patients with SB-PCI of 0, 1, and 2 were 26.1%, 19.5%, and 6.2%, respectively. Ten-YSR of patients with the number of involved peritoneal sectors C9 ranged from 6.9% to 29.8%. MST of patients with PM in each peritoneal sector(sector 0 to sector 8)ranged from 26.4 months to 49.2 months, and 10-YSR ranged from 4.2%to 17.2%. Ten-YSR of patients with involvement of rectum, stomach, liver capsule, seminal vesicle, ureter, uterus, or ovary ranged from 0% to 16.9%.

CONCLUSIONS

From the present data, PM should be removed aggressively to achieve complete cytoreduction, when the patients with PCIC26, involved peritoneal sectorsC9 and SB-PCIC2 are supposed to receive complete cytoreduction of PM.

Hyperthermic intraperitoneal chemotherapy in management of malignant intraductal papillary mucinous neoplasm with peritoneal dissemination: Case report

•

IPMN is not a common disease, has low risk to develop invasive lesion. But when invasion occurred, the prognosis is poor.

•

Malignant IPMN with peritoneal dissemination also has poor prognosis.

•

CRS and HIPEC can prolong survival in malignant IPMN with peritoneal dissemination patient.

•

Pseudomyxoma peritonei can be found as rare manifestation of IPMN, that can associate with tumor rupture form diagnostic procedure like EUS-FNA or surgical procedure.

Introduction

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are treatment to deal with peritoneal dissemination that has excellent result for various cancer especially pseudomyxoma peritonei (PMP), mesothelioma. For now, this combination of treatment is still running for pancreatic adenocarcinoma but no description for pancreatic cystic tumor like malignant Intraductal papillary mucinous neoplasm (IPMN).

Presentation of cases

We report 3 cases of malignant IPMN with peritoneal dissemination that treated with CRS and HIPEC. Two cases have atypical presentation of malignant IPMN with PMP. HIPEC was performed using cisplatin-based regimen. The longest survival in this study is 93 months, compared to the median survival of 44.3 months without HIPEC.

Discussion

CRS and HIPEC have not proven to treat in patient with pancreatic cystic tumor with peritoneal dissemination. But these treatments can be improved survival outcome in selected patient.

Conclusion

CRS and HIPEC trend to improve survival. More studies need, not only to evaluate the role of HIPEC on malignant IPMN, but also prognosis and outcome.

Prognostic significance of the presence of epithelial cell clusters in the ascites of patients with pseudomyxoma peritonei

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare condition characterized by intraperitoneal accumulation of mucus due to mucinous neoplasia. The characteristic cytological feature of PMP in the ascites is abundant mucus with or without epithelial cell clusters. However, the prognostic significance of the presence of epithelial cell clusters has not been determined. This study aimed to determine the prognostic significance of epithelial cell clusters in the ascites of patients with PMP.

METHODS

Patients who were clinically and histopathologically diagnosed with PMP and who underwent intraoperative cytological examination of their ascites were included in this study. Cytological characteristics including mucus and epithelial cell clusters, nuclear atypia, and the presence of signet ring cells were investigated. Overall survival was compared based on the presence of epithelial cell clusters or nuclear atypia.

RESULTS

A total of 283 patients (199 women and 84 men) were investigated. The most common original site was the appendix (244 patients). Ninety patients (31.8%) had mucus without epithelial cell clusters (acellular mucin) while 193 (68.2%) had mucus with such clusters; 134 (69.4%) and 44 (22.8%) of these patients showed low-grade and high-grade nuclear features, respectively. Signet ring cells were detected in 15 patients (7.8%). The presence of epithelial cell clusters did not influence overall survival (P = .28); however, high-grade nuclear features and signet ring cell presence were significant negative prognostic factors (P < .001).

CONCLUSION

The presence of high-grade nuclear features or of signet ring cells should be carefully investigated in the cytological specimens of patients with PMP.

Analysis of Treatment Failure after Complete Cytoreductive Surgery for Peritoneal Metastasis from Appendiceal Mucinous Neoplasm at a Japanese High Volume Center for Peritoneal Surface Malignancy

BACKGROUND AND OBJECTIVES

Treatment failure after complete cytoreduction for appendiceal mucinous carcinoma peritonei (AMCP)has not been fully investigated. The present study was performed to clarify the risk factor for recurrence after complete cytoreduction for AMCP.

METHODS

A total of 400 patients with AMCP who underwent complete cytoreductive surgery combined with perioperative chemotherapy were investigated.

RESULTS

Documented recurrence was developed in 135 (33.8%)patients. The 5- and 10-year progression-free survival was 51% and 49%, respectively. By multivariate analysis, histological subtype of peritoneal disease(high-grade AMCP[AMCP-H]and AMCP-H with signet ring cells), serum CA19- 9 level, and PCIB20 were significantly associated with reduced progression-free survival. In contrast, histologic subtype of mucin without epithelial cells(MWEC)showed the lowest risk for recurrence. Eighty-six patients had localized intra-abdominal recurrence, and 42 patients had diffuse peritoneal recurrence. Recurrence was found in the various peritoneal sectors. Eighty-one patients underwent complete cytoreduction for the recurrence, and the overall survival 5-year survival rate after secondary cytoreduction was 49%.

CONCLUSIONS

Risk factors for recurrence were histologic subtype, PCI cutoff level, and serum CA19-9 levels. Aggressive second attempt of cytoreduction in patients with localized recurrence improved the survival.

History of Peritoneal Surface Malignancy Treatment in Japan

In this review, Japanese experience of cytoreductive surgery and perioperative chemotherapy is described. The new concept of peritoneal metastasis (PM) type, i.e., trans-mesothelial, trans-lymphatic, and superficial growing metastasis type was proposed in 2012. Surgeons should perform peritonectomy according to the type of PM. Since 1980, Japanese surgical oncologists have been spearheading the use of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemoperfusion (HIPEC) as treatment for PM from gastric cancer. Two RCTs were conducted to verify the effect of HIPEC for the prophylaxis of peritoneal recurrence after curative resection of advanced gastric cancer. These two studies indicated that HIPEC is effective in preventing peritoneal recurrence of gastric cancer with serosal invasion. In 2002, intraperitoneal chemotherapy using taxans was developed for the treatment of PM from gastric cancer and led to the development of neoadjuvant intraperitoneal/systemic chemotherapy (NIPS), which was reported in 2006. In 2009, extensive intra-operative peritoneal lavage (EIPL) was developed, and contributed to the remarkable improvement in survival of patients with positive lavage cytology as demonstrated by prospective randomized clinical trials. In 2017, the Peritoneal Surface Oncology Group International proposed the value of complete cytoreduction and peritoneal cancer index cut-off as independent prognostic factors after CRS for gastric cancer with PM. Founded in 2016, the Japanese/Asian School of Peritoneal Surface Oncology (JASPSO) trains beginners to perform CRS and HIPEC safely. Sixteen students have already graduated from JASPSO and started to perform the treatment in their home countries.

Prognostic Factors of Malignant Peritoneal Mesothelioma Experienced in Japanese Peritoneal Metastasis Center

BACKGROUND AND OBJECTIVES

The current standard of treatment for malignant peritoneal mesothelioma(MPM)is cytoreductive surgery(CRS)plus perioperative intraperitoneal or systemic chemotherapy(comprehensive treatment), The present study was performed to clarify the prognostic factors of PMP after comprehensive treatment.

METHODS

Among 63 patients with MPM, male and female patients were 34 and 29. CRSwas performed in 47 patients and complete cytoreduction(CC-0) was performed in 14(22%)patients. Mean numbers of resected peritoneal sectors and organs were 5.2(1-13), and 2.9(0- 9), respectively. Hyperthermic intraperitoneal chemoperfusion(HIPEC)was performed in 27 patients. Grade 1/2, Grade 3, and Grade 4 complications were experienced in 5, 6, and 3 patients, respectively. One patient died of sepsis, and the mortality rate was 2.3%. Independent prognostic factors for favorable prognosis were performance of HIPEC, peritoneal cancer index (PCI)score C12, no distant metastasis and histologic epithelial type. Relative risk of no HIPEC, PCI score B13, presence of distant metastasis and non epithelial type were 7.69, 22.1, 3.6 and 3.9, respectively.

CONCLUSIONS

Risk factors for death after comprehensive treatment were no HIPEC, PCI score B13, and non epithelial type. However, only 11(17%)patients showed PCI score C12. Accordingly, PCI score should be reducedC12 before CRSby neoadjuvant chemotherapy.

Comprehensive Treatment Using Cytoreductive Surgery Combined with Perioperative Chemotherapy Improved Outcome of Colorectal Cancer Patients with Metachronous Peritoneal Metastasis

To analyze the role of cytoreductive surgery(CRS)plus perioperative chemotherapy on the survival of colorectal cancer(CRC)patients with metachronous peritoneal metastasis(PM). A comprehensive treatment consisting of neoadjuvant chemotherapy plus CRS was performed in 291 CRC patients. Among the 291, 142 and 149 patients had synchronous and metachronous PM, respectively. The results showed no survival difference between the 2 groups. Median survival time(MST)of patients with metachronous PM with complete cytoreduction(CCR-0), small bowel(SB)-PCIC2, PCIC14 and differentiated histologic type ranged from 3.1 to 4.1 years. Five-year survival rates of metachronous group of the CCR-0, SB-PCIC2, PCI C14 and differentiated histologic type ranged from 25.8 to 38.9%. However, the 5-year survival rates of the incomplete cytoreduction(CCR-1), SB-PCIB3, PCIB15 and poorly differentiated type were significantly lower than those of the CCR-0, SB-PCIC2, PCIC14 and differentiated histologic type. Postoperative Grade 3, and Grade 4 morbidity were experienced in 11(5.8%)and 16(10.7%)in metachronous group. Mortalities of metachronous group were 1.3%(2/149). The comprehensive treatment can be performed safely and improves the survival of CRC patients with metachronous PM. After NAC, patients with SB-PCIC2, PCIC14 and differentiated type of histology are candidates for CRS, and CCR-0 resection combined with HIPEC is recommended.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for appendiceal goblet cell carcinomas with peritoneal carcinomatosis: results from a single specialized center

Background

Goblet cell carcinomas (GCCs) of the appendix are rare and aggressive malignancies with early peritoneal dissemination. The aim of the present article is to describe our experience in the management of GCCs with peritoneal carcinomatosis (PC) through cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) and to determine the impact of multiple clinical characteristics on the prognosis.

Methods

From a prospectively maintained database of patients receiving CRS and HIPEC for peritoneal surface malignancy, the data of 15 patients with GCC and PC were collected. Neo-adjuvant laparoscopic HIPEC was performed if indicated. CRS and HIPEC with mitomycin-C or 5-fluorouracil plus oxaliplatin were performed. Adjuvant chemotherapy was also arranged if suitable for the patient’s condition.

Results

Nine males and six females with a mean age of 52.4 years were enrolled. The estimated median survival after the diagnosis of GCC with PC and after definitive CRS–HIPEC was 28 and 17 months, respectively. The 1-, 2-, 3-, 4-year survival rates were 86%, 69%, 57%, and 24%, respectively. Log-rank test revealed that the significant independent risk factors for more favorable outcomes were age >50 years, peritoneal cancer index (PCI) <27, postoperative PCI <20, administration of HIPEC, and adjuvant chemotherapy. Multivariate analyses confirmed that administration of HIPEC played a crucial role in providing prognostic benefit.

Conclusion

The management of GCC with PC remains challenging. We recommend CRS and HIPEC, followed by adjuvant systemic chemotherapy, as a promising strategy to improve survival, especially in selected patients with low PCI and possibility to achieve complete cytoreduction.

A case of ovarian growing teratoma syndrome treated by cytoreductive surgery

Ovarian growing teratoma syndrome (GTS) is a rare disease characterized by growth of a benign tumor during or after chemotherapy, following the removal of germ cell gonadal cancers. Although benign, GTS tumors grow gradually and may compress surrounding organs. In addition, up to 3% of GTS cases can undergo malignant transformation. It is, therefore, needed to treat GTS. No standardized management protocol has been established to treat GTS; however, surgical resection is likely the only effective treatment because tumors in GTS are resistant to chemotherapy and radiation therapy. However, complete resection with conventional procedures is sometimes difficult when peritoneal metastasis is widespread. We report a rare case of ovarian GTS with widespread peritoneal metastases, which was totally resected by peritonectomy procedures. A 45-year-old Japanese woman was initially diagnosed with an immature teratoma grade 3, which was treated by hysterectomy and bilateral salpingo-oophorectomy. Adjuvant chemotherapy was performed after surgery with bleomycin, etoposide, cisplatin, and other chemotherapies. Due to recurrence of a chemoresistant tumor and normalization of tumor markers, GTS was suspected. She was referred to our institute, and complete cytoreductive surgery was performed using peritonectomy procedures, including parietal peritoneal resection, greater omentectomy, lesser omentectomy, rectosigmoid colectomy, diaphragm dissection, and cholecystectomy. A complete cytoreduction with no visible residual tumor tissue was achieved.

Photodynamic Detection of Peritoneal Metastases Using 5-Aminolevulinic Acid (ALA)

In the past, peritoneal metastasis (PM) was considered as a terminal stage of cancer. From the early 1990s, however, a new comprehensive treatment consisting of cytoreductive surgery and perioperative chemotherapy has been established to improve long-term survival for selected patients with PM. Among prognostic indicators after the treatment, completeness of cytoreduction is the most independent predictors of survival. However, peritoneal recurrence is a main cause of recurrence, even after complete cytoreduction. As a cause of peritoneal recurrence, small PM may be overlooked at the time of cytoreductive surgery (CRS), therefore, development of a new method to detect small PM is desired. Recently, photodynamic diagnosis (PDD) was developed for detection of PM. The objectives of this review were to evaluate whether PDD using 5-aminolevulinic acid (ALA) could improve detection of small PM.

Treatment Failure Following Complete Cytoreductive Surgery for Peritoneal Metastasis from Colorectal Cancer

Treatment failure after complete cytoreduction for peritoneal metastasis(PM)from colorectal cancer(CRC)has not been fully investigated. The present study was performed to clarify the risk factors for recurrence after complete cytoreduction for CRC with PM and the role of repeat surgery for recurrence.

MATERIALS AND METHODS

A total of 205 patients with CRC who underwent complete cytoreductive surgery combined with perioperative chemotherapy were investigated.

RESULTS

Recurrence occurred in 149(73%)patients. The 5-year overall and progression-free survival rates were 26%and 7%, respectively. By multivariate analysis, positive cytology, serum CEA level higher than normal range, and small bowel peritoneal cancer index B3 were significantly associated with reduced progression-free survival. Blood-borne recurrence was found in 62 (44%)of 149 patients. Repeat surgery was performed in 44(30%), and complete removal was performed in 28(64%) patients. Long-term survival after repeat surgery was experienced in patients with localized peritoneal recurrence and/or liver recurrence.

CONCLUSIONS

This study showed that a second attempt at cytoreduction in patients with localized intra-abdominal and liver recurrence is of benefit. Blood-borne recurrence was found in 44% of recurrent patients. The prophylaxis of recurrence should therefore be performed using systemic chemotherapy after CRS plus HIPEC.

Effects of Neoadjuvant Laparoscopic Hyperthermic Intraperitoneal Chemotherapy and Neoadjuvant Intraperitoneal/Systemic Chemotherapy on Peritoneal Metastases from Gastric Cancer

BACKGROUND

The Peritoneal Cancer Index (PCI) is the most important prognostic factor following comprehensive treatment for peritoneal metastasis (PM) from gastric cancer (GCPM); however, 70 % of patients with GCPM showed a PCI score above the cut-off level at the time of diagnosis. Furthermore, neoadjuvant chemotherapy may reduce the PCI score to lower than the cut-off levels. In this study, the effects of neoadjuvant laparoscopic hyperthermic intraperitoneal chemoperfusion (NLHIPEC) and neoadjuvant intraperitoneal/systemic chemotherapy (NIPS) were investigated.

MATERIALS AND METHODS

In group A, NLHIPEC was performed twice in 53 patients with GCPM, separated by a 1-month rest interval. Changes in the PCI were studied at the time of first and second laparoscopy. In group B, after NLHIPEC, a series of 3-week cycles of NIPS were performed over three courses in 52 patients. A laparotomy for cytoreductive surgery (CRS) was then carried out and the PCI changes were studied.

RESULTS

In group A, the PCI score at the time of the second session (11.8 ± 11.0) was significantly lower than at the time of the first session (14.2 ± 10.7), while in group B, the PCI at the time of laparotomy (9.9 ± 11.3) was significantly lower than at the time of NLHIPEC (14.8 ± 11.4). After NLHIPEC plus NIPS, complete cytoreduction was achieved in 30 (57.6 %) patients.

CONCLUSIONS

NLHIPEC and NIPS are effective methods of reducing PCI levels before CRS.

A comprehensive treatment for peritoneal metastases from gastric cancer with curative intent

Recently, Peritoneal Surface Oncology Group International (PSOGI) developed a novel comprehensive treatment consisting of cytoreductive surgery (CRS) and perioperative chemotherapy (POC) for the treatment of peritoneal metastases (PM) from gastric cancer with curative intent. This article reviews the results of this treatment and verifies its indication. In this strategy, peritoneal cancer index (PCI) is determined by laparoscopy, and a peritoneal port is placed. Neoadjuvant bidirectional intraperitoneal/systemic chemotherapy (NIPS) is performed for 3 cycles, and then laparotomy is performed. Cytoreductive surgery with peritonectomy procedures and hyperthermic intraperitoneal chemoperfusion (HIPEC) are performed. Multivariate analyses showed that completeness of cytoreduction, pathologic response to NIPS and PCI level and cytologic status after NIPS, as independent prognostic factors. PCI less than cut-off level after NIPS, negative cytology after NIPS, and positive response to NIPS were identified as the indications for comprehensive treatment. Patients who hold these criteria should be considered as the candidates for CRS and HIPEC.

Cytoreductive Surgery Plus Hyperthermic Intraperitoneal Chemotherapy for Pseudomyxoma Peritonei Arising from Urachus

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare locoregional disease characterized by disseminated intraperitoneal mucinous tumors. However, little is known about PMP from urachal neoplasm as a result of its rarity.

METHODS

A total of 9 patients with PMP of urachal origin were treated by cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in our institution. All specimens of surgeries were submitted for pathologic examination. Representative slides of tumors and normal urachus were submitted for immunohistochemical staining.

RESULTS

Four patients were men; the median age was 48 years (range 27-65 years). Initial radiologic examination of all patients showed a cystic tumor located between posterior aspect of umbilicus and the dome of urinary bladder, with or without leaking mucin. Complete CRS and HIPEC were performed in all patients. Until the latest follow-up, local recurrence occurred in 1 patient. Other 8 patients had a median disease-free survival of 27.5 months. Primary urachal tumors of 9 cases were all mucinous adenocarcinoma. Six patients had low-grade mucinous carcinoma peritonei, and 3 patients had high-grade mucinous carcinoma peritonei. Signet ring cells were noted in 4 patients. All tumor specimens of 9 patients were diffuse positive for CK-20, CDX-2, MUC-2, and MUC-5AC, and were variant positive for CK-7.

CONCLUSIONS

PMP arising from urachus comes from neoplastic cells with development of intestinal-type mucinous neoplasm. It shares a similar pathophysiology as PMP from appendix. CRS including total urethrectomy, partial cystectomy, and peritonectomy plus HIPEC can be considered as a new option of treatment for PMP originating from urachus.

Peritoneal cancer treatment

INTRODUCTION

In the past, peritoneal surface malignancy (PSM) was considered as a final stage of cancer, and patients were offered the best supportive care. Recently, a new therapeutic alternative approach based on the combination of surgery with chemotherapy was developed. In this curative intent, the macroscopic disease was treated with cytoreductive surgery (CRS) combined with perioperative chemotherapy, including neoadjuvant chemotherapy, hyperthermic intraoperative intraperitoneal chemotherapy, extensive intraoperative peritoneal lavage and early postoperative intraperitoneal chemotherapy

AREAS COVERED

This article reviews the mechanisms of the formation of PSM, quantitative estimation of PSM and residual disease, multimodal treatment, value of laparoscopy, prognostic factors and patients' selection for the multimodal therapy.

EXPERT OPINION

Recent studies show that CRS plus intraperitoneal chemotherapy applications confer prolonged survival in patients with PSM from colorectal, gastric, ovarian, appendiceal mucinous carcinoma and diffuse malignant peritoneal mesothelioma. The comprehensive treatment is now justified as state-of-the-art for patients with peritoneal metastasis.

Pharmacokinetics of docetaxel during hyperthermic intraperitoneal chemotherapy for peritoneal metastasis

The purpose of this manuscript is to report the pharmacokinetics of docetaxel during hyperthermic intraperitoneal chemotherapy (HIPEC) after peritonectomy.

MATERIALS AND METHODS

Eleven patients with peritoneal metastasis (PM) underwent peritonectomies combined with 40 min of HIPEC with 40 mg/body of docetaxel. The pharmacokinetics of docetaxel were studied by using high-performance liquid chromatography.

RESULTS

The docetaxel concentration at the start of HIPEC (0 min) was 9.084 ± 0.972 mg/L. The concentration gradually decreased to 5.599 ± 0.458 mg/L 40 min after HIPEC. In contrast, serum docetaxel levels increased during HIPEC, reaching a maximum level of 0.1334 ± 0.0726 mg/L at 40 min. The clearance (CLp) was 3.164 ± 1.383 L/hr, and the area under the curve (AUC) ratio was 95.12 ± 87.32. The AUC ratio of less-extensive peritonectomies was significantly higher than that of extended peritonectomies. The docetaxel concentration in the tumor tissue increased at 40 min (4.45 mg/gr). The apparent permeability (Papp, 40 min) was 1.47 ± 0.67 mm/40 min. No severe adverse effects were observed after HIPEC.

CONCLUSION

From these results, 40 mg is a safe dose for docetaxel combined with HIPEC, and the locoregional intensity of docetaxel is enough to control PM less than 1.47 mm in diameter.

[A case of gastric adenosquamous carcinoma with peritoneal dissemination in which treatment with S-1 plus paclitaxel therapy resulted in improved long-term survival]

Gastric adenosquamous carcinoma is a rare malignancy with a poor prognosis. We recently performed palliative gastrectomy for a gastric adenosquamous carcinoma with peritoneal dissemination and provided a course of systemic chemotherapy with S-1 plus paclitaxel(PTX)after the surgery. No serious adverse events were observed, and treatment with S-1 plus PTX was continued for 1 year before being switched to adjuvant chemotherapy with S-1 alone for another year. The tumor maker levels normalized within 2 months of the initial treatment, and the peritoneal dissemination could no longer be detected by abdominal computed tomography(CT). The patient remained in clinical remission and maintained long-term survival of over 8 years.

Outcome data of patients with peritoneal carcinomatosis from gastric origin treated by a strategy of bidirectional chemotherapy prior to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in a single specialized center in Japan

BACKGROUND

Management of peritoneal disseminated gastric cancer (GC) remains a challenging problem. The purpose of our study was to evaluate the outcome of bidirectional induction chemotherapy [bidirectional intraperitoneal and systemic induction chemotherapy (BIPSC)] in patients with peritoneal carcinomatosis (PC) arising from GC who underwent cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

PATIENTS AND METHODS

Overall, 194 patients with PC arising from GC were treated with BIPSC comprising intraperitoneal docetaxel at a dose of 20 mg/m(2) and cisplatin at a dose of 30 mg/m(2) followed by four cycles of oral S-1 at a dose of 60 mg/m(2). CRS and HIPEC were performed in responders to BIPSC.

RESULTS

Of these 194 patients, 152 (78.3 %) underwent CRS and HIPEC between January 2005 and December 2012. Treatment-related mortality was 3.9 %, and major complications occurred in 23.6 % of patients. The median survival rate was 15.8 months, with 1-, 2-, and 5-year survival rates of 66, 32 and 10.7 %, respectively, in the patients treated with combined treatment. Multivariate analysis identified pathologic response to BIPSC (p = 0.001), low tumor burden [peritoneal cancer index (PCI) ≤ 6] (p = 0.001), and completeness of CRS (CC-0, CC-1) (p = 0.001) as independent predictors for a better prognosis.

CONCLUSION

As a viable option, BIPSC with CRS and HIPEC for patients with PC arising from GC may be performed safely, with acceptable morbidity and mortality, in a specialized unit. Response to BIPSC, optimal CRS and limited peritoneal dissemination seem to be essential to achieve the best outcomes in these patients.

Effects of neoadjuvant intraperitoneal/systemic chemotherapy (bidirectional chemotherapy) for the treatment of patients with peritoneal metastasis from gastric cancer

Novel multidisciplinary treatment combined with neoadjuvant intraperitoneal-systemic chemotherapy protocol (NIPS) and peritonectomy was developed. Ninety-six patients were enrolled. Peritoneal wash cytology was performed before and after NIPS through a port system. Patients were treated with 60 mg/m(2) of oral S-1 for 21 days, followed by a 1-week rest. On days 1, 8, and 15, 30 mg/m(2) of Taxotere and 30 mg/m(2) of cisplatin with 500 mL of saline were introduced through the port. NIPS is done 2 cycles before surgery. Three weeks after NIPS, 82 patients were eligible to intend cytoreductive surgery (CRS) by gastrectomy + D2 dissection + periotnectomy to achieve complete cytoreduction. Sixty-eight patients showed positice cytology before NIPS, and the positive cytology results became negative in 47 (69%) patients after NIPS. Complete pathologic response on PC after NIPS was experienced in 30 (36.8%) patients. Stage migration was experienced in 12 patients (14.6%). Complete cytoreduction was achieved in 58 patients (70.7%). By the multivariate analysis, complete cytoreduction and pathologic response became a significantly good survival. However the high morbidity and mortality, stringent patient selection is important. The best indications of the therapy are patients with good pathologic response and PCI ≤ 6, which are supposed to be removed completely by peritonectomy.

Treatment results of peritonectomy combined with perioperative chemotherapy for colorectal cancer-patients with peritoneal carcinomatosis

Operation results of 81 colorecatal cancer-patients with peritoneal carcinomatosis (PC) treated with peritonectomy plus perioperative chemotherapy are reported. The patients who had the following evidences are considered to be eligible for peritonectomy: 1) No evidence of N3 lymph node involvement, 2) No evidence of hematogenous metastasis, 3) No progressive disease after preoperative chemotherapy, 4) No severe co-morbidities or no poor general condition. Complete cytoreduction resection is aimed for removing all macroscopic tumors by peritonectomy using electrosurgical techniques. The completeness of cytoreduction (CC scores) after peritonectomy is classified into the following 4 criteria: CC-0-no peritoneal seeding was exposed during the complete exploration, CC-1-residual tumor nodules are less than 2.5 mm in diameter, CC-2-nodules are between 2 .5 mm and 25 mm in diameter, CC-3-nodules are greater than 25 mm in diameter, CC-2 and CC-3 are regarded as incomplete cytoreduction. Operation time and blood loss were 237 ± 124 min. (799-90 min) and 1,598 ± 1,411 mL (6,500-20 mL), respectively. Postoperative complications developed in 37( 46%) patients. The patients received CC-0/ -1 resection survived significantly longer than those of CC-2/ -3 group. The patients with PCI ≤ 10 survived significantly longer than those with PCI≥ 11. CC and PCI scores are the independent prognostic factors. The relative risk for death of CC-2/-3 group was 4.6-fold higher than that of CC-0/ -1 group. Accordingly, peritonectomy is indicated for patients with PCI score≤ 10.

Diffusion-weighted magnetic resonance imaging for detecting lymph node metastasis of rectal cancer

BACKGROUND

Preoperative diagnosis of lymph node metastasis is important in determining the optimal therapy for rectal cancer. It has been shown that diffusion-weighted magnetic resonance imaging (DWI) is a useful tool for detecting malignant tumors.

METHODS

One hundred twenty-nine consecutive patients with rectal cancer were examined with DWI + conventional (T1-weighted and T2-weighted) MRI and computed tomography (CT). All 129 patients underwent rectal resection with total mesorectal excision. Findings on DWI + conventional MRI and CT were compared with those from histopathologic examinations.

RESULTS

Fifty-nine (46%) patients had metastatic lymph nodes on histopathologic examinations. Two hundred twenty (18%) of 1,250 lymph nodes were pathologically positive for tumor metastasis. The overall patient-based sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of DWI + conventional MRI were 93, 81, 81, 93, and 87%, respectively. Corresponding values of CT were 73, 79, 74, 77, and 76%, respectively. The overall node-based sensitivity, specificity, PPV, NPV, and accuracy of DWI + conventional MRI were 97, 81, 52, 99, and 84%, respectively. Corresponding values of CT were 86, 80, 48, 96, and 81%, respectively.

CONCLUSION

DWI + conventional MRI is effective for the detection of lymph node metastasis and useful for selection of the optimal therapy for rectal cancer.

Indication of peritonectomy for peritoneal dissemination

A total of 521 patients with peritoneal carcinomatosis (PC) were treated by peritonectomy and perioperative chemotherapy. Each of the 95, 58, 316, 31, 10 and 11 patients were from gastric, colorectal, appendiceal, ovarian, small bowel cancer and mesothelioma, respectively. The distribution and volume of PC are recorded by the Sugarbaker peritoneal carcinomatosis index (PCI). Peritonectomy was performed with a radical resection of the primary tumor and all gross PC with involved organs, peritoneum, or tissue that was deemed technically feasible and safe for the patient. The postoperative major complication of grade 3 was found in 14%, and total 30-day mortality was 2.7%. The survival of gastric cancer patients with a PCI score ≤ 6 was significantly better than those with a PCI score ≥ 7. In appendiceal neoplasm, patients with PCI score less than 28 showed significantly better survival than those with PCI score greater than 29. The survival of colorectal cancer patients with a PCI score ≥ 11 was significantly poorer than those with a PCI score ≤ 10. Among the various prognostic factors in appendiceal neoplasm and gastric cancer patients, CC-0 complete cytoreduction was the most important independent prognostic factor. Peritonectomy is done to remove macroscopic disease and perioperative intraperitoneal chemotherapy to eradicate microscopic residual disease aiming to remove disease completely with a single procedure. Peritonectomy combined with perioperative chemotherapy may achieve long-term survival in a selected group of patients with PC. The higher mortality rate underlines this necessarily strict selection that should be reserved to experienced institutions.

Multidisciplinary therapy for treatment of patients with peritoneal carcinomatosis from gastric cancer

There is no standard treatment for peritoneal carcinomatosis (PC) from gastric cancer. A novel multidisciplinary treatment combining bidirectional chemotherapy [neoadjuvant intraperitoneal-systemic chemotherapy protocol (NIPS)], peritonectomy, hyperthermic intraperitoneal chemoperfusion (HIPEC) and early postoperative intraperitoneal chemotherapy has been developed. In this article, we assess the indications, safety and efficacy of this treatment, review the relevant studies and introduce our experiences. The aims of NIPS are stage reduction, the eradication of peritoneal free cancer cells, and an increased incidence of complete cytoreduction (CC-0) for PC. A complete response after NIPS was obtained in 15 (50%) out of 30 patients with PC. Thus, a significantly high incidence of CC-0 can be obtained in patients with a peritoneal cancer index (PCI) ≤ 6. Using a multivariate analysis to examine the survival benefit, CC-0 and NIPS are identified as significant indicators of a good outcome. However, the high morbidity and mortality rates associated with peritonectomy and perioperative chemotherapy make stringent patient selection important. The best indications for multidisciplinary therapy are localized PC (PCI ≤ 6) from resectable gastric cancer that can be completely removed during a peritonectomy. NIPS and complete cytoreduction are essential treatment modalities for improving the survival of patients with PC from gastric cancer.

Multidisciplinary therapy for treatment of patients with peritoneal carcinomatosis from gastric cancer

There is no standard treatment for peritoneal carcinomatosis (PC) from gastric cancer. A novel multidisciplinary treatment combining bidirectional chemotherapy [neoadjuvant intraperitoneal-systemic chemotherapy protocol (NIPS)], peritonectomy, hyperthermic intraperitoneal chemoperfusion (HIPEC) and early postoperative intraperitoneal chemotherapy has been developed. In this article, we assess the indications, safety and efficacy of this treatment, review the relevant studies and introduce our experiences. The aims of NIPS are stage reduction, the eradication of peritoneal free cancer cells, and an increased incidence of complete cytoreduction (CC-0) for PC. A complete response after NIPS was obtained in 15 (50%) out of 30 patients with PC. Thus, a significantly high incidence of CC-0 can be obtained in patients with a peritoneal cancer index (PCI) ≤ 6. Using a multivariate analysis to examine the survival benefit, CC-0 and NIPS are identified as significant indicators of a good outcome. However, the high morbidity and mortality rates associated with peritonectomy and perioperative chemotherapy make stringent patient selection important. The best indications for multidisciplinary therapy are localized PC (PCI ≤ 6) from resectable gastric cancer that can be completely removed during a peritonectomy. NIPS and complete cytoreduction are essential treatment modalities for improving the survival of patients with PC from gastric cancer.

Multidisciplinary therapy for treatment of patients with peritoneal carcinomatosis from gastric cancer

There is no standard treatment for peritoneal carcinomatosis (PC) from gastric cancer. A novel multidisciplinary treatment combining bidirectional chemotherapy [neoadjuvant intraperitoneal-systemic chemotherapy protocol (NIPS)], peritonectomy, hyperthermic intraperitoneal chemoperfusion (HIPEC) and early postoperative intraperitoneal chemotherapy has been developed. In this article, we assess the indications, safety and efficacy of this treatment, review the relevant studies and introduce our experiences. The aims of NIPS are stage reduction, the eradication of peritoneal free cancer cells, and an increased incidence of complete cytoreduction (CC-0) for PC. A complete response after NIPS was obtained in 15 (50%) out of 30 patients with PC. Thus, a significantly high incidence of CC-0 can be obtained in patients with a peritoneal cancer index (PCI) ≤ 6. Using a multivariate analysis to examine the survival benefit, CC-0 and NIPS are identified as significant indicators of a good outcome. However, the high morbidity and mortality rates associated with peritonectomy and perioperative chemotherapy make stringent patient selection important. The best indications for multidisciplinary therapy are localized PC (PCI ≤ 6) from resectable gastric cancer that can be completely removed during a peritonectomy. NIPS and complete cytoreduction are essential treatment modalities for improving the survival of patients with PC from gastric cancer.

Safety and efficacy of bidirectional chemotherapy for treatment of patients with peritoneal dissemination from gastric cancer: Selection for cytoreductive surgery

There is no standard treatment for peritoneal carcinomatosis (PC) from gastric cancer. New bidirectional chemotherapy (neoadjuvant intraperitoneal-systemic chemotherapy protocol (NIPS)) was developed. The aim of the present study was to assess the safety and efficacy of NIPS and to show the selection for cytoreductive surgery on PC from gastric cancer. Seventy-nine patients with PC from gastric cancer were treated with NIPS. A peritoneal port system was introduced into the abdominal cavity. The peritoneal wash cytological examination through a port was done before and after NIPS. The patients were treated with oral TS-1 twice a daily for 21 days, followed by a 1-week rest. On day 1, 8, and 15 from the start of oral TS-1 administration, 30 mg/m(2) of Docetaxel and 30 mg/m(2) of cisplatinum with 500 ml of saline were introduced into the peritoneal cavity through the port. A median course of oral TS-1 was 2.1 course and a median time of IP chemoterapy was 5.8. Peritoneal free cancer cells (PFCCs) had been detected in 65 (82.2%) patients before NIPS, and the positive cytology changed to be negative in 41 (63.0%) patients after NIPS. After NIPS, 41 patients underwent laparotomy, and complete cytoreduction was done in 32 (78%) patients. Complete cytoreduction was done in 27 (51.9%) of 52 patients with negative cytology but in only 4 (14.8%) of 27 patients with positive cytology (P < 0.001). Patients with negative cytology after NIPS survived significantly longer than those with positive cytology. The adverse effects after NIPS were mild and there was no treatment-related deaths. The grade 3/4 hematological adverse effects were found in 2 (2.6%) patients. Grade 3 renal toxicity and port site infection was found in three patients, respectively. NIPS using a port system is a safe and effective treatment for PC. Peritoneal wash cytology through a port system is a good indicator to select the patients to perform cytoreductive surgery.

Relationship between intraduodenal 5-hydroxytryptamine release and interdigestive contractions in dogs

BACKGROUND

5-hydroxytryptamine (5-HT) is released into the intestinal lumen during the fasting state. However, the relationship between the intraduodenal 5-HT and the interdigestive cyclic motor activity in conscious dogs is unclear.

AIM

To correlate intraduodenal 5-HT concentrations with the interdigestive gastroduodenal migrating motor complex (MMC).

METHODS

6 dogs were implanted with 2 force transducers for recording gastroduodenal contractions and 2 catheters for measuring duodenal volume by a non-absorbable marker perfusion technique. Intraduodenal 5-HT concentrations were determined by high performance liquid chromatography at 5-min intervals.

RESULTS

During fasting, gastroduodenal motor activity cycled as the MMC; luminal 5-HT concentrations and total outputs varied cyclically in temporal association with the MMC. Mean 5-HT concentrations peaked during phase II (P<0.05 vs. phase I and III), and 5-HT outputs during phases II or III were greater than during phase I (P<0.05). Exogenous motilin (0.3 microg/kg-hr, IV) stimulated 5-HT release into the duodenal lumen with peak values (P<0.05) during motilin-induced phase II and III. Gastroduodenal motor activity was not altered, however, during exogenous intraduodenal administration of 5-HT (300 ng/mL-min).

CONCLUSIONS

5-HT is released cyclically into the duodenal lumen in close temporal association with the MMC, but its physiologic significance in regulation of gastroduodenal motility is unknown.

Effects of Nitric Oxide Synthase Inhibitor on the Digestive System Measured by Simultaneous Monitoring of Gastric Motility, Gastric Emptying Activity and Postprandial Pancreaticobiliary Secretion in Dogs

Relationships between the NO synthase inhibitor and gastric and pancreaticobiliary functions measured simultaneously in the digestive state have been little studied. The aim of this study was to estimate the effect of NO synthase inhibitor on integrated digestive function in conscious dogs. A strain gauge force transducer was implanted on the gastric antrum of 6 mongrel dogs to measure gastric contractile activity and two duodenal cannulas were inserted into the proximal and distal sites to measure the gastric emptying rate and the pancreaticobiliary output into the duodenum using our novel method. Postprandial pancreatic and biliary secretion were presented as amylase and bile acid activity, respectively. Furthermore, a cervical cannula was placed into the superior vena cava as a route for the administration of NO synthase inhibitor, N omega-nitro-L-arginine (L-NNA), at a dose of 2.5 mg/kg-h. In a group given L-NNA, gastric contractile activity after ingestion was significantly enhanced, but the emptying rates of gastric solids and liquids were significantly suppressed in comparison with the control. The mean 0-1 h amylase integrated output was significantly (P < 0.05) decreased in comparison with the control, and the mean bile acid integration of 0-1 h output was also significantly (P < 0.01) decreased. A possible explanation for this observation is that smaller volumes of nutrient are delivered into the duodenum; however, it could also be that postprandial pancreaticobiliary secretion is inhibited by an alteration of blood flow or by a change in contractions of the sphincter of Oddi after the administration of L-NNA.

Effect of motilin on endogenous release of insulin in conscious dogs in the fed state

The aim was to investigate the insulin-releasing activity of motilin during and after feeding. A single intravenous bolus injection of motilin (0.01-0.3 microg/kg) dose-dependently stimulated endogenous release of insulin in the postprandial state. The insulin-releasing activity of motilin in the fed state was completely abolished by pretreatment with atropine or hexamethonium and was partly inhibited by ondansetron. Truncal vagotomy also greatly suppressed the motilin-induced insulin release. While phentolamine significantly enhanced insulin release in response to motilin, propranolol significantly inhibited this response in both states. The motilin-induced insulin release in the fed states was not accompanied by any changes in glucose concentrations. In conclusion, while the physiological significance remains unclear, these results indicate that physiological doses of motilin stimulate endogenous release of insulin via a vagally cholinergic muscarinic pathway, and that adrenergic and 5-hydroxytryptamine3 receptors are also involved in this response, in the dog.

Calcium polycarbophil, a water absorbing polymer, increases bowel movement and prevents sennoside-induced diarrhea in dogs

The effects of calcium polycarbophil (CP), a water-absorbing polymer, on bowel movement were examined in comparison with known laxatives and anti-diarrheal agents in dogs, a species that resembles humans for stool output. CP increased stool frequency, fecal water content and fecal weight in a dose-dependent manner, but did not induce diarrhea. Sennoside and carboxymethylcellulose sodium (CMC-Na) increased fecal water content and induced diarrhea at lower doses than that which enhanced stool frequency. Trimebutine decreased stool frequency, fecal weight and fecal water content, resulting in inhibition rather than stimulation of defecation. In sennoside-induced diarrhea, loperamide and CP improved stool consistency and this was accompanied by reduced fecal moisture and frequency of diarrhea. In contrast, CMC-Na aggravated stool consistency with increased fecal water content and frequency of diarrhea, and trimebutine had little noticeable effect apart from reducing fecal weight. Our results show that CP has both laxative and anti-diarrheal effects in dogs and differed from conventional laxatives and anti-diarrheal agents. CP may be a suitable agent for treatment of idiopathic constipation, secretory diarrhea and irritable bowel syndrome with alternating constipation and diarrhea and with either predominating in terms of less side effects such as diarrhea or constipation.

Effect of truncal vagotomy on gallbladder bile kinetics in conscious dogs

Previous studies on the effects of vagotomy on gallbladder (GB) motility have yielded conflicting results. The aim of this study was to evaluate the effects of vagotomy on GB motility and bile kinetics using a new method. Twelve dogs were divided into two groups of six (control and pyloroplasty) and, 4 weeks later, underwent truncal vagotomy. A catheter secured in the GB fundus was used to monitor GB volume. After injecting polyethylene glycol (PEG) into the GB, combined measurements of GB volume and PEG concentration enabled GB emptying and bile kinetics to be estimated. Seven and five of the 12 vagotomized dogs were classified as having large and normal fasting GB volumes, respectively. Postprandial GB emptying was impaired when the fasting GB volume was enlarged. In the fasting state, bile kinetics of vagotomized dogs were significantly smaller than the control values. The emptying ability of the GB of vagotomized dogs with large fasting GB volumes was reduced considerably both in the postprandial and the fasting states. Such retention of bile in the GB after vagotomy may facilitate cholesterol crystal nucleation and stone growth.

Postprandial normal saline intake delays gastric emptying of solids in conscious dogs: partial involvement of CCK in its mechanism

Although it is known that a caloric liquid meal given after food intake delays solid gastric emptying, the effect of a noncaloric liquid is not known. The aims of this study were to determine the effect of normal saline given at 3 hr after feeding on gastric antral motor activity and gastric emptying and to evaluate the role of endogenous cholecystokinin in the changes in gastric function induced by postprandial saline intake in conscious dogs. Two cannulas were implanted in each of five mongrel dogs for infusion of phenolsulfonphthalein into the proximal duodenum and for aspiration of luminal samples from the distal duodenum. Gastric contractile and emptying activity were measured by the force transducer method and a freeze-drying method newly developed by our group, respectively. Postprandial pancreaticobiliary secretion was assessed from amylase and bile acid outputs into the duodenum. One hundred grams of freeze-dried dog food was given as a solid meal after mixing it with 100 ml of normal saline. The dogs were given 100 ml of normal saline per os at 3 hr after feeding. In another study, intravenous administration of devazepide, a specific cholecystokinin-A receptor antagonist, at a dose of 0.1 mg/kg/hr was begun 15 min before postprandial saline intake and continued for 1 hr. Gastric antral motility was significantly (P < 0.01) inhibited for 30 min after the dogs had drunk saline at 3 hr after feeding. The mean fractional emptying rate of gastric solids in percentage per 30 min after postprandial saline intake was significantly (P < 0.05) slower than that in the control study without saline intake at 3 hr after feeding. Amylase output into the duodenum after postprandial saline intake showed a gradual increase lasting for about 1 hr, whereas that of bile acid increased transiently but markedly 15 min after saline intake, in comparison with the control study. Pretreatment with devazepide partially ameliorated the suppression of gastric antral motility. Postprandial intake of saline inhibited gastric motor activity and delayed solid gastric emptying, whereas it increased the outputs of amylase and bile acid. Endogenous cholecystokinin may be partially involved in these phenomena caused by saline intake at 3 hr after feeding.