Distilled water peritoneal lavage after colorectal cancer surgery

Lytic effects of water on cancer cells: Implications for post-operative irrigation

BACKGROUND

Intraoperative tumour spillage can be concerning during cancer excisions, given it can lead to tumour-cell re-implantation and local recurrence. Examples include bladder tumour recurrences post-transurethral resection, or peritoneal spillage during laparotomy/laparoscopy for bowel and ovarian cancers. One approach to reducing implantation is mechanical wash out of free-floating tumour cells. Irrigation with water may have additional effectiveness compared to iso-osmotic irrigants (e.g. saline) by causing osmotic cytolysis, but this is not well-characterised. This in vitro study aimed to ascertain the time-course of osmotic effects of water on various cancer cell lines to provide guidance for clinical usage.

METHODS

Assays were conducted on six cancer cell lines (bladder [HT1197, HT1376], colon [KM12, LIM2405], kidney [SKRC52], and ovarian [COV434]). Cells were exposed to water or 0.9% saline and cell counts were performed using a haemocytometer at 10, 20, 40, 60, 120 and 180 min. Cell viability was determined using Trypan Blue exclusion.

RESULTS

In all cell lines, exposure to water led to 100% cell lysis within a median time of 40 min (range 10-180 min), while exposure to saline led to a gradual decline in cell viability (median 50.2%, range 6.7%-100.0%) over 3 h, and did not result in complete cell lysis. An increase in osmotic gradient equivalent to a concentration of 5% NaCl was sufficient to impede the effects of water-mediated cell lysis.

CONCLUSION

Our studies suggest that water has a rapid osmolytic effect on cancer cells. The required exposure time to reach 0% cell viability varied between individual cell lines.

The role of hyperthermic intraperitoneal chemotherapy in the treatment of spontaneously ruptured hepatocellular carcinoma: a pilot study

Background

Spontaneous tumor rupture is a distinctive disease pattern in patients with hepatocellular carcinoma (HCC). The application of hyperthermic intraperitoneal chemotherapy (HIPEC) in spontaneously ruptured hepatocellular carcinoma (srHCC) is debatable. Our study aimed to compare the long-term outcomes of srHCC vs. nrHCC and to test the role of postoperative HIPEC in patients with srHCC after hepatectomy.

Methods

From 2014 to 2018, PSM was performed to compare 57 patients who performed liver resection for srHCC and met the research criteria with 57 nrHCC patients selected from 446 consecutive patients. Then patients with srHCC were divided into two groups according to whether they underwent HIPEC after hepatectomy.

Results

After 1:1 PSM, the clinical characteristics of the patients with srHCC and nrHCC were comparable. In terms of long-term outcomes, the nrHCC group had significantly longer OS (P=0.026) and DFS (P<0.001) than the srHCC group. Of the 57 srHCC patients, the HIPEC group showed added complications compared to the non-HIPEC group, including an increased length of hospital stay and higher in-hospital costs. However, there were no significant differences in the metastatic patterns of these recurrent patients, and there was no statistically significant difference in DFS (P=0.28) or OS (P=0.56) between the two groups.

Conclusions

The prognosis of ruptured HCC patients were worse than those of non-ruptured HCC patients. HIPEC may not be a robust treatment for srHCC now.

Intraoperative radiofrequency ablation and distilled water peritoneal lavage for spontaneously ruptured hepatocellular carcinoma

Purpose

Spontaneously ruptured hepatocellular carcinoma (srHCC) is known to be a life-threatening complication with poor prognosis. Although there are various treatment modalities, there is no definite treatment guideline. The purpose of this study was to review the surgical outcome and prognosis of srHCC treated with intraoperative radiofrequency ablation (RFA) and distilled water peritoneal lavage (DWPL).

Methods

From March 2012 to October 2018, 9 patients with srHCC who underwent emergent surgery were reviewed. After hematoma removal, intraoperative RFA and DWPL were applied to all patients. Hepatectomy was performed if necessary. Patients with multiple tumors, distant metastasis, and vascular tumor involvement in radiologic imaging were excluded.

Results

Six of 9 patients with diameters less than 7 cm were able to obtain hemostasis using RFA alone (RFA group). However, 3 patients with a tumor size of more than 10 cm underwent liver resection because they could not obtain hemostasis with RFA (hepatectomy only group). The RFA group had shorter operation time (148.3 ± 31.7 minutes vs. 251.7 ± 20.2 minutes, P < 0.05) and less red blood cell transfusion (5.8 ± 2.5 packs vs. 24.0 ± 11.5 packs, P < 0.05) than the hepatectomy only group. There was no peritoneal metastasis at long-term follow-up in the RFA group. Five-year recurrence-free survival rate was 0% in both groups. However, 5-year overall survival rate was better in the RFA group (83.3% vs. 0%, P < 0.05).

Conclusion

Intraoperative RFA and DWPL are easy to perform and theoretically the best methods for managing relatively small srHCC.

Effect of low temperature on the regulation of cell volume after hypotonic shock in gastric cancer cells

Although peritoneal lavage with distilled water performed after surgery prevents peritoneal seeding, cancer cells may avoid rupture under mild hypotonicity through regulatory volume decrease (RVD), which is the homeostatic regulation of ion and water transport. The aim of the present study was to investigate the effect of low temperature on cell volume and cell death under hypoosmolal conditions and determine the underlying molecular mechanisms in gastric cancer (GC). Three human GC cell lines (NUGC4, KATO‑III and MKN45) were exposed to hypotonic solutions, and the effects of low temperature on cell volume and viability were examined. Low temperature‑induced changes in membrane transporters were evaluated, and knockdown and overexpression experiments were conducted to determine their effects on cell volume during hypotonic stimulation. Low temperature (24˚C) during hypotonic stimulation inhibited RVD and enhanced the cytocidal effects on GC cells. The expression of leucine‑rich repeat containing protein A (LRRC8A), a component of a Cl‑ channel, was decreased, and aquaporin 5 (AQP5) expression was increased at low temperatures. LRRC8A knockdown markedly slowed the decrease in cell volume following cell swelling by hypotonic shock. AQP5 overexpression enhanced initial cell swelling after hypotonic shock and increased the final cell volume. These results suggest that a hypotonic solution at low temperature increased initial water influx via activation of AQP5 and decreased Cl‑ efflux via inhibition of LRRC8A. Therefore, low temperature enhanced the hypotonicity‑induced cytocidal effects on GC cells, and these results may contribute to the development of a novel lavage method effective in reducing peritoneal recurrence in GC.

Pharmacological mechanisms of the anticancer action of sodium selenite against peritoneal cancer in mice

Peritoneal carcinomatosis has an extremely poor overall prognosis and remains one of the greatest oncologic challenges. Prior studies in mice show that sodium selenite administered intraperitoneally is highly effective in inhibiting cancer cells implanted in the peritoneal cavity. However, the pharmacological mechanism remains unclear. The present study revisited the therapeutic effect of selenite and elucidated its mechanism of action. We found that intraperitoneal delivery of selenite to cancer cells in the peritoneal cavity of mice rapidly and robustly killed the cancer cells, with a therapeutic efficacy higher than that of cisplatin. The action of selenite was associated with the following pharmacological mechanisms. 1) Favorable drug distribution: selenite increased selenium levels in the cancer cells by 250-fold, while in normal tissues only by 7-fold. 2) Optimal selenium form: selenite was converted in the cancer cells mainly into selenium nanoparticles (SeNPs), which are more efficient than selenite in producing reactive oxygen species (ROS). 3) Persistent hijacking of two pro-survival systems to generate ROS: selenite did not impair thioredoxin- and glutaredoxin-coupled glutathione systems, which facilitate SeNPs to generate ROS and caused severe organelle injury and apoptotic response in the cancer cells. Overall, these mechanisms tend to maximize the potential of selenite in producing ROS in cancer cells and underlie selenite as a candidate therapeutic agent for peritoneal carcinomatosis.

Gastric washing by distilled water can reduce free gastric cancer cells exfoliated into the stomach lumen

PURPOSE

Intragastric free cancer cells in patients with gastric cancer have rarely been studied. The purpose of this study was to investigate the detection rate of intragastric free cancer cells in gastric washes using two types of solutions during endoscopic examination. We further clarified risk factors affecting the presence of exfoliated free cancer cells.

METHODS

A total of 175 patients with gastric cancer were enrolled. Lactated Ringer's solution (N = 89) or distilled water (DW; N = 86) via endoscopic working channel was sprayed onto the tumor surface, and the resultant fluid was collected for cytological examination. We compared the cancer-cell positivity rate between the two (Ringer and DW) groups. We also tested the correlation between cancer-cell positivity and clinicopathological factors in the Ringer group to identify risk factors for the presence of exfoliated cancer cells.

RESULTS

The cancer-cell positivity rate was significantly higher in the Ringer group than that in the DW group (58 vs 6%). Cytomorphology in the Ringer group was well maintained, but not in the DW group. The larger tumor size (≥ 20 mm) and positive lymphatic involvement were significant risk factors of exfoliated free cancer cells.

CONCLUSIONS

Cancer cells can be highly exfoliated from the tumor surface into the gastric lumen by endoscopic irrigation in large gastric cancer with lymphatic involvement. Gastric washing by DW can lead to cytoclasis of free cancer cells; therefore, it may minimize the possibility of cancer-cell seeding in procedures carrying potential risks of tumor-cell seeding upon transluminal communication, such as endoscopic full-thickness resection and laparoscopy-endoscopy cooperative surgery.

Safety and efficacy of dehydrated ethanol soaking of the operative field in the treatment of spontaneous hepatocellular carcinoma rupture

Background

The aim of our study was to evaluate the clinical safety and value of ethanol surgical field infiltration (ESFI), combined with distilled water peritoneal lavage (DWPL), after hepatectomy in patients with hepatocellular carcinoma (HCC) rupture.

Methods

Rat liver tissue samples were soaked in dehydrated ethanol for different soaking times, and 18 rats were assigned to three groups that underwent different soaking methods of the hepatectomy cut surface. We retrospectively reviewed 45 patients who underwent hepatectomy for treatment of ruptured HCC. Among these, EFSI combined with DWPL was used in 21 patients (DAW group), with only DWPL used in the other 24 patients (DW group). Clinical outcomes were compared between the two groups.

Results

For in vitro experiments, the depth of coagulation degeneration and necrosis increased with the duration of soaking. For in vivo experiments, rats in all three groups survived until postoperative day 7 without significant postoperative complication. In patients, the rate of post-operation complication was comparable between the two groups (P = 0.398), with no between-group differences in liver function levels. The incidence of peritoneal dissemination was significantly higher for DW than DAW group (P = 0.037). Kaplan–Meier test identified dehydrated ethanol treatment as a significant factor of disease-free survival (DFS) (P = 0.036). On univariate analysis, dehydrated ethanol treatment was associated with better prognostic outcomes, although it was not retained as an independent factor of patient outcome.

Conclusions

Dehydrated ethanol soaking of the cut surface of the hepatectomy could potentially lower the risk of metastasis and improve the effect of hepatectomy for ruptured HCC as well as showed potential therapeutic value for intraoperative iatrogenic rupture of HCC.

Electronic supplementary material

The online version of this article (10.1186/s12957-018-1390-x) contains supplementary material, which is available to authorized users.

Blockade of potassium ion transports enhances hypotonicity-induced cytocidal effects in gastric cancer

Background

Peritoneal lavage with distilled water has been used for surgeries of various cancers to reduce peritoneal recurrence. This study examined whether blockade of potassium ion transports enhances hypotonicity-induced cytocidal effects in gastric cancer (GC).

Results

A potassium channel blocker inhibited the occurrence of regulatory volume decrease (RVD) induced by mild hypotonic stimulation, and significantly enhanced cytocidal effects on GC cells. Incubating MKN45 cells with hypotonic solutions containing a potassium channel blocker significantly reduced the formation of peritoneal metastases in nude mice.

Methods

The three human GC cell lines (HGC-27, Kato III, and MKN45) were exposed to mild hypotonic solutions, and the effects of blockade of potassium ion transports during hypotonic stimulation on cell volume changes and cell viabilities were examined. In the in vivo study, MKN45 cells stimulated with mild hypotonic solutions were intraperitoneally injected into nude mice, and the effects of blockade of potassium ion transports during hypotonic stimulation on the formation of peritoneal metastases were evaluated.

Conclusions

Blockade of potassium ion transports enhances hypotonicity-induced cytocidal effects on GC cells, which may contribute to development of a novel lavage method for further reduction of peritoneal recurrence in GC.

Water lavage as an adjunct to cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC)

BACKGROUND

Water lavage (WL) during gastrointestinal cancer surgery has osmotically mediated lytic effects on tumor cells. We investigated the safety and efficacy of WL with CRS-HIPEC.

METHODS

This is a retrospective review, 1/2003-7/2014, of a single institution experience with CRS-HIPEC comparing patients who had WL (WL+) to those who did not (WL-).

RESULTS

Of 157 CRS-HIPECs, 16 (10.2%) were WL+. WL+ had more PCI scores >20 compared to WL- (56.3% vs 19.4%, respectively, p = 0.003); however, the completeness of cytoreduction (CC) was similar. There were no differences in hospital length of stay or post-operative complications. The average POD 1 sodium (Na) level was statistically lower in the WL+ group (133.6 ± 2.5 vs 135.5 ± 3.2 mEq/L, p = 0.023); however, the average Na at discharge for each group was 140 mEq/L. There were no differences in 3-year OS (3WL+:0.63 vs WL-:0.68, p = 0.97) or RFS (WL+:0.32 vs WL-:0.39, p = 0.47). A subset analysis for patients with PCI >20 showed no difference between groups.

CONCLUSIONS

WL offers a low cost, safe and theoretically efficacious method of tumor cell lysis for peritoneal malignancy.

Regulation of osmolality for cancer treatment

Disseminated metastasis is associated with a poor prognosis, and its management in the peritoneal or pleural cavity is crucial in the treatment of cancer. Recent studies show that ion and water transporters play important roles in fundamental cellular functions, including the regulation of cell volume that would be involved in the cancer process. Here, we review the evidence for hypotonic treatments of cancer and evaluate the potential of the cellular physiological approach in clinical management. The regulation of extracellular osmolality is a promising method, with several studies demonstrating the cytocidal effects of hypotonic solution on cancer cells. Peritoneal lavage with distilled water (DW) during surgery is reported to improve the survival rate of patients with spontaneously ruptured hepatocellular carcinoma. The in vitro studies included in this review also indicate the cytocidal effects of hypotonic shock on esophageal, gastric, colonic, pancreatic, and liver cancer cells with several unique methods and apparatuses, such as a differential interference contrast microscope connected to a digital video camera, a high-resolution flow cytometer and re-incubation analysis. The in vivo studies demonstrate the safeness of a peritoneal injection of DW into mice and indicate that the development of dissemination nodules can be prevented by the pre-incubation of cancer cells with DW or the peritoneal injection of DW. We also demonstrate that the blockade of Cl- channels/transporters enhances the cytocidal effects of hypotonic shock by inhibiting regulatory volume decrease in various cancer cells. A deeper understanding of molecular mechanisms may lead to the discovery of these cellular physiological approaches as a novel therapeutic strategy for disseminated metastasis.

Distilled Water Lavage During Surgery Improves Long-Term Outcomes of Patients with Ruptured Hepatocellular Carcinoma

BACKGROUND

Rupture of hepatocellular carcinoma (HCC) releases tumor cells and furthers peritoneal metastasis. The present study investigated the killing effects of distilled water (DW) on HCC cells and the clinical outcomes of patients undergoing liver resection with DW lavage for spontaneously ruptured HCC.

MATERIALS AND METHODS

Human HCC cells (BEL-7402, SMMC7721) were treated with DW, the morphological changes observed, and cell viability measured. DW-treated HCC cells were also injected intraperitoneally into nude mice, and the formation of tumor nodules and overall survival (OS) measured. The clinicopathological data of 141 consecutive patients undergoing liver resection for spontaneously ruptured HCC during 1998-2011 were retrospectively reviewed.

RESULTS

Fifteen minutes of DW exposure caused complete cell lysis of HCC cells in vitro and completely prevented tumor formation and prolonged survival time in nude mice. Among the 141 patients, the 1-, 3-, and 5-year disease-free survival (DFS) and OS rates in patients administered DW lavage during surgery were 68.9, 24.6, and 6.6%, respectively, and 95.1, 65.1, and 40%, respectively, which were significantly higher than those in patients who did not (P < 0.05). DW lavage was an independent predictor of recurrence (odds ratio (OR), 0.34; 95% confidence interval (CI), 0.23-0.51; P < 0.001) and OS (OR, 0.35; 95% CI, 0.23-0.53; P < 0.001).

CONCLUSIONS

Fifteen minutes of DW lavage can effectively kill HCC cells in vitro and prevent tumor formation in vivo. DW lavage significantly improves long-term outcomes in patients undergoing liver resection for spontaneously ruptured HCC and could be administered intra-operatively when tumor cell liberation is suspected.

In-vitro cytocidal effect of water on bladder cancer cells: The potential role for intraperitoneal lavage during radical cystectomy

INTRODUCTION

We investigate the cytocidal effect of water on bladder cancer cells. Intraperitoneal lavage with sterile water is sometimes used during radical cystectomy to lyse cancer cells that might have escaped the surgical specimen. The efficacy of this approach at the cellular level is unknown.

METHODS

Three bladder cancer cell lines of varying grade, RT4, TCCSUP and T24 were exposed to sterile water, and morphological changes were closely observed under microscopy. Changes of cell membrane integrity, cell viability, and cell number of re-incubated cells after water exposure were measured to determine water induced hypotonic shock.

RESULTS

The low-grade RT4 cells started swelling immediately upon exposure to water followed by rupture within 3 minutes. The higher grade TCCSUP and T24 cells demonstrated limited hypotonic swelling with significantly less cell rupture after 10 minutes. The damage to cell membrane of RT4 cells was evident at 1 minute; only 10.0% of cells were intact at 10 minutes. On the other hand, 41.9% and 77.8% of TCCSUP and T24 cells were intact at 10 minutes, respectively. Percentage of viable cells at 10 minutes was 2.1 ± 2.3%, 2.3 ± 0.4%, and 16.1 ± 0.6% for RT4, TCCSUP, and T24, respectively.

CONCLUSIONS

Cytocidal effect of hypotonic shock can be achieved, to varying degrees, by exposing bladder cancer cells to water for at least 10 minutes. This in vitro study may have bearing on the effects seen with intraperitoneal lavage using sterile water during radical cystectomy.

Evaluation of the efficacy of peritoneal lavage with distilled water in colorectal cancer surgery: in vitro and in vivo study

BACKGROUND

Peritoneal lavage with distilled water has been performed during colorectal cancer surgery. This study investigated the cytocidal effects of hypotonic shock in vitro and in vivo in colorectal cancer cells.

METHODS

Three human colorectal cancer cell lines, DLD1, HT29, and CACO2, were exposed to distilled water, and morphological changes were observed under a differential interference contrast microscope connected to a high-speed digital video camera. Cell volume changes were assessed using a high-resolution flow cytometer. Re-incubation experiments were performed to investigate the cytocidal effects of distilled water. In the in vivo experiment, cancer cells after hypotonic shock were injected intraperitoneally into mice and the degree of established peritoneal metastasis was subsequently evaluated. The effects of the blockade of Cl(-) channels on these cells during hypotonic shock were also analyzed.

RESULTS

Morphological observations revealed a rapid cell swelling followed by cell rupture. Measurements of cell volume changes showed that mild hypotonic shock induced regulatory volume decrease (RVD) while severe hypotonic shock broke cells into fragments. Re-incubation experiments demonstrated the cytocidal effects of hypotonicity. In vivo experiments revealed the absence of peritoneal dissemination in mice in the distilled water group, and its presence in all mice in the control group. The blockade of Cl(-) channels increased cell volume by inhibiting RVD and enhanced cytocidal effects during mild hypotonic shock.

CONCLUSIONS

These results clearly support the efficacy of peritoneal lavage with distilled water during colorectal cancer surgery and suggest that regulating of Cl(-) transport may enhance the cytocidal effects of hypotonic shock.

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

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

Irrigation solutions in head and neck cancer surgery: a preclinical efficacy study

INTRODUCTION

It is common practice to irrigate the operative site following tumor resection during major head and neck surgery. A variety of irrigation solutions are used, but there are few data on their relative efficacies in this context.

METHODS

The effect of different irrigation solutions on cell survival was assessed by clonogenic survival assay in 5 head and neck squamous cell carcinoma cell lines at different time points.

RESULTS

Saline had no effect on cell survival in any of the cell lines tested. Hydrogen peroxide, povidone-iodine, and a hydrogen peroxide/povidone-iodine mix caused complete cell death in all cell lines. Irrigation with distilled water caused a significant reduction in cell survival in 3 cell lines. Duration of exposure showed no effect on cell survival.

CONCLUSION

These data suggest a significant difference in the cytocidal effect of commonly used irrigation solutions on head and neck cancer cells in an in vitro model.

Efficacy of a hypotonic treatment for peritoneal dissemination from gastric cancer cells: an in vivo evaluation

The aim of the present study was to determine the efficacy of a hypotonic treatment for peritoneal dissemination from gastric cancer cells using an in vivo model. We firstly evaluated the toxicity of a peritoneal injection of distilled water (DW) (2 mL for 3 days) in mice. Macroscopic and microscopic examinations revealed that the peritoneal injection of DW did not severely damage the abdominal organs of these mice. MKN45 gastric cancer cells preincubated with NaCl buffer or DW for 20 minutes in vitro were then intraperitoneally injected into nude mice, and the development of dissemination nodules was analyzed. The total number, weight, and volume of the dissemination nodules were significantly decreased by the DW preincubation. We then determined whether the peritoneal injection of DW inhibited the establishment of peritoneal dissemination. After a peritoneal injection of MKN45 cells into nude mice, NaCl buffer or DW was injected into the abdominal cavity for 3 days. The total volume of dissemination nodules was significantly lower in DW-injected mice than in NaCl-injected mice. In conclusion, we demonstrated the safeness of a peritoneal injection of DW. Furthermore, the development of dissemination nodules from gastric cancer cells was prevented by a preincubation with or peritoneal injection of DW.

Efficacy and safety of selenium nanoparticles administered intraperitoneally for the prevention of growth of cancer cells in the peritoneal cavity

Peritoneal implantation of cancer cells, particularly postoperative seeding metastasis, frequently occurs in patients with primary tumors in the stomach, colon, liver, and ovary. Peritoneal carcinomatosis is associated with poor prognosis. In this work, we evaluated the prophylactic effect of intraperitoneal administration of selenium (Se), an essential trace element and a putative chemopreventive agent, on peritoneal implantation of cancer cells. Elemental Se nanoparticles were injected into the abdominal cavity of mice, into which highly malignant H22 hepatocarcinoma cells had previously been inoculated. Se concentrations in the cancer cells and tissues, as well as the efficacy of proliferation inhibition and safety, were evaluated. Se was mainly concentrated in cancer cells compared to Se retention in normal tissues, showing at least an order of magnitude difference between the drug target cells (the H22 cells) and the well-recognized toxicity target of Se (the liver). Such a favorable selective distribution resulted in strong proliferation suppression without perceived host toxicity. The mechanism of action of the Se nanoparticle-triggered cytotoxicity was associated with Se-mediated production of reactive oxygen species, which impaired the glutathione and thioredoxin systems. Our results suggest that intraperitoneal administration of Se is a safe and effective means of preventing growth of cancer cells in the peritoneal cavity for the above-mentioned high-risk populations.

Intrapleural hyperthermic perfusion using distilled water at 48 °C for malignant pleural effusion

BACKGROUND

To evaluate the feasibility, safety and preliminary efficacy of B-ultrasound-guided continuous circulatory intrapleural hyperthermic perfusion (IHP) with distilled water (DW) at 48 °C, for the treatment of malignant pleural effusion (MPE).

METHODS

Prospective, randomized interventional study in China (from December 2008 to December 2011) in adults with MPE originating from disseminated pleural tumor.

EXCLUSION CRITERIA

thoracotomy or surgical resection, limited encapsulated pleural effusion or extensive pleural adhesions. Patients were randomly divided into DW (12 patients; B-ultrasound-guided IHP with 48 °C DW) and PSS-C (11 patients; B-ultrasound-guided IHP with 45 °C physiological saline solution and cisplatin) groups. Patients were followed up for assessment of objective MPE remission rate, Karnofsky performance scale (KPS) scores and survival duration.

RESULTS

Pleural effusion was controlled in 100 % of patients, and mean KPS score was increased by 40 % after therapy. Patients' median survival times in the DW and PSS-C groups were 13.0 and 12.9 months, respectively. No serious clinical complications were observed. There were no significant differences between groups in the total objective MPE remission rate, mean KPS score change or median survival time, demonstrating the achievement of significant clinical efficacy with our modified IHP.

CONCLUSION

Intrapleural hyperthermic perfusion with 48 °C DW is feasible, easy to perform and relatively safe. This method may offer excellent local control for patients with MPE secondary to disseminated pleural lesions.

Enhancement of the cytocidal effects of hypotonic solution using a chloride channel blocker in pancreatic cancer cells

BACKGROUND

Tumor cells exfoliated during surgery for pancreatic cancer can cause peritoneal recurrence. Peritoneal lavage with distilled water has been performed during surgery, but there have been no systematic studies for its efficacy and no experimental data demonstrating the cytocidal effects of distilled water on pancreatic cancer cells. This study investigated the cytocidal effects of hypotonic shock and enhancement using chloride channel blocker in pancreatic cancer cells.

METHODS

Three human pancreatic cancer cell lines, KP4-1, PK-1, and PK45-H, were exposed to distilled water, and the resultant morphological changes were observed under a differential interference contrast microscope connected to a high-speed video camera. Analysis of cell volume changes was performed using a high-resolution flow cytometer. To investigate the cytocidal effects of water, re-incubation of cells was performed after exposure to hypotonic solution. Additionally, the effects of 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), a Cl(-) channel blocker, on cells during exposure to hypotonic solution were analyzed.

RESULTS

Video recordings demonstrated that hypotonic shock induced cell swelling followed by cell rupture. Measurement of cell volume changes indicated that severe hypotonicity increased broken fragments of cancer cells within 5 min. Re-incubation experiments demonstrated the cytocidal effects of hypotonic shock. In all cell lines, treatment with NPPB increased cell volume by inhibiting regulatory volume decreases, which are observed during hypotonic shock, and enhanced the cytocidal effects of hypotonic solution.

CONCLUSIONS

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

Washout after lobectomy: is water more effective than normal saline in preventing local recurrence?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was: 'is water washout more effective than normal saline washout after lobectomy in preventing local recurrence?' Altogether more than 48 papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Tumour cell 'spillage' after cancer resection is linked to a worse prognosis, so washout to minimize contamination is an established surgical technique. While the mechanical effects of lavage are well validated, the differential cytocidal effects of water versus saline as irrigation fluids are not. There are currently no studies addressing this issue in the thoracic surgery setting, after lung cancer lobectomy. However, the majority of relevant papers describe the use of basic in vitro methods and animal models to produce data that can conceivably be extrapolated to the clinical question in hand. The number of studies is small, and some have technical limitations. While two of the better-designed experiments suggest that water exerts a superior cytocidal effect on tumour cells, data from other studies are somewhat unimpressive, with two studies reporting that water washout controls tumour growth to a lesser extent than saline. This, together with the complete paucity of clinical trials on the subject, leads us to conclude that water is unlikely to represent a superior irrigation fluid in lung cancer patients after lobectomy.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Selection of irrigation fluid to eradicate free cancer cells during head and neck cancer surgery

BACKGROUND

Free cancer cells can be spilled out from exposed tumors or ruptured tumors. We examined the cytocidal effect of various irrigation fluids on free cancer cells in an animal wound model mimicking head and neck surgery.

METHODS

Cancer cell-contaminated wounds were made with C3H/HeJ mice and syngeneic squamous cell carcinoma (SCC VII) cells. Distilled water, 5% povidone-iodine, 1.5% H(2)O(2), normal saline, and cisplatin were used to irrigate for 5 minutes. In vitro tumor growth assays were done with different concentrations and exposure times of povidone-iodine and distilled water.

RESULTS

In the animal study, povidone-iodine significantly inhibited tumor growth. Povidone-iodine caused substantial inhibition of in vitro tumor growth, even at the concentration of 0.05%. After 30 seconds of exposure to 1% povidone-iodine, cancer cells were completely inhibited.

CONCLUSIONS

Povidone-iodine could be selected preferentially for the irrigation fluid during head and neck surgery, especially when the wound is suspected of cancer cell contamination.

Water: a simple solution for tumor spillage

BACKGROUND

Although often proposed as a means to reduce the harmful consequences of tumor spill, water lavage has yet to be systematically evaluated in relevant in vitro and in vivo models. This study evaluates the mechanisms and utility of a single water lavage to improve the sequelae of tumor spill during laparotomy.

METHODS

Murine colorectal tumor cell susceptibility to water-induced osmotic lysis was characterized in vitro. A reproducible model of tumor spill was established to recapitulate water or saline lavage during laparotomy. Analyses of tumor volumes calculated from noninvasive imaging were performed. The tumor volumes and survival of mice treated with water, normal saline, or sham laparotomy were assessed.

RESULTS

Significant osmotic lysis of cultured murine colorectal cancer cells was observed after a brief exposure to water. Compared to saline or sham laparotomy, water lavage demonstrated superior clinical outcomes with a decrease in tumor burden and concomitant improvement in survival.

CONCLUSIONS

The use of water lavage during oncologic surgeries to reduce the sequelae of tumor spill is justified and strongly supported by our study. Data from our study raise several concerns regarding the mechanisms and efficacy of saline lavage. Clinically, the use of water lavage during laparotomy would be anticipated to reduce peritoneal disease burden with minimal toxicity or cost.

Prevention and treatment of transitional cell carcinomatosis with intraperitoneal chemotherapy in a rat model

PURPOSE

Tumor spillage from bladder perforation during transurethral bladder tumor resection or cystectomy risks seeding the peritoneum with transitional cell carcinoma. We determined the lowest effective mitomycin C dose to prevent tumor implantation and the potential efficacy of delayed therapy. Additionally, we investigated the effect of tumor debulking combined with intraperitoneal mitomycin C.

MATERIALS AND METHODS

Using our established murine model of intraperitoneal transitional cell carcinoma implantation mitomycin C was instilled at decreasing concentrations to find the lowest effective dose. To evaluate the effectiveness of delayed therapy mitomycin C was administered on day 3 or 7 after tumor implantation. Finally, surgical debulking of established tumors with or without mitomycin C was performed.

RESULTS

All control animals had disseminated carcinomatosis. The lowest effective intraperitoneal mitomycin C dose to prevent implantation was 0.3125 mg/m(2). Administration of mitomycin C on day 3 after instillation resulted in tumor-free status in 50% of the animals, although no rats were tumor-free when treated on day 7. Tumor debulking only for established disease cured 40% of the animals, whereas debulking combined with mitomycin C had a 100% cure rate.

CONCLUSIONS

Intraperitoneal mitomycin C prevents tumor growth after transitional cell carcinoma implantation. Delayed therapy is not as effective as immediate treatment but cure is still possible, particularly when combined with surgical debulking, in a rat model.

Radioimmunotherapy prevents local recurrence of colonic cancer in an experimental model

Background

Radioimmunotherapy (RIT) is suitable for the treatment of microscopic residual disease and might therefore have an adjuvant role after colonic cancer surgery.

Methods

An anastomosis was constructed in male Wag/Rij rats after intraluminal injection of 2 × 106 CC531 tumour cells. The biodistribution of 111In-labelled MG1 monoclonal antibody was assessed after intraperitoneal administration. The therapeutic efficacy of 177Lu-labelled MG1 (74 MBq per rat), administered on the day of surgery (D0, n = 13) or 5 days later (D5, n = 13), was compared with that of carrier only (n = 13). The primary endpoint was perianastomotic tumour growth 28 days after surgery.

Results

111In-labelled MG1 preferentially accumulated in perianastomotic CC531 tumours. RIT resulted in a transient reduction in bodyweight in both treatment groups compared with controls, but there were no other signs of clinical discomfort. No macroscopic or microscopic perianastomotic tumour growth was found in eight of 11 animals in the D0 group and 11 of 13 in the D5 group, whereas 11 of 13 controls had macroscopic tumour (P = 0·011 and P = 0·001 respectively).

Conclusion

This study suggests that RIT may be an effective adjuvant treatment for preventing local recurrence after resection of colonic cancer.

The use of distilled water in the achievement of local hemostasis during surgery

Distilled water is used worldwide to check on hemostasis at the end of pelvic oncological operations. Nevertheless, reports about this method are lacking. The aim of this study was to explain the method and to discuss possible side effects. After the addition of distilled water to the surgically exposed pelvis, rapid lysis of erythrocytes results in a transparent fluid in which a small source of bleeding is easily recognizable. A possible side effect of the lavage might be contribution to the formation of peritoneal adhesions by confusing the abdominal defence system. Systemic side effects are not to be expected. Although tumour cells might suffer from hypotonic distilled water lavage, the current use of distilled water at the end of surgery is probably not effective to lyse tumour cells. Our findings support the ongoing use of distilled water lavage to achieve hemostasis after extensive pelvic surgery.

Peritoneal minimal residual disease in colorectal cancer: mechanisms, prevention, and treatment

Roughly one in five patients with colorectal cancer develops peritoneal minimal residual disease after surgical resection, and about one in seven patients develops peritoneal carcinomatosis. By contrast with the vast body of research addressing haematogenous metastasis, little is known about the biology of peritoneal spread of colorectal cancer. The development of peritoneal carcinomatosis involves well-defined steps including cell shedding and transport, adhesion to the mesothelial layer, invasion of and proliferation into the submesothelial stroma, and potential access to the systemic circulation. In this Review, we summarise the molecular mechanisms and potential preventive measures associated with each step of the peritoneal metastatic cascade.

Benefits of povidone-iodine solution in colorectal operations: science or legend

Povidone-iodine solution (Betadine) has long been accepted as an effective topical broad spectrum antiseptic, disinfectant, and tumoricidal agent. In colorectal operations, this solution generally has been used for the purpose of minimizing postoperative septic complications and reducing cancer recurrence, although the optimal application, advantages, and undesirable side effects have been debated. With limited prospective, randomized, controlled trials and insufficient data available, this article examines the safe and effective clinical applications of this solution for colorectal operations.

Osmotic Selection of Human Mesenchymal Stem/Progenitor Cells from Umbilical Cord Blood

The isolation of undifferentiated adult stem/progenitor cells remains a challenging task primarily due to the rare quantity of these cells in biological samples and the lack of unique markers. Herein, we report a relatively straightforward method for isolation of human mesenchymal stem cells (MSCs) based on their unusual resistance to osmotic lysis, which we term "osmotic selection" (OS). MSCs can remarkably withstand significant exposure to hypotonic conditions (> 30 min) with only a reversible impairment in cell proliferation and with no loss of stem cell potential after exposure. Comparison of MSCs to other circulating nonhematopoietic cells revealed a time regime, by which purification of these cells would be attainable without considerable cell loss. OS showed a 50-fold enrichment of fibroblast colony-forming units from umbilical cord blood samples when compared to commonly employed techniques. After upstream processing, isolated cells using OS were immunophenotyped to be CD14-, CD34-, CD45-, CD44+, CD105+, and CD106+, and displayed multipotent differentiation. Preliminary investigations to determine mechanisms responsible for osmolytic resistance revealed MSCs to have an ineffective volume of 59%, with the ability to double cell volume at infinite dilution. Disruption of filamentous actin polymerization by cytochalasin D sensitized MSCs to osmotic lysis, which suggests a cytoskeletal element involved in osmolytic resistance.

Peritoneal lavage with distilled water during liver resection in patients with spontaneously ruptured hepatocellular carcinomas

Spontaneously rupture of hepatocellular carcinoma is a life threatening and worse prognosis. Not only the lower rate of resection and hemodynamic unstable, but also the hepatic failure and recurrence. Distilled water irrigation had been applied in several cancer surgeries including colon, stomach, breast, ovary, and bladder; thus had good results in lowering the tumor spreading. We applied distilled water peritoneal lavage after liver resection in patients with spontaneous rupture of hepatocellular carcinoma to define the influence of prognosis. Thirteen patients with spontaneous ruptured hepatocellular carcinoma underwent distilled water peritoneal lavage after curative liver resection (Group A). Nineteen patients with spontaneous ruptured hepatocellular carcinoma did not undergo distilled water peritoneal lavage after curative liver resection (Group B). There were 11 patients of tumor recurrence in Group B; 2 in Group A. The mean disease-free time of Group B was 2.05 +/- 0.74 years; for Group A it was 3.59 +/- 0.60 (P = 0.045). Peritoneal lavage in this series resulted in significantly better survival time for the patients in Group A (P = 0.0158). That implies distilled water peritoneal lavage during liver resection would retard the tumor recurrence and further improve the survival rate in patients with spontaneously ruptured hepatocellular carcinoma.

Intraperitoneal Chemotherapy for the Prevention of Transitional Cell Carcinoma Implantation

PURPOSE

Tumor spillage from bladder perforation during transurethral resection of a bladder tumor or during cystectomy risks seeding the peritoneum with TCC. Current therapy is irrigation with sterile water with an unknown extent of clinical benefit. Intraperitoneal chemotherapy for other human cancers has demonstrable benefit but to our knowledge it has never been investigated for TCC. We investigated whether intraperitoneal chemotherapy can prevent TCC implantation in a murine model of tumor spillage and whether water irrigation is beneficial.

MATERIALS AND METHODS

Laparotomy was performed in 28 Fischer 344 rats (National Cancer Institute, Frederick, Maryland) to instill 1 x 10 AY-27 TCC cells. Mitomycin (10 mg/m) was instilled in 9 rats and saline was used in the control group. A third group underwent lavage with sterile water. At sacrifice after 2 weeks tumors were measured in mm and weighed. A followup experiment of 4-week survival used 5 mg/m mitomycin and added a fourth group treated with water lavage plus mitomycin.

RESULTS

All 9 rats in the saline control group had gross tumors at the laparotomy site as well as gross carcinomatosis. The 10 water lavage rats also demonstrated gross tumors but of smaller size (p = 0.02). All rats treated with mitomycin had no gross or microscopic evidence of tumor growth anywhere in the peritoneum. In experiment 2 none of the rats treated with lower dose mitomycin had gross or microscopic tumors regardless of water lavage.

CONCLUSIONS

Intraperitoneal chemotherapy prevents TCC implantation in a murine model of tumor spillage. Water lavage decreases the tumor burden but it cannot effectively sterilize the peritoneum of tumor.