Effect of intraperitoneal chemotherapy and fibrinolytic therapy on tumor implantation in wound sites

An autopsy case of primary jejunal pouch cancer which protruded from the abdominal wall 14 years after total gastrectomy for gastric cancer

Adenocarcinoma which develops in the jejunal pouch has rarely been reported, but most of such cases tend to be a recurrence of primary cancer due to the presence of residual or disseminated cancer cells. Primary jejunal pouch cancer is extremely rare. We experienced an autopsy case of primary jejunal pouch cancer which occurred 14 years after proximal gastrectomy for gastric cancer. A female in her late 60s was admitted because of hypoglycemia with liver dysfunction. She underwent total gastrectomy for fundic cancer and had been reconstructed by jejunal pouch interposition 14 years prior to this presentation. Hypoglycemia recovered by nutritional support. Computed tomography demonstrated severe fatty liver and liver biopsy proved non-alcoholic steatohepatitis, which was supposed to have been induced by malnutrition. Screening esophagogastroduodenoscopy (EGD) revealed no tumorous lesions in the jejunal pouch at this time. However, her anorexia gradually progressed and the symptom of bowel obstruction appeared. EGD performed 5 months after the previous EGD revealed adenocarcinoma which extended from the anastomosis of the interposed jejunum. Then liver metastasis developed and jejunal pouch cancer invaded the abdominal wall and protruded with ulcer formation. Finally, the patient died of malnutrition. An autopsy revealed adenocarcinoma which had developed in the interposed jejunal pouch and protruded through the abdominal wall accompanied with lung and liver metastasis. We herein describe this rare case of primary interposed jejunal pouch cancer and discuss our findings including a review of the pertinent literature.

Peritoneal Carcinomatosis: Feature of Dissemination a Review

Peritoneal carcinomatosis is a common event that develops in the natural history of many neoplastic diseases, representing a major problem encountered in cancer management. Peritoneal seedings are often associated with neoplastic ascites resulting in a source of significant discomfort to the patient. Considered in the past as a terminal condition, peritoneal carcinomatosis was approached during the last two decades as a curable disease. The introduction of cytoreductive surgery or peritonectomy in the treatment of peritoneal neoplastic diseases drastically changed the natural history of peritoneal carcinomatosis. Another technique that showed an important impact on disease control is intraperitoneal hyperthermic perfusion, one of the most fascinating treatments of peritoneal carcinomatosis that results in an impressive increase in overall survival and quality of life in treated patients with low morbidity. This review illustrates the modality of dissemination of peritoneal carcinomatosis in relation to the primary tumor site and grade of malignancy. Peritoneal carcinomatosis is a term used to define an advanced stage of many abdominal neoplastic diseases that differ in biologic aggressiveness and prognosis. The different presentation of peritoneal carcinomatosis in relation to a different primary tumor and different grade of malignancy strongly influences the potentially therapeutic radical approaches using new and advanced modalities like cytoreductive surgery and intraperitoneal hyperthermic perfusion.

Fabrication and Use of Poly(d,l-lactide-co-glycolide)-Based Formulations Designed for Modified Release of 5-Fluorouracil

5-fluorouracil (5-FU) is a chemotherapeutic agent that has been used for the treatment of a variety of malignancies since its initial introduction to the clinic in 1957. Owing to its short biological half-life, multiple dosings are generally required to maintain effective 5-FU plasma concentrations throughout the therapeutic period. Clinical studies have shown that continuous 5-FU administration is generally superior to bolus injection as exhibited by lower toxicities and increased therapeutic efficacy. Optimal therapeutic efficacy, however, is often compromised by the limiting therapeutic index. Whilst oral formulations are also used, these suffer from the drawbacks of variable bioavailability and first-pass metabolism. As a result, sustained release formulations of 5-FU have been investigated in an effort to mimic the kinetics of continuous infusion particularly for situations where local delivery is considered appropriate. The biocompatible, biodegradable, and highly tunable synthetic polymer, poly(d,l-lactide-co-glycolide) (PLGA), is widely used as a vector for sustained drug delivery, however, issues such as insufficient loading and inappropriate burst release kinetics have dogged progress into the clinic for small hydrophilic drugs such as 5-FU. This review provides introductory information about the mechanism of action, pharmacokinetic and physicochemical properties, and clinical use of 5-FU that have contributed to the development of PLGA-based 5-FU release platforms. In addition, this review provides information on fabrication methods used for a range of 5-FU-loaded PLGA formulations and discusses factors affecting the release kinetics of 5-FU as well as the in vitro and in vivo antitumor or antiproliferative efficacy of these platforms.

Antitumor Efficacy and Toxicity of 5-Fluorouracil-Loaded Poly(Lactide Co-glycolide) Pellets

The aim of this study was to formulate a biodegradable implant capable of imparting local antitumor activity through the sustained release of the chemotherapeutic agent, 5-fluorouracil (5-FU). Thus, injectable pellets (<1.2 mm diameter) made from poly(lactide co-glycolide) (PLGA) and loaded with 5-FU at varying drug:polymer ratios were fabricated using hot-melt extrusion and tested for their ability to provide sustained release of 5-FU in in vitro and in vivo settings. In addition, these formulations were compared against soluble 5-FU for their antitumor activity in vivo as well as for their toxicity. It was demonstrated that the release rate of 5-FU from PLGA pellets was directly related to the percentage of 5-FU in the pellets. PLGA pellets loaded with 50% w/w 5-FU exhibited comparable, and significantly enhanced, antitumor activity (as measured by tumor volumes and survival) in vivo in a thymoma and colon cancer model, respectively, when compared to an equivalent bolus dose (120 mg/kg) of soluble 5-FU. We concluded that 5-FU-loaded PLGA pellets were more effective and specifically less erythrotoxic than 5-FU bolus injections and therefore may prove to be of benefit as an intraoperative adjunct therapy for patients with cancers that are sensitive to 5-FU and who are undergoing tumor resection.

Animal models of colorectal peritoneal metastasis

Colorectal cancer remains an important cause of mortality worldwide. The presence of peritoneal carcinomatosis (PC) causes significant symptoms and is notoriously difficult to treat. Therefore, informative preclinical research into the mechanisms and possible novel treatment options of colorectal PC is essential in order to improve the prognostic outlook in these patients. Several syngeneic and xenograft animal models of colorectal PC were established, studying a wide range of experimental procedures and substances. Regrettably, more sophisticated models such as those giving rise to spontaneous PC or involving genetically engineered mice are lacking. Here, we provide an overview of all reported colorectal PC animal models and briefly discuss their use, strengths, and limitations.

Intraoperative versus early postoperative intraperitoneal chemotherapy after cytoreduction for colorectal peritoneal carcinomatosis: an experimental study

BACKGROUND

Perioperative intraperitoneal chemotherapy is used as an adjunct to cytoreductive surgery (CS) for peritoneal carcinomatosis (PC) in order to prolong survival. Worldwide, hyperthermic intraperitoneal chemotherapy (HIPEC), early postoperative intraperitoneal chemotherapy (EPIC), and combinations of the two are used. It remains unclear which regimen is most beneficial.

METHODS

The rat colon carcinoma cell line CC-531 was injected into the peritoneal cavity of 80 WAG/Rij rats to induce PC. Animals were randomized into four treatment groups (n = 20): CS only, CS followed by HIPEC (mitomycin 35 mg/m(2) at 41.5°C), CS followed by EPIC during 5 days (i.p. injection of mitomycin on day 1 and 5-fluorouracil on days 2-5), and CS followed by HIPEC plus EPIC. Primary outcome was survival.

RESULTS

In rats treated with CS only, median survival was 53 days (95% confidence interval (CI) 49-57 days). In rats treated with CS followed by HIPEC, survival was significantly (P = 0.001) increased (median survival 94 days, 95% CI 51-137 days). In the group treated with EPIC after CS, 12 out of 20 rats were still alive at the end of the experiment (P < 0.001 as compared with CS only). In the group receiving both treatments, 11 rats died of toxicity, and therefore this group was not included in the survival analysis.

CONCLUSIONS

Both EPIC and HIPEC were effective in prolonging survival. The beneficial effect of EPIC on survival seemed to be more pronounced than that of HIPEC. Further research is indicated to evaluate and compare the possible benefits and adverse effects associated with both treatments.

Distribution of doxorubicin in rats undergoing ultrasonic drug delivery

Ultrasound (US) increases efficacy of drugs delivered from micelles, but the pharmacokinetics have not been studied previously. In this study, US was used to deliver doxorubicin (Dox) sequestered in micelles in an in vivo rat model with bilateral leg tumors. One of two frequencies with identical mechanical index and intensity was delivered for 15 min to one tumor immediately after systemic injection of micellar Dox. Pharmacokinetics in myocardium, liver, skeletal muscle, and tumors were measured for 1 week. When applied in combination with micellar Dox, the ultrasoincated tumor had higher Dox concentrations at 30 min, compared to bilateral noninsonated controls. Initially, concentrations were highest in heart and liver, but within 24 h they decreased significantly. From 24 h to 7 days, concentrations remained highest in tumors, regardless of whether they received US or not. Comparison of insonated and noninsonated tumors showed 50% more Dox in the insonated tumor at 30 min posttreatment. Four weekly treatment produced additional Dox accumulation in the myocardium but not in liver, skeletal leg muscle, or tumors compared to single treatment. Controls showed that neither US nor the empty carrier impacted tumor growth. This study shows that US causes more release of drug at the targeted tumor.

Role of frequency and mechanical index in ultrasonic-enhanced chemotherapy in rats

PURPOSE

The therapeutic effect of ultrasound and micellar-encapsulated doxorubicin was studied in vivo using a tumor-bearing rat model with emphasis on how tumor growth rate is affected by ultrasonic parameters such as frequency and intensity.

METHODS

This study employed ultrasound of two different frequencies (20, 476 kHz) and two pulse intensities, but identical mechanical indices and temporal average intensities. Ultrasound was applied weekly for 15 min to one of two bilateral leg tumors (DHD/K12/TRb colorectal epithelial cell line) in the rat model immediately after intravenous injection of micelle-encapsulated doxorubicin. This therapy was applied weekly for 6 weeks.

RESULTS

Results showed that tumors treated with drug and ultrasound displayed, on average, slower growth rates than non-insonated tumors (P = 0.0047). However, comparison between tumors that received 20 or 476-kHz ultrasound treatments showed no statistical difference (P = 0.9275) in tumor growth rate.

CONCLUSION

Application of ultrasound in combination with drug therapy was effective in reducing tumor growth rate, irrespective of which frequency was employed.

[Bladder perforation during transurethral resection of bladder tumour: a review]

Transurethral resection of bladder tumour is a common procedure (10,711 new cases of bladder tumour diagnosed in France in 2000), associated with a certain morbidity. Intra- or extraperitoneal perforation of the bladder wall is a possible complication. The diagnosis is generally established intraoperatively and cystography can be performed in the operating room to demonstrate the diameter of the perforation. Most cases of extraperitoneal perforation can be treated conservatively by simple bladder drainage. Intraperitoneal perforations may require surgical repair Laparoscopy is currently tending to replace open surgery for this repair. One of the risks of perforation is also tumour seeding outside of the bladder However metastases related to perforation appear to be rare and occur rapidly requiring close surveillance.

Recurrence of gastric cancer in the jejunal pouch after completion gastrectomy

We herein present a case of recurrence of gastric cancer in the jejunal pouch after total gastrectomy in a 74-year-old man. He had a history of two operations for gastric cancer. The second operation was a completion gastrectomy with jejunal pouch reconstruction and regional lymphadenectomy, for gastric cancer in the cardia of the remnant stomach, performed 2 years and 9 months before the present admission. A follow-up endoscopy showed three elevated tumors along the suture lines in the jejunal pouch in the upper digestive tract. Resection of the jejunal pouch was performed. Gross pathological examination revealed elevated lesions along the staple suture lines in the jejunal pouch. Histopathologically, moderately differentiated tubular adenocarcinoma involving the muscular layer, without lymphatic metastases, was recognized. Recurrence of gastric cancer in the jejunal pouch after resection is rare. We suggest that implantation of exfoliated cancer cells gave rise to the recurrence of tumors on the suture line in this patient. We also review two cases of gastric cancer in the jejunal pouch after resection previously described in the literature.

Timing of adjuvant radioimmunotherapy after cytoreductive surgery in experimental peritoneal carcinomatosis of colorectal origin

BACKGROUND

Treatment of patients with peritoneal carcinomatosis (PC) of colorectal cancer (CRC) includes cytoreductive surgery (CS) in combination with (hyperthermic) intraperitoneal chemotherapy (HIPEC), resulting in a limited survival benefit with high morbidity and mortality rates. Radioimmunotherapy (RIT) as adjuvant therapy after CS of CRC has been shown to prolong survival in preclinical studies. However, the optimal setting of RIT remains to be determined.

METHODS

PC was induced by intraperitoneal inoculation of CC-531 colon carcinoma cells in Wag/Rij rats. Animals were subjected to exploratory laparotomy (Sham), CS only or CS + RIT at different time points after surgery. RIT consisted of 55 MBq lutetium-177-labelled anti-CC531 antibody MG1 (183 mug). The primary endpoint was survival.

RESULTS

Cytoreductive surgery with or without RIT was well tolerated. Median survival of animals in the Sham and CS group was 29 days and 39 days, respectively (P < 0.04). Compared to CS alone, median survival of rats after adjuvant RIT was 77 days (P < 0.0001), 52 days (P < 0.0001) and 45 days (P < 0.0001) when given directly, 4 and 14 days after surgery, respectively.

CONCLUSION

The efficacy of adjuvant RIT after CS for the treatment of PC of colonic origin decreases when the administration of the radiolabelled MAbs is postponed. This study shows that adjuvant RIT should be given as early as possible after surgery.

DOES THE MANAGEMENT OF BLADDER PERFORATION DURING TRANSURETHRAL RESECTION OF SUPERFICIAL BLADDER TUMORS PREDISPOSE TO EXTRAVESICAL TUMOR RECURRENCE?

PURPOSE

We evaluated the impact of a bladder perforation during transurethral resection of superficial bladder tumor on extravesical tumor recurrence and patient prognosis. We also defined potential risk factors for extravesical recurrence prospectively giving emphasis to the management of the perforation.

MATERIALS AND METHODS

The medical records of 3,410 patients were reviewed. Parameters recorded included patient age and sex, tumor stage, grade, number, size and location at the time of perforation, the type of bladder perforation (extraperitoneal vs intraperitoneal) and the way the perforation was managed (open surgical repair vs conservative treatment). Logistic regression analysis was used to identify risk factors for extravesical recurrence. Cox regression analysis was used to compare cancer specific survival.

RESULTS

A total of 34 cases of bladder perforation were recorded, 4 patients were treated with open surgery and 30 treated conservatively. The 4 patients who underwent open surgery presented with extravesical recurrence after a mean followup of 7.5 months. The remaining 30 patients had no evidence of extravesical recurrence after a mean followup of 60 months (p <0.001). Of the patients with extravesical relapse 3 died of disease. The surgical management of bladder perforation was the best predictor of extravesical recurrence (p <0.001, r = 1.13), followed by an intraperitoneal localization of the perforation (p =0.0003, r = 0.67) and tumor size (p =0.01, r = 0.42).

CONCLUSIONS

Surgical repair of a bladder perforation during transurethral resection of bladder tumor increases the risk of extravesical tumor cell recurrence and negatively affects patient prognosis.

Port site metastases

BACKGROUND

Concerns about port site metastases have limited the application of minimally invasive surgery for intra-abdominal malignancies. The purpose of this review article was to summarize the current literature regarding port site metastases.

METHODS

A Medline search identified >100 articles in English published during the last 15 years regarding the history, incidence, etiology, and prevention of port site metastases. These articles were reviewed and are summarized.

RESULTS

The incidence of port site metastases, initially thought to be as high as 21%, is now thought to be closer to the incidence of wound metastases after open surgery. Multiple etiologic factors have been studied including direct wound contamination, surgical technique, effects of carbon dioxide pneumoperitoneum, and changes in host immune response. Various preventive measures have been proposed.

CONCLUSIONS

Port site metastases are a well-documented and devastating complication after laparoscopic resection of intra-abdominal malignancies. Although the etiology is not yet understood, a number of factors are contributory. All efforts should be made to prevent port site metastases.

Laparoscopic colon resection for colon cancer

INTRODUCTION

Laparoscopic colon resection for cancer is as yet an unproven operation. This review article summarizes current data on the topic.

METHODS

A Medline review identified articles published since 1990 summarizing patients with potentially curable colon cancer who underwent a laparoscopic-assisted colon resection. Only articles that were randomized or had a control group with historical or matched open cases were used.

RESULTS

Very few prospective randomized controls exist. Several clinical trials are under way with one completed. Data thus far support some patient benefits with a laparoscopic approach. No differences in morbidity, oncologic data, or survival appear to exist.

CONCLUSIONS

The results of ongoing clinical trials are still needed to further evaluate the role of laparoscopic assisted colon resection in patients with potentially curable colon cancer.

The rationale of perioperative intraperitoneal chemotherapy in the treatment of peritoneal surface malignancies

In summary, the use of perioperative intraperitoneal chemotherapy is a rational and scientifically sound treatment option for patients with peritoneal carcinomatosis. By delivering chemotherapeutic agents directly into the peritoneal cavity in the perioperative period, after cytoreductive procedures resulting in minimal residual tumor load, the cytotoxicity, efficacy, and safety of these agents can be maximized. The use of this treatment strategy in the intraoperative or perioperative period ensures that the efficacy of the chemotherapeutic agents is not reduced by limitations of abdominal compartmentalization and scarring. Treating patients under hyperthermic conditions may confer an additional benefit. Although the use of perioperative chemotherapy or hyperthermic intraperitoneal chemotherapy is not yet part of the standard of care for the treatment of advanced abdominal malignancies, both basic science and clinical investigations have confirmed the validity of these regimens. Further clinical studies in a cooperative group setting are necessary to prove the efficacy of perioperative intraperitoneal chemotherapy in both the treatment and prevention of peritoneal surface malignancy.

Intérêt des lavages abdominaux pour la prévention de l’ensemencement néoplasique péritonéal

Spontaneous or iatrogenous peritoneal seeding is responsible for locoregional recurrent cancer or peritoneal carcinomatosis. Few surgeons are used to wash the abdominal cavity to prevent peritoneal seeding. But experimentally, washing is not able to dislodge or destroy tumour cells adherent to the peritoneum or to the surgical wounds. The antitumoral effect of abdominal washing is increased by addition of antiseptics or anti-adherent agents.

Impact of perioperative intraperitoneal chemotherapy on the treatment of primary gastric cancer

Perioperative intraperitoneal chemotherapy provides effective prevention of peritoneal recurrence after resection in advanced gastric cancer, especially in gastric cancer with serosal invasion. With improved local-regional control, improved survival rate for advanced gastric cancer is achieved. This type of regional chemotherapy is an independent treatment-related prognostic factor for advanced gastric cancer. There are several methods of perioperative intraperitoneal chemotherapy. Among them, early postoperative intraperitoneal chemotherapy is simple and easy to perform.

An orthotopic nude mouse model for evaluating pathophysiology and therapy of pancreatic cancer

INTRODUCTION

Orthotopic, clinically relevant animal models are necessary for the study of pathophysiology and therapy for pancreatic cancer.

AIMS

To develop a minimally traumatic technique of orthotopic tumor induction, to develop a scoring system to quantify local and systemic tumor spread, and to provide a model with a broad range of well-differentiated to undifferentiated pancreatic cancers.

METHODOLOGY

Orthotopic tumors were induced in nude mice by atraumatic pancreatic implantation of two fragments from subcutaneous donor tumors or intrapancreatic injection of human tumor cells (MIAPaCa-2, AsPC-1, HPAF-2, Capan-1). Animals were monitored for 14 weeks or until death. Primary tumor volume, local infiltration, and systemic metastasis were assessed and analyzed at autopsy. Macroscopic findings were confirmed by histologic evaluation.

RESULTS

Tumor take rate in the implantation group was 100% for all four cell lines. Marked differences with regard to tumor size, metastatic spread, and survival were found depending on the grade of differentiation. Less differentiated cells (MIAPaCa-2, AsPC-1) caused higher dissemination scores and mortality than better-differentiated cells (HPAF-2, Capan-1). Clinical features included cachexia, jaundice, and malignant ascites. Orthotopic tumor cell injection resulted in an incomplete tumor take rate. Moreover, early artificial abdominal tumor spread was found in injected animals due to microscopic cell loss during the injection procedure.

CONCLUSIONS

Orthotopic implantation of donor tumor fragments into nude mice is technically feasible and is superior to the cell injection technique. It results in reproducible local and systemic development of pancreatic cancer that mimics the human disease. A dissemination score may help to better quantify therapeutic effects in future studies.

New responsibilities in the management of colorectal cancer with peritoneal seeding

The initial dissemination of colon cancer through three routes: the lymphatics, the portal blood, and the peritoneal surfaces. Dissemination to periotoneal surface may be only superficial contamination of the parietal and visceral peritoneum that may be treatable for cure. Unfortunately, surgery may have an adverse impact on peritoneal surface dissemination. Surgical interventions may convert a superficial process into an invasive condition with a greatly reduced prognosis. In patients with peritoneal seedings, peritonectomy procedures and perioperative intraperitoneal chemotherapy should be performed concomitantly. By use of a quantitative scoring system, the mass of cancer present in the abdomen and pelvis at the time of treatment of carcinomatosis correlated directly with survival. Aggressive treatment of patients with peritoneal carcinomatosis requires consideration in the management of colorectal cancer.

Effects of Doxorubicin (Adriamycin) and [(+)-1,2-bis(3,5-dioxopiperazinyl-1-yl)]propane (ICRF-187) on skeletal muscle protease activities

Adverse effects of doxorubicin (adriamycin) have been reported to be due to iron-catalyzed free radical formation, which can be prevented with the cytoprotective chelating agent [(+)-1,2-bis(3,5-dioxopiperazinyl-1-yl)]propane (dexrazoxane; ICRF-187). Affected tissues include the heart, gastrointestinal tract, and kidney. However, there is very little information on the effects of adriamycin on skeletal muscle, despite the fact that there is direct and indirect evidence to show that both adriamycin and ICRF-187 are myotoxic. To investigate the mechanisms of cytotoxicity of these agents in skeletal muscle, we have conducted a systematic investigation of the activities of the major lysosomal (dipeptidyl aminopeptidase I and II and cathepsins B, D, H, and L) and cytoplasmic (alanyl-, arginyl-, and leucyl aminopeptidase, dipeptidyl aminopeptidase IV, tripeptidyl aminopeptidase, and proline endopeptidase) muscle proteases. These enzymes play an important role in normal cellular function and represent potential targets for toxic and protective agents. Male Wistar rats (approx. 0.2 kg) were subjected to a pretreatment phase of 30 min followed by a treatment stage of either 2.5 or 24 h. The pretreatment involved injection of a single bolus of either saline (0.15 mol/l NaCl; 5 ml/kg ip) or ICRF-187 (100 mg/kg; 5 ml/kg ip). After 30 min, rats were injected again with a single bolus of either adriamycin (5 mg/kg; 10 ml/kg ip) or saline (0.15 mol/l NaCl; 10 ml/kg ip) in the treatment phase. At either 2.5 or 24 h after the last adriamycin or saline injection, rats were killed for subsequent dissection of the gastrocnemius muscle for analysis. In the 2.5-h study, there were significant reductions in cathepsin D activities of adriamycin-treated rats compared to saline injected control (p = 0.02). In both 2.5- and 24-h studies there were also significant differences (p = 0.05) in cathepsin H activities between rats treated with adriamycin and ICRF-187, although these differences were not significant when data were compared with corresponding saline-injected rats. There were no other overt effects for any of the other proteases at either 2.5 or 24 h. We conclude that both adriamycin and ICRF-187 have very little effect on the activities of muscle proteases and that altered proteolysis is not involved in the reported pathological reactions induced by these agents.

Early postoperative intraperitoneal chemotherapy with mitomycin C, 5-fluorouracil and cisplatin for advanced gastric cancer

OBJECTIVE

The long-term survival of patients who undergo surgery for stage IV gastric cancer is poor, due to metastatic spread of the tumor. Intraperitoneal chemotherapy (IPT) as a possible treatment for peritoneal dissemination has been investigated in a number of different tumors. The aim of this study was to investigate the toxicity and impact of early postoperative IPT on the survival of patients with advanced gastric cancer.

METHODS

Between 1993 and 1997, a total of 91 patients with stage IV gastric cancer who underwent potentially curative or palliative resection received intraperitoneal mitomycin C before closure of the abdominal wound. 5-Fluorouracil and cisplatin were administered intraperitoneally on postoperative days 1-4, and this was repeated at 4-week intervals.

RESULTS

All patients received a median of 3 IPT perfusions. There were 24 (26.4%) postoperative complications and 1 (1.1%) mortality. The most frequent hematologic toxicity (grade 3-4) was leukopenia. The major nonhematologic toxicities (grade 3-4) were emesis and nephrotoxicity. After a median follow-up period of 26 months, 14 patients remain alive without evidence of recurrence, whereas 75 patients died due to recurrence or progression of disease. The median survival period for all 91 patients was 15.4 months. When survival according to the residual tumor was analyzed, median survival was 36.0 months in the R0 (curative resection) group, 20.6 months in the R1 group (margins of resected specimens showing microscopic residual tumor or diameter of each residual tumor less than 3 mm) and 9.0 months in the R2 group (macroscopic residual tumor larger than 3 mm) (p < 0.001).

CONCLUSIONS

IPT was found to be safe, and it appears to improve the prognosis in patients with minimal residual tumors. However, complete cytoreductive surgery is mandatory for achieving the beneficial effect of IPT.

An improved clinical model of orthotopic pancreatic cancer in immunocompetent Lewis rats

The study of pancreatic cancer (PaCa) requires orthotopic, clinically relevant animal models. The aims of this study were to establish an orthotopic model of ductal pancreatic adenocarcinoma in immunocompetent Lewis rats and to develop a scoring system to quantify local tumor infiltration and distant metastasis. Cells (10(7)) of the rat ductal PaCa cell line DSL-6A/C1 were injected s.c. into donor rats. After 8 weeks, either three (IPL-3) or five (IPL-5) fragments (1 mm3) of the resulting s.c. tumors were microsurgically implanted into the pancreas of recipient rats. In another series of animals, 10(7) DSL-6A/C1 cells were directly injected (INJ) into the pancreas. All animals were monitored daily until death or for 16 weeks. At autopsy, volume of primary tumors and ascites, local and systemic tumor spread, and histologic phenotype were assessed. IPL-5 resulted in significantly larger tumors (12,224 +/- 1,933 mm3), more local infiltration and systemic spread (score: 18.3 +/- 2.0 points), severe clinical tumor disease, and lethality (50%) in comparison to the other induction techniques (IPL-3: 283 +/- 115 mm3/3.5 +/- 0.8 points/0; INJ: 752 +/- 207 mm3/4.3 +/- 0.8 points/8%). Histologic examination revealed moderately to well-differentiated ductal tumors, surrounded by dense stroma. Intraperitoneal tumor dissemination in the INJ group occurred simultaneous with primary tumor growth, indicating PaCa cell spread during injection. Orthotopic implantation of five DSL-6A/C1 tumor fragments into the rat pancreas provides a valid clinical model of ductal pancreatic adenocarcinoma in immunocompetent rodents for preclinical treatment studies. The dissemination score we used permitted quantification of local and systemic tumor spread.

Changes of the coagulation and fibrinolysis system in malignancy: their possible impact on future diagnostic and therapeutic procedures

The interaction between malignant cell growth and the coagulation and fibrinolysis system has been a well known phenomenon for decades. During recent years, this area of research has received new attention. Experimental data suggest a role for the coagulation and fibrinolysis system in tumor development, progression and metastasis. Also, clinical research suggests that targeting the coagulation system or fibrinolysis system might influence the course of malignant disease beneficially. This paper reviews data on various hemostatic and fibrinolytic parameters in malignancy; the possible use of such parameters as risk markers in oncology patients; and possible targets of anti-neoplastic therapies using anticoagulant and/or antifibrinolytic strategies. Current evidence suggests that the tissue factor/factor VIIa pathway mediates the most abundant procoagulant stimulus in malignancy via the increase in thrombin generation. Tissue factor has been suggested to mediate pro-metastatic properties via coagulation-dependent and coagulation-independent pathways; tissue factor has also been implicated in tumor neo-angiogenesis. However, so far no model has been validated that would allow the use of tissue factor in its soluble or insoluble form as a marker for risk stratification in tumor patients. On the other hand, there is now good evidence that parts of the fibrinolytic system, such as urokinase-type plasminogen activator and its receptor ("uPAR"), can be used as strong predictors of outcome in several types of cancer, specifically breast cancer. Observation of various treatment options in patients with thromboembolic disease and cancer as well as attempts to use anticoagulants and/or therapies modulating the fibrinolytic system as anti-neoplastic treatment strategies have yielded exciting results. These data indicate that anticoagulant therapy, and specifically low molecular weight heparin therapy, is likely to have anti-neoplastic effects; and that their use in addition to chemotherapy will probably improve outcome of tumor treatment in certain types of cancer. However, the body of clinical data is still relatively small and the question whether or not we should routinely consider the coagulation and/or fibrinolysis system as therapeutic targets in cancer patients is yet to be answered.

Adjuvant intraperitoneal 5-fluorouracil in high-risk colon cancer: A multicenter phase III trial

OBJECTIVE

To evaluate the results of a prospective multicenter randomized study of adjuvant intraperitoneal 5-fluorouracil (5-FU) administered during 6 days shortly after resection of stages II and III colon cancers.

SUMMARY BACKGROUND DATA

Systemic adjuvant chemotherapy improves the survival of patients with stage III colon cancer receiving treatment for 6 months. Intraperitoneal chemotherapy theoretically combines peritoneal and hepatic effects.

METHODS

After resection, 267 patients were randomized into two groups. Patients in group 1 (n = 133) underwent resection followed by intraperitoneal administration of 5-FU (0.6 g/m2/day) for 6 days (day 4 to day 10). These patients also received intravenous 5-FU (1 g) during surgery. Patients in group 2 underwent resection alone (n = 134).

RESULTS

In group 1, 103 patients received the total dose, 18 received a partial dose as a result of technical or tolerance problems, and 12 did not receive the chemotherapy. Rates of surgical death and complications were similar in both groups. Tolerance to treatment was excellent or fair in 97% of the patients and poor in 3%. After a median follow-up of 58 months, 5-year overall survival rates were 74% in group 1 and 69% in group 2; disease-free survival rates were 68% and 62%, respectively. Survival curves were superimposed until 3 years after treatment and began diverging thereafter. Among patients receiving the full treatment, the 5-year disease-free survival rate was improved in the treatment group in patients with stage II cancers but was unchanged in patients with stage III cancers.

CONCLUSIONS

Chemotherapy with intraperitoneal 5-FU administered during a short period after surgery was well tolerated but was not sufficient to reduce the risk of death significantly. However, it reduced the risk of recurrence in stage II cancers. These results suggest that it should be associated with systemic chemotherapy to reduce both local and distant recurrences.

Influence of cytotoxic agents on intraperitoneal tumor implantation after laparoscopy

PURPOSE

Recent experimental studies suggest that laparoscopic surgery for abdominal malignancy may be associated with increased tumor implantation. This study investigated the influence of cytotoxic agents (administered intraperitoneally or intramuscularly) on implantation of a tumor cell suspension after laparoscopic surgery in an experimental model.

METHODS

Thirty-three Dark Agouti rats underwent laparoscopy with CO2 insufflation and instillation of a tumor cell suspension into the abdominal cavity. Rats were randomly allocated to one of the following study groups (9 rats in the control group, 6 rats in all other groups): 1) control (no intraperitoneal instillation); 2) intraperitoneal normal saline (0.9 percent); 3) intraperitoneal povidone-iodine (Betadine to normal saline 1:10 dilution); 4) intraperitoneal methotrexate (2 doses of 0.125 mg/kg body weight in normal saline administered 24 hours apart); 5) intramuscular injection of 2 doses of 0.125 mg/kg body weight administered 24 hours apart (no intraperitoneal agent). Rats were killed 7 days after the procedure, and the peritoneal cavity and port sites were examined for the presence of tumor.

RESULTS

A significant reduction in tumor implantation and port-site metastases was observed in all treatment groups (povidone-iodine and intramuscular and intraperitoneal methotrexate).

CONCLUSIONS

This study suggests that tumor implantation after laparoscopic surgery and port-site metastases might be prevented by the intraperitoneal or systemic administration of cytotoxic agents. Further studies are needed to determine whether these findings can be applied to clinical practice.

Prospective randomized trial of early postoperative intraperitoneal chemotherapy as an adjuvant to resectable gastric cancer

OBJECTIVE

Surgeons have postulated on numerous occasions that cancer resection may participate in the dissemination of a malignancy. This randomized trial sought to determine whether a large volume of chemotherapy solution used perioperatively to flood the peritoneal cavity could eliminate microscopic residual disease and thereby improve survival of patients with gastric cancer.

SUMMARY BACKGROUND DATA

Surgical treatment failures in patients with gastric cancer are confined to the abdomen in most patients. Resection site and peritoneal surface spread, along with liver metastases, are the most common areas of recurrence. Survival and quality of life of patients with gastric cancer would be improved if disease progression at these anatomic sites was reduced.

METHODS

In a prospective randomized trial of 248 patients, intraperitoneal mitomycin C on day 1 and intraperitoneal 5-fluorouracil on days 2 through 5 were administered after gastric cancer resection. Patients who were thought to have stage II or stage III disease were randomized after resection to surgery alone versus surgery plus early postoperative intraperitoneal chemotherapy. After final pathologic examinations, there were 39 patients with stage I, 50 with stage II 95 with stage III, and 64 with resected stage IV cancer.

RESULTS

The 5-year survival of the surgery-only group was 29.3%, and the surgery-plus-intraperitoneal chemotherapy group was 38.7% (p = 0.219). In a subset analysis, the patients with stage I, stage II, and stage IV disease showed no statistically significant difference in survival. The 5-year survival rate of patients with stage III disease who underwent surgery only was 18.4% versus a survival rate of 49.1% for patients who underwent surgery plus intraperitoneal chemotherapy (p = 0.011).

CONCLUSIONS

In a subset analysis, patients with stage III gastric cancer have shown a statistically significant improvement in survival when treated with perioperative intraperitoneal chemotherapy. Further studies in patients with gastric cancer with surgically directed chemotherapy are suggested.

Port-site metastases following laparoscopic surgery

BACKGROUND

Application of laparoscopy to the resection of malignancy has been followed by a literature describing cases of metastatic involvement at laparoscopic port sites. These include patients who underwent surgery for early stage carcinoma and instances following laparoscopic procedures during which tumours were not dissected.

METHODS

Recently published clinical and experimental studies, and case reports related to this problem are reviewed; their relevance is discussed.

RESULTS

Experimental studies incorporating bench top and large animal models have confirmed that tumour cells may be redistributed to port sites during laparoscopic surgery either directly from contaminated instruments or indirectly via the insufflation gas. Small animal models suggest that the incidence of wound metastasis is increased following conventional laparoscopic surgery, and that it may be decreased by gasless laparoscopy or helium insufflation. This evidence suggests that the development of port-site metastases depends not only on the physical redistribution of tumour cells but also on the specific insufflation gas used, possibly because of influences on local metabolic or immune factors acting at the wound site.

CONCLUSION

Further research in this area is urgent. Until the issue is better understood, patients undergoing laparoscopic surgery for malignancy should be entered into clinical trials.