Influence of CO2 pneumoperitoneum during laparoscopic surgery on cancer cell growth

Effects of CO2 pneumoperitoneum on proliferation, apoptosis, and migration of gastrointestinal stromal tumor cells

BACKGROUND

The purpose of the study was to investigate the proliferation and migration capability of human gastrointestinal stromal tumor line GIST-T1 after exposure to different pressures and times of CO₂ pneumoperitoneum.

METHODS

We established simulated CO₂ pneumoperitoneum environment in vitro and divided the human GIST cell GIST-T1 into open control group, 8 mmHg CO₂ pneumoperitoneum treatment group and 15 mmHg CO₂ pneumoperitoneum treatment group. Each group was divided into two subgroups respectively cultured for 1 h and 3 h. pH value of cell culture, cell growth curve, and cell cycle distribution of each group was measured. By application of scratch healing tests and Transwell chamber experiments, mobility ratio and number of cells through 8 µm membranes were measured to assess the migration ability of cells in each group after intervention.

RESULTS

Cell culture pH value of each subgroup in CO₂ group decreased significantly after exposed in CO₂ pneumoperitoneum (P < 0.01). The proliferation of GIST-T1 cells in 15 mmHg CO₂ group was significantly inhibited early (1-2 days) (P < 0.05) and the proliferation of GIST-T1 cells in 8 mmHg CO₂ 1 h subgroup and 15 mmHg CO₂ 1 h subgroup was increased significantly late (4-6 days) (P < 0.05) after the interventions of CO₂ pneumoperitoneum. The percentage of cells in G0-G1 phase increased, the percentage of S phase cells decreased (P < 0.01) in 1-h subgroup and 3-h subgroup of 15 mmHg CO₂ group 24 h after exposure to CO₂. The percentage of cells in S phase increased in 1-h subgroup of 8 mmHg CO₂ group and decreased in 3-h subgroup of 15 mmHg CO₂ group 72 h after exposure to CO₂. In the Transwell chamber experiment, the cell number through 8-µm membrane increased significantly (P < 0.01) in 3-h subgroup of CO₂ group compared to that in 3-h subgroup of control group.

CONCLUSIONS

The routine pressure and duration of CO₂ pneumoperitoneum used in clinic did not promote the proliferation of gastrointestinal stromal tumors, but had a potential risk of increasing postoperative recurrence and distant metastasis.

A minimally invasive approach for peritonectomy procedures and hyperthermic intraperitoneal chemotherapy (HIPEC) in limited peritoneal carcinomatosis: The American Society of Peritoneal Surface Malignancies (ASPSM) multi-institution analysis

BACKGROUND

Minimally invasive surgery is playing an increasing role in the treatment of patients with gastrointestinal and gynaecological malignancies as the data show reduced morbidity, faster recovery and similar oncological outcome when compared to open procedures.

MATERIALS AND METHODS

The American Society of Peritoneal Surface Malignancies (ASPSM) conducted a retrospective study to analyse peritonectomy procedures and HIPEC done via the laparoscopic route. A database with standard clinical and pathological parameters was set up and distributed amongst ASPSM members. Rate of relapse, morbidity and mortality were the primary endpoints of the study.

RESULTS

A total of 90 patients from 7 centres around the world were identified. Sixty percent were female. Mean age was 50 years. Peritoneal carcinomatosis from appendiceal origin was the most common diagnosis in a 64.9% of patients and colon origin was diagnosed in 16.5% of patients. Mean peritoneal cancer index (PCI) was 4.1 (0-10). Forty-one percent of patients had a bowel resection. Mean operative time was 4.7 h (2.5-8). All patients had a complete cytoreduction and HIPEC. Grade 3 and 4 morbidity was 3.0 and 6.5%, respectively. The most common reason for re-operation was an internal hernia in 2 out of 5 cases. Operative mortality and re-admission rates were 0 and 5%, respectively. Mean hospital stay was 7.4 days (1-18). At a mean follow-up of 31.6 months, 15/90 patients have a disease relapse but loco-regional relapse was identified in only five patients.

CONCLUSIONS

Analysis of these data suggests that minimally invasive approach for peritonectomy procedures and HIPEC is feasible, safe and should be considered as part of the armamentarium for highly selected patients with peritoneal surface malignancies with limited tumour burden, defined as PCI of 10 or less and borderline tumours as low-grade pseudomyxoma and benign multicystic mesothelioma.

Transcutaneous application of carbon dioxide (CO2) induces mitochondrial apoptosis in human malignant fibrous histiocytoma in vivo

Mitochondria play an essential role in cellular energy metabolism and apoptosis. Previous studies have demonstrated that decreased mitochondrial biogenesis is associated with cancer progression. In mitochondrial biogenesis, peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) regulates the activities of multiple nuclear receptors and transcription factors involved in mitochondrial proliferation. Previously, we showed that overexpression of PGC-1α leads to mitochondrial proliferation and induces apoptosis in human malignant fibrous histiocytoma (MFH) cells in vitro. We also demonstrated that transcutaneous application of carbon dioxide (CO₂) to rat skeletal muscle induces PGC-1α expression and causes an increase in mitochondrial proliferation. In this study, we utilized a murine model of human MFH to determine the effect of transcutaneous CO₂ exposure on PGC-1α expression, mitochondrial proliferation and cellular apoptosis. PGC-1α expression was evaluated by quantitative real-time PCR, while mitochondrial proliferation was assessed by immunofluorescence staining and the relative copy number of mitochondrial DNA (mtDNA) was assessed by real-time PCR. Immunofluorescence staining and DNA fragmentation assays were used to examine mitochondrial apoptosis. We also evaluated the expression of mitochondrial apoptosis related proteins, such as caspases, cytochorome c and Bax, by immunoblot analysis. We show that transcutaneous application of CO₂ induces PGC-1α expression, and increases mitochondrial proliferation and apoptosis of tumor cells, significantly reducing tumor volume. Proteins involved in the mitochondrial apoptotic cascade, including caspase 3 and caspase 9, were elevated in CO₂ treated tumors compared to control. We also observed an enrichment of cytochrome c in the cytoplasmic fraction and Bax protein in the mitochondrial fraction of CO₂ treated tumors, highlighting the involvement of mitochondria in apoptosis. These data indicate that transcutaneous application of CO₂ may represent a novel therapeutic tool in the treatment of human MFH.

A computerized tomography scan method for calculating the hernia sac and abdominal cavity volume in complex large incisional hernia with loss of domain

Preoperative progressive pneumoperitoneum (PPP) is a safe and effective procedure in the treatment of large incisional hernia (size > 10 cm in width or length) with loss of domain (LIHLD). There is no consensus in the literature on the amount of gas that must be insufflated in a PPP program or even how long it should be maintained. We describe a technique for calculating the hernia sac volume (HSV) and abdominal cavity volume (ACV) based on abdominal computerized tomography (ACT) scanning that eliminates the need for subjective criteria for inclusion in a PPP program and shows the amount of gas that must be insufflated into the abdominal cavity in the PPP program. Our technique is indicated for all patients with large or recurrent incisional hernias evaluated by a senior surgeon with suspected LIHLD. We reviewed our experience from 2001 to 2008 of 23 consecutive hernia surgical procedures of LIHLD undergoing preoperative evaluation with CT scanning and PPP. An ACT was required in all patients with suspected LIHLD in order to determine HSV and ACV. The PPP was performed only if the volume ratio HSV/ACV (VR = HSV/ACV) was >or=25% (VR >or= 25%). We have performed this procedure on 23 patients, with a mean age of 55.6 years (range 31-83). There were 16 women and 7 men with an average age of 55.6 years (range 31-83), and a mean BMI of 38.5 kg/m(2) (range 23-55.2). Almost all patients (21 of 23 patients-91.30%) were overweight; 43.5% (10 patients) were severely obese (obese class III). The mean calculated volumes for ACV and HSV were 9,410 ml (range 6,060-19,230 ml) and 4,500 ml (range 1,850-6,600 ml), respectively. The PPP is performed by permanent catheter placed in a minor surgical procedure. The total amount of CO(2) insufflated ranged from 2,000 to 7,000 ml (mean 4,000 ml). Patients required a mean of 10 PPP sessions (range 4-18) to achieve the desired volume of gas (that is the same volume that was calculated for the hernia sac). Since PPP sessions were performed once a day, 4-18 days were needed for preoperative preparation with PPP. The mean VR was 36% (ranged from 26 to 73%). We conclude that ACT provides objective data for volume calculation of both hernia sac and abdominal cavity and also for estimation of the volume of gas that should be insufflated into the abdominal cavity in PPP.

Laparoscopic versus open left lateral segmentectomy

BACKGROUND

Laparoscopic liver surgery is becoming increasingly common. This cohort study was designed to directly compare perioperative outcomes of the left lateral segmentectomy via laparoscopic and open approach.

METHODS

Between 2002 and 2006 43 left lateral segmentectomies were performed at King's College Hospital. Those excluded from analysis included previous liver resections, polycystic liver disease, liver cirrhosis and synchronous operations. Of 20 patients analysed, laparoscopic (n = 10) were compared with open left lateral segmentectomy (n = 10). Both groups had similar patient characteristics.

RESULTS

Morbidity rates were similar with no wound or chest infection in either group. The conversion rate was 10% (1/10). There was no difference in operating time between the groups (median time 220 minutes versus 179 minutes, p = 0.315). Surgical margins for all lesions were clear. Less postoperative opiate analgesics were required in the laparoscopic group (median 2 days versus 5 days, p = 0.005). The median postoperative in-hospital stay was less in the laparoscopic group (6 days vs 9 days, p = 0.005). There was no mortality.

CONCLUSION

Laparoscopic left lateral segmentectomy is safe and feasible. Laparoscopic patients may benefit from requiring less postoperative opiate analgesia and a shorter post-operative in-hospital stay.

Effects of HIF-1alpha on human gastric cancer cell apoptosis at different CO(2) pressures

The effects and potential molecular mechanisms underlying carbon dioxide (CO(2)) pneumoperitoneum on gastric cancer cell apoptosis are not fully understood. In this study, we assessed the effects of CO(2) pneumoperitoneum on the apoptosis of MKN-45 gastric cancer cells. Additionally, we investigated the role of HIF-1alpha in CO(2) pneumoperitoneum-induced apoptosis of gastric cancer cells. MKN-45 cells were cultured in CO(2) or air pneumoperitoneum at 0, 12 and 15 mmHg pressures for 4 h. We observed a change in cells morphology and increasing apoptotic ratios in MKN-45 cells when they were put into a 15 mmHg CO(2) pneumoperitoneum environment. However, there was no significant difference between the 0, 12 mmHg CO(2) pneumoperitoneum and the control groups. Exposure to 15 mmHg CO(2) pneumoperitoneum significantly enhanced the expression levels of HIF-1alpha and Bax, while it attenuated Bcl-2 expression levels. When we inhibited HIF-1alpha by small interfering RNA (siRNA), we found that the apoptotic ratio of MKN-45 cells decreased in 15 mmHg CO(2) pneumoperitoneum. This treatment markedly elevated Bcl-2 levels and decreased Bax expression. These data suggest that CO(2) pneumoperitoneum may accelerate the apoptosis of MKN-45 cells at higher pressures. HIF-1alpha is a crucial factor that affects gastric cancer cell apoptosis by downregulating the Bcl-2/Bax ratio.

Laparoscopic liver resection assisted by the laparoscopic Habib Sealer

BACKGROUND

Radiofrequency has been used as a tool for liver resection since 2002. A new laparoscopic device is reported in this article that assists liver resection laparoscopically.

METHODS

From October 2006 to the present, patients suitable for liver resection were assessed carefully for laparoscopic resection with the laparoscopic Habib Sealer (LHS). Detailed data of patients resected laparoscopically with this device were collected prospectively and analyzed.

RESULTS

In all, 28 patients underwent attempted laparoscopic liver resection. Four cases had to be converted to an open approach because of extensive adhesions from previous colonic operations. Twenty-four patients completed the procedure comprising tumorectomy (n = 7), multiple tumoretcomies (n = 5), segmentectomy (n = 3), and bisegmentectomies (n = 9). Vascular clamping of portal triads was not used. The mean resection time was 60 +/- 23 min (mean +/- SD), and blood loss was 48 +/- 54 mL. None of the patients received any transfusion of blood or blood products perioperatively or postoperatively. Postoperatively, 1 patient developed severe exacerbation of asthma that required steroid therapy, and 1 other patient had a transient episode of liver failure that required supportive care. The mean duration of hospital stay was 5.6 +/- 2 days (mean +/- SD). At a short-term follow up, no recurrence was detected in patients with liver cancer.

CONCLUSION

Laparoscopic liver resection can be performed safely with this new laparoscopic liver resection device with a significantly low risk of intraoperative bleeding or postoperative complications.

The current role of laparoscopic liver resection for the treatment of liver tumors

Laparoscopic liver resection (LLR) represents a natural extension of minimally invasive surgery. Several case-control studies have demonstrated that LLR is safe and feasible in carefully selected patients. LLR is associated with reduced operative blood loss and earlier recovery when compared with open surgery. In addition, oncologic clearance achieved with LLR is comparable to that achieved with open surgery. Improved cosmesis and postoperative patient comfort also argue in favor of LLR compared with open surgery. When considering whether a patient is suitable for LLR, the size and location of the neoplasm must be taken into account. Operator experience must also be considered as LLR is technically demanding and requires experience in conventional hepatobiliary surgery and advanced laparoscopy. The main indication for LLR is limited resection of superficial or peripherally located tumors. In the case of malignant tumors, LLR should be indicated only if a safe and effective oncologic resection can be performed, and the availability of laparoscopy should not change the indications for benign lesions. Ultimately, the future application of LLR will depend on how easily liver surgeons can master the technique and whether the long-term results of LLR can match those achieved with open resection.

Early experiences of robotic-assisted laparoscopic liver resection

PURPOSE

The surgical robotic system is superior to traditional laparoscopy in regards to 3-dimensional images and better instrumentations. Robotic surgery for hepatic resection has not yet been extensively reported.

PATIENTS AND METHODS

Between March and May 2007, we performed 3 robot-assisted left lateral sectionectomies of the liver. Case 1 had a hepatocellular carcinoma (HCC), case 2 had colon cancer with liver metastasis, and case 3 had intrahepatic duct stones.

RESULTS

All patients had successful operation and recovered without complications. Shorter length of hospital stays, earlier start of oral feeding and less amount of ascites were found. However, case 1 had recurrent HCC at 3 months after operation.

CONCLUSION

Robotic-assisted liver surgery is still a new field in its developing stage. In patients with small malignant tumors and benign liver diseases, robotic-assisted laparoscopic resection is feasible and safe. Through experience, the use of robotics is expected to increase in the treatment of benign diseases and malignant neoplasms. However, careful patient selection is important and long-term outcomes need to be evaluated.

Effects of simulated carbon dioxide and helium peumoperitoneum on proliferation and apoptosis of gastric cancer cells

AIM

To investigate the effects of carbon dioxide (CO(2)) and helium insufflation administered at different pressures on the growth and apoptosis of cultured human gastric cancer cells.

METHODS

The gastric cancer cells MKN-45 were exposed to a CO(2) and helium environment maintained at different pressures (0, 5, 10 and 15 mmHg). The cells were exposed to simulated pneumoperitoneum environment for 4 h, and pH of the culture media was measured after it was moved to normal conditions for 0, 2, 4, 6 and 8 h. Proliferation viability of MKN-45 was examined by 3-[4,5Dimethylthiazol-2-yl],5-diphenyltetrazolium bromide or triazolyl blue (MTT) assay after it was moved to normal conditions. Apoptotic ratio was measured by Annexin V-FITC/PI double labelled staining.

RESULTS

The pH of media was acid and recovered to normal after 4 h in the CO(2) group while it was basic in the helium group. There was no difference between CO(2) groups (under 10 mmHg ) and control group (P > 0.05) in the proliferative viability of the cells. The cultured cells exposed to 15 mmHg CO(2) environment grew more slowly than control group from 4 to 7 d (P < 0.01 ) while there was no difference from 1 to 3 d (P > 0.05). The proliferative viability in helium group was not obviously different from the control group (P > 0.05). The apoptotic ratio of the cultured cells was markedly higher than that of the control group (P < 0.01) at 10 and 15 mmHg CO(2) insufflation pressure. In helium group, the apoptotic ratio was not obviously different from the control group (P > 0.05).

CONCLUSION

There is no obvious effect in the proliferation and apoptosis of MKN-45 cells under 10 mmHg CO(2) insufflation pressure and helium in any pressure. Fifteen mmHg CO(2) insufflation pressure can inhibit the proliferation of the cells and improve apoptosis.

Laparoscopic liver resection assisted with radiofrequency

BACKGROUND

Radiofrequency-assisted laparoscopic liver resection is reported.

METHODS

Patients suitable for liver resection were carefully assessed for laparoscopic resection. Patient and intraoperative and postoperative data were prospectively collected and analyzed.

RESULTS

Eighteen patients underwent laparoscopic liver resection. All operations were performed without vascular clamping and consisting of tumorectomy (n = 9), multiple tumoretcomies (n = 2), segmentectomy (n = 2), and bisegmentectomies (n = 2). Mean blood loss was 121 +/- 68 mL, and mean resection was time 167 +/- 45 minutes. There was no need for perioperative or postoperative transfusion of blood or blood products. One patient developed pneumothorax during surgery as a result of direct puncture of pleura with the radiofrequency probe, and 1 patient had transient liver failure and required supportive care after surgery. The mean length of hospital stay was 6.0 +/-1.5 days. At follow-up, those with liver cancer had no recurrence.

CONCLUSIONS

Radiofrequency-assist laparoscopic liver resection can decrease the risk of intraoperative bleeding and blood transfusion.

Laparoscopic versus open hepatic resections for benign and malignant neoplasms--a meta-analysis

BACKGROUND

Laparoscopic surgery for hepatic neoplasms aims to provide curative resection while minimizing complications. The present study compared laparoscopic versus open surgery for patients with hepatic neoplasms with regard to short-term outcomes.

METHODS

Comparative studies published between 1998 and 2005 were included. Evaluated endpoints were operative, functional, and adverse events. A random-effects model was used and sensitivity analysis performed to account for bias in patient selection.

RESULTS

Eight nonrandomized studies were included, reporting on 409 resections of hepatic neoplasms, of which 165 (40.3%) were laparoscopic and 244 (59.7%) were open. Operative blood loss (weighted mean difference = -123 mL; confidence interval = -179, -67 mL) and duration of hospital stay (weighted mean difference = -2.6 days; confidence interval = -3.8, -1.4 days) were significantly reduced after laparoscopic surgery. These findings remained consistent when considering studies matched for the presence of malignancy and segment resection. There was no difference in postoperative adverse events and extent of oncologic clearance.

CONCLUSIONS

Laparoscopic resection results in reduced operative blood loss and earlier recovery with oncologic clearance comparable with open surgery. When performed by experienced surgeons in selected patients it may be a safe and feasible option. Because of the potential of significant bias arising from the included studies, further randomized controlled trials should be undertaken to confirm this bias and to assess long-term survival rates.

Exposure to carbon dioxide and helium reduces in vitro proliferation of pediatric tumor cells

BACKGROUND

Minimally invasive techniques are increasingly applied to children with malignant tumors. We showed previously that CO(2) used for pneumoperitoneum modulates the function of macrophages and polymorphonuclear cells via direct effects and via acidification. Numerous in vitro and small animal model studies also confirmed an alteration of the behavior of several types of adult tumor cells by CO(2). The impact of CO(2) and other gases used for pneumoperitoneum on the behavior of various pediatric tumors has not yet been determined.

METHODS

Cell lines of neuroblastoma (IMR 32, SK-N-SH, Sy5y), lymphoma (Daudi), hepatoblastoma (Huh 6), hepatocellular carcinoma (Hep G2), and rhabdomyosarcoma (Te 671) were incubated for 2 h. Incubation was performed with 100% CO(2), 100% helium, and 5% CO(2) as control. Cell proliferation was determined by the MTT-assay [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] by actively growing cells to produce a blue formazan product. The MTT-assay was performed before, directly after incubation, and daily for 4 days. Vitality of the cells was determined by trypan blue. The extracellular pH during incubation was measured during gas exposition every 10 min using Bayer Rapid Lab 855.

RESULTS

CO(2) for 2 h significantly decreased the proliferation of neuroblastoma, lymphoma, hepatoblastoma, and hepatocellular carcinoma cells. This decrease persisted over 4 days in neuroblastoma, lymphoma, and hepatocellular carcinoma cells. The CO(2) had no impact on hepatoblastoma and rhabdomyosarcoma cells. Helium had a similar effect on neuroblastoma cells. After 4 days, a significant decrease of cell activity was found in two neuroblastoma cell lines and in hepatoblastoma cells. Helium had no effect on lymphoma and hepatocellular carcinoma cells. The extracellular pH was 6.2 during incubation with CO(2), and 7.6 during incubation with helium.

CONCLUSION

CO(2) and helium may affect the proliferation of some pediatric tumor cell lines in vitro. However, some of these effects and the impact on the extracellular pH are differential. The role of pH modulation, hypoxia and direct effects of gases remain to be investigated before a general recommendation on the use of minimally invasive techniques in pediatric oncology can be given.

Morphology of the murine peritoneum after pneumoperitoneum vs laparotomy

BACKGROUND

Although there have been studies of the effects of pneumoperitoneum on the peritoneal cavity, we still do not know whether the morphologic changes to the peritoneum are different for pneumoperitoneum vs laparotomy. Using scanning electron microscopy, we examined the murine peritoneum after pneumoperitoneum vs laparotomy and compared the changes.

METHODS

Forty-five mice were anesthetized with diethyl ether and divided into seven groups. Pneumoperitoneum was established at 5 mmHg for 30 min with carbon dioxide (CO(2)) (n = 9), helium (n = 9), and air (n = 9). One group underwent laparotomy for 30 min (n = 9), and a control group underwent anesthesia only (n = 3). CO(2) pneumoperitoneum was further established at 10 mmHg for 30 min (n = 3) and at 5 mmHg for 60 min (n = 3). After the procedures, the peritoneum was resected from the mesenterium of the small intestine in each animal and examined by scanning electron microscope for morphologic changes of the mesothelial cells.

RESULTS

Bulging up of the mesothelial cells was evident immediately after pneumoperitoneum, whereas detachment of the mesothelial cells was present immediately after laparotomy. Bulging up of the mesothelial cells was reduced at 24 h after CO(2) pneumoperitoneum and fully resolved at 72 h in all pneumoperitoneum groups, whereas the mesothelial cells remained detached at 72 h in the laparotomy group. Intercellular clefts were found immediately after helium pneumoperitoneum and were present at 24 h and 72 h after helium pneumoperitoneum, but they were not seen after air pneumoperitoneum and were only evident after CO(2) pneumoperitoneum at 10 mmHg. Depression of the mesothelial cell surface was observed when pneumoperitoneum lasted 60 min.

CONCLUSION

Morphologic peritoneal alterations after pneumoperitoneum differed from those after laparotomy and were influenced by the type of gas, amount of pressure, and duration of insufflation. These peritoneal changes after pneumoperitoneum may be associated with a specific intraperitoneal tumor spread after laparoscopic cancer surgery.

Liver tumors and minimally invasive surgery: a feasibility study

Laparoscopic liver resection has not yet been established, although recent reports document that liver resection can be performed safely by the laparoscopic approach. Other interventional procedures like cryoablation have also been introduced in treatment of liver metastases. In this report 11 liver resections performed laparoscopically in eight patients are presented. Six patients had colorectal metastases, one a metastases from a malignant melanoma, and one patient had focal nodular hyperplasia. Two patients received synchronous cryoablation of remaining liver metastases. During follow up, two patients received percutaneous cryoablation of liver recurrences monitored by an open configuration magnetic resonance scanner. All except one of the tumors we attempted to remove had free resection margins (re-resection of new metastasis). No complications occurred except an atelectasis of the left lower pulmonary lobe in one patient. Median postoperative hospital stay was 3 days, and median postoperative opioid-dependent days was 1. The report demonstrates that minimally invasive techniques may safely be combined in hepatic intervention, and that the advantages of minimally invasive surgery, such as reduced hospital stay and less patient discomfort, also applies to liver resections.

Risk of spread of ovarian cancer after laparoscopic surgery

The incidence of the spread of ovarian cancer after laparoscopic surgery is difficult to establish from the current literature. The prognosis incidence of a trocar site metastasis without peritoneal dissemination is not known. Data from general surgeons in prospective studies from a single institution suggested that in colon cancer the risk is low, whereas it seems to be much higher in multicentric studies of undiagnosed gallbladder cancer. Experimental studies suggested that laparoscopy has advantages and disadvantages. However, the risk of dissemination is high when a large number of malignant cells and a carbon dioxide pneumoperitoneum are present, a situation encountered when managing adnexal tumours with large vegetations. Animal studies will allow the development of a peritoneal environment adapted to the treatment of cancer. The ovary is an intraperitoneal organ and ovarian cancer a peritoneal disease, so the risk of peritoneal spread may be higher in ovarian cancer than in other gynecological cancers. A careful preoperative evaluation appears to be the best way to prevent these risks. It should also be used to choose which patient should be operated by which surgical team. The second step is a careful and cautious laparoscopic diagnosis, so that more than 98% of ovarian cancers encountered can be treated immediately and effectively. The laparoscopic management of ovarian cancer remains controversial; it should be performed only in prospective clinical trials. Until the results of such studies become available, an immediate vertical midline laparotomy remains the gold standard if a cancer is encountered.

Approaching the adnexal mass in the new millennium

Adnexal masses are common dilemmas faced by practicing gynecologists. They affect women from before birth throughout life, yet considerable disagreement exists regarding their optimal management. Traditional management focused on avoiding undertreatment of a potentially malignant process. Advances in detection, diagnosis, and minimally invasive management make it necessary to review this practice to avoid unnecessary morbidity and mortality. The literature emphasizes a minimally invasive approach to the treatment of benign lesions without sacrificing the principles of oncologic surgery.