Epithelial ovarian cancer (EOC) is the leading cause of death in gynaecologic malignancies. Ovarian cancer is usually diagnosed in an advanced stage, when tumour has spread from the ovaries throughout the abdominal cavity or into the liver parenchyma and pleural cavity (FIGO stage III or IV respectively). In advanced stage disease many patients have multiple tumour deposits spread out over the peritoneum, peritoneal carcinosis. Although survival of early stages is high, the survival of advanced stages is low. Despite an initial response rate of 80% after first line treatment, recurrences occur in 70% of patients, and the expected overall survival is 2 to 4 years.
Standard treatment of patients with advanced disease is primary cytoreductive (debulking) surgery (PDS), intended to remove all visible tumor localizations . Surgery is followed by six courses of chemotherapy consisting of Paclitaxel and Carboplatin. Result of debulking surgery is the most important prognostic factor for survival [1–4] Leaving no residual tumour gives the best survival. However, if complete resection is not possible, the goal of surgery is to achieve at least residual disease smaller than one centimetre in diameter. The present rate of patients with residual tumour smaller than one centimetre in Europe is only 20-62% [5, 6]. In case a tumour deposit of more than one centimetre is left at PDS some patients will be operated again after three courses of chemotherapy, a so called interval debulking surgery (IDS). Only those patients for who PDS was not considered to a maximal attempt by a gynaecological oncologist are candidate for this intervention . A PDS leaving more than one centimetre of tumour is an unsuccessful laparotomy leading to more morbidity without gain in survival. It lengthens hospital stay and time of treatment and increases costs and should therefore be avoided.
Computed tomography (CT) is now used in pre-operative staging of patients with an ovarian tumour for predicting operability and to determine treatment [8–10]. CT criteria have been developed which are used to select patients for primary surgery . Bristow et al. developed a model based on 13 criteria, like peritoneal thickening or bowel mesentery involvement, achieving an overall accuracy of 93% in predicting successful cytoreduction . However, this result could not be achieved using the same criteria in another patient population . Recently, Ferrandina developed a predictive score based on CT criteria as well as performance status . Depending on the model and the predictive score used, 33% to 48% of patients would have had a suboptimal debulking, despite the prediction that complete removal would be feasible. Although CT is at present the most predictive procedure, it is not accurate enough to guide clinical management. [12, 13]
Recently a randomized study of the European Organization of Research and Treatment of Cancer-Gynaecological Cancer Group (EORTC-GCG) and the NCIC-Clinical Trials Group comparing PDS and chemotherapy with neoadjuvant chemotherapy (NACT) followed by IDS was conducted . Although survival was comparable in both groups, a subgroup analysis showed that patients with metastases with a diameter of less than five cm at start of primary debulking have a better prognosis when treated by PDS. Emphasizing the fact that PDS should be the standard treatment and that neoadjuvant chemotherapy should be reserved to patients in whom optimal debulking is deemed not feasible or who can not tolerate the procedure [6, 14]. Therefore, selection of patients is very important and could be done by using laparoscopy to predict operability results [6, 15].
Several prospective and retrospective studies have investigated the use of laparoscopy to predict outcome of debulking surgery. In a pilot study by Fagotti et al.  laparoscopy predicted debulking leaving tumour residual more than one centimetre in 100% of cases and debulking surgery with no macroscopic tumour left in 89% of cases . With these data Fagotti et al. developed a prediction model with accuracy for prediction of unsuccessful debulking between 69% and 75% depending on the cutoff level of the Predictive Index Value used . However, validation of this prediction model in another study population by Brun et al. showed that 56% of patients who were thought to have debulking until less than 1 cm of tumour residual underwent a unsuccessful resection .
Despite the absence of strong evidence and despite possible complications laparoscopy is already implemented in many countries. In this respect, we propose a randomized controlled clinical trial in which the outcome of PDS after diagnostic laparoscopy is compared with the outcome of PDS after standard diagnostic work-up.