Validation of a Nomogram to Predict Recurrence in Patients with Mucinous Neoplasms of the Appendix with Peritoneal Dissemination After Cytoreductive Surgery and HIPEC.

BACKGROUND: Survival of patients affected by mucinous appendiceal neoplasms with peritoneal dissemination (PD) is mainly related to histopathological features. However, prognostic stratification is still a concern, as the clinical course of the disease is often unpredictable. The aim of this study is to construct and externally validate a nomogram predicting disease-free survival (DFS) in mucinous appendiceal neoplasms with PD treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). PATIENTS AND METHODS: Patients treated in two referral centers were included: Hospital General Universitario Gregorio Marañón, Madrid, Spain (derivation cohort) and Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy (validation cohort). Cox regression analysis identified factors associated with shorter DFS in the derivation cohort. The nomogram performance was externally evaluated in the validation cohort using concordance index and calibration plots. Histology was classified according to the Peritoneal Surface Oncology Group International (PSOGI). RESULTS: The derivation cohort included 95 patients, and the validation cohort 348. Five-year DFS rates were 51.5 and 62%, respectively. Cox regression analysis (derivation cohort) identified PSOGI histology of the peritoneal components, number of preoperative elevated tumor marker, and peritoneal disease extent, as assessed by peritoneal carcinomatosis index, to be predictors of DFS. The model's predictive capacity was higher than that of PSOGI classification alone, with respective concordance indexes of 0.702 ± 0.023 and 0.610 ± 0.018 (validation cohort). The nomogram approximated the perfect model in the calibration plots at 3- and 5-year DFS. CONCLUSIONS: An easy-to-use model that provides better prognostic stratification than histopathological features has been constructed. This nomogram may help clinicians in individualized survival predictions and informed clinical decision-making.

Preliminary results of a program for the implementation of laparoscopic colorectal surgery in an Italian comprehensive cancer center during the COVID-19 pandemic.

Despite operative benefit and oncological non-inferiority, videolaparoscopic (VLS) colorectal surgery is still relatively underutilized. This study analyzes the results of a program for the implementation of VLS colorectal surgery started in an Italian comprehensive cancer center shortly before COVID-19 outbreak. A prospective database was reviewed. The study period was divided in four phases: Phase-1 (Open surgery), Phase-2 (Discretional phase), Phase-3 (VLS implementation phase), and Phase-4 (VLS consolidation phase). Formal surgical and perioperative protocols were adopted from Phase-3. Postoperative complications were scored by the Clavien-Dindo classification. 414 surgical procedures were performed during Phase-1, 348 during Phase-2, 360 during Phase-3, and 325 during Phase-4. In the four phases, VLS primary colorectal resections increased from 11/214 (5.1%), to 55/163 (33.7%), 85/151 (57.0%), and 109/147 (74.1%), respectively. The difference was statistically significant (P < 0.001). All-type VLS procedures were 16 (3.5%), 61 (16.2%), 103 (27.0%), and 126 (38.6%) (P < 0.001). Conversions to open surgery of attempted laparoscopic colorectal resections were 17/278 in the overall series (6.1%), and 12/207 during Phase-3 and Phase-4 (4.3%). Severe (grades IIIb-to-V) postoperative complications of VLS colorectal resections were 9.1% in Phase-1, 12.7% in Phase-2, 12.8% in Phase-3, and 5.3% in Phase-4 (P = 0.677), with no significant differences with open resections in each of the four phases: 9.4% (P = 0.976), 11.1% (P = 0.799), 13.8% (P = 1.000), and 8.3% (P = 0.729). Despite the difficulties deriving from the COVID-19 outbreak, our experience suggests that volume of laparoscopic colorectal surgery can be significantly and safely increased in a specialized surgical unit by means of strict operative protocols.

The Delphi and GRADE methodology used in the PSOGI 2018 consensus statement on Pseudomyxoma Peritonei and Peritoneal Mesothelioma.

Pseudomyxoma Peritonei (PMP) and Peritoneal Mesothelioma (PM) are both rare peritoneal malignancies. Currently, affected patients may be treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy offering long-term survival or even cure in selected patients. However, many issues regarding the optimal treatment strategy are currently under debate. To aid physicians involved in the treatment of these patients in clinical decision making, the PSOGI executive committee proposed to create a consensus statement on PMP and PM. This manuscript describes the methodology of the consensus process. The Delphi technique is a reliable method for attaining consensus on a topic that lacks scientific evidence through multiple voting rounds which feeds back responses to the participants in between rounds. The GRADE system provides a structured framework for presenting and grading the available evidence. Separate questionnaires were created for PMP and PM and sent during two voting rounds to 80 and 38 experts, respectively. A consensus threshold of 51.0% was chosen. After the second round, consensus was reached on 92.9%-100.0% of the questions. The results were presented and discussed in the plenary session at the PSOGI 2018 international meeting in Paris. A third round for the remaining issues is currently in progress. In conclusion, using the Delphi technique and GRADE methodology, consensus was reached in many issues regarding the treatment of PM and PMP amongst an international panel of experts. The main results will be published in the near future.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment.

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

The Delphi and GRADE methodology used in the PSOGI 2018 consensus statement on Pseudomyxoma Peritonei and Peritoneal Mesothelioma

Pseudomyxoma Peritonei (PMP) and Peritoneal Mesothelioma (PM) are both rare peritoneal malignancies. Currently, affected patients may be treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy offering long-term survival or even cure in selected patients. However, many issues regarding the optimal treatment strategy are currently under debate. To aid physicians involved in the treatment of these patients in clinical decision making, the PSOGI executive committee proposed to create a consensus statement on PMP and PM. This manuscript describes the methodology of the consensus process. The Delphi technique is a reliable method for attaining consensus on a topic that lacks scientific evidence through multiple voting rounds which feeds back responses to the participants in between rounds. The GRADE system provides a structured framework for presenting and grading the available evidence. Separate questionnaires were created for PMP and PM and sent during two voting rounds to 80 and 38 experts, respectively. A consensus threshold of 51.0% was chosen. After the second round, consensus was reached on 92.9%-100.0% of the questions. The results were presented and discussed in the plenary session at the PSOGI 2018 international meeting in Paris. A third round for the remaining issues is currently in progress. In conclusion, using the Delphi technique and GRADE methodology, consensus was reached in many issues regarding the treatment of PM and PMP amongst an international panel of experts. The main results will be published in the near future.

Toward the molecular dissection of peritoneal pseudomyxoma.

BACKGROUND: Outcome of pseudomyxoma peritonei (PMP) after cytoreductive surgery (CRS) and hypertermic intraperitoneal chemotherapy (HIPEC) is heterogeneous even after adjusting for clinico-pathological prognostic variables. The identification of additional prognostic or even predictive biomarkers is an unmet clinical need. PATIENTS AND METHODS: Forty patients with mucinous appendiceal tumors and PMP were clinically eligible and had evaluable tumor samples obtained after CRS and HIPEC. We carried out next-generations sequencing (NGS) of 50 gene's hotspot regions contained in the Hotspot Cancer Panel v2 using the Ion Torrent Personal Genome Machine platform (Life Technologies). RESULTS: KRAS and GNAS mutations were found in 72% and 52%, and their allelic frequency was below 10% in 55% and 43% of samples, respectively. KRAS and GNAS mutations were associated with worse progression-free survival (PFS) at univariate analysis (P = 0.006 and 0.011, respectively). At multivariate analysis, only KRAS mutations were independently associated with PFS (P = 0.012); GNAS mutations were not-being significantly associated with other poor prognostic features such as incomplete cytoreduction or KRAS mutations. Validation of results was carried out in an independent bi-institutional cohort of 25 patients and the prognostic effect of KRAS mutations was again confirmed in the multivariate model (P = 0.029). NGS approach allowed the discovery of other potentially druggable mutations such as those in PI3K, AKT, LKB1, FGFR3 and PDGFRA. CONCLUSIONS: Given the homogeneity of this series and the sensitivity of NGS in this low-cellularity tumor, we demonstrated for the first time a poor prognostic role of KRAS mutations.

The role of baseline inflammatory-based scores and serum tumor markers to risk stratify pseudomyxoma peritonei patients treated with cytoreduction (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

AIMS: Inflammation-based scores such as neutrophil-lymphocyte ratio (NLR) and Onodera nutritional index (ONI) have been identified as new prognosticators in several tumors. We conducted a prognostic analysis of these markers and performed a risk stratification of PMP patients submitted to cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: 226 patients from two peritoneal surface malignancies centers participated in this study. Cox proportional modeling was used to select predictors of overall survival (OS) among baseline inflammation-based scores, serum tumor markers, clinical and surgical variables. Risk stratification was done using conditional inference tree model. RESULTS: One hundred eighty-two cases had diffuse peritoneal adenomucinosis subtype. Fifty-four cases had received previous systemic chemotherapy. The means of ONI and NLR were 51.4 (SD = 9.8) and 3.2 (SD = 2.3), respectively. Two hundred ten cases were optimally cytoreduced. Cox analysis identified completeness of cytoreduction, histological subtype, previous systemic chemotherapy, NLR, and CA 19-9 as independent prognosticators. Conditional inference tree method identified two poor prognostic subsets: NLR ≤2.7 and CA 19-9>336 (5yr-OS = 15%) and NLR >2.7 and ONI ≤42 (5yr-OS = 30%). CONCLUSIONS: NLR, ONI, and CA 19-9 are new prognosticators that contributed to improve prediction of OS in PMP patients treated by CRS and HIPEC. These markers allowed a risk stratification that could optimize therapeutic management of PMP patients.

Peritoneal metastases: challenges for the surgeon.

Peritoneal surface malignancies (PSM) include peritoneal metastases from gastrointestinal and gynecological tumor and rare primary peritoneal malignancies. PSM have been historically considered as end-stage metastatic conditions only amenable to palliative options. Only in recent years, better knowledge of their natural history and pattern of disease-progression has evolved into the concept that PSM represent a local-regional disease stage. A novel treatment approach aiming at definitive disease eradication combines aggressive cytoreductive surgery (CRS) and perioperative local-regional chemotherapy, either in the form of hyperthermic intraperitoneal chemotherapy (HIPEC), or normothermic early postoperative chemotherapy. Such a combined treatment approach has reportedly resulted in a survival improvement over historical controls, and it is gaining an increasing acceptance as standard of care for selected patients with PSM. This article reviews the most recent literature data on the surgical and comprehensive management of PSM. Epidemiology and natural history of the different disease entities are briefly discussed. Cytoreductive surgical procedures and intraperitoneal chemotherapy administration techniques are described, focusing on the technical variants adopted in our institution. Indications for combined treatment, and outcomes following CRS/HIPEC, are addressed, including peritoneal metastases from appendiceal tumors (pseudomyxoma peritonei), colorectal cancer, gastric cancer, epithelial ovarian cancer, and rare primary peritoneum based neoplasms, such as diffuse malignant peritoneal mesothelioma, and primary peritoneal (extra-ovarian) serous papillary carcinoma.

Multicentre study of the learning curve and surgical performance of cytoreductive surgery with intraperitoneal chemotherapy for pseudomyxoma peritonei.

BACKGROUND: The learning curves for cytoreductive surgery with intraperitoneal chemotherapy for treatment of pseudomyxoma peritonei (PMP) were explored between international centres/surgeons to identify institutional or other factors that might affect performance. METHODS: Data from patients with PMP treated with the combined procedure across 33 international centres between 1993 and 2012 were analysed retrospectively. A risk-adjusted sequential probability ratio test was conducted after defining the target outcome as early oncological failure (disease progression within 2 years of treatment), an acceptable risk for the target outcome (odds ratio) of 2, and type I/II error rates of 5 per cent. The risk prediction model was elaborated and patients were evaluated sequentially for each centre/surgeon. The learning curve was considered to be overcome and proficiency achieved when the odds ratio for early oncological failure became smaller than 2. RESULTS: Rates of optimal cytoreduction, severe postoperative morbidity and early oncological failure were 84·4, 25·7 and 29·0 per cent respectively. The median annual centre volume was 17 (range 6-66) peritoneal malignancies. Only eight of the 33 centres and six of 47 surgeons achieved proficiency after a median of 100 (range 78-284) and 96 (86-284) procedures respectively. The most important institutional factor affecting surgical performance was centre volume. CONCLUSION: The learning curve is extremely long, so centralization and/or networking of centres is necessary to assure quality of services. One centre for every 10-15 million inhabitants would be ideal.

Postoperative complications after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy affect long-term outcome of patients with peritoneal metastases from colorectal cancer: a two-center study of 101 patients.

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy is an effective but potentially morbid treatment for colorectal cancer peritoneal metastases. The impact of treatment-related morbidity on long-term survival has been reported in various malignancies, but it has never been assessed in this clinical setting. OBJECTIVE: The aim of this study was to assess the impact of major postoperative complications on oncological outcomes after cytoreduction and hyperthermic intraperitoneal chemotherapy for colorectal peritoneal metastases. DESIGN: Two prospective databases were reviewed. Major complications were defined as grade 3 to 5 according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. The extent of peritoneal involvement was scored by the use of the Peritoneal Cancer Index. SETTINGS: This study was conducted in 2 high-volume peritoneal malignancy management centers. PATIENTS: One hundred one consecutive patients with peritoneal metastases potentially amenable to macroscopically complete cytoreduction were selected. INTERVENTIONS: Peritonectomy procedures and multivisceral resections were used to remove all macroscopic tumor, and mitomycin-C plus cisplatin-based hyperthermic intraperitoneal chemotherapy was used to control microscopic residual disease. MAIN OUTCOME MEASURES: The primary outcomes measured were overall and disease-specific survival. RESULTS: Mortality and major morbidity were 3.0%, and 23.8%. Median follow-up was 44.9 months (95% CI, 24.1-65.7). Five-year disease-specific survival was 14.3% for patients who experienced major complications and 52.3% for those who did not (p = 0.001). Five-year overall survival was 11.7% for patients who experienced major complications, and 58.8% for those who did not (p = 0.003). At multivariate analysis, major morbidity correlated to both worse overall and disease-specific survival, along with a Peritoneal Cancer Index >19, and suboptimal cytoreduction. Poor performance status correlated only to worse disease-specific survival, and liver metastases correlated to worse overall survival. Longer operative time (OR, 4.1; 95% CI, 1.3-12.6; p = 0.01) and Peritoneal Cancer Index >19 (OR, 2.6; 95% CI, 1.1-6.0; p = 0.02) were independent risk factors for major morbidity. LIMITATIONS: This study is limited by its observational design. CONCLUSIONS: The prevention of major complications, by refining surgical technique and patient selection, is crucial because it affects oncologic outcome.

Secondary cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for recurrent epithelial ovarian cancer: a multi-institutional study.

OBJECTIVE: To assess the efficacy and morbidity and mortality of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in recurrent epithelial ovarian cancer (EOC). DESIGN: A retrospective study conducted using information extracted from a multi-institutional prospective database on peritoneal surface malignancies (PSMs). Setting Four Italian centres specializing in locoregional treatment of PSM. POPULATION: Patients with recurrent EOC. METHODS: Fifty-six patients underwent 57 combined procedures. CRS was performed using peritonectomy procedures and HIPEC using the closed-abdomen technique with cisplatin and doxorubicin or cisplatin and mitomycin-C. MAIN OUTCOME MEASURES: Overall survival (OS), progression-free survival (PFS), morbidity and mortality rates. RESULTS: The median age of the patients was 55.2 years (range 30-75 years). The median peritoneal cancer index was 15.2 (range 4-30). Forty-seven patients had microscopic residual disease (completeness of cytoreduction, CC-0), seven had residual disease ≤2.5 mm (CC-1) and one had residual disease >2.5 mm (CC>2). Major complications occurred in 15 patients (26.3%), and procedure-related mortality occurred in three patients (5.3%). The median follow-up time was 23.1 months. The median OS and PFS were 25.7 (95% CI 20.3-31.0) and 10.8 (95% CI 5.4-16.2) months, respectively. The 5-year OS and PFS were 23% and 7%, respectively. Independent prognostic factors affecting OS according to the multivariate analysis were Eastern Cooperative Oncology Group performance status, preoperative serum albumin, and completeness of cytoreduction. CONCLUSIONS: Patients with recurrent EOC treated with CRS and HIPEC showed promising results in terms of outcome. The combined treatment strategy could benefit subsets of patients wider than that defined for conventional secondary debulking surgery without HIPEC. These data warrant further evaluation in randomised clinical trials.

Advanced cytoreduction as surgical standard of care and hyperthermic intraperitoneal chemotherapy as promising treatment in epithelial ovarian cancer.

Favorable oncological outcomes have been reported in several trials with the introduction of Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in the treatment of Advanced Epithelial Ovarian Cancer (EOC). However most of the studies testing the combined approach are observational and have been conducted in inhomogeneous series so that the evidence supporting the performance of this combined treatment is still poor. Median Overall and Disease Free Survivals of up to 64 months and 57 months, respectively have been reported. Although a rate of morbidity of up to 40% has been observed in some series the CRS + HIPEC continues to gain an increased popularity. Several prospective randomized trials are ongoing using the procedure in various time points of the disease. In this review several issues such as the impact of cytoreduction and residual disease (RD) on outcomes as well as the role of HIPEC will be updated from the literature evidence. Some controversial points HIPEC related will also be discussed. Recent experiences regarding the introduction of a more aggressive surgical approach to upper abdomen to resect peritoneal carcinomatosis (PC) allowed increased rates of optimal cytoreduction and has demonstrated an apparent better outcome. This evidence associated with the positive results phase III trial testing normothermic intraperitoneal as first-line chemotherapy is guiding some investigators to propose the CRS + HIPEC in the primary setting. Several prospective phase II and III trials have recently been launched to validate the role of the combined treatment in various time points of disease natural evolution.

Multicystic peritoneal mesothelioma: outcomes and patho-biological features in a multi-institutional series treated by cytoreductive surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC).

AIM: This retrospective multi-institutional study addresses the role of surgical cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) in the treatment of multicystic peritoneal mesothelioma (MCPM). MCPM is an uncommon tumour with uncertain malignant potential and no current standard therapy. Additionally, poorly defined pathological and biological features of this disease were investigated. METHODS: Twelve patients with MCPM underwent 14 procedures of cytoreduction and HIPEC in two Italian referral centres. Nine patients had recurrent disease after previous debulking (one operation in six patients, two in two, four in one). Biological markers related to mesothelioma origin and clinical features were assessed by immunohistochemical studies. RESULTS: Median follow-up was 64 months (range 5-148). Optimal cytoreduction (residual tumour nodules ≤2.5 mm) was performed in all the procedures. One grade IV postoperative complication (NCI/CTCAE v.3.0) and no operative death occurred. All the patients are presently alive with no evidence of disease, including two patients who underwent the procedure twice, due to locoregional disease recurrence. Five- and ten-year progression-free survival was 90% and 72%, accounting for a. statistically significant difference (P = 0.0001) with progression-free survival following previous debulking surgery (median 11 months; range 2-31). All cases showed low proliferative activity assessed by mitotic rate and Ki-67 expression. CONCLUSIONS: MCPM is a borderline tumour with a high propensity to local-regional recurrence. Definitive tumour eradication by means of cytoreduction and HIPEC seems more effective than debulking surgery in preventing disease relapse. Low mitotic rate and poor Ki-67 expression might be related to the peculiar behaviour of MCMP.

Cost analysis of the combined procedure of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC).

AIM: The aim of the present study was to address the economic cost of the innovative comprehensive approach involving cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) to treat peritoneal surface malignancies, and to compare it with the financial support received by our centre. METHODS: A retrospective economic analysis was carried out on 382 consecutive procedures performed at a tertiary referral centre during the period 1995-2008. The costs of the combined therapy were estimated using the activity-based costing methodology. The financial support was assessed according to the current diagnosis-related group classification and reimbursement rates. RESULTS: The mean cost for one hospital stay was euro36,015.89 (range 28,435.24-82,189.08); mean length of stay was 24.3 days (range 9-108). In counterpart, our hospital received a total financial support of euro804,483.30, resulting in a deficit of euro1861,301.99 for the two years. CONCLUSION: The Italian current diagnosis-related groups classification does not include cytoreduction and HIPEC. This results in a relevant economic deficit for the hospitals offering this treatment option to their patients and a slow diffusion of the technique in our country. Two corrective measures are needed: to include this procedure in the official list of medical acts, and to determine its specific cost for reimbursing.

Diffuse malignant peritoneal mesothelioma: Failure analysis following cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC).

Improved survival has been reported for diffuse malignant peritoneal mesothelioma (DMPM) treated by cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC). The issue of treatment failure has never been extensively addressed. The present study assessed the failure pattern, management, and outcome of progressive DMPM following comprehensive treatment. Clinical data on 70 patients with DMPM undergoing cytoreduction and HIPEC were prospectively collected; after a median follow-up of 43 months, disease progression occurred in 38 patients. Progressive disease distribution in 13 abdominopelvic regions was analyzed. In 28 patients undergoing adequate cytoreduction (residual tumor < or =2.5 mm), clinicopathological factors correlating to disease progression in each region were investigated. Median time to progression was 9 months [95% confidence interval (CI) 1.6-35.9]. Median survival from progression was 8 months (95% CI 4-16.2). The failure pattern was categorized as peritoneal progression (n = 31), liver metastases (n = 1), abdominal lymph-node involvement (n = 2), pleural seeding (n = 4). Small bowel was the single site most commonly involved (n = 27). Residual tumor < or =2.5 mm (versus no visible) was the only independent risk factor for disease progression in epigastric region (P = 0.047), upper ileum (P = 0.029), upper jejunum (P = 0.034), and lower jejunum (P = 0.002). Progressive disease was treated with second HIPEC in 3 patients, debulking in 4, systemic chemotherapy in 16, and supportive care in 15. At multivariate analysis, time to progression <9 months (P = 0.009), poor performance status (P = 0.005), and supportive care (P = 0.003) correlated to reduced survival from progression. We conclude that minimal residual disease, compared with macroscopically complete cytoreduction, correlated to failure in critical anatomical areas, suggesting the need for maximal cytoreductive surgical efforts. In selected patients, aggressive management of progressive disease seems worthwhile.