Is Systemic Chemotherapy Useful in Patients Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for Colorectal Peritoneal Metastases? A Propensity-Score Analysis.

PURPOSE: Multimodal treatment of colorectal (CRC) peritoneal metastases (PM) includes systemic chemotherapy (SC) and surgical cytoreduction (CRS), eventually with hyperthermic intraperitoneal chemotherapy (HIPEC), in select patients. Considering lack of clear guidelines, this study was designed to analyze the role of chemotherapy and its timing in patients treated with CRS-HIPEC. METHODS: Data from 13 Italian centers with PM expertise were collected by a collaborative group of the Italian Society of Surgical Oncology (SICO). Clinicopathological variables, SC use, and timing of administration were correlated with overall survival (OS), disease-free survival (DFS), and local (peritoneal) DFS (LDFS) after propensity-score (PS) weighting to reduce confounding factors. RESULTS: A total of 367 patients treated with CRS-HIPEC were included in the propensity-score weighting. Of the total patients, 19.9% did not receive chemotherapy within 6 months of surgery, 32.4% received chemotherapy before surgery (pregroup), 28.9% after (post), and 18.8% received both pre- and post-CRS-HIPEC treatment (peri). SC was preferentially administered to younger (p = 0.02) and node-positive (p = 0.010) patients. Preoperative SC is associated with increased rate of major complications (26.9 vs. 11.3%, p = 0.0009). After PS weighting, there were no differences in OS, DFS, or LDFS (p = 0.56, 0.50, and 0.17) between chemotherapy-treated and untreated patients. Considering SC timing, the post CRS-HIPEC group had a longer DFS and LDFS than the pre-group (median DFS 15.4 vs. 9.8 m, p = 0.003; median LDFS 26.3 vs. 15.8 m, p = 0.026). CONCLUSIONS: In patients with CRC-PM treated with CRS-HIPEC, systemic chemotherapy was not associated with overall survival benefit. The adjuvant schedule was related to prolonged disease-free intervals. Additional, randomized studies are required to clarify the role and timing of systemic chemotherapy in this patient subset.

Microsatellite and RAS/RAF Mutational Status as Prognostic Factors in Colorectal Peritoneal Metastases Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC).

BACKGROUND: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) leads to prolonged survival for selected patients with colorectal (CRC) peritoneal metastases (PM). This study aimed to analyze the prognostic role of micro-satellite (MS) status and RAS/RAF mutations for patients treated with CRS. METHODS: Data were collected from 13 Italian centers with PM expertise within a collaborative group of the Italian Society of Surgical Oncology. Clinical and pathologic variables and KRAS/NRAS/BRAF mutational and MS status were correlated with overall survival (OS) and disease-free survival (DFS). RESULTS: The study enrolled 437 patients treated with CRS-HIPEC. The median OS was 42.3 months [95% confidence interval (CI), 33.4-51.2 months], and the median DFS was 13.6 months (95% CI, 12.3-14.9 months). The local (peritoneal) DFS was 20.5 months (95% CI, 16.4-24.6 months). In addition to the known clinical factors, KRAS mutations (p = 0.005), BRAF mutations (p = 0.01), and MS status (p = 0.04) were related to survival. The KRAS- and BRAF-mutated patients had a shorter survival than the wild-type (WT) patients (5-year OS, 29.4% and 26.8% vs 51.5%, respectively). The patients with micro-satellite instability (MSI) had a longer survival than the patients with micro-satellite stability (MSS) (5-year OS, 58.3% vs 36.7%). The MSI/WT patients had the best prognosis. The MSS/WT and MSI/mutated patients had similar survivals, whereas the MSS/mutated patients showed the worst prognosis (5-year OS, 70.6%, 48.1%, 23.4%; p = 0.0001). In the multivariable analysis, OS was related to the Peritoneal Cancer Index [hazard ratio (HR), 1.05 per point], completeness of cytoreduction (CC) score (HR, 2.8), N status (HR, 1.6), signet-ring (HR, 2.4), MSI/WT (HR, 0.5), and MSS/WT-MSI/mutation (HR, 0.4). Similar results were obtained for DFS. CONCLUSION: For patients affected by CRC-PM who are eligible for CRS, clinical and pathologic criteria need to be integrated with molecular features (KRAS/BRAF mutation). Micro-satellite status should be strongly considered because MSI confers a survival advantage over MSS, even for mutated patients.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Gastric Cancer with Synchronous Peritoneal Metastases: Multicenter Study of 'Italian Peritoneal Surface Malignancies Oncoteam-S.I.C.O.'

BACKGROUND: The development of multimodality treatment, including cytoreductive surgery (CRS) with heated intraperitoneal chemotherapy (HIPEC), has led to promising results in selected patients with peritoneal disease of gastric origin. The aim of this study was to investigate the short- and long-term outcomes of CRS/HIPEC in the treatment of synchronous peritoneal metastasis in gastric cancer. METHODS: The Italian Peritoneal Surface Malignancies Oncoteam-S.I.C.O. retrospective registry included patients with synchronous peritoneal malignancy from gastric cancer submitted to gastrectomy with CRS and HIPEC between 2005 and 2018 from 11 high-volume, specialized centers. RESULTS: A total of 91 patients with a median age of 58 years (range 26-75) were enrolled. The median overall survival (OS) time for the whole group of patients was 20.2 months (95% confidence interval [CI] 11.8-28.5] and the median recurrence-free survival (RFS) was 7.3 months (95% CI 4-10.6). The completeness of cytoreduction score (CCS) of 0 and Peritoneal Cancer Index (PCI) score of ≤ 6 groups showed a significantly better long-term survival (median OS 40.7 and 44.3 months, respectively) compared with the incomplete resected groups (median OS 10.7 months, p = 0.003) and PCI score of > 6 group (median OS 13.4 months, p = 0.005). A significant difference was observed in the survival rate according to neoadjuvant treatment (untreated patients: 10.7 months, 95% CI 5.1-16.2; treated patients: 35.3 months, 95% CI 2.8-67.8; p = 0.022). CONCLUSIONS: In referral centers, CRS and HIPEC after neoadjuvant treatment significantly improved survival in selected patients. Patients with a PCI score ≤ 6, complete cytoreduction, negative nodal involvements, and negative cytology had encouraging results, showing a clinically meaningful survival.

Short-term outcome of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy used as treatment of colo-rectal carcinomatosis: a multicentric study.

The aim of this study is to assess the morbidity and mortality related to cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with colo-rectal carcinomatosis. A retrospective multi-institutional study from seven Italian Centers was performed. One hundred and seventy-two patients, submitted to cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) to treat carcinomatosis of colorectal origin, were recorded. Postoperative morbidity was evaluated in accordance with the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Post-operative mortality was evaluated as patients' death within 60 days from surgical procedures. Predictors of morbidity were evaluated with univariate and multivariate analyses. Post-operative morbidity occurred in 83 patients (48.3%): grades 1-2 in 29 cases (16.9%), and grades 3-4 in 54 (31.4%). Mortality occurred in four cases (2.3%). Number of anastomoses (OR 1.45; 95% CI 1.05-2.00; p = 0.024), number of blood transfusions (OR 1.31; 95% CI 1.11-1.54; p = 0.001) and chemotherapy regimen [Oxaliplatin (OX): OR 2.87; 95% CI 1.22-6.75; p = 0.015] remained, in multivariate analysis, in a statistically significant correlation with overall morbidity. The only variable that was proven to have statistically significant correlation with 3-4 morbidity was the number of blood transfusions (OR 1.25; 95% CI 1.07-1.46; p = 0.005). Morbidity and mortality do not preclude the use of CRS plus HIPEC in the treatment of peritoneal carcinomatosis of colorectal origin.

Upfront debulking surgery versus interval debulking surgery for advanced tubo-ovarian high-grade serous carcinoma and diffuse peritoneal metastases treated with peritonectomy procedures plus HIPEC.

BACKGROUND: Whether patients with advanced tubo-ovarian high-grade serous cancer (HGSC) fare better after upfront debulking surgery (UDS) or neoadjuvant chemotherapy with interval debulking surgery (NACT-IDS) remains controversial. METHODS: We studied patients with HGSC who underwent UDS or NACT-IDS between July 2000 and December 2015, with peritonectomy procedures combined with hyperthermic intraperitoneal chemotherapy (HIPEC). Clinical reports were included peritoneal cancer index (PCI), NACT responses, surgical complexity score (SCS), completeness of cytoreduction (CC), complete follow-up with timing, site, and treatment of recurrence. Outcome measures were morbidity, progression-free survival (PFS), PFS2, and overall survival during a mean 5-year follow-up. RESULTS: A total of 34 patients (23.6%) underwent UDS and 110 (76.4%) NACT-IDS both combined with HIPEC. At a median 66.3-month follow-up, patients who underwent UDS or NACT-IDS had similar outcomes. NACT subgroup responses correlated with PCI, SCS, morbidity, and CC. Patients who underwent UDS had lower recurrence rates than those who responded partly or poorly to NACT (PFS, P < .04; PFS2, P < .01). Despite HIPEC, the peritoneal disease recurred in 42.5% of the overall patients. CONCLUSION: In patients with primary HGSC who undergo UDS or NACT-IDS, despite similar outcomes, peritonectomy procedures combined with HIPEC seem unable to prevent peritoneal recurrence.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: morbidity and postoperative outcomes.

BACKGROUND: Cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) represents a treatment option for peritoneal surface malignancies. Even if it has been reported that this new approach improved survival of selected patients, it is still associated with high morbidity and mortality rates. METHODS: From October 1995 to December 2017, over 450 patients affected by peritoneal carcinomatosis (PC) underwent in our Institute CRS associated with HIPEC. For this preliminary analysis we considered 300 patients presenting PC of different origin: pseudomyxoma peritonei (PMP, N.=98), epithelial ovarian cancer (EOC, N.=87), peritoneal mesothelioma (DMPM, N.=49) and colorectal cancer (CRC, N.=66). Postoperative morbidity and mortality were studied in order to identify possible risk factors. RESULTS: The morbidity rate was 36.3% in all procedures (109/300). According to the Clavien-Dindo Classification, 67 cases (22.3%) were associated with grade I-II complications and 35 cases (11.7%) with grade III-IV. Surgical and medical complication rates were 8.3% (25/300) and 11.3% (34/300), respectively. The mortality rate was 2.3%. Reoperation was needed in 28 patients (9.3%). The operative time, the number of anastomosis, of peritonectomy procedures, of visceral resections performed and the PCI value resulted the most statistically significant factors influencing postoperative morbidity and mortality. CONCLUSIONS: The risks of perioperative morbidity and mortality after CRS and HIPEC are analogous to any other major gastrointestinal surgery. CRS and HIPEC should remain a treatment option for highly-selected patients in whom a curative or life prolonging treatment is a pursuit and should be performed in high volume specialized institutions.

Analysis of patient selection policy and pattern of recurrence after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for colorectal carcinomatosis.

BACKGROUND: Actual cure rate and patterns of recurrence after cytoreductive surgery (CRS) associated to hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with colorectal peritoneal carcinomatosis (PC) are not yet well explored. Moreover, the selection policy to this resource-consuming treatment is still a matter of debate. METHODS: From a dataset of 400 CRS+HIPEC performed between October 1996 and December 2015, we selected 54 consecutive patients with colorectal PC. Exclusion criteria were age>70, PS>2, or disease progression during chemotherapy. From 2004, we also excluded patients with both PCI>16 and poor prognostic factors of primary tumor (i.e. T4, N2 and G3) and only proceeded to HIPEC in case of optimal cytoreduction. Prognostic factors, cure rate and patterns of recurrence were investigated, comparing the two time periods. RESULTS: After 2004, median overall survival was 52 months, with a 40% 5-year survival. Completeness of cytoreduction, primary tumor histology and time period were independent prognostic factors. Median recurrence-free survival was 16 months. A relapse was detected in 41 out of 46 patients with optimal cytoreduction. Main sites of first relapse were peritoneum (73%), and distant metastases (37%), mainly to liver and lungs. Peritoneal and liver/lung metastases presented as isolated recurrence in 73% and 58% of cases, respectively. CONCLUSIONS: By a selection policy based on patient, disease extension and primary tumor factors, a median survival higher than 50 months can be expected. Most patients will eventually recur, mainly in the peritoneum. The pattern of recurrence suggests a potential role for more effective intraperitoneal therapies and repeat surgical treatments.

Low-dose Pressurized Intrathoracic Aerosol Chemotherapy (PITAC) as an Alternative Therapy for Pleuropulmonary Involvement in Pseudomyxoma Peritonei.

BACKGROUND/AIM: Pseudomyxoma peritonei (PMP) is a rare disease characterized by mucinous ascites and widespread peritoneal implants. It usually originates from the rupture of an adenoma/adenocarcinoma of the appendix. Although this tumor is only superficially invasive and does not metastasize, it could be a fatal disease. Extra-abdominal spread of PMP is an unusual occurrence with few reports in medical literature. CASE REPORT: A 50-year-old man was diagnosed with PMP according to the findings of thorax and abdomen CT scan and cytologic and histological examinations. The radiological exam showed irregular thickening on the surface of left diaphragmatic and parietal pleura. RESULTS: First, cytoreductive surgery associated with hyperthermic intraperitoneal chemotherapy (HIPEC) for the abdominal disease was performed. Histopathological examination confirmed the diagnosis of low grade PMP. The radiological evaluation performed 5 months later showed a dimensional increase in pleural nodules. The treatment consisted of an extensive intrathoracic cytoreductive surgery in combination with pressurized intra-thoracic aerosol chemotherapy (PITAC). Postoperative course was uneventful. CONCLUSION: PMP with pleural extension is a rare phenomenon and carries an unfavourable prognosis. Due to the rarity of this presentation, its correct treatment is still unclear. We present a therapeutic approach to be applied in selected patients.

1st Evidence-based Italian consensus conference on cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal carcinosis from ovarian cancer.

Ovarian cancer (OC) remains relatively rare, although it is among the top 4 causes of cancer death for women younger than 50. The aggressive nature of the disease and its often late diagnosis with peritoneal involvement have an impact on prognosis. The current scientific literature presents ambiguous or uncertain indications for management of peritoneal carcinosis (PC) from OC, both owing to the lack of sufficient scientific data and their heterogeneity or lack of consistency. Therefore, the Italian Society of Surgical Oncology (SICO), the Italian Society of Obstetrics and Gynaecology, the Italian Association of Hospital Obstetricians and Gynaecologists, and the Italian Association of Medical Oncology conducted a multidisciplinary consensus conference (CC) on management of advanced OC presenting with PC during the SICO annual meeting in Naples, Italy, on September 10-11, 2015. An expert committee developed questions on diagnosis and staging work-up, indications, and procedural aspects for peritonectomy, systemic chemotherapy, and hyperthermic intraperitoneal chemotherapy for PC from OC. These questions were provided to 6 invited speakers who answered with an evidence-based report. Each report was submitted to a jury panel, representative of Italian experts in the fields of surgical oncology, gynecology, and medical oncology. The jury panel revised the reports before and after the open discussion during the CC. This article is the final document containing the clinical evidence reports and statements, revised and approved by all the authors before submission.

Cytoreduction (Peritonectomy Procedures) Combined with Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Advanced Ovarian Cancer: Retrospective Italian Multicenter Observational Study of 511 Cases.

PURPOSE: The aim of this study was to help with the process of selecting patients with advanced ovarian cancer to undergo cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) by analyzing outcome data at distinct clinical time points reflecting the natural history of the disease. METHODS: In a retrospective Italian multicenter study investigating patients with advanced ovarian cancer who underwent CRS plus HIPEC between 1998 and 2014, we analyzed data for consecutive patients at eight treatment time points: primary debulking surgery (PDS); interval debulking surgery after partial response, after no response, and after a pathologic complete response to neoadjuvant chemotherapy; first recurrence with a progression-free interval >12, <12 months, or >12 months in patients who underwent further chemotherapy before CRS and HIPEC; and patients who underwent two or more CRS procedures and chemotherapy lines before CRS and HIPEC. RESULTS: The 511 enrolled patients underwent 3373 procedures; 72.6% achieved complete cytoreduction, with an overall major morbidity of 17.4%. At a median follow-up of 53.8 months, overall survival (OS) was 54.2 months (95% confidence interval [CI] 44-58.4) and progression-free (PFS) survival was 16.6 months (95% CI 14.7-19.1). Outcome analysis in patients in whom CRS plus HIPEC was used for primary advanced cancer or recurrent ovarian cancer showed significant differences in OS and PFS according to the time points analyzed. Multivariate analysis identified completeness of CRS, Peritoneal Cancer Index, and the times when patients underwent CRS plus HIPEC as independent prognostic factors. CONCLUSIONS: This selective information on survival should help in interpreting the findings from ongoing randomized studies focusing on CRS plus HIPEC in patients with advanced ovarian cancer.

Iterative procedures combining cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for isolated peritoneal recurrence.

PURPOSE: The aim of this study was to analyse feasibility, morbidity and outcome of repeat complete cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC). CRS combined with HIPEC is becoming the gold standard treatment for resectable peritoneal carcinomatosis in highly selected patients. As yet treatment of isolated peritoneal recurrence with iterative CRS and HIPEC has not been thoroughly explored. MATERIALS AND METHODS: We selected 16 patients presenting isolated peritoneal recurrence who had undergone iterative CRS and HIPEC from a dataset of 322 CRS associated with HIPEC performed between 1996 and 2012. RESULTS: Peritoneal carcinomatosis (PC) was due to colorectal and ovarian cancer, peritoneal mesothelioma and pseudomyxoma peritonei (PMP). Disease-free survival (DFS) was 13 months after the first procedure and 13.7 months after the second one. Overall morbidity rate was 43.7% (7/16) for all patients, with grade III-IV complications in three patients (18.7%). CONCLUSIONS: Iterative procedures combining cytoreductive surgery and HIPEC are feasible with acceptable morbidity and mortality rates in strictly selected patients. DFS following repeated CRS and HIPEC is comparable to that registered after the first procedure.

Treatment of peritoneal carcinomatosis from colonic cancer by cytoreduction, peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC). Experience of ten years.

INTRODUCTION: Peritoneal carcinomatosis (PC) is one of the routes of dissemination of abdominal neoplasms and is generally considered a lethal disease, with a poor prognosis by conventional chemotherapeutic treatments. While systemic chemotherapy has little impact on the treatment of peritoneal disease, some centers have reported encouraging results with cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC). This approach is based on surgical cytoreduction of the primary tumour, peritonectomy (stripping of implants on the peritoneal surface) and HIPEC. The rationale of this treatment, after macroscopic disease removal, is to obtain an elevated and persistent drug concentration in the peritoneal cavity, with limited systemic effects. Many studies have reported encouraging results on overall survival (OS) and the disease-free interval in patients affected by PC. PATIENTS AND METHODS: From October 1997 to November 2008, 411 operations for PC were performed in our institution; in 232 cases, cytoreduction plus HIPEC was carried out. Out of 72 operations for colonic cancer: 40 cytoreductions plus HIPEC, 12 cytoreductions+ EPIC (early postoperative intraperitoneal chemotherapy) and 16 debulking or explorative laparoscopies/laparotomies were performed. For the present study, the 40 patients who had undergone cytoreduction plus HIPEC for PC of colorectal cancer (CRC) were considered. RESULTS: The complication rate was 55% (22/40) and mortality rate 2.5% (1/40). The specific features of both groups were considered for the survival curves and complication rates, with special reference to the peritoneal carcinomatosis index (PCI; range 0, absence of disease to 39) and completeness of cytoreduction score (CCR; 0, no residual tumor, to CCR 3, residual nodules greater than 25 mm). In Group A, patients operated on prior to 2002, the median survival time was 16.7 months compared to 24.6 months for Group B, those operated on after 2002. The poor survival of Group A seemed to be related to higher PCI and CCR scores. CONCLUSION: Correct patient selection based on a maximum PCI of 16, associated with complete cytoreduction (CCR-0), produced encouraging results in our experience. To improve this encouraging survival outcome, it is very important to unify the surgical experience of expertise centres. Our results also suggest the need for an integrated approach to this condition to identify the correct aspect of the surgical domain and results that may be influencing the prognosis and the evolution of this patients.

Management of pseudomyxoma peritonei by cytoreduction+HIPEC (hyperthermic intraperitoneal chemotherapy): results analysis of a twelve-year experience.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare peritoneal carcinomatosis, characterized by a slowly progressive disease process with a large amount of mucus containing occasional epithelial cells. PMP is histologically classified into disseminated peritoneal adenomucinosis (DPAM), peritoneal mucinous carcinomatosis (PMCA) and an intermediate or discordant feature group (ID). Recent studies have shown that most cases of PMP originate from ruptured appendiceal tumors with progressive dissemination in the peritoneal cavity of mucin-producing epithelial cells. Encouraging results in the treatment of PMP have been reported by surgical cytoreduction of the primitive cancer, peritonectomy (stripping of implants on the peritoneal surface) and intraperitoneal hyperthermic chemoperfusion (HIPEC). In recent trials, this combined approach has been proposed as the standard treatment for PMP. PATIENTS AND METHODS: In this study, the results of twelve years single-institution experience on 60 consecutive patients affected by PMP, treated by cytoreductive surgery and the original semi-closed HIPEC technique are reported with special reference to overall survival (OS) and progression-free survival (PFS). RESULTS: The postoperative morbidity rate was 45% (27 patients); surgical morbidity was observed in 19 patients and medical complications in 9 cases. No postoperative deaths were observed. The survival data, 53 patients were analized (the last 7 were considered only for the complications rate, postoperative mortality and cancer features, not for OS or PFS because they were too recent for evaluation). At the final follow-up of the 53 patients, five and ten years OS were respectively 94% and 84.6% . DFS was 80% and 70% at five and ten years respectively. The follow-up data indicated that the survival probability may be good in patients with hystological type appendicular adenoma optimally cytoreduced (CCR-0). Interestingly if preoperative chemotherapy was performed represented a negative prognostic factor with statistically significant impact both on OS and DFS. CONCLUSION: As in other similar studies, cytoreductive surgery plus HIPEC, even when combined with an aggressive surgical procedure, is associated with an acceptable risk of postoperative complications and mortality. This combined treatment results in DFS and OS rates that are not described in the literature for surgery associated with systemic chemotherapy and, in our opinion, may be considered the gold standard treatment for this rare tumor.

Cytoreduction and hyperthermic intraperitoneal chemotherapy in the treatment of peritoneal carcinomatosis from pseudomyxoma peritonei.

AIM: To investigate the most important aspects of hyperthermic intraperitoneal chemotherapy (HIPEC) that has been accepted as the standard treatment for pseudomyxoma peritonei (PMP), with special regard to morbidity, overall survival (OS) and disease free survival (DFS) over 10 years. METHODS: Fifty-three patients affected by PMP underwent cytoreduction (CCR) and HIPEC with a "semi-closed" abdomen technique in our institution. The peritonectomy procedure and completeness of CCR were classified according to Sugarbaker criteria. Preoperative evaluation always included thoracic and abdominal CT scan to stage peritoneal disease and exclude distant metastases. Fifty-one patients in our series were treated with a protocol based on administration of cisplatinum 100 mg/m(2) plus mitomycin C 16 mg/m(2), at a temperature of 41.5 degrees centigrade for 60 min. Anastomoses were always performed at the end of HIPEC. The mean duration of surgery was 12 h including HIPEC. Continuous monitoring of hepatic and renal functions and hydroelectrolytic balance was performed in the postoperative period. RESULTS: Twenty-four patients presented with postoperative complications: surgical morbidity was observed in 16 patients and 6 patients were re-operated. All complications were successfully treated and no postoperative deaths were observed. Risk factors for postoperative morbidity were considered to be gender, age, body surface, duration of surgery, Peritoneal Cancer Index (PCI) and tumor residual value (CC score). No statistically significant correlation was found during the multivariate analysis: only the CC score was statistically significant. The OS in our experience was 81.8%, with a DFS of 80% at 5 years and of 70% at 10 years. CONCLUSION: In our experience, even if HIPEC combined with cytoreductive surgery involves a high risk of morbidity, postoperative complications can be resolved favorably in most cases with correct patient selection and adequate postoperative care, thus minimizing mortality. The association of CCR and HIPEC can be considered as the standard treatment for PMP. The OS and DFS results confirm the validity of this combined approach for the treatment of this rare neoplasm. The impact of preoperative chemotherapy on OS, in our opinion, is due to a major aggressiveness of tumors in treated patients.