Prognostic value of specific KRAS mutations in patients with colorectal peritoneal metastases.

BACKGROUND: There is little evidence on KRAS mutational profiles in colorectal cancer (CRC) peritoneal metastases (PM). This study aims to determine the prevalence of specific KRAS mutations and their prognostic value in a homogeneous cohort of patients with isolated CRC PM treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. MATERIALS AND METHODS: Data were collected from 13 Italian centers, gathered in a collaborative group of the Italian Society of Surgical Oncology. KRAS mutation subtypes have been correlated with clinical and pathological characteristics and survival [overall survival (OS), local (peritoneal) disease-free survival (LDFS) and disease-free survival (DFS)]. RESULTS: KRAS mutations occurred in 172 patients (47.5%) out of the 362 analyzed. Two different prognostic groups of KRAS mutation subtypes were identified: KRASMUT1 (G12R, G13A, G13C, G13V, Q61H, K117N, A146V), median OS > 120 months and KRASMUT2 (G12A, G12C, G12D, G12S, G12V, G13D, A59E, A59V, A146T), OS: 31.2 months. KRASMUT2 mutations mainly occurred in the P-loop region (P < 0.001) with decreased guanosine triphosphate (GTP) hydrolysis activity (P < 0.001) and were more frequently related to size (P < 0.001) and polarity change (P < 0.001) of the substituted amino acid (AA). When KRASMUT1 and KRASMUT2 were combined with other known prognostic factors (peritoneal cancer index, completeness of cytoreduction score, grading, signet ring cell, N status) in multivariate analysis, KRASMUT1 showed a similar survival rate to KRASWT patients, whereas KRASMUT2 was independently associated with poorer prognosis (hazard ratios: OS 2.1, P < 0.001; DFS 1.9, P < 0.001; LDFS 2.5, P < 0.0001). CONCLUSIONS: In patients with CRC PM, different KRAS mutation subgroups can be determined according to specific codon substitution, with some mutations (KRASMUT1) that could have a similar prognosis to wild-type patients. These findings should be further investigated in larger series.

PIPAC nebulizer: How to test the new devices in the market, expert recommendations.

Pressurized intraperitoneal aerosol chemotherapy, named PIPAC, is now used in many centers around the world and as an intraperitoneal drug delivery system for treatment of peritoneal carcinomatosis. Recently, many of us have encountered problems during PIPAC procedures due to changes in material and production features of the original PIPAC nebulizer. Concomitantly, new PIPAC nebulizers proposed by other manufacturers are being launched on the market; which claim that they are the same as the original device in delivering PIPAC. However, these new devices are all different in terms of materials, technical characteristics and costs. We have considered that, to maintain the acquired results of PIPAC, we must ensure that the new systems are equivalent. The characteristics deemed essential by the expert group are as follows: 1: The nebulizer must be able to create droplets through an injector pressure between 10 and 20 bars, 2: The mean droplet size must be 3 micrometers, with 95% of the droplets between 0 and 10 micrometers, 3: The diffusion angle must be 70 degrees, which is the minimum.

Secondary cytoreductive surgery, hyperthermic intraperitoneal intraoperative chemotherapy, and chemotherapy alone: a retrospective comparison of alternative approaches in relapsed platinum sensitive ovarian cancer.

INTRODUCTION: The best treatment for relapsed platinum sensitive epithelial ovarian cancer (EOC) is controversial. The aim of the study was to compare progression-free survival (PFS) and overall survival (OS) in platinum-sensitive EOC patients treated with chemotherapy alone (CTA), secondary cytoreductive surgery (SCR) or SCR plus hyperthermic intraperitoneal intraoperative chemotherapy (HIPEC). MATERIALS AND METHODS: Retrospective analysis of the clinical outcome of 46 EOC patients with at least 30 months of follow-up. RESULTS: Median follow-up time was 32 months for the CTA group, 30 months for the SCR group, and 45 months for the SCR + HIPEC group. Fifteen recurrences were observed in the CTA group, seven in the SCR group, and 16 in the SCR + HIPEC group. The median time elapsed between first and second recurrence (PFI-2) was significantly higher among patients treated with SCR + HIPEC, in comparison with patients treated with CTA (p = 0.012 andp = 0.017, respectively). On the contrary, PFI-2 did not significantly differ between the SCR and SCR + HIPEC groups (p = 0.877). A statistically significant difference in OS favouring SCR + HIPEC in comparison with CTA (p = 0.04) was observed. CONCLUSIONS: SCR HIPEC compared with CTA improves PFI-2 in patients with platinum-sensitive EOC recurrence. SCR + HIPEC might also improve OS in comparison with CTA. No improvement in favor of SCR + HIPEC vs SCR was observed,. These results further support the need of a randomized trial comparing chemotherapy with SCR ± HIPEC in this setting.

Contamination risk for operators performing semi-closed HIPEC procedure using cisplatin.

AIMS: Aim of this study was to assess operators' safety while performing a semi-closed HIPEC procedure for peritoneal carcinomatosis using cisplatin drugs. METHODS: Environmental air, theater personnel urine, operators' gloves and hand skin contamination were assessed during two non-consecutive working days. Six operating surgeons, two anesthesiologists and two theater nurses were included in the study. Glove samples were collected from the inner surface of the external glove and from the external surface of the inner glove from operating surgeons wearing a double pair of gloves. Personnel urine samples were collected before, after and 24 h from the procedure. RESULTS: Air and urine samples permanently resulted below detectable levels for cisplatin presence on all the tested sources and sessions. Cisplatin contamination was detected on the inner surface of the external gloves and on the outer surface of the inner gloves, but in a lower concentration for the latter. Skin wipe samples were below detectable levels for platinum presence. CONCLUSION: The results suggest that two pairs of gloves are adequate to protect the skin from antiblastic drugs. No sign of direct contact or systemic absorption of drugs was ever detected from the inspected samples. Semi-closed HIPEC technique appears to be a safe procedure for operators.

Treatment of diffuse malignant peritoneal mesothelioma (DMPM) by cytoreductive surgery and HIPEC.

AIM: Diffuse malignant peritoneal mesothelioma (DMPM) is a rare and locally aggressive tumor with poor prognosis, related in most cases to asbestos exposure. It is increasing in frequency, but currently no standard therapy is available. The biology of this disease is still poorly understood. Several highly specialized centers have recently reported improved survival by means of an innovative local-regional approach. The purpose of this article is to evaluate the survival benefit and the morbidity rate of patients affected by DMPM treated at our institution by cytoreductive surgery (CRS) associated with hyperthermic intraperitoneal perioperative chemotherapy (HIPEC). METHODS: This study includes 42 patients affected by DMPM treated by an uniform approach consisting of cytoreductive surgery associated with HIPEC using cisplatin and doxorubicin. The primary end point was overall survival and morbidity rate. The secondary end point was evaluation of prognostic variables for overall survival. RESULTS: The median follow-up period was 72 months (range 1-235 months). Thirty-five patients (83.3%) presented epithelial tumors and 7 were affected by multicystic mesothelioma. The mean peritoneal cancer index (PCI) was 13. Thirty-eight patients (90.4%) had complete cytoreduction (CC-0/1). The overall morbidity rate was 35.7% associated to a perioperative mortality of 7.1%. Median overall survival rate was 65 months with a 1- and 5-year survival rates of 63% and 44%, respectively. CONCLUSION: The treatment of DMPM by CRS+HIPEC in selected patients is a feasible technique that allows to achieve encouraging results in terms of overall survival rate, with an acceptable morbidity rate. Further investigations are needed to clarify the role and the timing of this promising technique.

Treatment of peritoneal carcinomatosis from ovarian cancer by surgical cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC).

AIM: Ovarian cancer may be considered as an "intraperitoneal disease" by itself. When surgical removal associated with systemic chemotherapy fails, usually, the history of the patients is characterized by poor prognosis. Some encouraging results have been reported by the treatment of peritoneal carcinomatosis (PC) from ovarian cancer by complete surgical cytoreduction, peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC). The purpose of this article was to evaluate the survival benefit and the morbidity of patients with ovarian cancer treated at our institution by cytoreductive surgery associated with hyperthermic intraperitoneal perioperative chemotherapy (HIPEC). METHODS: Between October 1995 and December 2012 more than 600 operations for PC were performed; in 308 cases surgical cytoreduction associated with HIPEC was carried out. Eighty-five patients treated by cytoreduction associated with HIPEC were affected by recurrent epithelial ovarian cancer (EOC). Statistical analysis was performed on 70 patients (last 15 patients were too recent for evaluation). Two trials were applied: 1) patients presenting first peritoneal relapse after surgery and systemic chemotherapy (CT), 6 months later from last CT administration; 2) multiple relapse patients. RESULTS: On 70 patients, morbidity and mortality rates were 35.7% and 7.1%, respectively. Overall median survival was 42.0 months, but in primary EOC was 48.0 months and in recurrent EOC was 28 months (P=0.12). Statistical analysis revealed that the completeness of cytoreduction was the most statistically significant factor related to survival: in completely citoreduced patients, overall survival was 48 months. CONCLUSION: Citoreductive surgery associated to platinum compounds HIPEC is feasible and relatively safe in recurrent and primary PC from ovarian cancer. Better selection of patients and second-look surgery in high risk-patients have to be investigated to improve those encouraging results.

Treatment of peritoneal carcinomatosis from colonic cancer by cytoreduction, peritonectomy and HIPEC: preliminary results in highly selected patients.

AIM: Peritoneal carcinomatosis (PC) is one of the routes of spread 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 on overall survival (OS) and disease-free survival (DFS) with surgical cytoreduction associated with hyperthermic intraperitoneal chemotherapy (HIPEC). The purpose of this article is to evaluate the survival benefit and the morbidity in patients affected by colorectal PC treated at our institution by cytoreductive surgery associated with HIPEC. METHODS: In our institution, from October 1995 to June 2012, about 550 operations for PC were performed; in 300 cases cytoreduction plus HIPEC was carried out. Out of 90 operations for colonic cancer: 50 cytoreduction plus HIPEC, 12 cytoreduction and EPIC (early postoperative intraperitoneal chemotherapy) and 28 debulking or explorative laparoscopies/laparotomies were performed. For the present study, 50 patients who had undergone cytoreduction and HIPEC for PC of colorectal cancer origin (CRC) were considered. RESULTS: The morbidity and mortality rates were 34% (17/50) and 2% (1/50), respectively. The patients were divided in two groups according to PCI (peritoneal cancer index, range 0-39) and CC score (completeness of cytoreduction): in Group A (23 patients, PCI>16, CC-2) the median survival time was 15 months compared to 48.1 months for Group B (27 patients, PCI≤16, CC-0/1). The poor survival of Group A seemed to be related to higher PCI and CC score. CONCLUSION: Patient selection based on a maximum PCI of 16 associated with a complete cytoreduction (CC-0) produced encouraging results.

Treatment of pseudomyxoma peritonei with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC): a single center experience.

AIM: Pseudomyxoma peritonei (PMP) is a rare form of peritoneal carcinomatosis characterized by abnormal quantity of extracellular mucinous material. It almost originates from a primary appendiceal tumor with different malignancy degrees. The purpose of this study was to evaluate outcome and long-term survival on 80 patients affected by PMP after cytoreductive surgery (CRS) associated with hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: From October 1995 to June 2012, about 550 operations for PC were performed; in 300 cases surgical cytoreduction in association with HIPEC was carried out. Regarding PMP, 80 procedures of CRS and HIPEC were performed. This approach is based on surgical removal of the primitive cancer, peritonectomy (stripping of implants on the peritoneal surface) and HIPEC performed with cisplatinum and C mytomicin. The rationale of this treatment is to obtain, after macroscopic disease removal, an elevated and persistent drug concentration in the peritoneal cavity, with limited systemic effects. RESULTS: The complication rate was 52.5% (42/80) with no postoperative deaths. The median overall and progression-free survival were 144 and 88 months, respectively. Not complete cytoreductive surgery (P<0.001), tumor histology (P=0.02) and previous systemic chemotherapy (p = 0.03) were identified in the univariate analysis as independent predictors for a poorer long-term survival. In the multivariate analysis, the completeness of cytoreduction was the only significant variable influencing the outcome. Incomplete cytoreduction (P<0.01) resulted the only statistically significant variable associated with a higher incidence of postoperative complications. CONCLUSION: PMP can be treated with curative intent in a large percentage of cases by cytoreductive surgery associated with HIPEC. This new approach could be performed safely with acceptable morbidity and mortality in selected patients treated in specialized centers. Completeness of cytoreduction allows to achieve the best results.