Peritoneal Spread of Low-grade Appendiceal Tumours - 2 Days of Early Postoperative Intra-peritoneal Chemotherapy Are Enough.

BACKGROUND/AIM: While controversial, cytoreductive surgery (CRS) with heated intra-peritoneal chemotherapy (HIPEC) and early postoperative intra-peritoneal chemotherapy (EPIC) remains the mainstay of treatment for low grade appendiceal neoplasm with pseudomyxoma peritonei (PMP). Our study aimed to investigate the difference in survival when administering HIPEC alone vs. HIPEC + EPIC. Additionally, we examined whether the duration of EPIC affects survival. PATIENTS AND METHODS: We compared the difference in survival in 238 patients who underwent CRS + HIPEC alone vs. CRS + HIPEC/EPIC combination for low grade appendiceal cancer. We also compared short course (1-2 days) vs. long course (3-5 days) of EPIC. RESULTS: HIPEC/EPIC combination group (n=179) showed a significantly better 5-year survival of 95% compared to 71% in HIPEC alone (n=59). There was no statistically significant difference in 5-year survival between short course (n=22) and long course of EPIC (n=157). CONCLUSION: Combined use of HIPEC and EPIC improves 5-year survival in low-grade appendiceal neoplasm. Two days of EPIC are sufficient.

Nomogram to predict overall survival of patients with pseudomyxoma peritonei of appendiceal origin: A retrospective cohort study.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare disease, with the rate of overall survival (OS) influenced by many factors. The present study aimed to define independent predictors and establish a nomogram for individual risk prediction in PMP patients. METHODS: One hundred forty-seven PMP patients were consecutively included between June 1, 2013, and November 22, 2019. The log-rank test was used to compare the OS rate between groups; subsequently, variables with p < .10 were subjected to multivariate Cox modeling for defining independent prediction indicators. Finally, a nomogram was established based on independent prognosticators and assessed for internal validation. RESULTS: Multivariate Cox analysis showed that D-dimer level, carbohydrate antigen (CA) 125 level, CA 19-9 level, degree of radical surgery, and histological grade were all independently associated with OS in PMP patients. A nomogram was plotted and underwent internal validation. The discrimination ability of the nomogram revealed a good predictive ability as indicated by the C-index value (0.825), and calibration plots confirmed good consistency between the predicted and observed survival probabilities. CONCLUSIONS: Five independent prognostic factors for predicting the survival of PMP patients were identified, and the nomogram based on these independent indicators showed a reasonable discrimination ability for individual risk prediction.

Twenty-years' experience with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for pseudomyxoma peritonei (PMP).

PURPOSE: Pseudomyxoma peritonei is treated with cytoreductive surgery (CRS) combined and hyperthermic intraoperative intraperitoneal chemotherapy (HIPEC). The purpose of this study was to report the20-year experience of one surgical team inCRS and HIPEC for PMP of appendiceal origin. METHODS: Retrospective study of the files of patients with PMP of appendiceal origin that underwent CRS+HIPEC. Morbidity and hospital mortality were recorded. Clinical and histopathologic variables were correlated to survival and recurrence. RESULTS: The files of 41 patients with PMP of appendiceal origin that underwent CRS+HIPEC from 1999-2018 were retrieved. The mortality and the morbidity rates were 2.4% and 29.3%, respectively. The 5- and 8-year survival rate was 68.3%. The completeness of cytoreduction, and the extent of previous surgery were identified as the prognostic indicators of survival. The recurrence rate was 32.5% with the completeness of cytoreduction, the histologic type of the tumor being the prognostic indicator. CONCLUSIONS: CRS in combination with perioperative intraperitoneal chemotherapy is a safe and effective treatment in the management of PMP of appendiceal origin.

The Role of Hyperthermic Intraperitoneal Chemotherapy in Pseudomyxoma Peritonei After Cytoreductive Surgery.

Importance: Studies on the prognostic role of hyperthermic intraperitoneal chemotherapy (HIPEC) in pseudomyxoma peritonei (PMP) are currently not available. Objectives: To evaluate outcomes after cytoreductive surgery (CRS) and HIPEC compared with CRS alone in patients with PMP. Design, Setting, and Participants: This cohort study analyzed data from the Peritoneal Surface Oncology Group International (PSOGI) registry, including 1924 patients with histologically confirmed PMP due to an appendiceal mucinous neoplasm. Eligible patients were treated with CRS with or without HIPEC from February 1, 1993, to December 31, 2017, and had complete information on the main prognostic factors and intraperitoneal treatments. Inverse probability treatment weights based on the propensity score for HIPEC treatment containing the main prognostic factors were applied to all models to balance comparisons between the CRS-HIPEC vs CRS-alone groups in the entire series and in the following subsets: optimal cytoreduction, suboptimal cytoreduction, high- and low-grade histologic findings, and different HIPEC drug regimens. Data were analyzed from March 1 to June 1, 2018. Interventions: HIPEC including oxaliplatin plus combined fluorouracil-leucovorin, cisplatin plus mitomycin, mitomycin, and other oxaliplatin-based regimens. Main Outcomes and Measures: Overall survival, severe morbidity (determined using the National Cancer Institute Common Terminology for Adverse Events, version 3.0), return to operating room, and 30- and 90-day mortality. Differences in overall survival were compared using weighted Kaplan-Meier curves, log-rank tests, and Cox proportional hazards multivariable models. A sensitivity analysis was based on the E-value from the results of the main Cox proportional hazards model. Differences in surgical outcomes were compared using weighted multivariable logistic models. Results: Of the 1924 patients included in the analysis (997 [51.8%] men; median age, 56 [interquartile range extremes (IQRE), 45-65] years), 376 were in the CRS-alone group and 1548 in the CRS-HIPEC group. Patients with CRS alone were older (median age, 60 [IQRE, 48-70] vs 54 [IQRE, 44-63] years), had less lymph node involvement (14 [3.7%] vs 119 [7.7%]), received more preoperative systemic chemotherapy (198 [52.7%] vs 529 [34.2%]), and had higher proportions of high-grade disease (179 [47.6%] vs 492 [31.8%]) and suboptimal cytoreduction residual disease (grade 3, 175 [46.5%] vs 117 [7.6%]). HIPEC was not associated with a higher risk of worse surgical outcomes except with mitomycin, with higher odds of morbidity (1.99; 95% CI, 1.25-3.19; P = .004). HIPEC was associated with a significantly better overall survival in all subsets (adjusted hazard ratios [HRs], 0.60-0.68, with 95% CIs not crossing 1.00). The weighted 5-year overall survival was 57.8% (95% CI, 50.8%-65.7%) vs 46.2% (95% CI, 40.3%-52.8%) for CRS-HIPEC and CRS alone, respectively (weighted HR, 0.65; 95% CI, 0.50-0.83; P < .001; E-value, 2.03). Such prognostic advantage was associated with oxaliplatin plus fluorouracil-leucovorin (HR, 0.42; 95% CI, 0.19-0.93; P = .03) and cisplatin plus mitomycin (HR, 0.57; 95% CI, 0.42-0.78; P = .001) schedules. Conclusions and Relevance: In this cohort study, HIPEC was associated with better overall survival when performed after CRS in PMP, generally without adverse effects on surgical outcomes.

Development and validation of prognostic nomograms for pseudomyxoma peritonei patients after surgery: A population-based study.

BACKGROUND: The aim of study was to develop and validate nomograms for predicting overall survival (OS) and cancer-specific survival (CSS) of patients with pseudomyxoma peritonei (PMP) and compare the predictive accuracy with the American Joint Committee on Cancer (AJCC) staging system. METHODS: Data of 4959 PMP patients who underwent surgical resection were collected between 2004 and 2015 from the Surveillance Epidemiology and End Results (SEER) database. All included patients were divided into training (n = 3307) and validation (n = 1652) cohorts. The Kaplan-Meier method and Cox proportional hazard model were applied. Nomograms were validated by discrimination and calibration. Finally, concordance index (C-index) was used to compare the predictive performance of nomograms with that of the AJCC staging system. RESULTS: According to the univariate and multivariate analyses of training sets, both nomograms for predicting OS and CSS combining age, grade, location, N stage, M stage, and chemotherapy were identified. Nomograms predicting OS also incorporated T stage and the number of lymph nodes removed (LNR). The calibration curves showed good consistency between predicted and actual observed survival. Moreover, C-index values demonstrated that the nomograms predicting both OS and CSS were superior to the AJCC staging system in both cohorts. CONCLUSION: We successfully developed and validated prognostic nomograms for predicting OS and CSS in PMP patients. Two nomograms were more accurate and applicable than the AJCC staging system for predicting patient survival, which may help clinicians stratify patients into different risk groups, tailor individualized treatment, and accurately predict patient survival in PMP.

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in pseudomyxoma peritonei of appendiceal origin: result of a single centre study.

Pseudomyxoma peritonei (PMP) is a rare condition characterized by the intraperitoneal accumulation of mucus derived mostly by appendiceal mucinous neoplasm. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) can offer a favourable overall survival. In this study, we report a single-institute outcomes following CRS and HIPEC in patients with this condition. This is a review of prospectively collected data from 32 patients (11 men and 21 women) affected by PMP of appendiceal origin who underwent CRS and HIPEC from 2008 to 2016 in our Surgical Unit of General and Esophagogastric Surgery. The median age of the patients was 53 years (range 25-77 years). After CRS, all patients underwent HIPEC (mytomicin C 3.3 mg/m2/L and cisplatin 25 mg/m2/L at 41 °C for 60 min) with closed abdomen technique. The median (range) follow-up time for surviving patients was 43 (18-119) months. The median peritoneal cancer index (PCI) was 17. Complete cytoreductive surgery (CC0) was achieved in in 22 patients (69%). The majority of patients (88%) had grade I-II complications, 3 (9%) had grade III complications, and 1 (3%) patient had a grade IV complication. There were no perioperative mortalities. The median hospital stay was 9.5 (range 9-24) days. One year and 5-year overall survival (OS) were 90% and 58%, respectively. Regardless of histotype, disease-free survival was 95% at 1 year and 46% at 5 years. CRS in combination with HIPEC is a feasible treatment strategy and can achieve a satisfactory outcome in patients with PMP of appendiceal origin.

Pathological prognostic factors of pseudomyxoma peritonei: comprehensive clinicopathological analysis of 155 cases.

BACKGROUND: Pseudomyxoma peritonei (PMP) is an extremely rare malignancy, characterized by extensive peritoneal implantation and colloidal ascites. This study was to explore the pathological prognostic factors of PMP. METHODS: Specimens from 155 PMP patients were analyzed by H&E and immunohistochemistry. Parameters included primary tumor location, histological grade, lymph node metastasis, tumor emboli in the blood and lymph vessels, perineural invasion, Ki67 labeling index, p53, mismatch repair (MMR) gene mutations, MUC1, MUC2, MUC5AC, and MUC6. Clinicopathological and follow-up data were subjected to univariate and multivariate analyses. RESULTS: The patients included 63.2% (n = 98) low-grade mucinous carcinoma peritonei, 31.6% (n = 49) high-grade mucinous carcinoma peritonei and 5.2% (n = 8) high-grade mucinous carcinoma peritonei with signet ring cells. There were 9.7% (n = 15) with lymph node metastasis; 11.6% (n = 18) with angiolymphatic invasion; 6.3% (n = 8) with defective MMR (dMMR); 35.5% (n = 55) with Ki67 labeling index ≥ 50%; 36.1% (n = 56) with p53 mutation. For PMP from appendiceal origin (n = 140), univariate analysis identified 10 potential prognostic factors. But Multivariate analysis identified only histologic grade was the independent prognostic factor for OS. Mortality risk of high-grade peritoneal mucinous carcinoma or high-grade peritoneal mucinous carcinoma with signet ring cells was 7.056 times (P < .0001, 95% CI: 2.701-18.435) or 27.224 times (P < .0001, 95% CI: 6.207-119.408), respectively, higher than low-grade. CONCLUSIONS: For PMP from the appendiceal origin, histological grade could be the only independent prognostic factor.

Efficacy of modified FOLFOX6 chemotherapy for patients with unresectable pseudomyxoma peritonei.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare malignancy, and there is insufficient evidence about systemic chemotherapy for this disease. METHODS: We retrospectively evaluated the efficacy and safety of a chemotherapeutic regimen with 5-fluorouracil and oxaliplatin (modified FOLFOX6, mFOLFOX6) for patients with unresectable pseudomyxoma peritonei. Patients who received the therapy between April 2000 and February 2019 at the Department of Medical Oncology, Tohoku University Hospital, were enrolled in this study. RESULTS: Eight patients were treated with mFOLFOX6. The sites of primary tumor were appendix in six patients, ovary in a patient, and urachus in a patient. Six patients received surgery. Seven patients had histologically high-grade PMP, and one patient had low-grade PMP. The median follow-up duration was 27.2 months. All the patients had non-measurable regions as the targets of tumor response. Non-complete response or non-progressive disease was observed in seven patients, with a disease control rate of 87.5%. The median progression-free survival and overall survival were 13.0 months and 27.9 months, respectively. An obvious reduction in the symptoms was observed in two patients. Five patients experienced decline in the serum tumor markers, CEA or CA19-9. The grade 3/4 toxicity that was observed was grade 4 neutropenia in one patient and grade 3 neutropenia in two patients. CONCLUSIONS: mFOLFOX6 might be an effective and tolerable treatment option for patients with unresectable PMP. To our knowledge, this is the first case series of mFOLFOX6 in patients with unresectable PMP and the first case series of systemic chemotherapy for Asian patients with unresectable PMP.

Intraperitoneal mitomycin C improves survival compared to cytoreductive surgery alone in an experimental model of high-grade pseudomyxoma peritonei.

Pseudomyxoma peritonei (PMP) is a rare cancer commonly originating from appendiceal neoplasms that presents with mucinous tumor spread in the peritoneal cavity. Patients with PMP are treated with curative intent by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). The value of adding HIPEC to CRS has not been proven in randomized trials, and the objective of this study was to investigate the efficacy of intraperitoneal mitomycin C (MMC) and regional hyperthermia as components of this complex treatment. Xenograft tissue established from a patient with histologically high-grade PMP with signet ring cell differentiation was implanted intraperitoneally in 65 athymic nude male rats and the animals were stratified into three treatment groups; the cytoreductive surgery group (CRSG, CRS only), the normothermic group (NG, CRS and intraperitoneal chemotherapy perfusion (IPEC) with MMC at 35 ºC), and the hyperthermic group (HG, CRS and IPEC at 41 ºC). The main endpoints were survival and tumor weight at autopsy. Adequate imitation of the clinical setting and treatment approach was achieved. The median survival was 31 days in the CRSG, 60 days in NG and 67 days in HG. The median tumor weights at autopsy were 34 g in CRSG, 23 g NG and 20 g in HG. In conclusion, the addition of IPEC with MMC after CRS doubled the survival time and reduced tumor growth compared to CRS alone. Adding regional hyperthermia resulted in a modest improvement of treatment outcome.

Evaluation of cytoreductive surgery and HIPEC for peritoneal surface malignancies: analysis of 384 consecutive cases.

BACKGROUND: Peritoneal surface malignancy (PSM) was historically associated with a poor survival. The adoption of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) can now offer patients with PSM a favourable overall survival. Here, we report our single-institute outcomes following CRS and HIPEC for PSM and evaluate changes in our practice over time. METHODS: This is a retrospective review from 2009 to 2018 of all patients undergoing CRS and HIPEC for PSM at a statewide peritoneal disease centre. Cases were divided into the first half and second to compare changes in practice over time. RESULTS: Three hundred and eighty four CRS and HIPEC cases were performed during this time. The median age was 56 years with 59.6% female. The median peritoneal carcinomatosis index (PCI) was 11, with a reduction in PCI in the second cohort (9 v 15, p < 0.01). Complete cytoreduction rates were significantly higher in the second cohort (82.3% v 67.7%, p < 0.01). Overall, grade III/IV complications occurred in 101 cases (26.3%) with three (0.8%) perioperative mortalities. Median overall survival (OS) for the entire cohort was 85 months, with a 5-year survival of 52%. Median OS was 97 months for PMP, 34 months for colorectal peritoneal metastases and 27 months for other histologies. Completeness of cytoreduction, histology type, and PCI were factors independently associated with overall survival. CONCLUSION: CRS and HIPEC can offer highly favourable outcomes for PSM with low morbidity. Successful complete cytoreduction rates improved significantly with greater experience and better patient selection.

Factors influencing long-term survival after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei originating from appendiceal neoplasms.

Background: Pseudomyxoma peritonei (PMP) is a rare disease, most commonly of appendiceal origin. Treatment consists of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). The aim of this study was to identify prognostic factors for recurrence and survival. Methods: This was an observational study using a prospectively designed database containing consecutive patients with PMP originating from the appendix, undergoing CRS-HIPEC at a tertiary referral centre between 1996 and 2015. Histopathological slides were reassessed. Cox regression was used for multivariable analyses. Results: Of 225 patients identified, 36 (16·0 per cent) were diagnosed with acellular mucin, 149 (66·2 per cent) had disseminated peritoneal adenomucinosis (DPAM) and 40 (17·8 per cent) had peritoneal mucinous carcinomatosis (PMCA). The 5-year overall survival (OS) rates were 93, 69·8 and 55 per cent respectively. Recurrence was observed in 120 patients (53·3 per cent), 39 of whom (17·3 per cent) were treated with a second CRS-HIPEC procedure. Factors independently associated with poor disease-free survival were six or seven affected regions (hazard ratio (HR) 6·01, 95 per cent c.i. 2·04 to 17·73), incomplete cytoreduction (R2a resection: HR 1·67, 1·05 to 2·65; R2b resection: HR 2·00, 1·07 to 3·73), and more than threefold raised carcinoembryonic antigen (CEA) and/or carbohydrate antigen (CA) 19-9 level (HR 2·31, 1·30 to 4·11). Factors independently associated with poorer OS were male sex (HR 1·74, 1·09 to 2·77), incomplete cytoreduction (R2a resection: HR 1·87, 1·14 to 3·08; R2b resection: HR 2·28, 1·19 to 4·34), and more than threefold raised CEA and/or CA19-9 level (HR 2·89, 1·36 to 6·16). Conclusion: CEA and CA19-9 levels raised more than threefold above the upper limit identify patients with PMP of appendiceal origin and poorer survival.

Survival after complete cytoreductive surgery and HIPEC for extensive pseudomyxoma peritonei.

INTRODUCTION: The optimal treatment for pseudomyxoma peritonei (PMP) combines complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Yet, achieving CRS is challenging in the case of extensive involvement of the peritoneal cavity and the survival benefit in this setting remains uncertain. The present study evaluated the surgical outcomes according to the peritoneal extent. METHODS: Between 1992 and 2014, 245 patients underwent CRS and HIPEC for PMP in our institution. Their characteristics were reviewed using a prospective database. Extensive PMP was defined as a peritoneal cancer index (PCI) ≥ 28. Sixty-one patients with extensive PMP were compared to 184 with non-extensive PMP. RESULTS: Severe complications were more frequent in the extensive group (46% vs. 23%, p < 0.001) but the post-operative mortality was not significantly different (8% vs. 3%, p = 0.1). The 5-year disease-free survival reached 45% in the extensive and 78% in the non-extensive group (p < 0.0001). The 5-year overall survival was 70% and 90% in the extensive and non-extensive group respectively (p < 0.021). CONCLUSION: CRS with HIPEC offers prolonged survival even in the case of extensive PMP. Because of the high rate of surgical morbidity in the extensive group, patients should be carefully selected.

Recurrence of pseudomyxoma peritonei after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Background: Pseudomyxoma peritonei (PMP) is a rare clinical condition characterized by mucinous ascites, typically related to appendiceal or ovarian tumours. Current standard treatment involves cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), but recurrences occur in 20-30 per cent of patients. The aim of this study was to define the timing and patterns of recurrence to provide a basis for modifying follow-up of these patients. Methods: This observational study examined a prospectively developed multicentre national database (RENAPE working group) to identify patients with recurrence after optimal CRS and HIPEC for PMP. Postoperative complications, long-term outcomes and potential prognostic factors were evaluated. Results: Of 1411 patients with proven PMP, 948 were identified who had undergone curative CRS and HIPEC. Among these patients, 229 first recurrences (24·2 per cent) were identified: 196 (20·7 per cent) occurred within the first 5 years (early recurrence) and 30 (3·2 per cent) occurred between 5 and 10 years. Three patients developed a first recurrence more than 10 years after the original treatment. The mean(s.d.) time to first recurrence was 2·36(2·21) years. Preoperative chemotherapy and high-grade pathology were significant factors for early recurrence. Overall survival for the entire group was 77·9 and 63·1 per cent at 5 and 10 years respectively. The principal site of recurrence was the peritoneum. Conclusion: Recurrence of PMP was rare after 5 years and exceptional after 10 years.

Impact of a modified peritoneal cancer index using FDG-PET/CT (PET-PCI) in predicting tumor grade and progression-free survival in patients with pseudomyxoma peritonei.

OBJECTIVES: The peritoneal cancer index (PCI) is widely used for assessing pseudomyxoma peritonei (PMP) in surgery. The aim of this study was to evaluate the utility of a modified PCI using 18F-fluorodeoxyglucose (18F-FDG)-PET/CT (PET-PCI) for predicting pathologic grade and progression-free survival (PFS) in patients with PMP. METHODS: Thirty-five patients who underwent 18F-FDG-PET/CT before cytoreductive surgery and/or hyperthermic intraperitoneal chemotherapy were enrolled. PET-PCI was determined by summing up the visually scored 18F-FDG uptake of PMP lesions in 13 specific abdominal-pelvic regions. Uptake score was defined as 0, no lesion or lesion without uptake; 1, slight uptake less than or equivalent to mediastinal blood pool; 2, moderate uptake above mediastinal but below or equal to liver; and 3, intense uptake moderately to markedly higher than liver. SUVmax of the lesion was also evaluated. RESULTS: Pathologic diagnosis revealed 19 patients with low-grade PMP and 16 patients with high-grade PMP. Patients with high-grade PMP showed significantly higher PET-PCI and SUVmax than patients with low-grade PMP (PET-PCI 14.8 vs. 8.7, p = 0.007; SUVmax 3.6 vs. 2.6, p = 0.013). Using a cutoff PET-PCI of 12, Kaplan-Meier analyses showed a significant difference in PFS between patients with high and low PET-PCI (p < 0.001; hazard ratio (HR), 12.4). For SUVmax, the optimal cutoff was 2.7 and the correlation with PFS was also significant (p = 0.008; HR, 4.7). In multivariate Cox proportional-hazards regression, PET-PCI was independently and significantly correlated with PFS. CONCLUSIONS: PET-PCI can reflect histopathologic features and appears useful for predicting recurrence in patients with PMP. KEY POINTS: • Peritoneal cancer index using 18F-FDG-PET/CT (PET-PCI) has great potential for predicting progression-free survival in patients with pseudomyxoma peritonei. • PET-PCI provides higher prognostic performance than maximum standardized uptake value (SUVmax). • PET-PCI shows high correlation with histopathologic grade of pseudomyxoma peritonei.

Patient Survival after Surgical Management in Intrathoracic Pseudomyxoma peritonei.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare disease, characterized by mucinous ascites and deposits diffusely present on the peritoneal surfaces. However, extension of PMP to the thoracic cavity is extremely rare. Although there are a few case reports on the long-term postoperative prognosis of intrathoracic lesions, whether surgical resection of these lesions can improve patient prognosis remains unclear. METHODS: We reviewed 17 patients with PMP who underwent resection of intrathoracic lesions after abdominal cytoreductive surgery and examined their clinical outcome after surgery. RESULTS: Direct extension into the pleural cavity was identified in 11 patients. Extrapleural pneumonectomy of the lesions followed by hyperthermic intrathoracic chemotherapy (HITOC) was performed in four patients, parietal pleurectomy and visceral tumor resection followed by HITOC in four patients, resection of all disseminated pleural and visceral lesions followed by HITOC in one patient, resection of a single disseminated lesion in one patient, and composite resection of basal segment with the diaphragm in one patient. Pulmonary metastases were found in six patients. Partial resection was performed in four patients, segmentectomy in one patient, and lobectomy in one patient. We could perform macroscopic resection of the tumor in all the cases. The 5-year overall survival rate after thoracic surgery for the 17 patients was 46.1% and relapse-free survival was 34.9%. CONCLUSIONS: Resection of intrathoracic lesions of PMP after abdominal cytoreductive surgery achieved 5 years survival in at least 46.1% of the patients. Aggressive tumor resection should be considered for patients with PMP extending to thoracic cavity.

Cellularity in low-grade Pseudomyxoma peritonei impacts recurrence-free survival following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

PURPOSE: Documentation of cellularity in Pseudomyxoma peritonei (PMP) is not performed on a regular basis in everyday clinical practice, but is recommended by the PSOGI (Peritoneal Surface Oncology Group International). We investigated the impact of cellularity in PMP following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) on recurrence-free survival. METHODS: Data from 25 patients with low-grade (American Joint Committee on Cancer grade G1) PMP were retrospectively evaluated. Cellularity was categorized as acellular mucin, scant (< 2% cellularity), moderate (2-19% cellularity), or high cellularity (> 20% cellularity). Impact of cellularity, PCI, CC-score, and HIPEC regimen on recurrence-free and overall survival was primarily assessed. RESULTS: Assessment of cellularity showed acellular mucin in ten patients (40%), scant cellularity in 11 (44%) patients, moderate cellularity in one (4%) patient, and high cellularity in three (12%) patients. Median PCI was 15 (range, 1-39). A CC-0 score was achieved in 13 (52%) patients and a CC-1 score was achieved in 12 (48%) patients. After a median follow-up of 25 (range, 2-74) months, all patients were still alive. Overall, four (16%) patients suffered from recurrent disease after a median of 38 (range, 36-60) months. PCI above 17 (p = 0.03) and moderate and high cellularity (p = 0.007) were statistically significantly associated with recurrent disease. CC-score and HIPEC compound used did not impact on recurrence-free survival. CONCLUSIONS: Recurrent disease occurs more often in patients with PCI values above 17 and with moderate and high cellularity in low-grade PMP. Pathological assessment of cellularity is crucial for identification of patients at risk for recurrence.

Overall survival of pseudomyxoma peritonei and peritoneal mesothelioma patients after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy can be predicted by computed tomography quantified sarcopenia.

BACKGROUND: Malnutrition is associated with increased postoperative morbidity in abdominal surgery. This study aimed to determine if sarcopenia and/or abdominal fat composition could predict postoperative outcomes for patients undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) for pseudomyxoma peritonei (PMP) and peritoneal mesothelioma (PM). METHODS: All patients who underwent a complete CRS-HIPEC for PMP and PM, between January 2009 and September 2017, were retrospectively studied. Preoperative computed tomography (CT) was used to measure the cross-sectional surface of skeletal muscle mass and adipose tissue (visceral and subcutaneous), at the level of the third lumbar vertebrae, to assess for sarcopenia and abdominal fat composition. RESULTS: Among 115 patients, 82 were treated for PMP and 33 for PM. 64 patients (55.7%) were sarcopenic on the preoperative imagery. Major postoperative complications occurred in 63 patients (54.8%), without observable difference between sarcopenic and non-sarcopenic patients (56.2% vs. 52.9%; p = 0.723). The median overall survival (OS) was 73.3 for the patients with a normal muscle mass and 57.2 months for the sarcopenic patients (p = 0.05). CONCLUSION: CT measured sarcopenia is an independent predictive factor for overall survival in patients treated for PMP and PM with CRS-HIPEC, but cannot predict postoperative morbidity.

[Clinicopathologic characteristics of pseudomyxoma peritonei].

Objective: To analyze the relationship between clinicopathologic characteristics of pseudomyxoma peritonei (PMP) and its prognosis. Methods: Fifty-two cases of PMP collected from 2012 to 2017 at Beijing Shijitan Hospital, Capital Medical University were reviewed using the diagnostic criteria of WHO 2010. The histopathologic features, including original location, neural invasion and calcification were observed; and the relationship with prognosis was analyzed. Immunohistochemical staining for CK7, CK20 and CDX2 was performed on all cases. ER, PR, and p16 were additionally performed on those without clear origin. Results: Patients' mean age was 52.0 years, and included 29 males and 23 females. Thirty-two cases were derived from appendix; among them, 23 were low grade and 29 were high grade. Signet ring-cells, neural invasion and calcification were detected in 15, 12 and 9 cases respectively. Neural invasion was associated with adverse prognosis (P=0.025) and signet ring cell morphology (P<0.01). Prognosis was not related to gender, age, original location or grade. Conclusion: Neural invasion is not uncommon in PMP and predicts a bad prognosis.

The pre-operative neutrophil-lymphocyte ratio predicts overall and disease-free survival following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with pseudomxyoma peritonei of appendiceal origin.

AIM: The neutrophil-lymphocyte ratio (NLR) and other inflammation-based scores have been used as a prognostic tool to predict survival in solid tumours including pseudomyxoma peritonei (PMP). The aim was to evaluate the prognostic value of this marker and risk stratify PMP patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: Retrospective analysis was conducted of a prospectively collected database of patients with PMP who underwent CRS and HIPEC between 1994 and 2015. The NLR was calculated by dividing the pre-operative neutrophil count by lymphocyte count. Predicted overall survival (OS) and disease-free interval (DFI) were calculated using a Kaplan-Meier survival model. RESULTS: The study included 699 patients, stratified into four groups as defined by their NLR. Group A: 200 (28.6%) patients (NLR = 0.10-2.00), Group B: 160 (22.8%) patients (NLR = 2.10-2.78), Group C: 184 (26.3%) patients (NLR = 2.79-4.31) and Group D: 155 (22.2%) patients (NLR ≥ 4.32). The median follow-up for this cohort was 36 months. The predicted DFI was 132.2, 113.1, 84.4 and 47.9 months and the OS was 141.1, 117.6, 88.7 and 51.2 months for Groups A, B, C and D, respectively. As the NLR increases, there is a reduction in long-term survival. CONCLUSION: The pre-operative NLR is cost effective and has equivalent prognostic value to pre-operative tumour markers for patients with PMP treated with CRS and HIPEC. The NLR is a reliable tool that may have a role in predicting outcomes following CRS and HIPEC for patients with PMP of appendiceal origin.

Short-term outcomes following cytoreductive surgery and heated intra-peritoneal chemotherapy at Waikato.

AIM: Pseudomyxoma peritonei is a rare disease that affects 1-2 per million population per year. Treatment with cytoreductive surgery with heated intraperitoneal chemotherapy (CRS with IPC) has been well described. The purpose of this study was to look at the short-term outcomes following CRS with IPC for all such patients treated in Waikato. METHOD: Records for all patients presenting to surgery for CRS with IPC were retrospectively reviewed. CRS with IPC was performed in accordance with the techniques described by Sugarbaker. Data recorded included patient characteristics, characteristics of surgical treatment and early post-operative outcomes. RESULTS: Sixty-eight patients underwent 72 procedures. Fourteen patients were deemed unresectable at surgery and were treated palliatively. The median age was 57 with the majority being female (59%). The median time, from the decision made for surgery to CRS with IPC, was three months. The median prior surgical score was 1 and the median peritoneal cancer index (PCI) was 19.5. The median operating time was 9.08 hours (5.43-15.20). The majority of patients (76%) had pseudomyxoma peritonei, while the remainder had a combination of other appendiceal, colorectal, ovarian, gastric and primary mesothelial primaries. The major complication rate was 24% and the 30-day mortality rate was 1.4%. The median hospital stay was 12 days. CONCLUSION: Short-term outcomes following CRS with IPC at Waikato are comparable to those published in the literature. Further follow-up is anticipated for the publication of survival and recurrence data.