Mucinous Carcinoma Peritonei Research Articles

Experimental study on the efficacy and toxicity of intraperitoneal injection of 5-fluorouracil to treat PDX model of pseudomyxoma peritonei

Objective To evaluate the efficacy and toxicity of intraperitoneal injection of 5-fluorouracil (5-Fu) in patient derived xenograft (PDX) model of pseudomyxoma peritonei (PMP). Methods One PMP tumor from surgery was used to establish PMP PDX models, which were equally randomized into control (no treatment), vehicle (normal saline, 0.2 ml) and treatment (5-Fu, 50 mg/kg, 0.2 ml) groups. Experimental peritoneal cancer index (ePCI) score, body weight, and pathological examination were performed to evaluate the efficacy and toxicity. Results PDX models replicating human PMP were established and diagnosed as high grade mucinous carcinoma peritonei with signet ring cells. Average ePCI score of treatment group was significantly lower than control and vehicle groups [(0.9±1.2) points vs. (3.6±1.7) points vs. (2.7±1.1) points, F=9.253, P<0.01]. Histopathological study revealed obvious tumor necrosis and reduced signet ring cells in the treatment group. The Ki-67 label index of treatment group was significantly lower than control group and vehicle group [(57.3±15.1)% vs. (72.2±15.1)% vs. (70.0±14.0)%, F=4.923, P<0.05]. The body weight of treatment group was significantly lower than control group and vehicle group [(19.7±2.8) g vs. (22.7±1.8) g vs. (21.9±1.7) g, F=4.654, P<0.05]. Major toxicities in the treatment group were animal death (10.0%), congestive splenomegaly (88.9%), lymphocyte accumulation (77.8%), bile canaliculus hyperplasia and obstruction (22.2%), cholestasis (100.0%), and acidophilic body (55.6%) in the liver. Conclusion In the PDX model of human PMP, intraperitoneal injection of 5-Fu could inhibit tumor proliferation and progression, with lowered ePCI score and reduced Ki-67, and toxicity was mainly on liver. Key words: Pseudomyxoma peritonei; PDX model; 5-Fluorouracil; Intraperitoneal injection; Organ toxicity

Pathological prognostic factors of pseudomyxoma peritonei

Objective: To analyze the pathological features of pseudomyxoma peritonei (PMP) in correlation with the survival status and independent prognostic factors. Methods: One-hundred and fifty-five PMP specimens were collected at Beijing Shijitan Hospital, Capital Medical University, from 2012 to 2018. Conventional histopathological evaluation was performed to document the primary tumor site, histopathological type, lymph nodes metastasis, tumor emboli in the blood and lymph vessels, nerve invasion and cellular density. The immunohistochemical parameters including Ki-67, p53, MMR-related protein, MUC2 and MUC5AC were analyzed. Clinical follow-up data were reviewed to correlate with pathological prognostic factors using Kaplan-Meier estimator and Cox proportional hazards regression model for univariate and multivariate analysis. Results: Among 155 PMP patients, there were 77 males and 78 females. There were 98 cases (63.2%) of low-grade peritoneal mucinous carcinomatosis, 49 cases (31.6%) of high-grade peritoneal mucinous carcinomatosis, 8 cases (5.2%) of high-grade mucinous carcinoma peritonei with signet ring cells; only 15 cases (9.7%) with lymph node metastasis; 18 cases (11.6%) with tumor emboli in the blood and lymph vessels; 8/126 (6.3%) were positive dMMR; 100 cases (64.5%) had Ki-67 label index <50%, and 56 cases(36.1%) presented with mutant type p53. Univariate analysis revealed 11 survival-related pathological parameters including gender, age, primary tumor site, histopathological type, lymph node metastasis, tumor emboli in the blood and lymph vessels, nerve invasion, cellular density, Ki-67 label index rate, p53 and dMMR. Multivariate analysis identified 4 independent prognostic factors including the histopathological type (HR 59.78, P<0.01), lymph node metastasis (HR 3.74, P=0.028), nerve invasion (HR 7.81, P=0.007) and dMMR (HR 9.82, P<0.01). Conclusions: Histopathological type is the most important prognostic factor of PMP with dMMR as an independent molecular prognostic indicator.

Systemic chemotherapy before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in patients with high-grade mucinous carcinoma peritonei of appendiceal origin

BackgroundThe role of systemic chemotherapy (SC) before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in appendiceal high-grade mucinous carcinoma peritonei (HGMCP) is controversial. We analyzed the effect of SC prior to CRS/HIPEC in HGMCP. MethodsA prospective database of CRS/HIPEC procedures for HGMCP without signet ring cells and with signet ring cells (HGMCP-S) from 1998 to 2017 was reviewed. Exclusion criteria was prior surgery >5 regions or >2 regimens of prior SC. Perioperative variables were analyzed. ResultsThere were 140 HGMCP/HGMCP-S identified: 64 with prior SC (preSC) and 76 without (noSC). Groups were balanced for lymph node status, complete cytoreduction rate, disease burden, complications, and postoperative SC. PreSC had more HGMCP-S, moderately/poorly differentiated histology, and longer time-to-surgery (median: 6 vs 2 months, p < 0.001). Median overall survival (mOS) was 40 vs 86 and median progression-free survival (mPFS) was 19 vs 43 months for preSC vs noSC, respectively (p = 0.006 and p = 0.007). In HGMCP-S subanalysis, mOS was 25 vs 39 and mPFS 16 vs 29 months for preSC vs noSC, respectively (p = 0.188 and p = 0.063). In moderately/poorly differentiated histology subanalysis, mOS was 38 vs 56 and mPFS 18 vs 29 months in preSC vs noSC, respectively (p = 0.199 and 0.082). Prior SC was not linked to improved OS or PFS in non-signet ring HGMCP or well-differentiated histology subanalysis. ConclusionPrior SC was not associated with less disease burden, better cytoreduction rates, or improved clinical outcomes in HGMCP, regardless of histopathologic subtype. Traditional SC agents may not be effective in HGMCP in the neoadjuvant setting.

Pseudomyxoma Peritonei Arising From a Low-Grade Mucinous Neoplasm of the Urachus

Abstract Urachal mucinous tumors range from low-grade lesions traditionally called cystadenomas to frankly invasive mucinous adenocarcinomas. Occasionally, they can lead to the syndrome of pseudomyxoma peritonei (PMP). We report a patient who presented with abdominal distension and had raised tumor markers. A computed tomography scan revealed a calcified cystic lesion of the bladder dome together with features of PMP. These findings were confirmed at laparotomy, and cytoreductive surgery with hyperthermic intraperitoneal chemotherapy was performed. Histologically, the urachal lesion was a low-grade urachal mucinous tumor (mucinous cystic tumor of low malignant potential). The peritoneal disease was associated with ovarian involvement and omental cake and was designated low-grade mucinous carcinoma peritonei on histology. The immunoprofile was typical for lesions of this type, featuring expression of CK20, CEA, and CDX2, but no expression of CK7. We review the literature of PMP arising from urachal primary neoplasms and identify 58 cases reported previously. Based on the limited data available, it appears that urachal lesions account for about 1 in 200 cases of PMP. Owing to the clinical and pathological similarities between urachal and appendiceal mucinous tumors, we recommend a simple classification based on the principles applied to appendiceal lesions and argue this is more appropriate than a classification based on ovarian nomenclature.

Selection and Characteristics of Patients with Peritoneal Dissemination from Appendiceal Cancer with Exceptional/Poor Survival After CRS/HIPEC.

Survival in peritoneal dissemination from appendiceal cancer after complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) varies within each histopathologic subtype. Analyzing patients with unique responses may uncover the mechanisms behind their extreme outcomes. We proposed a method to identify retrospectively and to characterize patients who responded exceptionally well or very poorly within each histopathologic subtype. Retrospective review of patients with low-grade mucinous carcinoma peritonei (LGMCP), high-grade MCP (HGMCP), and HGMCP with signet ring cells (HGMCP-S) with complete CRS/HIPEC (CC-0/1) was performed. Patients were divided by recurrence status. Median follow-up was calculated for each. Exceptional responders (ExR) were defined as alive without recurrence after median follow-up of the nonrecurrent group. Poor responders (PoR) were defined as disease recurrence before median follow-up of the recurrent group. Perioperative characteristics were analyzed. LGMCP, HGMCP, and HGMCP-S had 48 (41%), 19 (23%), and 7 (14%) ExR and 11 (10%), 20 (24%), and 20 (39%) PoR, respectively. All ExR had lower median PCI (26 vs. 36 [p = 0.004]; 13 vs. 33.5 [p < 0.001]; 3 vs. 29.5 [p = 0.001]). Fewer LGMCP and HGMCP ExR had abnormal tumor markers (36% vs. 90% [p = 0.003]; 22% vs. 74% [p = 0.003]). More HGMCP and HGMCP-S ExR had CC-0 (vs. CC-1) cytoreductions (84% vs. 50%, p = 0.041; 100% vs. 40%, p = 0.008). Stratifying patients by recurrence status and follow-up time successfully selects ExR and PoR within each histopathologic subtype. Perioperative characteristics of ExR versus PoR differ across histopathologic subtypes, except for disease burden. Genetic analysis may further elucidate differences and aid in the development of novel targeted therapies.

Outcomes in Peritoneal Dissemination from Signet Ring Cell Carcinoma of the Appendix Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is standard treatment for peritoneal dissemination from appendiceal cancer (AC); however, its role in high-grade histopathologic subtypes (high-grade mucinous carcinoma peritonei [HGMCP] and HGMCP with signet ring cells [HGMCP-S]) is controversial due to their aggressive behavior. This study analyzed clinical outcomes of high-grade AC after CRS/HIPEC. A prospective database of CRS/HIPEC procedures for HGMCP performed from 1998-2017 was reviewed. Perioperative variables and survival were analyzed. Eighty-six HGMCP and 65 HGMCP-S were identified. HGMCP had more positive tumor markers (TM) (CEA/CA-125/CA-19-9) than HGMCP-S (63% vs 40%, p=0.005). HGMCP had higher Peritoneal Cancer Index (32 vs 26, p=0.097) and was less likely to have positive lymph nodes (LN) than HGMCP-S (28% vs 69%, p=<0.001). Complete cytoreduction was achieved in 84% and 83%, respectively. PFS at 3- and 5-years was 59% and 48% for HGMCP vs 31% and 14% for HGMCP-S. Median PFS was 4.3 and 1.6 years, respectively (p<0.001). OS at 3- and 5-years was 84% and 64% in HGMCP vs 38% and 25% in HGMCP-S. Median OS was 7.5 and 2.2 years, respectively (p<0.001). LN negative HGMCP-S had longer median PFS and OS than LN positive HGMCP-S (PFS: 3.4 vs 1.5 years, p=0.03; OS: 5.6 vs 2.1 months, p=0.021). The aggressive histology of HGMCP-S is associated with poor OS, has fewer abnormal TM, and is more likely to have positive LN. However, CRS/HIPEC can achieve a 5-year survival of 25%, which may improve to 51% with negative LN.

Can low grade PMP be divided into prognostically distinct subgroups based on histological features? A retrospective study and the importance of using the appropriate classification

IntroductionThe pathological classification of PMP of appendiceal origin has prognostic and treatment implications. Our goals were to• Classify low grade mucinous carcinoma peritonei (LGMCP) into prognostically distinct subgroups based on histological features.• Compare the reproducibility of the WHO and the PSOGI classifications for both PMP and the appendiceal primary tumor. Patients and methodsA retrospective analysis of patients undergoing CRS and HIPEC or debulking surgery was done. All the tumors were re-classified according to the PSOGI classification. LGMCP was further classified into three histological subgroups and the impact on survival was evaluated. ResultsFrom Jun 2011 to June 2016, 101 patients underwent CRS with HIPEC (n = 89) or debulking surgery (n=12). The median PCI was 28 (3–39) and 74.1% patients had CC-0/1 resections. Of the 76.2% patients who had LGMCP, 4 patients (5.1%) were classified as group 1, 54 (70.1%) as group 2 and 19 patients (24.6%) as group 3. At a median follow up of 21 months, the disease free survival was not reached, 30 months and 14 months for groups 1, 2 and 3 respectively (p = 0.09). There was no difference in overall survival. Using the WHO classification, there was a discordance in the grade of the primary tumor and the peritoneal lesions in 19.8% and conflicting terminology was used in 62% of patients. ConclusionsThe subgroups of LGMCP described here are prognostically different though this needs further prospective evaluation in larger series. The PSOGI classification is more uniformly reproducible and should be preferred to the WHO classification.

Preserving fertility in pseudomyxoma peritonei, a novel approach.

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is the gold standard treatment for patients with pseudomyxoma peritonei (PMP) but involves routine bilateral salpingo-oophorectomy. Young women wishing to maintain fertility may be reluctant to pursue this. An alternative strategy in women with low-grade PMP has been explored in the form of laparoscopic evacuation of pelvic and ovarian mucin with resection of the appendiceal tumour. Between January 2012 and January 2015, four young women (aged 28-35 years) with PMP seeking to maintain fertility underwent laparoscopy, appendicectomy and pelvic mucinous evacuation and washout. Data regarding intra-operative and histopathological findings were collected. Endpoints were fertility-related outcomes and oncological follow-up. Infertility was a presenting symptom in three of the four women. All four had significant pelvic mucinous disease on radiological imaging and were offered CRS and HIPEC as definitive treatment, but chose laparoscopy with appendicectomy and copious irrigation and washout of the pelvis with stripping of mucinous disease off the ovarian surfaces. Postoperative histology demonstrated a low-grade appendiceal mucinous neoplasm (LAMN) in all patients with acellular mucin or low-grade mucinous carcinoma peritonei in the peritoneal cavity. All patients successfully conceived subsequently and gave birth to healthy babies. After 12-29 months follow-up, all women are well with no radiological or laparoscopic evidence of disease recurrence. In patients with low-grade PMP, initial therapeutic laparoscopy can restore fertility, whilst providing short- to medium-term disease control. This modality in young women wishing to have children appears to be a feasible alternative to immediate CRS and HIPEC.

Mucinous Neoplasms Of The Appendix And Peritoneum: Virtual Microscopy For Histomorphologic Assessment And Interobserver Diagnostic Reproducibility

Introduction/ Background Among gastrointestinal (GI) tumours, pseudomyxoma peritonei (PMP) from appendiceal origin has unique clinical and morphologic features. Due to the relative paucity of patients and the absence of therapeutic consensus, evaluation and refinement of the morphologic criteria used for assessment of the disease are still difficult. As a result, a uniformly accepted classification is still lacking. In collaboration with NJ Carr, who initiated the conference consensus process, in Basingstoke, and on behalf of the French group RENA-PATH, 11 experienced GI pathologists agreed to participate to a virtual workshop, in order to assess inter-observer variability in PMP diagnosis and staging. Aims The goal of the study was to evaluate, for appendiceal and peritoneal mucinous neoplasms, the degree of concordance in the identification of diagnostic histological criteria by experienced pathologists, and to assess the degree of inter-individual variation in the application of WHO classification (2010) and TNM staging system (7th edition). Methods A single section stained with hematoxylin and eosin from 9 resected cases of mucinous neoplasms was selected by members of RENA-PATH. All digitalized at a maximum resolution (X40) using an HAMMAMATSU scanner system, to ensure that all participants evaluate exactly the same tumour areas; 1 to 16 questions were prepared for each case. On Teleslide web platform, interactive services provided by TRIBVN. All submitted cases were then reviewed by a panel of 11 pathologists with specific expertise and interest in PMP. Data were analyzed using SAS program. Results Whole slide set evaluated by all participants; no abstention or “unknown diagnosis” for any submitted case. Agreement for classification, WHO 2010: Appendiceal mucinous neoplasms: LAMN 83 %; mucinous adenocarcinoma 92%. Peritonei mucinous carcinoma: Low grade 91.7%; high grade 91.7%. Disagreement on the concept of High Grade AMN defined by low power architecture of LAMN + high grade cytology. Agreement for using pTNM classification (82%) in PMP. Pushing Invasion (PI) and dissection by acellular mucin (DAM) in appendix wall are not reproducible criteria and need to be better defined. Criteria need to be redefined to use HAMN according to a majority of participants. The identification of signet ring cells is not reproducible; the lesion needs to be better defined. Invasion of organs and pattern of invasion (broatfront invasion / classic by irregular glands or single cells with desmoplasia) are not reproducible criteria. Improvement in staging assessment is needed Conclusion: Although histopathological features of peritoneal disease are significant prognostic factors requiring pathologists to classify mucinous carcinoma peritonei (pseudomyxoma peritonei), reproducibility in interpretation must be improved. This international collaborative project allows pathologists worldwide to share their expertise and knowledge through a dedicated interactive workshop session. It is expected an improvement in the management of mucinous neoplasms of the appendix and peritoneum.

Cytoreductive Surgery Plus Hyperthermic Intraperitoneal Chemotherapy for Pseudomyxoma Peritonei Arising from Urachus.

Pseudomyxoma peritonei (PMP) is a rare locoregional disease characterized by disseminated intraperitoneal mucinous tumors. However, little is known about PMP from urachal neoplasm as a result of its rarity. A total of 9 patients with PMP of urachal origin were treated by cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in our institution. All specimens of surgeries were submitted for pathologic examination. Representative slides of tumors and normal urachus were submitted for immunohistochemical staining. Four patients were men; the median age was 48years (range 27-65years). Initial radiologic examination of all patients showed a cystic tumor located between posterior aspect of umbilicus and the dome of urinary bladder, with or without leaking mucin. Complete CRS and HIPEC were performed in all patients. Until the latest follow-up, local recurrence occurred in 1 patient. Other 8 patients had a median disease-free survival of 27.5months. Primary urachal tumors of 9 cases were all mucinous adenocarcinoma. Six patients had low-grade mucinous carcinoma peritonei, and 3 patients had high-grade mucinous carcinoma peritonei. Signet ring cells were noted in 4 patients. All tumor specimens of 9 patients were diffuse positive for CK-20, CDX-2, MUC-2, and MUC-5AC, and were variant positive for CK-7. PMP arising from urachus comes from neoplastic cells with development of intestinal-type mucinous neoplasm. It shares a similar pathophysiology as PMP from appendix. CRS including total urethrectomy, partial cystectomy, and peritonectomy plus HIPEC can be considered as a new option of treatment for PMP originating from urachus.

Perioperative Systemic Chemotherapy for Appendiceal Mucinous Carcinoma Peritonei Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

Perioperative Systemic Chemotherapy for Appendiceal Mucinous Carcinoma Peritonei Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

Perioperative systemic chemotherapy for appendiceal mucinous carcinoma peritonei treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

The role of systemic chemotherapy (SC) in conjunction with cytoreductive surgery (CS) with hyperthermic intraperitoneal chemotherapy (HIPEC) in appendiceal mucinous carcinoma peritonei (MCP) is unknown. A retrospective review (1999-2011) of MCP patients who had undergone CS/HIPEC with or without perioperative SC. Twenty-two low-grade MCP patients treated with CS/HIPEC and SC were matched to patients who received CS/HIPEC alone. Median overall survival (OS) was 107 months for patients treated with perioperative SC compared to 72 without (P = 0.46). CS/HIPEC was performed on 109 patients with high-grade MCP: 70 were treated with perioperative SC, while 39 were not. Median OS (22.1 vs. 19.6 months, P = 0.74) and progression-free survival (PFS) (10.9 vs. 7.0 months, P = 0.47) were similar in patients treated with SC compared to CS/HIPEC alone. Progression while on pre-operative SC was seen in eight patients (17%), while four (8%) had a partial response. Treatment with post-operative SC was associated with longer PFS (13.6 months) compared to pre-operative SC (6.8 months, P < 0.01) and CS/HIPEC alone (7.0 months, P = 0.03). Post-operative SC appears to improve PFS in patients with high-grade appendiceal MCP treated with CS/HIPEC. In contrast, there is no evidence to support the routine use of perioperative SC in low-grade disease.

Pseudomyxoma Peritonei: More Questions Than Answers

Pseudomyxoma Peritonei: More Questions Than Answers

Pseudomyxoma peritonei (mucinous carcinoma peritonei) preceded by intraductal papillary neoplasm of the bile duct

Pseudomyxoma peritonei (mucinous carcinoma peritonei) is a rare clinical disease. Although most cases derive from appendiceal mucinous tumors, a few are associated with pancreatic intraductal papillary mucinous neoplasms. Intraductal papillary neoplasms of the bile duct share many similarities with pancreatic intraductal papillary mucinous neoplasms and are thought to be their biliary counterparts. We report a case of low-grade intraductal papillary neoplasm of the bile duct who developed pseudomyxoma peritonei 6 years after surgical treatment of the primary biliary tumor. To the best of our knowledge, this is the first case of pseudomyxoma peritonei associated with intraductal papillary neoplasm of the bile duct. The tumor recurrence in our case may be due to tumor spillage at the time of the first surgery, since there is no recurrent biliary tumor in the preserved liver lobe. Prevention of spillage of epithelial cell-containing mucin during surgical operations is important in treating intraductal papillary neoplasms of the bile duct.

Pleuropulmonary Involvement in Pseudomyxoma Peritonei: Morphologic Assessment and Literature Review

Intrathoracic spread in patients with pseudomyxoma peritonei (PP) is rare. We reviewed 101 patients uniformly treated at our institution for PP of appendiceal origin. In that study, we suggested mucinous carcinoma peritonei (MCP) as the pathologic terminology for all cases of PP. Four patients had pathologically documented pleuropulmonary involvement. We subsequently examined another patient with pleural invasion. Of 5 patients, 3 had low-grade histologic features in the peritoneum; these showed variably proliferative, bland-appearing neoplastic cells arising from low-grade appendiceal mucinous neoplasms. In 2 cases, 1 or more pulmonary parenchymal metastases of low histologic grade developed. The lack of pleural involvement argued against transdiaphragmatic tumor extension. The third patient with low-grade MCP had direct extension through the left diaphragm involving the left pleural and pericardial spaces without pulmonary parenchymal involvement. In the 2 patients with high-grade MCP, right-sided pleural effusions developed. Neither patient had documented injury to the diaphragm. Pleural cytologic examination revealed high-grade adenocarcinoma cells singly, in small clusters, and in large spheres. The smear backgrounds contained wispy mucin. None of the 5 patients developed thoracic lymph nodal metastases. Although rare, mucinous neoplasms from PP may involve the thorax.

Pleuropulmonary Involvement in Pseudomyxoma Peritonei

Intrathoracic spread in patients with pseudomyxoma peritonei (PP) is rare. We reviewed 101 patients uniformly treated at our institution for PP of appendiceal origin. In that study, we suggested mucinous carcinoma peritonei (MCP) as the pathologic terminology for all cases of PP. Four patients had pathologically documented pleuropulmonary involvement. We subsequently examined another patient with pleural invasion. Of 5 patients, 3 had low-grade histologic features in the peritoneum; these showed variably proliferative, bland-appearing neoplastic cells arising from low-grade appendiceal mucinous neoplasms. In 2 cases, 1 or more pulmonary parenchymal metastases of low histologic grade developed. The lack of pleural involvement argued against transdiaphragmatic tumor extension. The third patient with low-grade MCP had direct extension through the left diaphragm involving the left pleural and pericardial spaces without pulmonary parenchymal involvement. In the 2 patients with high-grade MCP, right-sided pleural effusions developed. Neither patient had documented injury to the diaphragm. Pleural cytologic examination revealed high-grade adenocarcinoma cells singly, in small clusters, and in large spheres. The smear backgrounds contained wispy mucin. None of the 5 patients developed thoracic lymph nodal metastases. Although rare, mucinous neoplasms from PP may involve the thorax.