Incidental finding of Psuedomyxoma Peritonei in Malignant Peripheral Nerve Sheath Tumour.

Psuedomyxoma peritonei is an infrequent clinical entity characterised by intraperitoneal mucinous/gelatinous ascites produced by the cancerous cells. It has been associated with gastrointestinal, gynaecological, lung and breast tumours. It is commonly asymptomatic and is most often detected incidentally on abdominopelvic imaging or laparoscopy. Higher histological grade of the tumour shows increased metabolic activity on 18F-Fluorodeoxyglucose (FDG) positron-emission tomography (PET) computed tomography (CT). It has been rarely reported in patients with sarcoma. We hereby present an interesting case of incidentally diagnosed pseudomyxoma peritonei on 18FDG PET-CT scan of a patient with soft tissue sarcoma of peripheral nerve sheath.

[A Case of Perforated Low-Grade Appendiceal Mucinous Neoplasm Diagnosed During Appendectomy].

A 46-year-old female presented persistent right lower abdominal pain for 4 days. Computed tomography revealed an enlarged appendix with a surrounding low-attenuation mass. The patient was diagnosed with appendiceal abscess-forming appendicitis and initially treated with antibiotics. However, owing to the manifestation of nausea as a side effect, laparoscopic appendectomy was performed 3 days after the initial consultation. Intraoperative examination revealed mucinous material on the surface of the appendix and within the abdominal cavity, leading to the decision to perform an appendectomy with partial cecum resection and excision of the omentum with mucinous deposits. Pathological examination confirmed the diagnosis of a perforating low-grade appendiceal mucinous neoplasm and pseudomyxoma peritonei. The patient was subsequently referred to a specialized center for ongoing management, and at 9 months postoperatively, surveillance is being conducted. Low-grade appendiceal mucinous neoplasms can progress to pseudomyxoma peritonei through perforation; however, an optimal treatment approach has not yet been established. In particular, patients in advanced stages of the disease often require challenging management decisions. This case is reported along with a review of the literature to provide further guidance.

Serum and ascites tumor markers in the diagnostic and prognostic prediction for appendiceal pseudomyxoma peritonei.

BACKGROUND: To investigate the expression of carcinoembryonic antigen (CEA), cancer antigen 199 (CA199) and CA125 in serum and ascites of appendiceal pseudomyxoma peritonei (PMP) patients relative to their diagnostic and predictive value. METHODS: The study comprised 183 patients with pathologically confirmed appendiceal PMP, enrolled from May 2012 to June 2020, in Aerospace Center Hospital. Serum and ascites tumor markers were obtained, and their diagnostic values were compared by receiver operating characteristic (ROC) curves. The prognostic factors of appendiceal PMP with different pathologic subgroups were calculated by univariate and multivariate Cox proportional hazard regression models. RESULTS: There were significant differences between the numbers of patients with positive CEA and CA199 in serum vs. ascites: p = 0.034 in CEA and p = 0.006 in CA199, respectively. The sensitivities with optimal cut-off values for ascites markers of CEA, CA199 and CA125 were 83.5%, 88.9% and 72.6%, respectively. CEA in ascites showed significant difference in the diagnosis of appendiceal PMP (p = 0.000); the areas under the ROC curves (AUROCs) and specificity were 0.725, 70.7%, respectively. Univariate analysis showed that the higher the ascites tumor markers, the poorer the survival (p = 0.014). Multivariate analysis indicated that completeness of cytoreduction (CCR), ascites CEA and pathological grade were independent risk factors for overall survival (OS). CONCLUSION: CEA in ascites can be used to help specify the origin of PMP. Furthermore, elevation of ascites CEA, high pathological grade and incomplete cytoreduction predicted poor prognosis of appendiceal PMP.

Appendiceal tumors and pseudomyxoma peritonei: current recommendations for clinical practice.

Appendiceal tumors and pseudomyxoma peritonei (PMP) are rare tumors. Perforated epithelial tumors of the appendix are the most common source of PMP. This disease is characterized by the presence of mucin of varying degrees of consistency, partially adherent to the surfaces. Appendiceal mucoceles themselves are also very rare and usually their treatment involves only a simple appendectomy. The aim of this study was to provide an up-to-date review of the recommendations for the diagnosis and treatment of these malignancies according to the current guidelines of The Peritoneal Surface Oncology Group International (PSOGI) and the Blue Book of the Czech Society for Oncology of the Czech Medical Association of J. E. Purkyne (COS CLS JEP).

Prognostic Impact of Pathology, Cytoreduction, and Tumor Markers in Pseudomyxoma Peritonei.

INTRODUCTION: The pathologic classification of pseudomyxoma peritonei is controversial. This study aimed to standardize the histopathological evaluation of pseudomyxoma peritonei and identify the clinicopathological factors associated with survival. METHODS: A pathologic review was performed to systematize the pathology report and verify the relationship between clinical features and survival. Terminology was based on the World Health Organization and Peritoneal Surface Oncology Group International definitions. Preoperative serum levels of carcinoembryonic antigen, CA19-9, and CA-125 were evaluated to determine their association with overall survival (OS) and ability to predict CC0-1 cytoreduction. RESULTS: Among 109 patients with carcinomas resulting from primary appendiceal neoplasms, 72 had pseudomyxoma peritonei of appendiceal origin and underwent debulking surgery. CC0-1 cytoreduction and CC2-3 cytoreduction were achieved in 61% and 39% of patients, respectively. Patients in the CC0-1 and CC2-3 groups had an OS of 122.80 and 32.92 mo, respectively. The histologic grade was associated with CC0-1 cytoreduction; however, it did not influence OS. Patients with CC0-1 cytoreduction, acellular mucin, and low-grade lesions had better disease-free survival. Higher preoperative CA19-9 levels were associated with poor OS. Normal carcinoembryonic antigen values were associated with 100% sensitivity for predicting CC0-1. CA19-9 levels of 625 U/mL were associated with a low possibility of predicting CC0-1. CONCLUSIONS: Histologic grades are associated with disease-free survival when CC0-1 cytoreduction is achieved. Normal preoperative CA19-9 levels were associated with a better OS. CC0-1 cytoreduction is the main determinant of longer survival.

Multiple intestinal hemangioma concurrent with low-grade appendiceal mucinous neoplasm presenting as intussusception-a case report and literature review.

BACKGROUND: Cases with intussusception caused by either intestinal hemangiomas or appendiceal mucinous neoplasms are extremely rare. CASE PRESENTATION: In this study, we reported a 47-year-old male presented with paroxysmal abdominal pain and postprandial bloating for 3 days. CT results indicated a high possibility of secondary intussusception in ascending colon. Histopathology indicated a mixed type of cavernous and capillary hemangioma, combined with low-grade appendiceal mucinous neoplasms (LAMNs) and intestinal obstruction. The patient underwent laparotomy and right hemicolectomy. Finally, the patient was followed up for 4 months with no disease progression. CONCLUSIONS: Rare studies reported the intestine hemangiomas coincided with appendix low-grade mucinous tumor. Its manifestations are not specific, which is a challenge in the preoperative diagnosis. For cases with intussusception that was not observed in time, it may lead to intestinal necrosis and diffuse peritonitis. Additionally, the ruptured mucinous tumor in the appendix may lead to pathogenesis of pseudomyxoma peritonei. Therefore, accurate diagnosis and appropriate surgery-based treatment contribute to the improvement of prognosis and severe outcomes among these patients.

Preoperative plasma D-Dimer level is correlated with peritoneal cancer index of patients with pseudomyxoma peritonei.

PURPOSE: Accurate assessment of preoperative tumor burden contribute to formulate a scientific surgical plan for patients with pseudomyxoma peritonei (PMP). Present study aimed to assess whether the preoperative plasma D-Dimer level could reflect tumor burden for PMP patients. METHODS: A total of 253 PMP patients were included between June 1, 2013 and March 1, 2022. According to the peritoneal cancer index (PCI), all participants were divided into extensive (PCI ≥ 28) and none-extensive (PCI < 28) subgroups. The D-Dimer and tumor markers were compared between the two subgroups. The correlation between the abovementioned biomarkers and PCI will be calculated, and further compared with each other. Two-sided P value less than 0.05 is considered statistically significant. RESULTS: The level of D-Dimer (ng/ml) between extensive and none-extensive subgroup were 600 (328, 1268) vs. 339 (128, 598), Z = -5.425, p < 0.001. The Spearman correlation between D-Dimer, carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA 125), CA 19 - 9 and PCI were 0.487, 0.509, 0.469, and 0.499, respectively (all p < 0.001). The correlation coefficients were compared with each other according to Meng, Rosenthal and Rubin's method, however, there was no significant difference. CONCLUSION: Preoperative plasma D-Dimer could moderately reflect tumor burden for PMP. In the future, a multivariate prediction model will be developed to help surgeons to formulate a more precise surgical plan for the PMP patients.

Incidentally found mucinous epithelial tumors of the appendix with or without pseudomyxoma peritonei: diagnostic and therapeutic algorithms based on current evidence.

Mucinous appendiceal tumors with or without the pseudomyxoma peritonei (PMP) syndrome are rare, but often present as an incidental finding. The confusing histology and lack of large prospective trials result in a considerable diagnostic and therapeutic challenge in these patients. We propose treatment algorithms in patients with incidentally found mucinous epithelial appendiceal tumors, with or without PMP, based on the currently available evidence. The therapeutic approach should take into account the histology and grade of the primary appendix tumor, as well as those of the associated peritoneal disease.

Immunohistochemical staining as supportive diagnostic tool for pseudomyxoma peritonei arising from intraductal papillary mucinous neoplasm: A report of two cases and literature review.

BACKGROUND/OBJECTIVES: Pseudomyxoma peritonei (PMP) arising from an intraductal papillary mucinous neoplasm of the pancreas (IPMN) is a rare condition. The diagnosis of IPMN as the origin of PMP is mainly inferred from the clinical course and the exclusion of PMP from other organs. The pathological diagnosis has not yet been established. To evaluate the usefulness of immunohistochemical staining for the diagnosis of the primary lesion of PMP as IPMN. METHODS: There are 2 cases of PMP arising from IPMN between March 2010 and December 2019 at National Center for Global Health and Medicine. A PubMed search that reported PMP arising from IPMN identified 16 additional cases. Diagnostic methods and clinicopathological features of 18 cases were compared. RESULTS: Four cases including our two cases used immunohistochemical staining for the diagnosis of PMP arising from IPMN. The correspondence of the immunohistochemical staining between PMP and IPMN was shown in the three cases including previously reported two cases and one of our two cases to identify the primary lesion of PMP as IPMN. In addition, we revealed that the comparison of the immunostaining pattern of PMP with the representative immunostaining pattern of the candidate primary lesions is helpful for the diagnosis of the primary lesion of PMP. CONCLUSIONS: Immunohistochemical staining is helpful to identify the primary lesion of PMP as IPMN.

Mode of Presentation in 1070 Patients With Perforated Epithelial Appendiceal Tumors, Predominantly with Pseudomyxoma Peritonei.

BACKGROUND: Perforated epithelial appendiceal tumors are uncommon and can give rise to pseudomyxoma peritonei. Pseudomyxoma peritonei is rare, almost always of appendiceal origin, and presents in various ways relevant to abdominal surgeons. OBJECTIVE: The aim of this study was to report the mode of presentation of pseudomyxoma peritonei of appendiceal origin in patients treated in a high-volume UK peritoneal malignancy center. DESIGN: A retrospective observational study was conducted. SETTINGS: This was a single-center study. PATIENTS: Retrospective analysis of a prospective database of consecutive patients undergoing surgery between March 1994 and December 2016 was performed. MAIN OUTCOME MEASURES: Mode of presentation was classified into 7 categories: "histological diagnosis at abdominal surgery for presumed appendicitis," "probable pseudomyxoma peritonei" based on abnormality on cross-sectional imaging (± image-guided biopsy)," "abnormal imaging (other cause suspected) and operative finding of pseudomyxoma peritonei," "diagnostic laparoscopy," "ovarian mass," "new-onset hernia," and "miscellaneous." RESULTS: Overall, 1070 patients underwent surgery (female 61%, male 39%); median age was 57. The mode of presentation was abnormality on cross-sectional imaging in 324 of 1070 patients (30.3%), histological diagnosis at emergency surgery for presumed appendicitis in 203 of 1070 patients (19%), and abnormal imaging with eventual pseudomyxoma peritonei diagnosis in 180 of 1070 patients (16.8%); 124 of 651 women (19.2%) presented with an ovarian mass. New-onset hernia was the presenting feature in 9.9%; 83 of 1070 patients (7.7%) were diagnosed at diagnostic laparoscopy, and 32 of 1070 patients (3%) were described as "miscellaneous." Overall, 775 of 1070 patients (72.4%) had complete cytoreductive surgery with 10-year survival of 63.5%. LIMITATIONS: Results are limited by the retrospective nature of the study, radiological improvements over the study period, and the number of patients who had overlapping features at presentation. CONCLUSION: Perforated appendiceal tumors present in various ways but predominantly at cross-sectional imaging or coincidentally at laparoscopy or laparotomy. All abdominal surgeons will occasionally encounter cases, often unexpectedly, and recognition and referral to a specialized unit results in excellent outcomes in most cases. See Video Abstract at http://links.lww.com/DCR/B256. MODO DE PRESENTACIÓN EN 1070 PACIENTES CON TUMORES EPITELIALES APENDICULARES PERFORADOS, PREDOMINANTEMENTE CON PSEUDOMIXOMA PERITONEAL: Los tumores epiteliales apendiculares perforados son poco frecuentes y pueden dar lugar a Pseudomyxoma peritonei. El pseudomixoma peritoneal es raro, casi siempre de origen apendicular, y se presenta de diversas formas relevantes para los cirujanos abdominales.El objetivo fue informar el modo de presentación del Pseudomixoma peritoneal de origen apendicular en pacientes tratados en un centro de malignidad peritoneal de alto volumen en el Reino Unido.Se realizó un estudio observacional retrospectivo.Este fue un estudio de centro único.Análisis retrospectivo de una base de datos prospectiva de pacientes consecutivos sometidos a cirugía entre marzo de 1994 y diciembre de 2016.El modo de presentación se clasificó en 7 categorías: "diagnóstico histológico en la cirugía abdominal por presunta apendicitis", "probable Pseudomixoma peritoneal" basado en la anormalidad en la imagen de corte transversal (biopsia guiada por imagen +/-), "imagen anormal (se sospecha otra causa) y hallazgo quirúrgico de Pseudomixoma peritoneal", "laparoscopia diagnostica", "masa ovarica", "hernia de reciente aparicion" y "varios".En total, 1070 pacientes fueron operados (mujeres 61%, hombres 39%); edad media 57. El modo de presentación fue anormalidad en la imágen transversal en 324/1070 (30.3%), el diagnóstico histológico en cirugía de emergencia por presunta apendicitis en 203/1070 (19%), la imágen anormal con eventual diagnóstico de Pseudomixoma peritoneal en 180 / 1070 (16.8%), 124/651 (19.2%) las mujeres presentaron una masa ovárica. La hernia de reciente aparición fue la característica de presentación en 9.9%, 83/1070 (7.7%) fueron diagnosticados por laparoscopia diagnóstica y 32/1070 (3%) "misceláneos". En general, 775/1070 (72,4%) se sometió a cirugía citorreductora completa con una supervivencia a 10 años del 63,5%.Una deficiencia es que los resultados están limitados por la naturaleza retrospectiva del estudio, las mejoras radiológicas a lo largo del período de estudio, y varios pacientes tenían características superpuestas en la presentación.Los tumores apendiculares perforados se presentan de varias maneras, pero predominantemente en imágenes transversales o casualmente en laparoscopia o laparotomía. Todos los cirujanos abdominales encontrarán ocasionalmente con casos, a menudo inesperados, y el reconocimiento y la derivación a una unidad especializada da lugar a excelentes resultados en la mayoría de los casos. Consulte Video Resumen en http://links.lww.com/DCR/B256.).

Macroscopic and microscopic characteristics of low grade appendiceal mucinous neoplasms (LAMN) on appendectomy specimens and correlations with pseudomyxoma peritonei development risk.

Low grade appendiceal mucinous neoplasm (LAMN) is the primary source of pseudomyxoma peritonei (PMP). PMP may develop after seemingly complete resection of primary tumor by appendectomy, which is unpredictable due to lack of reliable prognostic indicators. We retrospectively reviewed 154 surgically resected LAMNs to explore if any of the macroscopic and microscopic characteristics may be associated with increasing risk of PMP development. Our major findings include: (1) As compared to those without PMP, the cases that developed PMP were more frequent to have (a) smaller luminal diameter (<1 cm) and thicker wall, separate mucin aggregations, and microscopic perforation/rupture, all suggestive of luminal mucin leakage; (b) microscopic acellular mucin presenting on serosal surface and not being confined to mucosa; and (c) neoplastic epithelium dissecting outward beyond mucosa, however, with similar frequency of neoplastic cells being present in muscularis propria. (2) Involvement of neoplastic cells or/and acellular mucin at surgical margin did not necessarily lead to tumor recurrence or subsequent PMP, and clear margin did not absolutely prevent PMP development. (3) Coexisting diverticulum, resulted from neoplastic or non-neoplastic mucosa being herniated through muscle-lacking vascular hiatus of appendiceal wall, was seen in a quarter of LAMN cases, regardless of PMP. The diverticular portion of tumor involvement was often the weakest point where rupture occurred. In conclusion, proper evaluation of surgical specimens with search for mucin and neoplastic cells on serosa and for microscopic perforation, which are of prognostic significance, should be emphasized.

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.

A unique presentation of superinfected pseudomyxoma peritonei secondary to a low-grade appendiceal mucinous neoplasm.

BACKGROUND: Pseudomyxoma peritonei (PMP) is an uncommon condition characterized by diffuse mucinous material in the abdomen and pelvis, generally arising from a perforated epithelial neoplasm. Typically, the disease presents as suspected acute appendicitis, ovarian mass, abdominal distension, or ventral hernia. Our case represents a very rare presentation of superinfected PMP. CASE PRESENTATION: A 46-year-old female with a past medical history notable for depression, asthma, and uterine leiomyomas presented to an urgent care with 5 days of progressive abdominal pain, bloating, nausea, and subjective fevers. The patient had a diffusely tender abdomen, without peritonitis, was mildly tachycardic, and had a white blood cell count of 15 K. A CT of the abdomen/pelvis was consistent with PMP with a ruptured appendiceal mucocele versus PMP secondary to an adnexal ovarian neoplastic pathology with an infectious component. The patient initially improved on antibiotics but ultimately required two surgeries, the first of which controlled intraabdominal sepsis while the second permitted definitive management of PMP with cytoreductive surgery (CRS) and HIPEC. CONCLUSION: Superinfected PMP is a rare entity with very few documented cases. A staged approach that incorporates clearing the peritoneal infection, with or without resection of the primary tumor, followed by rehabilitation and definitive surgery appears to be a safe and effective management strategy.

Pseudomyxoma peritonei induced by low-grade appendiceal mucinous neoplasm accompanied by rectal cancer: a case report and literature review.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a disease involving the peritoneum characterized by the production of large quantities of mucinous ascites. PMP has a low incidence, is difficult to diagnose, and has a guarded prognosis. PMP induced by low-grade appendiceal mucinous neoplasm is extremely rare, and PMP accompanied by rectal cancer is even rarer. CASE PRESENTATION: We present a unique case of a 70-year-old male with PMP induced by low-grade appendiceal mucinous neoplasm accompanied by rectal cancer. The patient's clinical, surgical, and histologic data were reviewed. The patient had persistent distended abdominal pain without radiating lower back pain, abdominal distension for 1 month, and no exhaustion or defecation for 4 days. A transabdominal ultrasound-guided biopsy was performed on the first day. The patient received an emergency exploratory laparotomy because of increased abdominal pressure. We performed cytoreductive surgery, enterolysis, intestinal decompression, special tumour treatment and radical resection of rectal carcinoma. The postoperative course was uneventful. The postoperative histological diagnoses were PMP, low-grade appendiceal mucinous neoplasm and rectal medium differentiated adenocarcinoma. At the 1-year follow-up visit, no tumour recurrence was observed by computed tomography (CT). We also performed a literature review. CONCLUSIONS: We should be aware that PMP can rarely be accompanied by rectal cancer, which represents an easily missed diagnosis and increases the difficulty of diagnosis and treatment. Additionally, there are some typical characteristics of PMP with respect to diagnosis and treatment.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei of appendicular and extra-appendicular origin.

BACKGROUND: The prognostic value of the primary neoplasm responsible for pseudomyxoma peritonei (PMP) remains poorly studied. The aim of this study was to determine the prognosis for patients with extra-appendicular PMP (EA-PMP) treated optimally with complete cytoreductive surgery (CCRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: All patients treated for PMP with CCRS and HIPEC between 1994 and 2016 were selected retrospectively from a French multicentre database. Patients with EA-PMP had pathologically confirmed non-neoplastic appendices and were matched in a 1 : 4 ratio with patients treated for appendicular PMP (A-PMP), based on a propensity score. RESULTS: Some 726 patients were identified, of which 61 (EA-PMP group) were matched with 244 patients (A-PMP group). The origins of primary tumours in the EA-PMP group included the ovary (45 patients), colon (4), urachus (4), small bowel (1), pancreas (1) and unknown (6). The median peritoneal carcinomatosis index was comparable in EA-PMP and A-PMP groups (15·5 versus 18 respectively; P = 0·315). In-hospital mortality (3 versus 2·9 per cent; P = 1·000) and major morbidity 26 versus 25·0 per cent; P = 0·869) were also similar between the two groups. Median follow-up was 66·9 months. The 5-year overall survival rate was 87·8 (95 per cent c.i. 83·2 to 92·5) per cent in the A-PMP group and 87 (77 to 96) per cent in the EA-PMP group. The 5-year disease-free survival rate was 66·0 (58·7 to 73·4) per cent and 70 (53 to 83) per cent respectively. CONCLUSION: Overall and disease-free survival following treatment with CCRS and HIPEC is similar in patients with pseudomyxoma peritonei of appendicular or extra-appendicular origin.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei in a liver-transplanted patient: a case report.

BACKGROUND: Diagnostic work-ups in transplanted immunosuppressed patients are a challenge as non-specific findings may be interpreted as transplant-related complications. If the disease in question is rare and slowly developing like pseudomyxoma peritonei (PMP), it is even more difficult. Cytoreductive surgery (CRS) and subsequent hyperthermic intraperitoneal chemotherapy (HIPEC) is the recommended treatment for PMP even with extensive peritoneal spread. CRS-HIPEC for PMP after liver transplantation (LTX) has not been described before. CASE PRESENTATION: A 48-year-old female patient with end-stage primary sclerosing cholangitis (PSC) underwent orthotopic LTX and subsequent pancreaticoduodenectomy after the finding of cholangiocarcinoma in situ in the native common bile duct. Ten years after the transplantation, she developed symptoms and signs suspected to represent graft-related complications. An extensive work-up revealed PMP. Upon reassessment, a cystic mass near the coecum could be seen on computed tomography scan 1 year after transplantation. The multidisiplinary team was hesitant to accept the patient for CRS-HIPEC because of extensive PMP and possible risk to the graft. However, she was eventually accepted and underwent the procedure. The Peritoneal Cancer Index (PCI) was 28 of 39, and surgical debulking was performed followed by HIPEC. The transplant control 2 months after surgery showed no harm to the graft. CONCLUSIONS: Previous LTX should not exclude the possibility for CRS-HIPEC in PMP, even with extensive burden of disease.

[Pseudomyxoma peritonei : a cause of ascites that should not be underestimated]. / Pseudomyxome péritonéal : une cause d'ascite à ne pas négliger.

Pseudomyxoma peritonei (PMP) is a rare condition that refers to a clinical syndrome resulting from the accumulation of mucin in the peritoneal cavity. It results from the intraperitoneal rupture of a mucinous epithelial neoplasm which is classically appendiceal. The prognosis of a limited appendiceal tumor is favourable. Nevertheless, in the case of peritoneal dissemination, the prognosis could be different according to the histological type and therapeutic management. We report the case of a 71-year-old female patient who developed a pseudomyxoma peritonei originating from an appendiceal adenocarcinoma.

Le pseudomyxome péritonéal (PMP) est une condition rare qui se réfère à un syndrome clinique résultant d'une accumulation de mucine dans la cavité péritonéale. Il est secondaire à la rupture intrapéritonéale d'une néoplasie épithéliale mucineuse dont l'origine est classiquement appendiculaire. Le pronostic d'une tumeur appendiculaire limitée est favorable. Toutefois, en cas de dissémination péritonéale, il est variable selon le type histologique et la prise en charge thérapeutique. Nous rapportons le cas d'une patiente de 71 ans ayant développé un pseudomyxome péritonéal secondaire à un adénocarcinome appendiculaire.

Diagnosis of Pseudomyxoma peritonei via endoscopic ultrasound guided fine needle aspiration: a case report and review of literature.

INTRODUCTION: Pseudomyxoma peritonei (PMP) is a rare condition caused by mucinous adenocarcinoma cancerous cells that produce abundance of mucin or gelatinous ascites. This cancer can cause tissue fibrosis and can impair normal organ function. Diagnosis can involve multiple imaging modalities including CT scan. There have been few cases of endoscopic ultrasound (EUS) being used as a means for diagnosis of this condition. Here we report a second case of PMP with a previous history of appendectomy diagnosed with EUS guided fine needle aspiration (FNA) biopsy. CASE STUDY: A 66-year-old male with a history of an appendectomy presented with intermittent abdominal pain for two years and weight loss of 40 pounds over two months. EGD and colonoscopy performed at an outside hospital was unremarkable. CT abdomen revealed perigastric ascities and lesions of the liver. ESR was elevated at 75. At our facility, EUS was performed revealing a peri-gastric and omental mass measuring 36.6 mm × 25.5 mm. FNA performed of both mass and ascetic fluid revealed low grade mucinous adenocarcinoma with mucinous deposits in the peritoneum consistent with PMP. CONCLUSIONS: Endoscopic ultrasound guided FNA, although very rarely used, can be a reliable and safe technique in diagnosis of PMP.

Synchronous Ovarian and Appendiceal Mucinous Neoplasms in the Absence of Pseudomyxoma Peritonei.

BACKGROUND: Synchronous ovarian/appendiceal mucinous neoplasms sometimes occur in the absence of clinical pseudomyxoma peritonei (PMP), which raises a question about whether the 2 tumors could be independent. METHODS: We identified 11 cases of synchronous ovarian/appendiceal mucinous neoplasms without PMP and subclassified them into groups 1 and 2 based on the presence or absence of microscopic peritoneal/ovarian surface mucin deposits. A 7-marker panel (CK7, CK20, CDX2, PAX8, MUC1, MUC2, and MUC5AC) immunohistochemistry was performed on both tumors. RESULTS: Between the 2 groups, there were no significant differences in age, laterality, size, and histology of ovarian/appendiceal tumors. In group 1, 2 of 4 cases developed PMP later, and both had ovarian surface and contralateral ovarian involvement and appendiceal perforation with microscopic mucin deposits on the peritoneum. No patients in group 2 developed PMP. All group 1 cases showed a high degree of concordance of immunoprofile between the synchronous tumors, with an identical expression of appendiceal pattern in greater than 90% of the markers. In group 2, only 1 of 7 cases showed concordance in all markers. CONCLUSIONS: If peritoneal mucin deposits present, even microscopic and acellular, the synchronous tumors are most likely of a single appendiceal origin. Otherwise, they are more heterogeneous, and some may be truly dual primaries.

Pseudomyxoma peritonei: natural history and treatment.

Pseudomyxoma peritonei (PMP) is an uncommon disease characterised by mucinous ascites, classically originating from a ruptured low grade mucinous neoplasm of the appendix. The natural history of PMP revolves around the "redistribution phenomenon", whereby mucinous tumour cells accumulate at specific sites with relative sparing of the motile small bowel and to a lesser extent other parts of the gastrointestinal tract. Peritoneal tumour accumulates due to gravity and at the sites of peritoneal fluid absorption, namely, the greater and lesser omentum and the under-surface of the diaphragm, particularly on the right. The optimal treatment is complete macroscopic tumour excision termed cytoreductive surgery (CRS) combined with Hyperthermic Intra-Peritoneal Chemotherapy (HIPEC). Total operating time for complete CRS and HIPEC for extensive PMP is around 10 h and generally involves bilateral parietal and diaphragmatic peritonectomies, right hemicolectomy, radical greater omentectomy with splenectomy, cholecystectomy and liver capsulectomy, a pelvic peritonectomy with, or without, rectosigmoid resection and bilateral salpingo-oophorectomy with hysterectomy in females. A unique feature of low grade PMP, which differs from other peritoneal malignancies, includes slow disease progression, which may be asymptomatic until advanced stages. Additionally, very extensive disease with a high "PCI" (Peritoneal Carcinomatosis Index) may still be amenable to complete excision and cure. In cases where complete tumour removal is not feasible, maximum tumour debulking can still result in long-term survival in PMP. PMP is challenging, complex but nevertheless the most rewarding peritoneal malignancy amenable to cure by CRS and HIPEC.