Omental Implants Research Articles

One year follow-up of the colon cancer patient cohort treated with a novel miniaturized robotic-assisted surgery device (mRASD).

With the proven benefits of minimally invasive surgery, there is steady growth in robotic surgery use and interest in novel robotic platforms. A miniaturized Robotic-Assisted Surgery Device (mRASD) has been in clinical use under a multi-center, investigational device exemption (IDE) study for right and left colectomy. The goal of this work was to report the short-term and 12-month outcomes specifically for the cohort of colon cancer patients that underwent surgery using the mRASD. From the IDE study that included both benign and malignant diseases, long-term follow-up was only conducted for patients with colon cancer. The main outcome measures were the oncologic quality metrics (Overall Survival, OS and Disease-free Survival, DFS). Secondary outcomes included incidence of intra-operative, device-related, and procedure-related adverse events. Frequency statistics were performed to assess the measures of central tendency and variability in short (within 30days) and long-term (1-year) outcomes. Thirty total patients underwent a colectomy with mRASD; 17 (57%) were diagnosed with a malignancy and included in this analysis. The mean patient age was 59.9 ± 13.2years. There were no intraoperative or device-related adverse events. In 100% of cases (n = 17), the primary dissection was completed and hemostasis maintained using the mRASD, and negative margins were achieved. At 30days postoperatively, the major complication rate was 6%, and there was one unplanned reoperation for anastomotic leak. At one-year follow-up, the OS and DFS rates were 100 and 94%, respectively. In one patient, omental implants were discovered at the time of surgery, and the patient opted to not undergo additional therapy. The first experience with mRASD for colectomy in colon cancer demonstrated technical effectiveness and an acceptable surgical safety profile in line with other minimally invasive procedures. The study continues to monitor disease recurrence and survival outcomes in this cohort.

Diagnosis of Hepatic Alveolar Echinococcosis with Massive Peritoneal Seeding Treated Surgically- A Case Report

The diagnosis of Alveolar Echinococcosis is often a difficult diagnosis due to its low incidence and a long asymptomatic incubation period. We report a case of a 32-year-old man with an uncommon location of Alveolar Echinococcosis. He presented abdominal pain, conjunctival icterus and dark urine. Abdominal ultrasonography, CT scan and MRI demonstrated the presence of a hepatic lesion and a pararectal mass associated with peritoneal and omental implants. The lesions showed perilesional hypermetabolism on 18F-fluorodeoxiglucose (FDG) positron emission tomography magnetic resonance imaging (PET/MRI). Para-rectal biopsy, serological test, and sample taken during exploratory laparoscopy all suggested Echinococcus multilocularis infection that was later confirmed by PCR test. The patient was treated with Albendazole and underwent curative-intent twostep surgery by right-extended hepatectomy, resection of all peritoneal implants and total mesorectal excision. Thirty months after initial surgery, the patient is doing well and is followed up with MRI and 18F-FDG-PET without morphological signs of recurrence. This case illustrates the capacity of alveolar echinococcosis to affect different organs by infiltration or metastatic dissemination and highlights the role of 18F-FDG-PET/MRI in diagnosis and disease monitoring.

Gliomatosis peritonei associated with mature cystic teratoma – A case report

The case report aims to highlight a rare entity called gliomatosis peritonei. We report a case of a 23-year-old female presenting with an ovarian mass along with multiple omental nodules. On histopathological examination, the ovarian mass was diagnosed as mature cystic teratoma and the omental nodules showed features of gliomatosis peritonei. Gliomatosis peritonei is a rare entity characterized by peritoneal or omental implants of mature glial tissue. GFAP (Glial Fibrillary Acidic Protein) was positive in the omental nodules. Gliomatosis peritonei is an exceptional finding and requires long term follow up of the patient.

Function and composition of pancreatic islet cell implants in omentum of type 1 diabetes patients

Intraportal (IP) islet cell transplants can restore metabolic control in type 1 diabetes patients, but limitations raise the need for establishing a functional beta cell mass (FBM) in a confined extrahepatic site. This study reports on function and composition of omental (OM) implants after placement of islet cell grafts with similar beta cell mass as in our IP-protocol (2–5.106 beta cells/kg body weight) on a scaffold. Four of seven C-peptide-negative recipients achieved low beta cell function (hyperglycemic clamp [HGC] 2–8 percent of controls) until laparoscopy, 2–6 months later, for OM-biopsy and concomitant IP-transplant with similar beta cell dose. This IP-transplant increased HGC-values to 15–40 percent. OM-biopsies reflected the composition of initial grafts, exhibiting varying proportions of endocrine-cell-enriched clusters with more beta than alpha cells and leucocyte pole, non-endocrine cytokeratin-positive clusters surrounded by leucocytes, and scaffold remnants with foreign body reaction. OM-implants on a polyglactin-thrombin-fibrinogen-scaffold presented larger endocrine clusters with infiltrating endothelial cells and corresponded to the higher HGC-values. No activation of cellular immunity to GAD/IA2 was measured post-OM-transplant. Establishment of a metabolically adequate FBM in omentum may require a higher beta cell number in grafts but also elimination of their immunogenic non-endocrine components as well as local conditioning that favors endocrine cell engraftment and function.

Free large sized intra-abdominal endometrioma in a postmenopausal woman: a case report

BackgroundEndometriosis is an estrogen-dependent disease defined by the presence of endometrial glands and stroma out of the uterine cavity. Its prevalence is estimated to be 2–10% in reproductive aged women. Endometriosis occurrence is estimated to be 2.55% in postmenopausal patients due to the decreased levels of estrogen. Endometriosis can present in three different forms: superficial peritoneal implants, ovarian endometriomas, and deep infiltrating endometriosis. Ovarian endometriomas are the most common form of endometriosis. Even though endometriomas have been encountered in various localizations, a free abdominal endometrioma was only reported once in a premenopausal patient. Here, we are reporting the first case of a free large endometrioma in a postmenopausal patient.Case presentationA 67-year-old woman presented to the emergency department at our university hospital complaining of constipation and right flank pain. She suffered from uncontrolled primary hypertension and type 2 diabetes mellitus. On presentation, she was afebrile, hypertensive, and tachycardic. An abdominal CT scan revealed a large cystic mass measuring 17 × 26 cm in the anterior-posterior and transverse diameters respectively. The cyst caused bowel obstruction and right sided hydronephrosis. The patient underwent laparotomy and during the surgical exploration a large abdominal cyst adhered to the greater omentum was found. The cyst received plenteous blood supply from the greater omentum. The uterus and both ovaries were completely normal and didn’t have any connection to the cyst. An en-bloc cystectomy was performed successfully. The final histopathology report confirmed an abdominal endometrioma. The patient had an uneventful postoperative recovery.ConclusionsEndometriomas might reach large sizes regardless of their location or the patient’s age. The close relation of free abdominal endometriomas with the greater omentum suggests that these were developed from endometriotic omental implants. Endometrioma is rare in postmenopausal women. However, it should be considered as a possible differential diagnosis at any age.

Robotic-assisted laparoscopic splenectomy for recurrent ovarian cancer

PurposeRecurrent ovarian cancer frequently involves the spleen. Our aims were to describe the technique of robotic-assisted laparoscopic splenectomy and to evaluate outcomes including progression-free and overall survival in patients who...

Persistent omental trophoblastic implantation following salpingostomy, salpingectomy and methotrexate for ectopic pregnancy: A case report

2% of all pregnancies are ectopic. Optimal surgical management is currently salpingectomy over salpingostomy, secondary to the risks of persistent trophoblastic tissue or omental implants (15%). However, rare cases of omental trophoblastic implants following laparoscopic salpingectomy have been noted in the literature. Current practice dictates that serial determinations of human chorionic gonadotropin (beta-hCG) levels after salpingectomy are not required, as it is considered a definitive treatment. However, given that these cases are hard to interpret through ultrasound and are almost always detected via sudden-onset abdominal pain and acute haemoperitoneum (33%), an argument can be made for post-operative beta-hCG assessment.

Cases of Extra- Medullary Myeloma Presenting As Liver Infiltrates: A Single Community Hospital Experience

Introduction:Multiple Myeloma (MM) accounts for 13% of all hematologic malignancies. Plasma cells (PC) proliferation is mainly restricted to the bone marrow (BM) in most of the patients. Extramedullary myeloma (EMM) is defined by the PCs outside the bone marrow. The prevalence of EMM in myeloma patients has been reported at 7 to 15 percent in newly diagnosed patients and from 6 to 20 percent in relapsed setting. Patients with EMM have poor prognosis with a median overall survival of < 6 months. This abstract presents two cases of MM with initial presentation as a liver infiltrate.Cases:Case one: 74-year-old female presented with epigastric pain. Physical exam was unremarkable. Labs showed Hemoglobin (Hb) 8.3 g/dL, Creatinine (Cr) 2.0 mg/Dl and normal liver function test. Ultrasound showed multiple hypoechoic liver nodules. Biopsy of the liver nodule confirmed plasma cells. Her kappa/lambda ratio 3338, Lactate dehydrogenase (LDH) 423 IU/L, beta2 microglobulin was 9 mg/L. Serum and urine immunofixation(IFE) both confirmed a monoclonal kappa light chain clone. Skeletal survey was negative. BM biopsy showed 30 % kappa clonal plasma cells. Fluorescence in situ hybridization was positive for hyperdiploidy of chromosomes 7, 9, 11, 14, and 17 with partial deletion of IgH gene. Treatment with CyBorD (weekly dexamethasone 20 mg, bortezomib 1.3 mg/m2, and cyclophosphamide 300mg/m2) was started. After 6 months therapy, patient achieved partial response. Then her regimen was switched from CyBorD to VRD (Revlimid 10 mg, bortezomib 1.3 mg/m2 and dexamethasone 40 mg) because of severe side effect. She achieved a good partial response.Case two: 57-year-old male presented with right upper quadrant abdominal pain. Physical exam showed diffuse tenderness but no rigidity or guarding. Initial labs showed Hb 8.4g/dL, Cr 1. 7 mg/dL, total bilirubin of 3 mg/ dl, alanine aminotransferase 81 U/ l and aspartate aminotransferase 98 U/ l. CT abdomen pelvis showed metastatic disease to omental implants, splenomegaly and an enlarged liver. Patient underwent surgery in which it was noticed that omentum was adhered to stomach wall whose wedge resection showed plasma cells infiltrate. Liver biopsy also showed diffuse myeloma infiltration. His kappa /lambda ratio 0.0029, LDH 2187 IU/ L, beta 2 microglobulin was 8 mg/L. Serum electrophoresis showed M spike 3. 8 g with IFE confirmed IgG lambda band. Skeletal survey showed several osteolytic lesions in iliac bone. BM biopsy showed hypercellularity with 90 % plasma cells. Patient was started on CyBorD regimen. Repeat labs after first cycle was significant for rising free lambda light chain making us refer the patient to a University Hospital for further treatments. He was recently started on VDT- PACE ( bortezomib, dexamethasone, thalidomide, cisplatin, doxorubicin, cyclophosphamide, and etoposide).Conclusion:EMM with liver metastasis as initial presentation is rare. Since the low incidence of EMM there are no specific treatment guidelines. There are no clear prognostication factors for EMM. Patients are treated in same way as MM. The current initial treatment relies on whether the patient is a transplant candidate or not.Our first patient showed a good response to treatment. However the second patient had primary refractory disease. Given his young age more intensive chemotherapy like VDT-PACE is a good choice If necessary, should be followed by a autologous transplantation or even allogenic transplantation and/ or involving CAR T- cell therapy.A better understanding of how myeloma cells grow and thrive, as well as the biology of extramedullary tumors, is needed in order to develop better strategies for the treatment of EMM in future. DisclosuresNo relevant conflicts of interest to declare.

Nivolumab in Cholangiocarcinoma: A Case Report

Cholangiocarcinoma is a rare neoplasm that is composed of mutated epithelial cells that originate in the bile ducts.. No potentially curative treatment exists except surgery, but most people have advanced stage disease at presentation and are inoperable at the time of diagnosis. For non-resectable cases due to distal metastasis, the 5-year survival rate is 0%. For those with advanced disease and chemotherapy, a gemcitabine-based therapy has shown some efficacy. Nivolumab, a fully human immunoglobulin G4 programmed death—1 (PD-1) immune checkpoint inhibitor antibody, has been demonstrated to restore T-cell immune activity in treating various malignancies. We report a case in which Nivolumab was used for advanced cholangiocarcinoma with clinically significant response. A 82 year old female (ECOG 2) presented with progressive abdominal pain and nausea and vomiting. CT scan of the abdomen revealed a 6 x 4 cm hepatic mass, suspicious for cholangiocarcinoma with peritoneal metastasis. FNA of the liver lesion was performed which returned positive for poorly differentiated adenocarcinoma staining positive with CK7, CK19, and focal staining with CK17 and CK20. Immunohistochemical stains negative for CDx2, GATA3, Glypican 3, TTF1 and CA19-9 more consistent with pancreas and biliary origin. The patient was treated with gemcitabine with capecitabine for 16 cycles. CT scan after completion showed overall increased size of intrahepatic cholangiocarcinoma (9.3 x 3.9 cm from 8 x 3.3 cm), peritoneal carcinomatosis and numerous small omental implants. After discussion with the patient, the plan to start a PD-1 inhibitor was offered. The patient was started on Nivolumab and now after 27 cycles, which was well tolerated, interval CT scans have shown regression in the size of the tumor. CT scan after the 12th cycle showed measurable decrease in hepatic tumor (8.5 x 3.3 cm from previously 9.7 x 4.2 cm) and portacaval lymph node (1.6 cm x 0.7 cm from 1.9 x 1 cm). Repeat CT scan after 24th cycle of Nivolumab, showed further measurable decrease in hepatic tumor(7.3 x 3.2 cm, previously 8.5 x 3.3 cm) and ascites. Cholangiocarcinoma usually yields an extremely poor prognosis and options are currently limited. Nivolumab appears to be efficacious in patients with advanced cholangiocarcinoma with minimal side effects. Further research needs to be performed to fully assess its potential as a therapeutic option.1329_A.tif Figure 1: No Caption available.1329_B.tif Figure 2: No Caption available.

Peritoneal Nodules in a Pediatric Patient with Benign Teratoma. A Case Report and Review of Literature

Mature ovarian teratomas are common in children. These well differentiated tumors are typically confined to the ovary. In rare cases, they can rupture leading to granulomatous peritonitis that mimics carcinomatosis. Ovarian tumors with peritoneal/omental implants suggest malignant pathology with a different prognosis. A 15-year-old girl presented with 5months of abdominal pain, and weight loss. Computed tomography (CT) imaging of the abdomen revealed a large mass filling the abdomen. Slightly elevated lactate dehydrogenase (LDH) and carcinoma antigen 125 (CA125). On laparotomy an ovarian tumor with peritoneal and omental implants was identified. Left salpingo-oophorectomy, omentectomy, and peritoneal washing were performed. Pathology revealed a benign cystic teratoma. Although ovarian teratomas are typically benign, they might mimic carcinomatosis. In patients with unexpected finding of peritoneal implants, histologic diagnosis is recommended before proceeding with a full oncologic ovarian resection.

Pseudomyxoma peritonei due to low-grade appendiceal mucinous neoplasm with symptoms of inguinal hernia and uterine prolapse: a case report and review of the literature

Pseudomyxoma peritonei (PMP) is an unusual condition in which massive amounts of mucinous ascites in conjunction with mucinous peritoneal and omental implants occur. We herein report a case of PMP due to low-grade appendiceal neoplasm (LAMN) and a literature review to clarify the clinical features of PMP. A 68-year-old female suffered from anorexia and abdominal distension and was referred to the emergency department of our hospital. Right-side inguinal hernia and uterine prolapse were revealed by a physical examination. Abdominal computed tomography at admission indicated massive ascites and a ruptured cystic mass in the lower-right abdomen. We diagnosed the patient with a ruptured appendiceal mucinous adenoma and PMP and scheduled a laparotomy. We performed an appendectomy containing the cystic mass, bilateral oophorectomy, and a biopsy for the peritoneum. We irrigated the abdominal cavity using 3000 ml of dextran solution. The macroscopic findings showed a ruptured cystic mass measuring 5 × 4 cm arising from the middle of the appendix. The bilateral ovaries and peritoneum were also covered with yellow mucin. The pathologic findings revealed the presence of low-grade atypical cells inside the capsule. However, no tumor cells were found on the surface of the ovary or peritoneum. A literature review revealed that the prognosis of PMP due to LAMN is relatively good, with a 5-year survival rate of 80%, and hernia is occasionally caused by PMP. According to this literature review, we knew this case might be a typical case. However, PMP is very rare; we need further follow-up data to select an optimal treatment for preventing the relapse of PMP.

Preoperative CT-based nomogram for predicting overall survival in women with non-endometrioid carcinomas of the uterine corpus.

To develop a preoperative CT-based nomogram for predicting overall survival (OS) in patients with non-endometrioid carcinomas of the uterine corpus. Waiving informed consent, the institutional review board approved this HIPAA-compliant, retrospective study of 193 women with histopathologically proven uterine papillary serous carcinomas (UPSC), uterine clear cell carcinomas (UCCC), and uterine carcinosarcomas (UCS) who underwent primary surgical resection between May 1998 and December 2011, and had a preoperative CT ≤ 6 weeks before surgery. All CT scans were reviewed for local or/and regional tumor extent, presence of pelvic or/and para-aortic adenopathy, and presence of distant metastases. Univariate survival analysis was performed using log-rank test and Cox regression. Variables shown significant by the univariate analysis were evaluated with the multivariable Cox regression analysis and the results were used to create a nomogram for predicting OS. The predictive accuracy of the nomogram was assessed with the concordance probability index (c-index) and a 3-year calibration plot. Mean patient age was 67.2 years (range 49.0-85.9); histologies included UPSC (n = 116), UCCC (n = 27), and UCS (n = 50). Median follow-up was 38.1 months (0.9-168.5 months). At multivariate analysis, patient age, ascites, and omental implants on CT were significant adverse predictors of OS and were used to build the nomogram. Concordance index for the nomogram was 0.640 ± 0.028. We developed a nomogram with a good concordance probability at predicting OS based on readily available pretreatment clinical and imaging characteristics. This preoperative nomogram has the potential to improve initial treatment planning and patient counseling.

Omentum Is Better Site Than Kidney Capsule for Growth, Differentiation, and Vascularization of Immature Porcine β-Cell Implants in Immunodeficient Rats

BackgroundRapid revascularization of islet cell implants is important for engraftment and subsequent survival and function. Development of an adequate vascular network is expected to allow adaptive growth of the β-cell mass. The present study compares omentum and kidney capsule as sites for growth and differentiation of immature β-cell grafts.MethodsPerinatal porcine islet cell grafts were implanted in omentum or under kidney capsule of nondiabetic nude rats. Implants were compared over 10 weeks for their respective growth, cellular composition, number and size of β cells, their proliferative activity, and implant blood vessel density.ResultsIn both sites, the β-cell volume increased fourfold between weeks 1 and 10 reflecting a rise in β-cell number. In the omental implants, however, the cellular insulin reserves and the percent of proliferating cells were twofold higher than in kidney implants. In parallel, the blood vessel density in omental implants increased twofold, reaching a density comparable with islets in adult pig pancreas. A positive correlation was found between the percent bromodeoxyuridine-positive β cells and the vessel density.ConclusionsGrowth of the β-cell volume proceeds similarly in the omentum and under the kidney capsule. However, the omentum leads to higher insulin reserves and an increased pool of proliferating cells, which might be related to a more extended vascular network. Our observations support the omentum as an alternative site for immature porcine islet cells, with beneficial effects on proliferation and implant revascularization.

Abstract 1651: Regulation of omental seeding of ovarian cancer cells by SPARC.

Abstract Epithelial Ovarian cancer is the leading cause of death from malignant gynecologic tumors, as most patients have extensive late metastatic disease at the time of diagnosis. Ovarian cancer (OvCa) cells have specific predilection to metastasize to omentum, a condition known as “peritoneal ovarian carcinomatosis, POC” but rarely leave the peritoneal cavity. Despite aggressive surgical debulking and cytoreduction, recurrence of omental implants is high with poor patient survival. We have recently reported that the tumor suppressor role of matricellular glycoprotein SPARC (secreted protein acidic and rich in cysteine) in POC through differential effects on OvCa cells and their interactions with components of the peritoneal microenvironment. Given that SPARC is the first known matricellular protein involved in adipose tissues homeostasis, we sought to elucidate the potential roles of SPARC on the omental adipocyte-OvCa cells cross-talk and its impact on POC, in vivo and in vitro. Using primary omental SP−/− and SP+/+ omental stromal cells, we found that adipocyte-SPARC delayed the adipogenic differentiation of omental stromal cells. SP−/- omental adipocytes expressed significantly higher levels of adipogeneic markers and accumulated significantly less oil droplets than SP+/+. Primary SP−/− adipocytes promoted homing of ID8 murine OvCa cells to the omentum in vivo and their migration and invasion in 3D-cocultures in vitro. Mechanistic studies using human and murine adipocyte-OvCa genetically manipulated for SPARC expression in 3D co-cultures, revealed that the effect of SPARC suppressing adipocyte-OvCa cell cross-talk mediated by the effect suppressing the activation of cEBP-β, NFκB and AP-1 in OvCa cells as well as in adipocytes with subsequent decrease in chemokines/adipokines as well as fatty acid exchange between OvCa cells and adipocytes. Our data indicates the metastasis suppressor effect of SPARC in POC is mediated in part via inhibiting the key transcription factors involved in adipocytes differentiation and OvCa progression identifying SPARC as a potential inhibitor of OvCa cell omental seeding and dormancy. Citation Format: Dylan P. Matthews, Neveen A. Said. Regulation of omental seeding of ovarian cancer cells by SPARC. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1651. doi:10.1158/1538-7445.AM2013-1651

Diagnostic value of FDG-PET/CT for peritoneal carcinomatosis (PC) before hyperthermic intraperitoneal chemotherapy (HIPEC) in ovarian cancer.

e15574 Background: Evaluate FDG-PET/CT utility for the detection of peritoneal carcinomatosis from ovarian cancer treated by chemotherapy by using surgical and histopathological findings as the standard of reference. Methods: 38 patients (46 to 68 years) with recurrent (n=35) or primary (n=3) ovarian cancer were reviewed for the presence of peritoneal lesions on FDG-PET/CT before cytoreductive surgery and HIPEC treatment. 30 had adenocarcinomas (13 papillary serous, 7 moderately differenciated, 6 poorly differentiated, 3 serous and 1 serous cystadenocarcinoma) and 2 endometrioid tumors. 9 had psammomatous calcifications. All were suspected cases of PC. 35 patients had received adjuvant chemotherapy and 3 neoadjuvant chemotherapy (primary cancer). FDG-PET/CT results were reinterpreted by two experienced nuclear medicine physicians who knew that PC was suspected. The FDG uptake was determined as SUVmax in the most active lesion in all abdomino-pelvic quadrants (average SUVmax= 6.1; range 1.1- 25). SUVmax in the liver was also measured (average SUVmax=2.9). All PET/CT exams were realised on the same machine. Results: FDG PET/CT diagnosed 18 in 32 patients with peritoneal metastases. There was no suspicious site of abnormal FGD uptake in the supradiaphragmatic regions. The sensitivity, specificity and accuracy of FDG PET/CT were respectively 59,100, 66%. The positive and negative predictive value of FDG PET/CT were 100 and 31%. 13 false negative PET/CT findings were due to millimetric or infracentimetric perihepatic, mesenteric and omental implants (unseen on PET/CT) and to nodules less than one centimeter with no significant FDG uptake (SUVmax lower than hepatic uptake). The true negative findings were found after chemotherapy. Conclusions: FDG-PET/CT can be considered as a useful tool for the selection of patients for HIPEC treatment in the absence of distant metastasis. It showed excellent results for the positive diagnosis and tumor burden for lesions more than 1 cm (PPV 100%). The sensitivity was low in the presence of millimetric disease with or without prior chemotherapy before HIPEC.

Unusual Presentations of Metastatic Prostate Carcinoma as Detected by anti-3 F-18 FACBC PET/CT

Prostate carcinoma is the second most common cause of cancer-related mortality in males in the United States. The pattern of metastatic disease of prostate cancer is well recognized, frequently involving sclerotic bone lesions and abdominopelvic lymph nodes. Anti-3 F-18 FACBC acid is a synthetic amino acid analog positron emission tomography radiotracer with reported utility in the detection of prostate carcinoma. We present 2 cases of unusual presentations of prostate carcinoma, one with malignant ascites and omental implants and the other with lytic bone lesions detected with anti-3 F-18 FACBC acid.

Pseudomyxoma peritonei (PMP) - a rare entity

Pseudomyxoma peritonei (PMP) is a rare complication of mucinous tumours of appendiceal or ovarian origin that results in peritoneal and omental implants. Clinical morbidity and mortality arise from the fact that copious amounts of extracellular and peritoneal mucin result in distortion and loss of function of visceral organs. Therapeutic paracentesis is not possible because of the nature of the mucin. Currently, new techniques are being used to attempt to debulk the mucin volume; none, however, has lead to superior outcome.

Endometriosis in the African American woman—racially, a different entity?

Endometriosis has been identified in up to 10% of women in some reports; however, few studies have evaluated African American women. The purpose of this study was to localize the implantation sites of endometriosis in urban Detroit female patients. This study was a retrospective chart analysis of patients with laparoscopes for endometriosis at St. John Detroit Riverview Hospital in Detroit, Michigan. All women had concomitant disease involving the uterus and multiple genital structures. In total, 93% had uterine implants, 62% had ovarian implants, 51% had posterior cul-de-sac disease, and 44% had fallopian tube involvement. Forty-five percent had abdominal wall spread, 8% with large bowel implants, and 13% with small bowel involvement. Fifty percent had uterosacral implants, 2% had bladder involvement, 2% had perihepatic involvement, and 4% had omental implants. African American women appear to have a predilection for uterine implants of endometriosis, which may be due to genetic, environmental, or previously presented theories. Further study of urban African American females is necessary to investigate the departure from typical sites of endometriotic implant localization.

Omental infarction caused by laparoscopy-assisted gastrectomy for gastric cancer: CT findings

To investigate the computed tomography (CT) imaging features of omental infarction in patients who underwent laparoscopy-assisted gastrectomy (LAG) for gastric cancer. A retrospective study was performed on 390 patients who underwent LAG for gastric cancer. Two radiologists evaluated the CT images for the presence of omental infarction. The CT pattern was characterized at initial presentation and the evolutional changes were evaluated. The initial CT appearance of omental infarctions were categorized into the following four types: type 1 (ill-defined, heterogeneous, fat density lesion); type 2 (well-defined fat density lesion with rim enhancement); type 3 (well-defined heterogeneous lesion with fat component); and type 4 (well-defined heterogeneous lesion without a fat component). Of the 390 patients involved, nine patients (2.3%; six male and three female with a mean age of 57 years) were diagnosed with omental infarction. Infarctions averaged 4.1 cm (range 2-7.3 cm) in diameter. Among nine patients with omental infarction, two patients had type 1 lesions, two had type 2, two had type 3, and three type 4. All infarctions became smaller and better defined with evolution. In two patients who presented with type 1 lesions on initial CT, each lesion was progressed to type 2 and type 3 on follow-up CT. In two patients with type 3 lesions on initial CT, the lesions changed to type 4 on follow-up CT. An awareness of the various CT features and evolutional changes in omental infarction after LAG for gastric cancer can help ensure the correct diagnosis and to avoid misdiagnosis for omental implants.

Abstract 1714: Chemoresistance in patients with papillary serous carcinoma of the ovary

Abstract The majority of patients with ovarian carcinoma present at an advanced stage, with metastatic disease throughout the peritoneal cavity. Therefore, patients commonly undergo platinum-based chemotherapy. Even though the initial response rates can be high, the majority of patients will have recurrent disease and the 5-year survival rate is only 10-20%. The human lung resistance protein (LRP) is a multidrug resistance protein that has been shown to be overexpressed in models of chemotherapy resistance, but has not been adequately explored in platinum-resistant epithelial ovarian cancer (EOC). The primary aim of this study was to compare LRP expression in the tumor cells from ascitic fluid with tumor cells from omental metastasis in chemotherapy-naïve patients with advanced EOC. The secondary aim was to explore possible mechanisms in which LRP might cause drug resistance. After IRB approval, patient ascites and metastatic implants were collected and evaluated for platinum sensitivity and expression of LRP, phospho-ERK, and AKT using western blots and immunohistochemistry (IHC). Both ascites and omental metastatic implants were treated with 50 uM carboplatin for 48 hours and cell viability was analyzed. LRP, phospho-ERK, and AKT were analyzed using IHC on samples treated with 50 uM carboplatin or phosphate buffered saline. Of 20 patients who had matched ascites and omental metastatic implants adequate for analysis, 4 were platinum resistant, 3 were platinum sensitive, and 13 displayed intermediate platinum sensitivity. Overall, the malignant cells in ascites were more resistant to carboplatin than the metastatic implants (p=0.001) and the malignant cells in ascites showed higher expression of LRP than the omental metastatic implants by IHC and western blotting. IHC and western blotting also demonstrated that the malignant cells in ascites had lower expression of phospho-ERK and higher expression of AKT than the metastatic implants. After treatment with 50 uM carboplatin, the platinum resistant patients had decrease in phospho-ERK and an increase in AKT versus the platinum sensitive patients who had an increase in phopho-ERK and a decrease in AKT and LRP. High expression of LRP in the tumor cells in ascitic fluid may indicate platinum resistance prior to initiation of platinum-based chemotherapy. Also, changes in phospho-ERK and AKT following platinum based therapy may indicate the extent of response of EOC to this therapy. Supported in part by the Kaleidoscope of Hope ovarian cancer foundation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1714. doi:10.1158/1538-7445.AM2011-1714