Multiple Peritoneal Nodules Research Articles

Pancreatic Metastasis from Carcinoid Midgut Tumor. A Case Report

Context Metastatic lesions to the pancreas are rare. We present a case of an ileal carcinoid tumor with a synchronous pancreatic metastasis. Case report A 68-year-old male patient was admitted to our clinic in 2008 for diarrhea and flushing. Urinary serotonin (2x upper reference limit), 5HIAA (5x upper reference limit) and chromogranin A (2.5x upper reference limit) were increased. An octreoscan scintigraphy showed a focal uptake in the pancreatic head and a slight uptake in the lower abdomen. An abdominal CT scan did not show any pancreatic lesions, but a slightly enlarged pancreatic duct in the body of the pancreas. We reviewed the CT scan imaging and we found a hypervascular ileal lesion, confirmed by small bowel barium study. The pancreatic lesion was confirmed by MRI and resulted slightly hypermetabolic with 18 FDG-PET (SUV of 2.15). In November 2008 the patient underwent a duodenum-preserving pancreatic head resection (DPPHR), a cholecystectomy, an ileal resection (about 80 cm) and ablation of small multiple peritoneal nodules. Histology showed multiple well differentiated (Ki67 <2%) ileal carcinoid tumors with lymph-node metastases and tiny peritoneal secondary lesions. The pancreatic lesion resulted to be a metastasis of the carcinoid with positive serotonin staining. The patient is still alive with diarrhea, biochemical evidence of disease and multiple pulmonary metastases 48 months after surgery. Conclusion Pancreas is an uncommon site of metastatic spread in midgut carcinoids and should be considered in case of pancreatic synchronous lesions. In the literature we found a single case report in the last 10 years.

Food residue granuloma mimicking metastatic disease on FDG-PET/CT

A 31-year-old woman presenting with acute abdomen underwent an emergency Hartmann's procedure for fecal peritonitis due to perforated adenocarcinoma of the left colon. Shortly after a 7-month course of adjuvant chemotherapy, follow-up contrast-enhanced CT showed multiple peritoneal and hepatic nodules, showing focal intense and homogeneous FDG uptake on FDG-PET/CT, highly suspected for recurrence of disease. Excisional biopsy of the nodules revealed foreign body granulomas made up of alimentary materials surrounded by a fibrous wall. We report a unique case of a false-positive finding secondary to food residues mimicking metastatic disease on FDG-PET in a patient with colon cancer.

Deciduoid mesothelioma: Cytologic presentation and diagnostic pitfalls

We report two cases of malignant deciduoid mesothelioma (MDM), a very rare variant of malignant mesothelioma (MM). Case 1: An 18-year-old male with no history of asbestos exposure presented with worsening abdominal pain, anorexia, and vomiting after a motor vehicle accident. A CT scan showed small amount of ascites and abdominal mass. An exploratory laparotomy revealed multiple yellow tan, firm nodules on the peritoneum and omentum. He received palliative treatment and died 5 months after the diagnosis. Case 2: A 64-year-old female with history of asbestos exposure initially presented with abdominal distension. CT scan showed abdominal mass with a large amount of ascites. A diagnostic laparoscopy revealed multiple peritoneal nodules. She underwent several regimens of chemotherapy over a period of 69 months and is still alive to date. In both cases, features of mesothelial origin were subtle and the smears showed predominantly single cells with marked nuclear atypia. The second case also contained few two-dimensional loose cell clusters with scalloped or hobnail borders. The clusters often exhibited a pseudoacinar structure surrounding a globular extracellular material. Groups of three to four cells often formed doublets and triplets with cell-to-cell windows. Our results show that MDM may not present with the traditional cytological features described in MM and can manifest with more nuclear pleomorphism resulting in erroneous diagnosis. Recognition of the subtle mesothelial features along with the appropriate ancillary tests is essential for accurate diagnosis.

Tumor desmoplásico de células pequeñas y redondas. Diagnóstico y tratamiento

Desmoplastic small-round-cell tumor is an uncommon highly aggressive type of cancer that affects young men. We present the case of a 31-year-old man with stage iv desmoplastic small-round-cell tumor, diagnosed in the context of abdominal pain and hemoperitoneum. Surgery confirmed extensive hemoperitoneum and revealed multiple peritoneal nodules. Hemostasis was performed, a biopsy was taken, and chemotherapy was initiated. Seven months after surgery, the patient is still alive. Desmoplastic small-round-cell tumor usually occurs in the abdominal or pelvic peritoneum and is associated with nonspecific signs and symptoms but with a unique cytogenetic profile [a translocation t(11;22)(p13;q12) affecting the EWS and WT1 genes]. The best outcomes are produced by a combination of chemotherapy, radiotherapy and surgery. Nevertheless, the prognosis of desmoplastic small-round-cell tumor is poor, with an overall 5-year survival rate of 15%.

Malignant Peritoneal Mesothelioma in a 16-Year-Old Girl: Presentation of a Rare Disease

Malignant peritoneal mesothelioma is extremely rarely seen in young patients.A 16 year-old girl presented with appendicitis-like acute abdominal pain. Intra-operatively, multiple confluent peritoneal nodules were seen on the entire greater omentum and in the pelvis infiltrating the uterus and both ovaries. Biopsies were obtained and interpreted as serous ovarian carcinoma. Radical surgical resection and hyperthermic intraperitoneal chemotherapy -(HIPEC) with carboplatin was performed and followed by 2 cycles of carboplatin/paclitaxel. Histological reevaluation showed characteristic features of epithelioid peritoneal mesothelioma and ruled out serous ovarian cancer. Therapy was continued with 6 cycles of pemetrexed/cisplatin.3 months after end of chemotherapy vital tumor tissue was found in the recess behind the liver, which could be resected completely. The patient is currently disease-free 17 months after initial diagnosis.Malignant peritoneal mesothelioma in young female patients might be under-recognized and possibly misdiagnosed as ovarian serous carcinoma in some cases. International and interdisciplinary cooperation is necessary in order to provide evidence based guidelines for diagnosis and treatment in the future.

A 21-year-old woman with multiple cancers and a new brain lesion

A 21-year-old right-handed woman, who was the product of a normal birth to nonconsanguineous parents and had normal early infantile development, was diagnosed with Burkitt lymphoma of the jaw, pelvis, and kidney at age 3 years. She was treated with 18 months of systemic cyclophosphamide, vincristine, methotrexate, and prednisolone (COMP) chemotherapy with good response. No recurrence was noted, and she remained active and well throughout her childhood and teenage years. At age 17 years, she was diagnosed with neurofibromatosis type 1 (NF1) when she presented with multiple subcutaneous tender nodules bilaterally over her shins, which had developed over months. She was found to have numerous cafe-au-lait skin lesions, axillary freckling, and Lisch nodules. Six months later, she presented with abdominal pain, cramping, hematochezia, and vomiting. Abdominal imaging revealed bowel obstruction and a mass in the descending colon. Colonic resection was performed, and pathology confirmed invasive grade 2 colonic adenocarcinoma, with one positive lymph node, in addition to an abnormal number of tubuloadenomas with low-grade dysplasia (T3N1M0). Tumor analysis suggested normal human MutS homolog (hMSH) protein expression, but an absence of human MutL homolog 1 (hMLH1) DNA mismatch repair expression. She completed a standard regimen of postoperative adjuvant 5-fluorouracil (5-FU) and leucovorin. One year after her initial colon cancer diagnosis, she presented with recurrent abdominal pain and multiple pelvic and peritoneal nodules. Peritoneal biopsy and left salpingo-oophorectomy confirmed recurrent metastatic colonic adenocarcinoma. At the patient's request, chemotherapy was deferred; however, due to continued pain and progressive disease, chemotherapy was initiated with irinotecan, 5-FU, and leucovorin. Her chemotherapy was again changed to oxaliplatin, 5-FU, and leucovorin (FOLFOX) because of continued disease. Despite an initial favorable response, she developed continued peritoneal nodules, a periaortic mass, and increased small bowel disease, leading to resection of portions of the ilium and jejunum, and, ultimately, a …

Peritoneal Mullerian Tumor-Like (Endosalpingiosis-Leiomyomatosis Peritoneal): A Hardly Known Entity

We describe a case of multiple peritoneal nodules with cysts at the free border of the omento and other locations of the peritoneal surfaces. A total abdominal hysterectomy and bilateral salpingooophorectomy were performed for a myomatous uterus and bilateral ovarian cysts. The omentum and several fragments of the abdominal peritoneum were also removed. Microscopic diagnosis was Disseminated Peritoneal Endosalpingiosis-Leiomyomatosis.

Response to imatinib rechallenge in a patient with a recurrent gastrointestinal stromal tumor after adjuvant therapy: a case report

IntroductionAdjuvant imatinib improves recurrence-free survival of patients following resection of primary KIT-positive gastrointestinal stromal tumors. However, it is unknown whether patients who previously received adjuvant imatinib therapy will respond to imatinib rechallenge as treatment for recurrent disease. Here we present the first report documenting the benefits of imatinib rechallenge in a patient previously exposed to imatinib during adjuvant treatment.Case presentationA 51-year-old Asian woman with a wedge-resected primary gastric gastrointestinal stromal tumor at high risk of relapse underwent two years of adjuvant treatment with imatinib. Only 10 months after the completion of adjuvant imatinib treatment, a computed tomography scan revealed gastrointestinal stromal tumor recurrence in this patient, with multiple peritoneal nodules in the upper abdomen being detected. Our patient was rechallenged with imatinib 400 mg/day and had a partial response after one month of treatment. Imatinib rechallenge was well tolerated by our patient; the only adverse events she experienced were grade 1 edema, anemia and fatigue. Our patient maintained a partial response two years and six months after the imatinib rechallenge. However, computed tomography scans three months later showed that our patient had disease progression.ConclusionsThis case report demonstrates that a patient with a gastrointestinal stromal tumor who had previously received adjuvant imatinib therapy responded to imatinib rechallenge as treatment for her recurrent disease. These results indicate that imatinib sensitivity can be maintained in a patient with previous exposure to adjuvant imatinib therapy.

Peritoneal Bile Granulomas Identified at Cesarean Section and Mimicking Disseminated Malignancy

A 37-year-old woman was found to have multiple peritoneal nodules, including on the uterine serosa, at Cesarean section. Histology showed yellow crystalline material surrounded by histiocytes and occasional multinucleate giant cells. Further enquiry revealed that the patient underwent a cholecystectomy for a perforated gallbladder 3 years earlier. Pathologists should be aware of this uncommon complication of bile leakage, which has the potential to clinically mimic disseminated malignancy. This may become increasingly common in the future since bile leakage is more likely to occur with laparoscopic than open cholecystectomy.

Sclerosing encapsulating peritonitis (abdominal cocoon) associated with liver cirrhosis and diffuse large B‐cell lymphoma: Autopsy case

A case of sclerosing encapsulating peritonitis (SEP) associated with liver cirrhosis (LC) and complicated by diffuse large B-cell lymphoma (DLBCL) is reported herein. A 49-year-old Japanese man had undergone peritoneo-venous shunt against refractory ascites due to hepatitis C virus-positive uncompensated LC for 2 years. After he received a diagnosis of DLBCL of the left neck lymph node 3 months before his death, palliative care was given because of his poor general condition. He developed severe abdominal distention and pain over 1 week and was found to have marked ascites and whole bowel lumped together on abdominal CT. At autopsy, the peritoneum was covered with a thick white membrane and the bowel could not be distinguished, which was macroscopically characterized by a cocoon-like appearance. Histology indicated a proliferation of diffusely thickened or hyalinized fibrocollagenous tissue in the entire peritoneum with a slight chronic inflammatory infiltrate and without remarkable change of mucosa. A diagnosis of SEP, also known as abdominal cocoon, was established based on these features. Additionally, in the abdominal cavity, a large amount of serous ascites and multiple peritoneal nodules or masses involved by DLBCL were recognized. To the authors' knowledge this is the first case report of SEP associated with LC and complicated by the invasion of DLBCL in the abdominal cavity.

Endocytoscopy assisted laparoscopic intraoperative diagnosis of disseminated malignancy

An endocytoscope system is a novel accessory tool to the conventional luminal endoscope which provides 450X magnification of the gastrointestinal mucosa, thus allowing in vivo imaging of living cells (Fig. 1) [1]. It has been used with success in the evaluation of esophageal, gastric, and colorectal mucosal lesions during endoscopy [2]. First experience of its use in the intraoperative evaluation of the pancreatic ductal mucosa has also been reported [3]. However, the utility of the system in the in vivo microscopic evaluation of peritoneal lesions has not been reported yet. Two patients underwent diagnostic laparoscopy for evaluation of ascites of unknown origin. The first patient was a 45 year old woman who presented with complaints of painless distension of the abdomen associated with malaise for the past 1 month. Ultrasound of the abdomen showed ascites and thickened omentum. CT scan of the abdomen showed similar findings. The second patient was a 50 year old male patient who presented with progressive distension of the abdomen for past 3 months associated with low grade fever and weight loss. Ultrasound showed free fluid in the abdomen with thickened omentum and minimal bilateral pleural effusion. CT scan was noncontributory. Ascitic fluid examination in both the patients showed exudative ascites with low SAAG (serum ascites albumin gradient) values. Microscopic examination showed a lymphocytic picture and no atypical cells were identified. As all the above investigations were nondiagnostic, both patients underwent diagnostic laparoscopy. Both the patients were found to have moderate amount of straw colored ascites and multiple peritoneal nodules (Fig. 2A). The peritoneal nodules were biopsied and sent for histopathological examinations. Methylene blue solution, in half strength, of approximately 3–5 ml was sprayed via the laparoscope over the nodules. After the nodules were adequately stained the endocytoscope was passed into the peritoneal cavity via a 5 mm laparoscopic port (Fig. 2B). When the scope was applied in contact with the stained nodules, the intricate microscopic details of the lesions could be observed live on the video monitor. The video was relayed to the pathology department, and the pathologist helped inecognising the pathognomonic features of malignant lesions. The endocytoscopy picture in the first patient showed irregular clusters of cells with hyperchromatic nucleus and increased nuclear cytoplasmic ratio suggestive of malignancy (Fig. 3A). Similar cells were also found coursing as emboli in the capillaries of the nodules. The picture in the second patient showed cells with normal nuclear cytoplasmic ratio dispersed sparsely over the peritoneal surface, showing no evidence of malignancy (Fig. 3B). Conventional histopathological examination showed poorly differentiated carcinoma in the nodules of the first patient. The second patient was found to have granulomas suggestive of tuberculosis. With increasing experience the surgeons could make the diagnosis with accuracy without the assistance of the pathologist. The cytoscopy added an extra 5–10 minutes to the total procedure. In conclusion, the endocytoscope system when used via the laparoscope can provide on-table diagnosis of presence G. V. Rao M. J. Mansard (&) P. Rebala Department of Surgical Gastroenterology, Asian Institute of Gastroenterology, 6-3-661, Somajiguda, Hyderabad 500082, India e-mail: jeymagnus@gmail.com

A Case of Tuberculous Enteritis Mimicking Crohnʼs Disease

Purpose: A 20-year-old Guatemalan male with no significant past medical history presented with complaints of one week of abdominal pain, nausea and vomiting. Labs were unremarkable. A CT scan of the abdomen and pelvis revealed evidence of a small bowel obstruction. After the patient showed no improvement in symptoms with bowel rest and decompression, a small bowel enteroscopy was performed. The enteroscopy showed a stricture within the proximal jejunum, ulcerations distal to the stricture, and diverticulae proximal to the stricture. Biopsies of the ulcerations revealed noncaseating granulomas. Acid fast bacilli (AFB) and fungal stains were negative. Based on the biopsy, there was a concern for the possibility of Crohn's disease so the patient was started on steroids and antibiotics. When the patient did not improve over the next 48 hours, he was referred for a surgical evaluation. A laparotomy revealed the presence of multiple peritoneal nodules, and lysis of adhesions was performed without bowel resection. Biopsies showed caseating granulomas with positive AFB stains. The patient's PPD, HIV test, and chest X-ray were all negative. The patient was started on rifampin, ethambutol, pyrizinamide, and levofloxacin. He showed an improvement in symptoms within six weeks. This case highlights the need for a high index of suspicion for tuberculous enteritis when evaluating patients with possible Crohn's disease, especially HIV patients and immigrants from areas where TB is endemic. Tuberculous enteritis rarely causes a small bowel obstruction. However, in cases where it causes strictures, obstruction is a common complication. Tuberculous enteritis is the most common extrapulmonary manifestation occurring in 25% of patients with pulmonary TB. Although our patient presented with proximal small bowel involvement, the majority of patients (75%) have distal small bowel and ileocecal involvement. As highlighted in this case, diagnosis is often difficult because common screening methods and microbiological diagnostics often fail to detect gastrointestinal TB. However, a prompt diagnosis can help prevent the development of serious complications such as intestinal fistulas, obstruction, and perforations.Figure: Small Bowel Enteroscopy described above

La léiomyomatose péritonéale disséminée : profil immunohistochimique et origine

Leiomyomatosis peritonealis disseminata (LPD) is a rare disease presenting as multiple peritoneal nodules of smooth muscle cells, mimicking peritoneal carcinomatosis. This disease usually pursues a benign course. We report one case of LPD in a 32-year-old woman, G2P1, without gynecological history. At term, she had an elective caesarean section during which several firm peritoneal nodules, ranging from 0.2 to 0.4 mm, were found. Microscopic examination showed a smooth-muscle cell proliferation with no mitosis, no atypia and no necrosis. Immunohistochemical analysis showed diffuse and strong staining for progesterone receptors and partial expression of estrogen receptors. The cells coexpressed smooth muscle actin, desmin, h-caldesmon, calretinin, WT1, and CD117 (KIT). They were weakly positive for EMA but negative for CD34. Proliferation index was low with 5% of cells being positive for MIB-1. This case of LPD proved to have an unusual immunohistochemistry profile raising the question of its real origin.

Hepatoid malignancy of unknown origin—a diagnostic conundrum: review of literature and case report of collision with adenocarcinoma

Hepatoid carcinomas are a group of neoplasms with features resembling hepatocellular carcinomas. Although rare, more cases have been noted to arise from various organs within the last decade. Differentiating these tumors is not only a challenge but also critical, since treatment modalities and operative strategies are dependent upon the exact nature of the hepatoid cancer. Based on a review of literature, we discuss the guidelines for differentiating these tumors and utilize these criteria to differentiate these tumors irrespective of their primary tissue of origin. We also describe an unusual case of hepatoid variant of primary peritoneal yolk sac tumor presenting with extensive carcinomatosis and as a collision with two synchronous primary colonic adenocarcinomas, neither of which has been reported to our knowledge to date, thereby falsely mimicking metastatic dedifferentiated colonic adenocarcinoma. A septuagenarian female presented with weight loss, chronic anemia and ascites associated with bloating. Her past history was significant for COPD, hysterectomy and a bilateral oophorectomy 40 years previously. A work up which included computed tomography (CT) and contrast enema revealed significant ascites with multiple peritoneal nodules causing ascending colonic obstruction. Celiotomy revealed the entire peritoneal surface to be studded with nodules, with the largest measuring 6.0 cm. Intraoperative ultrasound, prompted by the frozen section of nodules resembling liver tissue, revealed no intrahepatic nodules. Right colectomy, omentectomy and tumor debulking were performed. The postoperative course was uneventful except for ascitic leak that spontaneously resolved. The peritoneal nodules consisted of malignant cells arranged in cords that resembled liver tissue. In the absence of a primary identifiable liver disease, this is consistent with either hepatoid variant of primary yolk sac tumor or hepatoid carcinoma arising from the peritoneum. The right colectomy specimen revealed two mucosal ulcers consistent with colonic adenocarcinoma abutting two large tumor nodules on the serosal surface. Although grossly appearing to be contiguous, low power examination showed that the serosal nodule and the mucosal lesion were entirely different, and separated by a definite fibrous band. Immunohistochemical stains and patterns were used to differentiate the type of tumor. This article also discusses the criteria used to differentiate hepatoid yolk sac tumors (hepatoid-YSTs), hepatoid carcinomas and metastatic hepatocellular carcinomas and the phenomenon of opisthoplasia observed in certain malignancies. The difficulties encountered in identifying hepatoid carcinomas and current modalities used to differentiate these tumors are highlighted. The phenomenon of opisthoplasia and the challenges posed by this phenomenon in certain metastatic lesions are reviewed and explanations for the possible origins of hepatoid tumors are considered. The most likely explanation in our case is that the hepatoid tumor either originated from microscopic remnant ovarian tissue left behind or primarily from the peritoneum. With no evidence of yolk sac component within the colonic tumor or in the draining lymphatics, this essentially excludes the commonly observed metastatic dedifferentiation (opisthoplasia) of adenocarcinoma to primitive forms (also known as combination tumors). Based on analysis of various factors, including tumor behavior and response to chemotherapy, we conclude that our case was a hepatoid variant of yolk sac tumor presenting in an elderly woman with carcinomatosis. This unusual presentation of two entirely different primary malignancies in close proximity is defined as "collision tumor". This is the first reported case of collision tumors involving dual colonic and primary peritoneal hepatoid-YST. Identifying the exact type still remains to be the most challenging aspect in the diagnosis of hepatoid tumors.

Peritoneal sarcoidosis: Case report and review of the literature

Objectives: This study was performed to report a patient with peritoneal sarcoidosis and review the literature for similar cases. Methods: We described the clinical presentation, course, and outcome of thepatient, and reviewed the medical literature from 1966 till 1997 using MEDLINE and the key words sarcoidosis, scar, and peritoneum. Results: Our patient presented with a rapidly growing tumor-like mass at the site of an old appendectomy scar. Laparoscopy showed a large peritoneal mass and multiple small peritoneal nodules that were found to be noncaseating granulomas by pathology. The MEDLINE search uncovered only 16 cases o peritoneal sarcoidosis, most of which presented with ascites. Conclusion: This case illustrates the need to consider sarcoidosis, in addition to infections and neoplasms, in the differential diagnosis of peritoneal nodules and exudative ascites.

DEEP JUVENILE XANTHOGRANULOMA: An Unusual Presentation

Juvenile xanthogranuloma (JXG) is a disorder of histiocytes usually associated with cutaneous lesions. It may present a diagnostic dilemma in the absence of cutaneous lesions and when deeply located. Differentiation of JXG from other childhood histiocytosis syndromes, especially Langerhans' cell histiocytosis (LCH), is important. We describe an unusual case of deep JXG in a 21-month-old girl with multiple omental and peritoneal nodules presenting with ascites. Although a diagnosis of LCH was suspected clinically, the absence of Birbeck granules and S-100 protein and T6 antigen negativity, together with CD68 and factor XIIIa positivity, led us to a diagnosis of JXG. Physicians should be aware of the widening spectrum of manifestations of juvenile xanthogranuloma.

Unusual Features of Serous Neoplasms of Low Malignant Potential during Pregnancy

Ten serous neoplasms of low malignant potential (LMP) resected during pregnancy were found in the files of the University of Texas M.D. Anderson Cancer Center (UTMDACC). Microscopically, all tumors had marked epithelial proliferation with abundant eosinophilic cells, and eight had intraluminal mucin. Multiple areas of microinvasion were found in eight cases. Additional unusual features were found in three cases. One patient presented with a serous LMP tumor in a supraclavicular lymph node. After resection of an ovarian serous LMP tumor, she was treated with chemotherapy and is without evidence of disease after 21 years. One patient had tumor resected at 24 weeks of gestation and at 2 months postpartum. Marked regression of the epithelial proliferation, the number of eosinophilic cells, and the amount of mucin was seen in the second specimen. Another patient had multiple peritoneal nodules at cesarean section, one of which was biopsied and diagnosed as a primary serous LMP of the peritoneum with multiple areas of microinvasion. Two months later a diagnostic laparoscopy was performed and no residual disease was found. All patients are alive with no evidence of disease. In summary, serous LMP tumors during pregnancy have microscopic and clinical features suggesting aggressive behavior; however, these features appear to regress at the termination of the pregnancy.

Deep Juvenile Xanthogranuloma: An Unusual Presentation

Juvenile xanthogranuloma (JXG) is a disorder of histiocytes usually associated with cutaneous lesions. It may present a diagnostic dilemma in the absence of cutaneous lesions and when deeply located. Differentiation of JXG from other childhood histiocytosis syndromes, especially Langerhans' cell histiocytosis (LCH), is important. We describe an unusual case of deep JXG in a 27-month-old girl with multiple omental and peritoneal nodules presenting with ascites. Although a diagnosis of LCH was suspected clinically, the absence of Birbeck granules and S-100 protein and T6 antigen negativity, together with CD68 and factor XIIIa positivity, led us to a diagnosis of JXG. Physicians should be aware of the widening spectrum of manifestations of juvenile xanthogranuloma.

Intra-Abdominal Desmoplastic Small Round Cell Tumor: Case Report and Brief Review of the Literature

Intra-Abdominal Desmoplastic Small Round Cell Tumor: Case Report and Brief Review of the Literature

Necrotic pseudoxanthomatous nodules of the omentum and peritoneum: A peculiar reaction to endometriotic cyst contents

Necrotic pseudoxanthomatous nodules of the ovary, omentum, and peritoneum are rare, and have been described as a late manifestation of endometriosis. A 39-year-old woman presented with acute abdominal pain and an abdominopelvic mass. Emergency laparotomy revealed a ruptured ovarian neoplasm with several liters of old blood in the abdominal cavity. Left adnexectomy was performed, and exploration of the abdominal cavity revealed no other lesions. Pathologic examination of the neoplasm showed a large endometrioma with an associated endometrioid adenocarcinoma. At surgery 7 weeks later, multiple pseudoxanthomatous peritoneal and omental nodules were found. This case suggests that pseudoxanthomatous nodules of the peritoneum and omentum may arise from a peculiar reaction to endometriotic cyst contents and clinically can mimic metastatic ovarian carcinoma.