Liver cystic echinococcosis and human host immune and autoimmune follow-up: A review.

Cystic echinococcosis (CE) is an infectious disease caused by the larvae of parasite Echinococcus granulosus (E. granulosus). To successfully establish an infection, parasite release some substances and molecules that can modulate host immune functions, stimulating a strong anti-inflammatory reaction to carry favor to host and to reserve self-survival in the host. The literature was reviewed using MEDLINE, and an open access search for immunology of hydatidosis was performed. Accumulating data from animal experiments and human studies provided us with exciting insights into the mechanisms involved that affect all parts of immunity. In this review we used the existing scientific data and discuss how these findings assisted with a better understanding of the immunology of E. granulosus infection in man. The aim of this study is to point the several facts that challenge immune and autoimmune responses to protect E. granulosus from elimination and to minimize host severe pathology. Understanding the immune mechanisms of E. granulosus infection in an intermediate human host will provide, we believe, a more useful treatment with immunomodulating molecules and possibly better protection from parasitic infections. Besides that, the diagnosis of CE has improved due to the application of a new molecular tool for parasite identification by using of new recombinant antigens and immunogenic peptides. More studies for the better understanding of the mechanisms of parasite immune evasion is necessary. It will enable a novel approach in protection, detection and improving of the host inflammatory responses. In contrast, according to the "hygiene hypothesis", clinical applications that decrease the incidence of infection in developed countries and recently in developing countries are at the origin of the increasing incidence of both allergic and autoimmune diseases. Thus, an understanding of the immune mechanisms of E. granulosus infection is extremely important.

Two synchronous somatostatinomas of the duodenum and pancreatic head in one patient.

Somatostatinomas are extremely rare neuroendocrine tumors of the gastrointestinal tract, first described in the pancreas in 1977 and in the duodenum in 1979. They may be functional and cause somatostatinoma or inhibitory syndrome, but more frequently are non-functioning pancreatic endocrine tumors that produce somatostatin alone. They are usually single, malignant, large lesions, frequently associated with metastases, and generally with poor prognosis. We present the unique case of a 57-year-old woman with two synchronous non-functioning somatostatinomas, one solid duodenal lesion and one cystic lesion within the head of the pancreas, that were successfully resected with a pylorus-preserving Whipple's procedure. No secondaries were found in the liver, or in any of the removed regional lymph nodes. The patient had an uneventful recovery, and remains well and symptom-free at 18 mo postoperatively. This is an extremely rare case of a patient with two synchronous somatostatinomas of the duodenum and the pancreas. The condition is discussed with reference to the literature.

Perigastric extraskeletal Ewing's sarcoma: a case report.

Ewing's sarcoma (ES) is a neoplasm of undifferentiated small round cells, which occurs in the bones and deep soft tissues of children and adolescents. We present a rare case of a 44-year-old woman with gastric ES presenting with epigastric pain and weight loss. Ultrasound and computed tomography scans indicated a solid/cystic mass in the pancreatic tail. At laparotomy, the tumor was found attached to the posterior surface of the stomach, completely free from the pancreas, with no lymphadenopathy or local metastases. The polynodal, partly pseudocystic, dark-red soft tumor was excised. Histopathology revealed an anaplastic small-round-cell tumor with strong membranous CD99 immunoexpression. Additionally, there was patchy immunostaining for S-100 protein, vimentin, protein gene product (PGP) 9.5 and neuron-specific enolase, and weak focal CD117 cytoplasmic immunoreactivity. The patient had no adjuvant chemotherapy; her postoperative recovery was uneventful, and she remains symptom-free, and without any sign of recurrence at 20 mo. To the best of our knowledge, this is only the third ever case of gastric ES.

Cystic lymphangioma of the pancreas.

Lymphangioma of the pancreas is an extremely rare benign tumour of lymphatic origin, with fewer than 60 published cases. Histologically, it is polycystic, with the cysts separated by thin septa and lined with endothelial cells. Though congenital, it can affect all age groups, and occurs more frequently in females. Patients usually present with epigastric pain and an associated palpable mass. Complete excision is curative, even though, depending on the tumour location, surgery may be simple or involve extensive pancreatic resection and anastomoses. The authors present a 49-year-old woman in whom a polycystic septated mass, 35 mm multiply 35 mm in size, was discovered by ultrasonography (US) in the body of the pancreas during investigations for epigastric pain and nausea. At surgery, a well circumscribed polycystic tumor was completely excised, with preservation of the pancreatic duct. The postoperative recovery was uneventful. Histology confirmed a microcystic lymphangioma of the pancreas. Immunohistochemistry showed cystic endothelial cells reactivity to factor VIII-RA (++), CD31 (+++) and CD34 (-). Postoperatively, abdominal pain disappeared and the patient remained symptom free for 12 mo until now. Although extremely rare, lymphangioma of the pancreas should be taken into consideration as a differential diagnosis of a pancreatic cystic lesion, especially in women.

Portal cavernoma caused by a calcified hydatid cyst of the liver (case report).

A portal cavernoma is a network of porto-porto collateral dilated tortuous veins lying within the hepatoduodenal ligament, which develops as a sequel to portal vein obstruction. This can be the result of extra-hepatic portal vein obstruction from local extrinsic occlusion, or by a prothrombotic disorder, or both. A 56-year-old woman presented with right upper quadrant abdominal pain. Examination and investigations revealed the presence of gallstones, a cavernous portal vein, several calcified hydatid cysts within the liver, grade III haemorrhoids, but no oesophageal varicosities. She had no previous abdominal surgery, and had normal full laboratory workup, including inflammatory markers, clotting analyses, and thrombophilia screen. At open surgery it became apparent that the portal cavernoma had been caused by local pressure from a calcified hydatid cyst of the caudate lobe of the liver. To the best of our knowledge, this is the first report of portal cavernoma caused by a hydatid cyst of the liver.

Metastatic melanoma to the common bile duct causing obstructive jaundice: a case report.

Metastatic melanoma to the common bile duct is very rare with only 18 cases reported so far. We report a 46 year old women who, 18 mo after excision of a skin melanoma, developed a painless progressive obstructive jaundice. At operation a melanoma within the distal third of the common bile duct was found. There were no other secondaries within the abdomen. The common bile duct, including the tumor, was resected and anastomosed with Roux-en-Y jejunal limb. The patient survived 31 mo without any sign of local recurrence and was submitted to three other operations for axillar and brain secondaries, from which she finally died. Radical resection of metastatic melanoma to the common bile duct may result in lifelong relief of obstructive jaundice. It is safe and relatively easy to perform. In other cases, a less aggressive approach, stenting or bypass procedures, should be adopted.