[Hemoperitoneum secondary to a malignant tumor of the sheath of the peripheral nerve in the liver].

Malignant peripheral nerve sheath tumors are frequently associated with neurofibromatosis type 1. They are usually located in the extremities or in the axial area. Its visceral location is very rare and its hepatic origin is infrequent.

Gonadoblastoma in a patient with 45,X/46XY mosaicism.

45,X/46,XY mosaicism is a sex development disorder with an estimated incidence of less than 1 in 15,000 live births. Various studies have shown there is an increased risk of germ cell tumours forming in Mosaic Turner syndrome. This includes gonadoblastoma, a clinically benign mixed germ-stromal cell tumour.

Initial assessment of "Gissell's stain": A novel histopathological method for the identification of Helicobacter pylori.

Introduction And Objectives: The histopathological identification of Helicobacter pylori using the routine method (haematoxylin-eosin) is not only very difficult but also has low sensitivity. Giemsa staining is often used in addition, but different protocols do not produce homogeneous results. Furthermore, the Gold Standard recommended by the European Helicobacter Pylori Study Group has been applied in very few studies, thus resulting in uncertain outcomes.

[Pancreatic lipomatous hamartoma: A case report and literature review].

Pancreatic hamartomas (PH) are extremely unusual non-neoplastic tumor-like lesions and accounts for <1% of all hamartomas. Moreover, there is a distinct variant of PH denominated Pancreatic lipomatous hamartoma (PLH), that is even rarer, with only 5 cases, including the present case, reported in the literature. PLH lacks well-defined features and clinically can be mistaken with other lipomatous lesions of the pancreas, including lipoma, pancreatic lipomatosis, PEComa, liposarcoma, and malignant tumors with lipomatous components.

[Concurrence of primary extramammary Paget's disease of the vulva and vulval intra-epithelial neoplasia: A case report].

Extramammary Paget's disease and intraepithelial vulvar neoplasia are common lesions in the vulva. However, their simultaneous occurrence is extremely rare. We present the case of a 77year-old woman who presented with a 16month history of pruritus and a rash in the vulvar region with gradually increasing bleeding.

Intestinal obstruction due to small intestinal metastasis from primary Merkel cell carcinoma of the gluteal region.

Merkel cell carcinoma (MCC) is a rare neoplasm of unknown multifactorial origin first described in 1972. It occurs most often in older Caucasian males and is typically associated with sun-exposed areas of skin. However, cases have also been reported in other areas, such as the trunk and the gluteal region.

[Ectopic hepatocellular carcinoma. A case report].

Ectopic liver (EL) is a rare developmental anomaly caused by the migration of hepatic cells to other locations during embryogenesis. Its incidence is thought to be between 0.24 and 0.

[Malignant gastrointestinal neuroectodermal tumor: A report of 2 cases and a review of the literature].

Malignant gastrointestinal neuroectodermal tumour (GNET) is an extremely rare neoplasm first described by Zambrano in 2003 as clear cell sarcoma like tumor of the gastrointestinal tract. In contrast to clear cell sarcoma, it has giant osteoclast cells and shows diffuse and intense positivity for S-100 with no immunohistochemical or ultrastructural melanocyte differentiation. We present the first cases of GNET reported in South America, occurring in Peru.

[Colloid Carcinoma of the pancreas and synchronous gastrointestinal stromal tumour of stomach. A case report and review of the literature].

Colloid carcinoma (CC) is a rare histological type of adenocarcinoma of the pancreatic duct and is characterized by the presence of large lakes of extracellular mucin containing neoplastic cells. Its 5 year prognosis is more favourable than that of ductal, tubular or not otherwise specified (NOS) adenocarcinomas. We present the case of a 74-year-old woman with a thin walled, multicystic lesion in the tail of the pancreas, radiologically suggestive of a serous cystadenoma as opposed to a mucinous neoplasm.

[Adenosquamous carcinoma of the colon: a case report and review of the literature].

Colorectal cancer is the third most frequently diagnosed cancer in both men and women. Adenocarcinoma is the most common pathologic subtype of colon cancer and constitutes 86% of all colon cancers. Nontheless, there are other less frequent sybtyes of colorectal carcinomas, such as adenosquamous carcinoma, an extremely rare form of colon cancer, but with worse prognosis and greater potential of metástasis.

[Mucinous cystic neoplasm of the liver: a case report and review of the literature].

Mucinous cystic neoplasm (MCN) of the liver is an unusual cyst-forming epithelial neoplasm, typically showing no communication with the bile ducts. This neoplasm represents less than 5% of all cystic lesions of the liver and there are only 250 cases in the world literature. We present the case of a 23-year-old female with a 13.

[Appendicular desmoid tumor: unusual case and review of the literature].

Background: Desmoid type fibromatosis is a benign neoplastic process non-encapsulated locally invasive and aggressive, which arises from a proliferation of bland-looking fibroblasts and myofibroblasts. The most frequent location of fibromatosis is extraabdominal (60%), abdominal wall (25%) and intra-abdominal (8-15%), rarely can originate in the viscera (0.73%), such as the pancreas, gastroesophageal junction, diaphragm and appendix.