Neuroblastoma-like schwannoma with giant rosette: A potential diagnostic pitfall for hyalinizing spindle cell tumor.

Neuroblastoma-like schwannoma (NLS) is a rare variant of a common tumor. The aim of this study is to discuss, through a literature review, the differential diagnoses of NLS while emphasizing the importance of ancillary studies. So far, 24 cases have been reported. We describe an additional case in a 64-year-old woman who had a 3-cm subcutaneous tumor on her flank. The histological examination showed an encapsulated neoplasm. Most of the tumor was made of giant rosettes. These rosettes had several sizes reaching 2.6 mm. They showed a palisade of rounded cells. Nuclei were hyperchromatic but bland. The center was made of eosinophilic cores of collagenous radiating fibrils. Neoplastic cells stained strongly for S-100 protein. In the capsule, perineural cells stained for epithelial membrane antigen (EMA). No expression of Mucin 4 (MUC4) was present. This was consistent with NLS. The same peculiar appearance of giant rosettes has been described in hyalinizing spindle cell tumor with giant rosettes (HSCT). We propose the term "neuroblastoma-like schwannoma" when there are small rosettes, "HSCT-like schwannoma" for tumors with giant rosettes and "collagen-rich schwannoma" when there are "ill-defined" structures reminiscent of rosettes. Immunohistochemical panel containing S100, EMA, and MUC4, as well as molecular testing when needed should be performed.

Primary hepatic lymphoma of mucosa-associated lymphoid tissue type: a case report with cytogenetic study.

Primary hepatic lymphoma of mucosa-associated lymphoid tissue type is extremely rare. Only 38 cases have been reported to date. A case of a 59-year-old man with Helicobacter pylori-resistant gastric ulcers and Buerger disease who was followed up since 1999 is reported. A 2-cm hepatic nodule was incidentally found during partial gastrectomy and corresponded to mucosa-associated lymphoid tissue-type lymphoma without underlying liver disease. Molecular studies showed a clonal immunoglobulin heavy-chain gene rearrangement. Investigations for the mucosa-associated lymphoid tissue lymphoma-associated translocations t(11;18) and t(14;18), as well as the t(3;14)(q27;q32), were negative, whereas trisomy 3 and trisomy 18 were detected.

[Pseudo-angiomatous hyperplasia of mammary stroma: a case with gigantomastia]. / L'hyperplasie pseudo-angiomateuse du stroma mammaire. A propos d'un cas compliqué de gigantomastie.

Pseudo-angiomatous hyperplasia of mammary stroma (PASH) is a histopathological entity which is a microscopic fortuitous finding in mammary biopsies performed for different reasons. It may be symptomatic and appears then as a palpable lump. The term pseudo-angiomatous emphasizes the characteristic aspect of the stroma simulating a vascular tumor. We report a case of PASH in a 71 year-old woman who presented a recurring breast mass with rapid swelling of the mammary gland (70 x 60 x 20 cm) treated by mastectomy. PASH must be distinguished from a well-differentiated angiosarcoma. It is ruled out by immunohistochemistry.

[Multicentric extrahepatic bile ducts carcinoma. Clinical presentation, pathologic features and management]. / Carcinome excréto-biliaire multifocal: aspects anatomocliniques et prise en charge thérapeutique.

Extrahepatic bile ducts carcinoma (EHBC) arises usually in the upper third of the biliary tract. They are rarely multicentric associated or not to a gallbladder carcinoma. We report the case of a 53 years man operated for a head pancreas. Laparatomy revealed a tumour of the middle common bile duct extending to the cystic duct. Histologically it was a multicentric carcinoma of variable types occurring in several sites of the biliary tract. Patient had undergone a simple resection without any complications 9 months later. Although EHBC are morphologically similar to those of the gallbladder, their risk factors, epidemiology and treatment are different. Prognosis depends on proximal involvement of perihilar bile ducts which makes the treatment only palliative.

Sacrococcygeal yolk sac tumor: an uncommon site.

A 30-month-old male infant presented with sacrococcygeal and pre-sacral mass. Ultrasound (US) abdomen revealed a huge pre-sacral mass with irregular margins extending into the pelvis, pushing the rectum antero-laterally. CT scan and MRI confirmed the US findings. Serum alpha fetoprotein level was abnormally elevated. Histopathological examination of surgical-specimen suggested sacrococcygeal yolk sac tumor (YST).