Gastrointestinal stromal tumor of the ampulla of Vater with osteoclastic giant cells, osteoid-like matrix deposition, and aneurysmal bone cyst-like features.

Gastrointestinal stromal tumors are a heterogeneous group with a wide spectrum of histologic features. We describe the first case of 61-year-old woman who presented gastrointestinal stromal tumors of the ampulla of Vater with osteoclast-like giant cells surrounding osteoid-like material and aneurismal bone cyst-like areas. The phenotype was supported by light microscopy and corroborated by immunohistochemistry analysis.

[Mediastinal ganglioneuroma in an adult patient. A case report and literature review].

We describe the case of an adult patient with a mediastinal ganglioneuroma as a finding in the pathological study and compare its biological behavior with literature findings. A histopathological diagnosis of ganglioneuroma is made possible in the presence of adequate characteristic macroscopic and microscopic variables; nevertheless our case differs with some conventional findings, which made diagnosis during surgery cumbersome. We carried out a literature search to look beyond conventional findings that would enable us to understand its impact on the tumor's biological behavior.

[Mammary gland Rosai Dorfman disease. A case report and literature review].

Rosai-Dorfman disease (RDD) is an uncommon idiopathic, benign histiocytic lesion. It generally involves the cervical lymph nodes and, less often the extranodal sites. Involvement of the breast is rare, with about 18 cases reported in the English literature to date.

[Abdominal wall soft tissue perineurioma. Autopsy findings and review of the literature].

The perineuroma is a rare benign tumor, derived from nerve sheath perineurial cells. It was first described in 1978 by Lazarus and Trombetta, who based their diagnosis on the ultrastructural features of perineurioma cells. Subsequently, the immunohistochemical profile of perineurial cells allowed an easier diagnosis of this condition.