Schwannomas, also known as neurinomas or neurilemmomas, are generally benign, slow-growing neoplasms originating in any nerve that has a Schwann cell sheath. These neoplasms are rare among the spindle cell mesenchymal tumors of the gastrointestinal tract, but develop most commonly in the stomach representing 0.2% of all gastric tumors. We present the case of a 57-year-old female patient with a large schwannoma in the stomach that was palpable in the abdomen. She underwent subtotal gastrectomy under suspicion of gastrointestinal stromal tumor (GIST), but post-operative histopathological and immunohistochemical findings showed a fascicular arrangement of spindle cell with pallisading nuclei, and positive for S-100 protein with negative smooth muscle actin (SMA). These results confirmed schwannoma as the diagnosis.
Diagnosis, Differential ; Female ; Gastrointestinal Stromal Tumors/diagnosis ; Humans ; Immunohistochemistry ; Middle Aged ; Neurilemmoma/*diagnosis/metabolism ; S100 Proteins/metabolism ; Stomach Neoplasms/*diagnosis/metabolism

Actins ; metabolism ; Bone Neoplasms ; metabolism ; pathology ; surgery ; Desmin ; metabolism ; Diagnosis, Differential ; Fibrosarcoma ; metabolism ; pathology ; Humans ; Leiomyosarcoma ; metabolism ; pathology ; surgery ; Male ; Middle Aged ; Neurilemmoma ; metabolism ; pathology ; Tibia ; Vimentin ; metabolism

Adolescent ; Brain Neoplasms ; metabolism ; pathology ; Diagnosis, Differential ; Female ; Humans ; Melanoma ; metabolism ; pathology ; Melanoma-Specific Antigens ; metabolism ; Neurilemmoma ; metabolism ; pathology ; S100 Proteins ; metabolism ; Vimentin ; metabolism

No abstract available.
Adult ; Female ; Gastroscopy ; Humans ; Neurilemmoma/*diagnosis/pathology/surgery ; S100 Proteins/metabolism ; Stomach Neoplasms/*diagnosis/pathology/surgery ; Tomography, X-Ray Computed

Aged ; Angiomyolipoma ; metabolism ; pathology ; Diagnosis, Differential ; Humans ; Kidney Neoplasms ; metabolism ; pathology ; surgery ; Leiomyoma ; metabolism ; pathology ; Lymphocytes ; pathology ; Male ; Nephrectomy ; Neurilemmoma ; metabolism ; pathology ; surgery ; S100 Proteins ; metabolism

Intradural schwannoma of the conus medullaris is a rare form of spinal neoplasm, which commonly occurs in the lumbar region. Conus medullaris level is unusual for schwannomas. A 49-year-old woman presented with chronic sciatica, mild bladder dysfunction, and paresthesia in the buttocks. Magnetic resonance imaging of the spine showed a mass lesion in the conus medullaris region with nerve compression. The tumor was completely resected and diagnosed histologically as schwannoma. The patient recovered after surgery. Clinical and radiologic features of this rare tumor are reviewed and are accompanied by literature findings.
Female ; Humans ; Magnetic Resonance Imaging ; Middle Aged ; Neurilemmoma ; diagnosis ; metabolism ; pathology ; surgery ; S100 Proteins ; metabolism ; Spinal Cord Neoplasms ; diagnosis ; metabolism ; pathology ; surgery

Adult ; Diagnosis, Differential ; Follow-Up Studies ; Humans ; Knee Joint ; Male ; Mucin-1 ; metabolism ; Neurilemmoma ; metabolism ; pathology ; surgery ; S100 Proteins ; metabolism ; Sarcoma, Synovial ; metabolism ; pathology ; Sweat Glands

OBJECTIVETo study the morphologic characteristics, immunophenotype and differential diagnosis of a case of microcystic/reticular schwannoma occurring in cervical spine.

METHODSThe pathologic features and immunophenotypic profile of a case of microcystic/reticular schwannoma were studied. Immunohistochemistry was performed using EnVision two-step method.

RESULTSThe patient was a 35-year-old male and presented with a bump over the fifth cervical spine on radiologic check up. Grossly, the bump was gray-white in color, soft, well-circumscribed but non-encapsulated. The tumor measured 3.5 cm × 3.0 cm × 1.8 cm in size. Histologically, it was composed of two distinctive components. One component resembled the conventional schwannoma but showed focally nuclear pleomorphism, reminiscent of changes in degenerating schwannoma. The other component consisted of epithelial-like cells arranged in a reticular or lace-like pattern, amongst a myxoid matrix. Immunohistochemical study showed that the tumor cells were strongly positive for vimentin, S-100 protein, glial fibrillary acidic protein and neuron-specific enolase, focally positive for CD68, CD10 and Ki-67, and negative for pan-cytokeratin, epithelial membrane antigen, neurofilament, carcinoembryonic antigen, smooth muscle actin, estrogen receptor, progesterone receptor and p53.

CONCLUSIONSMicrocystic/reticular schwannoma is a novel variant of schwannoma, arising mainly in internal viscera but seldom in bone. Awareness of this entity is helpful in distinction from chordoma, other mucoid tumors or sarcomas.

Adult ; Cervical Vertebrae ; Chondrosarcoma ; metabolism ; pathology ; Chordoma ; metabolism ; pathology ; Diagnosis, Differential ; Glial Fibrillary Acidic Protein ; metabolism ; Humans ; Male ; Neurilemmoma ; metabolism ; pathology ; surgery ; Phosphopyruvate Hydratase ; metabolism ; S100 Proteins ; metabolism ; Sarcoma ; metabolism ; pathology ; Spinal Neoplasms ; metabolism ; pathology ; surgery ; Vimentin ; metabolism

Adult ; Diagnosis, Differential ; Humans ; MART-1 Antigen ; metabolism ; Magnetic Resonance Imaging ; Male ; Medulloblastoma ; metabolism ; pathology ; Melanocytes ; pathology ; Melanoma ; diagnosis ; metabolism ; pathology ; surgery ; Melanoma-Specific Antigens ; metabolism ; Meningeal Neoplasms ; diagnosis ; metabolism ; pathology ; surgery ; Neoplasms, Multiple Primary ; diagnosis ; metabolism ; pathology ; surgery ; Neurilemmoma ; metabolism ; pathology ; Nevus of Ota ; diagnosis ; metabolism ; pathology ; surgery ; S100 Proteins ; metabolism ; Skin Neoplasms ; diagnosis ; metabolism ; pathology ; surgery ; Vimentin ; metabolism

Adolescent ; Adult ; CD57 Antigens ; metabolism ; Diagnosis, Differential ; Female ; Glial Fibrillary Acidic Protein ; metabolism ; Humans ; Male ; Middle Aged ; Neurilemmoma ; metabolism ; pathology ; Pelvic Neoplasms ; metabolism ; pathology ; Peripheral Nervous System Neoplasms ; metabolism ; pathology ; Retroperitoneal Neoplasms ; metabolism ; pathology ; S100 Proteins ; metabolism