Clinical Findings and Outcome in 30 Dogs with Presumptive or Confirmed Nerve Sheath Tumors.

Nerve sheath tumors (NSTs) are well-recognized primary nervous system tumors, but there is relatively limited information in dogs including comparison of NSTs in different anatomical locations. This retrospective study describes the clinical features and outcomes in a group of dogs with NSTs affecting the cranial nerves or spinal nerves. Thirty dogs were included, 25 with a presumptive diagnosis and five confirmed by histopathologic analysis. Seven dogs also had cytology of tumor samples, which were supportive of the NST diagnosis in four. Eight dogs had cranial nerve-associated NSTs, with six involving the trigeminal nerve. Twenty-two dogs had spinal nerve-associated NSTs including 13 invading the spinal canal and nine peripheral to the spinal canal, with the majority affecting nerves or nerve roots of the brachial plexus. The prognosis was poor, with dogs being euthanized eventually because of disease progression. Among dogs alive 1 week after diagnosis, the median survival time was 4 months but ranged from 2 weeks to >2 years. While there was a broad overlap between NST locations, survival was generally longer for dogs without spinal canal or intracranial involvement. The results expand available information on NSTs in dogs but should be interpreted with caution given the small number of dogs with a definitive diagnosis. Further investigation is warranted to determine how tumor location, invasiveness, and treatments pursued impact outcome.

Malignant nerve sheath tumor of oculomotor nerve in a pediatric patient.

Malignant nerve sheath tumors are extremely rare pathologies. They tend to occur within peripheral nerves and have close association of neurofibromatosis disease. Here, we present the second case of MNST of oculomotor nerve in literature. The patient was a 2-year-old girl with left sided oculomotor nerve palsy. After resection, the patient immediately had chemotherapy and radiotherapy. One year after surgery disease progressed with extensive intracranial seedings, and she passed away.

Malignant peripheral nerve sheath tumor: A rare malignancy.

Malignant peripheral nerve sheath tumor (MPNST) is also termed as spindle cell malignancy of the peripheral nerve Schwann cell. It is a rare and highly aggressive, soft-tissue sarcoma of ectomesenchymal origin that accounts for 10% of all sarcomas and only 10%-12% of all lesions occur in the head-and-neck region, thus making it a rare entity. It arises de novo or from the preexisting benign neurofibroma. The diagnosis of MPNST is one of the most elusive among the soft-tissue tumors because of its greater variability in overall presentation both clinically and histologically. This difficulty can be overcome by the use of immunohistochemistry. This article presents a rare case of MPNST of the oral cavity in a 40-year-old female patient with a brief review of the current literature.

Rapid Redistribution of an Acute Traumatic Epidural Hematoma in a Patient with Invasive Skull Cancer.

The rapid spontaneous resolution of an acute epidural hematoma (EDH) has rarely been reported. A possible mechanism of spontaneous resolution is egress of the hematoma into the subgaleal space through a skull fracture. We report a case of rapid redistribution of an acute EDH in a 37-year-old man who had a malignant peripheral nerve sheath tumor of the skull and who slipped and fell when going to the bathroom. A huge EDH without a skull fracture developed in the left parieto-occipital area. The acute EDH was completely alleviated and a newly developed intracerebral hematoma was found on a brain computed tomography scan that was acquired the day after the trauma. Given these findings, a fractured skull and increased pressure in the intradural area may have been the mechanisms underlying the redistribution of the hematoma.

PET in the Diagnostic Management of Soft Tissue Sarcomas of Musculoskeletal Origin.

Soft tissue sarcomas (STSs) account for less than 1% of adult solid tumors and about 7% of pediatric malignancies, causing 2% of cancer-related deaths. With the advent of PET-computed tomography (CT), the value of (18) fluorine-2-fluoro-2-deoxy-d-glucose (FDG) PET imaging to improve the management of STSs has been explored. FDG PET imaging has been found useful in restaging and treatment response assessment. This article reviews current knowledge and application of FDG PET-CT in initial diagnosis, staging, restaging, treatment response monitoring, and prognosis, with a brief overview of the most common histologic subtypes of STS.

Malignant peripheral nerve sheath tumor arising in the setting of cervical nerve root schwannomas.

We present a 23-year-old woman who was diagnosed with a malignant peripheral nerve sheath tumor (MPNST), 17 months following the resection of a schwannoma. MPNST is rare and is usually associated with neurofibromatosis. The typical treatment of resection and radiation is difficult to achieve in the spine.

Malignant nerve sheath tumor of the spinal accessory nerve: a unique presentation of a rare tumor.

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs), sarcomas originating from tissues of mesenchymal origin, are rare in patients without a history of neurofibromatosis. CASE REPORT: We report a case of an MPNST of the spinal accessory nerve, unassociated with neurofibromatosis, which metastasized to the brain. The tumor, originating in the intrasternomastoid segment of the spinal accessory nerve, was removed. Two years later, the patient presented with focal neurological deficits. Radiographic findings revealed a well-defined 2.2×2.2×2.2 cm, homogeneously enhancing mass in the left parieto-occipital region of the brain surrounded by significant vasogenic edema and mass effect, culminating in a 1-cm midline shift to the right. The mass was surgically removed. The patient had nearly complete recovery of vision, speech, and memory. CONCLUSIONS: To our knowledge, this is the first documented case of an MPNST arising from an extracranial segment of the spinal accessory nerve and metastasizing to the brain.