Epithelioid malignant peripheral nerve sheath tumor of the uterine corpus

MPNST of Uterine Round Ligament: A Report of a Surgically Challenging Aggressive Rare Case and Literature Review

MPNSTs (malignant peripheral nerve sheath tumours) arise rarely from the female genital tract, even more rarely from the uterus. A literature review showed 18 cases affecting the uterine cervix, but only four affecting the uterus per se, making our present case the fifth to be involving the uterus, specifically round ligament. It was the first time a uterine lesion (not uterine cervix) was defined in a neurofibromatosis patient. This was a young patient who initially underwent a uterus-sparing surgery for a round ligament tumour which was finally diagnosed to be MPNST. She received adjuvant chemotherapy but recurred with pelvic vascular involvement. A challenging surgery was performed, and the tumour was resected without morbidity. She was followed up with radiotherapy; however, she quickly developed extensive peritoneal disease and succumbed to the disease. High-grade nature of MPNST along with the background of NF could have made the tumour more aggressive, highlighting the importance of suspecting MPNST in spindle cell tumours of pelvis and performing total resection in the first setting.

Recurrent epithelioid malignant peripheral nerve sheath tumor with neurofibromatosis type 1: A case report and literature review

Malignant peripheral nerve sheath tumors (MPNSTs) are unusual and aggressive malignant soft-tissue tumors that comprise 5-10% of all soft-tissue sarcomas. Approximately 50% of MPNST cases are associated with neurofibromatosis type-1 (NF-1). As a rare MPNST subset, the epithelioid variant of MPNST (eMPNST) is histologically characterized by the predominant presence of epithelioid tumor cells, and accounts for <5% of all MPNSTs. In addition, eMPNST is rarely associated with NF-1 when compared with conventional MPNST. Although extensive clinicopathological studies have been conducted on eMPNST, clinicians face difficulty when attempting to make an accurate diagnosis. Subsequently, the biological consequences, including recurrence, metastasis and mortality rate in patients with eMPNST remain unclear. The current study presents the case of a 71-year-old woman with eMPNST and a family history of NF-1 in whom tumors had recurred twice on the lower back. A literature search for eMPNSTs was conducted by browsing PubMed and MEDLINE for English-language articles, as well as references from review articles, and revealed 129 published cases. Only 5 cases of eMPNST were associated with NF-1. The studies were retrospectively reviewed and the clinicopathological data of the patients, including tumor site, treatment, follow-up, prognosis, and immunohistochemical positivity were collected.

Frameless stereotactic volumetric modulated arc radiotherapy of brachial plexus tumours in dogs: 10 cases

OBJECTIVE

Treatment of canine peripheral nerve sheath tumours (PNSTs) is challenging and prognosis after surgical resection is considered poor. The aim of this study was to evaluate the feasibility and effectiveness of stereotactic radiotherapy (RT) of these tumours.

METHODS

10 dogs with clinical symptoms and MRI findings consistent with PNSTs of the brachial plexus, branches and nerve roots were treated with linear accelerator-based volumetric-modulated arc radiotherapy (VMAT) with a dose of 35 Gy/5 fractions. Clinical and MRI follow-up examinations were planned and radiotoxicity and survival times were investigated.

RESULTS

Tumours involved the plexus and proximal nerves in three dogs, the plexus, proximal nerves and nerve roots in five dogs and the nerve roots and proximal nerves in two dogs. Partial response and partial or complete reductions of neurological deficits were observed in all the treated dogs. Local recurrence was observed in 9/10 of treated dogs. No symptom directly referable to radiotoxicity was observed. Mean overall survival of 371 ± 30 days [95% confidence interval (CI) of (315-427)] and mean progression-free survival of 240 ± 30 days (95% CI of 188-291) from this work are comparable with surgical literature data regarding the plexus and proximal nerve localization, but are superior in comparison with nerve root localization.

CONCLUSION

VMAT can be a safe and viable alternative to surgery in cases of canine brachial plexus PNSTs involving the proximal nerves and nerve roots. Advances in knowledge: To our knowledge, this is the first prospective observational clinical study regarding VMAT stereotactic RT treatment for canine brachial plexus PNSTs and suggests that VMAT may achieve at least similar clinical outcome than surgery in a safer way.

Ulnar malignant peripheral nerve sheath tumour diagnosis in a mixed-breed dog as a model to study human: histologic, immunohistochemical, and clinicopathologic study

Canine Malignant Peripheral Nerve Sheath Tumors (MPNSTs) are uncommonly reported in the ulnar, since they are underestimated relative to the more common spindle cell tumours of soft tissue. In dogs, MPNST accounts for 27% of nervous system tumours. In man, MPNST represents 5-10% of all soft tissue sarcomas and is often associated with neurofibromatosis type 1 (NF-1).An 8-year-old, 9 kg, female mixed-breed dog with a subcutaneous mass on the upper right side of the ulnar region was presented to the small animal research and teaching hospital of Tehran University. The dog was anorexic with general weakness. The mass (7 × 4 cm) was removed surgically and processed routinely. Microscopically, the mass was composed of highly cellular areas with a homogeneous population of round or spindle cells, high cellular pleomorphism, high mitotic index and various morphologic patterns. Furthermore, spindle cells arranged in densely or loosely sweeping fascicles, interlacing whorls, or storiform patterns together with wavy cytoplasm, nuclear palisades, and round cells were arranged in sheets or cords with a meshwork of intratumoral nerve fibers. In addition, in this case the presence of neoplastic cells within the blood vessels was observed. Immunohistochemically, tumor was positive for vimentin and S-100 protein. The histopathologic features coupled with the S-100 and vimentin immunoreactivity led to a diagnosis of malignant neurofibroma.

To the best of our knowledge, primary ulnar MPNST has not been reported in animals. This is the first documentation of an ulnar malignant peripheral nerve sheath tumour in a dog.

Excellent response of malignant peripheral nerve sheath tumour of retroperitoneum to radiation therapy

Malignant peripheral nerve sheath tumours are high-grade sarcomas originating from Schwann cells or nerve sheath cells. Most of these tumours are associated with major nerves of the body wall and extremities. The lower extremity and the retroperitoneum are the most common sites. Surgery is the cornerstone of treatment, however, radiation therapy is usually used as an adjuvant treatment. In this paper we present a 57-year-old Iranian woman with malignant peripheral nerve sheath tumour of retroperitoneum who was operated subtotally and then underwent radiation therapy which led to disappearance of all gross residual disease.

Sporadic haemangioblastoma of the kidney with rhabdoid features and focal CD10 expression: report of a case and literature review

We present here an intriguing case of sporadic renal haemangioblastoma occurring in a 61-year-old male. The tumor consisted of nests of polygonal cells and abundant capillary networks. The neoplastic cells generally showed abundant eosinophilic cytoplasm and prominent eccentric nuclei, resembling the rhabdoid cells. Pronounced intranuclear cytoplasmic pseudoinclusions were another significant feature seen. NSE, a-inhibin and S100 were positive in tumor cells and particularly, focal CD10 expressions were observed. This is possibly the first reported case of a haemangioblastoma showing a rhabdoid phenotype and CD10 immunopositivity. Malignant rhabdoid tumor and renal cell carcinoma with rhabdoid features were probably the most challenging mimics need to be differentiated. The result of focal CD10 staining in our case may further lead to confusion with renal cell carcinoma. To avoid misdiagnosis, more considerations should be attached to the rare neoplasm.

VIRTUAL SLIDES

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