Cutaneous sclerosing perineurioma of the digit

An 11-year-old Japanese girl noticed a small nodule, with mild tenderness, on the right index finger 5 years before visiting our outpatient clinic. She had no familial history of neurofibromatosis or past history of traumatic injury at the site of the tumor. Physical examination revealed a slightly elevated, subcutaneous, nodular tumor in the volar aspect between the proximal and distal interphalangeal joints of the digit (Fig. 1A). By magnetic resonance imaging examination, the tumor showed low density on both T1- and T2-weighted images, and was located just adjacent to the tendon with no invasive signs. The tumor was extirpated; at operation, it was well circumscribed and mobile without adhesion to adjacent tendon or nerve, and was easily removed. Grossly, the tumor was a well-circumscribed, firm nodule (10 mm x 8 mm x 5 mm in size) (Fig. 1B). The cut surface was whitish, homogeneous, and solid without cystic lesions. Histologically, it was an unencapsulated, paucicellular dense, fibrous nodule with a concentric circular arrangement of collagen bundles (Fig. 2A). Amongst the fibrous bundles, a small number of ovoid/epithelioid or plump spindle cells were arranged in a corded, trabecular, or whorled (onion bulb-like) pattern (Fig. 2B); a storiform pattern was not noted. These cells were relatively uniform and had a somewhat elongated, slightly hyperchromatic nucleus with fine granular chromatin. Neither nuclear pleomorphism nor multinucleated cells were evident, and necrosis and mitotic figures were not observed. Periodic acid-Schiff (PAS) stain after diastase digestion highlighted the corded or whorled pattern of the tumor cells by encasing them. For immunohistochemical examination, formalin-fixed, paraffin-embedded serial tissue sections were stained by a labeled streptavidin-biotin method. The tumor cells were positive for vimentin and epithelial membrane antigen (EMA) (Fig. 3A), and negative for pan-cytokeratin, carcinoembryonic antigen (CEA), CD34, alpha-smooth muscle actin, desmin, and CD68. Type IV collagen and laminin (Fig. 3B) were detected along the cords or whorls of the tumor cells, similar to the staining pattern of the diastase-PAS reaction. Schwann cells and axonal components, immunoreactive for S100 protein and neurofilament, respectively, were focally detected just adjacent to the cords or whorls, although the tumor cells per se did not express these proteins. Consequently, the tumor was found to be perineurial in origin and was diagnosed as cutaneous sclerosing perineurioma.

Primary malignant peripheral nerve sheath tumor of the lung in a young child without neurofibromatosis type 1

Malignant peripheral nerve sheath tumors (MPNST) are uncommon in children and almost half of the cases occur in patients with neurofibromatosis 1 (NF1). We report a child with a primary MPNST of the lung without NF1. MPNST of the lung has similar clinical and radiologic characteristics as pleuropulmonary blastoma. We suggest to include MPNST of the lung in the differential diagnosis of intrapulmonary masses in children.

The value of magnetic resonance imaging in the differentiation between malignant peripheral nerve-sheath tumors and non-neurogenic malignant soft-tissue tumors

OBJECTIVE

To assess the sensitivity and specificity of MRI criteria in the differentiation between malignant peripheral nerve sheath tumors (MPNST) and non-neurogenic malignant soft-tissue tumors (MSTT).

DESIGN AND PATIENTS

MRI examinations of 105 patients with pathologically proven malignant soft-tissue lesions (35 MPNST and 70 MSTT) were retrospectively reviewed, the reviewers being unaware of the pathological diagnosis. Using a standardized protocol, the tumors were evaluated for multiple parameters regarding morphology and appearance on different sequences before and after gadolinium contrast administration (location, distribution, delineation, homogeneity, size, shape, relationship to bone and neurovascular bundle, intralesional hemorrhage, necrosis, perilesional edema, lymphangitis and signal intensities). Results were compared using a chi-square or Fisher's exact test.

RESULTS

MRI findings suggestive of MPNST (p<0,05) were intermuscular distribution, location on the course of a large nerve, nodular morphology, and overall non-homogeneity on T1-weighted images, T2-weighted images and T1-weighted images after gadolinium contrast injection. MRI findings in favor of MSTT were intramuscular distribution, ill-delineated appearance of more than 20% of the lesion's circumference, and presence of intralesional blood vessels, perilesional edema and lymphangitis. There is no significant difference for degree and pattern of enhancement after gadolinium contrast injection, nor for presence of bone involvement or cystic or necrotic areas.

CONCLUSION

MRI provides several features that contribute to the differentiation between MPNST and non-neurogenic malignant soft-tissue tumors. MRI findings suggestive of MPNST should be helpful to pathologists in the strategy for further examination.

Paratesticular malignant peripheral nerve sheath tumour: a case report

Primary malignant peripheral nerve sheath tumours (MPNST) of intrascrotal extra testicular site are extremely rare with only few cases reported in literature. These are highly malignant tumours most often associated with neurofibromatosis. The incidence in general population is 0.001%. A 35-year-old male presented with swelling of the scrotal sac of three months duration. There were no features of neurofibromatosis. The lesion was excised and was diagnosed as MPNST. The patient developed recurrence within two months.

Atypical and malignant peripheral nerve-sheath tumors of the brachial plexus: report of three cases and review of the literature

Tumor involvement of the brachial plexus is uncommon. The most common intrinsic neoplasms involving the brachial plexus are benign neurilemmomas and neurofibromas that are usually associated with neurofibromatosis-1 (NF-1). Solitary neurofibromas unassociated with NF-1 are very uncommon. Malignant peripheral nerve-sheath tumors (MPNST) are rare at this site, arising spontaneously or in the context of NF-1. This presentation discusses the clinical presentation, pathology, and management of these tumors, which usually occur in young adults. MPNST are intermediate or high-grade sarcomas with a high risk of local and distant spread. Approximately 50% of MPNST arise in patients with NF-1, and therefore these patients should be thoroughly investigated for any new symptoms or masses. MPNST of the brachial plexus should be treated with an adequate wide local excision, with adjuvant high-dose radiotherapy pre- or postoperatively. The role of chemotherapy in the treatment of MPNST is not clearly defined, but it may have some benefit in salvaging treatment failures.

Biopsy of deep-seated head and neck lesions under intraoral ultrasound guidance

Although transcutaneous ultrasound combined with fine-needle aspiration is often used as initial modality for evaluating superficial neck masses, its role in management of deep-seated neck masses is limited. Intraoral ultrasound and guided biopsy helps in obtaining tissue from deep-seated neck masses for an accurate histologic diagnosis, providing useful information in treatment planning. This article discusses the role of intraoral ultrasound and presents 3 cases in which biopsy of deep-seated neck masses under intraoral ultrasound guidance helped in diagnosis and management.

Malignant triton tumour of the thigh—A retrospective analysis of nine cases

Malignant triton tumour (MTT) is a very rare soft tissue tumour.

AIM

To report nine patients diagnosed with malignant triton tumour of the thigh between January 1996 and January 2005 to determine the natural history and factors that may affect survival in this aggressive tumour.

METHODS

Due to the association of Neurofibromatosis (NF Type I) with malignant triton tumour, two groups of patients were identified: those with NF type I (Group I cases); and those without (Group II).

RESULTS

Group I patients accounted for four cases and arose predominantly in young males, all tumours being high grade, >10 cm in size and all four patients died within two years of diagnosis. By contrast, the five patients of Group II were older, had smaller size and lower grade tumours and three patients are long-term survivors.

CONCLUSION

Although the number of cases is small, our data supports the views that the natural history of MTT is more aggressive in patients with NF type I. This poor outlook could be attributed to the high frequency of Grade III histology in this disease and the large tumour size.

[Intracranial and intramedullary peripheral nerve sheath tumours. Case reports from 20 autopsies]

INTRODUCTION

Tumors arising from the sheath of peripheral nerves, both intracranial and intraspinal, are uncommon and are sometimes of difficult clinical diagnosis, especially when they occur in unusual sites. Schwannomas, neurofibromas and perineuromas are depicted in this descending order of frequency. Most are sporadic and some can be part of hereditary syndromes. Histological malignancy of this neoplasm is rare.

MATERIALS AND METHODS

The clinical and pathological findings of 20 autopsy cases of intracranial and intraspinal peripheral nerve tumors are analyzed. The average age at presentation was 35 years and the male/female ratio was 1:1.

RESULTS

19 were schwannomas, 13 of the 8th cranial nerve (two associated with neurofibromatosis type 2), two originated in the trigeminal and one in the 12th nerves. Three were intraspinal, one of this underwent malignant changes and was part of neurofibromatosis type 1 (NF-1), another was an intraspinal lumbar mass with schwannomatosis and the third was a case of multiple intraspinal neurofibromas as a part of NF-1. 14 cases were surgically treated and the causes of death were ischemic lesions due to the large size of the tumors. The correct clinical diagnosis was made in 14 patients. In 11 instances there was corroboration by biopsy. Three were misdiagnosed and three were autopsy findings.

CONCLUSIONS

In this series more cases were sporadic. No sex predominance was encountered. The importance of early detection on intracranial and intraspinal peripheral tumors is paramount, since the large size of these histologically benign neoplasms makes them biologically malignant.

Role for surgery as adjuvant therapy in optic nerve sheath meningioma

PURPOSE

To describe a role for optic nerve decompression as adjuvant surgical therapy in the management of optic nerve sheath meningioma in patients with severe, progressive visual loss and optic disc edema before or after radiation therapy.

METHODS

Interventional case report.

RESULTS

Two patients with unilateral optic nerve sheath meningioma had progressive visual loss (20/200 and no light perception) and disc edema. The first had previously undergone fractionated stereotactic radiotherapy and the second subsequently was treated with fractionated stereotactic radiotherapy after decompression surgery. After excision of a dural window and biopsy of the tumor from the nerve sheath, visual acuity improved to 20/25 and 20/200, respectively, both coinciding with resolution of disc edema.

CONCLUSIONS

In patients with optic nerve sheath meningioma with severe disc edema and rapid vision loss, surgery may serve an important but restricted, adjuvant role to radiation therapy under special conditions.

Cervicothoracic malignant peripheral nerve sheath tumor in a 12-year-old girl with neurofibromatosis type 1

We encountered a 12-year-old girl with neurofibromatosis type 1 (NF1) who developed a low-grade cervicothoracic malignant peripheral nerve sheath tumor (MPNST). Computed tomography of the neck showed an elastic firm tumor measuring 7 x 6 x 4 cm and arising from the upper mediastinum. She had no pain or neurological symptoms, but the tumor enlarged to ca. 8 x 8 x 4 cm over the following 7 months. Although we had diagnosed a neurofibroma by preoperative incisional biopsy, the resected tumor showed low-grade MPNST in the central portion of the tumor. In treating a tumor in a patient with NF1, we must recognize that partial biopsies do not necessarily establish a definitive diagnosis and that a growing tumor may indicate malignant transformation.

Identification of a novel amplicon at distal 17q containing theBIRC5/SURVIVINgene in malignant peripheral nerve sheath tumours

Previous studies have suggested that amplification of genes, notably the TOP2A gene, on chromosome arm 17q may be important for the development of malignant peripheral nerve sheath tumour (MPNST). In order to study the frequency, distribution, and chromosomal organization of rearrangements at 17q, interphase and metaphase fluorescence in situ hybridization (FISH) were used to evaluate copy number changes at 17q in 28 MPNSTs. Increased copy numbers were seen for the ERBB2 and TOP2A genes in eight and nine cases, respectively, supporting a potential role for these two genes in MPNST tumourigenesis. Net gain of distal 17q material was observed in 16 of the 28 MPNSTs, with high-level gain in three cases, and was associated with poor outcome. Among the 26 patients for whom follow-up data were available, gain of distal 17q was present in 11 of 12 tumours that had metastasized, compared with 4 of 14 of those that had not metastasized. Detailed FISH mapping analysis of metaphase spreads identified a 2 Mb commonly gained/amplified region at 17q25. Among the genes mapping to this region, BIRC5, which encodes the baculoviral IAP repeat-containing protein 5/survivin protein, is a strong candidate target gene for amplification, as it has been previously shown to be overexpressed in neurofibromatosis type 1-associated MPNST. Three other genes that co-amplified with BIRC5 represent other potential candidate genes: PTDSR involved in apoptosis; SEPT9 overexpressed in human malignant brain tumours; and SOCS3 involved in cell survival and differentiation of neurons.

A cytogenetic analysis in two cases of malignant peripheral nerve sheath tumor showing hypodiploid karyotype

In this study, we report cytogenetic findings in two cases of malignant peripheral nerve sheath tumor (MPNST) with hypodiploid karyotypes. A G-band technique, multicolor fluorescence in situ hybridization (m-FISH) and comparative genomic hybridization (CGH) were used and compared in this investigation. In both tumors, the G-band and m-FISH analysis demonstrated multiple rearrangements on chromosomes 1-5, 8-12, 15-17, 20 and 21, whereas CGH exhibited gains at 8q and 4q. Both of the structural aberrations and the genomic imbalances of the chromosomes may play an important role in the pathogenesis and development of MPNST. No cytogenetic abnormalities specific for MPNST were found in the present cases or in other previously reported cases. This may reflect the diversity or heterogeneity of MPNST that exhibit various clinical and histological features. However, there are few cases described in detail on a morphologic pattern of MPNST, a correlation between the cytogenetic aberrations and the histologic patterns are still uncertain.

Functional analysis and molecular modeling show a preserved wild-type activity of p53C238Y

In human tumors, p53 is often disabled by mutations in its DNA-binding domain and is thus inactive as a transcription factor. Alternatively, MDM2 gene amplification or up-regulation represents a mechanism of p53 wild-type inactivation, mainly reported in soft tissue sarcomas. In a previous TP53 analysis carried out on sporadic and NF1-related malignant peripheral nerve sheath tumors, in two cases, we observed the occurrence of C238Y missense mutation, leading to p53 stabilization unexpectedly coupled with immunophenotypic MDM2 overexpression. To investigate this TP53 missense mutation not yet functionally characterized in mammalian cell, we did MDM2 Southern blot and p53(C238Y)/MDM2 biochemical and functional analyses followed by molecular modeling. The results showed a lack of MDM2 gene amplification, evidence of p53-MDM2 protein complexes, and presence of a p53 that retains the ability to become phosphorylated on Ser15 and to induce the transcription of p21(waf1). Additional molecular modeling data highlighted the structural similarities between p53(C238Y) and wild-type p53, further supporting that the p53(C238Y) mutant still retains functional wild-type p53 properties.

Sclerosing perineurioma: Tumor of the hand with a short T2

We present two cases of sclerosing perineurioma, a rare soft tissue tumor, in the palm and the ring finger respectively, presenting as a small, painless and subcutaneous mass. This tumor has a predilection for the digits and palms of young, predominantly male adults. In the present cases the tumors showed very low signal intensity on T2-weighted magnetic resonance (MR) images. Histologically they contained abundant collagen and hyalinized stroma, which would account for areas of low signal intensity on T2-weighted MR images. Immunohistochemically, the tumor cells were positive for vimentin, epithelial membrane antigen and human erythrocyte glucose transporter 1 and negative for S-100 protein. To the best of our knowledge, the appearance of sclerosing perineurioma on MR imaging has not been previously reported in the English-language literature. Sclerosing perineurioma should be considered in the differential diagnosis of hand tumors when the tumor shows low signal intensity on T2-weighted MR images.

Neurofibroma with psammoma bodies

Neurofibromas are benign tumours of the nerve sheath. Histologically they vary depending on their contents of cells, myxoid stroma and collagen. A 41-year old male with radicular pain had a tumour involving the posterior chest wall. Microscopically it resulted to be a neurofibroma with abundant psammoma bodies. Although these bodies are very frequent in some neoplasias, to our knowledge they have not been described in neurofibromas to date.

Brachial plexopathy due to malignant peripheral nerve sheath tumor in neurofibromatosis type 1: case report and subject review

Neurofibromatosis type 1 (NF1) is a common tumor predisposition syndrome affecting approximately 1 in 4,000 persons. It is an autosomal-dominant disorder with half of the cases resulting from spontaneous mutations. This genetic defect leads to the formation of benign tumors or neurofibromas of the peripheral nervous system. Dermal neurofibromas may cause local discomfort and itching but are rarely associated with neurological deficit and do not undergo malignant change. The more extensive plexiform neurofibromas produce neurological complications in 27%-43% of patients with NF1 and may undergo malignant degeneration in 5% of cases. Patients with NF1 who develop pain or new neurological symptoms should have a rapid and thorough assessment for malignancy. In this report, we illustrate this point by presenting a patient who developed acute shoulder pain and weakness due to malignant degeneration of a plexiform neurofibroma involving the left brachial plexus, and review the literature on this subject.

Malignant peripheral nerve sheath tumors of the head and neck: two cases and a review of the literature

Malignant peripheral nerve sheath tumors are uncommon lesions that occasionally affect the head and neck. We describe 2 new cases of head and neck pathology. One tumor involved the parotid gland and resulted in erosion of the temporal bone, and the other affected the lower lip. A rapid diagnosis has significant implications for management because of the tumor's potential for aggressive behavior and its high rate of recurrence. To the best of our knowledge, lip involvement is rare and temporal bone involvement has not been previously described.

Post-radiation intramedullary malignant peripheral nerve sheath tumor

We report the intramedullary growth of a malignant peripheral nerve sheath tumour (MPNST). A 50year-old man developed a severe tetraparesis over a 4-month period. Following irradiation of a chronic tonsillitis during his childhood, the patient had later experienced a number of post-radiation diseases, including a laryngeal cancer that required permanent tracheotomy. Before admission, a magnetic resonance imaging (MRI) study had disclosed a C4-C5 intramedullary lesion. On admission to our Department, the patient had a nearly complete tetraparesis. At surgery, the lesion was exposed through a posterior midline myelotomy. A friable neoplasm, with no clear plane of cleavage, was found. The tumour was subtotally resected. Histological examination, which intraoperatively had not yielded a specific diagnosis, eventually revealed a MPNST, grade intermediate, with ultrastructural and immunohistochemical features consistent with a schwannian differentiation. No postoperative radiotherapy was undertaken. The patient died 9 months later from pneumonial complications. MPNSTs may develop within the spinal cord similarly to their benign schwannian counterpart. The reported sequence of events might support a possible relation between irradiation of the spinal cord and induction, followed by malignant transformation, of intramedullary schwannosis. This unique case must be added to the growing list of radiation-induced spinal cord tumours.

Neurofibromatosis types 1 and 2

BACKGROUND

Neurofibromatosis types 1 and 2 (NF1 and NF2) are autosomal dominant neurocutaneous disorders with some similarities and many differences. They are frequently discussed together and often confused for one another by clinicians. Both disorders have widely variable presentations and degrees of severity. A thorough understanding of these complex disorders is essential for proper medical management, anticipatory care, and patient education.

REVIEW SUMMARY

In this article, the clinical features, genetics, pathogenesis, and management of neurofibromatosis types 1 and 2 are reviewed and compared.

CONCLUSIONS

NF1 and NF2 are complex genetic disorders with numerous manifestations and wide phenotypic variability. The complex nature of these disorders requires coordinated multidisciplinary care.

Myxoid variant of adrenocortical carcinoma: report of a unique case

Myxoid variant of adrenocortical carcinomas (ACC) are rare, there being only 11 cases in the literature to date. Reported herein are the findings of a case, which in contrast to all previously reported myxoid ACC, was devoid of typical non-myxoid areas. The patient was a 61-year-old man in whom a left adrenal mass was detected during investigation of Cushing's syndrome. The adrenal was replaced by malignant cells and expanses of myxoid material. The cells were positive for melan-A, synaptophysin, vimentin and alpha-inhibin. The ultrastructural features of the cells were typical of adrenal cortical differentiation. The differential diagnosis of myxoid ACC includes extraskeletal myxoid chondrosarcoma, chordoma, myxoid adenocarcinoma, myxoma, lipomatous tumors, nerve sheath tumors, smooth muscle tumors, gastrointestinal stromal tumor and other sarcomas. The presence of myxoid material in a retroperitoneal lesion raises a broad differential diagnosis in which myxoid adrenocortical neoplasms should be included. Clinicoradiological correlation may be helpful, but special stains, immunohistochemistry and ultrastructural examination may be necessary to establish the diagnosis.