Diagnosis and management of neurofibromatosis type 1

Treatment for paraplegia due to severe kyphoscoliosis associated with neurofibromatosis type 1 via halo-pelvic traction: a case report

BACKGROUND

A sharply angular thoracic deformity, commonly seen in dystrophic scoliosis associated with neurofibromatosis type 1, can compress the spinal cord and potentially cause neurological impairment. However, managing paraplegia due to severe kyphoscoliosis associated with neurofibromatosis type 1, coupled with low body mass index and extremely severe kyphoscoliosis, presents a significant challenge.

CASE PRESENTATION

A 13-year-old girl of Mongolian ethnicity with severe dystrophic kyphoscoliosis associated with neurofibromatosis type 1 presented with paraplegia and dyspnea. Preoperative radiograph imaging revealed the presence of a thoracic kyphosis and scoliosis, with a Cobb angle of 150° and 130°, respectively. A two-stage strategy was devised, comprising halo-pelvic traction and spinal fusion with pedicle screws. The neurological deficit showed gradual improvement and ultimately complete recovery during the distraction phase. The curve decreased to an acceptable level, and posterior pedicle screws were implanted and fused without osteotomy. Postoperatively, the hunchback was no longer visible. There were no complications associated with halo-pelvic traction. At the 3-year follow-up, the correction angle and trunk balance were well maintained.

CONCLUSION

It is possible that neurological deficit resulting from severe scoliosis may be reversed following the correction of the spinal curvature. The application of halo-pelvic traction generates substantial corrective forces, facilitating the correction of severe spinal deformities in a gradual and secure manner. A two-stage treatment strategy for patients with severe kyphoscoliosis in neurofibromatosis type 1 may offer an alternative approach to correcting the severe curve while avoiding the potential complications associated with a rapid, one-stage correction.

Maintaining Engagement in Adults with Neurofibromatosis Type 1 to Use the iCanCope Mobile Application (iCanCope-NF)

INTRODUCTION

Neurofibromatosis Type 1 (NF1) is an autosomal dominant genetic condition in which chronic pain is a predominant issue. Given the rarity of the disease, there are limited psychosocial treatments for individuals with NF1 suffering with chronic pain. Using mobile applications can facilitate psychosocial treatments; however, there are consistent issues with engagement. Utilizing a mixed methodology, the current study evaluated the customized iCanCope mobile application for NF1 on increasing engagement through the usage of contingency management.

METHODS

A mixed methods study from a subset of data coming from a randomized clinical trial that occurred from January 2021 to August 2022 was undertaken. Two groups (iCC and iCC + CM) were exposed to the customized iCanCope mobile application in which engagement data were captured in real-time with daily check-ins for interference, sleep, mood, physical activity, energy levels, goal setting, and accessing article content (coping strategies). Additionally, semi-structured interviews were conducted to gain insight into the participants' experience at the end of the trial.

RESULTS

Adults (N = 72) were recruited via NF patient advocacy groups. Significant differences were noted between the groups in total articles read (p = 0.002), goals achieved (p = 0.017), and goals created (p = 008). Additionally, there were significant differences observed between user-generated goals and those that were app recommended (p < 0.001). Both groups qualitatively reported positive feedback on the customized mobile application, indicating that continued usage and engagement of the mobile application were acceptable.

CONCLUSIONS

Employing customized mobile applications for adults with NF1 along with contingency management can leverage self-managed pain treatments while providing auxiliary resources to this population.

Fatal Retroperitoneal Bleeding in Neurofibromatosis Type 1: A Clinically Occult Complication

ABSTRACT

Neurofibromatosis type 1 (NF1) is a common, autosomal dominant neurocutaneous syndrome. The most frequent clinical manifestations include multiple neurofibromas, café-au-lait spots, dystrophic scoliosis, benign and malignant peripheral nerve sheath tumors, and paragangliomas. Neurofibromatosis type 1 vasculopathy is a less well-recognized constellation of vascular pathologies that can cause significant medical complications in patients with NF1. A rare manifestation of this process is neurofibroma infiltration of vasculature with resultant bleeding. The case presented herein illustrates a rare example of a massive fatal hemorrhage due to disruption of a large paraspinal artery in the setting of a diffuse, infiltrative neurofibroma. This case highlights the potential of benign neurofibromas to infiltrate major blood vessels, leading to extensive bleeding and death.

Intestinal Mucosa-Associated Lymphoid Tissue Lymphoma Transforming into Diffuse Large B-Cell Lymphoma in a Young Adult Patient with Neurofibromatosis Type 1: A Case Report

Background: Neurofibromatosis type 1 (NF1) is a hereditary cancer syndrome characterized by multiple café-au-lait macules on the skin. Lymphoproliferative malignancies associated with NF1 are limited, although the most common are brain tumors. Case presentation: A 22-year-old woman with NF1 was admitted due to abdominal pain and bloody diarrhea. Her laboratory data exhibited macrocytic anemia and elevated IgA levels. Image studies showed diffuse increased wall thickening in the transverse and descending colon without lymphadenopathy and hepatosplenomegaly. A colonoscopy revealed a hemorrhagic ulcerated mass. Pathological analysis of the tumor tissues confirmed IgA-expressing mucosa-associated lymphoid tissue (MALT) lymphoma with histological transformation. Moreover, whole-exome sequencing in tumor tissues and peripheral blood mononuclear cells identified a somatic frameshift mutation of the A20 gene, which represents the loss of function. The patient responded well to R-CHOP chemotherapy, but the disease relapsed after 1 year, resulting in a lethal outcome. Conclusions: MALT lymphoma in children and young adults is extremely rare and is possibly caused by acquired genetic changes. This case suggests a novel association between hereditary cancer syndrome and early-onset MALT lymphoma.

Off-label uses of denosumab in metabolic bone diseases

Denosumab (Dmab), a monoclonal antibody against the receptor activator of nuclear factor-κB (RANK) ligand (RANKL) which substantially suppresses osteoclast activity, has been approved for the treatment of common metabolic bone diseases, including postmenopausal osteoporosis, male osteoporosis, and glucocorticoid-induced osteoporosis, in which the pathway of the RANK/RANKL/osteoprotegerin is dysregulated. However, the imbalance of RANKL/RANK/osteoprotegerin is also implicated in the pathogenesis of several other rare metabolic bone diseases, including Juvenile Paget disease, fibrous dysplasia, Hajdu Cheney syndrome and Langerhans cell histiocytosis, thus rendering Dmab a potential treatment option for these diseases. Dmab has been also administered off-label in selected patients (e.g., with Paget's disease, osteogenesis imperfecta, aneurysmal bone cysts) due to contraindications or unresponsiveness to standard treatment, such as bisphosphonates. Moreover, Dmab was administered to improve hypercalcemia induced by various diseases, including primary hyperparathyroidism, tuberculosis and immobilization. The aim of this review is to summarize existing evidence on off-label uses of Dmab in metabolic bone diseases and provide opinion for or against its use, which should be always considered on an individual basis.

Efficacy of denosumab therapy for neurofibromatosis type 1 with osteoporosis and history of fractures: a case report

Background

The natural history and pathogenesis of the skeletal abnormalities found in neurofibromatosis type 1 (NF1) are poorly understood, and the therapeutic options for these manifestations remain limited. This report first describes the clinical outcomes of denosumab treatment for a patient with NF1 suffering from osteoporosis.

Methods

We enrolled a patient with NF1 under denosumab treatment for osteoporosis, prior fractures, and no improvement in bone mineral density (BMD) over 3 years of alendronate therapy. BMD was monitored by dual-energy X-ray absorptiometry. Tested laboratory data included bone-specific alkaline phosphatase, urinary type I collagen amino-terminal telopeptide, tartrate-resistant acid phosphatase 5b, 1-alpha, 25-dihydroxyvitamin D₃, and parathyroid hormone. BMD and laboratory data were evaluated before, between 2 and 4 months, and at 6, 12, 18, and 24 months of treatment.

Case presentation

During 2 years of denosumab therapy for osteoporosis in a 58-year-old female NF1 patient with prior fractures, BMD increased by 6.5% in the lumbar spine and 10.6% in the total hips, and bone turnover markers were notably improved. No fractures occurred during the latter half of treatment.

Conclusion

Denosumab represents an effective treatment option for osteoporosis in NF1 patients.

A Giant Lumbar Pseudomeningocele in a Patient with Neurofibromatosis Type 1: A Case Report

This is a rare case of giant lumbar pseudomeningocele with intra-abdominal extension in patient with neurofibromatosis type 1 (NF1). The patient's clinical course is retrospectively reviewed. A 34-year-old female affected by NF1 was referred to our institution for persistent low back pain and MRI diagnosis of pseudomeningocele located at L3 level with paravertebral extension. From the first surgical procedure by a posterior approach until the relapse of the pseudomeningocele documented by MRI, the patient underwent two subsequent posterior surgical procedures to repair the dural sac defect with fat graft and fibrin glue. One month after the third operation, the abdominal MRI showed a giant intra-abdominal pseudomeningocele causing compression of visceral structures. The patient was asymptomatic. The pseudomeningocele was treated with an anterior abdominal approach and the use of the acellular dermal matrix (ADM) sutured directly on the dural defect on the anterolateral wall of the spinal canal. After six months of follow-up the MRI showed no relapse of the pseudomeningocele. Our case highlights the possible use of ADM as an effective and safe alternative to the traditional fat graft to repair challenging and large dural defects.

Endovascular Internal Trapping of Ruptured Occipital Artery Pseudoaneurysm Associated with Occipital-Internal Jugular Vein Fistula in Neurofibromatosis Type 1

Spontaneous cervical extradural pseudoaneurysms or arteriovenous fistulas (AVFs) are rare vascular diseases. We report a case of ruptured occipital artery (OA) pseudoaneurysm associated with occipital-internal jugular vein (IJV) fistula in neurofibromatosis type 1. Endovascular internal trapping via the OA was attempted; however, the distal entry of the OA could not be accessed because of the high shunt flow and tortuosity of the OA. The distal part of the OA was obliterated with coil via a transvenous approach through the IJV and pseudoaneurysm. The proximal entry of the OA was obliterated with coil and glue under proximal flow control with a balloon, and the fistula was successfully obliterated without placement of coils in the pseudoaneurysm. When ordinary internal trapping via a transarterial approach is not possible, the transvenous approach should be considered as an alternative for AVF associated with an aneurysmal component.

Bioinformatic Challenges in Clinical Diagnostic Application of Targeted Next Generation Sequencing: Experience from Pheochromocytoma

Background

Recent studies have demonstrated equal quality of targeted next generation sequencing (NGS) compared to Sanger Sequencing. Whereas these novel sequencing processes have a validated robust performance, choice of enrichment method and different available bioinformatic software as reliable analysis tool needs to be further investigated in a diagnostic setting.

Methods

DNA from 21 patients with genetic variants in SDHB, VHL, EPAS1, RET, (n=17) or clinical criteria of NF1 syndrome (n=4) were included. Targeted NGS was performed using Truseq custom amplicon enrichment sequenced on an Illumina MiSEQ instrument. Results were analysed in parallel using three different bioinformatics pipelines; (1) Commercially available MiSEQ Reporter, fully automatized and integrated software, (2) CLC Genomics Workbench, graphical interface based software, also commercially available, and ICP (3) an in-house scripted custom bioinformatic tool.

Results

A tenfold read coverage was achieved in between 95-98% of targeted bases. All workflows had alignment of reads to SDHA and NF1 pseudogenes. Compared to Sanger sequencing, variant calling revealed a sensitivity ranging from 83 to 100% and a specificity of 99.9-100%. Only MiSEQ reporter identified all pathogenic variants in both sequencing runs.

Conclusions

We conclude that targeted next generation sequencing have equal quality compared to Sanger sequencing. Enrichment specificity and the bioinformatic performance need to be carefully assessed in a diagnostic setting. As acceptable accuracy was noted for a fully automated bioinformatic workflow, we suggest that processing of NGS data could be performed without expert bioinformatics skills utilizing already existing commercially available bioinformatics tools.

18-fluorodeoxyglucose-positron emission tomography (FDG-PET) evaluation of nodular lesions in patients with Neurofibromatosis type 1 and plexiform neurofibromas (PN) or malignant peripheral nerve sheath tumors (MPNST)

BACKGROUND

Individuals with Neurofibromatosis type 1 (NF1) are at risk for developing malignant peripheral nerve sheath tumors (MPNST), which frequently arise in preexisting plexiform neurofibromas (PN). Magnetic resonance imaging (MRI) with volumetric analysis and 18-fluorodeoxyglucose-positron emission tomography (FDG-PET) were utilized to monitor symptomatic nodular lesions.

PROCEDURE

Patients with NF1 and PN on a NCI natural history trial were monitored for total body tumor volume (TTV) using volumetric MRI. FDG-PET was performed in individuals with a nodular well-demarcated lesion ≥3 cm if they were growing, painful, or there was a prior history of MPNST (target lesions). Asymptomatic nodular lesions were evaluated as non-target lesions.

RESULTS

Fifteen patients (8m, 7f) median age of 18.3 years (range, 10-45 years) had a single target and non-target (n = 46) nodular lesions identified on MRI. Target lesions arose within (n = 8) or outside (n = 3) a PN, and all but 1 had increased FDG uptake. FDG uptake was increased in non-target lesions but to a lesser degree. FDG uptake in the surrounding PN was low, similar to background activity. Pathologic evaluation performed in 11 patients demonstrated neurofibroma (n = 6), atypical neurofibroma (n = 2) and malignancy (n = 3).

CONCLUSIONS

Nodular target lesions identified on MRI in individuals with NF1 and PN demonstrate increased FDG uptake similar to MPNST, but may be benign on biopsy. Nodular target lesions may be at greater risk for malignant transformation, but their biologic and clinical behavior has not been well studied. Careful longitudinal evaluation will be required to better understand the malignant potential of these lesions.

Posterior vertebral column resection for the treatment of dystrophic kyphosis associated with type-1 neurofibromatosis: a case report and review of the literature

STUDY DESIGN

Case report.

OBJECTIVE

To describe the use of posterior-only vertebral column resection and postoperative traction for spinal deformity associated with type-1 neurofibromatosis (NF1).

SUMMARY OF BACKGROUND DATA

Vertebral deformity, namely, thoracic scoliosis, is the predominant orthopedic manifestation of NF1. Patients may present with debilitating pain and rarely, myelopathy. The commonly dystrophic nature of these deformities makes them particularly recalcitrant to surgical correction. Traditionally, circumferential arthrodesis via combined anterior and posterior approaches has been recommended.

METHODS

Clinical and radiographical case review.

RESULTS

A 14-year-old adolescent boy with NF1, severe cervicothoracic angular kyphosis, thoracic dislocation, and myelopathy presented status postmultiple anterior and posterior spinal fusions. The patient underwent posterior-only vertebral column resection after 6 weeks of halo-gravity traction. The surgery consisted of thoracic laminectomies, total corpectomies of T3 and T4, circumferential fusion, and posterior instrumentation from the occiput to T11. Autologous rib and iliac crest grafts were used as fusion substrate. Postoperatively, a halo vest was worn for 4 months to support the correction of his chin-on-chest deformity. The patient's neurological status returned to normal by 6 weeks postoperatively, and solid fusion was radiologically evident after 1 year.

CONCLUSION

We think that posterior-only vertebral column resection represents a safe and efficacious but technically challenging option for the treatment of angular kyphotic spinal deformity and associated neurological deficit in patients with NF1.

Recurrent retroperitoneal liposarcoma in a patient with neurofibromatosis type I

INTRODUCTION

Liposarcoma complicating neurofibromatosis is very rare. Only a few cases have been described until now. We present a case of recurrent dedifferentiated retroperitoneal liposarcoma in a patient with neurofibromatosis type I (NF-1).

CASE PRESENTATION

A 47-year-old Caucasian woman with NF-1 presented to the hospital initially complaining of left lumbar pain irradiating to the anterior thigh and knee. Physical examination showed atrophy of the lower extremities bilaterally and decreased motor strength on the left lower extremity. Radiological studies demonstrated an enhancing lesion in the left paraspinal region, suggesting malignancy. The patient underwent local resection of tumour with safety margins. Pathological examination was consistent with dedifferentiated liposarcoma (DDLS) with positivity for MDM2 and CDK4 markers. No evidence of metastasis was noted on the radiological studies. The final diagnosis was DDLS, high-grade (G3), pT2bN0M0, stage III. After 6 weeks post-tumour resection, the patient experienced recurrence of malignancy. Chemotherapy with cisplatin and doxorubicin was initiated in the patient.

CONCLUSIONS

Liposarcoma in the context of neurofibromatosis is very rare. To the best of our knowledge, only six cases have been reported until now in the literature. We are presenting this case to underline the possibility of recurrence in the case of retroperitoneal DDLSs despite local tumour resection. Also, although the role of chemotherapy is controversial we decided to start treatment with cisplatin and doxorubicin given the success of chemotherapy in similar case presentations.

The role of angiogenesis in the transformation of plexiform neurofibroma into malignant peripheral nerve sheath tumors in children with neurofibromatosis type 1

PURPOSE

The role of angiogenesis in the transformation of peripheral neurofibroma (PNF) to malignant peripheral nerve sheath tumor (MPNST) in neurofibromatosis type 1 (NF1) remains elusive and forms the objective of this study.

EXPERIMENTAL DESIGN

Archival tissue from 5 children with NF1 and PNF, who developed MPNST between the ages of 8 and 15 years were analyzed for differences in microvasculature. The role of proangiogenic growth factors such as Vascular Endothelial Growth Factor (VEGF), and its receptors Flk-1 and Flt-1, and vessel maturity, defined as von Willebrand factor (vWf), α-smooth muscle actin+ (SMA+), were evaluated by immuno-histochemistry.

RESULTS

A qualitative evaluation of the vasculature showed predominantly α-SMA+/vWf+ more stable vessels in PNF, and an irregular meshwork of α-SMA-/vWf+ endothelial cells structures in MPNST. In NF and PNF tumor cells were VEGF-, in contrast to VEGF+ tumor cells in MPNST. If present, the VEGF stain was confined mainly to the perivascular spaces in PNF, unlike the mainly stromal VEGF stain in MPNST. VEGF receptors also manifested a tumor stage-specific pattern. Flk-1 and Flt-1 were restricted to the mature, well-formed vasculature in PNF, but exhibited a diffuse pattern in MPNST.

CONCLUSION

Our study provides a rare opportunity to document consistent and histologically detectable differences in the vascular organization of PNF and MPNST. It permits a pair-wise evaluation of the malignant conversion of benign PNF into its malignant counterpart, in the same patients. The phenotypic variations and characteristics of the vessels in these tumors are consistent with the idea that a strong proangiogenic drive contributes to the progressive growth in MPNST.

Adjuvant chemotherapy in localized soft tissue sarcomas: still not proven

Soft tissue sarcoma is a rare and heterogeneous group of tumors in terms of histological subtypes, molecular alterations, clinical presentation, and prognosis. Yet, these tumors are most often treated similarly in the localized phase. The standard treatment of these patients requires multidisciplinary management, in particular, careful diagnostic procedures and surgery by an expert physician, preceded or followed by external radiotherapy. The utility of adjuvant chemotherapy has been explored in 14 trials comparing adjuvant chemotherapy with no treatment. Several trials reported a lower risk for local relapse and lower risk for metastatic relapse, but only a few small trials reported longer overall survival. A meta-analysis of all trials failed to demonstrate a significant difference in the relapse-free survival (RFS) or overall survival rates. Two additional trials, reported afterward, presented conflicting results, with a significant benefit in terms of the RFS rate for the trial of the Italian Sarcoma Group, but no difference in the RFS or overall survival rate in the most recent European Organization for Research and Treatment of Cancer trial. We conclude that adjuvant chemotherapy has not been proven to improve the outcome of an unselected population of patients. Several hypotheses are proposed to account for this observation.

Spontaneous regression of low-grade gliomas in pediatric patients without neurofibromatosis

OBJECTIVE

Pediatric low-grade gliomas comprise a diverse range of central nervous system tumors, sharing the usual course of a slow progression in growth. In individual cases however, the natural history can be variable, and rarely spontaneous regression has been described. This paper describes factors associated with spontaneous regression.

METHODS

A literature review was performed to identify factors associated with spontaneous regression. A unique case is described to contribute to the findings.

RESULTS

Low-grade gliomas occurring in association with neurofibromatosis are more likely to spontaneously regress. Only 14 cases of spontaneous regression of low-grade gliomas in patients without neurofibromatosis have been described, and of these, the vast majority regress in association with optic chiasm gliomas. We describe the first documented case of spontaneous regression of a temporal lobe pilocytic astrocytoma in a patient without neurofibromatosis.

CONCLUSION

Spontaneous regression of low-grade gliomas can occur for tumors in a diversity of anatomical locations, at varying ages and in both sexes. This may have implications for management. As such, spontaneous tumor regression is an important outcome to be considered for pediatric low-grade gliomas and pilocytic astrocytomas.

Sarcomas in children with neurofibromatosis type 1-poor prognosis despite aggressive combined therapy in four patients treated in a single oncological institution

OBJECTS

Patients with neurofibromatosis type 1 (NF1) are predisposed to developing soft tissue sarcomas (STS).

MATERIALS AND METHODS

We report on four cases of STS diagnosed in locally advanced, unresectable stages in children with NF1 (three girls, one boy; age = 8 months-14 years). All patients received protocols for STS: Cooperative Weichteilsarkomstudie 91, 96 and 2002. One patient with limb rhabdomyosarcoma entered complete remission but developed late metastatic relapse and died of progression despite complete excision and autologous bone marrow transplantation. The other patient with bladder rhabdomyosarcoma died of neutropenia-related sepsis without remission. Patients with malignant peripheral nerve sheet tumour and malignant triton tumour located in the pelvis did not respond to therapy. One of them died of disease progression, while the other is disease-free 6 years post-therapy after mutilating tumour resection.

CONCLUSION

STS in NF1 seem to display poor prognosis in spite of combined therapy; thus, children with NF1 should remain under detailed control of the oncologist.

Treatments for astrocytic tumors in children: current and emerging strategies

Strategies for the treatment of childhood cancer have changed considerably during the last 50 years and have led to dramatic improvements in long-term survival. Despite these accomplishments, CNS tumors remain the leading cause of death in pediatric oncology. Astrocytic tumors form the most common histologic group among childhood brain tumors. They are a heterogeneous group that from a practical therapeutic point of view can be subdivided into low-grade astrocytomas (LGA), optic pathway gliomas (OPG), high-grade astrocytomas (HGA), and brainstem gliomas (BSG). This article focuses on the practical application of treatments that lead to long-term survival, improved quality of life, and reduced long-term complications. Improvement in therapy has led to better outcomes for patients with LGA and OPG. Careful follow-up without any treatment is indicated for a small percentage of patients diagnosed with LGA with an indolent course including children with neurofibromatosis type 1 (NF1). Surgery is the main recommended treatment for children with resectable LGA. Radiation therapy is generally recommended for children with progressive LGA, or after failure of chemotherapy, accomplishing tumor control at 10 years in over 60% of patients. Cytotoxic chemotherapy is usually reserved for children who have had treatment failure with surgery and radiation therapy. It is also offered for children who are too young to be treated with radiation or to defer or avoid radiotherapy. Carboplatin and vincristine achieve 5% complete and 28% partial responses but the use of vincristine is criticized due to poor penetration of the CNS. A regimen of tioguanine, procarbazine, mitolactol, lomustine, and vincristine is frequently administered as an alternative to carboplatin and vincristine in LGA. The introduction of temozolomide has allowed better responses, including a 24% complete response rate compared with 0-5% complete response rates with the previous regimens. OPG are usually histologically LGA, and are treated with similar chemotherapy regimens. OPG is the most common type of brain tumor associated with NF1. Tumor growth in some of these patients is slow with no treatment recommended for an extended period of time. The prognosis for children with the remaining types of astrocytomas remains poor. Surgical resection is typically the first step in the treatment of HGA followed in older children by radiation therapy. The data regarding chemotherapy are mixed. Combination chemotherapy before or after radiation, including cisplatin, carmustine, cyclophosphamide, and vincristine or carboplatin, ifosfamide, cyclophosphamide, and etoposide has provided disappointing results. Clinical trials with temozolomide and agents directed against single targets have not shown substantially better results, but it is hoped that currently conducted studies will provide better outcomes. Diffuse intrinsic BSG are among the most difficult-to-treat brain tumors. Surgical treatment is not recommended for diffuse intrinsic BSG and standard radiation therapy is typically given in children aged >3 years. None of the numerous chemotherapy regimens, including temozolomide, has provided a significant response rate or an improvement in survival. It is expected that newer agents affecting multiple targets such as AEE-788 and antineoplastons, and combinations of single-targeted agents with chemotherapy will provide better results. Careful evaluation of histology, location of the tumor, patient age, and consideration of treatment-related morbidity play an important part in selecting between clinical observation, surgery, radiation, chemotherapy, or investigational agents. The goals of treatment for astrocytic tumors should extend well beyond objective responses and increased survival. Improvement of quality of life is an equally important objective of treatment. Radiation therapy and chemotherapy result in serious late toxicities.

Incidence patterns of soft tissue sarcomas, regardless of primary site, in the surveillance, epidemiology and end results program, 1978-2001: An analysis of 26,758 cases

Soft tissue sarcomas (STS) are a heterogeneous group of uncommon tumors that show a broad range of differentiation that may reflect etiologic distinction. Routine tabulations of STS are not morphology-specific. Further, the lack of inclusion of sarcomas arising in all organs in most standard evaluations underestimates the true rates. We analyzed the 1978-2001 Surveillance, Epidemiology and End Results program incidence rates of STS regardless of primary site, except bones and joints, using the 2002 criteria of the WHO classification. There were 26,758 cases available for analysis. Leiomyosarcomas accounted for 23.9%, malignant fibrous histiocytomas 17.1%, liposarcomas 11.5%, dermatofibrosarcomas 10.5%, rhabdomyosarcomas 4.6% and angiosarcomas 4.1%. Almost half (47.9%) of the sarcomas arose in the soft tissues, 14.0% in the skin and 7.0% in the uterus. Overall, incidence rates were highest among black women (6.26/100,000 woman-years) and the lowest among white women (4.60/100,000). Age-adjusted rates increased at 1.2% and 0.8% per year among white males and females, respectively, both trends statistically significant, while rates among blacks declined slightly. About 40% of leiomyosarcomas among women were uterine in origin, with a black/white rate ratio of 1.7. This rate ratio increased to 2.0 when we accounted for the lower prevalence of intact uteri among black compared to white women. Total STS rates rose exponentially with age. Rates for both uterine leiomyosarcoma and dermatofibrosarcoma increased rapidly during the childbearing years, peaking at about age 40 and 50, respectively. Incidence patterns of STS varied markedly by histologic type, supporting the notion that these tumors may be etiologically distinct.

State of the art chemotherapeutic management of pediatric brain tumors

CNS tumors are the most common solid tumor of childhood. This article will review current treatments for pediatric brain tumors; low-grade gliomas, high-grade gliomas, medulloblastomas and ependymomas. It will also highlight the treatments that are used for brain tumors in very young children and in children with recurrent brain tumors. The management of recurrent pediatric brain tumors unresponsive to standard therapy will be discussed. The agents used in this setting are mainly biological modifiers, which attempt to provide molecularly targeted therapy. Future directions of therapy for pediatric brain tumors are described. Future treatment paradigms will need to consider examining the use of multiple biological modifiers. Similarly, these agents will need to be examined in combination with cytotoxic chemotherapy. Finally, the future direction of pediatric neuro-oncology and the focus of the field as it battles pediatric brain tumors is discussed.

Spinal deformity in neurofibromatosis type-1: diagnosis and treatment

Spinal deformity is the commonest orthopaedic manifestation in neurofibromatosis type-1 and is categorized into dystrophic and non-dystrophic types. Management should be based on a meticulous assessment of the spine with plain radiography and magnetic resonance imaging (MRI) to rule out the presence of dysplastic features that will determine prognosis and surgical planning. MRI of the whole spine should also be routinely obtained to reveal undetected intraspinal lesions that could threaten scheduled surgical interventions. Non-dystrophic curvatures can be treated with similar decision-making criteria to those applied in the management of idiopathic scoliosis. However, close observation is necessary due to the possibility of modulation with further growth and due to the increased reported risk of pseudarthrosis after spinal fusion. The relentless progressive nature of dystrophic curves necessitates aggressive operative treatment, which often has a significant toll on the quality of life of affected patients through their early childhood. Bracing of dystrophic curves has been unsuccessful. Combined anterior/posterior spinal arthrodesis including the entire structural component of the deformity is indicated in most cases, particularly in the presence of associated sagittal imbalance. This should be performed using abundant autologous bone graft and segmental posterior instrumentation to minimize the risk of non-union and recurrence of the deformity.

Pigment cell-related manifestations in neurofibromatosis type 1: an overview

Neurofibromatosis type 1 (NF1) is an autosomal dominant neurocutaneous disorder, affecting approximately 1 in 3500 individuals. The most commonly seen tumors in NF1 patients are the (sub)cutaneous neurofibromas. However, individuals with NF1 typically present in childhood with well-defined pigmentary defects, including cafe-au-lait macules (CALMs), intertriginous freckling and iris Lisch nodules. NF1 is considered a neurocristopathy, primarily affecting tissues derived from the neural crest. Since the pigment producing melanocyte originates in the neural crest, the presence of (hyper)pigmentary lesions in the NF1 phenotype because of changes in melanocyte cell growth and differentiation is to be expected. We want to discuss the pigmentary cutaneous manifestations of NF1 represented by CALMs and intertriginous freckles and the pigmentary non-cutaneous manifestations represented by iris Lisch nodules. Several hypotheses have been suggested in explaining the poorly understood etiopathogenesis of CALMs. Whether other pigmentary manifestations might share similar etiopathogenic mechanisms remains obscure. Additional attention will be drawn to a readily seen phenomenon in NF1: hyperpigmentation overlying (plexiform) neurofibromas, which could suggest common etiopathogenetic-environmental cues or mechanisms underlying CALMs and neurofibromas. Finally, we want to address the relationship between malignant melanoma and NF1.

Somatic Mitochondrial DNA Mutations in Neurofibromatosis Type 1-Associated Tumors

Neurofibromatosis type 1 is an autosomal dominantly inherited disease predisposing to a multitude of tumors, most characteristically benign plexiform neurofibromas and diffuse cutaneous neurofibromas. We investigated the presence and distribution of somatic mitochondrial DNA (mtDNA) mutations in neurofibromas and in nontumor tissue of neurofibromatosis type 1 patients. MtDNA alterations in the entire mitochondrial genome were analyzed by temporal temperature gradient gel electrophoresis followed by DNA sequencing. Somatic mtDNA mutations in tumors were found in 7 of 19 individuals with cutaneous neurofibromas and in 9 of 18 patients with plexiform neurofibromas. A total of 34 somatic mtDNA mutations were found. All mutations were located in the displacement loop region of the mitochondrial genome. Several plexiform neurofibromas from individual patients had multiple homoplasmic mtDNA mutations. In cutaneous neurofibromas, the same mtDNA mutations were always present in tumors from different locations of the same individual. An increase in the proportion of the mutant mtDNA was always found in the neurofibromas when compared with nontumor tissues. The somatic mtDNA mutations were present in the Schwann cells of the analyzed multiple cutaneous neurofibromas of the same individual. The observed dominance of a single mtDNA mutation in multiple cutaneous neurofibromas of individual patients indicates a common tumor cell ancestry and suggests a replicative advantage rather than random segregation for cells carrying these mutated mitochondria.

Activation of the protein kinase A pathway in human endometrial stromal cells reveals sequential categorical gene regulation

Decidualization of endometrial stromal cells is a prerequisite for human implantation and occurs in vivo in response to progesterone and involves activation of the protein kinase A (PKA) pathway. The objective of this study was to determine the molecular signatures and patterns of gene expression during stimulation of this pathway with an analog of cAMP. Endometrial stromal cells from two subjects were treated with or without 8-Br-cAMP (1 mM) for 0, 2, 12, 24, 36, and 48 h and were processed for microarray analysis, screening for 12,686 genes and ESTs. Most abundantly upregulated genes included neuropeptides, immune genes, IGF family members, cell cycle regulators, extracellular matrix proteases, cholesterol trafficking, cell growth and differentiation, hormone signaling, and signal transduction. Most abundantly downregulated genes included activator of NF-kappaB, actin/tropomyosin/calmodulin binding protein, cyclin B, IGFBP-5, alpha1 type XVI collagen, lipocortin III, l-kynurenine hydrolase, frizzle-related protein, and cyclin E2. RT-PCR validated upregulation of IGFBP-1, preprosomatostatin, and IL-11, and Northern analysis validated their kinetic upregulation. RT-PCR confirmed downregulation of IGFBP-5, cyclin B, and TIL-4. K-means analysis revealed four major patterns of up- and downregulated genes, and genes within each ontological group were categorized into these four kinetic patterns. Within each ontological group different patterns of temporal gene expression were observed, indicating that even genes within one functional category are regulated differently during activation of the PKA pathway in human endometrial stromal cells. Overall, the data demonstrate kinetic reprogramming of genes within specific functional groups and changes in genes associated with nucleic acid binding, cell proliferation, decreased G protein signaling, increased STAT pathway signaling, structural proteins, cellular differentiation, and secretory processes. These changes are consistent with cAMP modulating early events (0-6 h) primarily involving cell cycle regulation, subsequent events (12-24 h) involving cellular differentiation (including changes in morphology and secretory phenotype), and late events (24-48 h) mediating more specialized function, including immune modulators, in the human endometrial stromal cell.

Genetics of Neurofibromatosis 1-Associated Peripheral Nerve Sheath Tumors

Neurofibromatosis 1, an inherited disorder that affects 1/3500 individuals worldwide, predisposes to the development of benign and malignant peripheral nerve sheath tumors. The disorder results from inactivation of one of the NFI genes. The second NFI gene is typically inactivated in Schwann cells during tumor formation. This article reviews the different types of genetic alterations in NFI in both constitutional and tumor tissues and genetic alterations of other genes that may affect tumorigenesis. These studies have provided insight into the genetic basis of both the variable expression of the disorder and of benign and malignant peripheral nerve sheath tumorigenesis.