Guidelines for the diagnosis and management of cystathionine beta-synthase deficiency.

Cystathionine beta-synthase (CBS) deficiency is a rare inherited disorder in the methionine catabolic pathway, in which the impaired synthesis of cystathionine leads to accumulation of homocysteine. Patients can present to many different specialists and diagnosis is often delayed. Severely affected patients usually present in childhood with ectopia lentis, learning difficulties and skeletal abnormalities. These patients generally require treatment with a low-methionine diet and/or betaine. In contrast, mildly affected patients are likely to present as adults with thromboembolism and to respond to treatment with pyridoxine. In this article, we present recommendations for the diagnosis and management of CBS deficiency, based on a systematic review of the literature. Unfortunately, the quality of the evidence is poor, as it often is for rare diseases. We strongly recommend measuring the plasma total homocysteine concentrations in any patient whose clinical features suggest the diagnosis. Our recommendations may help to standardise testing for pyridoxine responsiveness. Current evidence suggests that patients are unlikely to develop complications if the plasma total homocysteine concentration is maintained below 120 µmol/L. Nevertheless, we recommend keeping the concentration below 100 µmol/L because levels fluctuate and the complications associated with high levels are so serious.

A review of the symptomatic management of malignant gliomas in adults.

Malignant brain tumors are aggressive tumors with a very poor prognosis. Survival is on average 12 to 18 months. Patients with malignant gliomas are subject to multiple medical problems that can significantly impact their overall survival and quality of life, including seizures, cerebral edema, venous thromboembolism, cognitive and psychiatric disorders, and side effects of chemotherapy, such as nausea, vomiting, myelosuppression, constipation, and diarrhea. This article examines the evidence for managing many of these issues to reduce symptoms and improve quality of life.

Central nervous system cancers.

Primary and metastatic tumors of the central nervous system are a heterogeneous group of neoplasms with varied outcomes and management strategies. Recently, improved survival observed in 2 randomized clinical trials established combined chemotherapy and radiation as the new standard for treating patients with pure or mixed anaplastic oligodendroglioma harboring the 1p/19q codeletion. For metastatic disease, increasing evidence supports the efficacy of stereotactic radiosurgery in treating patients with multiple metastatic lesions but low overall tumor volume. These guidelines provide recommendations on the diagnosis and management of this group of diseases based on clinical evidence and panel consensus. This version includes expert advice on the management of low-grade infiltrative astrocytomas, oligodendrogliomas, anaplastic gliomas, glioblastomas, medulloblastomas, supratentorial primitive neuroectodermal tumors, and brain metastases. The full online version, available at NCCN. org, contains recommendations on additional subtypes.

Alliance A071401: Phase II Trial of Focal Adhesion Kinase Inhibition in Meningiomas With Somatic NF2 Mutations.

PURPOSE: Patients with progressive or recurrent meningiomas have limited systemic therapy options. Focal adhesion kinase (FAK) inhibition has a synthetic lethal relationship with NF2 loss. Given the predominance of NF2 mutations in meningiomas, we evaluated the efficacy of GSK2256098, a FAK inhibitor, as part of the first genomically driven phase II study in recurrent or progressive grade 1-3 meningiomas. PATIENTS AND METHODS: Eligible patients whose tumors screened positively for NF2 mutations were treated with GSK2256098, 750 mg orally twice daily, until progressive disease. Efficacy was evaluated using two coprimary end points: progression-free survival at 6 months (PFS6) and response rate by Macdonald criteria, where PFS6 was evaluated separately within grade-based subgroups: grade 1 versus 2/3 meningiomas. Per study design, the FAK inhibitor would be considered promising in this patient population if either end point met the corresponding decision criteria for efficacy. RESULTS: Of 322 patients screened for all mutation cohorts of the study, 36 eligible and evaluable patients with NF2 mutations were enrolled and treated: 12 grade 1 and 24 grade 2/3 patients. Across all grades, one patient had a partial response and 24 had stable disease as their best response to treatment. In grade 1 patients, the observed PFS6 rate was 83% (10/12 patients; 95% CI, 52 to 98). In grade 2/3 patients, the observed PFS6 rate was 33% (8/24 patients; 95% CI, 16 to 55). The study met the PFS6 efficacy end point both for the grade 1 and the grade 2/3 cohorts. Treatment was well tolerated; seven patients had a maximum grade 3 adverse event that was at least possibly related to treatment with no grade 4 or 5 events. CONCLUSION: GSK2256098 was well tolerated and resulted in an improved PFS6 rate in patients with recurrent or progressive NF2-mutated meningiomas, compared with historical controls. The criteria for promising activity were met, and FAK inhibition warrants further evaluation for this patient population.

TIF1 activates the intra-S-phase checkpoint response in the diploid micronucleus and amitotic polyploid macronucleus of Tetrahymena.

The ribosomal DNA origin binding protein Tif1p regulates the timing of rDNA replication and is required globally for proper S-phase progression and division of the Tetrahymena thermophila macronucleus. Here, we show that Tif1p safeguards chromosomes from DNA damage in the mitotic micronucleus and amitotic macronucleus. TIF1p localization is dynamically regulated as it moves into the micro- and macronucleus during the respective S phases. TIF1 disruption mutants are hypersensitive to hydroxyurea and methylmethanesulfonate, inducers of DNA damage and intra-S-phase checkpoint arrest in all examined eukaryotes. TIF1 mutants incur double-strand breaks in the absence of exogenous genotoxic stress, destabilizing all five micronuclear chromosomes. Wild-type Tetrahymena elicits an intra-S-phase checkpoint response that is induced by hydroxyurea and suppressed by caffeine, an inhibitor of the apical checkpoint kinase ATR/MEC1. In contrast, hydroxyurea-challenged TIF1 mutants fail to arrest in S phase or exhibit caffeine-sensitive Rad51 overexpression, indicating the involvement of TIF1 in checkpoint activation. Although aberrant micro- and macronuclear division occurs in TIF1 mutants and caffeine-treated wild-type cells, TIF1p bears no similarity to ATR or its substrates. We propose that TIF1 and ATR function in the same epistatic pathway to regulate checkpoint responses in the diploid mitotic micronucleus and polyploid amitotic macronucleus.

TIF1 Represses rDNA replication initiation, but promotes normal S phase progression and chromosome transmission in Tetrahymena.

The non-ORC protein, TIF1, recognizes sequences in the Tetrahymena thermophila ribosomal DNA (rDNA) minichromosome that are required for origin activation. We show here that TIF1 represses rDNA origin firing, but is required for proper macronuclear S phase progression and division. TIF1 mutants exhibit an elongated macronuclear S phase and diminished rate of DNA replication. Despite this, replication of the rDNA minichromosome initiates precociously. Because rDNA copy number is unaffected in the polyploid macronucleus, mechanisms that prevent reinitiation appear intact. Although mutants exit macronuclear S with a wild-type DNA content, division of the amitotic macronucleus is both delayed and abnormal. Nuclear defects are also observed in the diploid mitotic micronucleus, as TIF1 mutants lose a significant fraction of their micronuclear DNA. Hence, TIF1 is required for the propagation and subsequent transmission of germline chromosomes. The broad phenotypes associated with a TIF1-deficiency suggest that this origin binding protein is required globally for the proper execution and/or monitoring of key chromosomal events during S phase and possibly at later stages of the cell cycle. We propose that micro- and macronuclear defects result from exiting the respective nuclear S phases with physically compromised chromosomes.

Bony metastases of anaplastic oligodendroglioma respond to temozolomide.

BACKGROUND: Fewer than 30 cases of oligodendroglioma or anaplastic oligodendroglioma metastatic to bone are reported in the literature. Prolonged survival even with therapy is uncommon. METHODS: We report a case of anaplastic oligodendroglioma metastatic to bone with a dramatic and durable response to temozolomide therapy. A retrospective case review, molecular analysis, and literature search were performed. RESULTS: The patient presented with a right frontal mass in 1990. Progression led to resection of the lesion in 1995. Histology revealed an anaplastic oligodendroglioma and the tumour was found to have allelic loss of heterozygosity (LOH) of chromosome 1p (1p-). He received standard radiation therapy. In 2000 he developed hip and pelvic pain. A bone scan showed multiple skeletal lesions. Magnetic resonance imaging of the brain showed stability of intracranial disease. Resection of one lesion found metastatic anaplastic oligodendroglioma with identical morphology to the patient's original tumour, including glial fibrillary acidic protein expression. The patient was started on standard temozolomide chemotherapy and celecoxib with prompt pain relief, and rapid normalization of serum alkaline phosphatase. He received a total of 12 cycles of combined therapy with no toxicity and no evidence of progression until increasing pain marked disease recurrence. The patient underwent palliative chemo- and radiation therapy but eventually succumbed. DISCUSSION: Loss of heterozygosity 1p- is associated with prolonged survival in anaplastic oligodendroglioma and may increase the cumulative risk for development of systemic metastases. We speculate that metastases from oligodendroglioma harbouring loss of heterozygosity at chromosome 1p- retain the chemosensitivity of the initial lesion.

Peripheral primitive neuroectodermal tumor of the dura in a 51-year-old woman following intensive treatment for breast cancer.

PATIENT: Female, 51. FINAL DIAGNOSIS: Ewing sarcoma. SYMPTOMS: Visual disturbances. MEDICATION: -. CLINICAL PROCEDURE: -. SPECIALTY: Oncology. OBJECTIVE: Rare disease. BACKGROUND: Primitive neuroectodermal tumor/Ewing sarcoma (PNET/EWS) is a round blue cell sarcoma that shows varying degrees of neuroectodermal differentiation. PNET/EWS as a primary intracranial tumor is extremely uncommon. CASE REPORT: We report a unique case of peripheral PNET presenting as an intracranial mass in an adult following chemotherapy and radiotherapy for a solid tumor. A 51-year-old woman with previously treated left breast cancer was evaluated for a newly developed brain mass. She underwent craniotomy with resection. Surgical pathology was consistent with a peripheral PNET/EWS with Ewing sarcoma gene translocation. She was treated appropriately with vincristine, cyclophosphamide, and doxorubicin (later dactinomycin) alternating with ifosfamide and etoposide. CONCLUSIONS: Although development of PNET/EWS presenting along the CNS is exceedingly rare in adults, establishing the proper diagnosis of this "small blue cell tumor" is critical. The further distinction between central PNET and peripheral PNET can greatly impact both prognosis and treatment. Our case also highlights the importance of considering the impact of prior intensive therapies, including radiation and chemotherapy, on predisposing to future PNET/EWS.

Temozolomide rechallenge in recurrent malignant glioma by using a continuous temozolomide schedule: the "rescue" approach.

BACKGROUND: Despite advances in first-line therapy, there are few data on treatment of glioblastoma multiforme (GBM) at recurrence. Temozolomide (TMZ) is well tolerated and may have activity despite prior TMZ exposure if novel dose schedules are used. METHODS: The authors reviewed their experience with a continuous TMZ schedule (50 mg/m(2) daily), given at progression after conventional 5-day TMZ. Patients were reported in 3 groups: 1) GBM after progression on conventional TMZ; 2) GBM at first recurrence after completion of standard concomitant and adjuvant TMZ; and 3) patients with other anaplastic gliomas at second relapse on conventional TMZ. RESULTS: In Group 1, 21 patients with a median age of 54 years (range, 33 years-68 years) received a median of 3 cycles (range, 2-12 cycles) of continuous TMZ at 50 mg/m(2). Overall clinical benefit (complete response, partial response, and stable disease) was 47%, with 6-month progression-free survival (PFS) of 17%. In Group 2, 14 patients with GBM, median age 52 years (range, 38 years-62 years) received continuous TMZ at progression after initial TMZ/radiotherapy (RT) and adjuvant TMZ. The median interval after adjuvant TMZ was 3 months (range, 2 months-10 months). A median of 5 cycles of TMZ was given, and 6-month PFS was 57%. In Group 3, 14 patients with a median age of 49 years (range, 34 years-56 years) received continuous TMZ; 2 partial responses and 6 with stable disease were seen, with a 6-month PFS of 42%. Toxicities were mild and well tolerated; lymphopenia was common but no serious opportunistic infections were identified. CONCLUSIONS: Although retrospective, our results demonstrate that continuous daily administration of TMZ is an active regimen despite prior TMZ therapy. The excellent tolerability of this regimen may allow future combination with other alkylating agents or with novel therapies.