Advanced ADC Histogram, Perfusion, and Permeability Metrics Show an Association with Survival and Pseudoprogression in Newly Diagnosed Diffuse Intrinsic Pontine Glioma: A Report from the Pediatric Brain Tumor Consortium.

BACKGROUND AND PURPOSE: Diffuse intrinsic pontine glioma is a lethal childhood brain cancer with dismal prognosis and MR imaging is the primary methodology used for diagnosis and monitoring. Our aim was to determine whether advanced diffusion, perfusion, and permeability MR imaging metrics predict survival and pseudoprogression in children with newly diagnosed diffuse intrinsic pontine glioma. MATERIALS AND METHODS: A clinical trial using the poly (adenosine diphosphate ribose) polymerase (PARP) inhibitor veliparib concurrently with radiation therapy, followed by maintenance therapy with veliparib + temozolomide, in children with diffuse intrinsic pontine glioma was conducted by the Pediatric Brain Tumor Consortium. Standard MR imaging, DWI, dynamic contrast-enhanced perfusion, and DSC perfusion were performed at baseline and approximately every 2 months throughout treatment. ADC histogram metrics of T2-weighted FLAIR and enhancing tumor volume, dynamic contrast-enhanced permeability metrics for enhancing tumors, and tumor relative CBV from DSC perfusion MR imaging were calculated. Baseline values, post-radiation therapy changes, and longitudinal trends for all metrics were evaluated for associations with survival and pseudoprogression. RESULTS: Fifty children were evaluable for survival analyses. Higher baseline relative CBV was associated with shorter progression-free survival (P = .02, Q = 0.089) and overall survival (P = .006, Q = 0.055). Associations of higher baseline mean transfer constant from the blood plasma into the extravascular extracellular space with shorter progression-free survival (P = .03, Q = 0.105) and overall survival (P = .03, Q = 0.102) trended toward significance. An increase in relative CBV with time was associated with shorter progression-free survival (P < .001, Q < 0.001) and overall survival (P = .004, Q = 0.043). Associations of longitudinal mean extravascular extracellular volume fraction with progression-free survival (P = .03, Q = 0.104) and overall survival (P = .03, Q = 0.105) and maximum transfer constant from the blood plasma into the extravascular extracellular space with progression-free survival (P = .03, Q = 0.102) trended toward significance. Greater increases with time were associated with worse outcomes. True radiologic progression showed greater post-radiation therapy decreases in mode_ADC_FLAIR compared with pseudoprogression (means, -268.15 versus -26.11, P = .01.) CONCLUSIONS: ADC histogram, perfusion, and permeability MR imaging metrics in diffuse intrinsic pontine glioma are useful in predicting survival and pseudoprogression.

MRI Features of Histologically Diagnosed Supratentorial Primitive Neuroectodermal Tumors and Pineoblastomas in Correlation with Molecular Diagnoses and Outcomes: A Report from the Children's Oncology Group ACNS0332 Trial.

BACKGROUND AND PURPOSE: Supratentorial primitive neuroectodermal tumors and pineoblastomas have traditionally been grouped together for treatment purposes. Molecular profiling of these tumors has revealed a number of distinct entities and has led to the term "CNS-primitive neuroectodermal tumors" being removed from the 2016 World Health Organization classification. The purpose of this study was to describe the MR imaging findings of histologically diagnosed primitive neuroectodermal tumors and pineoblastomas and correlate them with molecular diagnoses and outcomes. MATERIALS AND METHODS: Histologically diagnosed primitive neuroectodermal tumors and pineoblastomas were enrolled in this Children's Oncology Group Phase III trial, and molecular classification was retrospectively completed using DNA methylation profiling. MR imaging features were systematically studied and correlated with molecular diagnoses and survival. RESULTS: Of the 85 patients enrolled, 56 met the inclusion criteria, in whom 28 tumors were in pineal and 28 in nonpineal locations. Methylation profiling revealed a variety of diagnoses, including pineoblastomas (n = 27), high-grade gliomas (n = 17), embryonal tumors (n = 7), atypical teratoid/rhabdoid tumors (n = 3), and ependymomas (n = 2). Thus, 39% overall and 71% of nonpineal tumor diagnoses were discrepant with histopathology. Tumor location, size, margins, and edema were predictors of embryonal-versus-nonembryonal tumors. Larger size and ill-defined margins correlated with poor event-free survival, while metastatic disease by MR imaging did not. CONCLUSIONS: In nonpineal locations, only a minority of histologically diagnosed primitive neuroectodermal tumors are embryonal tumors; therefore, high-grade glioma or ependymoma should be high on the radiographic differential. An understanding of molecularly defined tumor entities and their relative frequencies and locations will help the radiologist make more accurate predictions of the tumor types.

Recurrent osteosarcoma with a single pulmonary metastasis: a multi-institutional review.

BACKGROUND: Late relapse and solitary lesion are positive prognostic factors in recurrent osteosarcoma. METHODS: We reviewed the records of 39 patients treated at three major centres for recurrent osteosarcoma with a single pulmonary metastasis more than 1 year after diagnosis. We analysed their outcomes with respect to clinical factors and treatment with chemotherapy. RESULTS: Median age at diagnosis was 14.6 years. Relapse occurred at a median of 2.5 years (range, 1.2-8.2 years) after initial diagnosis. At relapse, all patients were treated by metastasectomy; 12 (31%) patients also received chemotherapy. There was no difference in time to recurrence or nodule size between the patients who received or did not receive chemotherapy at relapse. Sixteen patients had no subsequent recurrence, 13 of whom survive without evidence of disease. The 5-year and 10-year estimates of post-relapse event-free survival (PREFS) were 33.0±7.5% and 33.0±9.6%, respectively, and of post-relapse survival (PRS) 56.8±8.6% and 53.0±11.0%, respectively. There was a trend for nodules <1.5 cm to correlate positively with PREFS (P=0.070) but not PRS (P=0.49). Chemotherapy at first relapse was not associated with PREFS or PRS. CONCLUSION: Approximately half of the patients with recurrent osteosarcoma presenting as a single pulmonary metastasis more than 1 year after diagnosis were long-term survivors. Metastasectomy was the primary treatment; chemotherapy did not add benefit.

Prognostic factors for local and distant control in Ewing sarcoma family of tumors.

BACKGROUND: Advances in the treatment of Ewing sarcoma family of tumors (ESFT) are the result of improvements in systemic and local therapies. The individual contributions of each treatment component cannot be analyzed separately; improvements in local and systemic control can influence each other. PATIENTS AND METHODS: We reviewed the records of 220 patients treated on institutional protocols from 1979 to 2004. Factors predictive of local and distant recurrence were analyzed. RESULTS: The median age at diagnosis was 13.7 years. Ninety-five patients relapsed at a median of 1.6 years. The 5-year overall survival estimate was 63.5% +/- 3.5%. The estimated 5-year cumulative incidence (CI) of local failure was 25.1% +/- 3.0%. Local failure was associated with treatment era (P < 0.001), tumor size (P = 0.037) and type of local control (P = 0.021). Systemic treatment intensification improved local control. The estimated 5-year CI of distant recurrence was 22.5% +/- 2.9%. Patients with localized disease (P < 0.001), smaller tumors (P = 0.018) and those who received surgery +/- radiation for local control (P = 0.023) had lower CI of distant failure. CONCLUSIONS: Successful treatment of ESFT requires optimal systemic and local therapy. Both treatment modalities are intertwined and the control of both local and distant disease is the result of the combined approach.

STAT3 is activated in a subset of the Ewing sarcoma family of tumours.

STAT3 is an oncogene that regulates critical cellular processes and whose constitutive activation has been demonstrated to correlate with biological and clinical features in many types of human malignancy. In this study, STAT3 activation was assessed in the Ewing sarcoma family of tumours (ESFT), which is characterized by fusion of the EWS gene with one of several Ets transcription factors, most commonly EWS-FLI1. STAT3 activation was assessed by immunohistochemistry using a monoclonal antibody specific for tyrosine(705)-phosphorylated STAT3 (pSTAT3(tyr705)) and a tissue microarray containing 49 paraffin-embedded ESFT tumours with known EWS translocations. Twenty-five (51%) tumours were pSTAT3(tyr705)-positive, as defined by more than 10% tumour cell immunostaining. STAT3 activation correlated with tumour site at presentation, with pSTAT3(tyr705)-negative ESFT involving axial sites predominantly (p = 0.008). Notably, among 31 patients who presented with localized disease, high-level STAT3 activation correlated with better overall survival (p = 0.02). STAT3 activation was not directly related to EWS-FLI1 expression, since EWS-FLI1 transfection did not result in STAT3 activation. Furthermore, detailed molecular analysis indicated that STAT3 activation may be seen with EWS-FLI1 or EWS-ERG and appears to be independent of EWS-FLI1 fusion type. In conclusion, STAT3 activation is present in approximately half of ESFT and correlates with clinical features. The role of STAT3 activation in ESFT pathogenesis seems to be independent of the type of EWS/Ets translocation.

Tumor size as a predictor of outcome in pediatric non-metastatic osteosarcoma of the extremity.

BACKGROUND: Better predictors of outcome would allow improved risk-adapted therapy for pediatric nonmetastatic osteosarcoma of the extremity. We investigated the predictive value of MR imaging-based measures of absolute and relative tumor size and volume at the time of diagnosis. We also assessed the relation of tumor size to age and histologic response. METHODS: We retrospectively abstracted demographic, treatment history, and outcome information of patients treated on a single institutional protocol. A single pediatric oncologic radiologist manually measured each primary lesion and the affected native bone in three dimensions on MR images obtained at the time of diagnosis. Eight parameters of tumor size were analyzed for their value in predicting overall survival (OS) and event-free survival (EFS). RESULTS: The median age of the 42 patients was 13.5 years (range: 5.9-18.7 years); 50% were female and 74% were Caucasian. Absolute tumor volume was an important predictor of OS (P < 0.05); absolute tumor depth (analyzed as a continuous variable) was a significant predictor of OS (P = 0.018) and EFS (P = 0.036). Relative measures of tumor size were not found to predict outcome. No relation was seen between tumor size and histologic response. CONCLUSIONS: Absolute tumor size at the time of diagnosis is significantly predictive of OS and EFS. If validated in a larger study, this indicator should be used in the design of risk-adapted treatment protocols for osteosarcoma.

Synergistic cytotoxicity in solid tumor cell lines between N-(4-hydroxyphenyl)retinamide and modulators of ceramide metabolism.

BACKGROUND: We previously reported that N-(4-hydroxyphenyl)retinamide (4-HPR, fenretinide) treatment caused large increases of ceramide levels in neuroblastoma cell lines and induced cell death by a combination of apoptosis and necrosis through p53 (also known as TP53)-independent and caspase-independent pathways. Our goal was to determine if several molecules that inhibit enzymes involved in ceramide metabolism-L-threo-dihydrosphingosine (safingol), d, l-threo-1-phenyl-2-hexadecanoylamino-3-morpholino-1-propanol (PPMP), and tamoxifen-enhanced 4-HPR-mediated cytotoxicity and/or affected ceramide levels. METHODS: Cellular lipids were quantified by radiolabeling and thin-layer chromatography. Cytotoxicity and cytotoxic synergy (expressed as combination index, where combination index <1 indicates synergy and >1 indicates antagonism) were measured in cultured cancer cell lines with the use of a fluorescence-based assay of cell viability employing digital imaging microscopy. Statistical tests were two-sided. RESULTS: 4-HPR increased ceramide levels by de novo synthesis. Safingol (1-4 microM) was incorporated into a stereochemical variant of ceramide and synergized with a 3:1 molar ratio of 4-HPR (3-12 microM), to produce a 100-fold to 10 000-fold (2 to 4 logs) increase in cytotoxicity relative to 4-HPR alone in neuroblastoma (combination index <0.1), lung (combination index <0.1-0.2), melanoma (combination index <0.1-0.2), prostate (combination index <0.1-1.0), colon (combination index 0.1-0.3), breast (combination index = 0.1-0.5), and pancreas (combination index = 0.2) cell lines, including p53 mutant and alkylator-resistant cell lines. The 4-HPR and safingol combination was cytotoxic in low-oxygen conditions and was minimally toxic to normal fibroblasts and bone marrow myeloid progenitor cells. Addition of agents that retard ceramide glucosylation and/or acylation, such as PPMP or tamoxifen, to 4-HPR or to the combination of 4-HPR and safingol further increased cytotoxicity to tumor cells. CONCLUSIONS: Combinations of 4-HPR and modulators of ceramide metabolism may form the basis for a novel chemotherapy that is functional under hypoxic conditions (e.g., such as those within tumors) and is p53 independent and caspase independent.

Effect of cyclosporine A on the corneal inflammatory response in herpes simplex virus keratitis.

The effects of cyclosporine A (CyA), a selective inhibitor of T-lymphocyte function, on the corneal inflammatory response in herpes simplex virus (HSV) stromal keratitis was followed during the course of experimental HSV keratitis in the rabbit. The corneal response, characterized by polymorphonuclear leukocytes (PMN) and mononuclear cells, is an immunologically specific event that is dependent on the presence of viral antigens and immune cells. CyA treatment during the course of HSV keratitis resulted in a more severe and persistent stromal disease and more anterior chamber involvement than that seen in the solvent control-treated HSV-infected animals. Clinical observations correlated well with histological studies which confirmed a greater incidence of mononuclear and PMN infiltrates throughout the anterior chamber and stroma in the CyA-treated animals. HSV antigens were present in the corneas from both infected groups as observed by immunofluorescence staining, but endothelial localization of HSV antigens was seen primarily in the CyA-treated animals, often accompanied by cells in the anterior chamber. No significant differences in IgG and IgM staining in the diseased corneas and anterior chamber were noted between the CyA-treated and solvent control groups which suggests that there was no local B-cell immunosuppression.

Effects of cyclosporine A on clinical and immunological parameters in herpes simplex keratitis.

The immunosuppressive effects of cyclosporine A (CyA) on the clinical and antiviral immune responses were examined in experimental herpes simplex virus (HSV) keratitis in the rabbit in order to clarify the role that immune lymphocytes play in herpetic stromal disease. Cyclosporine A was administered intramuscularly to rabbits daily starting from the time of corneal infection with HSV until day 14 postinfection. Control HSV-infected rabbits received daily injections of the solvent vehicle alone. HSV-infected rabbits receiving CyA treatment showed more severe and persistent stromal keratitis, and a greater incidence and duration of virus recovery from the cornea. Suppression of cellular immune responses to T cell mitogens, B cell mitogens (anti-rabbit immunoglobulins), and HSV antigens were observed in the CyA treatment group. These results show that in CyA-treated HSV-infected rabbits the antiviral immune responses are inhibited. Acute viral infections with cytopathic viruses such as HSV may therefore be more dramatic, suggesting that CyA may facilitate the potentiation of HSV infections ordinarily suppressed by immune cells.