Implementing a behavioral physical activity program in children and adolescent survivors of childhood cancer: a pilot randomized controlled trial

Purpose We aimed to document the acceptability (enrollment rate) and feasibility (phone call delivery rate) of implementing a behavioral PA intervention over 12 weeks, in addition to documenting its effects on patient-reported outcomes and physical functioning. This study also describes the costs of carrying out a behavioral PA intervention. A total of 40 participants were randomized in a 1:1 ratio. The tailored behavioral PA intervention was developed based on the most recent PA guidelines in pediatric oncology and on the COM-B framework to enact PA behavior changes. The prescription (frequency, intensity, time and type (FITT)) was adjusted each week during the weekly support calls. The control group did not receive the intervention. 26 males and 14 females (13.6 years old on average and 2.9 years post-cancer treatment on average) participated in our study. The acceptability rate was 90.9% and the feasibility rate was > 85%. We found that 85% improved PA frequency, 80% improved PA intensity, 100% improved PA time, and 50.0% achieved the recommended PA guidelines. No adverse events were reported over the duration of the intervention. Physical function improved with longer 6-minute walk distances in the intervention group (465.8 ± 74.5 m) than in the control group (398.7 ± 92.9 m) (p = 0.016). PROs scores for all participants were within the limits of the normal range. The estimated cost per participant of carrying out this intervention was USD $126.57. Our 12-week behavioral PA intervention, based on the COM-B framework, was found to be acceptable, feasible and safe in childhood cancer survivors. This study is an important step in the right direction to make exercise standard practice in pediatric oncology.

Accuracy of central neuro-imaging review of DIPG compared with histopathology in the International DIPG Registry

BACKGROUND

Diffuse intrinsic pontine glioma (DIPG) remains a clinico-radiologic diagnosis without routine tissue acquisition. Reliable imaging distinction between DIPG and other pontine tumors with potentially more favorable prognoses and treatment considerations is essential.

METHODS

Cases submitted to the International DIPG registry (IDIPGR) with histopathologic and/or radiologic data were analyzed. Central imaging review was performed on diagnostic brain MRIs (if available) by two neuro-radiologists. Imaging features suggestive of alternative diagnoses included nonpontine origin, <50% pontine involvement, focally exophytic morphology, sharply defined margins, and/or marked diffusion restriction throughout.

RESULTS

Among 286 patients with pathology from biopsy and/or autopsy, 23 (8%) had histologic diagnoses inconsistent with DIPG, most commonly nondiffuse low-grade gliomas and embryonal tumors. Among 569 patients with centrally-reviewed diagnostic MRIs, 40 (7%) were classified as non-DIPG, alternative diagnosis suspected. The combined analysis included 151 patients with both histopathology and centrally-reviewed MRI. Of 77 patients with imaging classified as characteristic of DIPG, 76 (99%) had histopathologic diagnoses consistent with DIPG (infiltrating grade II-IV gliomas). Of 57 patients classified as likely DIPG with some unusual imaging features, 55 (96%) had histopathologic diagnoses consistent with DIPG. Of 17 patients with imaging features suggestive of an alternative diagnosis, eight (47%) had histopathologic diagnoses inconsistent with DIPG (remaining patients were excluded due to nonpontine tumor origin). Association between central neuro-imaging review impression and histopathology was significant (p < 0.001), and central neuro-imaging impression was prognostic of overall survival.

CONCLUSIONS

The accuracy and important role of central neuro-imaging review in confirming the diagnosis of DIPG is demonstrated.

Volumetric endpoints in diffuse intrinsic pontine glioma: comparison to cross-sectional measures and outcome correlations in the International DIPG/DMG Registry

BACKGROUND

Cross-sectional tumor measures are traditional clinical trial endpoints; however volumetric measures may better assess tumor growth. We determined the correlation and compared the prognostic impact of cross-sectional and volumetric measures of progressive disease (PD) among patients with DIPG.

METHODS

Imaging and clinical data were abstracted from the International DIPG Registry. Tumor volume and cross-sectional product (CP) were measured with mint Lesion™ software using manual contouring. Correlation between CP and volume (segmented and mathematical [ellipsoid] model) thresholds of PD were assessed by linear regression. Landmark analyses determined differences in survival (via log-rank) between patients classified as PD versus non-PD by CP and volumetric measurements at 1, 3, 5, 7, and 9 months postradiotherapy (RT). Hazard ratios (HR) for survival after these time points were calculated by Cox regression.

RESULTS

A total of 312 MRIs (46 patients) were analyzed. Comparing change from the previous smallest measure, CP increase of 25% (PD) correlated with a segmented volume increase of 30% (R2 = 0.710), rather than 40% (spherical model extrapolation). CP-determined PD predicted survival at 1 month post-RT (HR = 2.77), but not other time points. Segmented volumetric-determined PD (40% threshold) predicted survival at all imaging timepoints (HRs = 2.57, 2.62, 3.35, 2.71, 16.29), and 30% volumetric PD threshold predicted survival at 1, 3, 5, and 9 month timepoints (HRs = 2.57, 2.62, 4.65, 5.54). Compared to ellipsoid volume, segmented volume demonstrated superior survival associations.

CONCLUSIONS

Segmented volumetric assessments of PD correlated better with survival than CP or ellipsoid volume at most time points. Semiautomated tumor volume likely represents a more accurate, prognostically-relevant measure of disease burden in DIPG.

DIPG-46. NON-DIPG PATIENTS ENROLLED IN THE INTERNATIONAL DIPG REGISTRY: HISTOPATHOLOGIC EVALUATION OF CENTRAL NEURO-IMAGING REVIEW

INTRODUCTION

The role of diagnostic biopsy in diffuse intrinsic pontine glioma (DIPG) remains in question. Distinguishing radiographically between DIPG and other pontine tumors with more favorable prognosis and different therapy is critically important.

METHODS

Cases submitted to the International DIPG registry with histopathologic data were analyzed. Central imaging review was performed by two neuro-radiologists; all cases with imaging features or histopathology suggestive of alternative diagnoses were re-reviewed. Imaging features suggestive of alternative diagnoses included non-pontine origin, <50% pontine involvement (without typical DIPG pattern on follow-up), focally exophytic morphology, sharply-defined margins, or marked diffusion restriction throughout.

RESULTS

Among 297 patients with pathology from biopsy and/or autopsy available, 27 (9%) had histologic diagnoses not consistent with DIPG, commonly embryonal tumors (n=9) and pilocytic astrocytomas (n=11). 163 patients had diagnostic MRI available for central neuroimaging review. Among 81 patients classified as characteristic of DIPG, 80 (99%) had histopathology consistent with DIPG (diffuse midline glioma, H3K27M-mutant, glioblastoma, anaplastic astrocytoma, diffuse astrocytoma). Among 63 patients classified as likely DIPG, but with unusual imaging features, 59 (94%) had histopathology consistent with DIPG. 19 patients had imaging features suggestive of another diagnosis, including 13 with non-pontine tumor origin; the remaining 6 all had histopathology not consistent with DIPG. Association between central imaging review and histopathology was significant (p<0.001).

CONCLUSIONS

The important role and accuracy of central neuroimaging review in diagnosing or excluding DIPG is demonstrated. In patients with pontine tumors for which DIPG is felt unlikely radiographically, biopsy may be considered to guide diagnosis and treatment.

Suprasellar central nervous system ganglioneuroblastoma: a case in a 9-year-old child and review of the literature

PURPOSE

Intracranial ganglioneuroblastomas are incredibly rare neuroectodermal tumors with only 8 described cases total, 5 of those having imaging findings METHODS: Here we present a 9-year-old female patient with 4 months progressive headaches, personality changes, and vomiting. We also present a review of the current literature of intracranial ganglioneuroblastomas.

RESULTS

Imaging demonstrated a partially calcified suprasellar mass measuring 4.6 × 6.3 × 5 cm composed of both solid and cystic components, diagnosed to be a ganglioneuroblastoma, with mass effect on the lateral and 3rd ventricles, with a midline shift of right to left of 6-7 mm. She was treated with subtotal surgical resection, an intensive chemotherapeutic regimen, and radiation and has no residual disease on imaging 1 year and 4 months status post-surgery.

CONCLUSION

To our knowledge, this is the first case of a ganglioneuroblastoma to mimic a craniopharyngioma based upon imaging findings and suprasellar location. As these cases are extremely rare, an optimal therapeutic regimen has not been defined. However, a combination of surgical resection, chemotherapy, and radiation therapy can be effective, as shown here with successful treatment and no evidence of residual disease.

Intracranial malignant peripheral nerve sheath tumor variant: an unusual neurovascular phenotype sarcoma case invading through the petrous bone

INTRODUCTION

Intracranial malignant peripheral nerve sheath tumor (MPNST) is exceedingly rare. Previously reported cases of intracranial MPNST have been associated with development within a prominent cranial nerve.

METHODS

This is the first report of an MPNST with both nerve sheath and vascular phenotype that follows the neurovascular bundle, without arising in a major cranial nerve or in the setting of neurofibromatosis type 1 (NF1).

RESULTS

The patient is a 14-year-old boy with a history of worsening headaches for the past several months, left-sided hearing loss, nausea, vomiting, and vertigo. MRI was performed that demonstrated a large extra-axial tumor compressing the left infratemporal posterior temporal region. The tumor was associated with significant destruction of the superior portion of the petrous bone and extension through the petrous into the upper posterior fossa, immediately below the tentorium. The patient underwent surgical debulking and adjuvant chemotherapy with doxorubicin and ifosfamide. Pathology demonstrated a variant malignant peripheral nerve sheath tumor with both nerve sheath and vascular phenotype by immunostains. The patient's symptoms improved following treatment.

CONCLUSION

We present the first reported case of an intracranial MPNST variant that developed along the neurovascular bundle as a sarcoma with both nerve sheath and vascular phenotype through the petrous bone and not associated with a major cranial nerve or with stigmata of neurofibromatosis type 1 (NF1). Although this is an extremely unusual presentation due to location and lack of prominent cranial nerves in that location, it is not unusual for benign nerve sheath tumors to follow the neurovascular bundle through foramen of cortical long bone or pelvis. This case suggests that physicians should incorporate intracranial MPNST variant into their differential diagnosis in the cranium, even when tumor is not located near a prominent cranial nerve. Surgical debulking and adjuvant chemotherapy with doxorubicin and ifosfamide has led to improvement in patient symptoms.

Outcomes of Measurable Residual Disease in Pediatric Acute Myeloid Leukemia before and after Hematopoietic Stem Cell Transplant: Validation of Difference from Normal Flow Cytometry with Chimerism Studies and Wilms Tumor 1 Gene Expression

We enrolled 150 patients in a prospective multicenter study of children with acute myeloid leukemia undergoing hematopoietic stem cell transplantation (HSCT) to compare the detection of measurable residual disease (MRD) by a "difference from normal" flow cytometry (ΔN) approach with assessment of Wilms tumor 1 (WT1) gene expression without access to the diagnostic specimen. Prospective analysis of the specimens using this approach showed that 23% of patients screened for HSCT had detectable residual disease by ΔN (.04% to 53%). Of those patients who proceeded to transplant as being in morphologic remission, 10 had detectable disease (.04% to 14%) by ΔN. The disease-free survival of this group was 10% (0 to 35%) compared with 55% (46% to 64%, P < .001) for those without disease. The ΔN assay was validated using the post-HSCT specimen by sorting abnormal or suspicious cells to confirm recipient or donor origin by chimerism studies. All 15 patients who had confirmation of tumor detection relapsed, whereas the 2 patients with suspicious phenotype cells lacking this confirmation did not. The phenotype of the relapse specimen was then used retrospectively to assess the pre-HSCT specimen, allowing identification of additional samples with low levels of MRD involvement that were previously undetected. Quantitative assessment of WT1 gene expression was not predictive of relapse or other outcomes in either pre- or post-transplant specimens. MRD detected by ΔN was highly specific, but did not identify most relapsing patients. The application of the assay was limited by poor quality among one-third of the specimens and lack of a diagnostic phenotype for comparison.

Radiation Necrosis Following Proton Beam Therapy in the Pediatric Population: a Case Series

Radiation necrosis after proton beam radiotherapy in the pediatric population is a finding that should be evaluated. We present two cases of radiation necrosis in pediatric patients who underwent proton beam radiation therapy following gross total resection of tumors. As seen in both our cases, patients often present with radiographic changes found on surveillance imaging. While the progression of disease should certainly be considered in any patient with radiographic changes, understanding the radiographic findings and the clinical course of radiation necrosis is paramount in order to prevent unnecessary surgical intervention.

Synchronous occurrence of metastatic Wilms tumor and ganglioneuroma

We describe a 4-year-old female patient with a persistent paraspinal mass following chemotherapy for Wilms tumor. A discordant response to chemotherapy prompted biopsy of the persistent mass, which revealed a ganglioneuroma. This report highlights the synchronous occurrence of different tumors in the same patient, and suggests that repeat biopsies should be considered when contiguous tumor masses do not respond as expected.