Bone Health in Osteosarcoma at Presentation and Its Impact on Cancer Treatment: A Case Series of 3 Pediatric Patients.

Osteosarcoma is the most common pediatric malignant bone tumor. Concomitant osteoporosis has typically been attributed to oncologic therapy. The present case series is aimed to describe 3 patients who presented with osteoporosis or osteopenia before, or early in, their oncology treatment. In our patients, bone health and its complications had significant impacts including pain, reduced mobility, prolonged admission, and delays in recovery. Our patients experienced improvement with resection of their primary tumor and with bisphosphonate infusion. Future studies are required to determine the prevalence osteoporosis at presentation of osteosarcoma and the role of bisphosphonates.

Clinically and biologically relevant subgroups of Wilms tumour defined by genomic and epigenomic analyses.

BACKGROUND: Although cure rates for Wilms tumours (WT) are high, many patients receive therapy with attendant long-term complications. Our goal was to stratify WT using genome-wide analyses to identify candidate molecular features for patients who would benefit from a reduction in therapy. METHODS: We generated DNA methylation and exome sequencing data on WT-kidney pairs (n = 57) and unpaired tumours (n = 27) collected either at our centre or by the Children's Oncology Group. Samples were divided into a discovery set (n = 32) and validation set (n = 52). RESULTS: Analysis of DNA methylation revealed two subgroups of WT with distinct features. Subgroup A has a similar DNA methylation profile to mature kidney, while Subgroup B has genome-wide dysregulation of DNA methylation. The rate of non-synonymous missense mutations and segmental chromosomal aberrations was higher in Subgroup B tumours, suggesting that this group has genome instability related to its epigenetic state. Subgroup A had a higher proportion of cases of bilateral disease. Tumours with high-risk histology or from patients who relapsed were only found in Subgroup B. CONCLUSION: We have identified subgroup-specific molecular events that could inform future work supporting more targeted therapeutic approaches and patient stratification. We propose a novel developmental tumour model based on these findings.

An eHealth decision-support tool to prioritize referral practices for genetic evaluation of patients with Wilms tumor.

Over 10% of children with Wilms tumor (WT) have an underlying cancer predisposition syndrome (CPS). Cognizant of increasing demand for genetic evaluation and limited resources across health care settings, there is an urgent need to rationalize genetic referrals for this population. The McGill Interactive Pediatric OncoGenetic Guidelines study, a Canadian multi-institutional initiative, aims to develop an eHealth tool to assist physicians in identifying children at elevated risk of having a CPS. As part of this project, a decisional algorithm specific to WT consisting of five tumor-specific criteria (age <2 years, bilaterality/multifocality, stromal-predominant histology, nephrogenic rests, and overgrowth features) and universal criteria including features of family history suspicious for CPS and congenital anomalies, was developed. Application of the algorithm generates a binary recommendation-for or against genetic referral for CPS evaluation. To evaluate the algorithm's sensitivity for CPS identification, we retrospectively applied the tool in consecutive pediatric patients (n = 180) with WT, diagnosed and/or treated at The Hospital for Sick Children (1997-2016). Odds ratios were calculated to evaluate the strengths of associations between each criterion and specific CPS subtypes. Application of the algorithm identified 100% of children with WT and a confirmed CPS (n = 27). Age <2 years, bilaterality/multifocality, and congenital anomalies were strongly associated with pathogenic variants in WT1. Presence of >1 overgrowth feature was strongly associated with Beckwith-Wiedemann syndrome. Stromal-predominant histology did not contribute to CPS identification. We recommend the incorporation of the WT algorithm in the routine assessment of children with WT to facilitate prioritization of genetic referrals in a sustainable manner.

Severity, change over time, and risk factors of anxiety in children with cancer depend on anxiety instrument used.

OBJECTIVE: The primary objective was to describe severity of anxiety among children and adolescents receiving chemotherapy for cancer or undergoing hematopoietic stem cell transplantation (HSCT). Secondary objectives were to describe how anxiety changes over time and determine factors associated with anxiety. METHODS: Participants were aged 8 to 18 and either receiving chemotherapy for cancer or undergoing HSCT for any indication. Respondents self-reported three anxiety measurement instruments at chemotherapy cycle or HSCT conditioning start and 3 weeks later. RESULTS: The proportion of participants with severe anxiety ranged from 10/77 (13.0%) to 22/77 (28.6%) depending on instrument used. Change over time also varied across instruments, with significant improvement observed with PedsQL (procedural) (P = 0.037) and PROMIS (P = 0.013). Factors associated with anxiety similarly varied by instrument. Older age was associated with more anxiety on the PedsQL (worry) (P = 0.036), and higher household income was associated with less anxiety on the MASC-10 (P = 0.028). CONCLUSIONS: While we found that a small proportion of patients met or exceeded thresholds for severe anxiety, we also noted that severity, change over time, and predictors of anxiety varied depending on instrument used. Future research should ensure that selected instruments measure the construct of interest and describe how anxiety is conceptualized in the study.

Outpatient High-dose Methotrexate for Osteosarcoma: It's Safe and Feasible, If You Want It.

BACKGROUND: High-dose methotrexate (HD MTX) is usually administered as an inpatient to those with osteosarcoma. We prospectively tested the safety and feasibility of administering HD MTX in the ambulatory setting. MATERIALS AND METHODS: In this single arm prospective observational study, eligible patients had previously completed 2 courses of HD MTX as an inpatient. On study, patients received MTX in hospital, discharged home and returned for daily assessment. Criteria to determine safety and feasibility included: (1) parent compliance with home instructions, (2) pump functioning/failure, and/or (3) admission for toxicity/noncompliance. Outpatient therapy was deemed feasible if <25% courses resulted in study event. Patient satisfaction was assessed. RESULTS: Six patients (median age, 13.5 y) with extremity osteosarcoma completed 35 courses of MTX. There were no study events-no hospitalizations or pump failures and all parents were compliant. The Data and Safety Committee concluded that with zero events in 35 courses, it was unlikely for outpatient MTX to be infeasible; study was thus terminated early. Participants reported value to stay out of hospital, permitted life to feel "more normal"; however, burden of daily commute to hospital was cited. CONCLUSIONS: The delivery of HD MTX is safe and feasible in patients with osteosarcoma.

DICER1 syndrome: Approach to testing and management at a large pediatric tertiary care center.

BACKGROUND: To expand the current knowledge of DICER1 syndrome and to propose criteria for genetic testing based on experience at a pediatric tertiary care center. PROCEDURE: This study involved a retrospective chart review of the 78 patients (47 probands and 31 family members) seen in the Cancer Genetics Program at The Hospital for Sick Children (SickKids) who were offered genetic testing for DICER1. RESULTS: Of 47 probands offered genetic testing for DICER1, 46 pursued testing: 11 (23.9%) carried a pathogenic variant and one proband (2.1%) carried a missense variant of uncertain significance with evidence for pathogenicity. Thirty-one family members of variant-positive probands were offered testing: eight of the 25 who agreed to testing carried their familial variant (32.0%). Overall, 20 patients were identified to have a variant in DICER1 (eight males, 12 females). Of these, 13 (65.0%) presented with clinical manifestations associated with the syndrome. The most common lesions were pleuropulmonary blastoma (PPB) (five of 20 patients, 25.0%) and pineoblastoma (three of 20 patients, 15.0%). The average age at which individuals were diagnosed with a primary neoplasm was 5.2 years (range 0.8-20 years, median 3.0). Surveillance at our institution, with a median follow-up time of 23 months, has identified PPB in two asymptomatic individuals. These lesions were identified at early stages, thus potentially reducing treatment-related morbidity and mortality. CONCLUSION: This study further delineates the DICER1 syndrome phenotype and demonstrates the feasibility of a DICER1 syndrome surveillance protocol for the early detection of tumors.

NUT midline carcinoma of the larynx: an international series and review of the literature.

AIMS: NUT midline carcinoma (NMC) is a rare undifferentiated and aggressive carcinoma that locates characteristically to the midline of the head and neck, and mediastinum. NMC is characterized by chromosomal rearrangements of the gene NUT, at 15q14. The BRD4 gene on 19q13 is the most common translocation partner forming a fusion oncogene, BRD4-NUT. By the end of 2014, the International NUT Midline Carcinoma Registry had 48 patients treated for NMC. Laryngeal NMC are exceedingly rare, and we report a case series of seven cases. METHODS AND RESULTS: We searched for cases in files of different hospitals as well as a thorough search of the English language literature. The diagnosis of NMC is made by demonstration of NUT rearrangement either by immunohistochemistry, fluorescence in-situ hybridization (FISH) or reverse transcription-polymerase chain reaction (RT-PCR). We found three previously published cases, and in this series add four cases of our own. CONCLUSIONS: NMC consists of monomorphic, often discohesive, cells with an epithelioid appearance and distinct nucleoli. The tumours typically show abrupt squamous differentiation. The mean age of the patients was 34 years, hence significantly lower than that for conventional laryngeal carcinoma. All tumours were located in the supraglottis and five patients died of the disease after 3, 7, 8, 9 and 11 months. Laryngeal NMC may be underdiagnosed, and an increased awareness among pathologists is warranted. NMC has characteristic morphological features, and positive immunostaining with the NUT antibody is diagnostic. Its aggressive behaviour demands a very intense treatment strategy and the need for its recognition is emphasized further by new promising treatment strategies.

Underlying undiagnosed inherited marrow failure syndromes among children with cancer.

To study the prevalence of pediatric cancer patients who have underlying inherited bone marrow failure syndrome (IBMFS), we retrospectively reviewed the medical records of newly diagnosed pediatric cancer patients at The Hospital for Sick Children from June 2009 to May 2010, focusing on clinical, laboratory, and treatment-related findings which may indicate underlying IBMFS. We found five (1.8%) patients out of 276 who had two or more findings suggestive of IBMFS. We conclude that a small fraction of patients with cancer have clinical features that indicate investigations to rule out underlying IBMFSs. A prospective study is needed to determine their prevalence.

Pediatric imaging in DICER1 syndrome.

BACKGROUND: DICER1 syndrome, arising from a mutation in the DICER1 gene mapped to chromosome 14q32, is associated with an increased risk of a range of benign and malignant neoplasms. OBJECTIVE: To determine the spectrum of abnormalities and imaging characteristics in patients with DICER1 syndrome at a tertiary pediatric hospital. MATERIALS AND METHODS: This retrospective analysis evaluated imaging in patients ≤18 years with DICER1 germline variants between January 2004 and July 2016. An imaging database search including keywords pleuropulmonary blastoma, cystic nephroma, pineoblastoma, embryonal rhabdomyosarcoma, ovarian sex cord-stromal tumor, ovarian Sertoli-Leydig cell tumor and DICER1 syndrome, was cross-referenced against the institutional Cancer Genetics Program database, excluding patients with negative/unknown DICER1 gene testing. RESULTS: Sixteen patients were included (12 females; mean age at presentation: 4.2 years, range: 14 days to 17 years), with surveillance imaging encompassing the following modalities: chest X-ray and CT; abdominal, pelvic and neck US; and brain and whole-body MRI. Malignant lesions (68.8% of patients) included pleuropulmonary blastoma (5), pineoblastoma (3), ovarian Sertoli-Leydig cell tumor (1), embryonal rhabdomyosarcoma (1) and renal sarcoma (1); benign lesions (37.5% of patients) included thyroid cysts (2), thyroid nodules (2), cystic nephroma (2), renal cysts (1) and pineal cyst (1). A common lesional appearance observed across modalities and organs was defined as the "cracked windshield" sign. CONCLUSION: The spectrum of DICER1-related tumors and the young age at presentation suggest early surveillance of at-risk patients is critical, while minimizing exposure to ionizing radiation.

Evolution of Renal Cysts to Anaplastic Sarcoma of Kidney in a Child With DICER1 Syndrome.

Anaplastic sarcoma of kidney (ASK) is a rare neoplasm recently associated with DICER1 mutations. We report a child with germline DICER1 mutation who developed ASK in preexisting septated renal cysts, which were likely cystic nephroma. From age 2.5 to 6 years, sonographic imaging illustrated changes in the size and number of renal cysts, followed at age 8.8 years by a mass, pathologically an ASK. Lung cysts resected in infancy were diagnosed retrospectively as pleuropulmonary blastoma. Both tumors had acquired somatic DICER1 mutations. Ultrasonographic evolution of renal cysts to ASK has not previously been documented. Children with both pulmonary and renal cysts are candidates for DICER1 mutation testing.

Accuracy of pre-contrast imaging in abdominal magnetic resonance imaging of pediatric oncology patients.

BACKGROUND: Safety concerns are increasingly raised regarding the use of gadolinium-based contrast media for MR imaging. OBJECTIVE: To determine the accuracy of pre-contrast abdominal MR imaging for lesion detection and characterization in pediatric oncology patients. MATERIALS AND METHODS: We included 120 children (37 boys and 83 girls; mean age 8.94 years) referred by oncology services. Twenty-five had MRI for the first time and 95 were follow-up scans. Two authors independently reviewed pre-contrast MR images to note the following information about the lesions: location, number, solid vs. cystic and likely nature. Pre- and post-contrast imaging reviewed together served as the reference standard. RESULTS: The overall sensitivity was 88% for the first reader and 90% for the second; specificity was 94% and 91%; positive predictive value was 96% and 94%; negative predictive value was 82% and 84%; accuracy of pre-contrast imaging for lesion detection as compared to the reference standard was 90% for both readers. The difference between mean number of lesions detected on pre-contrast imaging and reference standard was not significant for either reader (reader 1, P = 0.072; reader 2, P = 0.071). There was substantial agreement (kappa values of 0.76 and 0.72 for readers 1 and 2) between pre-contrast imaging and reference standard for determining solid vs. cystic lesion and likely nature of the lesion. The addition of post-contrast imaging increased confidence of both readers significantly (P < 0.0001), but the interobserver agreement for the change in confidence was poor (kappa 0.12). CONCLUSION: Pre-contrast abdominal MR imaging has high accuracy in lesion detection in pediatric oncology patients and shows substantial agreement with the reference standard for characterization of lesions. Gadolinium-based contrast media administration cannot be completely eliminated but can be avoided in many cases, with the decision made on a case-by-case basis, taking into consideration location and type of tumor.

Successful use of indwelling tunneled catheters for the management of effusions in children with advanced cancer.

BACKGROUND: Malignant pleural effusion (MPE) and ascites (MA) negatively impact quality of life of palliative patients. Treatment options are limited. This study's purpose is to examine the experience with indwelling tunneled catheters (ITCs) for management of MPE/MA in children with advanced cancer. METHODS: Children with MPE/MA who underwent ITC insertion (2007-2012) were retrospectively reviewed. Clinical, procedural, complication and outcome details were analyzed. RESULTS: PleurX® ITCs (n = 12) were inserted in eight patients (5-18 years) with sarcoma (11 MPE, 1 MA), achieving symptom relief and facilitating discharge home post ITC (median 2 days). Median survival following ITC was 51 days. There were two major complications: pain (n = 1), late site infection (n = 1), and five minor complications. Drainage ceased in four patients (pleurodesis/tumor progression). At time of death, six ITCs (five patients) were still in situ. CONCLUSIONS: ITC appears to be a safe, effective treatment for MPE/MA in advanced pediatric cancer, achieving symptomatic relief and discharge home.

Vertebral Body Reshaping after Fractures: An Important Index of Recovery in Glucocorticoid-Treated Children.

PURPOSE: In this 6-year study we identified factors associated with spontaneous vertebral body reshaping in glucocorticoid (GC)-treated children with leukemia, rheumatic disorders, and nephrotic syndrome. METHODS: Subjects were 79 children (mean age 7.4 years) who had vertebral fracture (VF) evaluation on lateral spine radiographs at least 1 year after VF detection. VF were graded using the modified Genant semiquantitative method and fracture burden for individuals was quantified using the spinal deformity index (SDI; sum of grades from T4 to L4). RESULTS: Sixty-five children (82.3%) underwent complete vertebral body reshaping (median time from VF detection to complete reshaping 1.3 years by Cox proportional hazard modeling). Of 237 VF, the majority (83.1%) ultimately reshaped, with 87.2% reshaping in the thoracic region vs 70.7% in the lumbar region (P = .004). Cox models showed that (1) every g/m2 increase in GC exposure in the first year after VF detection was associated with a 19% decline in the probability of reshaping; (2) each unit increase in the SDI at the time of VF detection was associated with a 19% decline in the probability of reshaping [hazard ratio (HR) = 0.81; 95% confidence interval (CI) = 0.71, 0.92; P = .001]; (3) each additional VF present at the time of VF detection reduced reshaping by 25% (HR = 0.75; 95% CI = 0.62, 0.90; P = .002); and (4) each higher grade of VF severity decreased reshaping by 65% (HR = 0.35; 95% CI = 0.21, 0.57; P < .001). CONCLUSION: After experiencing a VF, children with higher GC exposure, higher SDI, more severe fractures, or lumbar VF were at increased risk for persistent vertebral deformity.

Progressive transformation of germinal centers in children and adolescents: an intriguing cause of lymphadenopathy.

BACKGROUND: The clinical implications of a diagnosis of progressive transformation of germinal centers (PTGC) in children are not well known. METHODS: To better understand this entity, we conducted a retrospective review of all patients aged 0-18 years diagnosed with PTGC at our center between 1998 and 2010. RESULTS: Twenty-nine patients were identified. Median age at diagnosis was 11.5 years, and median duration of follow-up was 2.8 years. Thirteen patients (45%) had a single episode of PTGC with no other associated features. Five patients (17%) had recurrent PTGC. Four patients (14%) had PTGC associated with Hodgkin lymphoma (HL): one preceding, two concurrent, and one subsequently developed HL. The most commonly associated HL was nodular lymphocyte-predominant HL. Seven patients (24%) had PTGC associated with immune disorders, including lupus, Castleman disease, and probable autoimmune lymphoproliferative syndrome. Overall, 15 patients (52%) had more than one lymph node biopsy. The cumulative incidence of a second biopsy after a diagnosis of PTGC was 42.3% ± 12.2% at 4 years. PTGC was PET-avid in all four patients tested. CONCLUSIONS: PTGC is a nonspecific manifestation of a variety of associated conditions. There is a small risk of subsequent HL, and a larger risk of requiring multiple biopsies for recurrent PTGC. The presence of an immune disorder should be considered in patients who present with generalized lymphadenopathy, splenomegaly, immune cytopenias, and/or progression to HL. Routine surveillance imaging may not be required. Future research should determine the optimal surveillance strategy for patients with PTGC and the indications for repeat biopsies.

Reductions in Bone Mineral Density Are Apparent Early in Children With Prevalent Osteonecrosis Lesions Following Leukemia Therapy.

Osteonecrosis (ON) is a serious complication of childhood acute lymphoblastic leukemia. We determined the prevalence of osteonecrotic lesions in our patient population by a one-time multisite magnetic resonance imaging (MRI) more than 1 year following leukemia therapy. MRI findings were evaluated in relationship to clinical factors (including longitudinal changes in bone mineral density [BMD]). Eighty-six children enrolled in the Steroid Associated Osteoporosis in the Pediatric Population (STOPP) study were evaluated for ON at 3.1 ± 1.3 years following therapy. Thirty children had a total of 150 confirmed ON lesions (35%). Lumbar spine (LS) BMD Z-scores (mean ± SD) were low at diagnosis and similar between patients with and without ON (-1.09 ± 1.53 versus -1.27 ± 1.25, p = 0.549). LS BMD Z-scores declined from baseline to 12 months in children with ON (-0.31 ± 1.02) but not in those without (0.13 ± 0.82, p = 0.035); the hip BMD Z-scores from baseline to 24 months declined in both groups, but to a greater extent in those with ON (-1.77 ± 1.22) compared to those without (-1.03 ± 1.07, p = 0.045). At the time of the MRI, mean total hip and total body (TB) BMD Z-scores were lower in children with ON (hip -0.98 ± 0.95 versus -0.28 ± 1.06, p = 0.010; TB -1.36 ± 1.10 versus -0.48 ± 1.50, p = 0.018). Pain occurred in 11/30 (37%) with ON versus 20/56 (36%) without, p = 0.841. In multivariable models, older age at diagnosis (odds ratio [OR] 1.57; 95% confidence interval [CI], 1.15-2.13; p = 0.004), and hip BMD Z-score at MRI (OR 2.23; 95% CI, 1.02-4.87; p = 0.046) were independently associated with ON. Overall, one-third of children demonstrated ON after leukemia therapy. Those with ON had greater reductions in spine and hip BMD Z-scores in the first 1 and 2 years of therapy, respectively. Older age and lower hip BMD Z-scores at MRI were significantly associated with prevalent, off-therapy ON. These data assist in identifying children at risk of ON. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Nephron sparing surgery for unilateral Wilms tumor in children with predisposing syndromes: single center experience over 10 years.

PURPOSE: Unilateral Wilms tumors associated with predisposing syndromes are treated with preoperative chemotherapy followed by surgical resection. We describe our experience with nephron sparing surgery for Wilms tumor in this population at risk for metachronous lesions. MATERIALS AND METHODS: We conducted a retrospective review of all children with a predisposing syndrome who underwent nephrectomy for malignancy during a 10-year period (2000 to 2010). Data collected included age, mode of detection, tumor size, treatment, pathology results, followup time and recurrence episodes. RESULTS: From 2000 to 2010, 13 of 75 (19%) patients treated for Wilms tumor were diagnosed with predisposing syndrome(s). Eight patients with unilateral tumors were treated and had a mean age at diagnosis of 27 months (range 7 months to 9 years). Beckwith-Wiedemann syndrome, isolated hemihyperplasia, WAGR (Wilms tumor, Aniridia, Genitourinary abnormalities, mental Retardation) syndrome and isolated 11p13 deletion were the underlying diagnoses in 3, 2, 2 and 1 patient, respectively. All but 2 patients were diagnosed by screening ultrasound and 5 underwent preoperative chemotherapy. Median tumor size at surgery was 2.5 cm (range 1 to 13). Nephron sparing surgery was performed in 6 of 8 patients. Pathological study showed favorable histology Wilms tumor and nephrogenic rests in 6 and 2 patients, respectively. After a mean followup of 36 months (range 6 to 72) no recurrences were documented and all children had normal creatinine levels. CONCLUSIONS: Nephron sparing surgery appears safe for patients with unilateral Wilms tumor associated with predisposing syndrome(s), allowing for the preservation of renal function and good oncologic outcomes for the available followup time. If more studies confirm our observation, current recommendations for the surgical treatment of Wilms tumor may need to reemphasize the value of attempting nephron sparing surgery in this patient population.

Cranial nerve palsies in childhood parameningeal rhabdomyosarcoma.

BACKGROUND: Children with parameningeal rhabdomyosarcoma (PM RMS) and cranial nerve palsy (CNP) are at risk for permanent neurologic dysfunction. Clinicians often consider the use of emergent therapies such as expedited radiation and/or corticosteroids; however, there is a paucity of information describing the natural history of CNP in PM RMS. We sought to describe the clinical features of patients with PM RMS plus associated CNP and to evaluate the patient, disease, and treatment-related factors that impacted neurologic recovery. METHODS: We conducted a retrospective review of PM RMS cases treated at the Hospital for Sick Children between 1985 and 2010. RESULTS: Thirty-five children were treated for PM RMS, 19 (54%) of whom presented with CNP. Children with CNP were nine times more likely to have other high-risk features (cranial base bony erosion and/or intracranial extension) at the time of presentation than children without CNP (OR 9.6, 95% CI 1.69, 54.79, P = 0.013). In addition to commencing chemotherapy, 13 patients (68%) received expedited RT and corticosteroids, four (21%) corticosteroids alone, and two (11%) received only standard chemotherapy and RT. At last follow up of the 11 survivors, neurologic recovery was complete in five (45%), partial in five (45%), and absent in one (9%). CONCLUSIONS: In our cohort, recovery of PM RMS associated CNP was often incomplete despite multi-modal therapy. A larger cohort of patients is required to determine the utility of emergent initiation of radiation or corticosteroids. This study will facilitate the counseling of future families on the long-term neurologic recovery CNP in PM RMS.

Critical review of controversial issues in the management of advanced pediatric liver tumors.

Hepatocellular carcinoma (HCC) and hepatoblastoma (HB) are the most common primary tumors of liver in children. The management of patients with locally advanced, unresectable disease or those with extra-hepatic distant metastases provides substantial challenges to pediatric oncologists, hepatologists, and surgeons. Herein, we critically debate the two sides of three specific controversies: (1) the role of chemotherapy in the treatment of advanced pediatric HCC; (2) the indications for liver transplantation in children with HCC, specifically, the appropriateness of using adult Milan criteria; and (3) the role of liver trasplantation in children with unresectable HB that present with metastatic disease. Pediatr Blood Cancer 2011;56:1013-1018. © 2010 Wiley-Liss, Inc.

A Validated Risk Prediction Model for Bone Fragility in Children With Acute Lymphoblastic Leukemia.

Although bone fragility may already be present at diagnosis of pediatric acute lymphoblastic leukemia (ALL), routine performance of dual-energy X-ray absorptiometry (DXA) in every child is not universally feasible. The aim of this study was to develop and validate a risk prediction model for low lumbar spine bone mineral density (LS BMD Z-score ≤ -2.0) at diagnosis, as an important indicator for fracture risk and further treatment-related BMD aggravation. Children with ALL (4-18 years), treated according to the Dutch Childhood Oncology Group protocol (DCOG-ALL9; model development; n = 249) and children from the Canadian Steroid-Associated Osteoporosis in the Pediatric Population cohort (STOPP; validation; n = 99) were included in this study. Multivariable logistic regression analyses were used to develop the prediction model and to confirm the association of low LS BMD at diagnosis with symptomatic fractures during and shortly after cessation of ALL treatment. The area under the receiver operating characteristic curve (AUC) was used to assess model performance. The prediction model for low LS BMD at diagnosis using weight (ß = -0.70) and age (ß = -0.10) at diagnosis revealed an AUC of 0.71 (95% CI, 0.63-0.78) in DCOG-ALL9 and 0.74 (95% CI, 0.63-0.84) in STOPP, and resulted in correct identification of 71% of the patients with low LS BMD. We confirmed that low LS BMD at diagnosis is associated with LS BMD at treatment cessation (OR 5.9; 95% CI, 3.2-10.9) and with symptomatic fractures (OR 1.7; 95% CI, 1.3-2.4) that occurred between diagnosis and 12 months following treatment cessation. In meta-analysis, LS BMD at diagnosis (OR 1.6; 95% CI, 1.1-2.4) and the 6-month cumulative glucocorticoid dose (OR 1.9; 95% CI, 1.1-3.2) were associated with fractures that occurred in the first year of treatment. In summary, a prediction model for identifying pediatric ALL patients with low LS BMD at diagnosis, as an important indicator for bone fragility, was successfully developed and validated. This can facilitate identification of future bone fragility in individual pediatric ALL patients. © 2021 American Society for Bone and Mineral Research (ASBMR).

Performance of the McGill Interactive Pediatric OncoGenetic Guidelines for Identifying Cancer Predisposition Syndromes.

IMPORTANCE: Prompt recognition of a child with a cancer predisposition syndrome (CPS) has implications for cancer management, surveillance, genetic counseling, and cascade testing of relatives. Diagnosis of CPS requires practitioner expertise, access to genetic testing, and test result interpretation. This diagnostic process is not accessible in all institutions worldwide, leading to missed CPS diagnoses. Advances in electronic health technology can facilitate CPS risk assessment. OBJECTIVE: To evaluate the diagnostic accuracy of a CPS prediction tool (McGill Interactive Pediatric OncoGenetic Guidelines [MIPOGG]) in identifying children with cancer who have a low or high likelihood of having a CPS. DESIGN, SETTING, AND PARTICIPANTS: In this international, multicenter diagnostic accuracy study, 1071 pediatric (<19 years of age) oncology patients who had a confirmed CPS (12 oncology referral centers) or who underwent germline DNA sequencing through precision medicine programs (6 centers) from January 1, 2000, to July 31, 2020, were studied. EXPOSURES: Exposures were MIPOGG application in patients with cancer and a confirmed CPS (diagnosed through routine clinical care; n = 413) in phase 1 and MIPOGG application in patients with cancer who underwent germline DNA sequencing (n = 658) in phase 2. Study phases did not overlap. Data analysts were blinded to genetic test results. MAIN OUTCOMES AND MEASURES: The performance of MIPOGG in CPS recognition was compared with that of routine clinical care, including identifying a CPS earlier than practitioners. The tool's test characteristics were calculated using next-generation germline DNA sequencing as the comparator. RESULTS: In phase 1, a total of 413 patients with cancer (median age, 3.0 years; range, 0-18 years) and a confirmed CPS were identified. MIPOGG correctly recognized 410 of 412 patients (99.5%) as requiring referral for CPS evaluation at the time of primary cancer diagnosis. Nine patients diagnosed with a CPS by a practitioner after their second malignant tumor were detected by MIPOGG using information available at the time of the first cancer. In phase 2, of 658 children with cancer (median age, 6.6 years; range, 0-18.8 years) who underwent comprehensive germline DNA sequencing, 636 had sufficient information for MIPOGG application. When compared with germline DNA sequencing for CPS detection, the MIPOGG test characteristics for pediatric-onset CPSs were as follows: sensitivity, 90.7%; specificity, 60.5%; positive predictive value, 17.6%; and negative predictive value, 98.6%. Tumor DNA sequencing data confirmed the MIPOGG recommendation for CPS evaluation in 20 of 22 patients with established cancer-CPS associations. CONCLUSIONS AND RELEVANCE: In this diagnostic study, MIPOGG exhibited a favorable accuracy profile for CPS screening and reduced time to CPS recognition. These findings suggest that MIPOGG implementation could standardize and rationalize recommendations for CPS evaluation in children with cancer.