Outcome of pediatric chronic myeloid leukemia with management focusing on the monitoring of BCR-ABL fusion gene transcript levels.

Background and objective: Clinical, laboratory and outcome data were reviewed for pediatric patients who were diagnosed with chronic myeloid leukemia (CML) and managed at two tertiary care hospitals in Saudi Arabia, between January 2011 and December 2017 to assess the response to tyrosine kinase inhibitors (TKI) focusing on the monitoring of BCR-ABL fusion gene transcript levels and to look at the overall outcome. Methods: CML patients were identified based on the cytogenetic and molecular results. Results: Twelve pediatric patients diagnosed with CML at a median age of 8.4 year; treated with TKI as first-line therapy, 11 (91.7%) patients were started with imatinib (first-generation TKI), while one received dasatinib (second-generation TKI) due to his three-way Philadelphia chromosome sensitivity. Eight patients (72.7%) starting on imatinib were switched to dasatinib (six patients due to drug resistance, and two patients due to intolerance of Imatinib) and two patients (25%) of whom had already achieved major molecular response (MMR) on Imatinib. Response rate to imatinib in terms of achieving MMR as first-line therapy was achieved in five out of 11 patients (45.5%) and only three of them continued to maintain their MMR. Six out of eight patients who were switched to dasatinib achieved MMR. Two patients underwent hematopoietic stem cell transplant (SCT): one due to blast crisis and one due to the side effects of TKI. With a median follow-up time of 78 months (range, 40.5-108), all of our patients were alive at last update. Conclusion: We report an excellent outcome with an overall survival (OS) of 100% at 5-year and disease-free survival (DFS) of 91.7% (8.0%). All our patients achieved MMR and only one patient had loss of MMR on follow-up. Eight patients (66.7%) achieved complete molecular response (CMR).

Treatment-induced cerebral sinus venous thrombosis in childhood acute lymphoblastic malignancies: New risk factors to consider.

BACKGROUND: Cerebral sinus venous thrombosis (CSVT) is one of the many side effects encountered during acute lymphoblastic leukemia (ALL) therapy. Due to the rarity of cases, lack of data, and consensus management, no recommendations exist to target the population at risk. METHODS: This is a retrospective chart review of 229 consecutive patients diagnosed with ALL with an age range of 1-21 years, treated at the Children's Cancer Center of Lebanon between October 2007 and February 2018. RESULTS: The incidence of CSVT was 10.5%. Using univariate analysis, increased risk of CSVT was observed with male gender, age >10 years, T-cell immunophenotype, intermediate/high-risk disease, maximum triglyceride (TG) level of >615 mg/dl, presence of mediastinal mass, and larger body surface area (BSA). With multivariate analysis, the only statistically significant risk factors were maximum TG level, BSA, presence of mediastinal mass, and risk stratification (intermediate/high risk). CONCLUSION: Our study was able to unveil TG level of >615 mg/dl, mediastinal mass, and a larger BSA as novel risk factors that have not been previously discussed in the literature.

Isolated Central Nervous System Relapse Following Treatment Reduction in Low-risk Acute Lymphoblastic Leukemia at the Children's Cancer Center of Lebanon.

The aim of this trial was to decrease the incidence of life-threatening infections by decreasing the dose and the duration of dexamethasone treatment during maintenance therapy. This was a prospective, nonrandomized trial of low-risk acute lymphoblastic leukemia patients 1 to 18 years of age who were treated at the Children's Cancer Center of Lebanon (CCCL). Patients consecutively diagnosed between 2002 and 2013 were divided into groups 1 and 2 receiving total dexamethasone doses of 1144 and 618 mg/m, respectively. A total of 84 patients were assigned to group 1 and 33 patients to group 2. The 5-year cumulative incidence of isolated central nervous system relapse increased from (n=0% [95% confidence interval: 0%-4.4%]) in group 1 to 9.1% [95% confidence interval: 3%-23%]; P=0.021) in group 2. Decreasing cumulative dose of dexamethasone for low-risk childhood acute lymphoblastic leukemia patients aiming to avoid serious viral infections led to a significant increase in isolated central nervous system relapse.

Outcome of hematopoietic stem cell transplantation (HCT) from HLA-matched related donor for Fanconi anemia (FA) in adolescents and adults: a retrospective study by Eastern Mediterranean Blood and Marrow Transplantation Group (EMBMT).

Hematopoietic Stem Cell Transplantation (HSCT) is the only potentially curative treatment option for the hematologic complications that occur in patients with Fanconi anemia (FA). In this study, we present a retrospective multicenter analysis from the Eastern Mediterranean Blood and Marrow Transplantation Group (EMBMT) of matched related donor HSCT for FA in adolescents and adults transplanted between 1988 and 2015. Forty-five patients received HSCT with a median age at transplant of 18 years, the interquartile range (IQR) (15-23.5); 25 (55.6%) patients were females and 20 (44.4%) were males. Conditioning regimen was fludarabine-based in 29 (64.4%) patients, irradiation-based in five (11.1%) patients, and the remaining patients received other combinations. Indication for HSCT was bone marrow failure in 39 (86.7%) and myelodysplastic syndrome in six (13.3%) patients. Stem cell source was bone marrow in 22 (48.9%), peripheral blood in 20 (44.4%), umbilical cord blood in one (2.2%), and combination of bone marrow and cord blood in two (4.4%) patients. Twenty-seven (60%) patients engrafted and five (11.1%) had primary engraftment failure. The median time to neutrophil engraftment was 14 days (range 10-21 days); median time for platelet engraftment was 17 days (10-33 days). The probability of developing grade II-IV acute GVHD for all patients was 7.0% and chronic GVHD 36.6%. No new malignancies were reported. The OS probability was 53.6% (95% CI, 38.3-68.9%) with a median follow-up of 13 months (95% CI, 1-240). Our HLA-matched related HSCT results in AYA patients with FA compare favorably with other reported international registry data.

Clinical Prognostic Factors and Outcome in Pediatric Osteosarcoma: Effect of Delay in Local Control and Degree of Necrosis in a Multidisciplinary Setting in Lebanon.

PURPOSE: Outcomes in pediatric osteosarcoma have dramatically improved over the past few decades, with overall survival rates of 70% and 30% for patients with localized and metastatic disease, respectively. PATIENTS AND METHODS: We retrospectively reviewed clinical characteristics and outcomes of 38 patients treated between 2001 and 2012 at a single institution in Lebanon. All patients received a uniform three-drug chemotherapy regimen consisting of cisplatin, doxorubicin, and methotrexate. Ifosfamide and etoposide were added to the adjuvant treatment regimen in case of metastatic disease and/or poor degree of tumor necrosis (< 90%). RESULTS: After a median follow-up of 61 months (range, 8 to 142 months), patients with localized disease had 5-year overall and event-free survival rates of approximately 81% and 68%, respectively, whereas for metastatic disease, they were approximately 42%. The most common primary site was the long bones around the knee (n = 34; 89.5%). Six patients (15.8%) had metastatic disease to lungs, and three (7.9%) had synchronous multifocal bone disease with lung metastases. Adverse prognostic factors included nonlower extremity sites, metastasis, poor degree of necrosis, and delay of more than 4 weeks in local control. In bivariable analysis, only degree of necrosis was a prognostic predictor for survival and disease recurrence. CONCLUSION: Treatment of pediatric osteosarcoma in a multidisciplinary cancer center in Lebanon resulted in survival similar to that in developed countries. Delay in local control was associated with worse outcome. The only statistically significant inferior outcome predictor was poor degree of necrosis at the time of local control.

Genetic polymorphisms in candidate genes are not associated with increased vincristine-related peripheral neuropathy in Arab children treated for acute childhood leukemia: a single institution study.

OBJECTIVE: The aim of this study was to evaluate the potential association between candidate genetic polymorphisms and vincristine-related peripheral neuropathy in Arab children with acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: This is a retrospective evaluation of 133 Arab children treated for ALL at the Children's Cancer Center of Lebanon. Incidence and severity of, as well as the timing (in weeks) at which grade 2 or higher peripheral neuropathy occurred were recorded. Genotyping for ABCB1 (rs1045642), ABCB1 (rs1128503), ABCC2 (rs717620), CEP72 (rs924607), ETAA1 (rs17032980), and MTNR1B (rs12786200) was performed. RESULTS: A total of 26 (19.5%) individuals developed peripheral neuropathy, three of which occurred during the induction phase. No statistically significant associations were revealed for any of the polymorphisms with either incidence of vincristine-related toxicity, toxicity severity, or time to the first episode of grade 2 or higher vincristine-related peripheral neuropathy. CONCLUSION: This study presents the first pharmacogenetic analysis of vincristine-related peripheral neuropathy in children with ALL in an Arab country. We have shown that genetic polymorphisms in candidate genes are not associated with peripheral neuropathy secondary to chronic therapy with high-dose vincristine (2 mg/m) during the continuation phase. Concerning CEP72, our results are in line with the findings from the St Jude cohort of children treated for ALL with higher vincristine doses during chronic treatment. Larger high-throughput genetic analyses may be warranted to evaluate variants in other candidate genes such as CYP3A5 and reveal new nonpreviously reported alleles that may be peculiar to this region of the world.

Displaced children with cancer in Lebanon: A sustained response to an unprecedented crisis.

BACKGROUND: The unrest in Syria has resulted in an escalating refugee crisis. The postwar lack of health care infrastructure in Iraq has also resulted in Iraqis seeking health care in neighboring countries. Pediatric cancer is largely curable, although its treatment is expensive and complex. Strategies to implement pediatric cancer care with curative intent in these vulnerable populations are lacking. METHODS: To assess the feasibility of a collaborative approach for the provision of care to displaced children with cancer, this study reviewed the experience of the authors over the past 6 years in Lebanon, the country with the highest number of refugees per capita in the world. RESULTS: The American University of Beirut Medical Center and the Children's Cancer Center of Lebanon Foundation, in partnership with St. Jude Children's Research Hospital and the American Lebanese Syrian Associated Charities, established 3 successive funding programs to treat displaced children with cancer along with a continuous assessment of resource utilization. Between 2011 and 2017, 575 non-Lebanese children suspected to have cancer were evaluated. Of those, 311 received direct medical support, with 107 receiving full-treatment coverage and 204 receiving limited-workup/specialty services; the remaining 264 patients received medical consultations. CONCLUSIONS: In addition to providing lifesaving humanitarian support, the coordination of care delivery, including the establishment of guidelines for prioritization, can help direct future efforts. Many patients continue to be in dire need of support, and this should be addressed via collaboration among governmental, nongovernmental, and health care organizations. Cancer 2018;124:1464-72. © 2018 American Cancer Society.

Routine surveillance imaging after end of therapy for pediatric extracranial tumors: A retrospective analysis.

Frequent surveillance imaging is routine practice for pediatric patients after cancer therapy. This retrospective study evaluated the follow-up of 301 children with extracranial tumors diagnosed between 2002 and 2012, at a tertiary pediatric cancer center in Beirut, Lebanon. Recurrence occurred in 15% of patients, at a median of 12 months after end of primary therapy. Outcome was not different comparing patients with recurrence detected via imaging surveillance versus clinically. False positive findings in 55 patients led to further interventions. These results raise important questions regarding benefit of current surveillance practices as standard care, especially in countries with limited resources.

Pediatric cancer pathology review from a single institution: Neuropathology expert opinion is essential for accurate diagnosis of pediatric brain tumors.

BACKGROUND AND OBJECTIVES: Second pathology review has been reported to improve accuracy in oncologic diagnoses, including pediatric malignancies. We assessed the impact of second review on the diagnosis of pediatric malignancies at a tertiary care referral center in Beirut, Lebanon. METHODS: Pathology reports of patients treated at the Children's Cancer Institute in Lebanon were retrospectively reviewed for the period 2008-2016 and compared with same samples' diagnoses at St. Jude Children's Research Hospital. Diagnostic disagreements were divided into major, minor, and none based on their effect on diagnosis and/or patient management. RESULTS: Second review was requested for 171 cases, accounting for 19% of all cases during that period. Second opinion was mostly requested for brain tumors (62% of all brain tumor cases) and neuroblastoma for NMYC testing (65% of all neuroblastoma), while hematologic malignancies had the fewest referrals (3% of all hematologic cases). Major disagreements in second review occurred in 20 cases (12% of total), and minor disagreements in 21 cases (12% of total). The largest proportion of major disagreements (71%) occurred in pediatric brain tumors, and novel molecular tests contributed to the diagnosis in 55% of these cases. CONCLUSIONS: The availability of a specialized pediatric neuropathologist and a basic panel of relevant molecular testing are essential for appropriate diagnosis of pediatric brain tumors. Centers that do not have the available infrastructure in place can benefit greatly from second review referrals for this challenging subset of tumors.

Collaborative Pediatric Bone Tumor Program to Improve Access to Specialized Care: An Initiative by the Lebanese Children's Oncology Group.

BACKGROUND: Children with malignant bone tumors have average 5-year survival rates of 60% to 70% with current multimodality therapy. Local control modalities aimed at preserving function greatly influence the quality of life of long-term survivors. In developing countries, the limited availability of multidisciplinary care and limited expertise in specialized surgery and pediatric radiation therapy, as well as financial cost, all form barriers to achieving optimal outcomes in this population. METHODS: We describe the establishment of a collaborative pediatric bone tumor program among a group of pediatric oncologists in Lebanon and Syria. This program provides access to specialized local control at a tertiary children's cancer center to pediatric patients with newly diagnosed bone tumors at participating sites. Central review of pathology, staging, and treatment planning is performed in a multidisciplinary tumor board setting. Patients receive chemotherapy at their respective centers on a unified treatment plan. Surgery and/or radiation therapy are performed centrally by specialized staff at the children's cancer center. Cost barriers were resolved through a program development initiative led by St Jude Children's Research Hospital. Once program feasibility was achieved, the Children's Cancer Center of Lebanon Foundation, via fundraising efforts, provided continuation of program-directed funding. RESULTS: Findings over a 3-year period showed the feasibility of this project, with timely local control and protocol adherence at eight collaborating centers. We report success in providing standard-of-care multidisciplinary therapy to this patient population with complex needs and financially challenging surgical procedures. CONCLUSION: This initiative can serve as a model, noting that facilitating access to specialized multidisciplinary care, resolution of financial barriers, and close administrative coordination all greatly contributed to the success of the program.

Cerebral sinus venous thrombosis during childhood acute lymphoblastic leukemia therapy: Risk factors and management.

BACKGROUND: Cerebral sinus venous thrombosis (CSVT) is a rare but serious complication of childhood acute lymphoblastic leukemia (ALL) therapy. No available consensus exists regarding its risk factors and appropriate management due to the rarity of cases. PROCEDURES: Out of 209 ALL patients aged 1-21 years treated at the Children's Cancer Center of Lebanon between May 2002 and May 2015, 13 developed CSVT during therapy. Patient characteristics, clinical management, and outcomes were studied. RESULTS: The incidence of CSVT was 6.2% (95% confidence interval [CI]: 3.4-10.4). Using univariate analysis, increased risk of CSVT was observed with age >10 years (odds ratio [OR]: 3.56, 95% CI: 1.13-11.2), T-cell immunophenotype (OR: 4.14, 95% CI: 1.16-14.7), and intermediate/high risk disease (OR: 3.4, 95% CI: 1.03-11.7). The only statistically significant risk factor by multivariate analysis was the treatment as per the intermediate-/high-risk protocol (HR: 15.6, 95% CI: 1.43-171.3). Most cases (77%) occurred in the postinduction phases of treatment while receiving a combination of asparaginase and dexamethasone rather than prednisone. Treatment with low molecular weight heparin (LMWH) for a minimum of 3 months and until significant radiological improvement is observed resulted in 100% survival rate. All but one patient had complete neurological recovery. CONCLUSIONS: CSVT is an important complication of childhood ALL therapy. Postinduction combined asparaginase and dexamethasone intensive treatment for intermediate-/high-risk patients was the most important risk factor. Treatment with LMWH for a minimum of 3 months, and until asparginase therapy is over, with major radiological improvement seems to be effective and feasible.

NUDT15 and TPMT genetic polymorphisms are related to 6-mercaptopurine intolerance in children treated for acute lymphoblastic leukemia at the Children's Cancer Center of Lebanon.

BACKGROUND: Interindividual variability in thiopurine-related toxicity could not be completely explained by thiopurine S-methyltransferase (TPMT) polymorphisms, as a number of patients who are homozygous wild type or normal for TPMT still develop toxicity that necessitates 6-mercaptopurine (MP) dose reduction or protocol interruption. Recently, few studies reported on an inherited nucleoside diphosphate-linked moiety X motif 15 (NUDT15) c.415C>T low-function variant that is associated with decreased thiopurine metabolism and leukopenia in childhood acute lymphoblastic leukemia (ALL) and other diseases. PROCEDURES: The aim of this study is to measure the frequency of TPMT and NUDT15 polymorphisms and assess whether they are predictors of MP intolerance in children treated for ALL. One hundred thirty-seven patients with ALL of whom 121 were Lebanese were evaluated. MP dose intensity was calculated as the ratio of the tolerated MP dose to planned dose during continuation phase to maintain an absolute neutrophil count (ANC) dose above 300 per µl. RESULTS: One patient was NUDT15 heterozygous TC and tolerated only 33.33% of the planned MP dose, which was statistically significantly different from the median-tolerated MP dose intensity of the rest of the cohort (76.00%). Three patients had the TPMT*3A haplotype and tolerated 40.00-66.66% of the planned MP dose, which was also statistically significantly different from the rest of the cohort. CONCLUSIONS: This is the first report on the association of TPMT and NUDT15 polymorphisms with MP dose intolerance in Arab patients with ALL. Genotyping for additional polymorphisms may be warranted for potential gene/allele-dose effect.

Chimerism Analysis of Cell-Free DNA in Patients Treated with Hematopoietic Stem Cell Transplantation May Predict Early Relapse in Patients with Hematologic Malignancies.

Background. We studied DNA chimerism in cell-free DNA (cfDNA) in patients treated with HSCT. Methods. Chimerism analysis was performed on CD3+ cells, polymorphonuclear (PMN) cells, and cfDNA using 16 small tandem repeat loci. The resulting labeled PCR-products were size-fractionated and quantified. Results. Analyzing samples from 191 patients treated with HSCT for nonneoplastic hematologic disorders demonstrated that the cfDNA chimerism is comparable to that seen in PMN cells. Analyzing leukemia patients (N = 126) showed that, of 84 patients with 100% donor DNA in PMN, 16 (19%) had evidence of clinical relapse and >10% recipient DNA in the plasma. Additional 16 patients of the 84 (19%) showed >10% recipient DNA in plasma, but without evidence of relapse. Eight patients had mixed chimerism in granulocytes, lymphocytes, and plasma, but three of these patients had >10% recipient DNA in plasma compared to PMN cells and these three patients had clinical evidence of relapse. The remaining 34 patients showed 100% donor DNA in both PMN and lymphocytes, but cfDNA showed various levels of chimerism. Of these patients 14 (41%) showed laboratory or clinical evidence of relapse and all had >10% recipient DNA in cfDNA. Conclusion. Monitoring patients after HSCT using cfDNA might be more reliable than cellular DNA in predicting early relapse.

Wilms tumor: Successes and challenges in management outside of cooperative clinical trials.

OBJECTIVE/BACKGROUND: Management of Wilms tumor (WT) in children depends on a multidisciplinary approach to treatment, and outcomes have significantly improved as reported by cooperative group clinical trials. Here, we review the clinical outcomes of patients with WT and identify challenges and barriers encountered in multidisciplinary management outside of cooperative clinical trials. METHODS: We retrospectively reviewed the clinical records of 35 children with WT treated between April 2002 and June 2013 at the Children's Cancer Institute in Lebanon. RESULTS: Upfront resection was performed in 23 cases. Biopsies were performed for Stage V tumors (n=4), those with unresectable tumors or inferior vena caval thrombus (n=5), and patients who had partial surgery performed elsewhere prior to presentation (n=2). One patient died due to toxicity prior to surgery. The tumor was Stage I in eight patients, Stage II in five patients, Stages III and IV in nine patients each, and bilateral (Stage V) in four patients. Adherence to The National Wilms Tumor Study-5 recommendations was adequate. At the time of analysis, 30 patients were free of disease and four patients had relapse-all having metastatic disease initially. CONCLUSION: The National Wilms Tumor Study-5 therapy resulted in favorable outcomes in children with nonmetastatic Wilms tumor in the setting of a multidisciplinary approach to therapy and resolution of financial barriers to medical care. Upstaging due to prior intervention and lung radiation therapy to all those with computed tomography-detected lung nodules may both have resulted in overtreatment of a subset of patients. Finally, the relatively high incidence of bilateral tumors suggests the need for further genetic and molecular studies in this patient population.

Outcome of pediatric patients with lymphoma following stem cell transplant: a single institution report.

Hematopoietic stem cell transplant (HSCT) is recommended for pediatric patients with relapsed/refractory lymphoma even though the evidence for this is limited. We retrospectively reviewed records of 57 patients (29 Hodgkin lymphoma [HL], 28 non-Hodgkin lymphoma [NHL]) who underwent HSCT between 1995 and 2012. All demonstrated chemoresponsiveness prior to HSCT and 44 patients had a complete response. All underwent myeloablative conditioning, 38 chemotherapy-based and 19 total body irradiation-based. Forty-one patients received autologous and 16 allogeneic HSCT. Twelve (21%) died within 100 days post-HSCT, and 25 patients relapsed at a median of 1.6 months post-HSCT. Three patients developed second malignant neoplasms. Five-year overall survival (OS) was 50.5% and event-free survival (EFS) was 43.4%. Outcomes for HL were significantly better than those for NHL (OS 61.9% vs. 38.7% [p = 0.005] and EFS 60.4% vs. 26% [p = 0.008]). In summary, approximately half of all pediatric patients with lymphoma who failed first-line therapy and demonstrated chemosensitivity to second-line therapy can be salvaged with HSCT.

Factors affecting the outcome of related allogeneic hematopoietic cell transplantation in patients with Fanconi Anemia.

Hematopoietic cell transplantation (HCT) can cure bone marrow failure in patients with Fanconi Anemia (FA), and it is generally accepted that these patients should receive low-intensity conditioning because of the underlying DNA repair defect in their cells. Outcomes for recipients of matched related HCT have generally been favorable, but only a few studies have scrutinized the factors that may affect the eventual outcome of these patients. This retrospective analysis of 94 pediatric patients with FA who underwent related HCT at King Faisal Specialist Hospital & Research Center was carried out to attempt to identify factors that may affect outcome. Results showed overall survival (OS) probabilities of 92.5%, 89%, and 86% at 1, 5, and 10 years, respectively. In univariate analysis, use of higher dose cyclophosphamide (CY) (60 mg/kg) conditioning was associated with a better 10-year OS than lower dose CY (20 mg/kg) conditioning (91% versus 82%, respectively; P = .035), and use of radiation-containing regimens was associated with a significantly lower 10-year OS than nonradiation regimens (76% versus 91%, respectively; P = .005). Of the 4 regimens used in this study, the fludarabine-based regimen was associated with the highest survival (95.2%; P = .034). The use of the higher dose CY (60 mg/kg) was associated with a significantly increased incidence of hemorrhagic cystitis (HC) (20% versus 5.6% respectively; P = .049). Three patients (3%) developed squamous cell carcinoma (2 oropharyngeal and 1 genitourinary), at 9.4, 5.4, and 13.3 years after HCT; 2 of them had radiation-containing conditioning. In conclusion, our data suggest that although using a higher dose CY (60 mg/kg) conditioning regimen may be associated with better survival, it is also associated with a significantly increased risk of HC. The addition of fludarabine to the low-dose CY (20 mg/kg) is associated with the best survival. On the other hand, radiation-containing regimens are associated with significantly lower survival.