BACKGROUND AND AIMS: There is scarce information about pediatric lymphoblastic lymphoma (LLy) in low and middle-income countries. We describe the clinical characteristics, treatment and outcome of a cohort of children and adolescents with LLy in Latin America (LA). METHODS: Retrospective study analyzing pediatric patients with LLy in 10 institutions of the St. Jude Global Alliance from nine LA countries between 2007 and 2017. RESULTS: One-hundred and twenty-six patients were included. Sixty (47.6%) had T-LLy, 49 (38.9%) B-LLy and in 17 (13.5%) the immunophenotype was unknown. Ninety-seven (77%) presented with stage III/IV disease, and 42 (33.3%) in critical conditions. In 30 cases (23.8%), the results of pathology diagnosis exceeded 15 days from biopsy, and 23 patients (18%) required a review at another institution. The EFS and OS at 5 years were 73% (SE 0.047) and 78% (SE 0.0435), respectively. Five-year abandonment-sensitive EFS and OS were 65% (SE 0.0477) and 70% (SE 0.0459), respectively. Events included relapse/progression (n=22), refractory disease (n =1) abandonment (n=11), induction death (n=4), death in complete remission (n=4), and second malignancies (n=1). CONCLUSIONS: A balanced proportion of LLy-T and B phenotypes was observed. Diagnosis was a challenge. Most of the patients presented with high-risk disease, and many in critical conditions. Toxic deaths and abandonment represented nearly half of the events. Improvements in diagnosis, supportive measures and follow up are imperative to improve the outcomes of pediatric LLy in Latin America.

Background/Objectives: High-risk Hodgkin lymphoma (HRHL) in children is a curable with combined modality therapy. The AHOPCA is a consortium of cancer centers from Central America. In 2004, AHOPCA implemented a guideline with a short course of chemotherapy (mStanfordV), strict diagnostics and radiation guidelines, aimed at reducing abandonment and improving outcomes. Methods: Newly diagnosed children less than 18 years of age with high-risk HL (Ann Arbor stages: IIB, IIIB, IV) from AHOPCA centers were staged with chest X-ray, and ultrasound or CT. Therapy was a modified StanfordV (mStanfordV) substituting cyclophosphamide for mechlorethamine and involved field radiation. Results: Of 219 patients with HRHL, 181 patients were eligible and evaluable;146 (81%) were boys, 22% being less than 6 years; 43 were stage IIB, 84 IIIB and 54 IV. Thirty-one (17%) abandoned therapy, 28 (15%) progressed, 30 (17%) relapsed and 8 (4%) died of toxicity. Radiation guidelines were not followed. Five-year abandonment-sensitive event-free survival and overall survival (AS-EFS, AS-OS±SE) for the cohort were 46±4% and 56±4%; 5-year AS-OS for stages IIB, IIIB and IV was 76±7%, 59±7%, and 35±7% (p=0.0006). Conclusion: Despite instituting a short treatment guideline, it did not improve the abandonment rate (17%) and did not achieve the reported outcomes of StanfordV. The cyclophosphamide dose used to replace merchlorethamine was inadequate. Despite strict guidelines, the radiation therapy application was inaccuarate. Weekly chemotherapy may have adversely affected abandonment of therapy by increasing the burden of travel-time. Based on these results, AHOPCA established a new abandonment strategy and a new guideline.

Cure rates for acute lymphoblastic leukemia (ALL), the most common childhood cancer have steadily improved over the past five decades. This is due to intensifying systemic therapy, recognizing and treating the central nervous system as a sanctuary site, and implementing modern risk stratification to deliver varying intensities of therapy based on age, presenting white blood count (WBC), sentinel somatic genetics, and therapy response. Recently, numerous Children’s Oncology Group trials have demonstrated the lack of benefit of intensifying traditional chemotherapy, providing evidence that new approaches are needed to cure the patients for whom cure has been elusive. Distinguishing those who require intensive or novel therapeutic approaches from others who will be cured with minimal therapy is key for future trials. Incorporating new genomic biomarkers and more sensitive measures of minimal/measurable residual disease (MRD) provide opportunities to achieve these goals.

Background: Patients with late, occurring ≥18 months post-diagnosis, isolated central nervous relapse (iCNS-R) of B-acute lymphoblastic leukemia (ALL) have excellent outcomes with chemotherapy plus cranial radiotherapy, with 5-yr overall survival (OS) approaching 80% in POG 9412. Subsequent relapse and radiation-related morbidity remain the causes of treatment failure and long-term sequelae. COG AALL02P2 aimed to maintain outcomes in patients with late iCNS-R using intensified chemotherapy and a decrease in cranial irradiation from 1800 to 1200 cGy. Procedures: COG AALL02P2 enrolled 118 eligible patients with B-ALL and early iCNS-R who received intensified systemic therapy, triple intrathecal chemotherapy and 1200 cGy cranial irradiation delivered at 12 months, with maintenance chemotherapy continuing until104 weeks post-diagnosis. Results: The 3-yr event-free and overall survival (EFS) and OS were 64.3±4.5% and 79.6±3.8%, with 46.1% (18/39) of relapses including the CNS. Of the 112 patients who completed therapy, 78 received protocol-specified radiation. Study enrollment was closed after interim monitoring analysis showed inferior EFS compared to POG 9412. Patients with initial NCI standard risk classification fared better than high risk patients. Conclusions: COG AALL02P2 showed inferior EFS but similar OS compared to POG 9412. Limitations included a small sample size, more intensive prior therapies, and a significant number of patients (34/118, 29%) who did not receive protocol-directed radiation due to early relapse prior to 1 year or did not otherwise follow the treatment plan. New approaches are needed to improve outcome for these patients and determine the optimal timing and dose of cranial radiation in the treatment of iCNS-R.