Cancer Prevalence in Children with Inborn Errors of Immunity: Report from a Single Institution.

BACKGROUND: Inborn Errors of Immunity (IEI) comprise several genetic anomalies that affect different components of the innate and adaptive responses, predisposing to infectious diseases, autoimmunity and malignancy. Different studies, mostly in adults, have reported a higher prevalence of cancer in IEI patients. However, in part due to the rarity of most of these IEI subtypes (classified in ten categories by the Primary Immunodeficiency Committee of the International Union of Immunological Societies), it is difficult to assess the risk in a large number of patients, especially during childhood. OBJECTIVE: To document the cancer prevalence in a pediatric cohort from a single referral institution, assessing their risk, together with the type of neoplasia within each IEI subgroup. METHOD: An extensive review of clinical records from 1989 to 2022 of IEI patients who at some point developed cancer before the age of sixteen. RESULTS: Of a total of 1642 patients with IEI diagnosis, 34 developed cancer before 16 years of age, showing a prevalence (2.1%) significantly higher than that of the general age matched population (0.22). Hematologic neoplasms (mostly lymphomas) were the most frequent malignancies. CONCLUSION: This study represents one of the few reports focused exclusively in pediatric IEI cases, describing not only the increased risk of developing malignancy compared with the age matched general population (a fact that must be taken into account by immunologists during follow-up) but also the association of the different neoplasms with particular IEI subtypes, thus disclosing the possible mechanisms involved.

Subsequent malignant neoplasms in the pediatric age in retinoblastoma survivors in Argentina.

BACKGROUND: Retinoblastoma survivors in low- and middle-income countries are exposed to high-intensity treatments that potentially place them at higher risk of early subsequent malignant neoplasms (SMNs). METHODS: We followed 714 (403 [56.4%] nonhereditary and 311 [43.5%] hereditary) retinoblastoma survivors diagnosed from August 1987 to December 2016, up to the age of 16 years. We quantified risk of SMNs with cumulative incidence (CI) and standardized incidence ratios (SIR) analysis. Multivariate regression Cox model was used to determine the association of treatments and risk of SMNs. RESULTS: Median follow-up was of 9 years (range: 0.18-16.9) and 24 survivors (3.36%) developed 25 SMNs (n = 22 hereditary, n = 2 nonhereditary). SMNs included sarcomas (osteosarcomas, Ewing sarcomas, rhabdomyosarcomas; n = 12), leukemias (n = 5), and central nervous system tumors (CNS; n = 3). All cases of acute myeloid leukemia (AML) and most of Ewing sarcomas occurred within 5 years of retinoblastoma diagnosis. The type of SMN was the main indicator of mortality (five of five patients with leukemias, six of 12 with sarcomas, and zero of three with CNS tumors died). Compared to the general population, radiation increased the risk of Ewing sarcoma in hereditary survivors by 700-fold (95% CI = 252-2422.6) and chemotherapy increased the risk of AML by 140-fold (95% CI = 45.3-436). The CI of SMNs for hereditary survivors was 13.7% (95% CI = 8.4-22.1) at 15 years. CONCLUSION: Retinoblastoma survivors from Argentina are at higher risk of developing SMNs early in life compared to the general Argentinean population, especially those treated with radiation plus chemotherapy. AML and Ewing sarcoma presented within 5 years of retinoblastoma diagnosis are associated with chemotherapy and radiation exposure.

Intracranial germ cells tumour: a single institution experience in Argentina.

BACKGROUND: Intracranial germ cell tumor (iGCT) represents a rare and heterogeneous group, with variable incidence and diverse treatment strategies. Although multiagent chemotherapy with reduced radiotherapy strategy has been applied by several cooperative groups in North America and Western Europe, there is a paucity of data to understand if this combined regimen is suitable in low-middle income countries (LMIC). METHODS: We evaluate the outcome in a cohort of iGCT treated by SIOP-CNS-GCT-96 strategy at hospital J.P Garrahan in Argentina over the last 20 years. Radiation field and dose included focal radiotherapy (FRT) before 2009 or focal radiotherapy plus whole ventricular radiotherapy (WVRT) after 2009 for localized germinoma and FRT or FRT plus WVRT or CSI for non germinomatous germ cell tumors (NGGCT) RESULTS: Sixty iGCT were identified; 39 germinoma and 21 NGGCT. Median follow-up was 6.57 years (range 0.13-20.5). 5-year PFS and OS were 83.5% (95% CI [165.53-223.2]) and 88.7% (95% CI [169.84-223.2]) for the germinoma group, while for the NGGCT group were 75% (95% CI [133.27-219.96]) and 64.2% (95% CI [107.38-201.81]) respectively. The localized germinoma group showed poor results between 2000 and 2009 with 5-year PFS and OS of 69 and 75% respectively, and an excellent outcome between 2010 and 2019 with a 5-years PFS and OS of 92.8 and 100%. A univariable analysis identified this difference in survival as related to the field of radiotherapy, specifically whole ventricular radiotherapy. FRT increased the risk of recurrence in localized germinoma, involving not only ventricular relapses; but spinal cord and disseminated disease as well. There were no relapses of localized NGGCT after FRT and FRT plus WVRT. CONCLUSION: Herein we demonstrate that intensive chemotherapy followed by FRT plus WVRT for germinoma is a feasible and effective strategy, warranting further study in the developing world.

No benefit of Interfant protocols compared to BFM-based protocols for infants with acute lymphoblastic leukemia. Results from an institution in Argentina.

BACKGROUND: Infant acute lymphoblastic leukemia (ALL) is an infrequent disease characterized by clinical and biological features related to poor prognosis. Adapted therapies were designed without a clear consensus regarding the best treatment options. We aimed to compare the outcome between infant ALL cases receiving Interfant versus BFM-based protocols. PROCEDURE: This is a retrospective observational study. From April 1990 to June 2018, infant ALL cases were enrolled in one of the five consecutive treatment protocols. Clinical, demographic, and biological features and outcome were evaluated. A comparative analysis was performed between Interfant protocols and BFM-based protocols. RESULTS: During the studied period, 1913 ALL patients were admitted and 116 (6%) were infants. Treatment administered was: ALL-BFM'90 (n = 16), 1-ALL96-BFM/HPG (n = 7), Interfant-99 (n = 39), Interfant-06 (n = 35), and ALLIC-BFM'2009 (n = 19). The 5-year event-free survival probability (EFSp) was 31.9(standard error [SE] 4.6)% for the entire population, with a significant difference among risk groups according to Interfant-06 criteria (P = .0029). KMT2A-rearrangement status was the strongest prognostic factor (P = .048), independently of the protocol strategy. The median time for relapse was 24.1 months for patients with minimal residual disease (MRD)-negative versus 11.5 months for those with MRD-positive (P = .0386). EFSp and cumulative relapse risk probability (CRRp) were similar. Interfant protocols showed comparable induction (8.1% vs 7.1%, P = .852) and complete remission mortality (21.6% vs 28.6%, P = .438), failing to reduce the relapse rate (48.5% vs 30.7%, P = .149). CONCLUSIONS: Interfant protocols and BFM-based protocols presented comparable results. The risk group stratification proposed by Interfant-06 was validated by our results, and MRD seems useful to identify patients with an increased risk of early relapse.

Ambulatory High-dose Methotrexate Administration in Pediatric Osteosarcoma Patients at a Single Institution in Argentina.

BACKGROUND: The purpose of this study was to evaluate the feasibility and safety of ambulatory high-dose methotrexate (HDMTX) administration with oral hydration, alkalinization, and leucovorin rescue. HDMTX (12 g/m) was given intravenously over 4 hours after urine alkalinization. Families and patients were instructed to continue ambulatory oral hydration and alkalinization to monitor urine pH and to adjust bicarbonate according to our institution's treatment algorithm. Clinical status and MTX levels were controlled every 24 hours, and oral leucovorin dose was adjusted accordingly. RESULTS: From April 2007 to December 2010, 150 of 447 courses of HDMTX (31.4%) were given on an outpatient basis, and 91.2% were successfully completed. The main causes of failure were poor oral tolerance (n=6) and fever (n=4). Most patients (81%) had MTX levels of <10 µmol/L 24 hours post-HDMTX; only in 1 course the levels were >50 µmol/L (50.96 µmol/L). Neutropenia grade III/IV was observed in 18.3% of the courses, grade III/IV leukopenia in 2.7%, and grade III/IV thrombocytopenia and anemia in 4.7%. Around 39% were associated with grade III/IV hepatic toxicity (asymptomatic hypertransaminasemia), grade III-IV gastrointestinal toxicity (vomiting and diarrhea) (5%), grade III-IV mucositis (4%), and none of the patients developed renal toxicity. CONCLUSIONS: Ambulatory HDMTX administration is feasible and safe in a population with poor resources in a developing country.

Outcome of Nephroblastoma Treatment According to the SIOP-2001 Strategy at a Single Institution in Argentina.

OBJECTIVE: Wilms tumor (WT) is a disease with a good prognosis. The aim of this study was to evaluate the outcome of patients with WT, treated according to the SIOP-2001 strategy. METHODS: A retrospective analysis of 141 consecutive patients with WT diagnosed at our institution between December 2001 and 2013 was performed. RESULTS: A total of 114 patients, median age 38.8 months (3 to 155 mo), were assessable for analysis. Fine-needle aspiration was initially performed in 88 patients (84.6%). Stage distribution was: I: 33%, II: 9.6%, III: 28%, IV: 14%, V: 14.9%. Six patients were stage III because of tumor spillage. The remaining patients received preoperative chemotherapy. Adjuvant chemotherapy was given without randomization, using vincristine-actinomycin for stage II and vincristine-doxorubicin-actinomycin plus radiotherapy for stage III. After a median follow-up of 52 months, 5-year overall survival and event-free survival were 91% and 85%, respectively. Overall survival according to stage was: I: 96%, II: 99%, III: 88%, IV: 78%, V: 90% (P=0.16). There was no significant difference in event-free survival (P=0.7). Seventy-eight (85.7%) were intermediate-risk and 11 (12%) were high-risk patients. Seventeen patients (14.9%) relapsed within 2 to 99 months (median 29.9 mo). Eight patients (7%) died of progressive disease. There were no treatment-related deaths. CONCLUSIONS: The SIOP-01 protocol proposes a treatment strategy that is feasible in our institution, achieving good results.

Children and Adolescent Hodgkin Lymphoma in Argentina: Long-term Results After Combined ABVD and Restricted Radiotherapy.

OBJECTIVE: Prospective analysis of clinical characteristics and long-term treatment results of a pediatric cohort with Hodgkin lymphoma (HL) treated in a single institution with ABVD and restricted radiotherapy (RT). PATIENTS AND METHODS: Between September 2000 and December 2015, 165 new consecutive assessable patients with HL were registered at our institution. Lymphocyte predominant nodular HL was excluded. Low risk (LR) patients were stage I and IIA (no bulky disease, <4 involved ganglionar areas and no lung hilar nodes), high risk (HR) was assigned to stage IV and any other stage with bulky mediastinum. The rest of the cohort was treated as intermediate risk (IR). Chemotherapy for LR and IR patients was 4 and 6 courses of ABVD regimen, respectively. These subsets received Low-dose involved field radiotherapy only in case of partial remission at the end of chemotherapy (21 Gy in initially involved areas, plus 14 Gy boost on residual disease). The HR group was treated with 6 courses of ABVD followed always with 21 Gy involved field radiotherapy if complete remission (CR) was achieved. A boost of 14 Gy was added to residual disease in case of partial remission. RESULTS: Median age was 10.6 years (range, 2.7 to 17 y). Males: 117 (71%); females: 48 (29%). Eighteen (11%) patients were stage I, 76 (46%) stage II, 35 (21%) stage III, and 35 (21%) stage IV. Forty-nine (30%) patients were assigned to LR, 49 (30%) to IR, and 67 (40%) to HR. Forty-three patients (26%) had "bulky" mediastinum involvement. One hundred thirty (79%) patients achieved CR after chemotherapy and 161 (98%) after RT. Four patients (all HR), did not respond to initial therapy and died of disease. One patient died in first CR due to adenovirus infection on previously therapy-related damaged lungs. Seventeen (10%) patients relapsed and 13 of them remained in second CR after further therapy. Seventy-six (46%) patients could be spared from RT and cured of disease (88% of LR patients and 67% of IR patients). With a median follow-up of 5 years, event free and overall survival were 0.84 (SE: 0.03) and 0.95 (SE: 0.02), respectively. Overall survival according to risk group was 1 for LR, 0.93 for IR, and 0.85 for HR. Acute toxicity and late effects due to therapy were not significant. CONCLUSIONS: The strategy of avoiding RT for LR and IR patients that responded completely to ABVD chemotherapy achieved very good results. For the HR group, the combination of 6 cycles of ABVD and Low-dose involved field radiotherapy was efficacious with similar good results. Nearly half of the patients could be cured without RT.

Second Neoplasms in Children Following a Treatment for Acute Leukemia and/or Lymphoma: 29 Years of Experience in a Single Institution in Argentina.

INTRODUCTION: Childhood acute leukemias (AL) and lymphomas achieve good survival rates. However, second neoplasms (SN) are a devastating event. METHODS: From August 1987 to December 2016, 34 of 3321 (1%) patients with diagnosis of AL or lymphoma developed SN. SN were AL (n=16), CNS tumors (n=5), endocrinal tumors (n=3), lymphomas (n=2), schwannoma (n=2) assorted sarcomas (n=4), retinal melanoma (n=1), and Vanek tumor (n=1). Median latency was 51 (range, 10 to 110) months for hematological malignancies and 119 (range, 25 to 236) months for solid tumors (P=0.001). RESULTS: A total of 33 patients with SN were treated taking into account cumulative doses of anthracyclines and radiotherapy. Twenty-three (67.6%) patients achieved complete remission (CR), 5 died early during therapy and 5 were refractory or partial responders. Six patients presented relapses of the SN and 1 died in CR. Seventeen patients remain alive in CR, with a median follow-up of 110 (range, 4 to 276) months. CONCLUSIONS: (1) The latency period was significantly longer for patients developing solid tumors than for those developing AL. (2) AL was the most frequent SN. (3) Our results strongly encourage giving standard therapy to SN, considering cumulative doses of previous treatment, since similar probabilities of surviving as "de novo" counterparts can be achieved.

Malignant extra-cranial germ cell tumors in children and adolescents. Results following the guidelines of SFOP/SFCE 95 Protocol.

Between September 1995 and December 2010, 99 new consecutive assessable patients with extra-cranial MGCT were treated according to SFOP/SFCE TGM95 Protocol. A "watch and wait" strategy for completely resected stage I-II was observed in cases with preoperative high tumor markers levels. Metastatic disease or alpha fetoprotein levels > 15 000 ng/ml cases were treated by VIP chemotherapy (etoposide, ifosfamide and CDDP) 4-6-courses. All other cases were treated by VBP (vinblastine, bleomycin, and CDDP) 3-5 courses. Median age for the whole group was 11.1 (r: 0-17) years. Males: 49, females: 50. Stage I: 19 patients, stage II: 16, stage III: 31 and stage IV: 3. Gonadal disease occurred in 77 cases. Of 21 completely resected stage I-II patients with MGCT who did not receive chemotherapy after surgery, 6 presented disease progression and were successfully treated by chemotherapy and remained disease-free. There were no significant differences in outcome according to age, gender, initial site, staging, and histological variant or high levels of alpha-fetoprotein. Initial non-responsiveness to VIP chemotherapy was the only significant unfavorable prognostic feature. With a median follow-up of 64 (r: 5-204) months, at 10 years EFS and OS estimates for the whole group were 0.82 (SE = 0.05) and 0.90 (SE = 0.03) respectively. Therapy results of MGCT treated with the SFOP/SFCE 95 strategy were excellent. Initial non-response to front line chemotherapy was the only significant adverse prognostic feature. The "watch and wait" strategy for completely resected disease with initial positive markers proved to be safe with optimal outcome.

Symptomatic bone langerhans cell histiocytosis treated at diagnosis or after reactivation with indomethacin alone.

This study evaluated the outcome of patients with symptomatic bone Langerhans cell histiocytosis (LCH) treated with indomethacin alone, either at diagnosis or after reactivation (after recurrence with previous therapies). We evaluated the nonrandomized use of oral indomethacin (2 mg/kg/d) in patients with symptomatic single-system bone LCH. From 1997 to 2012, 38 sequential patients were treated for a median of 4 months. Criteria of nonactive disease (NAD) after initial treatment (8 wk) were: no pain, no soft tissue involvement, no increase of size, or no new bone lesions. Twenty-two patients were treated at diagnosis: 18 showed NAD after initial treatment (2 patients who had bone reactivations were retreated with indomethacin and remain with NAD). Three patients improved and they are with NAD after treatment with indomethacin, steroids, or radiotherapy. One patient developed progressive bone disease and he is with NAD after treatment with steroids and chemotherapy. Sixteen patients were treated after reactivation, and all were with NAD after initial treatment: 5 reactivated and 4 remain with NAD after retreatment with indomethacin. Toxicity was not significant. We conclude that indomethacin is a well tolerated and active drug in patients with symptomatic bone disease. The results support the concept that chemotherapy may not be necessary for limited bone disease.

Lineage switch in childhood acute leukemia: an unusual event with poor outcome.

Although rarely, switches between lymphoid and myeloid lineages may occur during treatment of acute leukemias (AL). Correct diagnosis relies upon confirmation by immunophenotyping of the lineage conversion and certification that the same cytogenetic/molecular alterations remain despite the phenotypic changes. From a total of 1,482 AL pediatric patients, we report nine cases of lineage conversion (0.6%), seven from lymphoid (four Pro-B, two Pre-B, one Common) to myelo-monocytic, and two from myeloid (bilineal, with myeloid predominance) to Pro-B. Eight patients were infants. Switches were suggested by morphology and confirmed with a median of 15 days (range: 8 days-6 months) from initiation of therapy. Of note, in five cases switches occurred before day 15. Stability of the clonal abnormalities was assessed by cytogenetic, RT-PCR/Ig-TCR rearrangement studies in all patients. Abnormalities in 11q23/MLL gene were detected in seven cases. Treatment schedules were ALL (two pts), Interfant-99 (five pts) and AML (two pts) protocols. Despite changing chemotherapy according to the new lineage, all patients died. Our findings support the association of lineage switches with MLL gene alterations and the involvement of a common lymphoid B-myeloid precursor. New therapies should be designed to address these rare cases. Possible mechanisms implicated are discussed.

No advantage of a rotational continuation phase in acute lymphoblastic leukemia in childhood treated with a BFM back-bone therapy.

BACKGROUND: Our aim was to compare two different schedules of maintenance in pediatric acute lymphoblastic leukemia (ALL) treated with a BFM-based therapy, in a randomized study: an Arm with 6-MP + MTX (with or without vincristine and dexamethasone pulses) versus a more intensive continuation phase. PROCEDURE: From January 1996 to November 2002, 429 eligible children with ALL were enrolled in a protocol with BFM-based back-bone, followed by a randomized continuation phase in standard (SRG) and intermediate (IRG) risk groups. Patients were randomized between Arms A and B for SRG and B or C for IRG. Arms A and C consisted of 6-MP and MTX and in Arm C, six pulses of VCR and dexamethasone were added. Arm B combined four pairs of drugs rotated weekly. All risk-groups received maintenance until completing 2 years of therapy from diagnosis. RESULTS: With a median follow-up of 138 (range: 96-178) months, the overall pEFS (SE) was 72 (6)% for all patients and the different risk groups showed: SRG: 85 (3)%, IRG: 71 (1)%, and HRG: 42 (7)% (P-value ≤ 0.0001). The pDFS (SE) according to the assigned arm of maintenance was, for Arm A: 89 (3)% and for Arm B: 85 (4)% in SRG, and, for Arm B: 77 (4)% and for Arm C: 75 (4)% in IRG, at 10 years follow-up. There were no statistically significant differences in outcome between arms of maintenance for both risk groups. CONCLUSIONS: In protocols with initial BFM-based strategy, a more intensive continuation phase did not benefit any risk group of patients.

Clinical features and outcome of 2009 influenza A (H1N1) virus infections in children with malignant diseases: a case-control study.

BACKGROUND: The impact of the novel 2009 influenza A (H1N1) (2009 H1N1) virus in children with malignant diseases under therapy is not well known. OBJECTIVE: To analyze the clinical features and outcome in children with anticancer therapy infected with the 2009 H1N1 virus. PATIENTS AND METHODS: Descriptive, case-control study. Between May and July 2009, 24 cases of 2009 (H1N1) virus infections in children with malignant diseases were registered and 48 control cases of similar patients infected with common influenza A virus (IA) diagnosed between 2006 and 2008 were selected. RESULTS: Median age for cases was 72 months and for controls was 83 months (P ≥ 0.05). Children with IA showed neutropenia more frequently (52% vs. 17%), longer period of time with illness before diagnosis (3 d vs. 1.7 d), higher rate of earlier medical consultation (69% vs. 25%), and more antibiotic therapy courses (54% vs. 4%; P ≤ 0.05) than patients with 2009 H1N1 virus. Children infected with this virus presented hypoxemia more frequently (42% vs. 8%) and higher rates of intensive care unit hospitalizations (29% vs. 2%; P ≤ 0.05). Three children with 2009 H1N1 virus and 1 in the control group died. CONCLUSIONS: Children infected with 2009 H1N1 virus presented more morbidity and mortality than patients infected with seasonal IA virus.

Colorectal carcinoma in children and adolescents. / Carcinoma colorrectal en niños y adolescentes.

Although colorectal carcinoma (CRC) is the third most common type of cancer in adults, only 1-4 % of cases are reported in individuals younger than 25-30 years. Its presentation is usually confused with other diseases, leading to significant delays in diagnosis. Given its low incidence, few pediatricians will see a case throughout their practice. However, multiple hereditary syndromes during childhood predispose to CRC. The objective of this review is to provide an update on syndromes predisposing to CRC. Screening indications will be reviewed because an early diagnosis during localized stages is the main prognostic factor. In addition, patient and family genetic counseling tools will be enhanced. In turn, the clinical and histological manifestations and prognostic factors typical of CRC in the pediatric population will be discussed. Although treatment guidelines are extrapolated from the adult experience, therapy guidelines will be summarized here.

Si bien el carcinoma colorrectal (CCR) es la tercera enfermedad oncológica más frecuente en adultos, solo el 1-4 % ocurre en menores de 25-30 años. Su presentación suele confundirse con otras patologías, lo cual lleva a significativas demoras diagnósticas. Dada su baja incidencia, pocos pediatras se enfrentarán con algún caso a lo largo de su carrera. Sin embargo, existen en la niñez múltiples síndromes hereditarios que predisponen al CCR. El objetivo de esta revisión es brindar una actualización sobre los síndromes predisponentes al CCR. Se revisarán las indicaciones de tamizaje, dado que el diagnóstico precoz en estadios localizados es el principal factor pronóstico. Además, se fortalecerán las herramientas de consejería genética para el paciente y su familia. A su vez, se discutirán las manifestaciones clínicas e histológicas y los factores pronósticos propios del CCR en la población pediátrica. Si bien las guías de tratamiento se extrapolan de la experiencia en adultos, se resumirán los lineamientos terapéuticos.

Intensive Safety Monitoring of Rituximab (Biosimilar Novex® and the Innovator) in Pediatric Patients With Complex Diseases.

Although rituximab is widely used off-label for complex pediatric diseases, safety reports are limited. We aimed to report evidence of its use in clinical practice, to describe the incidence of adverse drug reactions (ADR) to rituximab biosimilar Novex® and innovator, and to identify risk factors for the development of ADR in a real-life follow-up cohort of pediatric patients with complex diseases. We conducted a prospective, longitudinal, observational, single-centre study in patients that received rituximab for any complex disease, and as part of an intensive pharmacovigilance program. Demographic, pharmacological, clinical, and drug-related data were collected for all patients. ADR-free survival, including infusion-related reactions (IRR) and delayed ADR (dADR), was estimated using Kaplan-Meier curves. Risk factors were evaluated by multivariable Cox regression models. In total, 77 patients (<19 y.o.) received 187 infusions of rituximab Novex® (n = 155) or innovator rituximab (n = 32) for neurologic (Neu), immune-hematologic-rheumatic (IHR), oncologic (O) diseases, and hematopoietic stem-cell transplantation (HSCT) or solid-organ transplantation (SOT). We recorded 29 IRR and 58 dADR that occurred in 27 (35.1%) and 29 (37.7%) patients, respectively. The respiratory tract was the most affected during IRR (29.6%) and hypogammaglobulinemia (37.9 %) was the most frequent dADR. First versus subsequent infusions (HR 5.4, CI95% 2.4-12.1, p<0.05), sex (boys vs. girls, HR 0.3, CI95% 0.1-0.8, and p<0.05), and diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 2.3, CI95% 1.02-5.4, and p < 0.05) were significantly associated with the development of IRR. For dADR, risk factors were diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 0.4, CI95% 0.2-0.9, and p < 0.05) and cumulative body surface area-normalized dosage (HR 1.0003, CI95% 1.0001-1.0006, and p < 0.05). The present is the largest real-world safety assessment of rituximab in Latin-American children with complex diseases supporting its use based on the overall acceptable safety. Identification of risk factors may contribute to optimization of off-label rituximab treatment in pediatrics.

Results of a prospective study for the treatment of unilateral retinoblastoma.

BACKGROUND: Few prospective studies about the management of unilateral retinoblastoma with pathology risk factors (PRFs) have been published. METHODS: Patients (n = 114) were divided into four groups: Group 1 (initial chemoreduction) (n = 17). Groups 2 and 3, included patients initially enucleated with no, or lower risk PRFs: (n = 65) and with higher risk PRFs (n = 30), respectively. The later included postlaminar optic nerve involvement (PLONI) (n = 23), tumor at resection margin of optic nerve (n = 5) or isolated scleral invasion (n = 2). Group 3 received adjuvant chemotherapy including a total eight cycles of carboplatin and etoposide, alternating with cyclophosphamide, idarubicin, and vincristine. Orbital radiotherapy (45 Gy) was given to patients with invasion to the resection margin. Group 4 included patients with metastatic disease (n = 2). They were given neoadjuvant therapy followed by surgery and high-dose chemotherapy and autologous stem cell rescue. RESULTS: Five-year event-free survival is 0.94 (1 for Group 1, 0.94 for Group 2, 0.96 for Group 3, and 0 for Group 4). Events included. Group 2: Systemic relapse (n = 2) and combined orbital and CNS relapse (n = 1). Relapsing patients had PLONI (n = 2) and isolated focal choroidal invasion (n = 1). Group 3: CNS relapse (n = 1) in a patient with tumor at the resection margin of optic nerve. Group 4: CNS relapse (n = 2). Only one relapsed patient survived. Eight of 17 eyes treated conservatively were preserved. CONCLUSIONS: The survival of patients with unilateral retinoblastoma was excellent and 60% were spared from adjuvant treatment. Our intensive regimen was likely to be effective for prevention of metastasis in patients with higher risk PRFs.

Desmoid-type fibromatosis in children. Clinical features, treatment response, and long-term follow-up

Desmoid-type fibromatosis (DF) is a tumor with high local recurrence rate. Sixteen patients (18 desmoid tumors) were retrospectively evaluated. Initial surgery was performed in 13/18 tumors, with complete resection in 6 (one with free margin and five with microscopic residual disease); 10/13 had local relapse. Eleven patients with 13 tumors underwent treatment with methotrexate-vinblastine. The response rate to chemotherapy was 54%, and up to 81% if stable disease cases were included. The best response was partial remission. Only 2 had grade 4 toxicity. Twelve of 15 patients had sequelae. In 8 cases sequelae were directly related to the surgical intervention and 3 of them were severe. The 5-year progression-free survival and overall survival were 30% and 93.3%, respectively. DF has a high local relapse rate, regardless of surgical margin involvement. Low dose chemotherapy achieved stable disease and even remission of the lesions with low toxicity. The high rate of sequelae is probably related to the initial surgery performed in the majority of patients and may be avoided by the use of neoadjuvant low dose chemotherapy.

La fibromatosis tipo desmoide (FD) es un tumor con alta tasa de recurrencia local. Dieciséis pacientes (18 tumores desmoides) fueron evaluados retrospectivamente. La cirugía inicial se realizó en 13/18 tumores, con resección completa en 6 (uno con margen libr e y cinco con margen microscópicamente comprometido); 10/13 tuvieron recaída local. Once pacientes con 13 tumores recibieron tratamiento con metotrexato/ vinblastina. La tasa de respuesta a la quimioterapia fue del 54% y de hasta el 81% si se incluyen los casos que lograron enfermedad estable. La mejor respuesta fue remisión parcial. Solo 2 tuvieron toxicidad grado 4. Doce de 15 pacientes tuvieron secuelas. En 8 casos, las secuelas estuvieron directamente relacionadas con la intervención quirúrgica y 3 de ellas fueron graves. La sobrevida libre de progresión a 5 años y la supervivencia global fueron del 30% y del 93.3%, respectivamente. La FD tiene una alta tasa de recaída local, independientemente del margen quirúrgico. Dosis bajas de quimioterapia lograron una enfermedad estable e incluso la remisión de las lesiones, con baja toxicidad. La alta tasa de secuelas probablemente esté relacionada con la cirugía inicial realizada en la mayoría de los pacientes y podría evitarse mediante el uso de quimioterapia neoadyuvante en dosis bajas, como sugieren las estrategias actuales de tratamiento.

Neuroblastoma in patients under 18 months. Single institution experience in Argentina.

The purpose of the study was to evaluate the outcome of patients under 18 months diagnosed with neuroblastoma. Between April 2006 and December 2013, 45 consecutive patients followed in Hospital de Pediatría Garrahan, were retrospectively reviewed. With a median age of 9.3 months (1-18 months) N-myc amplification was detected in 5 out of 38 patients, 1p deletion (del1p) in 4 patients, and 11q aberration in one patient. With a median follow-up of 53 (range: 6-109 months), at 24 months the event free survival (EFS) of all patients was 83% (SE 6%) and overall survival (OS) of 88% (SE 5%). Significant difference was found in OS and EFS between patients with stages L1, L2 and Ms vs. stage M (p = 0.01 and p = 0.01 respectively). EFS for each stage: L1 85% (SE 7%), L2 100%, MS 100%, vs. M 55% (SE 16%). OS: L1 90% (SE 6%), L2 100%, MS 100%, vs. M 66% (SE 15%). OS and EFS results are similar to those reported in international studies. However, better identification of biological prognostic factors will warr ant accurate staging and consequently an appropriate treatment.

El objetivo del trabajo fue evaluar las características y evolución de pacientes menores de 18 meses de edad, con diagnóstico de neuroblastoma. Se realizó un análisis descriptivo, retrospectivo entre abril/2006 y diciembre/2013, de 45 pacientes diagnosticados en forma consecutiva. La edad media fue 9.3 meses (1-18 meses). La amplificación del gen N-myc fue detectada en 5 pacientes, deleción del cromosoma 1p (del1p) en 4, y aberración de 11q en uno. Con una media de seguimiento de 53 meses (6-109 meses), la supervivencia libre de eventos (SLE) de todos los pacientes, a 24 meses fue 83% (ES 6%) y la supervivencia global (SG) de 88% (ES 5%). Se encontró diferencia significativa en la SG y SLE entre los pacientes con estadios L1, L2 y Ms, y aquellos con estadio M (p = 0.01). La SLE para cada estadio fue: L1 85% (ES 7%), L2 100%, MS 100%, M 55% (ES 16%). SG para cada estadio: L1 90% (ES 6%), L2 100%, MS 100%, y M 66% (ES 15%). Aunque los resultados de SG y SLE son similares a los publicados en estudios internacionales, una mejor identificación de los factores pronósticos biológicos permitirá una estadificación precisa y, en consecuencia, un tratamiento adecuado.

Laparoscopic total nephrectomy for Wilms tumor: Towards new standards of care.

INTRODUCTION: Laparoscopic total nephrectomy (LN) in malignant pediatric tumors remains controversial. For selected patients undergoing pre-operative chemotherapy in referral centers, LN has so far shown comparable results to the standard open technique. PURPOSE: To describe the inclusion criteria and preliminary results of laparoscopic nephrectomies (LN) for the treatment of unilateral Wilms tumors (WT). MATERIAL AND METHODS: Between November 2010 and January 2016, a retrospective study of patients with WT and undergoing pre-operative chemotherapy was performed. Inclusion criteria for candidates for LN were: unilateral tumors without venous invasion and central kidney localization. Tumor size and vascular thrombus were estimated with pre-operative computed tomography (CT) scan. Overall survival and recurrence rates were evaluated. RESULTS: Among 105 patients with WT, 14 underwent LN. Tumor bleeding or the lack of response to chemotherapy were not exclusion criteria. Median tumor volume for the patients undergoing LN was 71.5 cc (range 7-169). Patients with small tumors localized near the renal pole and candidates for nephron sparing surgery (NSS) were excluded. Estimated 5-year overall survival for all patients with WT during this period was 88.7% (88.1-103.1). Two patients underwent conversion. No recurrence or related death was found at a mean 32- month follow-up period. DISCUSSION: Reproducing the steps of the open nephrectomy when performing LN for malignant tumors allowed comparable oncologic results to the conventional procedure. However, upstaging of the tumor was not admissible and has become the main goal when approaching these patients laparoscopically. Preliminary results showed that the incidence of intraoperative rupture and incomplete node sampling were not an issue when comparing LN to open nephrectomy. On the other hand, LN for malignant tumors requires experience in advanced laparoscopy and oncologic surgery. Pre-operative chemotherapy changes the tumor's consistency and this is the key point as to why these patients are amenable to be approached laparoscopically. Lifting the tumor along with the fat to avoid capsule fraction, as well as changing the lens to the lateral port to achieve a correct view for lymph node sampling are some of the considerations when performing LN. CONCLUSIONS: Preliminary data suggest that LN for WT is feasible and has promising results in terms of event-free and overall survival. In patients undergoing pre-operative chemotherapy the correct selection for LN is crucial. Following the basic oncological precepts and in experienced centers, LN represents a plausible modality in the care of these patients.

Acute and sub-acute neurological toxicity in children treated for acute lymphoblastic leukemia.

Eighty percent of children with acute lymphoblastic leukemia (ALL) survive with current treatments. Neurotoxicity is an infrequent adverse event. We describe clinical presentations of neurological toxicity, phases of treatment when these adverse events were more frequent and patients ́ outcome. From January-1995 to December-2015, 1379 ALL cases were admitted. Neurotoxicity was diagnosed in 49 patients (3.6%) and classified according to neurological syndromes. Medical records, laboratory-tests and images were reviewed. The diagnosed syndromes were: a) Methotrexate-leukoencephalopathy (MLE) (35.4%); b) Cerebral-venous-sinus thrombosis following L-Asparaginase administration (26.5%); c) Vincristine-induced-vocal-cord paralysis (VVCP) (14.2%); d) Stroke-associated vasospasm (14%), after high-dose methotrexate e) Severe polyneuropathy (6.1%); f) Methotrexate myelopathy (2%); and g) Pseudotumor-cerebri (2%) associated with corticosteroid therapy. Neurotoxicity was diagnosed during induction in 55% of cases. We conclude that MLE was the most frequent syndrome. VVCP was observed in infants and Down patients. Seizure was the most common symptom and toxicity occurred mainly during induction phase.