Analysis of KRAS and NRAS Gene Mutations in Arab Asian Children With Acute Leukemia: High Frequency of RAS Mutations in Acute Lymphoblastic Leukemia.

BACKGROUND: KRAS and NRAS gene mutations are frequently observed in childhood leukemia. The objective of this study was to determine the frequency of RAS mutations and the association between RAS mutations and other genetic aberrations in Arab Asian children with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML). METHODS: Diagnostic samples of 485 patients (<18 years) with acute leukemia from Iraq and Jordan were obtained, using Flinders Technology Associates filter papers. Polymerase chain reaction and direct sequencing were performed in Japan. RESULTS: RAS mutations were detected in 86/318 (27%) of ALL cases and 35/167 (21%) of AML cases. The frequency of NRAS mutation was similar to that of KRAS mutation in ALL. Two RAS mutations were detected in nine patients. Among 264 Iraqi patients with ALL, RAS mutation was significantly associated with lower initial white blood cell count. Of 57 patients with chimeric transcripts, only two patients with either TEL-AML1 or E2A-PBX1 had KRAS mutation. The frequency of NRAS mutation was four times higher than that of KRAS mutation in AML. FAB-M4 and M5 subsets were associated with RAS mutation. Among 134 Iraqi patients with AML, 18 patients had RAS mutations and other genetic aberrations. In particular, 9 of 25 (36%) with MLL-rearrangement had RAS mutations. CONCLUSION: The prevalence of oncogenic RAS mutations was higher among Arab Asian children than in other countries. RAS mutations in AML were found to coexist with other genetic aberrations, particularly MLL rearrangement.

Analysis of class I and II aberrations in Iraqi childhood acute myeloid leukemia using filter paper cards.

The lack of molecular diagnosis in the field of cancer in Iraq has motivated us to perform a genetic analysis of pediatric acute myelogenous leukemia (AML), including class I and II aberrations. Peripheral blood or bone marrow cells were collected from 134 AML children aged ≤15 years. Flinders Technology Associates (FTA) filter paper cards were used to transfer dried blood samples from five Iraqi hospitals to Japan. DNA sequencing was performed to identify class I mutations. Nested RT-PCR was used to detect class II aberrations, except that MLL rearrangement was detected according to long distance inverse-PCR. NPM1 and FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutations were analyzed by GeneScan using DNA template. Among 134 Iraqi pediatric AML samples, the most prevalent FAB subtype was M2 (33.6 %) followed by M3 (17.9 %). Class I mutations: 20 (14.9 %), 8 (6.0 %), and 8 (6.0 %) patients had FLT3-ITD, FLT3-TKD, and KIT mutations, respectively. Class II mutations: 24 (17.9 %), 19 (14.2 %), and 9 (6.7 %) children had PML-RARA, RUNX1-RUNX1T1, and CBFB-MYH11 transcripts, respectively. MLL rearrangements were detected in 25 (18.7 %) patients. NPM1 mutation was detected in seven (5.2 %) cases. Collectively, approximately 30 % of AML children were proved to carry favorable prognostic genetic abnormalities, whereas approximately 10 % had high FLT3-ITD allelic burden and needed a special treatment plan including allogeneic hematopoietic stem cell transplantation. Acute promyelocytic leukemia (APL) was frequent among Iraqi pediatric AML. It is likely that molecular diagnosis using FTA cards in underdeveloped countries could guide doctors towards an appropriate treatment strategy.

Frequent coexistence of RAS mutations in RUNX1-mutated acute myeloid leukemia in Arab Asian children.

BACKGROUND: RUNX1 mutation plays an important role in adult leukemic transformation. However, its contribution to the development of childhood leukemia remains unclear. In the present study, we analyzed point mutations of RUNX1 gene in children and adolescents with acute myeloid leukemia (AML) from Iraq and Jordan. PROCEDURE: Bone marrow and/or peripheral blood samples were collected from 178 patients of Arab Asian ethnicity (aged ≤17 years) newly diagnosed with AML: 145 samples from Iraq and 33 samples from Jordan. Direct DNA sequencing was performed on six genes including RUNX1 gene (exons 3-8). RESULTS: RUNX1 point mutations were identified in 10 (5.6%) of 178 patients. One patient possessed biallelic mutations of RUNX1 gene. C-terminal area was the predominant site of RUNX1 mutations (eight in C-terminal and two in N-terminal). Patients with RUNX1 mutations were significantly older than those with wild-type of the gene. Additionally, AML M0 subtype was more frequently found in patients with RUNX1 mutations. Both RUNX1 mutations and RAS mutations were identified in 4 of 10 children. Three patients with RUNX1 mutation had FLT3-ITD. On the other hand, 36 (21.4%) and 25 (14.9%) of 168 patients with wild-type of the gene had a RAS mutation and FLT3-ITD, respectively. Eight of 10 patients with RUNX1 mutations died of hematological relapse. CONCLUSION: The incidence of RUNX1 mutations in Arab Asian children and adolescents with AML was 5.6%. Further studies are required to clarify whether RAS mutations contribute to the development of pediatric AML associated with RUNX1 mutations.

Hodgkin Lymphoma in Children: A 16-year Experience at the Children's Welfare Teaching Hospital of Baghdad, Iraq.

Background: Childhood Hodgkin lymphoma (HL) is an eminently curable disease. Good outcomes can be achieved even in resource-limited settings, and the focus is increasingly on limiting long-term toxicity. Contemporary treatment incorporates a risk-stratified, response-adapted approach using multiagent chemotherapy with/without low-dose radiotherapy. Many developing countries continue to use ABVD-based regimens due to limited acute toxicity, cost, and ease of delivery. Objective: We herein report the outcomes of childhood HL diagnosed and treated in an Iraqi single centre over 16 years. Methods: Children ≤14 years old with biopsy-proven HL were enrolled. Most patients received ABVD chemotherapy or COPP/ABV when Dacarbazine was unavailable. Radiotherapy was not available. Results: Three hundred-three children were consecutively newly diagnosed with HL; 284 were considered eligible for the retrospective analysis (treatment refusals 9; deaths before therapy 5; initially diagnosed of non-Hodgkin lymphoma 5). ABVD scheme was administered to 184 children (65%), COPP/ABV to 83 (29%), and other schemes to the remaining 17 patients. Complete response (CR) was achieved in 277 (98%); 4 (1.4%) showed disease progression, and 1 had stable disease. Four patients in CR abandoned therapy and were in CR at the time of analysis, 2 died from infection. Relapse occurred in 42 patients (15%). The 15-year OS and EFS are 89.7% and 70.3%, respectively. Conclusion: In this single Centre, over 16 years, almost 90% of children suffering from HL survive, despite the numerous limitations in diagnostic procedures, shortage of chemotherapy, no radiotherapy facilities, absence of effective second-line treatments, and finally, therapy abandonment for social and financial reasons.

Comprehensive global collaboration in the care of 1182 pediatric oncology patients over 12 years: The Iraqi-Italian experience.

BACKGROUND: Iraq's health care system has gradually declined after several decades of wars, terrorism, and UN economic sanctions. The Oncology Unit at Children's Welfare Teaching Hospital (CWTH) in Baghdad was lacking basic facilities and support. To address this shortcoming, a humanitarian and educational partnership was established between CWTH and Sapienza University of Rome (SUR). METHODS: We investigated the outcomes of 80 online and 16 onsite educational sessions and 142 teleconsultation sessions from 2006 to 2014. We also determined the outcomes of pathology reviews by SUR of 1216 tissue specimens submitted by CWTH from 2007 until 2019 for second opinions. The primary outcomes were discordance, concordance, and changes among clinical diagnoses and pathology review findings. The measures included the frequency of teleconsultation and tele-education sessions, the topics discussed in these sessions, and the number of pathology samples requiring second opinions. FINDINGS: A total of 500 cases were discussed via teleconsultations during the study period. The median patient age was 7 years (range, 24 days to 16·4 years), and the cases comprised 79 benign tumors, 299 leukemias, 120 lymphomas, and 97 solid tumors. The teleconsultation sessions yielded 27 diagnostic changes, 123 confirmed diagnoses, and 13 equivocal impacts. The pathology reviews by SUR were concordant for 996 (81·9%) cases, discordant for 186 (15·3%), and inconclusive for 34 (2·8%). The major cause of discordance was inadequate immunohistochemical staining. The percentage of discordance markedly decreased over time (from 40% to 10%). The cause of the improvement is multifactorial: training of two CWTH pathologists at SUR, better immunohistochemical staining, and the ongoing clinical and pathologic telemedicine activities. The partnership yielded 12 publications, six posters, and three oral presentations by CWTH investigators. INTERPRETATION: The exchange of knowledge and expertise across continental boundaries meaningfully improved the diagnoses and management of pediatric cancer at CWTH.

Genetic evaluation of childhood acute lymphoblastic leukemia in Iraq using FTA cards.

BACKGROUND: Genetic examination of childhood leukemia has not been available in Iraq. We here report the frequency of TEL-AML1, E2A-PBX1, MLL-AF4, and BCR-ABL chimeric transcripts in 264 Iraqi children newly diagnosed with acute lymphoblastic leukemia (ALL), using FTA cards impregnated with bone marrow aspirate or whole blood. PATIENTS AND METHODS: The diagnosis of ALL was made according to standard French-American-British morphologic criteria. Based on the results of storage temperature and duration, most of the FTA samples were preserved at 4°C for up to 6 weeks in five Iraqi hospitals and then transferred to Japan for molecular analysis. Nested reverse transcription-polymerase chain reaction was adopted for the analysis. RESULTS: TEL-AML1 chimeric transcript product was found in 32 (12.1%) of 264 ALL patients. Eleven (4.2%) patients, 4 (1.5%) patients, and 11 (4.2%) patients had E2A-PBX1 mRNA, MLL-AF4 mRNA, and BCR-ABL mRNA, respectively. One patient had both TEL-AML1 and E2A-PBX1 fusion genes. The incidence of TEL-AML1 in Iraqi ALL children appears to be similar to or slightly higher than those of Jordan (12%) and Kuwait (7%). The prevalence and clinical findings of ALL patients with either E2A-PBX1 or BCR-ABL were comparable to the data reported elsewhere. CONCLUSION: International collaboration via FTA cards may be helpful to improve diagnosis and management of patients with hematological malignancies in low-income and underdeveloped countries.

Childhood acute promyelocytic leukemia in a pediatric cancer referral center in Baghdad, Iraq. Improved results with ATRA extended consolidation.

Modern treatments have dramatically improved the prognosis of childhood acute promyelocytic leukemia (APL). This progress has not yielded equivalent benefit in developing countries, where biological studies and supportive cares are insufficient and often unavailable. Since 2003, an all-trans retinoic (ATRA)-based, risk-adapted protocol was initiated in Baghdad. Patients were defined: high-risk with WBC ≥10 × 109/L and standard-risk with WBC <10 × 109/L. ATRA was included in induction and maintenance and, from 2010, in consolidation. Of 429 pediatric acute myeloid leukemia (September 2003-August 2019), 118 (27.5%) were APL. Six children died before therapy, 4 refused; 94/108 (87%) achieved a remission; 12 (11%) died early and 2 abandoned. The 5-year overall survival and event-free survival are 61.8% and 55.5% for all patients, 51.7% and 43.6% for first protocol, 68.4% and 63.9% for second one. Baseline WBC count was a risk factor for induction mortality; early hemorrhagic death remains a major cause of failure. ATRA extended consolidation improved results.

Treatment of children with B-cell non-Hodgkin lymphoma in a low-income country.

BACKGROUND: An adapted LMB 96 derived protocol for B-cell non-Hodgkin lymphoma (NHL) was implemented at the pediatric oncology unit of the Children Welfare Teaching Hospital in Baghdad (Iraq) from 2000 to present. The purpose was to evaluate the feasibility and efficacy of this intensive therapeutic regimen in a limited resource country. METHODS: Patients <15 years of age with high grade B-cell NHL were included. A modified LMB 96 regimen was employed with a reduction of cyclophosphamide and methotrexate dosages due to inadequate laboratory facilities and supportive care. RESULTS: Between 2000 and 2005, 261 children with non-lymphoblastic NHL were registered; 239 were eligible for the analysis. Two patients had stage I disease, 20 stage II, 179 stage III, and 38 stage IV. Fifty-two patients (22%) had bulky disease. Twelve children were assigned to therapeutic group A (low risk), 184 to group B (intermediate risk), and 43 to group C (high risk). One hundred and eighty-four patients (77%) had a complete response after the COP pre-phase. Sixty-nine patients (29%) died during treatment. Twenty-nine patients abandoned treatment. At 24 months, the overall survival rate of the entire patient population was 66% (CI 95%: 62.2-70.6) and the event-free survival rate 53.3% (CI 95%: 50.0-56.8). CONCLUSIONS: The treatment schedule proved effective, but the treatment-related mortality due to infections and metabolic complications was very high owing to the limited supportive care available. The high rate of treatment abandonment was also an important cause of failure, especially for children living far away from the hospital.

Treatment of childhood acute lymphoblastic leukemia in Iraq: a 17-year experience from a single center.

We performed a retrospective analysis of 1415 acute lymphoblastic leukemia children diagnosed between January 2000 and December 2016 at Children Welfare Teaching Hospital, Baghdad, Iraq. Patients were divided into three cohorts according to treatment period (2000-2005; 2006-2011; 2012-2016). Treatments were based on modified-UKALL protocols; a steroid-pre-phase was introduced from September 2008. The overall complete remission was 86%, increased from 80% to 91% in the last period. Early deaths occurred in 10%, decreasing to 6%, overtime. Relapses were 23%; toxic deaths and abandonment 8% and 13%, respectively. At a median follow-up of 65.3 months, with abandonment considered as an event, the 5-year overall survival (OS) and event-free survival were 62.2% and 46.3%, statistically influenced by treatment period (5-year OS 62.6%, 59.1%, 66.3%; p=.057, respectively). Though pediatric ALL survival in Iraq is still below that observed in high income countries, survival rates progressively improved. Toxic deaths remain an important cause of failure.

Impact of international collaboration on the prognosis of childhood acute promyelocytic leukemia in Iraq.

The promotion of an operational network between hospitals and medical schools in Iraq and in Western countries is a primary humanitarian objective of international collaboration. As a consequence of a collaborative project between the Al Mansour Hospital for Pediatrics in Baghdad and the Pediatric Unit of Hematology of "La Sapienza" University, in Rome, in October 2003 a specific all-trans-retinoic acid-based protocol was designed in order to offer a modern therapeutic program for the management of Iraqi children with acute promyelocytic leukemia, adapted to the severe local difficulties. The preliminary encouraging results represent a substantial improvement over the earlier experience in childhood acute promyelocytic leukemia in Iraq.