Pediatric hematology and oncology in Iran

Problem of borderline hemoglobin A2 levels in an Iranian population with a high prevalence of α- and β-thalassemia carriers

Background

It is difficult to classify a small fraction of α- and β-thalassemia (α- and β-thal) carriers based on their Hb A2 levels. Here, we report the results of a molecular investigation in a cohort of thalassemia carriers with borderline Hb A2 levels originated from western Iran.

Results

The documents of 5956 α- or β-thal carriers were reviewed. The frequency of individuals with borderline Hb A2 levels in this cohort was 436 (7.32%). A total of 12 different α-thal and 27 different β-thal variants were identified in this study.

Conclusions

Our data showed that individuals with borderline Hb A2 are not uncommon in our population. Moreover, preselection of α- and β-thal carriers with borderline Hb A2 levels based on Hb A2, mean corpuscular volume (MCV), and mean cell hemoglobin (MCH) is not advisable in our population. Therefore, it is necessary to investigate both α- and β-globin genes in cases with borderline Hb A2 levels, especially if the partner is a carrier of β-thal or α0-thal.

In silico prediction of HBD gene variants in the Iranian population

Background

The quantification of hemoglobin A2 (Hb A2; α2δ2) is used as a valuable test to differentiate α- and ß-thal carriers in clinical laboratories. Therefore, the HBD (δ-globin) gene variants could result in reduced levels of Hb A2 and have implications for thalassemia screening programs. The aim of the present study was to predict the consequences of HBD gene variants identified in the Iranome project.

Results

The highest number of variants was in the Persian Gulf Islanders. The variants of p.Gln132Glu (HBD: c.394C>G), p.Gly17Arg (HBD: c.49G>C), p.Thr5Ile (HBD: c.14C>T), and p.Ala28Ser (HBD: c.82G>T) presented damage results in three or more prediction tools. In addition, it seems that the p.Gly30= (HBD: c.90C>T) decreases the use of authentic splice and, instead, creates a new donor splice site (DSS) or leads to the use of a cryptic DSS.

Conclusions

Most of these variants have been associated with a decrease in Hb A2 levels. Due to the high mutational diversity in the HBB gene in the Iranian population and the use of Hb A2 quantification to differentiate α- and ß-thal carriers among Iranian clinical laboratories, some attention should be taken to a possible co-inheritance of HBD gene variants to avoid the misdiagnosis of ß-thal carriers.

Iranian Registry of Clinical Trials two years on and the timing of registrations

The Iranian Registry of Clinical Trials (IRCT) was established as a primary registry on December 4 2008 and has registered over 1350 trials by June 2011. Many researchers are still unaware of the need for registration of trials before recruiting the first patient and the proportion of retrospectively registered trials is likely to grow until this awareness increases. We sought to investigate the timing of the registrations in IRCT and to explore strategies to overcome this. We used all data in the IRCT database and extracted the date of registration, as well as the dates for the start and the end of recruitment. We categorized trials into 4 groups: those registered before the start of patient enrolment, within 30 days of enrolment, after 30 days but before the end of recruitment, and after the end of recruitment. The proportion of trials in each category was calculated by calendar year. The number of registered trials increased from 26 in the 3 months leading to 2009 to 181 in 2009, 772 in 2010 and 376 in the first 5 months of 2011 (estimate by end of year = 947). The proportions of trials registered after the end of patient recruitment were 55%, 58% and 62% in 2009, 2010 and 2011 respectively. On average, 6.4% of trials were registered within 30 days from the start of patient recruitment and 27% in the time between then and the end of recruitment. The rapid increase in the number of registered trials is an indication of strong implementation of the registration policy. This comes partly at the expense of an increased proportion of retrospective registrations. While this may be understandable at the beginning, it is clearly not acceptable and measures should be adopted to increase the proportion of prospectively registered trials and to make trial registration an integral part of the research culture.

Childhood cancer in Iran

This study tries to define the incidence, survival, and risk factors of childhood cancer in Iran. A literature review on published articles was conducted by using different search engine from November 1974 to October 2008. The incidence rate of childhood cancer in Iran was 48 to 112 and 51 to 144 per million among girls and boys in multi geographical settings, respectively. The most common cancer in children from 0 to 14 years old were leukemia (incidence rate=8 to 62/million), lymphoma (3 to 23), and central nervous system tumors (3 to 22). The mortality rate of childhood cancers was 42 and 49 per million among girls and boys, respectively in 2004. A positive association between ABO blood groups, family history of cancer, drug usage during pregnancy, fathers' job, history of radiation, and parental smoking habit were found with childhood leukemia. It is essential that the effect of geographical differences on childhood cancer incidence rates and high mortality rate to be investigated in future studies.

Successful ambulatory treatment of Hodgkin's disease in Iranian children based on German-Austrian DAL-HD 85-90: single institutional results

BACKGROUND

Hodgkin's disease (HD) accounts for 7.5% of childhood malignancies in Iran. In order to minimize chemotherapy toxicity and avoid eventual hospitalization and psychological and financial burdens we have applied since 1988, for the first time in Iran, a treatment regimen based on subsequently revised DAL-HD 85-90 and later GPOH-HD 95 protocols.

PATIENTS AND METHODS

During the period 1988-2004, 40 children with HD received DAL/GPOH-HD-adapted treatment; 25 males (62.5%) and 15 females (37.5%) (male/female ratio 1.7; age 4-14 years, mean 8.8). Clinical evaluation and staging was performed in all patients. Constitutional symptoms: 24 patients were asymptomatic (A; 60%) and 16 had constitutional complaints (B; 40%). Staging was as follows: stage I; seven (17.5%); II, 11 (27.5%); III, 11 (27.5%); and IV, 11 (27.5%). Histopathology: 22 patients had mixed cellularity (MC; 55%), 13 nodular sclerosis (32.5%), four lymphocyte predominance (LP; 10%) and one patient lymphocyte depletion (2.5%). Stage IA and IIA patients (n = 15) received either OPA x2 (vincristine, prednisolone, doxorubicin) or OPPA x2 or OPEA x2 (vincristine, prednisolone, procarbazine and doxorubicin), the latter receiving etoposide instead of procarbazine, and applied to males. Stages IIB, IIIA/B and IV received OPPA x2, followed by CO(P)P x4 (cyclophosphamide, vincristine, prednisolone in alternate courses and procarbazine). Twenty nine patients (72.5%) received radiotherapy (20-25 Gy); four to the involved field (stage I), 25 to the upper mantel (stage II and also III with either residual or mediastinal mass) and three additionally to spleen and para-aortic lymph nodes. Eleven patients received only chemotherapy.

RESULTS

All patients achieved complete remission (CR). Relapse occurred in eight patients (20%); seven stage IV (MC) and one stage IA (LP) with progression to IIIB. Salvage chemotherapy consisted of MOPP/ABVD hybrid; six patients achieved a second sustained remission and three patients died: two due to relapse and progressive disease and the third one in CR, owing to thrombocytopenic hemorrhage and foudroyant pneumonia. The achieved overall and event-free survival was 88.1% and 75.4%, respectively. Aside from minor acute toxicities, three patients demonstrated azoospermia at the age of 18 years and one of these patients suffered non-Hodgkin lymphoma as a second malignancy. HD occurred as a second malignancy in two patients with acute lymphoblastic leukemia. Both received appropriate treatment and are over 10 years in CR.

CONCLUSIONS

The DAL/GPOH-HD-based treatment approach proved to achieve long-term sustained cure even in children with advanced HD disease. The essentially outpatient diagnosis and treatment modus did not compromise the disease outcome, and was well tolerated and accepted by the patients and their parents. The employed drugs are easily available and affordable. This treatment approach is suitable for ambulatory use in developing countries. However, male infertility remains the major obstacle to procarbazine and cyclophosphamide use.