Long-term survival for lymphoid neoplasms and national health expenditure (EUROCARE-6): a retrospective, population-based study.

BACKGROUND: Management of lymphoid malignancies requires substantial health system resources. Total national health expenditure might influence population-based lymphoid malignancy survival. We studied the long-term survival of patients with 12 lymphoid malignancy types and examined whether different levels of national health expenditure might explain differences in lymphoid malignancy prognosis between European countries and regions. METHODS: For this observational, retrospective, population-based study, we analysed the EUROCARE-6 dataset of patients aged 15 or older diagnosed between 2001 and 2013 with one of 12 lymphoid malignancies defined according to International Classification of Disease for Oncology (third edition) and WHO classification, and followed up to 2014 (Jan 1, 2001-Dec 31, 2014). Countries were classified according to their mean total national health expenditure quartile in 2001-13. For each lymphoid malignancy, 5-year and 10-year age-standardised relative survival (ASRS) was calculated using the period approach. Generalised linear models indicated the effects of age at diagnosis, gender, and total national health expenditure on the relative excess risk of death (RER). FINDINGS: 82 cancer registries (61 regional and 21 national) from 27 European countries provided data eligible for 10-year survival estimates comprising 890 730 lymphoid malignancy cases diagnosed in 2001-13. Median follow-up time was 13 years (IQR 13-14). Of the 12 lymphoid malignancies, the 10-year ASRS in Europe was highest for hairy cell leukaemia (82·6% [95% CI 78·9-86·5) and Hodgkin lymphoma (79·3% [78·6-79·9]) and lowest for plasma cell neoplasms (29·5% [28·9-30·0]). RER increased with age at diagnosis, particularly from 55-64 years to 75 years or older, for all lymphoid malignancies. Women had higher ASRS than men for all lymphoid malignancies, except for precursor B, T, or natural killer cell, or not-otherwise specified lymphoblastic lymphoma or leukaemia. 10-year ASRS for each lymphoid malignancy was higher (and the RER lower) in countries in the highest national health expenditure quartile than in countries in the lowest quartile, with a decreasing pattern through quartiles for many lymphoid malignancies. 10-year ASRS for non-Hodgkin lymphoma, the most representative class for lymphoid malignancies based on the number of incident cases, was 59·3% (95% CI 58·7-60·0) in the first quartile, 57·6% (55·2-58·7) in the second quartile, 55·4% (54·3-56·5) in the third quartile, and 44·7% (43·6-45·8) in the fourth quartile; with reference to the European mean, the RER was 0·80 (95% CI 0·79-0·82) in the first, 0·91 (0·90-0·93) in the second, 0·94 (0·92-0·96) in the third, and 1·45 (1·42-1·48) in the fourth quartiles. INTERPRETATION: Total national health expenditure is associated with geographical inequalities in lymphoid malignancy prognosis. Policy decisions on allocating economic resources and implementing evidence-based models of care are needed to reduce these differences. FUNDING: Italian Ministry of Health, European Commission, Estonian Research Council.

Identifying classes of the pain, fatigue, and depression symptom cluster in long-term prostate cancer survivors-results from the multi-regional Prostate Cancer Survivorship Study in Switzerland (PROCAS).

PURPOSE: Aside from urological and sexual problems, long-term (≥5 years after initial diagnosis) prostate cancer (PC) survivors might suffer from pain, fatigue, and depression. These concurrent symptoms can form a cluster. In this study, we aimed to investigate classes of this symptom cluster in long-term PC survivors, to classify PC survivors accordingly, and to explore associations between classes of this cluster and health-related quality of life (HRQoL). METHODS: Six hundred fifty-three stage T1-T3N0M0 survivors were identified from the Prostate Cancer Survivorship in Switzerland (PROCAS) study. Fatigue was assessed with the EORTC QLQ-FA12, depressive symptoms with the MHI-5, and pain with the EORTC QLQ-C30 questionnaire. Latent class analysis was used to derive cluster classes. Factors associated with the derived classes were determined using multinomial logistic regression analysis. RESULTS: Three classes were identified: class 1 (61.4%) - "low pain, low physical and emotional fatigue, moderate depressive symptoms"; class 2 (15.1%) - "low physical fatigue and pain, moderate emotional fatigue, high depressive symptoms"; class 3 (23.5%) - high scores for all symptoms. Survivors in classes 2 and 3 were more likely to be physically inactive, report a history of depression or some other specific comorbidity, be treated with radiation therapy, and have worse HRQoL outcomes compared to class 1. CONCLUSION: Three distinct classes of the pain, fatigue, and depression cluster were identified, which are associated with treatment, comorbidities, lifestyle factors, and HRQoL outcomes. Improving classification of PC survivors according to severity of multiple symptoms could assist in developing interventions tailored to survivors' needs.

Correction to: Spatial and temporal distribution of carbon dioxide gas using GOSAT data over IRAN.

The original version of this article unfortunately contained an error in the affiliation section.

Spatial and temporal distribution of carbon dioxide gas using GOSAT data over IRAN.

CO2 concentration (XCO2) shows the spatial and temporal variation in Iran. The major purpose of this investigation is the assessment of the spatial distribution of carbon dioxide concentration in the different seasons of 2013 based on the Thermal And Near Infrared Sensor for Carbon Observation-Fourier Transform Spectrometer (TANSO-FTS) level 2 GOSAT data by implementing the ordinary kriging (OK) method. In this study, the Land Surface Temperature (LST), Normalized Difference Vegetation Index (NDVI) data from the MODerate resolution Imaging Spectroradiometer (MODIS), and metrological parameters (temperature and precipitation) were used for the analysis of the spatial distribution of CO2 over Iran in 2013. The spatial distribution maps of XCO2 show the highest concentration of this gas in the south and south-east and the lowest concentration in the north and north-west. These results indicate that the concentration of carbon dioxide decreased with the increase of LST and temperature and a decrease of NDVI and humidity in the study area. Therefore, the existence of vegetation has an effective role in capturing carbon from the atmosphere by photosynthesis phenomena, and sustainable land management can be effective for carbon absorption from the atmosphere and mitigation of climate change in arid and semi-arid regions.

Multi-item multiperiodic inventory control problem with variable demand and discounts: a particle swarm optimization algorithm.

A multi-item multiperiod inventory control model is developed for known-deterministic variable demands under limited available budget. Assuming the order quantity is more than the shortage quantity in each period, the shortage in combination of backorder and lost sale is considered. The orders are placed in batch sizes and the decision variables are assumed integer. Moreover, all unit discounts for a number of products and incremental quantity discount for some other items are considered. While the objectives are to minimize both the total inventory cost and the required storage space, the model is formulated into a fuzzy multicriteria decision making (FMCDM) framework and is shown to be a mixed integer nonlinear programming type. In order to solve the model, a multiobjective particle swarm optimization (MOPSO) approach is applied. A set of compromise solution including optimum and near optimum ones via MOPSO has been derived for some numerical illustration, where the results are compared with those obtained using a weighting approach. To assess the efficiency of the proposed MOPSO, the model is solved using multi-objective genetic algorithm (MOGA) as well. A large number of numerical examples are generated at the end, where graphical and statistical approaches show more efficiency of MOPSO compared with MOGA.

A mobile application for postoperative education of caregivers of children with congenital hypospadias: Requirement analysis.

Background and Aims: Hypospadias, a congenital anomaly, can have long-term effects on sexual, urinary, and reproductive functions, making proper postoperative care essential for desirable outcomes, which could be facilitated through a mobile application for diseases with long-term complications. The aim of this study was to investigate the data and functional requirements or minimum data set of a postoperative education mobile application for caregivers of children with hypospadias. Methods: A literature review of papers published until April 2023 using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was conducted to determine the data and functional requirements of a mobile application that provides postoperative education to caregivers of children with congenital hypospadias. Based on the results, a questionnaire was prepared, and its content validity and reliability were evaluated by CVI and CVR. Additionally, data was examined by 30 residents, specialists, and subspecialists in pediatric surgery using the Delphi approach. Results: The study identified 28 data elements in three main categories: demographic data, clinical data, and application function. Functional requirements of the mobile application were suggested for use in designing the application. Also, the most critical data elements included the definition of disease, the importance of treatment, surgical preparation, bandage, hygiene, symptoms and infection, bleeding, and emergency condition. Conclusion: The study will pave the way for developing postoperative educational applications for caregivers of children with congenital hypospadias. M-Health app developers and clinician specialists can utilize these findings to design practical applications that assist caregivers in managing the care of hypospadias patients.

Survival of European adolescents and young adults diagnosed with cancer in 2010-2014.

BACKGROUND: We used the comprehensive definition of AYA (age 15 to 39 years) to update 5-year relative survival (RS) estimates for AYAs in Europe and across countries and to evaluate improvements in survival over time. METHODS: We used data from EUROCARE-6. We analysed 700,000 AYAs with cancer diagnosed in 2000-2013 (follow-up to 2014). We focused the analyses on the 12 most common cancers in AYA. We used period analysis to estimate 5-year RS in Europe and 5-year RS differences in 29 countries (2010-2014 period estimate) and over time (2004-06 vs. 2010-14 period estimates). FINDINGS: 5-year RS for all AYA tumours was 84%, ranging from 70% to 90% for most of the 12 tumours analysed. The exceptions were acute lymphoblastic leukaemia, acute myeloid leukaemia, and central nervous system tumours, presenting survival of 59%, 61%, and 62%, respectively. Differences in survival were observed among European countries for all cancers, except thyroid cancers and ovarian germ-cell tumours. Survival improved over time for most cancers in the 15- to 39-year-old age group, but for fewer cancers in adolescents and 20- to 29-year-olds. INTERPRETATION: This is the most comprehensive study to report the survival of 12 cancers in AYAs in 29 European countries. We showed variability in survival among countries most likely due to differences in stage at diagnosis, access to treatment, and lack of referral to expert centres. Survival has improved especially for haematological cancers. Further efforts are needed to improve survival for other cancers as well, especially in adolescents.

Prostate cancer incidence and survival in immigrants to Sweden.

PURPOSE: The large international variation in the incidence of prostate cancer (PC) is well known but the underlying reasons are not understood. We want to compare PC incidence and survival among immigrants to Sweden in order to explain the international differences. METHODS: Cancer data were obtained from the Swedish Cancer Registry. Standardized incidence ratios (SIRs) were calculated for PC in first-degree immigrants by country of birth. The immigrants were classified into four groups by SIR and area of origin. Survival in PC was assessed by hazard ratio (HR) in the four groups. In some analyses, clinical stage of PC was assessed by the tumor, node, and metastasis classification. RESULTS: The SIR was 0.47 (95% confidence interval 0.43-0.51) for immigrants with the lowest risk, constituting men from Turkey, Middle East, Asia, and Chile. The HR was 0.60 (0.45-0.81) for these men and it was 0.49 if they had stayed 20+ years in Sweden. The SIR in screening detected PC, T1c, was 0.55. Among these men, screening detected PC constituted 34.5% of all PC, compared to 29.0% among Swedes (p = 0.10). CONCLUSIONS: The results showed that the non-European immigrants, of mainly Middle East, Asian, and Chilean origin, with the lowest risk of PC, also had the most favorable survival in PC. As the available clinical features of PC at diagnosis or the distribution of known risk factors could not explain the differences, a likely biological mechanism through a favorable androgenic hormonal host environment is suggested as an explanation of the observed effects.

Ethnic differences in breast cancer risk and survival: a study on immigrants in Sweden.

BACKGROUND: There are large geographic differences in breast cancer risk but whether survival differs between low- and high-risk groups is less well-established. As the survival of cancer depends on the level of healthcare and awareness of disease risks, subtle differences in cancer biology cannot be revealed in international comparisons. Instead, comparison of diverse immigrant groups in a country of uniformly accessible healthcare system should enable conclusions to be made about ethnic determinants of cancer risk and survival. MATERIAL AND METHODS: The Swedish Family-Cancer Database was used to calculate standardized incidence (SIRs) and hazard ratios (HRs) of death from female breast cancer in 12 505 and 137 547 patients diagnosed with breast cancer among immigrants and Swedes, respectively. The ratios were adjusted for age, period, region, parity, and age at first childbirth. Ordinal logistic regression analysis was used to estimate odds ratios (ORs) for the clinical TNM classes. The analyses were stratified by menopausal status and histology. Results. Turks, Southeast Asians, and Chileans had the lowest breast cancer risk (SIR = 0.44; 95% CI 0.37-0.51) and Iraqis the highest risk (1.19; 1.05-1.35), mainly due to premenopausal cancer (1.51; 1.27-1.78). The HRs for all breast cancers were between 0.98 (0.81-1.18) (low-risk Europeans) and 1.24 (0.94-1.63) (lowest-risk non-Europeans), but were not significant. No differences in survival of ductal carcinoma between immigrants and Swedes were found, while low-risk non-Europeans had a HR of 2.88 (1.37-6.08) for lobular carcinoma. Low-risk non-Europeans were diagnosed in a higher T-class (OR = 1.87; 1.21-2.87) than Swedes. CONCLUSION: We did not find any evidence that ethnic differences in breast cancer risk substantially affect the survival. The observed poor survival of some low-risk immigrants in lobular carcinoma may be related to treatment. The tendency of low-risk immigrants to present with higher T-class compared to Swedes may depend on their lower participation in the mammography screening program.

Morbidity and mortality in gynecological cancers among first- and second-generation immigrants in Sweden.

We studied the effect of new environment on the risk in and mortality of gynecological cancers in first- and second-generation immigrants in Sweden. We used the nationwide Swedish Family-Cancer Database to calculate standardized incidence/mortality ratios (SIRs/SMRs) of cervical, endometrial and ovarian cancers among immigrants in comparison to the native Swedes. Risk of cervical cancer increased among first-generation immigrants with Danish (SIR = 1.64), Norwegian (1.33), former Yugoslavian (1.21) and East European (1.35) origins, whereas this risk decreased among Finns (0.88) and Asians (SIRs varies from 0.11 in Iranians to 0.54 in East Asians). Risk of endometrial (SIRs varies from 0.28 in Africans to 0.86 in Finns) and ovarian (SIRs varies from 0.23 in Chileans to 0.82 in Finns) cancers decreased in first-generation immigrants. The overall gynecological cancer risk for the second-generation immigrants, independent of the birth region, was almost similar to that obtained for the first generations. The birth region-specific SMRs of gynecological cancers in first- and second-generation immigrants co-varied with the SIRs. Risk of gynecological cancers among the first-generation immigrants is similar to that in their original countries, except for cervical cancer among Africans and endometrial cancer among North Americans and East Europeans. Our findings show that risk and mortality of gynecological cancers observed in the first-generation immigrants remain in the second generation. We conclude that the risk and protective factors of gynecological cancers are preserved upon immigration and through generations, suggesting a role for behavioral factors or familial aggregation in the etiology of these diseases.

Age- and time-dependent changes in cancer incidence among immigrants to Sweden: colorectal, lung, breast and prostate cancers.

To examine the role of gender, age at immigration and length of stay on incidence trends of common cancers, we studied risk of colorectal, lung, breast and prostate cancers in immigrants to Sweden from 1958 to 2008. The nationwide Swedish Family-Cancer Database was used to calculate standardized incidence ratios for common cancers among immigrants compared to Swedes. Immigrants were classified into "high-risk" countries when their risk was increased, into "low-risk" when their risk was decreased and into "other" when their risk was nonsignificant. Among those who immigrated at younger age (<30 years), we found an increasing trend for colorectal cancer risk in low-risk men and high-risk women. Among those who immigrated at older age (≥ 30 years), a decreasing lung cancer risk in high-risk men and an increasing breast cancer risk in low-risk women were observed. The increasing trend of prostate cancer risk was independent of age at immigration. The risk trends for "other" immigrants were between the risks of low- and high-risk countries. The gender-specific shifts in cancer risks in immigrants toward the risk in natives indicate a major role of sex, age at immigration and environmental exposures in colorectal and lung cancers risks. In contrast, the unchanged trend of breast cancer among those who immigrated at younger ages and an increasing trend for those who migrated at older ages may suggest a limited effect for environmental exposures, especially at younger age. Our study points out a role of age at immigration on the risk trend of cancer.

Does the risk of stomach cancer remain among second-generation immigrants in Sweden?

The observed increased risks of noncardia stomach cancer among foreign-born second-generation immigrants compared to the Swedes suggest that these immigrants were infected by Helicobacter pylori before immigration.

Risks of papillary and follicular thyroid cancer among immigrants to Sweden.

Previous studies have indicated that ionizing radiation, particularly during childhood, is the main established risk factor for thyroid cancer. History of benign nodules/adenoma, goiter, iodine deficiency or high-iodine intake might be other associated factors. We wanted to define the histology-specific thyroid cancer risk in the first-generation immigrants to Sweden. We used the 2010 update of the nation-wide Swedish Family-Cancer Database (>12 million individuals; 1.8 million immigrants; histology code in force since 1958) to calculate standardized incidence ratios (SIRs) for histology-specific thyroid cancer among immigrants compared to the native Swedes. The patient series covered 2,604 male and 6,406 female Swedes, and 247 and 863 immigrants. The median age at immigration was 29 years, and the median age at thyroid cancer diagnosis was 46 years. Increased risks for female papillary carcinoma were observed for Finns (SIR = 1.63), former Yugoslavians (2.36), Russians (2.34), other East Europeans (2.14), Turks (3.16), Iranians (2.68), Iraqis (2.77), East and Southeast Asians (2.92), other Asians (1.69) and South Americans (2.23). Male Iranians (2.85), East and Southeast Asians (3.57) and other Asians (2.26) had an increased risk for papillary carcinoma. Only male East and Southeast Asians (2.93) had an increased risk for follicular carcinoma. The data might suggest that immigrant populations in Sweden from areas of low or high-iodine intake are at risk of papillary carcinoma, implicating iodine imbalance as a contributing factor to our findings. The increased risk of thyroid cancer among Asian immigrants may confirm the role of childhood-ionizing radiation on thyroid cancer risk.

Does the breast cancer age at diagnosis differ by ethnicity? A study on immigrants to Sweden.

BACKGROUND: Age-specific incidence rates for breast cancer in low-risk and high-risk ethnic populations differ by age at which the incidence maximum is reached: around 50 years in low-risk populations and over 60 years in high-risk populations. The interpretation of these differences remains unsettled, one line primarily referring to biological differences, the second one to cohort effects of rapidly increasing rates in young populations, and the third one to incomplete registration of cancer in the elderly. METHODS: The nationwide Family-Cancer Database was used to analyze standardized incidence ratios (SIRs) and age at diagnosis of breast cancer in female immigrants to Sweden by their region of origin compared with women native to Sweden matched on birth year and other relevant factors. RESULTS: We showed first that the SIRs for breast cancer were lower in many immigrant groups compared with natives of Sweden; women from Turkey had the lowest SIR of 0.45, followed by those from Chile (0.54) and Southeast Asia (0.57). Women from nine regions showed an earlier mean age at diagnosis than their matched Swedish controls, the largest differences being 5.5 years for women from Turkey, 5.1 years for those from Asian Arab and "Other African" countries, 4.3 years for those from Iran, and 4.0 years for those from Iraq. CONCLUSIONS: The results show that in many immigrant groups, the diagnostic age is earlier (<50 years) than in natives of Sweden (>50 years), suggesting that true biological factors underlie the differences. These factors may explain much of the international variation in breast cancer incidence. Identifying these factors should advance understanding of breast cancer etiology and prevention.

Preventable breast cancer is postmenopausal.

Breast cancer incidence has markedly increased in Western countries for reasons that are not entirely understood. We characterized periodic and age-specific incidence trends of breast cancer in immigrants who migrated from low incidence areas to Sweden. The incidence in immigrants was compared to that in native Swedes and standardized incidence ratios (SIRs) were calculated, based on the Swedish Family-Cancer Database. Age-specific incidence data for low and high incidence populations were obtained from Cancer Incidence in Five Continents IX and NORDCAN. For immigrants from the seven lowest countries/regions 535 breast cancers were identified; the SIRs ranging from 0.45 for Turkish to 0.70 for Greek women. The SIR increased somewhat with the length of stay in Sweden, from 0.55 for stay between 0 and 10 years to 0.59 for a stay of 20+ years. The age-specific incidence curves for these immigrants were superimposable upon the earliest Swedish (year 1960) or Danish (1943) rates. These rates differed from the current Swedish rates by a much lower postmenopausal component. Large incidence differences were also observed between white Californians and immigrants from China and Korea. Our results show that the main difference between high and low incidence areas is in postmenopausal cancer which has increased preferentially during the past century. Immigrants from low risk areas to Sweden show age-specific incidence patterns of Swedes half a century ago. These differences offer opportunities for the identification of factors underlying breast cancer etiology and tools for prevention.

Does immigration play a role in the risk of gastric cancer by site and by histological type? A study of first-generation immigrants in Sweden.

The observed increased risks of gastric cancer among first-generation immigrants compared to those in Swedes suggest the role of childhood environmental exposure in the risk of this disease.

Nasopharyngeal and hypopharyngeal carcinoma risk among immigrants in Sweden.

Environmental exposures, particularly infection with Epstein-Barr virus (EBV) and tobacco, are known risk factors for oral cancer. Studies in migrants may provide valuable insight into the environmental and genetic etiology of cancer. We wanted to define nasopharyngeal and hypopharyngeal carcinoma among immigrants in Sweden. The nationwide Swedish Family-Cancer Database (FCD) was used to calculate standardized incidence ratios (SIRs) for nasopharyngeal and hypopharyngeal carcinomas among the first-generation immigrants compared to the native Swedes. The FCD included 1969 and 691 cases of nasopharyngeal and hypopharyngeal carcinoma in the male and female Swedes and 178 and 65 cases in immigrants, respectively. The median age at diagnosis (years) was 63 among Swedes and 55 among immigrants. The risk of nasopharyngeal carcinoma was significantly higher in male (SIR = 35.6) and female (24.6) Southeast Asians, male (12.4) and female (34.7) North Africans, male (4.9) and female (10.9) Asian Arabs and some other male Asians immigrants (6.2 to 6.7). Among immigrants from European countries, only the men from former Yugoslavian showed an elevated risk (2.7). Hypopharyngeal carcinoma risk was only increased among the male immigrants from the Indian Subcontinent (5.4). Early life infection with EBV in countries of origin and probably a minor contribution by tobacco smoking may be the main environmental exposures influencing nasopharyngeal carcinoma risks among immigrants to Sweden. The high rates of hypopharyngeal carcinoma among Indian immigrants may point to a continued using of smokeless tobacco.

The Swedish Family-Cancer Database 2009: prospects for histology-specific and immigrant studies.

The Swedish Family-Cancer Database comprises a total of 11.8 million individuals covering the Swedish population of the past 100 years. Version VIII of the Database is described in the present article. Cancer cases were retrieved from the Swedish Cancer Registry for the period 1958-2006, including more than 1 million first primary cancers. The number of familial cancers in offspring is 14,000 when a parent was diagnosed with a concordant (same) cancer and the number of concordant siblings was 6,000. From the year 1993 onwards histopathological data according to the SNOMED classification were used, which entails advantages for certain cancers, such as breast cancer. Even though the specific morphological classification only covers a limited number of years, it does cover most familial cancers in the offspring generation. The Database records the country of birth for each subject. A total of 1.79 million individuals were foreign born, Finns and other Scandinavians being the largest immigrant groups. The cancer incidence in the first-generation immigrants was compared to that in native Swedes using standardised incidence ratios (SIRs) to measure relative risk. The SIRs ranged widely between the immigrant groups, from 1.9-fold for myeloma to 25-fold for melanoma. The differences in SIRs were smaller in the second-generation immigrants. The usefulness and the possible applications of the Family-Cancer Database have increased with increasing numbers of cases, and the numerous applications have been described in some 300 publications. Familial cancer studies are in the stimulating interphase of the flourishing disciplines of genetics and epidemiology.

Surveillance of HIV drug resistance transmission in Iran: experience gained from a pilot study.

We performed a pilot surveillance study on transmitted HIV drug resistance (TDR) in Iran, with specimens collected and stored as dried blood spots (DBS). The protease region and relevant positions in the reverse transcriptase region of the pol gene were sequenced to detect mutations known to be associated with resistance to drugs in standard first-line regimens. Seventy-three specimens were collected, with 39 (53%) specimens yielding sequence from both protease and at least part of RT. Specimens were almost exclusively HIV-1 subtype CRF 35_A1D based on pol sequencing. Mutations were restricted to RT, with D67DG and V75AV each seen in a single specimen. An atypical protease inhibitor mutation, I47M, appeared at a resistance-associated position in protease from a single specimen. These preliminary data showed that the rate of transmitted drug resistance in Iran, within the areas sampled, was 5.1% (2/39). However, the small sample size makes this figure only an approximation. Due to the sampling strategy and resulting small sample size, we were unable to accurately calculate TDR rates for individual areas using the WHO HIV drug resistance threshold survey method. Increasing the sample size and improving the yield from DBS would improve the accuracy of drug resistance surveillance and facilitate wider application of this methodology in Iran.

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.