Incidence, risk factors and outcomes of malignancies after kidney transplantation in Singapore: a 12-year experience

INTRODUCTION@#Data on malignancy after kidney transplantation (KTX) is limited in our region, leading to challenges in the care of renal allograft recipients. We aimed to examine the epidemiology, risk factors and outcomes of post-KTX patients.@*METHODS@#A retrospective cohort study was conducted of 491 patients who underwent KTX from 1 January 2000 to 31 December 2011. Data linkage analysis was done between our centre and the National Registry of Diseases Office to determine the standardised incidence ratio (SIR), standardised mortality ratio (SMR) and risk factors for malignancy after KTX.@*RESULTS@#31 patients (61.3% male) developed malignancy during this period, and their median age at diagnosis was 50 (range 18-65) years. Median time to malignancy diagnosis was 2.6 (range 0.3-7.9) years, with cumulative incidence of 1%, 4% and 10% at one, five and ten years, respectively. The commonest malignancy type was lymphoma, followed by kidney cancer, colorectal cancer and malignancy of the male genital organs. Multivariate analysis identified cyclosporine use as an independent risk factor for malignancy. Compared to the general population, KTX recipients had higher malignancy and mortality rates after malignancy diagnosis (SIR 3.36; SMR 9.45). Survival rates for KTX recipients with malignancy versus those without malignancy were 100%, 93% and 64% versus 97%, 93% and 83% at one, five and ten years, respectively.@*CONCLUSION@#KTX was associated with higher mortality and incidence of malignancy. Newer immunosuppressive agents and induction therapies were not found to be risk factors for malignancy, possibly due to our relatively small sample size.

Selection and Short-Term Outcomes of Living Kidney Donors in Singapore - An Analysis of the Donor Care Registry

<p><b>INTRODUCTION</b>Transplant rates in Singapore have been falling and there is limited information on baseline characteristics and clinical outcomes of living kidney donors nationally. This study aimed to determine the safety of living kidney donor transplant in Singapore by exploring the proportion of donors that meets international selection guidelines and describing short-term clinical outcomes.</p><p><b>MATERIALS AND METHODS</b>We analysed 472 donors who underwent nephrectomies from 1 January 2010 to 31 December 2014 from the Donor Care Registry. We described donor characteristics against 5 international guidelines and measured post-nephrectomy outcomes in 150 local donors for up to 24 months. A multivariate analysis was performed to determine the baseline variables associated with poorer outcomes.</p><p><b>RESULTS</b>There were more foreign than local donors, with differences in gender and hospital types. Selection was generally aligned with international recommendations although 3.0% (using the Chronic Kidney Disease Epidemiology [CKD-EPI] equation) to 8.5% (using radionuclide and creatinine clearance methods) of donors had inappropriate baseline estimated glomerular filtration rates (eGFR) forage. Post-procedure, many foreign donors were lost to follow-up. Over 24 months, eGFR decreased by 33.8% from baseline before recovering gradually to 29.6%. During this period, only 2 donors were admitted for renal or urological conditions and there were no cases of end-stage renal failure or deaths. A lower baseline eGFR (HR: 1.05; 95% Cl, 1.02 to 1.09) and older age (HR: 1.04; 95% Cl, 1.00 to 1.08) were associated with a post-nephrectomy eGFR of less than 60 mL/kg/1.73 m.</p><p><b>CONCLUSION</b>Kidney donation is safe in Singapore. Donor selection is in keeping with international guidelines and short-term outcomes are comparable to other cohorts.</p>

Evaluation of the National Cervical Cancer Screening Programme in Singapore

<p><b>INTRODUCTION</b>A retrospective observational study was performed to evaluate the effectiveness of CervicalScreen Singapore (CSS), a National Cervical Cancer Screening Programme.</p><p><b>METHODS</b>National trends on incidence, mortality of cervical cancer and carcinoma in situ of the cervix before and after the launch of CSS were examined. Linear regression was used to calculate the average annual percentage change in age-standardised incidence and mortality rates. We also examined the operational measures of CSS, such as the women who joined the CSS programme and the diagnostic accuracy of Pap smears. The study was confined to women who consented to join CSS at government-funded polyclinics.</p><p><b>RESULTS</b>Nationally, there was a greater decline in the age-standardised incidence and mortality rates in the period 2004-2008 as compared to the period 1987-2003. Under CSS, a total of 99,759 Pap smears were performed on 81,087 women in the period 2004-2008. However, the number of first screens decreased from 18,434 in 2004 to 11,624 in 2008. Among women aged 25-69 years who had their first Pap smear screening and who were recommended for routine rescreen in three years, 10% had a subsequent rescreen within three years. Overall, the CSS programme was able to detect 0.37 invasive cancers per 1,000 screens in women aged 25-69 years.</p><p><b>CONCLUSION</b>The CSS programme has contributed to a decline in the mortality and incidence of cervical cancer in Singapore. However, the challenges of increasing the screening uptake among eligible women need to be addressed.</p>

Cancer among end-stage renal disease patients on dialysis

<p><b>INTRODUCTION</b>The aim of this study is to investigate the risk of cancer among end-stage renal disease (ESRD) patients on dialysis in Singapore.</p><p><b>MATERIALS AND METHODS</b>The study looks at a retrospective cohort of 5505 ESRD patients who had received dialysis between 1998 and 2007. The cancer risk of these patients would be compared against the risk of the general population.</p><p><b>RESULTS</b>During a median follow-up time of 3.9 years, 267 (4.9%) dialysis patients developed cancer. The risk of cancer (excluding non-melanoma skin cancer) is 1.66 times higher in dialysis patients than the general population, and is highest at age less than 35 years old and at first year after dialysis. Cancer risk was found to be significantly higher among Chinese dialysis patients, followed by Malays, compared to the general population. The 3 sites with highest elevated cancer risks among dialysis patients compared to the general population are kidney, tongue and multiple myeloma.</p><p><b>CONCLUSION</b>The finding of elevated cancer risk among younger dialysis patients is similar to other international studies. High cancer risks among specific cancer sites were also consistent with other studies. In view of the lack of screening procedures for these cancers and shortened expected survival of ESRD patients, cancer screening of ESRD patients should be individualised and based on a reasonable life expectancy and transplant candidacy, keeping in mind the competing risk of cardiovascular mortality.</p>

Prevalence of adolescent idiopathic scoliosis among female school children in Singapore

<p><b>INTRODUCTION</b>Screening for scoliosis started in Singapore schools in 1982 and is currently being done for both boys and girls, as part of the annual school-based health screening programme in all primary and secondary schools. The screening levels in the current protocol were based on the 1997 prevalence study by Wong et al. In the study, it appeared that there was a significant increase in prevalence rates between 9- and 11-year-old girls (i.e. between Primary 4 and Primary 6) but there was no data on the prevalence rates of scoliosis in 10-year-old girls (Primary 5) and in 12-year-old girls (Secondary 1). In order to decide on whether to make changes to the screening levels, a review was conducted to determine the prevalence of scoliosis among the 10-year-old girls (in Primary 5) and 12-year-old girls (in Secondary 1).</p><p><b>MATERIALS AND METHODS</b>A total of 93,626 female students, aged between 9 and 13 years old were screened. The study covered all of the 183 primary schools and only 83 of the 165 secondary schools due to a disruption of health screening in schools during the outbreak of SARS (severe acute respiratory syndrome). In mid-2003, schools in Singapore were closed because Singapore was one of the countries affected by SARS. Scoliosis screening was done for all female students in the Primary 4, 5 and 6 levels as well as in the Secondary 1 and 2 levels. Male students were routinely screened for scoliosis in the Primary 6 and Secondary 2 levels. Scoliosis screening was done by measuring the angle of trunk rotation (ATR) using a scoliometer. All students with ATR >or=5 degrees were referred to the Student Health Centre (SHC) where second-tier screening was done. At SHC, if ATR >or=5 degrees , postero-anterior radiograph of the spine was done. Of the 3186 female students in the primary level, aged between 9 and 13 years old who were referred to SHC for the second-tier screening, 2438 attended, and for secondary students aged between 12 and 13 years old, 1587 out of 1720 students attended.</p><p><b>RESULTS</b>The prevalence rates of idiopathic adolescent scoliosis for the 9- to 13-year-old female students were 0.27%, 0.64%, 1.58%, 2.22% and 2.49%, respectively, which showed an increasing trend in the prevalence rates with increasing age. There was a significant increase in the prevalence rates of adolescent idiopathic scoliosis (AIS) in the 10- to 11-year-old females compared to the 9-year-old females (OR, 1.7; 95% CI, 1.1-2.4; P = 0.010). There was also a significant increase in the prevalence rates in the 12- to 13-year-old females (OR, 2.2; 95% CI, 1.4-3.3; P = 0.001).</p><p><b>CONCLUSIONS</b>The study showed a significant increase in the prevalence rates of scoliosis in the 10- to 11-year-old female students and again a significant increase in the prevalence rates in the 12- to 13-year-old female students. Since the prevalence rate for the 9-year-old females was quite low (0.27%), and there was a significant increase in the prevalence rates in the 10- to 11-year-old and 12- to 13-year-old females, it was recommended that screening for females be performed every year commencing at 10 years old (Primary 5) until 13 years old (Secondary 2).</p>

Trends in long-term cancer survival in Singapore: 1968-2002

<p><b>INTRODUCTION</b>The life expectancy of cancer patients has increased in recent decades due to better diagnostic and screening tools as well as better treatment modalities. Hence, it becomes increasingly important to study trends in long-term cancer patient survival in order to document that medical progress has conveyed benefit at the population level. In this paper, we assessed the long-term survival experience of all incident cancer patients in Singapore.</p><p><b>MATERIALS AND METHODS</b>The study population consisted of patients diagnosed with single primary invasive cancer from 1 January 1968 to 31 December 2002, and passively followed up to 31 December 2005. The data was derived from the Singapore Cancer Registry, which has been in existence since 1968. Relative survival via the period approach was used to provide a more up-to-date estimate by looking at recent cohorts of patients. Sex- and stage-specific survival was compared for each cancer.</p><p><b>RESULTS</b>The overall age-standardised 10-year relative survival ratios for the calendar years of 1998 to 2002 were 30.5% in males and 44.2% in females. A steady improvement in overall long-term cancer survival was observed over the study period. This upward trend in survival was observed in localised tumours and cancers with a favourable prognosis such as breast, cervical and colorectal cancers. In contrast, survival of cancers with poor prognosis such as lung, liver and pancreas remained low.</p><p><b>CONCLUSIONS</b>Although factors such as changes in diagnostic criteria could influence the trend in survival, we believed that the improvement in survival predominantly reflected real progress in cancer control in Singapore.</p>