Independent and Synergistic Associations of Aerobic Physical Activity and Resistance Exercise with Nonalcoholic Fatty Liver Disease

Background/Aims@#This study aimed to examine the independent and synergistic association of aerobic physical activity and resistance exercise with nonalcoholic fatty liver disease (NAFLD) using a nationwide representative database. @*Methods@#This was a cross-sectional study using data from the Korea National Health and Nutritional Examination Survey between 2007 and 2010. Multiple logistic regression models were used to examine the independent and synergistic (additive interaction) associations of aerobic physical activity and resistance exercise with NAFLD after adjusting for multiple covariates. @*Results@#The prevalence of NAFLD was 26.2% for men and 17.6% for women. In the fully adjusted multiple logistic regression model to examine the independent association of aerobic physical activity or resistance exercise with NAFLD, the odds ratios for NAFLD were significantly decreased in both men (p=0.03) and women (p<0.01) who had highly active aerobic physical activity. Regarding the frequency of resistance exercise, the odds ratio for NAFLD was decreased in men who did resistance exercise ≥5 days per week (p=0.04), but not in women (p=0.19). How-ever, when investigating the synergistic associations of aerobic physical activity and resistance exercise, the odds ratios for NAFLD significantly decreased when the frequency of both exercises increased together in both men (p for interaction <0.01) and women (p for interaction<0.01). @*Conclusions@#Combining aerobic physical activity and resistance exercise had a synergistic preventive association for NAFLD in Korean men and women.

The association of pancreatic cancer incidence with smoking status and smoking amount in Korean men / 한국역학회지

OBJECTIVES@#Our study examined the dose-response relationship between smoking amounts (pack-years) and the risk of developing pancreatic cancer in Korean men. @*METHODS@#Of 125,743 participants who underwent medical health checkups in 2009, 121,408 were included in the final analysis and observed for the development of pancreatic cancer. We evaluated the associations between smoking amounts and incident pancreatic cancer in 4 groups classified by pack-year amounts. Cox proportional hazards models were used to estimate the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of incident pancreatic cancer by comparing groups 2 (40 pack-year smokers) with group 1 (never smokers). @*RESULTS@#During 527,974.5 person-years of follow-up, 245 incident cases of pancreatic cancer developed between 2009 and 2013. The multivariate-adjusted HRs (95% CIs) for incident pancreatic cancer in groups 2, 3, and 4 were 1.05 (0.76 to 1.45), 1.28 (0.91 to 1.80), and 1.57 (1.00 to 2.46), respectively (p for trend=0.025). The HR (95% CI) of former smokers showed a dose-response relationship in the unadjusted model, but did not show a statistically significant association in the multivariate-adjusted model. The HR (95% CI) of current smokers showed a dose-response relationship in both the unadjusted (p for trend=0.020) and multivariate-adjusted models (p for trend=0.050). @*CONCLUSIONS@#The risk of developing pancreatic cancer was higher in current smokers status than in former smokers among Korean men, indicating that smoking cessation may have a protective effect.

Long-term Oncologic Outcome and Its Relevant Factors in Anal Cancer in Korea: A Nationwide Data Analysis

Purpose@#Anal cancer is a rare disease in Korea, and thus survival analyses are limited by small sample sizes. This study used the Korea Central Cancer Registry (KCCR) for a survival analysis and for assessing characteristics of anal cancer in a large sample of Koreans. @*Methods@#From the KCCR, data on 3,615 patients who were diagnosed and treated for anal cancer from 1993 to 2015 were retrieved. Clinicopathologic variables including age, sex, histological type, and Surveillance Epidemiology and End Results (SEER) stage were reviewed, and a survival analysis was performed according to these variables. @*Results@#The 5-year relative survival rate improved from 39.7% in 1993–1995 to 66.5% in 2011–2015. Squamous cell carcinoma was the most common and showed the highest survival rate. Males and older patients (≥40 years and ≥70 years) showed poor prognoses. @*Conclusion@#The survival rate for anal cancer in Korea has improved steadily over time. The characteristics related to survival were the histological type, sex, and age. These statistics will be fundamental for future Korean anal cancer research.

Incidence and Overall Survival of Biliary Tract Cancers in South Korea from 2006 to 2015: Using the National Health Information Database

BACKGROUND/AIMS: There have been no nationwide studies to investigate the trends in incidence and 5-year survival rates of intra- and extrahepatic bile duct cancers and gall-bladder cancer. Therefore, our study aimed to describe the incidence and 5-year survival rates of biliary tract cancers by subsites in South Korea. METHODS: A total of 86,134 patients with biliary tract cancers were selected from the National Health Information Database. Age-standardized incidence rates and annual percentage changes were calculated. Life-table methods and log-rank tests were used to determine the differences in survival rates. Cox-proportional hazard models were used to estimate the hazard ratio of the patients with biliary tract cancers. RESULTS: The incidence rate of intra-hepatic bile duct cancer decreased by 1.3% annually from 8.8 per 100,000 in 2006 to 7.8 per 100,000 in 2015. Extrahepatic bile duct cancer also showed a decreasing trend by 2.2% per year from 8.7 per 100,000 in 2006 to 6.7 per 100,000 in 2015. Gallbladder cancer showed the greatest decline, with an annual percentage change of 2.8% from 6.3 per 100,000 to 5.2 per 100,000 during the same period. The 5-year survival rates were 30.0% in gallbladder cancer, 27.8% in extrahepatic bile duct cancer, and 15.9% in intra-hepatic bile duct cancer. CONCLUSIONS: The overall incidence rates of intrahepatic and extrahepatic bile duct cancer and gallbladder cancer decreased from 2006 to 2015. Among biliary tract cancers, intrahepatic bile duct cancers exhibited the highest incidence rate and the worst survival rate.

Health Indicators Related to Disease, Death, and Reproduction / 예방의학회지

One of the primary goals of epidemiology is to quantify various aspects of a population’s health, illness, and death status and the determinants (or risk factors) thereof by calculating health indicators that measure the magnitudes of various conditions. There has been some confusion regarding health indicators, with discrepancies in usage among organizations such as the World Health Organization the, Centers for Disease Control and Prevention (CDC), and the CDC of other countries, and the usage of the relevant terminology may vary across papers. Therefore, in this review, we would like to propose appropriate terminological definitions for health indicators based on the most commonly used meanings and/or the terms used by official agencies, in order to bring clarity to this area of confusion. We have used appropriate examples to make each health indicator easy for the reader to understand. We have included practical exercises for some health indicators to help readers understand the underlying concepts.

Health Indicators Related to Disease, Death, and Reproduction / 예방의학회지

One of the primary goals of epidemiology is to quantify various aspects of a population’s health, illness, and death status and the determinants (or risk factors) thereof by calculating health indicators that measure the magnitudes of various conditions. There has been some confusion regarding health indicators, with discrepancies in usage among organizations such as the World Health Organization the, Centers for Disease Control and Prevention (CDC), and the CDC of other countries, and the usage of the relevant terminology may vary across papers. Therefore, in this review, we would like to propose appropriate terminological definitions for health indicators based on the most commonly used meanings and/or the terms used by official agencies, in order to bring clarity to this area of confusion. We have used appropriate examples to make each health indicator easy for the reader to understand. We have included practical exercises for some health indicators to help readers understand the underlying concepts.

Non-Alcoholic Fatty Liver Disease and Its Association with Depression in Korean General Population

BACKGROUND: Recent studies have indicated the significant association between non-alcoholic fatty liver disease (NAFLD) and depression. However, there is ongoing debate on whether the risk for depression is actually related with the presence and severity of NAFLD. Thus, this study was conducted to investigate the association between depression and NAFLD evaluated by diverse modalities. METHODS: A total of 112,797 participants from the Korean general population were enrolled. The study participants were categorized into three groups according to degree of NAFLD evaluated by ultrasonography, fatty liver index (FLI) and fibrosis-4 score (FIB-4). Depression was defined as a score of Center for Epidemiological Studies-Depression (CES-D) ≥ 16, and the odd ratios (ORs) and 95% confidence interval (CI) for depression (adjusted ORs [95% CI]) were assessed by multiple logistic regression analyses. RESULTS: In the unadjusted model, the presence and severity of NAFLD was not significantly associated with depressive symptoms. However, in the fully adjusted model, ORs for depression increased in proportion to the degree of ultrasonographically detected NAFLD (mild fatty liver: 1.14 [1.06–1.22]; and moderate to severe fatty liver: 1.32 [1.17–1.48]). An association was also observed between depression and FLI (30 ≤ FLI < 60: 1.06 [0.98–1.15]; FLI ≥ 60: 1.15 [1.02–1.29]). CONCLUSION: The presence and severity of NAFLD is significantly associated with depressive symptoms. In addition, this association was more distinct after adjusting for covariates including age, gender and insulin resistance. This finding indicates the necessity of further study evaluating the incidental relationship of depression with NAFLD.

Effect of Statin Use on Liver Cancer Mortality Considering Hypercholesterolemia and Obesity in Patients with Non-Cirrhotic Chronic Hepatitis B

Little is known about the benefits of statin use on liver cancer mortality among patients with chronic hepatitis B (CHB) considering hypercholesterolemia and obesity. A nationwide retrospective cohort study was conducted using data from a Health Examination Cohort of the National Health Insurance Service of Korea. Data on CHB patients with no other concurrent liver disease were acquired, and statin use was defined as a cumulative daily dose ≥28. A 3-year landmark analysis was performed to avoid immortal time bias. Patients who started statin therapy within the landmark date were considered statin users. A Cox regression analysis was applied to assess associations between statin use and liver cancer mortality considering hypercholesterolemia and obesity. Among 13063 patients, 193 (1.5%) died of liver cancer during the mean follow-up period of 10.6 years. After adjusting for demographic and metabolic factors, statin use [hazard ratio (HR), 0.17; 95% confidence interval (CI), 0.04–0.70] and hypercholesterolemia (HR, 0.46; 95% CI, 0.24–0.88 for total cholesterol ≥240 mg/dL) were associated with a decreased risk of liver cancer mortality, whereas body mass index (BMI) ≥30 kg/m² was associated with an increased risk of liver cancer mortality (HR, 2.46; 95% CI, 1.20–5.06). This study showed that statin use was associated with decreased liver cancer mortality when adjusting for cholesterol levels and BMI. This study found that hypercholesterolemia was independently associated with decreased liver cancer mortality regardless of statin use.

Nationwide Statistical Analysis of Lymphoid Malignancies in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Regional differences in the incidence of lymphoid malignancies have been reported worldwide, but there has been no large-scale epidemiologic analysis in Korea. The aim of this study was to provide a nationwide population-based statistical analysis of Korean patients with lymphoid malignancies. MATERIALS AND METHODS: The Korea Central Cancer Registry analyzed the incidence and survival of patients with lymphoid malignancies from the Korean National Cancer Incidence Database. Diseases were grouped by clinically relevant categories based on the 2008 World Health Organization classification. RESULTS: Overall 65,948 lymphoid diseases were identified between 1999 and 2012. The incidence of most subtypes increased with age, except for precursor cell neoplasms. Male predominance (male:female ratio=1.28:1) was observed. In 2012, annual age-standardized incidence rates per 100,000 persons of Hodgkin’s lymphoma, mature B-cell neoplasm, mature T/natural killer (NK)–cell neoplasm, and precursor cell neoplasm were 0.46, 6.60, 0.95, and 1.50, respectively, and they increased yearly from 1999. Composite Hodgkin’s and non-Hodgkin’s lymphomas were extremely rare. Survival improvement estimated using 5-year relative survival rate was observed in patients with Hodgkin’s lymphoma (71.1%-83.0%), diffuse large B-cell lymphoma (49.5%-61.5%), plasma cell neoplasms (20.2%-36.9%), and lymphoblastic lymphoma/leukemia (41.5%-56.3%) between 1993 and 2012. However, survival rates of T/NK-cell lymphoma (excluding cutaneous T-cell lymphoma) ranged from 40.5%-43.5% during the study period. Survival rates decreased with age in most subtypes. CONCLUSION: This report presented the subtype-specific statistical analysis of lymphoid malignancies in the Korean population, showing increasing incidences and survival rates in most subtypes.

Second Primary Cancer Risk among Kidney Cancer Patients in Korea: A Population-Based Cohort Study / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Secondary primary cancers (SPCs) commonly arise in patients with renal cell carcinoma (RCC). We designed the present study to estimate the SPC incidence in Korean patients with RCC. MATERIALS AND METHODS: The study cohort was population-based and consisted of 40,347 individuals from the Korean Central Cancer Registry who were diagnosed with primary renal cancer between 1993 and 2013. Standardized incidence ratios (SIRs) for SPCs were estimated for different ages at diagnosis, latencies, diagnostic periods, and treatments. RESULTS: For patients with primary RCC, the risk of developing a SPC was higher than the risk of developing cancer in the general population (SIR, 1.13; 95% confidence interval, 1.08 to 1.18). Most cancer types showed higher incidences in patients with RCC than in the general population. However, the relative incidence of gastric cancer as an SPC varied by age. Gastric cancer incidence was elevated in young patients (< 30 years) with RCC, but reduced in older (≥ 30) patients with RCC. Patients with advanced RCC died prematurely, regardless of SPC development. In contrast, those with early-stage RCC survived for longer periods, although SPC development affected their post-RCC survival. After SPC development, women had better survival than men. CONCLUSION: In Korean patients with primary RCC, the incidence of SPC was 13% higher than the incidence of cancer in the general population. These findings may play important roles in the conduct of follow-up evaluations and education for patients with RCC.

Geographical Variations and Trends in Major Cancer Incidences throughout Korea during 1999-2013 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We aimed to describe the temporal trends and district-level geographical variations in cancer incidences throughout Korea during 1999-2013. MATERIALS AND METHODS: Data were obtained from the Korean National Cancer Incidence Database. We calculated the age-standardized cumulative cancer incidences according to sex and geographical region (metropolitan cities, provinces, and districts) for three 5-year periods (1999-2003, 2004-2008, and 2009-2013). Each quintile interval contained the same number of regions. Disease maps were created to visualize regional differences in the cancer incidences. RESULTS: Substantial differences in cancer incidences were observed according to district and cancer type. The largest variations between geographical regions were found for thyroid cancer among both men and women. There was little variation in the incidences of stomach, colorectal, and lung cancer according to geographical region. Substantially elevated incidences of specific cancers were observed in Jeollanam-do (thyroid); Daejeon (colorectum); Jeollanam-do, Gyeongsangbuk-do, and Chungcheongbuk-do (lung); Seocho-gu, Gangnam-gu and Seongnam, Bundang-gu (breast and prostate); Chungcheong and Gyeongsang provinces (stomach); Ulleung-gun and the southern districts of Gyeongsangnam-do and Jeollanam-do (liver); and along the Nakdonggang River (gallbladder and biliary tract). CONCLUSION: Mapping regional cancer incidences in Korea allowed us to compare the results according to geographical region. Our results may facilitate the development of infrastructure for systematic cancer incidence monitoring, which could promote the planning and implementation of region-specific cancer management programs.

Characteristics and Survival of Korean Patients With Colorectal Cancer Based on Data From the Korea Central Cancer Registry Data

PURPOSE: The incidence of colorectal cancer (CRC) in Korea has increased remarkably during the past few decades. The present study investigated the characteristics and survival of patients with CRC in Korea as a function of time, tumor distribution, stage, sex, and age. METHODS: We retrieved clinical data on 326,712 CRC patients diagnosed between 1996 and 2015 from the Korea Central Cancer Registry. The incidence and the 5-year relative survival rates were compared across time period, tumor distribution, stage, sex, and age group. RESULTS: The percentage of patients with colon cancer increased from 49.5% in 1996–2000 to 66.4% in 2011–2015 while the percentage of patients with rectal cancer decreased from 50.5% to 33.6%. The 5-year relative survival rates for all CRCs improved from 58.7% in 1996–2000 to 75.0% in 2011–2015. For 1996–2000, survival rates were highest for patients with left-sided colon cancers, followed by those with right-sided, transverse, rectal, rectosigmoid cancers. For 2011–2015, the survival rates for patients with left-sided cancers were highest, followed by those with rectosigmoid, rectal, transverse, and right-sided colon cancers. Patients with local and regional, but not distant, SEER (Surveillance, Epidemiology, and End Results) stage tumors experienced significantly increased survival rates for 2006–2010 and 2011–2015. The proportion of CRC patients by age decreased in the order ≥70, 60–69, 50–59, 40–49, ≤39 years whereas survival rates decreased in the order 50–59, 60–69, 40–49, ≤39, ≥70 years. CONCLUSION: Korean CRC has some distinct characteristics and survival patterns in terms of tumor distribution, stage, sex, and age. With time, survival outcomes have improved for both local and regional, but not distant, stage tumors.

Nationwide Trends in the Incidence of Melanoma and Non-melanoma Skin Cancers from 1999 to 2014 in South Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This descriptive study was aimed to examine trends in the incidence of melanoma and nonmelanoma in South Korea. MATERIALS AND METHODS: The nationwide incidence data for melanoma and non-melanoma skin cancer was obtained from the Korea Central Cancer Registry. Age-standardized rates were calculated and analyzed, using a Joinpoint regression model. RESULTS: The incidence of basal cell carcinoma has increased dramatically both in men (average annual percentage change [AAPC], 8.0 [95% confidence interval (CI), 6.0 to 10.1]) and women (AAPC, 9.0 [95% CI, 7.5 to 10.4]). Squamous cell carcinoma has also steadily increased both in men (AAPC, 3.3 [95% CI, 2.6 to 4.0]) and women (AAPC, 6.8 [95% CI, 5.3 to 8.4]). Cutaneous melanoma increased continuously from 1999 to 2014 inwomen (AAPC, 3.5 [95% CI, 2.4 to 4.6]), whilst rapidly increasing in men until 2005 (APC, 7.9 [95% CI, 2.4 to 13.7]) after which no increase has been observed (APC, -0.2 [95% CI, -2.3 to 2.0]). CONCLUSION: The incidence rates of melanoma and non-melanoma skin cancer have increased over the past years, with the exception of melanoma in men. Further studies are required to investigate the reasons for the increased incidence of these skin cancers in South Korea.

The unrealized potential: cohort effects and age-period-cohort analysis / 한국역학회지

This study aims to provide a systematical introduction of age-period-cohort (APC) analysis to South Korean readers who are unfamiliar with this method (we provide an extended version of this study in Korean). As health data in South Korea has substantially accumulated, population-level studies that explore long-term trends of health status and health inequalities and identify macrosocial determinants of the trends are needed. Analyzing long-term trends requires to discern independent effects of age, period, and cohort using APC analysis. Most existing health and aging literature have used cross-sectional or short-term available panel data to identify age or period effects ignoring cohort effects. This under-use of APC analysis may be attributed to the identification (ID) problem caused by the perfect linear dependency across age, period, and cohort. This study explores recently developed three APC models to address the ID problem and adequately estimate the effects of A-P-C: intrinsic estimator-APC models for tabular age by period data; hierarchical cross-classified random effects models for repeated cross-sectional data; and hierarchical APC-growth curve models for accelerated longitudinal panel data. An analytic exemplar for each model was provided. APC analysis may contribute to identifying biological, historical, and socioeconomic determinants in long-term trends of health status and health inequalities as well as examining Korean's aging trajectories and temporal trends of period and cohort effects. For designing effective health policies that improve Korean population's health and reduce health inequalities, it is essential to understand independent effects of the three temporal factors by using the innovative APC models.

Current Trends in the Incidence and Survival Rate of Urological Cancers in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This descriptive study assessed the current trends in the incidence of urological cancers and patient survival in Korea. MATERIALS AND METHODS: In this nationwide retrospective observational study based on the data from the Korea National Cancer Incidence Database (KNCIDB), this study analyzed the age-standardized incidence rates (ASRs) and annual percentage changes (APCs) of kidney, bladder, prostate, testicular, and penile cancers as well as cancer of the renal pelvis and ureter between 1999 and 2012. The relative survival rates (RSRs) were calculated for urological cancer patients diagnosed between 1993 and 2012 from the KNCIDB data. RESULTS: Prostate cancer was diagnosed in 66,812 individuals followed by bladder (41,549) and kidney (36,836) cancers. The overall ASR (18.26 per 100,000) increased with age because of the higher ASRs of bladder and prostate cancers in the elderly. The ASR for kidney cancer was highest in the 40-59-year-old group, whereas testicular cancer occurred most frequently before the age of 40. The incidence of most urological cancers increased (overall APC, 6.39%; p < 0.001), except for penile (APC, –2.01%; p=0.05) and bladder (APC, –0.40%; p=0.25) cancers. The overall survival increased steadily (5-year RSR, 66.4% in 1993-1995 vs. 84.2% in 2008-2012; p < 0.001), particularly for prostate (by 34.10%) and kidney (by 16.30%) cancers, but not for renal pelvis and ureter cancers (–7.20%). CONCLUSION: The most common urological cancer in Korea was prostate cancer followed by bladder and kidney cancers. The incidence of most urological cancers, except for penile and bladder cancers, increased. Survival also increased, particularly for prostate and kidney cancers.

Lung Cancer Epidemiology in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The current study was undertaken to examine the trends in the lung cancer incidence, mortality, and survival after a diagnosis in Korea. MATERIALS AND METHODS: Lung cancer incidence data according to the histologic type and mortality data were obtained from the Korea Central Cancer Registry and the Statistics Korea, respectively. The age-standardized incidence and mortality rates were calculated, and the Joinpoint model and age-period-cohort analyses were used to describe the trends in the rates. The 5-year relative survival rates of lung cancer were also calculated. RESULTS: Although the number of new lung cancer cases increased between 1999 and 2012, the age-standardized incidence rate decreased by 0.9% per year in men, whereas the incidence in women increased by 1.7% per year over the same time. Until 2010, the most common histologic type in men was squamous cell carcinoma, then adenocarcinoma prevailed thereafter. Since 1999, the most frequent histological type in women was adenocarcinoma. The lung cancer mortality started to decrease in 2002, with a more apparent decline for the younger age groups in both men and women. Overall, the 5-year relative survival rates have improved significantly from 11.2% for men and 14.7% for women among patients diagnosed between 1993 and 1997 to 19.3% for men and 28.2% for women among patients diagnosed between 2008 and 2012, respectively. An improvement in survival rate was observed for all major histology groups. CONCLUSION: The epidemiology of lung cancer in Korea has changed over a short time span, with decreasing mortality and improving survival rates. Further study is warranted to determine the cause of these changes.

The unrealized potential: cohort effects and age-period-cohort analysis / 한국역학회지

This study aims to provide a systematical introduction of age-period-cohort (APC) analysis to South Korean readers who are unfamiliar with this method (we provide an extended version of this study in Korean). As health data in South Korea has substantially accumulated, population-level studies that explore long-term trends of health status and health inequalities and identify macrosocial determinants of the trends are needed. Analyzing long-term trends requires to discern independent effects of age, period, and cohort using APC analysis. Most existing health and aging literature have used cross-sectional or short-term available panel data to identify age or period effects ignoring cohort effects. This under-use of APC analysis may be attributed to the identification (ID) problem caused by the perfect linear dependency across age, period, and cohort. This study explores recently developed three APC models to address the ID problem and adequately estimate the effects of A-P-C: intrinsic estimator-APC models for tabular age by period data; hierarchical cross-classified random effects models for repeated cross-sectional data; and hierarchical APC-growth curve models for accelerated longitudinal panel data. An analytic exemplar for each model was provided. APC analysis may contribute to identifying biological, historical, and socioeconomic determinants in long-term trends of health status and health inequalities as well as examining Korean's aging trajectories and temporal trends of period and cohort effects. For designing effective health policies that improve Korean population's health and reduce health inequalities, it is essential to understand independent effects of the three temporal factors by using the innovative APC models.

Cancer Statistics in Korea: Incidence, Mortality, Survival, and Prevalence in 2014 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study presents the 2014 nationwide cancer statistics in Korea, including cancer incidence, survival, prevalence, and mortality. MATERIALS AND METHODS: Cancer incidence data from 1999 to 2014 was obtained from the Korea National Cancer Incidence Database and followed until December 31, 2015. Mortality data from 1983 to 2014 were obtained from Statistics Korea. The prevalence was defined as the number of cancer patients alive on January 1, 2015, among all cancer patients diagnosed since 1999. Crude and age-standardized rates (ASRs) for incidence, mortality, prevalence, and 5-year relative survivals were also calculated. RESULTS: In 2014, 217,057 and 76,611 Koreans were newly diagnosed and died from cancer respectively. The ASRs for cancer incidence and mortality in 2014 were 270.7 and 85.1 per 100,000, respectively. The all-cancer incidence rate has increased significantly by 3.4% annually from 1999 to 2012, and started to decrease after 2012 (2012-2014; annual percent change, –6.6%). However, overall cancer mortality has decreased 2.7% annually since 2002. The 5-year relative survival rate for patients diagnosed with cancer between 2010 and 2014 was 70.3%, an improvement from the 41.2% for patients diagnosed between 1993 and 1995. CONCLUSION: Age-standardized cancer incidence rates have decreased since 2012 and mortality rates have also declined since 2002, while 5-year survival rates have improved remarkably from 1993-1995 to 2010-2014 in Korea.

Prediction of Cancer Incidence and Mortality in Korea, 2017 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study aimed to report on cancer incidence and mortality for the year 2017 in Korea in order to estimate the nation’s current cancer burden. MATERIALS AND METHODS: Cancer incidence data from 1999 to 2014 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2015 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observe age-specific cancer rates against observed years, and then multiplying the projected age-specific rates by the age-specific population. The Joinpoint regression model was used to determine at which year the linear trend changed significantly; we only used data of the latest trend. RESULTS: A total of 221,143 new cancer cases and 80,268 cancer deaths are expected to occur in Korea in 2017. The most common cancer sites are the colorectum, stomach, lung, thyroid, and breast. These five cancers represent half of the overall burden of cancer in Korea. For mortality, the most common sites are the lung, liver, colorectal, stomach, and pancreas. CONCLUSION: The incidence rate of all cancers in Korea appears to have decreased mainly because of a decrease in thyroid cancer. These up-to-date estimates of the cancer burden in Korea could be an important resource for planning and evaluation of cancer-control programs.

Nationwide Population-Based Incidence and Survival Rates of Malignant Central Nervous System Germ Cell Tumors in Korea, 2005-2012 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Malignant central nervous system (CNS) germ cell tumors (GCTs), although rare, are thought to occur more frequently among Asians. However, a recent population-based study revealed no differences in GCT incidence between Asians and Caucasians. Therefore, this study was conducted to determine the incidence and survival rates of CNS GCTs using the national cancer incidence database, and to compare these rates to those in the United States and Japan. MATERIALS AND METHODS: We extracted CNS GCT patients diagnosed between 2005 and 2012 from the Korea Central Cancer Registry database. Age-standardized rates (ASRs), annual percentage change, and the male-female incidence rate ratios (IRRs) were calculated. To estimate the survival rate, we used data for patients diagnosed between 2005 and 2010 and followed their cases until December 31, 2013. RESULTS: The ASR for CNS GCT between 2005 and 2012 was 0.179 per 100,000 (95% confidence interval, 0.166 to 0.193), with an overall male-to-female (M:F) IRR of 2.95:1. However, when stratified by site, the M:F IRR was 13.62:1 for tumors of the pineal region and 1.87:1 for those located in nonpineal regions. The most frequent histologic type was germinoma (76.0%), and the most frequent location was the suprasellar region (48.5%). The 5-year survival rate of germinoma patients was 95.3%. CONCLUSION: The incidence rate of CNS GCTs in Korea during 2005-2012 was 0.179 per 100,000, which was similar to that of the Asian/Pacific Islander subpopulation in the United States. Moreover, the CNS GCT survival rate in Korea was similar to rates in Japan and the United States.