An intraosseous epidermal cyst is a rare benign cystic lesion. It is thought to result from congenital factors or trauma and can lead to bone destruction because the cyst develops at the soft tissue around the bone. Radiological findings of intraosseous epidermal cysts are a well-defined radiolucent lesion, with cortical expansion. It is important to differentiate an intraosseous epidermal cyst with other disease developed at distal phalanx because its clinical and radiological findings are similar. We report two rare cases of intraosseous epidermal cysts that developed at the distal phalanx.
Epidermal Cyst*

Patient survival is one of the most important measures for the evaluation of progress in cancer patient care across the wide spectrum from diagnosis to treatment. The optimal monitoring method for cancer patient survival is to estimate survival based on representative data from cancer patients in the population, which is only achievable through using population-based cancer registration data. Relative survival is used to compare the survival experience in a study cohort that expected to result from background population mortality rates. This technique is useful when the cause of death is not accurate or not available, since it provides a measure of excess mortality in a group of patients with a certain disease. The purpose of this article is to demonstrate the procedures for estimating relative survival using the statistical software Stata. For this survival analysis to show the procedure, the example data set was randomly selected from the National Cancer Incidence Database, which was used in a recent article reporting the overall relative survival of cancer patients diagnosed during 1993-2002 in Korea.
Cause of Death ; Cohort Studies ; Dataset ; Diagnosis ; Humans ; Incidence ; Korea ; Mortality ; Patient Care ; Survival Analysis*

Purpose: This study aimed to report the projected cancer incidence and mortality for the year 2022 to estimate Korea’s current cancer burden. Materials and Methods: Cancer incidence data from 1999 to 2019 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2020 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against their respective years and then by multiplying the projected age-specific rates by the anticipated age-specific population for 2022. A joinpoint regression model was used to determine the year in which the linear trend changed significantly; we only used the data of the latest trend. Results: In total, 274,488 new cancer cases and 81,277 cancer deaths are expected to occur in Korea in 2022. The most common cancer site is expected to be the thyroid, followed by the lung, colon and rectum, breast, and stomach. These five cancers are expected to represent half of the overall burden of cancer in Korea. The most common type of cancer leading to death is expected to be lung cancer, followed by liver, colorectal, pancreatic, and gallbladder cancers. Conclusion The incidence rates for all types of cancer in Korea are estimated to gradually decrease. These up-to-date estimates of the cancer burden in Korea could be an important resource for planning and evaluating cancer-control programs.

PURPOSE: South Korea has the highest incidence rate of thyroid cancer in the world, and the incidence rate continues to increase. The aim of this study was to determine the age-period-cohort effects on the incidence of thyroid cancer in Korea. MATERIALS AND METHODS: Using the Korean National Cancer registry database, age-standardized incidence rates and annual percent changes (APCs) in thyroid cancer according to sex and histologic type were analyzed between 1997 and 2011. Age-period-cohort models were applied using an intrinsic estimator method according to sex. RESULTS: In both men and women, the incidence of thyroid cancer showed a sharp increase from 1997 through 2011. Among the histologic types, papillary carcinoma showed the greatest increase, with APCs of 25.1% (95% confidence interval [CI], 22.7% to 27.5%) in men and 23.7% (95% CI, 21.9% to 25.5%) in women, whereas anaplastic carcinoma did not show a significant increase in either sex. An increase in overall thyroid cancer incidence over time was observed in all birth cohorts. An age-period-cohort model indicated a steeply increasing period effect, which increased prominently from 1997 to 2011 in both men and women. The age effect showed an inverted U-shaped trend. The cohort effect tended to show a slight increase or remain constant from 1952 to 1977, followed by a decrease. CONCLUSION: The period effect can explain the sharp increase in thyroid cancer incidence, strongly suggesting the role of thyroid screening.
Carcinoma ; Carcinoma, Papillary ; Cohort Effect ; Cohort Studies ; Female ; Humans ; Incidence* ; Korea ; Male ; Mass Screening ; Parturition ; Thyroid Gland ; Thyroid Neoplasms*

PURPOSE: This study aimed to report on cancer incidence and mortality for the year 2018 to estimate Korea's current cancer burden. MATERIALS AND METHODS: Cancer incidence data from 1999 to 2015 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2016 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against observed years, 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 the data of the latest trend. RESULTS: A total of 204,909 new cancer cases and 82,155 cancer deaths are expected to occur in Korea in 2018. The most common cancer sites were lung, followed by stomach, colorectal, breast and liver. These five cancers represent half of the overall burden of cancer in Korea. For mortality, the most common sites were lung cancer, followed by liver, colorectal, stomach and pancreas. CONCLUSION: The incidence rate of all cancer in Korea are estimated to decrease gradually, mainly due to decrease of 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.
Breast ; Forecasting ; Incidence* ; Korea* ; Linear Models ; Liver ; Lung ; Lung Neoplasms ; Mortality* ; Pancreas ; Stomach ; Thyroid Neoplasms

PURPOSE: This study presents the 2015 nationwide cancer statistics in Korea, including the incidence, survival, prevalence, and mortality. MATERIALS AND METHODS: Cancer incidence data from 1999 to 2015 was obtained from the Korea National Cancer Incidence Database and followed until December 31, 2016. Mortality data from 1983 to 2015 were obtained from Statistics Korea. The prevalence was defined as the number of cancer patients alive on January 1, 2016, among all cancer patients diagnosed since 1999. Crude and age-standardized rates (ASRs) for incidence, mortality and prevalence and 5-year relative survivals were also calculated. RESULTS: Herein, 214,701 and 76,855 Koreans were newly diagnosed and died from cancer in 2015, respectively. The ASRs for cancer incidence and mortality in 2015 were 258.9 and 82.0 per 100,000, respectively. The overall cancer incidence rate has increased significantly by 3.4% annually from 1999 to 2012, and started to decrease after 2012 (2012-2015, annual percent change, −6.1%). However, the overall cancer mortality has decreased 2.7% annually since 2002. The 5-year relative survival rate for patients diagnosed with cancer between 2011 and 2015 was 70.7%, 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 declined since 2002; however, the 5-year survival rates have improved remarkably from 1993-1995 to 2011-2015 in Korea.
Humans ; Incidence* ; Korea* ; Mortality* ; Prevalence* ; Survival Rate

PURPOSE: This study aimed to report on cancer incidence and mortality for the year 2019 to estimate Korea's current cancer burden. MATERIALS AND METHODS: Cancer incidence data from 1999 to 2016 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2017 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against observed years, 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 used only the data of the latest trend. RESULTS: A total of 221,347 new cancer cases and 82,344 cancer deaths are expected to occur in Korea in 2019. The most common cancer sites thus far have been the lung, followed by the stomach, colon and rectum, breast, and liver. These five cancers represent half of the overall burden of cancer in Korea. For cancer associated mortality, the most common sites were lung, followed by the liver, colon and rectum, stomach, and pancreas. CONCLUSION: The incidence rate of all cancer in Korea is estimated to decrease gradually. These up-todate estimates of the cancer burden in Korea could be an important resource for planning and evaluating cancer-control programs.
Breast ; Colon ; Forecasting ; Incidence ; Korea ; Linear Models ; Liver ; Lung ; Mortality ; Pancreas ; Rectum ; Stomach

PURPOSE: This study presents the 2016 nationwide cancer statistics in Korea, including cancer incidence, survival, prevalence, and mortality. MATERIALS AND METHODS: Cancer incidence data from 1999 to 2016 were obtained from the Korea National Cancer Incidence Database and followed until December 31, 2017. Mortality data from 1983 to 2016 were obtained from Statistics Korea. The prevalence was defined as the number of cancer patients alive on January 1, 2017 among all cancer patients diagnosed since 1999. Crude and age-standardized rates (ASRs) for incidence, mortality, and prevalence and 5-year relative survivals were also calculated. RESULTS: Overall, 229,180 and 78,194 Koreans were newly diagnosed and died from cancer in 2016, respectively. The ASRs for cancer incidence and mortality in 2016 were 269.0 and 79.8 per 100,000 individuals, respectively. The all-cancer incidence rate increased significantly by 3.6% annually from 1999 to 2011 and started to decrease after 2011 (2011-2016; annual percent change, –3.1%). However, overall cancer mortality has decreased 2.7% annually since 2002. The 5-year relative survival rate for patients diagnosed with cancer between 2012 and 2016 was 70.6%, an improvement from the 41.2% for patients diagnosed between 1993 and 1995. CONCLUSION: The cancer prevalence in Korea has increased very fast as survival has improved remarkably. The high prevalence of cancer emphasizes the need for comprehensive cancer control efforts in Korea.
Humans ; Incidence ; Korea ; Mortality ; Prevalence ; Survival Rate

Purpose: This study aimed to report the projected cancer incidence and mortality for the year 2021 to estimate Korea’s current cancer burden. Materials and Methods: Cancer incidence data from 1999 to 2018 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2019 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against their respective years and then by multiplying the projected age-specific rates by the anticipated age-specific population for 2021. A joinpoint regression model was used to determine the year in which the linear trend changed significantly; we only used the data of the latest trend. Results: In total, 259,999 new cancer cases and 81,567 cancer deaths are expected to occur in Korea in 2021. The most common cancer site is expected to be the lung, followed by the thyroid, colon and rectum, breast, and stomach. These five cancers are expected to represent half of the overall burden of cancer in Korea. The most common type of cancer leading to death is expected to be lung cancer, followed by liver, colorectal, pancreatic, and stomach cancers. Conclusion The incidence rates for all types of cancer in Korea are estimated to gradually decrease. These up-to-date estimates of the cancer burden in Korea could be an important resource for planning and evaluating cancer-control programs.

Purpose: This study aimed to report the projected cancer incidence and mortality for the year 2021 to estimate Korea’s current cancer burden. Materials and Methods: Cancer incidence data from 1999 to 2018 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2019 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against their respective years and then by multiplying the projected age-specific rates by the anticipated age-specific population for 2021. A joinpoint regression model was used to determine the year in which the linear trend changed significantly; we only used the data of the latest trend. Results: In total, 259,999 new cancer cases and 81,567 cancer deaths are expected to occur in Korea in 2021. The most common cancer site is expected to be the lung, followed by the thyroid, colon and rectum, breast, and stomach. These five cancers are expected to represent half of the overall burden of cancer in Korea. The most common type of cancer leading to death is expected to be lung cancer, followed by liver, colorectal, pancreatic, and stomach cancers. Conclusion The incidence rates for all types of cancer in Korea are estimated to gradually decrease. These up-to-date estimates of the cancer burden in Korea could be an important resource for planning and evaluating cancer-control programs.