The clinical utilization of radiation therapy in Korea between 2009 and 2013

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Original Article Radiat Oncol J ;(): pissn eissn The clinical utilization of radiation therapy in Korea between and JinKyu Kang, MD, MiSook Kim, MD, PhD,, WonIl Jang, MD, Young Seok Seo, MD, Hee Jin Kim, Chul Koo Cho, MD, PhD, Hyung Jun Yoo, MD, Eun Kyung Paik, MD, Yu Jin Cha, MD, Hyun Jin Song, MPharm, PhD Department of Radiation Oncology and, Radiation Medicine Policy Development Center, Korea Institute of Radiological & Medical Sciences, Seoul; College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, Korea Purpose: The purpose of this study was to estimate the clinical utilization of radiation therapy (RT) in Korea between and. Materials and Methods: We analyzed open claims data from the Health Insurance Review and Assessment Service. The subjects were patients who had diagnostic codes CC or DD according to the th revision of the International Classification of Diseases, with procedure codes indicating RT treatment. Results: The total number of patients who received RT in,,,, and were,,,,,,,, and,, respectively. Among them, the total numbers of male and female patients were,/, in,,/, in,,/, in,,/, in, and,/, in. The five cancers that were most frequently treated with RT between and were breast, lung, colorectal, liver, and uterine cervical cancers. However, the fifth most common cancer treated with RT that replaced uterine cervical cancer in was prostate cancer. The three leading types of cancer among the male patients were lung, colorectal, and liver cancers, whereas in female patients, they were breast, uterine cervical, and lung cancers. The type of cancer most commonly treated by RT was cancer of the central nervous system in patients aged years or less, breast cancer in patients aged years, and lung cancer in patients aged years or more. Conclusion: Data from this study provided the clinical utilization of RT in Korea between and. Keywords: Neoplasms, Radiotherapy, Statistics, Korea Introduction Cancer is a major public health problem in Korea. According to the annual report of the Korea Central Cancer Registry, more than, people have been diagnosed with cancer every year since, with a steadily increasing cancer incidence []. This trend is expected to persist in the future because of population aging, westernized lifestyle, development of diagnostic tools that can detect cancer, and a medical system that encourages cancer screening []. As radiation therapy (RT) is an indispensable part of cancer treatment, it is reasonable and necessary to estimate the Received April, Revised May, Accepted June. Correspondence: MiSook Kim, MD, PhD, Department of Radiation Oncology, Korea Institute of Radiological & Medical Sciences, Nowonro, Nowongu, Seoul, Korea. Tel: +, Fax: +, Email: mskim@kirams. re.kr This is an Open Access article distributed under the terms of the Creative Commons Attribution NonCommercial License (http://creativecommons.org/ licenses/bync/./) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Copyright. The Korean Society for Radiation Oncology

Clinical utilization of RT clinical utilization of RT for understanding the status and development of cancer treatment in Korea. The most up to date official records on the clinical utilization of RT in Korea were reported for the period []. These records were compiled using questionnairebased methods over a long period and possibly had recall bias. Recently, we reported the findings of a pilot study for the clinical utilization of RT in and [] in order to estimate the feasibility of statistics using claims data from the Health Insurance Review and Assessment Service (HIRA). In previous studies [], we categorized patients according to the cancer site treated by RT, instead of their primary cancer diagnostic codes. In the present study, the patients were categorized according to their primary cancer codes rather than their metastasis status or the site of treatment. Moreover, a previous study [] analyzed patients who only had C code diseases. Patients who had ductal carcinoma in situ of the breast or benign brain tumor treated with RT could not be included in the total count of patients who received RT because they are D code diseases and are therefore classified as benign. Consequently, the actual total number of patients who received RT was underestimated. Therefore, in the present study, we analyzed the data from patients having both D code and C code diseases. The aim of the present study was to estimate the clinical utilization of RT in the period using claims data from the HIRA. Materials and Methods The detailed methods using claims data from the HIRA are described in a previous study []. The customized source population criteria for this study are shown in Table. In this study, we included not only patients with International Classification of Disease (ICD) diagnostic codes CC, but also those with diagnostic codes DD (including carcinoma in situ or benign neoplasms), who were also associated with at least one of the procedure codes related to RT treatment. In our previous study, we categorized Table. The customized source population List Treatment period Type of healthcare facility Diagnostic code Type of insurance Hospital region Sex Age Criterion // // Tertiary, secondary C C, D D Health insurance, medical aid National Male, female All ages Table. Procedure codes related to radiation therapy Procedure code HDHD HDHD HD HDHD HD HD HD HDHD, HDHD HD HZ Name of procedure code Teletherapy single or opposed ports Rotational irradiation Dimensional conformal therapy Brachytherapy Total body irradiation Total body lymph node irradiation Total skin electron beam therapy Stereotactic radiation therapy Proton therapy Intensitymodulated radiation therapy the patients who had diagnostic codes for metastasis (C ) based on whether they received RT to the metastatic site, irrespective of the patient s primary cancer diagnostic code. However, in this study, the patients were categorized according to their primary cancer codes rather than their metastasis status, even if they had diagnostic codes indicating metastasis. For example, if the patient had code C for primary lung cancer and code C. for brain metastasis, the patient was categorized as having primary lung cancer instead of brain metastasis. This method of categorization was to identify the number of patients who underwent RT for their primary cancers. However, if the patient only had a diagnostic code for metastasis, we could not determine the primary cancer diagnosis; therefore, the patient was categorized as unknown primary. If the patient had both C and D diagnostic codes, it was assumed the patient had received RT for the disease with the C diagnostic code. We analyzed the claims data from the HIRA in order to identify the total number of patients who underwent RT, and the number of patients who received RT by primary cancer diagnosis, gender, and age group between and in Korea. In addition, through the classification of the procedure codes (Table ), we estimated the total number of patients who received specific RT modalities, including brachytherapy, intensitymodulated radiation therapy (IMRT), stereotactic radiation therapy (SRT), and proton therapy. Results The total number of patients who received RT in,,,, and were,,,,,,,, and,, respectively (Fig. ). Among them, the total number of cancer patients (CC) who received RT in,,

JinKyu Kang, et al No. of patients,,,,,,,,,, D code C code,,,,,,,,,,,, No. of patients, Female, Male,,,,,,,,,,,,,,,,,,,, Year Year Fig.. The total number of patients who underwent radiation therapy between and in Korea. Fig.. The total numbers of male and female patients who received radiation therapy between and in Korea.,, and were,,,,,,,, and,, respectively. The total numbers of male and female patients who received RT were,/, in,,/, in,,/, in,,/, in, and,/, in (Fig. ). The distribution of patients who received RT by cancer diagnosis between and is shown in Table. The five most common cancers treated with RT between and were breast, lung, colorectal, liver, and uterine cervical cancers. However, the fifth most common cancer treated with RT in was prostate cancer instead of uterine cervical cancer. The three leading types of cancer among male patients were lung, colorectal, and liver cancers, and those among female patients were breast, uterine cervical, and lung cancers. Breast cancer patients constituted a quarter of the total number of cancer patients who underwent RT, and approximately half of the female cancer patients. Carcinoma in situ of the breast treated with RT was the most common among the diseases with code D. The benign neoplasms of the meninges and the central nervous system were second and third most common among Table. The distribution of cancer patients who underwent radiation therapy based on primary diagnosis between and No. of patients who received radiation therapy Category Primary diagnosis (diagnostic code) Breast Gastrointestinal Thoracic (C) Colorectum (CC) Liver (C) Esophagus (C) Stomach (C) Pancreas (C) Gallbladder & biliary (CC) Anus (C) Small bowel (C) Other (C) Lung (C) Thymus (C) Mediastinum (C) Trachea (C) Other (C),,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, Continued on the next page.

Clinical utilization of RT Table. Continued Head & neck Gynecologic Genitourinary CNS Lymphoma Category Soft tissue Myeloma & plasmacytoma Thyroid Leukemia Skin Malignant melanoma Primary bone & cartilage Endocrine Unknown primary Total no. of cancer patients Carcinoma in situ of the breast Benign neoplasm of meninges Benign neoplasm of CNS Benign neoplasm of endocrine Other D code diseases Total D code patients Total CNS, central nervous system. Primary diagnosis (diagnostic code) Larynx (C) Oropharynx (C, CC) Oral cavity (CC) Nasopharynx (C) Salivary gland (CC) Hypopharynx (CC) Paranasal sinus (C) Nasal cavity (C) Eye & orbit (C) Lip (C) Other (C) Uterine cervix (C) Uterine corpus (CC) Ovary & tubes (C) Vagina & vulva (CC) Other (CC) Prostate (C) Ureter & bladder (CC) Kidney (CC) Penis & testis (C, CC) Other (C) Brain (CC) Spinal cord (C) Other (C) NonHodgkin s lymphoma (CC) Hodgkin s disease (C) Other (C) (C, C) (C) (C) (CC) (C) (C) (CC) (CC) (C,C, CC, C) (D) (D) (D) (DD) (DD, DD, DD) No. of patients who received radiation therapy,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

JinKyu Kang, et al Table. The number of patients who underwent radiation therapy by cancer diagnosis and age group in Primary diagnosis Breast (C) Colorectum (CC) Liver (C) Esophagus (C) Stomach (C) Pancreas (C) Gallbladder & biliary (CC) Anus (C) Small bowel (C) Other (C) Lung (C) Thymus (C) Mediastinum (C) Trachea (C) Other (C) Larynx (C) Oropharynx (C, CC) Oral cavity (CC) Nasopharynx (C) Salivary gland (CC) Hypopharynx (CC) Paranasal sinus (C) Nasal cavity (C) Eye & orbit (C) Lip (C) Other (C) Uterine cervix (C) Uterine corpus (CC) Ovary & tubes (C) Vagina & vulva (CC) Other (CC) Prostate (C) Ureter & bladder (CC) Kidney (CC) Penis & testis (C, CC) Other (C) Brain (CC) Spinal cord (C) Other (C) NonHodgkin s lymphoma (CC) Hodgkin s disease (C) Other (C) No. of patients who received radiation therapy by age group s or under s s s s s or older Total,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, Continued on the next page.

Clinical utilization of RT Table. Continued Primary diagnosis Soft tissue (C, C) Myeloma & plasmacytoma (C) Thyroid (C) Leukemia (CC) Skin (C) Malignant melanoma (C) Primary bone & cartilage (CC) Endocrine (CC) Unknown primary (C, C, CC, C) Total No. of patients who received radiation therapy by age group s or under s s s s s or older Total,,,,,,,, Table. The distribution of patients who received radiation therapy according to specific radiation therapy modalities Radiation therapy modality Brachytherapy Intensitymodulated radiation therapy Stereotactic radiation therapy Proton therapy Year,,,,,,,,,,,,, the diseases with code D. The distribution of patients who received RT in based on cancer diagnosis and age group is shown in Table. The most common cancer was that of the central nervous system for patients aged years or less, while breast cancer was the most common cancer in patients aged years, and lung cancer was the most common cancer in patients aged years or more. Similar trends were observed for previous years. The distribution of patients who received RT with specific modalities is shown in Table. Because National health insurance had not covered IMRT and proton therapy before, the number of patients who received IMRT and proton therapy before was not calculated. Discussion and Conclusion This study was conducted to analyze the clinical utilization of RT between and in Korea using claims data from the HIRA. The total number of patients who underwent RT increased % % per year between and (Fig. ). Considering the annual cancer incidence [,], although the percentage of patients who underwent RT increased from % to % during these years, it remained below % (Fig. ). Table shows the utilization rate of RT, which is defined as No. of patients Total number of patients who underwent radiation therapy Cancer incidence Utilization rate of radiation therapy,,,,,,,,,,,.%,.%.%.%,,, Year.% Fig.. Cancer incidence and the total number of patients who received radiation therapy between and in Korea. the proportion of all cancers with indications for RT by country []. This value can be dependent on the distributions of cancer types and stages. According to these reports, about % % of cancer patients in developed or developing countries would be candidates for RT treatment. Although the optimal utilization rate of RT in Korea was not reported yet, Utilization rate of radiation therapy (%)

JinKyu Kang, et al Table. List of relevant studies conducted on the utilization rates of radiation therapy by country Author Year Country Delaney et al. [] Jaen Olasolo et al. [] Barton et al. [] Borras et al. [] Rosenblatt et al. [] Australia Spain Australia European countries Ghana, Philippines, Tunisia, Serbia, Costa Rica, Romania, Malaysia, Uruguay, Slovenia Optimal utilization rate of radiation therapy (%)....... it is estimated to be within the same range. Even though the optimal RT utilization rate has been criticized for potentially overestimating the demand for RT [], the clinical utilization rate of RT in Korea could be estimated to be much lower than the optimal utilization rate of RT. Generally, the number of cancer patients who underwent RT for primary cancer increased steadily; however, the number of uterine cervical cancer patients remained approximately at, during these years. While, the number of prostate cancer patients who received RT notably increased during this period, and consequently, prostate cancer became the fifth most common cancer in replacing the cervical cancer. This might not only be attributed to the increased prevalence of prostate cancer, but also to the improvement of RT techniques including IMRT or SRT. In terms of RT modalities, while the numbers of patients who received brachytherapy were similar for each year between and, the cases receiving IMRT notably increased from to, and this increase is expected to continue in the future because of national health insurance coverage of IMRT. Similar to IMRT, the number of cases treated with SRT also has steadily increased during these years. Because the claims data from the HIRA only included that of the insured cases and the number of uninsured treatments could not be recorded, the actual number of patients who received proton therapy is expected to be more than the reported number. In comparison to the results from a previous study [], differences were observed in the total number of patients who underwent RT in and. One of the reasons for the difference could be attributed to the different collection time of claims data from the HIRA, considering that some patients data are registered after or more years. Therefore, the total number of patients who received RT in the same year might not indicate the actual number. This study could provide useful clinical utilization data for RT in Korea, and we aim to continuously provide the results on the clinical utilization of RT using claims data from the HIRA in the form of an annual report in the future. Conflict of Interest No potential conflict of interest relevant to this article was reported. Acknowledgments This work was supported by the National Nuclear R&D program of the Ministry of Education, Science and Technology, Republic of Korea. References. Jung KW, Won YJ, Kong HJ, Oh CM, Seo HG, Lee JS. Cancer statistics in Korea: incidence, mortality, survival and prevalence in. Cancer Res Treat ;:.. Jung KW, Won YJ, Kong HJ, Oh CM, Lee DH, Lee JS. Cancer statistics in Korea: incidence, mortality, survival, and prevalence in. Cancer Res Treat ;:.. Jung KW, Won YJ, Kong HJ, et al. Cancer statistics in Korea: incidence, mortality, survival, and prevalence in. Cancer Res Treat ;:.. Oh CM, Won YJ, Jung KW, et al. Cancer statistics in Korea: incidence, mortality, survival, and prevalence in. Cancer Res Treat ;:.. Lee TJ, Kim S, Cho HJ, Lee JH. The incidence of thyroid cancer is affected by the characteristics of a healthcare system. J Korean Med Sci ;:.. Suh M, Choi KS, Park B, et al. Trends in cancer screening rates among Korean men and women: results of the Korean National Cancer Screening Survey,. Cancer Res Treat ;:.. Yoo SY, Kim MS, Ji YH, Cho CK, Yang KM, You HJ. Statistics for Department of Radiation Oncology (). J Korean Soc Ther Radiol Oncol ;:.

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