Prevalence of survivors of childhood cancer based on a population-based cancer registry in Osaka, Japan.

Although the survival rate of patients with childhood cancer has greatly improved, long-term survivors face specific problems such as the late effects of cancer treatment. In this study, we estimated the number of people who had experienced childhood cancer to predict their needs for medical care and social resources. Using data from the population-based Osaka Cancer Registry, we identified children aged 0-14 years who were diagnosed with cancer between 1975 and 2019. We estimated the prevalence on December 31, 2019, and the 5- and 10-year prevalence (i.e., the number of survivors living up to 5 or 10 years after the diagnosis of cancer) over time. The prevalence proportion was age-standardized using a direct standardization method. The prevalence estimates for Osaka were applied to the national population to determine the national prevalence in Japan. Among 8186 patients diagnosed with childhood cancer in Osaka, 5252 (987 per million) survived until December 31, 2019. The 5-year prevalence per million increased from 194 in 1979 to 417 in 2019 (+116%), while the 10-year prevalence increased from 391 in 1984 to 715 in 2019 (+83%). Based on the long-term registry data, an estimated 73,182 childhood cancer survivors were living in Japan by the end of 2019. The increasing 5-year and 10-year prevalence proportions indicate the continued need for cancer survivorship support for children, adolescents, and young adults. These estimates of the prevalence of childhood cancer survivors, including long-term survivors, may be useful for policymakers and clinicians to plan and evaluate survivorship care.

Trends in patterns of treatment and survival of colorectal cancer patients using cancer registry data in Japan: 1995-2015.

Recent advances in treating colorectal cancer (CRC) have increased the importance of multidisciplinary treatment. This study aimed to clarify trends in the treatment and survival of CRC using population-based cancer registry data in Japan. We analyzed the survival of CRC cases diagnosed from 1995 through 2015 from a population-based cancer registry of six prefectures. The year of diagnosis was classified into five periods, and the trends in the detailed categorization of treatments and survival were identified. We calculated net survival and excess hazard of death from cancer using data on 256,590 CRC patients. The use of laparoscopic surgery has been increasing since 2005 and accounts for the largest proportion of treatment types in the most recent period. Net survival of CRC patients diagnosed after 2005 remained high for laparoscopic surgery and endoscopic surgery (endoscopic mucosal resection or endoscopic submucosal dissection). There was an upward trend in treatment with chemotherapy in addition to open and laparoscopic surgery. Using the excess hazard ratio at the regional stage since 2005, there has been a significant improvement in survival in the younger age group and the rectum cancer group. By type of treatment, there was a tendency toward significant improvement in the open surgery + chemotherapy group. We clarified the trends in treating CRC and the associated trends in survival. Continuous survey based on population-based data helps monitor the impact of developments in treatment.

Subsite-specific trends in mid- and long-term survival for head and neck cancer patients in Japan: A population-based study.

Advances in diagnostic techniques and treatment modalities have impacted head and neck cancer (HNC) prognosis, but their effects on subsite-specific prognosis remain unclear. This study aimed to assess subsite-specific trends in mid- and long-term survival for HNC patients diagnosed from 1993 to 2011 using data from population-based cancer registries in Japan. We estimated the net survival (NS) for HNC by subsite using data from 13 prefectural population-based cancer registries in Japan. Changes in survival over time were assessed by multivariate excess hazard model of mortality. In total, 68,312 HNC patients were included in this analysis. We observed an overall improvement in 5-year NS for HNC patients in Japan. However, survival varied among subsites of HNC, with some, such as naso-, oro- and hypopharyngeal cancers, showing significant improvement in both 5- and 10-year NS, whereas others such as laryngeal cancer showed only a slight improvement in 5-year NS and no significant change in 10-year NS after adjustment for age, sex and stage. In conclusion, the study provides insights into changing HNC survival by site at the population level in Japan. Although advances in diagnostic techniques and treatment modalities have improved survival, these improvements are not shared equally among subsites.

Endoscopic Removal of Premalignant Lesions Reduces Long-Term Colorectal Cancer Risk: Results From the Japan Polyp Study.

BACKGROUND & AIMS: To date, no regional evidence of long-term colorectal cancer (CRC) risk reduction after endoscopic premalignant lesion removal has been established. We aimed to analyze this over a long-term follow-up evaluation. METHODS: This was a prospective cohort study of participants from the Japan Polyp Study conducted at 11 Japanese institutions. Participants underwent scheduled follow-up colonoscopies after a 2-round baseline colonoscopy process. The primary outcome was CRC incidence after randomization. The observed/expected ratio of CRC was calculated using data from the population-based Osaka Cancer Registry. Secondary outcomes were the incidence and characteristics of advanced neoplasia (AN). RESULTS: A total of 1895 participants were analyzed. The mean number of follow-up colonoscopies and the median follow-up period were 2.8 years (range, 1-15 y) and 6.1 years (range, 0.8-11.9 y; 11,559.5 person-years), respectively. Overall, 4 patients (all males) developed CRCs during the study period. The observed/expected ratios for CRC in all participants, males, and females, were as follows: 0.14 (86% reduction), 0.18, and 0, respectively, and 77 ANs were detected in 71 patients (6.1 per 1000 person-years). Of the 77 ANs detected, 31 lesions (40.3%) were laterally spreading tumors, nongranular type. Nonpolypoid colorectal neoplasms (NP-CRNs), including flat (<10 mm), depressed, and laterally spreading, accounted for 59.7% of all detected ANs. Furthermore, 2 of the 4 CRCs corresponded to T1 NP-CRNs. CONCLUSIONS: Endoscopic removal of premalignant lesions, including NP-CRNs, effectively reduced CRC risk. More than half of metachronous ANs removed by surveillance colonoscopy were NP-CRNs. The Japan Polyp Study: University Hospital Medical Information Network Clinical Trial Registry: University Hospital Medical Information Network Clinical Trial Registry, C000000058; cohort study: UMIN000040731.

Suicide risk among patients with cancer by sex in Japan: A population-based study.

BACKGROUND: In Japan, few studies have examined suicide risk for five-year relative survival rates for cancer sites. Since five-year relative survival rates differ by sex, we aim to examine suicide risk for patients with cancer separately for men and women. METHODS: We estimated the risk of suicide among patients with cancer by sex in Japan compared to the general population, using standardized mortality ratios (SMRs). Patients with cancer diagnosed between January 1, 1985-December 31, 2013 and registered in the Osaka Cancer Registry were followed-up with for up to 10 years. The outcome was suicide death. In addition, cancer sites were classified into three prognosis groups based on five-year relative survival rates: good (> 70%), moderate (40-70%), poor (< 40%). RESULTS: Among 623 995 patients with cancer observed for 2 349 432 person-years, 1210 patients died by suicide (867 men and 343 women). The SMRs were almost equal for men (1.66, 95% CI, 1.55-1.77) and women (1.65, 95% CI, 1.48-1.83). SMRs for cancer prognosis groups were 1.01 (95% CI, 0.84-1.22) for men and 1.47 (95% CI, 1.24-1.73) for women in the good group, 1.53 (95% CI, 1.39-1.68) for men and 1.74 (95% CI, 1.47-2.05) for women in the moderate group, and 2.54 (95% CI, 2.27-2.85) for men and 1.87 (95% CI, 1.43-2.46) for women in the poor group. CONCLUSIONS: In this population, both sexes had higher suicide risk with poor prognosis, but the difference in SMRs between the good and poor groups was smaller for women than men.

Trends in incidence and hormonal management of endometrial cancer during potentially reproductive age in Japan: a population-based study.

BACKGROUND: We aimed to investigate the trends in the incidence and treatment of endometrial cancer (EC) during potentially reproductive age in Japan, with a special focus on the relative oncologic safety of hormonal therapy (HT) over surgery. METHODS: This population-based retrospective cohort study was conducted using data from the Osaka Cancer Registry from 2004 to 2018. Women with EC were first identified and then distributions of age, stage, histology, and initial treatment were examined. Then, the relative oncologic safety of HT over surgery in patients under the age of 50 years was evaluated. RESULTS: Among the 9417 patients with EC, 1937 were diagnosed during their potentially reproductive age (< 50 years). The incidence of EC during potentially reproductive age has increased from 18.5% in 2004-2011 to 21.9% in 2012-2018. ECs during potentially reproductive age more frequently displayed favorable characteristics, such as endometrioid histology, and lower histological grade than those in non-potentially reproductive age. Among the 1223 patients diagnosed with localized endometrioid EC, 74 cases (6.0%) received HT as an initial treatment, while 1100 cases (90.0%) underwent surgery as their initial treatment. When the two treatment groups were compared, there was no significant difference in overall survival (p = 0.3713). The estimated 5-year survival rates were 100 and 98.8% in the HT and surgery groups, respectively. CONCLUSION: EC is increasingly diagnosed during potentially reproductive age in Japan. The use of HT as an initial treatment is increasing, and achieved comparable survival outcomes to urgery against localized endometrioid EC during the potentially reproductive age.

Faster surgery initiation in oral cancer patients during the COVID-19 pandemic in Osaka, Japan.

BACKGROUND: We investigated the impact of the COVID-19 pandemic on oral cancer (OC), comparing diagnosis and number of pre-operative days in the diagnosis of OC in 2019 (pre-COVID-19) and that in 2020 (during the COVID-19 pandemic). METHODS: Using data from a cancer registry-based study on the impact of COVID-19 on cancer care in Osaka (CanReCO), we collected details of sex, age, residential area, cancer site, date of diagnosis, clinical stage at first treatment and number of pre-operative days in OC patients. RESULTS: A total of 1470 OC cases were registered. Incidence of OC before and during COVID-19 was 814 and 656 cases, respectively. During the first wave of the pandemic (March to May 2020), incidence was about half that in the same period in 2019 (2019; n = 271, 2020; n = 145). Number of pre-operative days (median number of days between the first hospital visit and surgery date) was significantly shorter during the COVID-19 year (24.5 days) than in the pre-COVID-19 year (28 days, p = 0.0015). CONCLUSIONS: Incidence of OC during the COVID-19 pandemic was lower than in pre-COVID-19. Despite disruption in the healthcare system, the number of pre-operative days for OC cases was shorter during the pandemic.

Impact of a board certification system and adherence to the clinical practice guidelines for gastric cancer on risk-adjusted surgical mortality after distal and total gastrectomy in Japan: a questionnaire survey of departments registered in the National Clinical Database.

PURPOSE: The relationship between board certification, clinical guideline implementation, and quality of gastric cancer surgery remains unclear. METHODS: A web-based questionnaire survey was administered to departments registered in the National Clinical Database (NCD) of Japan between October 2014 and January 2015. Quality indicators (QIs) based on the Donabedian model were evaluated. Structural QIs (e.g., affiliations with academic societies and board certifications) and process QIs (adherence to clinical practice guidelines for gastric cancer) were assessed using risk-adjusted odds ratios (AORs) for surgical mortality. Multivariable logistic regression models with a generalized estimating equation were used. RESULTS: A total of 835 departments performing 40,992 distal gastrectomies and 806 departments performing 19,618 total gastrectomies responded. Some certified institutions and physicians showed significant associations, with lower AORs for surgical mortality. Important process QIs included pre- and postoperative abdominal CT scanning, endoscopic resection based on progression, curative resection with D2 dissection for advanced gastric cancer, laparoscopic surgery, and HER2 testing for patients with unresectable recurrent gastric cancer. CONCLUSIONS: Multiple structural and process QIs are associated with surgical mortality after gastrectomy in Japan. Measuring and visualizing QIs may enhance healthcare improvements.

Prognostic impact of the presence or absence of prior cancer in patients with cancer using cure models: A population-based study.

Developing a subsequent cancer is one of the major concerns for cancer survivors; however, whether prior cancer could affect their prognosis is unknown. We therefore aimed to analyze how prognosis varies depending on prior cancer in patients with newly developed cancer, focusing on cancer that had been "cured." We used the record-linked database of the Osaka Cancer Registry and Vital Statistics to select 186,798 patients with stomach, colorectal, or lung cancer aged ≥40 years from 1995 to 2009 in Osaka, Japan. These cancers were defined as index cancers. We classified the patients into two groups according to whether they had a prior cancer diagnosis within 10 years before the index cancer diagnosis. The cured proportion was defined as the proportion of cancer patients with the same mortality as the general population and was estimated using the parametric mixture cure model. The cured proportion of patients with prior cancer by sex and age group was not significantly lower than those without prior cancer, except for patients with stomach cancer aged ≥65 years. According to the index cancer stage in the localized stomach or colorectal cancer, the cured proportion in patients with prior cancer was lower than in those without prior cancer. However, at any stage of lung cancer, the proportion of patients with prior cancer who had been cured was similar to patients without prior cancer, therefore prior cancer had a prognostic impact only in some patient groups based on the characteristics of their index cancer.

Cancer incidence and type of treatment hospital among children, adolescents, and young adults in Japan, 2016-2018.

Cancer in children, adolescents, and young adults (AYAs) although rare, is the leading disease-specific cause of death in Japan. This study aims to investigate cancer incidence and type of treatment hospital among children and AYAs in Japan. Cancer incidence data (2016-2018) for those aged 0-39 years were obtained from the Japanese population-based National Cancer Registry. Cancer types were classified according to the 2017 update of the International Classification of Childhood Cancer (Third Edition), and AYA Site Recode 2020 Revision. Cases were also categorized into three groups: those treated at core hospitals for pediatric cancer treatment (pediatric cancer hospitals [PCHs]), those treated at designated cancer care hospitals, and those treated at nondesignated hospitals. The age-standardized incidence rate was 166.6 (per million-person years) for children (age 0-14 years) and 579.0 for AYAs (age 15-39 years) (including all cancers and benign or uncertain-behavior central nervous system [CNS] tumors). The type of cancer varied with age: hematological malignancies, blastomas, and CNS tumors were common in children under 10 years, malignant bone tumors and soft tissue sarcomas were relatively common in teenagers, and in young adults over 20 years, carcinomas in thyroid, testis, gastrointestinal, female cervix, and breast were common. The proportion of cases treated at PCHs ranged from 20% to 30% for children, 10% or less for AYAs, and differed according to age group and cancer type. Based on this information, the optimal system of cancer care should be discussed.

Incidence of second primary cancers among survivors of childhood cancer: A population-based study, Osaka, Japan, 1975-2015.

Second primary cancer (SPC) is one of the most life-threatening late effects of childhood cancers. We investigated the incidence and survival outcomes of SPC in childhood cancer patients in Japan. Data were obtained from the population-based Osaka Cancer Registry. Individuals diagnosed with cancer at age 0-14 years during 1975-2014 and survived 2 months or longer were followed through December 2015. The risk of developing SPC was assessed with standardized incidence ratio (SIR), excess absolute risk (EAR, per 100,000 person-years), and cumulative incidence. Multivariable Poisson regression analysis was carried out to assess relative risks of SPC by treatment method. Survival analysis was undertaken using the Kaplan-Meier method. Of 7229 childhood cancer survivors, 101 (1.4%) developed SPC after a median of 11.6 years. Overall SIR was 5.0, which corresponded with 84.3 EAR. The cumulative incidence was 0.9%, 2.1%, and 3.4% at 10, 20, and 30 years, respectively. Among all SPCs, the type that contributed most to the overall burden was cancers in the central nervous system (EAR = 28.0) followed by digestive system (EAR = 15.1), thyroid (EAR = 8.3), and bones and joints (EAR = 7.8); median latency ranged from 2.0 years (lymphomas) to 26.6 years (skin cancers). Patients treated with radiotherapy alone were at a 2.58-fold increased risk of developing SPC compared to those who received neither chemotherapy nor radiotherapy. Among patients who developed SPCs, 5-year and 10-year survival probabilities after SPC diagnosis were 61.7% and 52.0%, respectively. Risk-based long-term follow-up planning is essential to inform survivorship care and help reduce the burden of SPCs in childhood cancer survivors.

Patterns of staging, treatment, and mortality in gastric, colorectal, and lung cancer among older adults with and without preexisting dementia: a Japanese multicentre cohort study.

BACKGROUND: Little is known about dementia's impact on patterns of diagnosis, treatment, and outcomes in cancer patients. This study aimed to elucidate the differences in cancer staging, treatment, and mortality in older cancer patients with and without preexisting dementia. METHODS: Using cancer registry data and administrative data from 30 hospitals in Japan, this multicentre retrospective cohort study examined patients aged 65-99 years who were newly diagnosed with gastric, colorectal, or lung cancer in 2014-2015. Dementia status (none, mild, and moderate-to-severe) at the time of cancer diagnosis was extracted from clinical summaries in administrative data, and set as the exposure of interest. We constructed multivariable logistic regression models to analyse cancer staging and treatment, and multivariable Cox regression models to analyse three-year survival. RESULTS: Among gastric (n = 6016), colorectal (n = 7257), and lung (n = 4502) cancer patients, 5.1%, 5.8%, and 6.4% had dementia, respectively. Patients with dementia were more likely to receive unstaged and advanced-stage cancer diagnoses; less likely to undergo tumour resection for stage I, II, and III gastric cancer and for stage I and II lung cancer; less likely to receive pharmacotherapy for stage III and IV lung cancer; more likely to undergo tumour resection for all-stage colorectal cancer; and more likely to die within three years of cancer diagnosis. The effects of moderate-to-severe dementia were greater than those of mild dementia, with the exception of tumour resection for colorectal cancer. CONCLUSION: Older cancer patients with preexisting dementia are less likely to receive standard cancer treatment and more likely to experience poorer outcomes. Clinicians should be aware of these risks, and would benefit from standardised guidelines to aid their decision-making in diagnosing and treating these patients.

An age-group analysis on the efficacy of chemotherapy in older adult patients with metastatic biliary tract cancer: a Japanese cancer registry cohort study.

BACKGROUND: The effectiveness of chemotherapy in older adult patients with biliary tract cancer (BTC) remains to be established, despite the fact that the majority of patients diagnosed with BTC tend to be aged ≥ 70 years. In this study, we used three databases to examine the effectiveness of chemotherapy in a large patient population aged ≥ 70 years with metastatic BTC. METHODS: Using a large Japanese database that combined three data sources (Osaka Cancer Registry, Japan's Diagnosis Procedure Combination, the hospital-based cancer registry database), we extracted the data from patients pathologically diagnosed with metastatic BTC, between January 1, 2013, and December 31, 2015, in 30 designated cancer care hospitals (DCCHs). A cohort of patients with comparable backgrounds was identified using propensity score matching. The log-rank test was used to examine how chemotherapy affected overall survival (OS). RESULTS: Among 2,622 registered patients with BTC in 30 DCCHs, 207 older adult patients aged > 70 years with metastatic BTC were selected. Chemotherapy significantly improved the prognosis of older adult patients, according to propensity score matching (chemotherapy, 6.4 months vs. best supportive care, 1.8 months, P value < 0.001). The number of patients receiving chemotherapy tends to decrease with age. Gemcitabine plus cisplatin (GC) and gemcitabine plus S-1 (oral fluoropyrimidine) (GS) combination therapy were frequently performed in the chemotherapy group for patients under 80 years of age (70-74 years, 61.7%; 75-79 years, 62.8%). In contrast, monotherapy including GEM and S-1 was more frequently performed in age groups over 80 years (80-84 years, 56.2%; 85-89 years, 77.7%; ≥90 years, 100%). In the chemotherapy group among older adult patients aged < 85 years, the median OS was significantly longer according to age-group analysis of the 5-year age range following propensity score matching. CONCLUSIONS: In older adult patients with metastatic BTC who received chemotherapy, prolonged survival was observed. Chemotherapy may be a viable option for patients with metastatic BTC who are aged < 85 years.

Evaluation of survival outcomes between minimally invasive and open surgery in the treatment of early-stage endometrial cancer: a population-based study in Osaka Japan.

OBJECTIVE: To compare the oncological outcomes between Japanese women who underwent minimally invasive surgery and those who underwent open surgery for early-stage endometrial cancer. METHODS: This population-based retrospective cohort study was conducted using data from the Osaka Cancer Registry from 2011 to 2018. Surgically treated patients for localized (uterine-confined) endometrial cancer were identified. Patients were classified into two groups according to the type of surgery (minimally invasive surgery group and open-surgery group), pathological risk factors (low-risk and high-risk), and year of diagnosis (Group 1, 2011-14; Group 2, 2015-18). Overall survival was compared between the minimally invasive surgery and open-surgery groups. RESULTS: In the analyses including all patients, there was no difference in overall survival between the minimally invasive surgery and open-surgery groups (P = 0.0797). The 4-year overall survival rate was 97.1 and 95.7% in the minimally invasive surgery and open-surgery groups, respectively. When investigated according to pathological risks, there were no differences in overall survival between the minimally invasive surgery and open-surgery groups in both the low- and high-risk groups. In the low-risk group, the 4-year overall survival rates in the minimally invasive surgery and open-surgery groups were 97.7 and 96.5%, respectively. In the high-risk group, the 4-year overall survival rates in the minimally invasive surgery and open-surgery groups were 91.2 and 93.2%, respectively. Similarly, there were no differences in overall survival between the minimally invasive surgery and open-surgery groups in both Group 1 (P = 0.4479 in low-risk and P = 0.1826 in high-risk groups) and Group 2 (P = 0.1750 in low-risk and P = 0.0799 in high-risk groups). CONCLUSION: Our study provides epidemiological evidence that minimally invasive surgery is an effective alternative to open surgery in Japanese patients with early-stage endometrial cancer.

Short-term association of air pollution with lung cancer mortality in Osaka, Japan.

Long-term air pollution exposure has been linked to increased lung cancer mortality. However, little is known about whether day-to-day fluctuations in air pollution levels are in relation to lung cancer mortality, particularly in low-exposure settings. This study aimed to evaluate the short-term associations between air pollution and lung cancer mortality. Daily data on lung cancer mortality, fine particulate matter (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), and weather conditions were collected from Osaka Prefecture, Japan, from 2010 to 2014. Generalized linear models were combined with quasi-Poisson regression were applied to evaluate the associations between each air pollutant and lung cancer mortality after adjusting for potential confounders. Mean (standard deviation) concentrations of PM2.5, NO2, SO2, and CO were 16.7 (8.6) µg/m3, 36.8 (14.2) µg/m3, 11.1 (4.0) µg/m3, and 0.51 (0.16) mg/m3, respectively. Interquartile range increases in concentrations of PM2.5, NO2, SO2, and CO (2-d moving average) were associated with 2.65% (95% confidence intervals [CIs]: 0.96%-4.37%), 4.28% (95% CIs: 2.24%-6.36%), 3.35% (95% CIs: 1.03%-5.73%), and 4.60% (95% CIs: 2.19%-7.05%) increased risk of lung cancer mortality, respectively. Stratified analyses showed that the associations were strongest in the older population and men. Exposure‒response curves showed a continuously increasing mortality risk from lung cancer with elevation of air pollution levels, without discernible thresholds. In summary, we found evidence of increased lung cancer mortality in relation to short-term elevations in ambient air pollution. These findings may merit further research to better understand this issue.

Improved long-term survival of corpus cancer in Japan: A 40-year population-based analysis.

The incidence of uterine corpus cancer has been increasing globally due to increase in obesity. However, a detailed analysis of long-term epidemiological trends of corpus cancer in Japan, where obesity is relatively minimal, has not been conducted. In this retrospective, population-based study using the Osaka Cancer Registry, we analyzed 15 255 cases of corpus neoplasia registered between 1977 and 2016. We determined the age-standardized incidence, mortality, relative survival and conditional survival rates, and the treatment trends for corpus cancer over the last 40 years in Japan. The age-standardized incidence rate of corpus neoplasia increased sharply in 2000-2011 (APC = 9.9, 95% CI: 8.4-11.3), whereas the mortality rate trended to a much more modest increase (APC = 3.3, 95% CI: 2.7-3.8). Compared to 1977-2000, 10-year survival rates for post-2000 cases of localized and regional corpus cancers significantly improved (from 87.7% [95% CI: 85.8-89.4] to 94.2% [95% CI: 92.7-95.7] and from 47.5% [95% CI: 43.3-51.6] to 64.4% [95% CI: 61.0-67.6], respectively). This was largely associated with the significant increase in the percentage of localized and regional patients who received chemotherapy instead of radiation as an adjuvant therapy combined to surgery (P < .001 for both). We found that each histological type (endometrioid carcinoma, serous carcinoma, clear cell carcinoma and carcinosarcoma) has different characteristics of trend of age-standardized incidence rate, relative survival and distribution of extent of disease. In endometrioid carcinoma, the age-standardized incidence rate increased consistently after 1990, but the rate of increase was decreasing after 1997.

Surgical volume threshold to improve 3-year survival in designated cancer care hospitals in 2004-2012 in Japan.

In Japan, cancer care hospitals designated by the national government have a surgical volume requirement of 400 annually, which is not necessarily defined based on patient outcomes. This study aimed to estimate surgical volume thresholds that ensure optimal 3-year survival for three periods. In total, 186 965 patients who had undergone surgery for solid cancers in 66 designated cancer care hospitals in Osaka between 2004 and 2012 were examined using data from a population-based cancer registry. These hospitals were categorized by the annual surgical volume of each 50 surgeries (eg, 0-49, 50-99, and so on). Using multivariable Cox proportional hazard regression, we estimated the adjusted 3-year survival probability per surgical volume category for 2004-2006, 2007-2009, and 2010-2012. Using the joinpoint regression model that computes inflection points in a linear relationship, we estimated the points at which the trend of the association between surgical volume and survival probability changes, defining them as surgical volume thresholds. The adjusted 3-year survival ranges were 71.7%-90.0%, 68.2%-90.0%, and 79.2%-90.3% in 2004-2006, 2007-2009, and 2010-2012, respectively. The surgical volume thresholds were identified at 100-149 in 2004-2006 and 2007-2009 and 200-249 in 2010-2012. The extents of change in the adjusted 3-year survival probability per increase of 50 surgical volumes were +4.00%, +6.88%, and +1.79% points until the threshold and +0.41%, +0.30%, and +0.11% points after the threshold in 2004-2006, 2007-2009, and 2010-2012, respectively. The existing surgical volume requirements met our estimated thresholds. Surgical volume thresholds based on the association with patient survival may be used as a reference to validate the surgical volume requirement.

A retrospective 5-year survival analysis of surgically resected gastric cancer cases from the Japanese Gastric Cancer Association nationwide registry (2001-2013).

BACKGROUND: The nationwide registry of the Japanese Gastric Cancer Association collected data of surgically resected cases of gastric cancer between 2001 and 2013. These retrospective analyses aimed to delineate tumor characteristics, surgical history, and survival distribution. METHODS: Data from 254,706 patients with primary gastric cancer were included. The 5-year survival rates were calculated for various subsets of prognostic factors. RESULTS: The number of patients over 70 years old increased from 2001 to 2013. The frequency with which laparoscopic gastrectomy was opted for increased dramatically (from 3.5 to 40.8%) in 13 years. We focused on the patients registered between 2010 and 2013, for whom data collection was based on the 3rd edition of the Japanese classification and guidelines. Five-year overall survival (OS) rate among 92,305 patients with resected tumors was 70.6%. The 5-year OS rates of patients with pathological stage IA, IB, IIA, IIB, IIIA, IIIB, IIIC, and IV disease were 89.6%, 83.2%, 77.6%, 68.1%, 59.3%, 45.6%, 29.9%, and 14.0%, respectively. CONCLUSION: Our detailed analysis highlights the historical changes in outcomes of surgically treated gastric malignancies in Japan, and provides robust dataset for future analysis.

Impact of endoscopic surveillance on mortality of metachronous esophageal and head and neck cancer after esophageal endoscopic resection.

BACKGROUND AND AIM: As more superficial esophageal cancer (EC) patients are being treated with endoscopic resection (ER), it is important to understand the outcomes, including survival data, of patients who develop metachronous EC and head and neck cancer (HNC). We aimed to evaluate the long-term surveillance and survival outcomes of metachronous EC and HNC after esophageal ER. METHODS: This study included 627 patients who underwent ER of superficial esophageal squamous cell carcinoma from 2008 to 2016 and were generally followed by annual or biannual esophagogastroduodenoscopy up to 2019 at Osaka International Cancer Institute. Data on metachronous cancer development and causes of death were collected from an integrated database of hospital-based cancer registry and Vital Statistics of Japan. RESULTS: During a median (range) follow-up period of 67.4 (3.8-142.7) months, 230 patients (36.7%) developed 500 metachronous ECs and 126 patients (20.1%) developed 239 metachronous HNCs, post-ER of index EC. The 3-year, 5-year, and 7-year cumulative incidences were 25.8%, 36.0%, and 43.6% for metachronous EC and 10.9%, 16.0%, and 26.9% for metachronous HNC, respectively. No patients died of metachronous EC, and only seven patients (1.1%) died of metachronous HNC. The 3-year, 5-year, and 7-year disease-specific survival rates were 99.8%, 99.6%, and 98.6%, respectively. CONCLUSIONS: The incidences of metachronous EC and HNC increase with time over 5 years after esophageal ER; therefore, surveillance endoscopy should be continued over 5 years. Endoscopic surveillance is useful for survivors after esophageal ER given the high incidence and extremely low mortality of metachronous EC and HNC.

Cancer in adolescents and young adults in Japan: epidemiology and cancer strategy.

According to national cancer registry data in Japan, approximately 20,000 adolescents and young adults (AYAs, age 15-39 years) are newly diagnosed with cancer each year. Improvements in treatment and care for AYAs with cancer are included in the Phase Three Basic Plan to Promote Cancer Control Programs in Japan. This article reviews current cancer incidence and survival for AYAs with cancer in Japan using population-based cancer registry data. Mortality data through 2019 from the Vital Statistics of Japan are also described. Encouragingly, the 5-year survival probability for AYA cancers has continued to improve, in parallel with childhood cancers, and the mortality rate has decreased. There has been increasing attention to these vulnerable patients and improved partnerships and collaboration between adult and pediatric oncology; however, obstacles to the care of this population still exist at multiple levels. These obstacles relate to specific areas: research efforts and enrollment in clinical trials on AYA malignancies, AYA-specific psychosocial support such as education, financial support, and oncofertility care, and cancer care systems. It is important for Japanese oncologists, health care providers, and health policy makers to recognize that the AYA population remains vulnerable and still have unmet needs.