Prognosis of Patients with Esophageal Carcinoma After Routine Thoracic Duct Resection: A Propensity-matched Analysis of 12,237 Patients Based on the Comprehensive Registry of Esophageal Cancer in Japan.

OBJECTIVE: To clarify whether routine thoracic duct (TD) resection improves the prognosis of patients with esophageal cancer after radical esophagectomy. SUMMARY OF BACKGROUND DATA: Although TD resection can cause nutritional disadvantage and immune suppression, it has been performed for the resection of surrounding lymph nodes. METHODS: We analyzed 12,237 patients from the Comprehensive Registry of Esophageal Cancer in Japan who underwent esophagectomy between 2007 and 2012. TD resection and preservation groups were compared in terms of prognosis, perioperative outcomes, and initial recurrent patterns using strict propensity score matching. Particularly, the year of esophagectomy and history of primary cancer of other organs were added as covariates. RESULTS: After propensity score matching, 1638 c-Stage I-IV patients participated in each group. The 5 year overall survival and cause-specific survival rates were 57.5% and 65.6% in the TD-resected group and 55.2% and 63.4% in the TD-preserved group, respectively, without significant differences. The TD-resected group had significantly more retrieved mediastinal nodes (30 vs 21, P < 0.0001) and significantly fewer lymph node recurrence (376 vs 450, P = 0.0029) compared with the TD-preserved group. However, the total number of distant metastatic organs was significantly greater in TD-resected group than in the TD-preserved group (499 vs 421, P = 0.0024). CONCLUSIONS: TD resection did not improve survival in patients with esoph-ageal cancer. Despite having retrieved more lymph nodes, TD resection caused distant metastases in more organs compared to TD preservation. Hence, prophylactic TD resection should not be recommended in patients with esophageal cancer.

Is Thoracic Duct Resection Necessary for Esophageal Squamous Cell Carcinoma Patients Treated with Neoadjuvant Chemoradiotherapy? A Propensity-Matched Analysis Based on the Comprehensive Registry of Esophageal Cancer in Japan.

BACKGROUND: The thoracic duct (TD) plays an important role in nutrition and immunity but is often resected with the esophagus when dissecting surrounding lymph nodes in patients with esophageal squamous cell carcinoma (ESCC). We examined whether indiscriminate TD resection improved the prognosis of patients with ESCC treated with neoadjuvant chemoradiotherapy (NACRT) followed by esophagectomy. METHODS: A total of 440 patients treated with NACRT followed by esophagectomy between 2007 and 2012 were analyzed using data from the Comprehensive Registry of Esophageal Cancer in Japan. The propensity score-matched TD resection and TD preservation groups were compared in terms of short- and long-term outcomes. RESULTS: After matching, there were 85 patients in both groups. No significant differences were found between groups in either overall survival or cause-specific survival rates at 5 years: 44.2% and 49.0% in the TD resection group, and 39.8% and 47.2% in the TD preservation group, respectively. Furthermore, the number of retrieved mediastinal lymph nodes was significantly greater in the TD resection group than in the TD preservation group (26 vs. 15, p < 0.0001). In contrast, TD resection was associated with metastasis to a significantly greater number of distant organs than TD preservation (49 vs. 32, p = 0.049). CONCLUSIONS: TD resection did not contribute to improved survival in patients with ESCC but did lead to metastases in more organs than TD preservation. Consequently, indiscriminate TD resection might be avoided in patients with ESCC treated with NACRT followed by esophagectomy.

Comprehensive registry of esophageal cancer in Japan, 2015.

BACKGROUND: The registration committee for esophageal cancer in the Japan Esophageal Society (JES) has collected the patients' characteristics, treatment, and outcomes of patients who underwent any treatment during 2015 in Japan. METHODS: We analyzed patients' data who had visited the participating hospitals in 2015. We collected the data using the National Clinical Database with a web-based data collection system. We used the Japanese Classification of Esophageal Cancer 10th edition by JES and the TNM classification by the Union of International Cancer Control (UICC) for cancer staging. RESULTS: A total of 9368 cases were registered from 355 institutions in Japan. Squamous cell carcinoma and adenocarcinoma accounted for 86.7% and 7.4%, respectively. The 5-year survival rates of patients treated by endoscopic resection, concurrent chemoradiotherapy, radiotherapy alone, and esophagectomy were 87.2%, 33.5%, 24.2%, and 59.9%, respectively. Esophagectomy was performed in 5172 cases. Minimally invasive approaches were selected for 60.6%, and 54.4% underwent thoracoscopic esophagectomy. The operative mortality (within 30 days after surgery) was 0.79% and the hospital mortality was 2.3%. The survival curves showed an excellent discriminatory ability both in the clinical and pathologic stages by the JES system. The survival of pStage IV was better than IIIC in the UICC system because pStage IV included the patients with supraclavicular lymph node metastasis (M1 LYM). CONCLUSION: We hope this report improves all aspects of diagnosing and treating esophageal cancer in Japan.

Comprehensive registry of esophageal cancer in Japan, 2014.

BACKGROUND: The registration committee for esophageal cancer in the Japan Esophageal Society (JES) has collected the patients' characteristics, treatment, and outcomes annually. METHODS: We analyzed the data of patients who had visited the participating hospitals in 2014. We collected the data with a web-based data collection system using the National Clinical Database. We used the Japanese Classification of Esophageal Cancer 10th edition by JES and the TNM classification 7th edition by the Union of International Cancer Control (UICC) for cancer staging. RESULTS: A total of 9026 cases were registered from 344 institutions in Japan. Squamous cell carcinoma and adenocarcinoma accounted for 87.9% and 7.1%, respectively. The 5-year survival rates of patients treated using endoscopic resection, concurrent chemoradiotherapy, radiotherapy alone, and esophagectomy were 87.1%, 33.7%, 25.3%, and 59.3%, respectively. Esophagectomy was performed in 5204 cases. Concerning the approach used for esophagectomy, 48.1% of the cases were treated thoracoscopically. The operative mortality (within 30 days after surgery) was 0.75%, and the hospital mortality was 2.0%. The survival curves showed an excellent discriminatory ability both in the clinical and pathologic stages by the JES system. The survival of pStage IV was better than IIIC in the UICC system, because pStage IV included the patients with supraclavicular lymph-node metastasis (M1 LYM). CONCLUSION: We hope that this report contributes to improving all aspects of diagnosing and treating esophageal cancer in Japan.

Comprehensive registry of esophageal cancer in Japan, 2013.

BACKGROUND: Esophageal cancer is the eighth most common cause of cancer mortality in Japan. More than 11,000 people had died from esophageal cancer in 2018. The Japan Esophageal Society has collected the data on patients' characteristics, performed treatment, and outcomes annually. METHODS: We analyzed the data of patients who had first visited the participating hospitals in 2013. In 2019, the data collection method was changed from an electronic submission to a web-based data collection using the National Clinical Database (NCD). Japanese Classification of Esophageal Cancer 10th by the Japan Esophageal Society (JES) and UICC TNM Classification 7th were used for cancer staging RESULTS: A total of 8019 cases were registered from 334 institutions in Japan. Squamous cell carcinoma and adenocarcinoma accounted for 87.8% and 6.3%, respectively. The 5-year survival rates of patients treated using endoscopic resection, concurrent chemoradiotherapy, radiotherapy alone, or esophagectomy were 88.3%, 32.4%, 24.4%, and 59.3%, respectively. Esophagectomy was performed in 4910 cases. The operative and the hospital mortality rates were 0.77% and 1.98%, respectively. The survival curves showed a good discriminatory ability both in the clinical and pathologic stages by the JES system. The 5-year survival rate of patients with pStage IV in the UICC classification that included patients with supraclavicular node metastasis was better than that of patients with pStage IVb in JES classification. CONCLUSION: We hope this report contributes to improving all aspects of the diagnosis and treatment of esophageal cancer in Japan.

Chemoradiotherapy and radiotherapy alone in patients with esophageal cancer aged 80 years or older based on the Comprehensive Registry of Esophageal Cancer in Japan.

BACKGROUND: There has been no definitive evidence of chemoradiotherapy being superior to radiotherapy alone in patients aged 80 years or older. The purpose of the present study was to evaluate the results of radiotherapy and chemoradiotherapy in patients aged 80 years or older with esophageal cancer in the Japanese Nationwide Cancer Database. METHODS: A total of 358 patients aged 80 years or older who were treated with radiotherapy alone or with chemoradiotherapy for esophageal cancer between 2009 and 2011 were enrolled. RESULTS: The 5-year overall survival (OS) rates in patients with cStages 0-I, II, III and IV were 40.9%, 24.7%, 12.2% and 4.9%, respectively. The 5-year cause-specific survival (CSS) rates in patients aged 80 years or older with cStages 0-I, cStage II, cStage III and cStage IV were 73.5%, 41.4%, 25.3% and 7.4%, respectively. In patients treated with radiotherapy alone, the 5-year OS rates for patients with cStages 0-I, II, III and IV were 36.5%, 12.0%, 5.4% and 0%, respectively. In patients treated with chemoradiotherapy, the 5-year OS rates for patients with cStages 0-I, II, III and IV were 45.0%, 36.1%, 16.4% and 7.1%, respectively. In multivariate analysis, chemoradiotherapy, early stage and squamous cell carcinoma were significantly favorable prognostic factors for OS in patients aged 80 years or older (p < 0.001, p < 0.001 and p = 0.0323, respectively). We were unable to evaluate toxicities, because of lack of information in the registry. CONCLUSION: Concurrent chemotherapy with radiotherapy for esophageal cancer in patients aged 80 years or older is a significantly favorable prognostic factor for OS. However, chemoradiotherapy should be carefully selected in elderly patients.

Comparison of the effects of radiotherapy doses of 50.4 Gy and 60 Gy on outcomes of chemoradiotherapy for thoracic esophageal cancer: subgroup analysis based on the Comprehensive Registry of Esophageal Cancer in Japan from 2009 to 2011 by the Japan Esophageal Society.

BACKGROUND: In definitive chemoradiotherapy (CRTx) for esophageal cancer, a radiotherapy (RT) dose of 50.4 Gy in 28 fractions has been the standard in many countries, while 60 Gy in 30 fractions has been frequently used in Japan. To clarify the optimal RT dose in CRTx for esophageal cancer, we compared clinical outcomes with the two doses using data from the Comprehensive Registry of Esophageal Cancer in Japan by the Japan Esophageal Society (JES). METHODS: Of the patients enrolled in the registry for 2015-2017 surveys (patients treated between 2009 and 2011), 996 patients who received definitive CRTx with 50.4 Gy or 60 Gy for thoracic esophageal cancer were eligible for analysis. RESULTS: The complete response (CR) rates in the 50.4 Gy and 60 Gy groups were 49.1% and 46.4%, respectively (p = 0.5851). The 5-year overall survival (OS) rates in the 50.4 Gy group and 60 Gy group for stages I, II/III and IV were 64.2% and 57.2%, 35.0% and 27.0%, and 18.0% and 15.3%, respectively. Since no significant difference was found between the two groups, the 50.4 Gy group was not inferior to the 60 Gy group with regard to OS. CONCLUSIONS: The analysis revealed that the 50.4 Gy group had a non-inferior outcome in comparison with the 60 Gy group for stages I, II/III and IV thoracic esophageal cancer. These results were obtained from a large database for the first time in Japan.

Current status of radiotherapy for patients with thoracic esophageal cancer in Japan, based on the Comprehensive Registry of Esophageal Cancer in Japan from 2009 to 2011 by the Japan Esophageal Society.

BACKGROUND: Although esophagectomy is the standard treatment for resectable esophageal cancer, chemoradiotherapy or radiotherapy alone is also selected for some cases. However, there have been very few detailed studies conducted on a large scale on the efficacy of these treatments in Japan. METHODS: Of the patients enrolled in the Comprehensive Registry of Esophageal Cancer in Japan by the Japan Esophageal Society for the 2015-2017 surveys (patients treated between 2009 and 2011), the data of 388 patients treated by definitive radiotherapy alone (RTx) and 1964 patients treated by definitive chemoradiotherapy (CRTx) were analyzed. RESULTS: The median age of the patients was 78 years in the RTx group and 69 years in the CRTx group; thus, the proportion of elderly patients was significantly higher in the RTx group than in the CRTx group (p < 0.0001). With regard to the rates of treatment by the two modalities according to the depth of invasion, extent of lymph node metastasis, and disease stage, the treatment rate by CRTx increased more significantly than that by RTx as the disease progressed (p < 0.0001). With regard to the distribution of the total irradiation dose, 11.4% and 2.3% of patients in the RTx and CRTx groups, respectively, received a dose of 67 Gy or more; thus, the RTx group received significantly higher total irradiation doses (p < 0.0001). In the RTx group, the 5-year overall survival rate was 23.2%, and the rates in patients with cStage 0-I, II, III, and IV disease were 41.8%,18.5%, 9.3%, and 13.9%, respectively. In the patients of the RTx group showing complete response (CR), the 5-year overall survival rate was 46.6% and the rates in patients with cStage 0-I, II, III, and IV disease were 54.8%, 39.6%, 32.4%, and 38.9%, respectively. In the CRTx group, the 5-year overall survival rate was 30.6% and the rates in patients with cStage 0-I, II, III, and IV disease were 57.8%, 47.8%, 23.4%, and 13.0%, respectively. In the patients of the CRTx group showing CR, the 5-year overall survival rate was 59.2% and the rates in patients with cStage 0-I, II, III, and IV disease were 67.9%, 59.5%, 56.5%, and 39.6%, respectively. CONCLUSION: This study revealed the current status of treatment of esophageal cancer in Japan, and we think that we have been able to establish the grounds for explaining to patients with esophageal cancer and their families the treatment decisions made for them in daily clinical practice.

Correction to: Comprehensive Registry of Esophageal Cancer in Japan, 2011.

In the original publication of the article, the below name of institutions were not included in the table of Institution-registered cases in 2011.

Thin-section CT findings in peripheral lung cancer of 3 cm or smaller: are there any characteristic features for predicting tumor histology or do they depend only on tumor size?

BACKGROUND: Ground-glass opacity (GGO) is reported to be characteristic to lepidic growth of neoplasm in subsolid nodules. In solid nodules of lung cancer, however, there is no characteristic feature to be reported. PURPOSE: To study if there are any thin-section CT findings characteristic to tumor histology or if they are only related to tumor size in solid nodules of the lung cancer. MATERIAL AND METHODS: This study included 106 solid peripheral lung cancers of 3 cm or smaller (56 adenocarcinomas, 33 squamous cell carcinomas, and 17 small cell carcinomas) in which 16-slice CT with 1 mm collimation was performed before surgery. Six morphologic findings (presence or absence of lobulation, coarse spiculation, air bronchogram, cavity, pleural tag, and pleural-based lesion) and four measurements (ratio of the greatest transverse and vertical diameter to the shortest transverse diameter and density of lobulation and coarse spiculation) on thin-section CT images were evaluated. Density of lobulation (coarse spiculation) was defined as the ratio of lobulation (coarse spiculation) number to the greatest transverse diameter of a nodule. RESULTS: Air bronchogram (P < 0.01) was the only significant factor for predicting lung adenocarcinoma. The prevalence of air bronchogram was significantly greater in adenocarcinoma than in squamous cell carcinoma (P < 0.01) or small cell carcinoma (P < 0.01). As the tumor size advanced, significantly positive linear trends were seen in the prevalence of lobulation (P < 0.01), coarse spiculation (P < 0.01), and pleural tag (P < 0.01), and the mean values of density of lobulation (P < 0.01) and coarse spiculation (P < 0.01), while the significant negative linear trend was seen in the ratio of vertical diameter to the shortest transverse (P = 0.02). CONCLUSION: Air bronchogram on thin-section CT is characteristic feature of solid adenocarcinoma of the lung. However, other thin-section CT findings are irrelevant to tumor histology and related only to tumor size.

Japanese structure survey of radiation oncology in 2009 with special reference to designated cancer care hospitals.

BACKGROUND: The structure of radiation oncology in designated cancer care hospitals in Japan was surveyed in terms of equipment, personnel, patient load, and geographic distribution, and compared with the structure in other radiotherapy facilities and the previous survey. METHODS: The Japanese Society for Therapeutic Radiology and Oncology surveyed the national structure of radiation oncology in 2009. The structures of 365 designated cancer care hospitals and 335 other radiotherapy facilities were compared. RESULTS: Designated cancer care hospitals accounted for 50.0% of all the radiotherapy facilities in Japan. The patterns of equipment and personnel in designated cancer care hospitals and the other radiotherapy facilities were, respectively, as follows: linear accelerators per facility: 1.4 and 1.0; dual-energy function: 78.6 and 61.3%; three-dimensional conformal radiotherapy function: 88.5 and 70.0%; intensity-modulated radiotherapy function: 51.6 and 25.3%; annual number of patients per linear accelerator: 301.3 and 185.2; Ir-192 remote-controlled after-loading systems: 31.8 and 4.2%; and average number of full-time equivalent radiation oncologists per facility: 1.8 and 0.8. Compared with the previous survey, the ownership ratio of equipment and personnel improved in both designated cancer care hospitals and the other radiotherapy facilities. Annual patient loads per full-time equivalent radiation oncologist in the designated cancer care hospitals and the other radiotherapy facilities were 225.5 and 247.6, respectively. These values exceeded the standard guidelines level of 200. CONCLUSIONS: The structure of radiation oncology in designated Japanese cancer care hospitals was more mature than that in the other radiotherapy facilities. There is still a shortage of personnel. The serious understaffing problem in radiation oncology should be corrected in the future.

Source strength assay of iodine-125 seeds sealed within sterile packaging.

Early-stage prostate cancer is widely treated by iodine-125 (I-125) seed implantation. While quality assurance methods are in place to assure consistency in I-125 seed source strength, current methods involve the breaking of the sterilization package, raising issues concerning sterility and time limitations. The purpose of this study was to develop a method of characterizing the total source strength of I-125 seeds within a cartridge that has been sealed within a sterilization package and to evaluate the probability of detecting an out-of-calibration seed (aberrant seed). We defined a protocol to determine the ability of a well-type ionization chamber to detect aberrant I-125 seeds within a cartridge sealed in the sterilization package. A novel jig for a well-type ionization chamber was designed to accommodate the sterilization package. One seed was chosen randomly from two cartridges containing five or 15 seeds (0.544 U source strength) and was exchanged with aberrant seeds of six different source strengths. The source strength was measured at each position within the cartridge. The results indicated that the response of the well chamber was sensitive to changes in the aberrant seed position within the cartridge and the source strength of the aberrant seed. The correlation coefficient between single seed and batch assay results was high (0.998). A novel jig and a measurement method using a well ionization chamber were developed, which allowed for a batch assay characterization of the total source strength of I-125 seeds within a cartridge sealed within sterilization package. This method is simple, time-saving, and offers greater practical application.

A JROD survey: nationwide overview of radiotherapy data from 2015 to 2021.

The purpose of this survey was to examine the status of radiotherapy in Japan based on the cases registered in the Japanese Radiation Oncology Database (JROD), from 2015 to 2021, and to provide basic data to help improve the usefulness of the JROD in the future. The study population consisted of patients who underwent radiotherapy between 2014 and 2020 and did not opt out of the study. The survey item data analyzed in this study were entered into the database at each radiotherapy institution by referring to medical records from the preceding year. Our results show that the number of registered radiotherapy institutions and cases increased by ~50% in 2019 compared to those in 2015 (to 113 institutions and 60 575 cases, respectively). Among the survey item categories, the registration rate was lowest for prognostic information (13.9% on average over the 7-year period). In terms of the Japanese Society for Radiation Oncology disease site, the breast; lung, trachea and mediastinum and urogenital sites accounted for >50% of the total cases. The average survival and mortality rates over the 7-year study period were 67.4 and 17.4%, respectively. The X-ray radiotherapy completion rate exceeded 90% for all years and across all disease categories. 192Ir-based brachytherapy and 223Ra-based radionuclide therapy accounted for an average of 61.9 and 44.6%, respectively, of all corresponding cases over the 7-year period. In conclusion, this survey enables us to infer the actual status of radiotherapy in Japan based on the analysis of relevant nationwide data.

Japanese structure survey of radiation oncology in 2015.

This article describes the ongoing structure of radiation oncology in Japan in terms of equipment, personnel, patient load and geographic distribution to identify and overcome any existing limitations. From May 2016 to August 2018, the Japanese Society for Radiation Oncology conducted a questionnaire based on the Japanese national structure survey of radiation oncology in 2015. Data were analyzed based on the institutional stratification by the annual number of new patients treated with radiotherapy per institution. The estimated annual numbers of new and total (new plus repeat) patients treated with radiation were 225 000 and 271 000, respectively. Additionally, the estimated cancer incidence was 891 445 cases with approximately 25.2% of all newly diagnosed patients being treated with radiation. The types and numbers of treatment devices actually used included linear accelerator (linac; n = 936), Gamma Knife (n = 43), 60Co remote afterloading system (RALS; n = 21), and 192Ir RALS (n = 129). The linac system used dual-energy functions in 754 units, 3D conformal radiotherapy functions in 867, and intensity-modulated radiotherapy (IMRT) functions in 628. There were 899 Japan Radiological Society/Japanese Society for Radiation Oncology-certified radiation oncologists (RO), 1213.9 full-time equivalent (FTE) ROs, 2394.2 FTE radiotherapy technologists (RTT), 295.7 FTE medical physicists, 210.2 FTE radiotherapy quality managers, and 906.1 FTE nurses. The frequency of IMRT use significantly increased during this time. In conclusion, the Japanese structure of radiation oncology has clearly improved in terms of equipment and utility although there was a shortage of personnel in 2015.

Japanese structure survey of radiation oncology in 2007 with special reference to designated cancer care hospitals.

BACKGROUND AND PURPOSE: The structure of radiation oncology in designated cancer care hospitals in Japan was investigated in terms of equipment, personnel, patient load, and geographic distribution. The effect of changes in the health care policy in Japan on radiotherapy structure was also examined. MATERIAL AND METHODS: The Japanese Society of Therapeutic Radiology and Oncology surveyed the national structure of radiation oncology in 2007. The structures of 349 designated cancer care hospitals and 372 other radiotherapy facilities were compared. RESULTS: Respective findings for equipment and personnel at designated cancer care hospitals and other facilities included the following: linear accelerators/facility: 1.3 and 1.0; annual patients/linear accelerator: 296.5 and 175.0; and annual patient load/full-time equivalent radiation oncologist was 237.0 and 273.3, respectively. Geographically, the number of designated cancer care hospitals was associated with population size. CONCLUSION: The structure of radiation oncology in Japan in terms of equipment, especially for designated cancer care hospitals, was as mature as that in European countries and the United States, even though the medical costs in relation to GDP in Japan are lower. There is still a shortage of manpower. The survey data proved to be important to fully understand the radiation oncology medical care system in Japan.

Changing trend in the patterns of pretreatment diagnostic assessment for patients with cervical cancer in Japan.

OBJECTIVE: Cancer staging systems should be responsive to the development of diagnostic tools. The International Federation of Gynecology and Obstetrics (FIGO) cervical cancer guidelines were modified in 2009 regarding the pretreatment assessment. We report the recent Japanese patterns of pretreatment workup for cervical cancer. METHODS: The Japanese Patterns of Care Study (PCS) working group analyzed the pretreatment diagnostic assessment data of 609 patients with cervical cancer treated with definitive radiotherapy in the two survey periods (1999-2001, 324; 2003-2005, 285) in Japan. Sixty-one of 640 institutions were selected for this survey using a stratified two-staged cluster sampling method. RESULTS: The use of optional examinations in the latest FIGO guidelines such as intravenous urography, cystoscopy, and proctoscopy was gradually decreasing. Surgical staging was rarely performed in either survey period. Computed tomography (CT) and magnetic resonance imaging (MRI) were widely used, and MRI has become increasingly prevalent even between the two survey periods. Primary lesion size and pelvic lymph node status was evaluated by CT/MRI for most patients in both surveys. CONCLUSIONS: The use of CT/MRI that is encouraged in the latest FIGO staging guidelines already replaced intravenous urography, cystoscopy, and proctoscopy in Japan. Japanese patients received the potential benefit of CT/MRI because prognostic factors such as primary lesion size and pelvic lymph node status were evaluated by these modalities. The use of cystoscopy and proctoscopy should be continuously monitored in the future PCS survey because only CT/MRI could lead to the stage migration for patients on suspicion of bladder/rectum involvement on CT/MRI.