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This study aimed to assess the clinical outcomes of neoadjuvant modified short-course radiotherapy (mSC-RT) for rectal metastatic adenocarcinoma.Data from 14 patients who underwent mSC-RT followed by surgery for primary tumors were retrospectively analyzed. Twelve patients received systemic chemotherapy for 18 weeks. A 2.5 Gy dose twice daily, up to a total dose of 25 Gy in 10 fractions, over 5 consecutive days was administered through mSC-RT. Surgery for primary tumor was performed five weeks (range=3-7 weeks) after mSC-RT. Nine patients underwent adjuvant chemotherapy. The median follow-up was 38.5 months.No patients developed grade ≥3 toxicities before surgery. Three patients developed local failures and 10 died during the follow-up period. The 1-, and 3-year local control rates were 91.7% and 71.3%, respectively. The median overall survival (OS) was 45.1 months. The 1-, and 3-year OS rates were 85.7% and 56.3%, respectively. Patients with stage IVA showed significantly better OS than those with stage IVB disease.mSC-RT followed by delayed surgery was well-tolerated and led to good local control in patients with rectal metastatic adenocarcinoma. mSC-RT could be a treatment option for patients with rectal metastatic adenocarcinoma as it is less likely to lead to cessation of systemic chemotherapy.

Background/aim To evaluate the incidence and grade of radiation pneumonitis after volumetric modulated arc therapy (VMAT) performed for the treatment of non-small cell cancer (NSCLC). Patients and methods Fifty consecutive non-surgical candidates with NSCLC underwent VMAT. Thirty-five patients had stage-III tumors and 15 had recurrent tumors. The prescribed radiation dose for the gross tumor and the elective nodal area was 69 Gy in 30 fractions and 51 Gy in 30 fractions, respectively. Results Radiation pneumonitis developed in 38 patients (76%, 38/50), and grade ≥2 radiation pneumonitis developed in 11 patients (22%, 11/50). The percentage of lung volume that received a dose in excess of 5 Gy (V5), V10, V20, V30, and the mean lung dose (MLD) in the bilateral and ipsilateral lung were significantly associated with the development of grade ≥2 radiation pneumonitis. Conclusion The incidence and degree of radiation pneumonitis are acceptable following treatment of NSCLC with VMAT.

Simple Summary Both short- and long-course neoadjuvant radiotherapy (NA-RT) followed by surgery have been adopted as standard treatments for locally advanced rectal cancer (LARC). We hypothesized that a modified short-course radiotherapy (mSC-RT) using an accelerated hyperfractionated regimen, with a dose of 2.5 Gy twice daily up to a total dose of 25 Gy in 10 fractions, can provide a favorable therapeutic ratio in comparison with the conventional regimens. Ninety-seven consecutive LARC patients undergoing mSC-RT followed by delayed surgery were analyzed in this retrospective study. Additionally, potential prognostic factors for overall survival (OS) were also assessed. The results showed that mSC-RT followed by delayed surgery achieved equivalent anti-tumor efficacy and acute toxicity that were comparable with long- and short-course NA-RT, respectively. A neutrophil-to-lymphocyte ratio (NLR) ≥ 1.83 was independently associated with poor OS in LARC patients receiving mSC-RT. Thus, mSC-RT can be a promising alternative to both standard long- and short-course NA-RT regimens. Abstract This study aimed to assess the clinical outcomes and predictive factors of neoadjuvant modified short-course radiotherapy (mSC-RT) for locally advanced rectal cancer (LARC). Data from 97 patients undergoing mSC-RT followed by radical surgery for LARC were retrospectively analyzed. A 2.5 Gy dose twice daily up to a total dose of 25 Gy in 10 fractions was administered through mSC-RT, and this was delivered with oral chemotherapy in 95 (97.9%) patients. Radical surgery was performed 6 (range, 3–13) weeks after mSC-RT. The median follow-up among surviving patients was 43 (8–86) months. All patients completed neoadjuvant radiotherapy with no acute toxicity grade ≥ 3. Three- and five-year local control rates were 96.3% and 96.3%, respectively. Three- and five-year overall survival (OS) rates were 92.7% and 79.8%, respectively. Univariate analyses revealed that poor OS was associated with no concurrent administration of capecitabine, C-reactive-protein-to-albumin ratio ≥ 0.053, carcinoembryonic antigen ≥ 3.4 ng/mL, and neutrophil-to-lymphocyte ratio (NLR) ≥ 1.83 (P = 0.045, 0.001, 0.041, and 0.001, respectively). Multivariate analyses indicated that NLR ≥ 1.83 was independently associated with poor OS (p = 0.018). mSC-RT followed by delayed surgery for LARC was deemed feasible and resulted in good clinical outcomes, whereas poor OS was associated with high NLR.

We evaluated the evolving structure of radiation oncology in Japan in terms of equipment, personnel, patient load and geographic distribution to identify and overcome any existing limitations. From March 2012 to August 2015, the Japanese Society for Radiation Oncology conducted a questionnaire based on the Japanese national structure survey of radiation oncology in 2011. 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 211 000 and 250 000, respectively. Additionally, the estimated cancer incidence was 851 537 cases with approximately 24.8% of all newly diagnosed patients being treated with radiation. The types and numbers of treatment devices actually used included linear accelerator (LINAC; n = 836), telecobalt (n = 3), Gamma Knife (n = 46), 60Co remote afterloading system (RALS; n = 24), and 192Ir RALS (n = 125). The LINAC system used dual-energy functions in 619 units, 3D conformal radiotherapy functions in 719 and intensity-modulated radiotherapy (IMRT) functions in 412. There were 756 JRS or JASTRO-certified radiation oncologists, 1018.5 full-time equivalent (FTE) radiation oncologists, 2026.7 FTE radiotherapy technologists, 149.1 FTE medical physicists, 141.5 FTE radiotherapy quality managers and 716.3 FTE nurses. The frequency of IMRT use significantly increased during this time. To conclude, although there was a shortage of personnel in 2011, the Japanese structure of radiation oncology has clearly improved in terms of equipment and utility.

Aim We sought to improve error detection ability during volume modulated arc therapy (VMAT) by dividing and evaluating the treatment plan. Background VMAT involves moving a beam source delivering radiation to tumor tissue through an arc, which significantly decreases treatment time. Treatment planning for VMAT involves many parameters. Quality assurance before treatment is a major focus of research. Materials and methods We used an established VMAT prostate treatment plan and divided it into 12° × 30° sections. In all the sections, only image data that generated errors in one segment and those that were integrally acquired were evaluated by a gamma analysis. This was done with five different patient plans. Results The integrated image data resulting from errors in each section was 100% (tolerance 0.5 mm/0.5%) in the gamma analysis result in all image data. Division of the treatment plans produced a shift in the mean value of each gamma analysis in the cranial, left, and ventral directions of 94.59%, 98.83%, 96.58%, and the discrimination ability improved. Conclusion The error discrimination ability was improved by dividing and verifying the portal imaging.

We compared less invasive surgery with conventional surgery for malignant pleural mesothelioma (MPM). We retrospectively reviewed consecutive patients with MPM who received surgery at Hyogo College of Medicine between July 2004 and April 2016. Patients underwent multimodal treatment comprising chemotherapy (neoadjuvant and/or adjuvant) and surgery with or without 54 Gy hemithoracic radiotherapy. Patients were grouped into 3 groups according to the surgery intended: Conventional extrapleural pneumonectomy was intended in Group 1 (until August 2009); less invasive extrapleural pneumonectomy was intended in Group 2 (after September 2009); pleurectomy/decortication was intended in Group 3 (after September 2012). We included 152 patients (median age 64 [37-71] years; 131 men, 21 women), mostly with epithelioid subtypes (91.4%). Of them, 149 (98.0%) underwent neoadjuvant chemotherapy and 117 (77.0%) underwent surgery (60 had extrapleural pneumonectomy and 57 had pleurectomy/decortication). Macroscopic complete resection was achieved in 94.9% (111/117), and the mortality rates at 30 and 90 days were 1.7% (2/117) and 3.4% (4/117), respectively. The overall median survival time and progression-free survival for all 152 patients were 34.9 and 17.4 months. The overall median survival time for Groups 1, 2, and 3 were 18.5, 41.9, and 43.4 months, respectively. The progression-free survival for Groups 1, 2, and 3 were 12.0, 24.5, and 21.8 months, respectively. Compared with conventional surgical techniques, less invasive surgery for MPM yielded lower surgical risks and comparable or improved survival.

We evaluated the evolving structure of radiation oncology in Japan in terms of equipment, personnel, patient load, and geographic distribution to identify and overcome any existing limitations. From March 2011 to June 2013, the Japanese Society for Radiation Oncology conducted a questionnaire based on the Japanese national structure survey of radiation oncology in 2010. 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 211 000 and 251 000, respectively. Additionally, the estimated cancer incidence was 805 236 cases, with ~26.2% of all newly diagnosed patients being treated with radiation. The types and numbers of treatment devices actually used included linear accelerator (LINAC; n = 829), telecobalt (n = 9), Gamma Knife (n = 46), 60Co remote afterloading system (RALS; n = 28), and 192Ir RALS (n = 131). The LINAC system used dual-energy functions in 586 units, three-dimensional conformal radiotherapy functions in 663, and intensity-modulated radiotherapy (IMRT) functions in 337. There were 564 JASTRO-certified radiation oncologists, 959.2 full-time equivalent (FTE) radiation oncologists, 1841.3 FTE radiotherapy technologists, 131.3 FTE medical physicists, 121.5 FTE radiotherapy quality managers, and 649.6 FTE nurses. The frequency of IMRT use significantly increased during this year. To conclude, although there was a shortage of personnel in 2010, the Japanese structure of radiation oncology has clearly improved in terms of equipment and utility.

Accumulating evidence has shown that thermal ablation can induce spontaneous distant tumor regression, which is also known as abscopal effect. Abscopal effect might depend upon the activation of antitumor immune response. However, such responses induced by thermal ablation had been thought to be usually weak and that they rarely induce distant tumor regression. Recently, results of several preclinical and clinical studies have suggested that thermal ablation can induce therapeutically effective systemic antitumor immune response if appropriate immunomodulators are combined. To elucidate the mechanisms of these promising strategies, effects of thermal ablation on the immune system are overviewed. Furthermore, recent promising preclinical and clinical studies examining enhancement of systemic antitumor immune response by combining thermal ablation and immunomodulation are summarized.

Aim This study aimed to assess the utility and stability of intraoral stent during intensity-modulated radiation therapy (IMRT). Background The benefits of intraoral stents in radiotherapy are unclear. Materials and methods We analyzed 386 setup errors in 12 patients who received IMRT for head and neck cancers without intraoral stents (intraoral stent [−]) and 183 setup errors in 6 patients who received IMRT with intraoral stents (intraoral stent [+]). All patients were matched according to the immobilization method (masks and boards). Setup errors were measured as the distance from the initial setup based on the marking on the skin and mask to the corrected position based on bone matching on cone beam computed tomography. Results The mean interfractional setup errors in the right–left, craniocaudal, anterior–posterior (AP), and three-dimensional (3D) directions were −0.33, 0.08, −0.25, and 2.75 mm in the intraoral stent (−) group and −0.37, 0.24, −0.63, and 2.42 mm in the intraoral stent (+) group, respectively ( P = 0.50, 0.65, 0.01, and 0.02, respectively). The systematic errors for the same directions were 0.89, 1.46, 1.15, and 0.88 mm in the intraoral stent (−) group and 0.62, 1.69, 0.68, and 0.56 mm in the intraoral stents (+) group, respectively. The random errors were 1.43, 1.43, 1.44, and 1.22 mm in the intraoral stent (−) group and 1.06, 1.11, 1.05, and 0.92 mm in the intraoral stents (+) group, respectively. Conclusion Setup errors can be significantly reduced in the AP and 3D-directions by using intraoral stents.

Pravastatin is an inhibitor of 3-hydroxy-3-methyl- glutaryl-coenzyme A reductase that has been reported to have therapeutic applications in a range of inflammatory conditions. The aim of the present study was to assess the radioprotective effects of pravastatin in an experimental animal model. Mice were divided into two groups: The control group received ionizing radiation with no prior medication, while the pravastatin group received pravastatin prior to ionizing radiation. Pravastatin was administered orally at 30 mg/kg body weight in drinking water at 24 and 4 h before irradiation. Intestinal crypt epithelial cell survival and the incidence of apoptosis in the intestine and lung were measured post-irradiation. The effect of pravastatin on intestinal DNA damage was determined by immunohistochemistry. Finally, the effect of pravastatin on tumor response to radiotherapy was examined in a mouse mesothelioma xenograft model. Pravastatin increased the number of viable intestinal crypts and this effect was statistically significant in the ileum (P

Deformable image registration (DIR) has been an important component in adaptive radiotherapy (ART). Our goal was to examine the accuracy of ART using the dice similarity coefficient (DSC) and to determine the optimal timing of replanning. A total of 22 patients who underwent volume modulated arc therapy (VMAT) for head and neck (H&N) cancers were prospectively analyzed. The planning target volume (PTV) was to receive a total of 70 Gy in 33 fractions. A second planning CT scan (rescan) was performed at the 15th fraction. The DSC was calculated for each structure on both CT scans. The continuous variables to predict the need for replanning were assessed. The optimal cut-off value was determined using receiver operating characteristic (ROC) curve analysis. In the correlation between body weight loss and DSC of each structure, weight loss correlated negatively with DSC of the whole face (rs = -0.45) and the face surface (rs = -0.51). Patients who required replanning tended to have experienced rapid weight loss. The threshold DSC was 0.98 and 0.60 in the whole face and the face surface, respectively. Patients who showed low DSC in the whole face and the face surface required replanning at a significantly high rate (P < 0.05 and P < 0.01). Weight loss correlated with DSC in both the whole face and the face surface (P < 0.05 and P < 0.05). The DSC values in the face predicted the need for replanning. In addition, weight loss tended to correlate with DSC. DIR during ART was found to be a useful tool for replanning.

The aim of this study was to investigate the influence of chemoradiotherapy (CRT) on nutritional status and the association between changes in nutritional status and clinical outcomes (treatment completion, adverse events, perioperative complications, and relapse-free survival [RFS]) in patients with locally advanced rectal cancer (LARC).In this multicenter, phase II study, 41 patients with LARC underwent CRT for 5 wk, followed by a 6- to 8-wk interval before surgery. Body weight, body mass index (BMI), lean body mass, serum albumin, and prealbumin levels were measured before (pre-), during, and after CRT, and before surgery. Changes in these data and scores on the Malnutrition Universal Screening Tool (MUST) were calculated based on pre-CRT status.Twelve patients (29.3%) experienced body weight loss (BWL) ≥5% (defined as malnutrition) after CRT (P0.001) and before surgery (P = 0.035). Significant changes were seen in serum albumin levels and BMI during and after CRT (P0.001), and in MUST scores after CRT (P = 0.003) and before surgery (P = 0.035). Treatment completion was significantly associated with BWL (P = 0.028), MUST score (P = 0.013), and decreased serum albumin level (P = 0.001) after CRT. Regarding adverse events, MUST score before surgery (P = 0.009) and serum albumin level after CRT (P = 0.002) were significantly associated with diarrhea severity. Serum albumin level during CRT was associated with the onset of neutropenia (P = 0.005). No association was found between BWL and RFS.These findings suggest that malnutrition and changes in nutritional status are not only commonly observed after CRT, but also associated with treatment completion and adverse events.

Background and purpose: Preoperative 5-fluorouracil-based chemoradiotherapy is a standard treatment for locally advanced lower rectal cancer (LALRC). We performed a phase I study to develop a new regimen combining irinotecan and S-1. Materials and methods: Patients with LALRC (T3-4, N0-2) were studied. The radiation dose was 45 Gy in 25 fractions. S-1 (80 mg/m2/day) was administered on days 1–5, 8–12, 22–26, and 29–33. Irinotecan was administered on days 1, 8, 22, and 29. The dose of irinotecan was initially 60 mg/m2 (level 1). Surgery was performed 6–10 weeks after the chemoradiotherapy. Results: Twenty patients were enrolled, of whom 18 patients were analyzed. Dose-limiting toxicity (DLT) did not occur in the first 3 patients treated with irinotecan at 80 mg/m2 (level 2), but developed in 3 of the 6 patients who received irinotecan at 90 mg/m2 (level 3). Then DLT occurred in 3 other patients at level 2. At level 2 or 3, DLT comprised neutropenia, thrombocytopenia, and diarrhea. Level 2 was designated as the maximum tolerated dose, and level 1 as a recommended dose (RD). The pathological complete response rate was 28%, and the down-staging rate was 56%. Conclusions: Our results suggested that the RD of irinotecan when combined with preoperative S-1 and pelvic radiation was 60 mg/m2.

The feasibility of estimating patient-specific dose verification results directly from linear accelerator (linac) log files has been investigated for prostate cancer patients who undergo volumetric modulated arc therapy (VMAT). Twenty-six patients who underwent VMAT in our facility were consecutively selected. VMAT plans were created using Monaco treatment planning system and were transferred to an Elekta linac. During the beam delivery, dynamic machine parameters such as positions of the multi-leaf collimator and the gantry were recorded in the log files; subsequently, root mean square (rms) values of control errors, speeds and accelerations of the above machine parameters were calculated for each delivery. Dose verification was performed for all the plans using a cylindrical phantom with diodes placed in a spiral array. The gamma index pass rates were evaluated under 3%/3 mm and 2%/2 mm criteria with a dose threshold of 10%. Subsequently, the correlation coefficients between the gamma index pass rates and each of the above rms values were calculated. Under the 2%/2 mm criteria, significant negative correlations were found between the gamma index pass rates and the rms gantry angle errors (r = 0.64, p < 0.001) as well as the pass rates and the rms gantry accelerations (r = 0.68, p < 0.001). On the other hand, the rms values of the other dynamic machine parameters did not significantly correlate with the gamma index pass rates. We suggest that the VMAT quality assurance (QA) results can be directly estimated from the log file thereby providing potential to simplify patient-specific prostate VMAT QA procedure.

Concomitant intra-arterial infusion chemoradiotherapy (IA-CRT) has been used to treat locally advanced maxillary sinus squamous cell carcinoma (MSSCC) with positive outcomes. However, an optimal predictive prognostic factor for MSSCC treated with IA-CRT remains elusive. The aim of the present study was to assess the feasibility of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), including volumetric parameters, to predict the prognosis of MSSCC treated with IA-CRT. Twenty-four patients with newly diagnosed MSSCC receiving FDG-PET imaging before IA-CRT treatment were analyzed in this retrospective study. All patients underwent radiotherapy with a total tumor dose of 60–66 Gy in a conventional fractionation schedule, using three-dimensional conformal radiation therapy or intensity-modulated radiation therapy. Radiotherapy was performed concurrently with concurrent intra-arterial infusion chemotherapy (cisplatin). The IA-CRT response rate was 83.33%. The 1- and 3-year survival rates were 81.30% and 64.34%, respectively. The 1- and 3-year local failure-free rates were 57.21% and 40.96%, respectively. Local failure was significantly associated with poor survival (P = 0.0152). Further, clinical T staging clearly stratified local control outcomes among patients with clinical T3 or less, T4a, and T4b (P = 0.0312). Moreover, patients with stage T4b showed a significantly poorer local control compared with T3 or less (P = 0.0103). However, FDG-PET parameters provided no significant predictive information regarding treatment outcome. To conclude, pretreatment T stage predicts local control by IA-CRT, which is associated with survival.

We report here about a 59-year-old man with bone metastatic castration-resistant prostate cancer and biochemical progression, who underwent radium-223 (Ra-223) therapy, following previous treatment failure. Treatment response of osseous metastases was assessed with three 11C-choline positron emission tomography/computed tomography (PET/CT) scans at baseline, after three cycles for early monitoring, as well as after six cycles of radium-223 therapy. Pretreatment 11C-choline PET/CT showed multiple areas of increased focal activity in multiple cervical, thoracic, and lumbar vertebrae as well as in both ribs, right ileum, and left ischium. Second 11C-choline PET/CT after three cycles showed increasing tumor activity in the existing lesions and the new uptake spots of thoracic spine, both ribs and left ileum. Third 11C-choline PET/CT at the end of the therapy showed further progression with new lesions of thoratic spine, sacrum, right rib, and right ileum. In this case, 11C-choline PET/CT after three cycles for early monitoring could predict the therapeutic response to Ra-223.

To investigate the clinicopathological outcomes of patients with T4 lower rectal cancer treated using preoperative chemoradiotherapy with S-1 plus Irinotecan. Between 2005 and 2011, 35 patients with T4M0 lower rectal cancer, diagnosed initially as T4a in 12 and as T4b in 23, were treated with 45 Gy of radiotherapy concomitantly with S-1 plus Irinotecan. The median follow-up period was 50.6 months (range 2–123 months). A total of 32 patients (91.4 %) completed the radiotherapy and 26 (74.3 %) completed the full chemotherapy regimen. Radical surgery was then performed in 33 (94.3 %) of the 35 patients after the exclusion of two patients, who had macroscopic residual disease. The pathological diagnosis was downstaged from T4a to ypT0-3 in all 12 of those patients (100 %) and from T4b to ypT0-4a in 20 of those 23 patients (87.0 %). The tumor regression grade of 1a/1b/2/3 (complete response) was 10/8/15/2, respectively. In terms of long-term survival, the 5-year local relapse-free survival rate was 74.8 % and the recurrence-free survival rate was 52.0 %. This regimen may result in favorable downstaging. Moreover, in this series, pathological evidence of involvement of adjacent organs was rare following preoperative chemoradiotherapy, in the patients with disease diagnosed as T4b at the initial staging.

Introduction The aim of this study was to compare the short- and long-term outcomes between short-course radiotherapy with delayed surgery (SRT-delay) and a standard conventional chemoradiotherapy (CRT) regimen. Methods Two collaborating institutions adopted different regimens; the SRT-delay regimen was selected by Meiwa Hospital and the CRT regimen was selected by Hyogo College of Medicine. The inclusion criteria were T3 middle and low rectal cancer patients treated with radical surgery after preoperative therapy. The median follow-up period was 44 months (range, 12–85). Results From 2007 to 2013, 104 patients were treated using the SRT-delay regimen and 61 patients were treated using the CRT regimen. The pretreatment characteristics of the 2 groups were not significantly different. The sphincter-preserving rate (93.3%, 85.2%), T downstaging (37.5%, 37.7%), ypN(−) (74.0%, 67.2%), postoperative complications and the bowel, and urinary and sexual functioning of the SRT-delay regimen were noninferior to those of the CRT regimen. The 3-year local recurrence-free survival, recurrence-free survival, and overall survival in the SRT-delay and CRT groups were 90.6% and 90.6% ( P = .764), 83.8% and 78.3% ( P = .687) and 96.0% and 92.8% ( P = .833), respectively. Conclusion The SRT-delay regimen was noninferior in terms of the downstaging effect, and oncologic and functional outcomes compared with the CRT regimen for T3 middle and low rectal cancer.

The purpose of the present study was to determine the risk factors for developing thyroid disorders based on a dose–volume histograms (DVHs) analysis. Data from a total of 116 consecutive patients undergoing 3D conformal radiation therapy for head and neck cancers was retrospectively evaluated. Radiation therapy was performed between April 2007 and December 2010. There were 108 males and 8 females included in the study. The median follow-up term was 24 months (range, 1–62 months). The thyroid function was evaluated by measuring thyroid-stimulating hormone (TSH) and free thyroxine (FT4) levels. The mean thyroid dose, and the volume of thyroid gland spared from doses ≥10, 20, 30 and 40 Gy (VS10, VS20, VS30 and VS40) were calculated for all patients. The thyroid dose and volume were calculated by the radiotherapy planning system (RTPS). The cumulative incidences of hypothyroidism were 21.1% and 36.4% at one year and two years, respectively, after the end of radiation therapy. In the DVH analyses, the patients who received a mean thyroid dose

Polaprezinc (PZ), an antiulcer drug, has been reported to have antioxidant properties. The aim of the present study was to assess the feasibility and efficacy of administering PZ for radiation-induced mucositis in head and neck cancer patients. Patients with newly diagnosed head and neck cancer were enrolled in this prospective study. PZ was prepared as an oral rinse. The PZ oral rinse was used four times per day during the course of radiotherapy. Sequential changes in radiation mucositis were assessed during and after radiotherapy according to the Common Terminology Criteria for Adverse Events, version 3.0. Furthermore, a retrospective comparison analysis was performed to assess the efficacy of PZ for radiation-induced mucositis. A total of 32 patients were enrolled in the prospective study of the PZ oral rinse. Radiotherapy was performed up to a total dose of 60-66 Gy using a conventional schedule combined with chemotherapy. Of the 32 patients, 30 (93.8%) reported no complaints due to the PZ oral rinse. In addition, PZ was not associated with severe adverse effects. Among the patients who received PZ, grade 3 mucositis was observed in 29.0% based on the mucosal findings and in 39.3% based on the symptoms. In the patients who did not receive PZ, the incidence of grade 3 mucositis was 40.0% based on the mucosal findings and 60.7% based on the symptoms. Moreover, PZ promoted the recovery from mucositis caused by chemoradiotherapy and was not associated with reduced tumor response to radiotherapy. Therefore, the PZ oral rinse was well tolerated and proved to be efficient for the treatment of radiotherapy-induced oral mucositis.

Objectives/Hypothesis The purpose of this study was to estimate the efficacy of superselective arterial chemoradiotherapy for locally advanced carcinomas of the external auditory canal and middle ear. Study Design A retrospective study of clinical data for consecutive patients with locally advanced carcinomas of the external auditory canal and middle ear. Methods Thirteen patients with locally advanced carcinomas of the external auditory canal and middle ear (T3: one patient, T4: 12 patients) were reviewed. The median follow-up duration in the living patients was 33 months. The total dose of radiation therapy was 60 Gy using conventional fractionation. Four, five, or six courses of a superselective arterial infusion (cisplatin 50 mg) were given weekly. Results The overall survival and progression-free survival rates at 2 years, calculated by the Kaplan-Meier method, were 58.7% and 53.8%, respectively. No late-phase adverse effects due to chemoradiation and no adverse effects due to catheterization were observed. Conclusions These results suggest that superselective arterial chemoradiation can be a treatment option for locally advanced carcinomas of the external auditory canal and middle ear. Level of Evidence 4 Laryngoscope, 125:685–689, 2015

The purpose of this study was to investigate the prediction of mechanical error using DICOM-RT plan parameters for volumetric modulated arc therapy (VMAT). We created plans for gantry rotation arcs of 360° and 180° (full-arc and half-arc VMAT) for six maxillary sinus cancer cases using a Monaco treatment planning system, and delivered the doses with a linear accelerator. We calculated DICOM-RT plan parameters, including gantry, multileaf collimator (MLC) positions and Monitor Units (MU). We compared plans with regard to gantry angle per MU (degrees/MU) and MLC travel per MU (mm/MU) for each segment. Calculated gantry angle/MLC position speeds and errors were evaluated by comparison with the log file. On average, the half-arc VMAT plan resulted in 47% and 35% fewer degrees/MU and mm/MU than the full-arc VMAT plan, respectively. The root mean square (r.m.s.) gantry and MLC speeds showed a linear relationship with calculated degrees/MU and mm/MU, with coefficients of determination (R2) of 0.86 and 0.72, respectively. The r.m.s. gantry angle and MLC position errors showed a linear relationship with calculated degrees/MU and mm/MU with R2 of 0.63 and 0.76, respectively. Deviations from plan parameters were related to mechanical error for VMAT, and provided quantitative information without the need for VMAT delivery. These parameters can be used in the selection of treatment planning.

The aim of the present study was to determine the impact of obesity on radiation-induced gastrointestinal (GI) and genitourinary (GU) toxicity. The cases of 54 patients with prostate cancer, treated with three-dimensional conformal radiation therapy (RT), were reviewed. For each patient, the body mass index (BMI), distance between the prostate and rectum (D) on a computerised tomography scan and the dosimetric parameters of the rectum and bladder in the planning data of RT, were analyzed. GI and GU toxicity was assessed during and following RT. The results of the patients with a BMI of

We validated 3D radiochromic film dosimetry for volumetric modulated arc therapy (VMAT) using a newly developed spiral water phantom. The phantom consists of a main body and an insert box, each of which has an acrylic wall thickness of 3 mm and is filled with water. The insert box includes a spiral film box used for dose-distribution measurement, and a film holder for positioning a radiochromic film. The film holder has two parallel walls whose facing inner surfaces are equipped with spiral grooves in a mirrored configuration. The film is inserted into the spiral grooves by its side edges and runs along them to be positioned on a spiral plane. Dose calculation was performed by applying clinical VMAT plans to the spiral water phantom using a commercial Monte Carlo-based treatment-planning system, Monaco, whereas dose was measured by delivering the VMAT beams to the phantom. The calculated dose distributions were resampled on the spiral plane, and the dose distributions recorded on the film were scanned. Comparisons between the calculated and measured dose distributions yielded an average gamma-index pass rate of 87.0% (range, 91.2-84.6%) in nine prostate VMAT plans under 3 mm/3% criteria with a dose-calculation grid size of 2 mm. The pass rates were increased beyond 90% (average, 91.1%; range, 90.1-92.0%) when the dose-calculation grid size was decreased to 1 mm. We have confirmed that 3D radiochromic film dosimetry using the spiral water phantom is a simple and cost-effective approach to VMAT dose verification.

Background Although preoperative chemoradiotherapy exerts a destructive effect on positive lymph nodes, microscopic examination reveals different degrees of tumor regression. The aim of the present study is to investigate the impact of the radiation-induced regression of positive nodes on survival in patients with rectal cancer treated with preoperative chemoradiotherapy. Methods From 2001 to 2015, 229 patients with T3 rectal cancer underwent total mesorectal excision after preoperative chemoradiotherapy. The patients were classified into 3 groups according to their lymph node status: residual cancer cells in positive nodes (Group A), total regression of positive nodes after preoperative chemoradiotherapy with complete fibrosis (Group B), and the entire lymph node filled with lymph nodules and the absence of fibrosis (Group C). The survival of the 3 groups was compared, and a Cox model was used to evaluate the prognostic value of the regression of the positive nodes by preoperative chemoradiotherapy. Results Groups A, B, and C included 57, 18, and 154 patients, respectively. Group B showed significantly better overall survival than Group A (P = .041) and similar outcomes to Group C (P = .383). Among the patients with positive lymph nodes prior to treatment (Groups A and B), the total regression of the positive nodes after preoperative chemoradiotherapy was the only independent factor to be associated with good overall survival (hazard ratio; 6.26, 95% confidence interval; 1.28–113.0, P = .020). Conclusion Total regression of positive nodes by preoperative chemoradiotherapy improves the prognosis of patients with rectal cancer with positive lymph nodes prior to treatment.

The purpose of our study was to assess the feasibility of radiotherapy (RT) for locally advanced paranasal sinus carcinomas in late elderly patients (aged ≥75 years) from a single institution in Japan. From 2000 to 2015, we retrospectively analyzed 14 patients (11 maxillary and 3 ethmoid sinus carcinoma patients) who underwent RT for pathologically confirmed paranasal sinus carcinomas. RT was performed without unexpected cessations. Two patients, however, developed Grade 3 mucositis. The median follow-up duration was 13 months (range 2-54 months). The 1- and 2-year overall survival (OS) rates were 81.8 and 54.5 %, respectively. The local response rate after the initial treatment was 85.7 %. The 1- and 2-year progression-free survival (PFS) rates were 46.2 and 24.8 %, respectively. Univariate analysis of different clinicopathological parameters was conducted to identify associations with OS and PFS. We demonstrated that intensity modulated radiation therapy (IMRT) of >60 Gy with concomitant intra-arterial (cisplatin-based) infusion chemoradiotherapy led to improved OS and PFS rates, although no statistical significance was observed. Moreover, none of the squamous cell carcinoma (SCC) patients who received 33 fractions of 66 Gy in IMRT died during the median follow-up period of 13 months (range 12-25 months). In conclusion, RT with concomitant intra-arterial (cisplatin-based) infusion chemoradiotherapy can be considered an effective, well-tolerated, and feasible treatment option for late elderly patients with paranasal sinus carcinomas. In addition, >60 Gy of RT in IMRT led to improved survival outcomes in elderly paranasal sinus carcinoma patients.

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. 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. 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. 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.

We compared the efficiency and accuracy of full-arc and half-arc volumetric-modulated arc therapy (VMAT) delivery for maxillary cancer. Plans for gantry rotation angles of 360° and 180° (full-arc and half-arc VMAT) were created for six maxillary cancer cases with the Monaco treatment planning system, and delivered using an Elekta Synergy linear accelerator. Full-arc and half-arc VMAT were compared with regard to homogeneity index (HI), conformity index (CI), mean dose to normal brain, total monitor units (MU), delivery times, root mean square (r.m.s.) gantry accelerations (°/s(2)), and r.m.s. gantry angle errors (°). The half-arc VMAT plans achieved comparable HI and CI to the full-arc plans. Mean doses to the normal brain and brainstem with the half-arc VMAT plans were on average 16% and 17% lower than those with the full-arc VMAT plans. For other organs at risk (OARs), no significant DVH differences were observed between plans. Half-arc VMAT resulted in 11% less total MU and 20% shorter delivery time than the full-arc VMAT, while r.m.s. gantry acceleration and r.m.s. gantry angle error during half-arc VMAT delivery were 30% and 23% less than those during full-arc VMAT delivery, respectively. Furthermore, the half-arc VMAT plans were comparable with the full-arc plans regarding dose homogeneity and conformity in maxillary cancer, and provided a statistical decrease in mean dose to OAR, total MU, delivery time and gantry angle error. Half-arc VMAT plans may be a suitable treatment option in radiotherapy for maxillary cancer.

The ongoing structure of radiation oncology in Japan in terms of equipment, personnel, patient load and geographic distribution was evaluated in order to radiation identify and improve any deficiencies. A questionnaire-based national structure survey was conducted from March 2010 to January 2011 by the Japanese Society for Therapeutic Radiology and Oncology (JASTRO). These data were analyzed in terms of the institutional stratification of the Patterns of Care Study (PCS). The total numbers of new cancer patients and total of cancer patients (new and repeat) treated with radiation in 2009 were estimated at 201,000 and 240,000, respectively. The type and numbers of systems in actual use consisted of Linac (816), telecobalt (9), Gamma Knife (46), (60)Co remote afterloading system (RALS) (29) and (192)Ir RALS systems (130). The Linac systems used dual energy function for 586 (71.8%), 3DCRT for 663 (81.3%) and IMRT for 337 units (41.3%). There were 529 JASTRO-certified radiation oncologists (ROs), 939.4 full-time equivalent (FTE) ROs, 113.1 FTE medical physicists and 1836 FTE radiation therapists. The frequency of interstitial radiation therapy use for prostate and of intensity-modulated radiotherapy increased significantly. PCS stratification can clearly identify the maturity of structures based on their academic nature and caseload. Geographically, the more JASTRO-certified physicians there were in a given area, the more radiation therapy tended to be used for cancer patients. In conclusion, the Japanese structure has clearly improved during the past 19 years in terms of equipment and its use, although a shortage of manpower and variations in maturity disclosed by PCS stratification remained problematic in 2009.

The prognosis of advanced esophageal cancer patients is poor. Trimodality therapy of surgical resection plus neoadjuvant chemoradiotherapy (CRT) has been developed to improve survival through locoregional control, leading to prevention of micrometastasis. We investigated whether or not neoadjuvant CRT led to survival benefits in TNM stage II/III esophageal cancer patients. We retrospectively reviewed 62 patients with stage II or III esophageal squamous cell carcinoma (ESCC) treated with neoadjuvant CRT. All patients received esophagectomy 4-7 weeks after CRT consisting of 40 Gy irradiation and chemotherapy (5-FU, 500 mg/m2/day, days 1-5 and cisplatin, 10-20 mg/body, days 1-5). Clinical response and survival rates were analyzed using Kaplan-Meier methods, with p0.05 considered as significant. The clinical effect rate of CRT for both primary tumors and metastatic nodes was 82.3%. Operative and hospital mortality rates were 1.65 and 6.5%, respectively. The 3-year overall survival (OS) and disease-free survival (DFS) rates were 52.6 and 49.2%, respectively. A significant difference was noted between stages II and III for both OS and DFS. The 5-year OS rates were 64.2% for stage II, 33.1% for stage III (T4 and non-T4) and 46.9% for stage III (non-T4 only) patients. The depth of tumor invasion (T3 vs. T4), resectability (R0 vs. R1, R2), lymph node metastasis (positive vs. negative), and the effect of CRT were proven to be independent prognostic factors for univariate analysis, with resectability and the effect of CRT for multivariate analysis. These data suggest that CRT in stage II/III (non-T4) ESCC patient contributed to tumor shrinkage, leading to higher resectability and longer survival. Neoadjuvant CRT appears to be a promising option for these patients.

HLA-haploidentical hematopoietic stem cell transplantation (haplo-SCT) in HLA-homozygous patients is accompanied by HLA mismatches only in the host-versus-graft vector, and thus theoretically could be performed with standard graft-versus-host disease (GVHD) prophylaxis. However, the risk of GVHD remains uncertain, and graft failure could be a problem. In this study, we assessed nine HLA-homozygous patients who underwent haplo-SCT. Preparative treatment was cyclophosphamide/total body irradiation-based regimen in five patients, fludarabine/busulfan-based regimen in two, and other regimens in two. GVHD prophylaxis consisted of cyclosporine and methotrexate in seven patients, cyclosporine and mycophenolate mofetil in one, and cyclosporine alone in one. Seven patients achieved neutrophil engraftment and platelet recovery. The median times to neutrophil engraftment and platelet recovery were 15 and 44 days, respectively. Two patients developed graft failure, including one who achieved engraftment with a second SCT from the same donor. Grade II GVHD was observed in half of the evaluable patients; grades III and IV were not observed. Two patients died from treatment-related causes. Five patients were alive after a median follow-up period of 563 days. The probability of overall survival at 5 years was 65 %. These findings may serve as a rationale for considering haplo-SCT as a treatment option for HLA-homozygous patients.

The purpose of the present study was to establish an experimental rat model for late radiation proctitis, and to examine the assessment strategy for late radiation proctitis. A total of 57 Wistar rats were used. Fourty-five of the rats were exposed to selective rectal irradiation with a single fraction of 25 Gy. These rats were sacrificed at the 4(th), 12(th), 24(th), and 37(th) week following irradiation. The remaining 12 rats comprised the control group without irradiation. The rectal mucosa of each rat was evaluated macroscopically and pathologically. The number of vessels in the rectal mucosa was counted microscopically. In addition, the vascular stenosis was evaluated. In the results, the degree of clinical and macroscopic findings decreased following acute proctitis and developed later. In the pathological examination, mucosal changes and microangiopathy were followed up, as well. The absolute number of vessels in the rectum was the greatest at the 12(th) week following irradiation and was the lowest in the control group. The severity of the microangiopathy was also well evaluated. To conclude, we established an animal experimental model of late radiation proctitis, and also established an assessment strategy to evaluate objectively the severity of late radiation proctitis with focusing on microangiopathy using an animal experimental model. This model can be used as an animal experimental model of radiation-induced microangiopathy.

Purpose The purpose of the present study was to standardize the experimental rat model of radiation proctitis and to examine the efficacy of polaprezinc on radiation proctitis. Methods and Materials A total of 54 female Wistar rats (5 weeks old) were used. The rats were divided into three groups: those treated with polaprezinc (PZ+), those treated with base alone, exclusive of polaprezinc (PZ−), and those treated without any medication (control). All the rats were irradiated to the rectum. Polaprezinc was prepared as an ointment. The ointment was administered rectally each day after irradiation. All rats were killed on the 10th day after irradiation. The mucosal changes were evaluated endoscopically and pathologically. The results were graded from 0 to 4 and compared according to milder or more severe status, as applicable. Results According to the endoscopic findings, the proportion of mild changes in the PZ+, PZ−, and control group was 71.4%, 25.0%, and 14.3% respectively. On pathologic examination, the proportion of low-grade findings in the PZ+, PZ−, and control group was 80.0%, 58.3%, and 42.9% for mucosal damage, 85.0%, 41.7%, and 42.9% for a mild degree of inflammation, and 50.0%, 33.3%, and 4.8% for a shallow depth of inflammation, respectively. The PZ+ group tended to have milder mucosal damage than the other groups, according to all criteria used. In addition, significant differences were observed between the PZ+ and control groups regarding the endoscopic findings, degree of inflammation, and depth of inflammation. Conclusions This model was confirmed to be a useful experimental rat model for radiation proctitis. The results of the present study have demonstrated the efficacy of polaprezinc against acute radiation-induced rectal disorders using the rat model.

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. 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. 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. 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.

To evaluate the ongoing structure of radiation oncology in Japan in terms of equipment, personnel, patient load, and geographic distribution to identify and improve any deficiencies.A questionnaire-based national structure survey was conducted from March to December 2008 by the Japanese Society of Therapeutic Radiology and Oncology (JASTRO). These data were analyzed in terms of the institutional stratification of the Patterns of Care Study.The total numbers of new cancer patients and total cancer patients (new and repeat) treated with radiation in 2007 were estimated at 181,000 and 218,000, respectively. There were 807 linear accelerator, 15 telecobalt, 46 Gamma Knife, 45 (60)Co remote-controlled after-loading, and 123 (192)Ir remote-controlled after-loading systems in actual use. The linear accelerator systems used dual-energy function in 539 units (66.8%), three-dimensional conformal radiation therapy in 555 (68.8%), and intensity-modulated radiation therapy in 235 (29.1%). There were 477 JASTRO-certified radiation oncologists, 826.3 full-time equivalent (FTE) radiation oncologists, 68.4 FTE medical physicists, and 1,634 FTE radiation therapists. The number of interstitial radiotherapy (RT) administrations for prostate, stereotactic body radiotherapy, and intensity-modulated radiation therapy increased significantly. Patterns of Care Study stratification can clearly identify the maturity of structures based on their academic nature and caseload. Geographically, the more JASTRO-certified physicians there were in a given area, the more RT tended to be used for cancer patients.The Japanese structure has clearly improved during the past 17 years in terms of equipment and its use, although a shortage of personnel and variations in maturity disclosed by Patterns of Care Study stratification were still problematic in 2007.

Polaprezinc (PZ) suppositories have been used for radiation proctitis in our hospital.In this study,we established methods to evaluate the quality of hospital-prepared PZ suppositories and investigated their stability.As PZ is dissociated at an acidic pH but not at a medium pH,the release of PZ from the suppository was carried out using chelatometric titration in weakly acidic buffer solutions (pH 3,pH 4,and pH 5).As the release of PZ from the suppository was fastest in the buffer solution at pH 3,we used this pH for the release test for PZ.Conducting this test in the stability investigation showed that the amount of PZ released from the suppository after 84 days was the same as that immediately after manufacture.We also examined the clinical efficacy of the PZ suppository in 5 patients with radiation proctitis,finding that efficacy was satisfactory in 3 patients.These results indicated that the PZ suppository is a good treatment for radiation proctitis.

聴器癌に対する超選択的動注化学療法併用放射線治療の治療成績を報告する。対象は2003年3月から2009年7月にかけて超選択的動注化学療法併用放射線治療を施行した聴器癌15例。男性7例，女性8例。扁平上皮癌13例，未分化癌1例，腺癌1例。Moodyらの分類によるT分類は，T1：1例，T2：1例，T3：1例，T4：12例。経過観察期間は，4～44ヶ月（中央値14ヶ月）。放射線治療は1日1回2Gyで40～60Gyを施行。動注化学療法は，大腿動脈アプローチのセルジンガー法でシスプラチン単剤を1回50mg/bodyで週1回を4～5回投与した。中和剤としてチオ硫酸ナトリウムの点滴と血管炎予防目的にプレドニン20mgの動注を行なった。Kaplan-Meier法による2年粗生存率は73.4%，2年無増悪生存率は53.3%であった。遷延する皮下の炎症を1例に見られたが，重篤な晩期有害事象は出現していない。聴器癌に対する超選択的動注化学療法併用放射線治療の有効性が示唆された。今後さらに長期の経過観察が必要と考える。

The structure of radiation oncology in designated cancer care hospitals in Japan was investigated in terms of equipment, personnel, patient load, and geographic distribution, and compared with the structure in other radiotherapy facilities.The Japanese Society of Therapeutic Radiology and Oncology (JASTRO) conducted a questionnaire survey about the national structure of radiation oncology in 2005. In the current study, the structures of 326 designated cancer care hospitals and the other 386 radiotherapy facilities in Japan were compared.Designated cancer care hospitals accounted for 45.3% of all radiotherapy facilities. The patterns of equipment and personnel in designated cancer care hospitals and the other radiotherapy facilities were as follows: linear accelerators/facility, 1.2 and 1.0; dual-energy function, 73.1% and 56.3%; three-dimensional conformal radiotherapy function, 67.5% and 52.7%; intensity-modulated radiotherapy function, 30.0% and 13.9%; annual number of patients/linear accelerator, 289.7 and 175.1; (192)Ir remote-controlled afterloading systems, 27.6% and 8.6%; and average number of full-time equivalent radiation oncologists/facility, 1.4 and 0.9 (P0.0001). There were significant differences in equipment and personnel between the two types of facilities. Annual patient loads/full-time equivalent radiation oncologist in the designated cancer care hospitals and the other radiotherapy facilities were 252 and 240. Geographically, the number of designated cancer care hospitals was associated with the population, and the number of JASTRO-certified physicians was associated with the number of patients undergoing radiotherapy.The Japanese structure of radiation oncology in designated cancer care hospitals was more mature than that in the other radiotherapy facilities in terms of equipment, although a shortage of personnel still exists. The serious understaffing problem in radiation oncology should be corrected in the future.

目的．切除可能悪性胸膜中皮腫の手術成績向上のためには集学的治療が必要であるが，その至適治療法は確立していない．術前化学療法，手術および術後放射線治療からなる集学的治療のコンプライアンスと安全性を検証するために前向き臨床試験立案を計画した．研究計画．文部科学省科学技術振興調整費"アスベスト関連疾患への総括的取り組み"の一環として，臨床試験が計画された．結果．多施設共同のfeasibility試験が承認され，現在開始された．適格症例は，シスプラチンとペメトレキセドによる化学療法を3コース行った後に胸膜肺全摘除術と術後の放射線治療により治療される．主要評価項目は完全切除率と治療関連死亡率であり，向こう3年間で40例の適格症例の本臨床試験への参加が期待されている．結論．本臨床試験の完遂により切除可能胸膜中皮腫に対する集学的治療のfeasibilityが確認されれば，引き続いて臨床的有効性を検証する第II相試験へ進む予定である．

The purpose of this study was to investigate the clinical value of diffusion-weighted (DW) magnetic resonance imaging (MRI) as a predictor of tumor response in patients receiving neoadjuvant chemoradiotherapy (NA-CRT) for rectal cancer (RC) through measurement of the apparent diffusion coefficient (ADC) value in each tumor. Neoadjuvant radiotherapy with a total dose of 45 Gy in 25 fractions was performed in all 16 patients with RC, combined with irinotecan and S-1. MRI was performed before and after NA-CRT. Multiple factors were assessed to predict the pathological response to NA-CRT. The pathological response rate was determined in 9 patients (56.3%). Statistical analyses indicated that the ADC value prior to NA-CRT was significantly lower in patients with a better response to NA-CRT (P=0.023). A cut-off value of 0.750×10−3 mm2/sec obtained by a receiver operating characteristic curve analysis indicated a sensitivity of 77.8% and specificity of 85.7% for pathological responders to NA-CRT. In addition, the patients with lower ADC values exhibited a greater pathological response to NA-CRT (P=0.041). In conclusion, the ADC value of MRI of RC patients treated with NA-CRT followed by surgery may provide valuable information to predict the response to NA-CRT.

The aim of this study was to compare the pathological response of mesorectal positive nodes between short-course chemoradiotherapy with delayed surgery (SCRT-delay) and long-course chemoradiotherapy (LC-CRT) in patients with rectal cancer. The resected primary tumor specimens following the two different approaches were assessed utilizing the tumor regression grade (TRG 0–4), and each positive lymph node was assessed according to the lymph node regression grade (LRG 1–3), with TRG 4 and LRG 3 indicating total regression. The lymph node sizes were measured to elucidate any correlation with LRG scores. Seventy-four patients with ypN-positive rectal cancer had 220 positive lymph nodes following the SCRT-delay, and 48 patients had 141 positive lymph nodes following the LC-CRT. The distribution of LRG 1/2/3 in the two groups was 123/72/25 and 60/31/50 (p

To evaluate the safety and efficacy of induction SOX (S-1 + oxaliplatin) ± cetuximab chemotherapy followed by short-course chemoradiotherapy and surgery in patients with poor-risk locally advanced rectal cancer. We enrolled eligible patients with poor-risk rectal cancer defined as T3 lower rectal cancer with mesorectal fascia involvement, T4a or T4b tumors or cases with lateral lymph node swelling. The primary endpoint was a pathological complete response (pCR), and the secondary endpoints were the objective response rate (ORR) and the pathological high response rate (Grade 2 plus 3). Twenty eligible patients were enrolled. The majority (75.0 %, 15/20) of the patients completed four cycles of induction chemotherapy, and all patients completed the radiotherapy (25 Gy/10 fractions/5 days). The global rate of Grade 3–4 toxicities was 30.0 % (6/20 patients). The ORRs were 85.0 % (17/20) and 95.0 % (19/20) in the patients who underwent R0 and R1 resection, respectively. The pathological high response rate was 70.0 % (14/20) and the pCR was 10.0 % (2/20). The regimen of induction SOX (S-1 + oxaliplatin) ± cetuximab chemotherapy followed by short-course chemoradiotherapy is safe and is associated with good tumor regression in patients with poor-risk locally advanced rectal cancer.

5-Fluorouracil-based chemotherapy is considered to be a radiosensitizer; however, conventional short-course radiotherapy combined with chemotherapy is generally thought to not be feasible because of the prevalence of side effects.The aim of this study was to evaluate the feasibility of modified short-course radiotherapy combined with a chemoradiosensitizer for T3 rectal cancer.This study was retrospective in nature and used a prospectively collected database.Patients with T3 rectal cancer located below the peritoneum reflection were selected.A total dose of 25 Gy of radiotherapy was administered in 10 fractions of 2.5 Gy each for 5 days. Radiotherapy was performed with S-1 as a radiosensitizer from day 1 to day 10. Surgery was targeted to be performed 4 weeks after radiotherapy.The morbidity, sphincter-preserving rate, anal function, and long-term outcomes were assessed.All patients (n = 170) completed the radiotherapy regimen and 166 (97.6%) completed the combination regimen with chemotherapy. A total of 149 patients (87.6%) had sphincter-preserving surgery (double stapling technique (DST), 58 patients; intersphincteric resection (ISR), 91 patients), and postoperative complications were relatively mild (anastomotic leakage, 15.4%; intra-abdominal infection, 8.2%). Among those undergoing sphincter preserving surgery, the 5-year local relapse-free survival rate was 94.3% in the DST group, and 89.8% in the ISR group. With respect to the anal function, the Wexner score the first year after stoma closure for the double-stapling technique group was 6 and that for intersphincteric resection was 15; however, the score for the intersphincteric resection group was improved to 8 at 4 years after stoma closure.This study had limitations because it was an uncontrolled, 1-arm, retrospective review with a small sample size.Modified short-course radiotherapy combined with chemoradiosensitizer is a feasible approach for treating T3 rectal cancer. With the use of the short-course approach, efforts to reduce the incidence of side effects by appropriately prolonging the waiting period enable the administration of combination treatment with short-course radiotherapy and chemotherapy.