Dosimetric variations due to interfraction organ deformation in cervical cancer brachytherapy

We quantitatively estimated dosimetric variations due to interfraction organ deformation in multi-fractionated high-dose-rate brachytherapy (HDRBT) for cervical cancer using a novel surface-based non-rigid deformable registration. As the number of consecutive HDRBT fractions increased, simple addition of dose-volume histogram parameters significantly overestimated the dose, compared with distribution-based dose addition.

Combination of 5α-reductase inhibitor with combined androgen blockade (CAB) as a novel cytoreductive regimen before prostate brachytherapy: Ultra-CAB

We report a first case of using a 5α-reductase inhibitor (5ARI) and combined androgen blockade (CAB) as a cytoreductive regimen before prostate brachytherapy. Prostate volume reduction with CAB is limited to approximately 40% in most cases, making it difficult to meet anatomical constraints to perform these procedures in cases with large prostate volume. With the added administration of 5ARI, further volume reduction can be expected. Here, we describe this cytoreductive regimen used in a 63 year-old prostate cancer patient who became eligible to receive brachytherapy after dutasteride (0.5 mg daily) was added to CAB and prostate volume reduction of 57% was achieved.

A dose-response analysis of biochemical control outcomes after (125)I monotherapy for patients with favorable-risk prostate cancer

PURPOSE

To define the optimal dose for (125)I prostate implants by correlating postimplantation dosimetry findings with biochemical failure and toxicity.

METHODS AND MATERIALS

Between 2003 and 2009, 683 patients with prostate cancer were treated with (125)I prostate brachytherapy without supplemental external beam radiation therapy and were followed up for a median time of 80 months. Implant dose was defined as the D90 (the minimal dose received by 90% of the prostate) on postoperative day 1 and 1 month after implantation. Therefore, 2 dosimetric variables (day 1 D90 and day 30 D90) were analyzed for each patient. We investigated the dose effects on biochemical control and toxicity.

RESULTS

The 7-year biochemical failure-free survival (BFFS) rate for the group overall was 96.4% according to the Phoenix definition. A multivariate analysis found day 1 D90 and day 30 D90 to be the most significant factors affecting BFFS. The cutoff points for day 1 D90 and day 30 D90, calculated from ROC curves, were 163 Gy and 175 Gy, respectively. By use of univariate analysis, various dosimetric cutoff points for day 30 D90 were tested. We found that day 30 D90 cutoff points from 130 to 180 Gy appeared to be good for the entire cohort. Greater D90s were associated with an increase in late genitourinary or gastrointestinal toxicity ≥ grade 2, but the increase was not statistically significant.

CONCLUSIONS

Improvements in BFFS rates were seen with increasing D90 levels. Day 30 D90 doses of 130 to 180 Gy were found to serve as cutoff levels. For low-risk and low-tier intermediate-risk prostate cancer patients, high prostate D90s, even with doses exceeding 180 Gy, achieve better treatment results and are feasible.

Successful treatment of metastatic rhabdomyosarcoma with radiochemotherapy and allogeneic hematopoietic stem cell transplantation

We report a case of a 21-year-old man with alveolar rhabdomyosarcoma primarily in the right hand with lymph node, lung, bone and bone marrow metastases. Complete remission was achieved after intensive chemotherapy and radiotherapy of the primary and metastatic sites, followed by allogeneic peripheral blood stem cell transplantation with reduced-intensity conditioning from a single HLA-DR locus-mismatched mother. The patient remained relapse-free for 41 months after the diagnosis. Considering that the conventional treatment for rhabdomyosarcoma with multiple risk factors (old age, bone or bone marrow involvement, unfavorable primary sites and ≥ 3 metastases) is associated with a poor prognosis (5% probability of a 3-year event-free survival), the graft-versus-tumor effect may have contributed to his sustained relapse-free survival. Allogeneic hematopoietic stem cell transplantation for rhabdomyosarcoma should be done by experienced clinical oncologists on properly designed controlled trials.

Postmortem radiation safety and issues pertaining to permanent prostate seed implantation in Japan

PURPOSE

If a prostate cancer patient treated with (125)I brachytherapy dies within 12 months after the treatment, prostate removal before cremation is recommended to avoid problems related to radioactivity in the ashes, such as inhalation of airborne particulate matter by crematorium staff or nearby residents. To provide guidance for such cases, a manual prepared under the editorial supervision of several professional associations was issued in 2008 in Japan. Herein, we investigated the incidence and causes of death, and the actions taken subsequent to death, among prostate cancer patients who died within 12 months after (125)I brachytherapy over a 10-year period in Japan; and we compared the results before and after the manual was issued.

METHODS AND MATERIALS

Data extracted from the Japan Radioisotope Association database for the period from September 2003 to the end of December 2013 were used.

RESULTS

Of 27,976 patients who underwent (125)I brachytherapy during the specified period, 79 died within 12 months after implantation, including 3 who died in the 2011 earthquake and tsunami. The prostate and brachytherapy source were retrieved at autopsy from 69 of the 79 patients. Autopsy could not be performed on the other 10 patients, 2 of whom died in the earthquake. Autopsy and retrieval of the brachytherapy source were significantly more common after issuance of the manual than before (22/28 cases before; 47/49 cases after; p=0.021).

CONCLUSION

In most cases of early death after (125)I brachytherapy in Japan, the brachytherapy source was retrieved.

Nationwide Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation (J-POPS)

BACKGROUND

To evaluate the safety and efficacy of brachytherapy with permanent iodine-125 seed implantation (PI) for prostate cancer. The nationwide Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation (J-POPS) has continued since July 2005. This manuscript presents the rationale, J-POPS study design, and the characteristics of initial participants enrolled in this study from July 2005 to June 2007.

METHODS

All participants were treated with PI in accordance with the American Brachytherapy Society recommendations. The primary outcome measure was biochemical progression-free survival. Progression-free survival, overall survival, cause-specific survival, longitudinal changes in health-related quality of life, disease-specific quality of life, the International Prostate Symptom Score, and the incidence of adverse events were also investigated as secondary outcome measurements.

RESULTS

Overall, 6,927 patients were enrolled by the end of 2010, that is approximately 40 % of all cases treated around the country. During the first 2 years, 2,354 participants were enrolled and 2,339 were actually treated with PI. The age range of participants was 45 to 89 years (median 69 years) and their risk classifications were 1,037 (44.3 %) at low risk, 1,126 (48.1 %) at intermediate risk, and 134 (5.7 %) at high risk, in addition to 16 participants whose classification was unknown. Of all patients, 76.6 % were treated with PI without external beam radiation therapy and 49.3 % received neoadjuvant hormone therapy.

CONCLUSIONS

The J-POPS, a nationwide prospective cohort study that enrolled approximately 40 % of all PI cases in Japan, will provide highly reliable evidence, including outcomes and quality of life, after long-term follow-up.

Combined brachytherapy and external beam radiotherapy without adjuvant androgen deprivation therapy for high-risk prostate cancer

Background

To report the outcomes of patients treated with combined iodine-125 (I-125) brachytherapy and external beam radiotherapy (EBRT) for high-risk prostate cancer.

Methods

Between 2003 and 2009, I-125 permanent prostate brachytherapy plus EBRT was performed for 206 patients with high-risk prostate cancer. High-risk patients had prostate-specific antigen ≥ 20 ng/mL, and/or Gleason score ≥ 8, and/or Stage ≥ T3. One hundred and one patients (49.0%) received neoadjuvant androgen deprivation therapy (ADT) but none were given adjuvant ADT. Biochemical failure-free survival (BFFS) was determined using the Phoenix definition.

Results

The 5-year actuarial BFFS rate was 84.8%. The 5-year cause-specific survival and overall survival rates were 98.7% and 97.6%, respectively. There were 8 deaths (3.9%), of which 2 were due to prostate cancer. On multivariate analysis, positive biopsy core rates and the number of high-risk factors were independent predictors of BFFS. The 5-year BFFS rates for patients in the positive biopsy core rate <50% and ≥50% groups were 89.3% and 78.2%, respectively (p = 0.03). The 5-year BFFS rate for patients with the any single high-risk factor was 86.1%, compared with 73.6% for those with any 2 or all 3 high-risk factors (p = 0.03). Neoadjuvant ADT did not impact the 5-year BFFS.

Conclusions

At a median follow-up of 60 months, high-risk prostate cancer patients undergoing combined I-125 brachytherapy and EBRT without adjuvant ADT have a high probability of achieving 5-year BFFS.

Phase I study of neoadjuvant chemoradiotherapy with S-1 plus biweekly cisplatin for advanced gastric cancer patients with lymph node metastasis: -KOGC04-

Background

In patients with highly advanced gastric cancer, the recurrence rate remains high and the prognosis disappointing. We previously reported a phase I study of a neoadjuvant chemoradiotherapy of S-1 plus weekly cisplatin. Although adequate safety and efficacy were reported, myelosuppression was frequently observed, leading to treatment delay in several cases. To decrease toxicity and improve efficacy, we planned a phase I study with a modified chemotherapy regimen with biweekly cisplatin.

Methods

Patients with advanced gastric cancer and lymph node metastasis who were treated by our institution between 2011 and 2012 were eligible for inclusion. The initial chemoradiotherapy schedule consisted of 6 weeks of S-1 orally administered on days 1–15 with an escalating dose of cisplatin administered on days 1 and 15. The starting dose (level 1) of cisplatin was 15 mg/m², the second dose (level 2) was 20 mg/m², and the third dose (level 3) was 25 mg/m². Radiation of 40 Gy was administered in 20 fractions. After initial chemoradiotherapy, one cycle of combination chemotherapy with S-1 plus cisplatin was delivered. The second cycle was 42 days in duration and included S-1 administered on days 1–29 plus biweekly cisplatin administered on days 1, 15, and 29. After neoadjuvant treatment, a curative gastrectomy with extended (D2) lymph node dissection was planned.

Results

Nine patients were enrolled. At level 3, one patient had dose-limiting grade 3 diarrhea. Another patient experienced grade 3 nausea and intended to discontinue the treatment. Overall, because 2 of 3 patients experienced dose-limiting toxicity at level 3, we confirmed level 3 (Cisplatin 25 mg/m²) as the maximum tolerated dose and level 2 (Cisplatin 20 mg/m²) as the recommended dose (RD). The response rate was 78%, and 8 patients underwent curative gastrectomy. Resected specimens showed a histological response in 6 patients (75%), including one with a pathological complete response.

Conclusions

In this phase I trial, RD of cisplatin was identified as 20 mg/m². Generally, S-1 plus biweekly cisplatin can be given safely with concurrent radiation. We have initiated a multicenter phase II trial to further confirm the efficacy and safety of this approach.

Trial registration

UMIN000008941

Comparison of the repair of potentially lethal damage after low- and high-LET radiation exposure, assessed from the kinetics and fidelity of chromosome rejoining in normal human fibroblasts

Potentially lethal damage (PLD) and its repair (PLDR) were studied in confluent human fibroblasts by analyzing the kinetics of chromosome break rejoining after X-ray or heavy-ion exposures. Cells were either held in the non-cycling G0 phase of the cell cycle for 12 h, or forced to proliferate immediately after irradiation. Fusion premature chromosome condensation (PCC) was combined with fluorescence in situ hybridization (FISH) to study chromosomal aberrations in interphase. The culture condition had no impact on the rejoining kinetics of PCC breaks during the 12 h after X-ray or heavy-ion irradiation. However, 12 h after X-ray and silicon irradiation, cycling cells had more chromosome exchanges than non-cycling cells. After 6 Gy X-rays, the yield of exchanges in cycling cells was 2.8 times higher than that in non-cycling cells, and after 2 Gy of 55 keV/μm silicon ions the yield of exchanges in cycling cells was twice that of non-cycling cells. In contrast, after exposure to 2 Gy 200-keV/μm or 440-keV/μm iron ions the yield of exchanges was similar in non-cycling and cycling cells. Since the majority of repair in G0/G1 occurs via the non-homologous end joining process (NHEJ), increased PLDR in X-ray and silicon-ion irradiated cells may result from improved cell cycle-specific rejoining fidelity through the NHEJ pathway, which is not the case in high-LET iron-ion irradiated cells.

Outcomes following iodine-125 prostate brachytherapy with or without neoadjuvant androgen deprivation

PURPOSE

To report the biochemical failure-free survival (BFFS), cause-specific survival (CSS), and overall survival (OS) outcomes of patients treated with iodine-125 (I-125) brachytherapy for clinically localized prostate cancer.

METHODS AND MATERIALS

Between 2003 and 2009, I-125 permanent prostate brachytherapy without supplemental external-beam radiotherapy was performed for 663 patients with low-risk and low-tier intermediate-risk (defined as organ-confined disease, PSA <10ng/mL, and Gleason score 3+4 with biopsy positive core rate <33%) prostate cancer. Early in the study period, the preplanning method was used in the first 104 patients, and later the real-time planning method was used. Biochemical failure was determined using the American Society for Therapeutic Radiology Oncology (ASTRO) and Phoenix definitions.

RESULTS

The 7-year BFFS rates for the ASTRO and Phoenix definitions were 96.1% and 95.9%, respectively. The corresponding BFFS rates by risk group were 97.6% and 96.7% for low-risk, and 91.8% and 93.6% for low-tier intermediate-risk disease (p=0.007 and 0.08, respectively). The median times to biochemical failure in those who failed were 29.5 and 43.9months according to the ASTRO and Phoenix definitions, respectively. The 7-year CSS and OS were 99.1% and 96.4%. There was no significant difference in CSS or OS between the low-risk and low-tier intermediate-risk groups. In multivariate Cox regression analysis, risk group and prostate D90 were independent predictors of BFFS for the ASTRO definition, while only the prostate D90 was significant for the Phoenix definition.

CONCLUSION

I-125 prostate brachytherapy results in excellent 7-year BFFS, CSS, and OS for low-risk and low-tier intermediate-risk prostate cancer.

Continuous low-dose irradiation by I-125 seeds induces apoptosis of gastric cancer cells regardless of histological origin

The efficacy of conventional radiation therapy for gastric cancer is controversial. In this study, we evaluated the in vitro and in vivo effects of continuous low-dose-rate irradiation by I-125 seeds on different histological types of gastric cancer cell lines. Three human gastric cancer cell lines (MKN74, MKN45, and NUGC4) were treated with or without continuous low-dose irradiation by I-125 seeds in vitro and in vivo. Cell viability, apoptosis, caspase-3 assay, and cell-cycle distribution were examined in vitro. Body weight and tumor volumes of BALB/c nude mice bearing MKN74, MKN45, and NUGC4 gastric cancer xenografts were measured, and in vivo cell proliferation and apoptosis assays were performed by Ki67 and TUNEL staining, respectively. Continuous low-dose-rate irradiation by I-125 seeds reduced cell viability and induced cell apoptosis through the activation of caspase-3, and led to the accumulation of cells in the G 2/M phase in vitro. It also suppressed the growth of gastric cancer xenografts in nude mice, while inhibiting cell proliferation and inducing apoptosis as demonstrated by Ki67 and TUNEL staining. Therefore, our data suggest that continuous low-dose-rate irradiation by I-125 seeds could be a promising new option for gastric cancer treatment, regardless of histological origin.

A newly introduced comprehensive consultation fee in the national health insurance system in Japan: a promotive effect of multidisciplinary medical care in the field of radiation oncology--results from a questionnaire survey

OBJECTIVE

The consultation fee for outpatient radiotherapy was newly introduced in the national health insurance system in Japan in April 2012. We conducted a survey on the use of this consultation fee and its effect on clinical practices.

METHODS

The health insurance committee of the Japanese Society of Therapeutic Radiology and Oncology conducted a questionnaire survey. The questionnaire form was mailed to 160 councilors of the Society, the target questionees. A total of 94 answers (58% of the target questionees) sent back were used for analyses.

RESULTS

The analyses revealed that 75% of the hospitals charged most of the patients who receive radiotherapy in an outpatient setting a consultation fee. The introduction of the consultation fee led to some changes in radiation oncology clinics, as evidenced by the response of 'more careful observations by medical staff' in 37% of questionees and a 12% increase in the number of full-time radiation oncology nurses. It was also shown that the vast majority (92%) of radiation oncologists expected a positive influence of the consultation fee on radiation oncology clinics in Japan.

CONCLUSIONS

Our questionnaire survey revealed the present status of the use of a newly introduced consultation fee for outpatient radiotherapy, and the results suggested its possible effect on promoting a multidisciplinary medical care system in radiation oncology departments in Japan.

Novel parameter predicting grade 2 rectal bleeding after iodine-125 prostate brachytherapy combined with external beam radiation therapy

PURPOSE

To propose a novel parameter predicting rectal bleeding on the basis of generalized equivalent uniform doses (gEUD) after (125)I prostate brachytherapy combined with external beam radiation therapy and to assess the predictive value of this parameter.

METHODS AND MATERIALS

To account for differences among radiation treatment modalities and fractionation schedules, rectal dose-volume histograms (DVHs) of 369 patients with localized prostate cancer undergoing combined therapy retrieved from corresponding treatment planning systems were converted to equivalent dose-based DVHs. The gEUDs for the rectum were calculated from these converted DVHs. The total gEUD (gEUDsum) was determined by a summation of the brachytherapy and external-beam radiation therapy components.

RESULTS

Thirty-eight patients (10.3%) developed grade 2+ rectal bleeding. The grade 2+ rectal bleeding rate increased as the gEUDsum increased: 2.0% (2 of 102 patients) for <70 Gy, 10.3% (15 of 145 patients) for 70-80 Gy, 15.8% (12 of 76 patients) for 80-90 Gy, and 19.6% (9 of 46 patients) for >90 Gy (P=.002). Multivariate analysis identified age (P=.024) and gEUDsum (P=.000) as risk factors for grade 2+ rectal bleeding.

CONCLUSIONS

Our results demonstrate gEUD to be a potential predictive factor for grade 2+ late rectal bleeding after combined therapy for prostate cancer.

Symptomatic pericardial effusion after chemoradiation therapy in esophageal cancer patients

PURPOSE

We investigated clinical and treatment-related factors as predictors of symptomatic pericardial effusion in esophageal cancer patients after concurrent chemoradiation therapy.

METHODS AND MATERIALS

We reviewed 214 consecutive primary esophageal cancer patients treated with concurrent chemoradiation therapy between 2001 and 2010 in our institute. Pericardial effusion was detected on follow-up computed tomography. Symptomatic effusion was defined as effusion ≥grade 3 according to Common Terminology Criteria for Adverse Events v4.0 criteria. Percent volume irradiated with 5 to 65 Gy (V5-V65) and mean dose to the pericardium were evaluated employing dose-volume histograms. To evaluate dosimetry for patients treated with two-dimensional planning in the earlier period (2001-2005), computed tomography data at diagnosis were transferred to a treatment planning system to reconstruct three-dimensional plans without modification. Optimal dosimetric thresholds for symptomatic pericardial effusion were calculated by receiver operating characteristic curves. Associating clinical and treatment-related risk factors for symptomatic pericardial effusion were detected by univariate and multivariate analyses.

RESULTS

The median follow-up was 29 (range, 6-121) months for eligible 167 patients. Symptomatic pericardial effusion was observed in 14 (8.4%) patients. Dosimetric analyses revealed average values of V30 to V45 for the pericardium and mean pericardial doses were significantly higher in patients with symptomatic pericardial effusion than in those with asymptomatic pericardial effusion (P<.05). Pericardial V5 to V55 and mean pericardial doses were significantly higher in patients with symptomatic pericardial effusion than in those without pericardial effusion (P<.001). Mean pericardial doses of 36.5 Gy and V45 of 58% were selected as optimal cutoff values for predicting symptomatic pericardial effusion. Multivariate analysis identified mean pericardial dose as the strongest risk factor for symptomatic pericardial effusion.

CONCLUSIONS

Dose-volume thresholds for the pericardium facilitate predicting symptomatic pericardial effusion. Mean pericardial dose was selected based not only on the optimal dose-volume threshold but also on the most significant risk factor for symptomatic pericardial effusion.

Japanese nationwide multi-institutional cohort study of prostate cancer brachytherapy with permanent seed implantation

e16090

Background: Brachytherapy with permanent iodine-125 seed implantation (PI) has been approved in 2003 in Japan. Multi-institutional cohort study (Japanese Prostate Cancer Outcome Study of Permanent Seed Implantation; J-POPS, NCT00534196) assessing the treatment feature, efficacy, safety and health-related quality of life (QOL) has started in July 2005. Six thousand nine hundred and twenty-seven cases were enrolled to this study until December 2010 from 68 institutes around the country, which is approximately 40% of all the cases treated in Japan at that time. Methods: Patient’s background, cancer character, treatment feature such as combined therapy of external beam or hormone, post PI dosimetric information, treatment efficacy with PSA level, voiding symptoms with IPSS and treatment related adverse events according to NCI-CTCAE are investigated. PSA was measured every 3 months and symptoms accompanied to the treatment were assessed 3 to 6 months after the treatment. Backgrounds and treatment assessments of 2,341 patients enrolled in J-POPS during the initial 2 years are evaluated. Results: Patients’ age ranged from 45 to 89 (median 69) year-old and 99.0% of the cases were performance status 0 (ECOG criteria). Family history of prostate cancer was seen in 6.2%. PSA levels on cancer diagnosis were 1.60 to 42.0 (mean 6.80) ng/ml, clinical stage T2a or less was 89.9%, T2b was 5.2%, T2c was 2.9% and T3a-T3b was 0.8%. Gleason score (GS) less than 7 was 56.6%, GS 7 was 39.7%, and GS above 7 was 3.6%. According to NCCN risk classification, 44.2% was classified as low risk, 48.3% as intermediate risk and 5.7% as high risk. Androgen deprivation therapy (ADT) was performed in 48.5% of the patients and 23.4% was combined with external beam radiation therapy (EBRT). CT scan based first post therapeutic month dosimetry revealed that prostatic mean V100 and D90 for the cases treated with seed alone were 94.8% and 160.7 Gy, respectively. As for adequate control of radiation dose at rectum (mean R100 = 0.3 cc) and urethra (mean D5 = 223.4 Gy), high grade toxicities appeared very seldom. Conclusions: Outcomes of J-POPS will produce clinical evidence of PI that can be internationally accepted.

Comparison of preplanning and intraoperative planning for I-125 prostate brachytherapy

OBJECTIVE

To compare two widely used permanent prostate brachytherapy techniques, preplanning and intraoperative planning, based on postimplant dosimetry, toxicity and biochemical outcomes.

METHODS

Between 2003 and 2006, 665 men with localized prostate cancer were treated with permanent interstitial implantation. The first 227 consecutive men were treated with the preplanning technique, followed by 438 men treated with the intraoperative technique. Late toxicity was scored by the Common Terminology Criteria for Adverse Events v.4.0. Biochemical failure was defined as a prostate-specific antigen increase of more than 2 ng/ml above the nadir value excluding a benign bounce. Univariate and multivariate analyses were performed to identify the variables associated with biochemical failure-free survival.

RESULTS

Postimplant target coverage was similar in the two groups, with a small difference in risk organ doses. Mean V100 was 96.3 vs. 96.7% (P = 0.205), D90 was 119.6 vs. 119.4% (P = 0.884), urethral D10 was 157.5 vs. 146.1% (P = 0.010), rectal V100 was 0.57 vs. 0.43 cc (P = 0.002) in the preplanning and intraoperative planning groups, respectively. Acute and late Grade 3 genitourinary and gastrointestinal toxicities were <1% for both methods. The 5-year biochemical failure-free survival rate was 95.4% for the preplanning and 94.0% for the intraoperative planning group (P = 0.776). Multivariate analysis revealed Gleason score, biopsy positive rate and V100 to be predictors of biochemical failure-free survival, while the planning technique was not significant.

CONCLUSION

This large-scale analysis of high-quality implants revealed similar postimplant dosimetry, toxicity profiles and biochemical failure-free survival for the preplanning and intraoperative planning methods.

[Chemoradiotherapy for advanced gastric cancer]

In the US and Europe, chemoradiotherapy has become a standard treatment not only for head and neck cancer, esophageal cancer, pancreatic cancer, and rectal cancer, but also for gastric cancer. In particular, chemoradiotherapy has been established as an adjuvant therapy. In Japan, it has not been established as a standard treatment. Its indications are limited, and it is often performed as palliative care. Disadvantages of radiation therapy for gastric cancer include the difficulty of establishing the area to irradiate due to peristaltic movement, risk of perforation and ulceration from high-dose radiation, and ineffectiveness against adenocarcinoma with low radiosensitivity. In recent years, technological advancement of radiation therapy has enabled pinpoint accuracy in the treatment of primary gastric lesions and regional lymph nodes. There has been much anticipation that chemoradiotherapy will become a part of multidisciplinary treatment for advanced cancer. This report describes the current state of chemoradiotherapy for gastric cancer in Japan and overseas, and outlines our approach to locally advanced gastric cancer.