Results Of Proton Beam Therapy Research Articles

Clinical Outcomes of Proton Beam Therapy for Unresectable Locally Advanced Pancreatic Cancer: A Single-Center Retrospective Study

PurposeWe retrospectively researched the treatment outcome of proton beam therapy (PBT) and assessed its efficacy for inoperable locally advanced pancreatic cancer (LAPC) at our institution. Materials and MethodsFifty-four patients (28 males and 26 females, median age 67 years of ranges from 40 to 88 years were diagnosed with unresectable stage III LAPC and administered PBT from April 2009 to March 2020. Either patients who could not complete PBT, or had new distant metastases during the treatment, or did not have enough follow-up time were excluded from this study. All patients were clinically staged based on the International Union of Cancer TNM staging system (UICC 8th edition) using CT, MRI, and PET, and were diagnosed as stage III (histologic type: eighteen adenocarcinoma patients, thirty-six clinically diagnosed patients). PBT was performed using the passive method, with a median total dose of 67.5 GyE (range: 50-77 GyE/25-35 fractions). Chemotherapy was used in combination during PBT in forty-six patients (85.2%). Overall survival (OS), local progression-free survival (LPFS), progression-free survival (PFS), and median overall survival time (MST) were analyzed by Kaplan-Meier and log-rank tests. Univariate and multivariate analyses were performed for the following factors: maximum standardized uptake value (SUVmax), ECOG-performance status (PS), tumor site, total irradiation dose, concurrent chemotherapy, and primary tumor site. Cutoff values for SUVmax and tumor diameter were estimated using receiver operating characteristic (ROC) curves and area under the curve (AUC) based on OS. Multivariate analysis was evaluated using the Cox proportional hazards models. Adverse events were evaluated using CTCAE ver. 5.0. ResultsThe median observation period was 17.4 months of ranges from 4.0 to 89.7 months. The median tumor diameter was 36.5 mm of ranges from 15 to 90 mm, the median SUVmax was 5.85 (range: 2.1-27.6), and their cutoff values were estimated to 37 mm and 4.8 mm, respectively. 1-, 2-year OS were 77.8%, 35.2% with MST 18.2 months, respectively and only one patient survived more than 5 years. 12 patients (22.2%) developed local recurrence, and 1-, 2-year LPFS rate were 89.7% and 74.5%, respectively; PFS at 1-year was 58.8%. PS score, Tumor site and irradiation dose were the prognostic factor related to OS that showed a significant difference. On the other hand, there was a significant difference in factors involved in LPFS, 96.7%/77.9% in the first year and 86.6%/54.4% in the second year in the groups with tumor dose ≥67.5 GyE and <67.5 GyE, respectively (p = 0.015). Treatment-related acute toxicities were neutropenia (Grade1/2/3:3.7%/11.1%/31.5%), leukopenia (Grade 1/2/3:1.8%/7.4%/20.4%), and thrombocytopenia (Grade 1/2:1.8%/7.4%), while the late effects including peptic ulcer were captured only grade2+. The late adverse events of Grade 3 or higher were not observed. ConclusionsPBT achieving 67.5 Gy combined with standard chemotherapy showed the excellent local control for unresectable LAPC. Total irradiation dose, Tumor site and PS score at an initial diagnosis could be important prognostic factors. In this study, the dose-effect relationship was found so an increase in dose should be considered to improve prognosis.

A meta-analysis comparing efficacy and safety between proton beam therapy versus carbon ion radiotherapy.

This study aimed to compare the outcomes of proton beam therapy (PBT) and carbon ion radiotherapy (CIRT) by a systematic review and meta-analysis of the existing clinical evidence. A systematic literature search was performed to identify studies comparing the clinical outcomes of PBT and CIRT. The included studies were required to report oncological outcomes (local control [LC], progression-free survival [PFS], or overall survival [OS]) or adverse events. Eighteen articles comprising 1857 patients (947 treated with PBT and 910 treated with CIRT) were included in the analysis. The pooled analysis conducted for the overall population yielded average hazard ratios of 0.690 (95% confidence interval (CI), 0.493-0.967, p = 0.031) for LC, 0.952 (95% CI, 0.604-1.500, p = 0.590) for PFS, and 1.183 (0.872-1.607, p = 0.281) for OS with reference to CIRT. The subgroup analyses included patients treated in the head and neck, areas other than the head and neck, and patients with chordomas and chondrosarcomas. These analyses revealed no significant differences in most outcomes, except for LC in the subgroup of patients treated in areas other than the head and neck. Adverse event rates were comparable in both groups, with an odds ratio (OR) of 1.097 (95% CI, 0.744-1.616, p = 0.641). Meta-regression analysis for possible heterogeneity did not demonstrate a significant association between treatment outcomes and the ratio of biologically effective doses between modalities. This study highlighted the comparability of PBT and CIRT in terms of oncological outcomes and adverse events.

Treatment Outcomes of Proton Beam Therapy for Esophageal Squamous Cell Carcinoma at a Single Institute

Recently, proton beam therapy (PBT) has gathered attention for improving outcomes and reducing toxicities in various cancers; however, the evidence for esophageal squamous cell carcinoma (ESCC) is lacking. Our study retrospectively evaluated the outcomes of PBT for ESCC patients at a single institute. The patients treated with PBT between November 2015 and February 2022 were included in the study, excluding those with distant metastases or those that had undertaken prior treatment for esophageal cancer (EC). The 3 year overall survival (OS) and progression-free survival (PFS) rates were calculated based on stage grouping. The patterns of failure, salvage treatment outcomes, and toxicity profiles were analyzed. The median follow-up was 35.1 months, and 132 patients were analyzed. The 3 year OS and PFS rates for the stages I, II, and III disease cases were 81.0%, 62.9%, and 51.3%; and 70.6%, 71.8%, and 39.8%, respectively. Nineteen patients presented isolated local progression, ten patients underwent appropriate salvage procedures, and nine were successfully salvaged. One patient with isolated regional progression was also salvaged. No cases of grade ≥ 4 lymphopenia were observed. One patient had grade 4 pericardial effusion and esophageal fistula. For the patients with ESCC, PBT is an effective treatment in terms of the survival outcomes and toxicities.

PO-1532 Long-term outcomes of proton beam therapy for elderly patients with prostate cancer

PO-1532 Long-term outcomes of proton beam therapy for elderly patients with prostate cancer

Proton beam therapy for gliomas: a multicenter prospective registry study from all proton beam facilities in Japan

Abstract We reviewed the outcomes of glioma patients enrolled in a prospective observational registry study of proton beam therapy (PBT) in Japan. The inclusion criteria were glioma patients registered in the Electronic Data Capture system, the Proton-net, between May 2016 and July 2019. Data on patient characteristics, treatments, late adverse events, survival status, recurrence and secondary tumors were extracted and statistically analyzed. The primary endpoint was the overall survival (OS) rate, and the secondary endpoints were the progression-free survival (PFS) rate and cumulative local recurrence rate (cLRR). Of the 65 primary brain tumor patients registered, 29 glioma patients from eight of 19 PBT facilities met the inclusion criteria. There were 19 glioblastoma patients, eight of other malignant gliomas, and two of low-grade gliomas. For glioblastomas, with a median follow-up period of 16 months, the median survival time was 21.2 months and the OS at 1, 2, 3 and 4 years were 77.4%, 44.9%, 23.9% and 23.9%, respectively. The median PFS period was 10.1 months, the 1, 2, 3 and 4-year PFS were 32.4%, 19.4%, 9.7% and 9.7%, respectively. The 1, 2, 3 and 4-year cLRR were 56.1%, 68.8%, 78.4 and 78.4%, respectively. Grade 3 brain necrosis was observed in two patients. No secondary tumor was observed. This is the first report on the current status of PBT for gliomas in Japan. For glioblastomas, the outcomes of PBT are estimated to be equivalent to historical data of photon therapy. The results of a prospective comparative evaluation of PBT and photon therapy are awaited.

Outcomes of Proton Beam Therapy Compared With Intensity-Modulated Radiation Therapy for Uterine Cancer.

To compare Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) in patients with endometrial cancer receiving adjuvant pelvic radiation therapy with proton beam therapy (PT) versus intensity-modulated radiation therapy (IMRT). Patients with uterine cancer treated with curative intent who received either adjuvant PT or IMRT between 2014 and 2020 were identified. Patients were enrolled into a prospective registry using a gynecologic-specific subset of PRO-CTCAE designed to assess symptom impact on daily living. Questions included gastrointestinal (GI) symptoms of diarrhea, flatulence, bowel incontinence, and constipation in addition to other pertinent gynecologic, urinary, and other general symptoms. Symptom-based questions were on a 0- to 4-point scale, with grade 3+ symptoms occurring frequently or almost always. Patient-reported toxicity was analyzed at baseline, end of treatment (EOT), and at 3, 6, 9, and 12 months after treatment. Unequal variance t tests were used to determine if treatment type was a significant factor in baseline-adjusted PRO-CTCAE. Sixty-seven patients met inclusion criteria. Twenty-two received PT and 45 patients received IMRT. Brachytherapy boost was delivered in 73% of patients. Median external beam dose was 45 Gy for both PT and IMRT (range, 45-58.8 Gy). When comparing PRO-CTCAE, PT was associated with less diarrhea at EOT (P = .01) and at 12 months (P = .24) than IMRT. Loss of bowel control at 12 months was more common in patients receiving IMRT (P = .15). Any patient reporting grade 3+ GI toxicity was noted more frequently with IMRT (31% versus 9%, P = .09). Adjuvant PT is a promising treatment for patients with uterine cancer and may reduce patient-reported GI toxicity as compared with IMRT.

Retrospective Clinical Outcomes of Proton Beam Therapy for Unresectable Locally Advanced Pancreatic Cancer

<h3>Purpose/Objective(s)</h3> We retrospectively researched on the treatment outcomes and assessed the efficacy of proton beam therapy (PBT) for unresectable locally advanced pancreatic cancer (LAPC). <h3>Materials/Methods</h3> Fifty-four patients who were diagnosed unresectable LAPC and administered PBT between April 2009 to March 2020 at our institution. Patients who could not completed PBT, had new distant metastases during treatment, and did not have enough follow-up time were excluded in this study. Statistical analyses were performed by calculating overall survival rate (OS) and local control rate (LC). Median survival time (MST) was analyzed by several following factors; maximum standardized uptake values (SUV_max) of FDG-PET evaluation, performance status (PS), tumor site, total irradiation dose, and combination use of chemotherapy. Treatment toxicities were evaluated by Common Terminology Criteria for Adverse Events (CTCAE ver.5.0). OS, MST, and LC were analyzed using the Kaplan-Meier method and log-rank test. The cut-off values for SUV_max and tumor diameter were estimated using the receiver operating characteristic (ROC) curve and area under the curve (AUC) based on MST. <h3>Results</h3> This study included 28 men and 26 women whose median age was 67.5 years (range, 40 to 88 years). All patients were clinical stage III LAPC according to the Union for International Cancer Control (UICC) TNM staging system (8th edition). Median follow-up time was 17.4 months (range, 4.0 to 89.7 months). The median total dose was 67.5GyE (range, 50-77 GyE/25-35 fractions). The median tumor diameter was 36.5mm (range, 15 to 90 mm). The median SUV_max was 5.85 (range, 2.1 to 27.6). Chemotherapy regimens during PBT were following; 24 patients were gemcitabine alone, 5 were tegafur-gimeracil-oteracil (TS-1) alone, 17 were paclitaxel and TS-1. Eight patients did not receive chemotherapy because of their poor general condition. The One-year, 2-year, 3-year OS were 74.1%, 33.3%, 10.8%, respectively. The One-year, 2-year, 3-year LC were 89.0%, 84.6%, 84.6%, respectively. The MST was 17.1 months. Only one patient survived longer than 5 years. The cut-off values were estimated for SUV_max: 4.8 and tumor diameter: 37mm. Two-year OS based on PS-score group were following; PS 0/1/2: 26.1/ 13.4/8.0 months, respectively with significant differences (each group P<0.01). Treatment related acute toxicities were neutropenia (Grade1/2/3: 2/6/17 patients), leukopenia (Grade1/2/3: 1/4/11 patients), thrombocytopenia (Grade1/2: 1/4 patients), respectively. Late toxicity was gastrointestinal ulcer (Grade1/2: 2/2 patients). No Grade 3 or higher late adverse events were observed. <h3>Conclusion</h3> PBT combined standard chemotherapy achieved excellent local control. However, it did not control systematic tumor progression. PS score at first visit could be important prognostic factor.

Retrospective Analysis of Proton Beam Therapy for Postoperative Locally Recurrent Rectal Cancer

<h3>Purpose/Objective(s)</h3> The outcomes of postoperative locally recurrent rectal cancer (PLRRC) are unsatisfactory in the multimodal treatment era. We retrospectively analyzed the outcomes of proton beam therapy (PBT) for PLRRC at our institution. <h3>Materials/Methods</h3> We included 79 PBT-treated PLRRC patients between December 2008 to December 2019. We excluded patients with prior history of salvage surgery, radiotherapy, or distant metastasis before PBT, and those treated with postoperative adjuvant PBT. We included patients who had history of chemotherapy. We estimated the overall survival (OS), disease-free survival (DFS), and local control (LC) using the Kaplan–Meier method. The prognostic factor for each outcome was verified using a Cox proportional hazards model. <h3>Results</h3> We enrolled 23 patients. The median follow-up time was 36.8 months. The median age was 64 (range, 34–83) years. The median time from surgery to recurrence was 18.1 months. Twenty patients (87%) had adenocarcinoma, two had carcinoid, and one had neuroendocrine carcinoma. The postoperative recurrent sites were presacral (12 patients), pelvic side wall (seven patients), and anastomoses (four patients). The median recurrent tumor size was 37 (range, 16–130) mm. The median maximum standardized uptake value (SUV_max) of Fluorine-18-fluorodeoxyglucose-positron emission tomography/computed tomography (18^F-FDG-PET/CT) before PBT was 7.4. Twenty-one patients (91%) received PBT alone. The median total dose was 72.6 (range, 60–87) Gy relative biological effectiveness. The treatment response was stratified by initial imaging (median, two months) after PBT. Of 23 patients, 16 (70%) received 18^F-FDG-PET/CT for initial imaging modality. Eleven patients had complete response (CR), eight had partial response, two had stable disease, and two had progressive disease. Eleven patients (48%) had lumbar or anal pain before PBT and had symptomatic pain improvement after PBT. Three- and five-year OS, DFS, and LC were 71.5%/43.3%, 37.3%/37.3%, and 54.5%/46.7%, respectively. The SUV_max of 18^F-FDG-PET/CT before PBT (cut-off value:10) showed significant difference for OS (<i>P</i>=0.0135), DFS (<i>P</i>=0.047), and LC (<i>P</i>=0.0239). The patients who achieved CR after PBT had significantly better LC compared with those with non-CR (HR 4.71, 95% CI 1.18–18.65, <i>P</i>=0.0177). Elderly patients (≧65 years) had significantly better LC and DFS. The patients with pain before PBT and larger tumor (≧30 mm) also had significantly lower DFS. Of 23 patients, 12 (52%) had further local recurrence after PBT. One patient developed grade 2 acute radiation dermatitis. Grade 4 late gastrointestinal toxicity (perforation) was recorded in three patients, two of which were associated with reirradiation for further local recurrence after PBT. <h3>Conclusion</h3> The outcomes of PBT for PLRRC are better than those of conventional photon therapy, and are comparable with those of surgery. 18^F-FDG-PET/CT before/after PBT correctly reflected the treatment effect and prognosis.

Treatment outcomes of proton beam therapy combined with retrograde intra-arterial infusion chemotherapy for locally advanced oral cancer in the elderly

The aim of this study was to evaluate the therapeutic efficacy and safety of proton beam therapy combined with retrograde intra-arterial infusion chemotherapy in elderly patients with locally advanced oral cancer. Between February 2009 and October 2019, 42 oral cancer patients aged ≥75 years were treated with this therapy. Median age was 80 years (range 75–90 years) and the median follow-up duration was 39 months (range 2–106 months). Of the 42 patients, 34 (81%) were diagnosed with stage IV cancer. The 3-year overall survival, local control, progression-free survival, and disease-specific survival rates were 56%, 69%, 32%, and 67%, respectively. Regarding acute toxicities, grade 3 neutropenia was observed in six patients (14%), anaemia in five (12%), acute kidney injury in one (2%), and oral mucositis in 18 (42%). Late toxicities of grade 3 were observed in seven patients: dysphagia in six (14%) and osteonecrosis of the jaw in one (2%). This study showed that proton beam therapy combined with retrograde intra-arterial infusion chemotherapy was effective for elderly patients with oral cancer, and toxicities were tolerable and manageable. The study findings suggest that this therapy is a potential treatment option for elderly oral cancer patients with difficulty in surgery and systemic chemotherapy.

Hypofractionated Proton Beam Therapy for cT1-2N0M0 Non-small Cell Lung Cancer Patients With Interstitial Lung Disease.

To evaluate the outcomes of proton beam therapy (PBT) for early-stage non-small cell lung cancer (NSCLC) in patients with interstitial lung disease (ILD). Between 2002 and 2017, 110 patients receiving hypofractionated PBT for cT1-2N0M0 NSCLC were reviewed. Of the 110 patients, 17 were diagnosed with ILD. The median follow-up period was 37.8 months. No significant difference in the 1-year cumulative rate of grade ≥2 pneumonitis was observed between patients with and those without ILD (17.6% vs. 14.1%, p=0.708). The lung doses were significantly lower in patients with than in those without ILD among patients without grade ≥2 pneumonitis. There were no significant differences in overall survival or local recurrence-free rates according to the presence of ILD. PBT appears to be a feasible and effective treatment for cT1-2N0M0 NSCLC in patients with ILD, but the lung dose should be strictly reduced.

Long-term Clinical Outcomes in Favorable Risk Prostate Cancer Patients Receiving Proton Beam Therapy.

PurposeLong-term data regarding the disease control outcomes of proton beam therapy (PBT) for patients with favorable risk intact prostate cancer (PC) are limited. Herein, we report our institution's long-term disease control outcomes in PC patients with clinically localized disease who received PBT as primary treatment.MethodsOne hundred sixty-six favorable risk PC patients who received definitive PBT to the prostate gland at our institution from 2010 to 2012 were retrospectively assessed. The outcomes studied were biochemical failure-free survival (BFFS), biochemical failure, local failure, regional failure, distant failure, PC-specific survival, and overall survival. Patterns of failure were also analyzed. Multivariate Cox proportional hazards modeling was used to estimate independent predictors of BFFS.ResultsThe median length of follow-up was 8.3 years (range, 1.2–10.5 years). The majority of patients had low-risk disease (58%, n = 96), with a median age of 64 years at the onset of treatment. Of 166 treated men, 13 (7.8%), 8 (4.8%), 2 (1.2%) patient(s) experienced biochemical failure, local failure, regional failure, respectively. Regional failure was seen in an obturator lymph node in 1 patient and the external iliac lymph nodes in the other. None of the patients experienced distant failure. There were 5 (3.0%) deaths, none of which were due to PC. The 5- and 8-year BFFS rate were 97% and 92%, respectively. None of the clinical disease characteristics or treatment-related factors assessed were associated with BFFS on multivariate Cox proportional hazards modeling (all P > .05).ConclusionDisease control rates reported in our assessment of PBT were similar to those reported in previous clinically localized intact PC analyses, which used intensity-modulated radiotherapy, three-dimensional conformal radiotherapy, or radical prostatectomy as definitive therapy. In addition, BFFS rates were similar, if not improved, to previous PBT studies.

Multi-Institutional Retrospective Analysis of the Outcomes of Proton Beam Therapy for Patients With 1 to 3 Pulmonary Oligometastases From Various Primary Cancers

PurposeOur purpose was to evaluate the efficacy of proton beam therapy (PBT) in patients with 1 to 3 pulmonary oligometastases from various primary cancers in Japan. Methods and MaterialsThis multi-institutional retrospective survey included 118 patients with 141 metastatic lung tumors from miscellaneous primary cancers, across 6 Japanese institutions, and involved the analyses of local progression-free rate (LPF), distant progression-free rate, progression-free survival rate, cause-specific survival rate, and overall survival rate (OS). Treatment-induced adverse effects of grade ≥2 were evaluated according to the Common Terminology Criteria for Adverse Events (version 4.0). Cox proportional hazards regression models were used in univariable analysis and multivariable analysis (MVA) for the identification of the prognostic factors of LPF and OS. ResultsThe median follow-up duration from the time of PBT was 25.5 months. The major primary disease sites included colorectal cancer (42.4%), lung cancer (11.9%), head and neck cancer (8.5%), and kidney cancer (8.5%). For years 1, 2, and 3, LPFs were 92.2%, 86.3%, and 78.4%; distant progression-free rates were 59.1%, 44.1%, and 34.0%; progression-free survival rates were 49.6%, 31.7%, and 24.2%; cause-specific survival rates were 83.4%, 72.5%, and 64.8%; and OS rates were 79.0%, 67.8%, and 59.6%, respectively. Eight patients developed acute adverse effects (grade ≥2). Ten patients developed radiation pneumonitis (grade 2) as a late adverse effect. None of the patients developed severe late toxicity (grade ≥3). Colorectal cancer as the primary disease was the only prognostic factor associated with LPF that remained independently significant in the MVAs performed using 3 sets of parameters (hazard ratio [HR], 3.31-4.76 in 3 MVA sets). In the MVA, the significant prognostic factors for OS were performance status (HR, 2.78; 95% confidence interval, 1.01-7.67) and total tumor volume (HR, 1.01; 95% confidence interval, 1.00-1.02). ConclusionsPBT provides promising outcomes for pulmonary oligometastasis with acceptable toxicities.

Visual outcomes of proton beam therapy for choroidal melanoma at a single institute in the Republic of Korea.

We evaluate the ocular effects of proton beam therapy (PBT) in a single institution, in Korea, and identify factors contributing to decreasing visual acuity (VA) after PBT. A total of 40 patients who received PBT for choroidal melanoma (2009‒2016) were reviewed. Dose fractionation was 60‒70 cobalt gray equivalents (CGEs) over five fractions. Complete ophthalmic examinations including funduscopy and ultrasonography were performed at baseline and at 3, 6, and 12 months after PBT, then annually thereafter. Only patients with at least 12 months follow-up were included. During the follow-up, consecutive best-corrected visual acuity (BCVA) changes were determined, and univariate and multivariate logistic regression analyses were performed to identify predictors for VA loss. The median follow-up duration was 32 months (range: 12‒82 months). The final BCVA of nine patients was > 20/40. The main cause of vision loss was intraocular bleeding, such as neovascular glaucoma or retinal hemorrhage. Vision loss was correlated with the tumor size, tumor distance to the optic disc or fovea, maculae receiving 30 CGEs, optic discs receiving 30 CGEs, and retinas receiving 30 CGEs. Approximately one-third of PBT-treated choroidal melanoma patients with good pretreatment BCVA maintained their VA. The patients who finally lost vision (VA < count fingers) usually experienced rapid declines in VA from 6‒12 months after PBT. Tumor size, tumor distance to the optic disc or fovea, volume of the macula, and optic discs or retinas receiving 30 CGEs affected the final VA.

Clinical Outcomes of Proton Beam Therapy for Stage I Lung Cancer in Patients with Interstitial Pneumonia: A Multi-Institutional Retrospective Study in Japan

Stereotactic body radiotherapy (SBRT) is a standard option for medically inoperable stage I non-small cell lung cancer (NSCLC). However, interstitial pneumonia (IP) is considered to be a relative contraindication for SBRT. The rates of Grade ≥3 pneumonitis after SBRT in patients with IP have been reported to range from 10% to 38%. Proton beam therapy (PBT) might have an advantage in treating patients with IP. The purpose of this study is to clarify the safety and the effectiveness of PBT for Stage I NSCLC in patients with IP. Six hundred sixty-nine patients with histologically or clinically diagnosed Stage I NSCLC according to the 7th edition of UICC received passive-scattering PBT from April 2004 and December 2013 at 8 institutions in Japan. Of them, 51 patients with comorbidity of IP, which was diagnosed by CT findings, were identified and retrospectively analyzed survivals, local control, and adverse events. Forty-six (90.2%) of 51 patients were male, with a median age of 75 years (range, 60–89 years). Ten (19.6%) patients required corticosteroids or immunosuppressants, and 4 (7.8%) patients received long-term oxygen therapy. NSCLC was histologically confirmed in 32 (62.7%) patients. Clinical T stages included T1a (n = 19; 37.2%), T1b (n = 14; 27.4%), and T2a (n = 18; 35.3%). The total irradiation doses of PBT ranged from 89.3 to 131.3 Gy (RBE) BED10 (median, 109.6 Gy (RBE)). The median follow-up period was 25.1 months (range, 3.1-65.9 months) for all patients. The 2-year overall survival, disease specific survival, progression-free survival, and local progression-free rates for all patients were 71.6% (95% confidence interval [CI]: 56.9–82.8%), 83.9% (95% CI: 69.7–92.1%), 52.2% (95% CI: 38.2–65.9%), and 82.0% (95% CI: 66.5–91.2%), respectively. The incidence of Grade 2, 3, 4, and 5 pneumonitis including exacerbation of IP was 13.7%, 0%, 0%, and 3.9%, respectively. The incidence of Grade 3 dermatitis was 2.0%. No Grade 4 or severe adverse events, other than pneumonitis, were observed. PBT for Stage I NSCLC in patients with IP seems to be tolerable and effective.

Outcomes of Proton Beam Therapy for Lung Cancer in Patients with Interstitial Pneumonia

Outcomes of Proton Beam Therapy for Lung Cancer in Patients with Interstitial Pneumonia

Clinical Outcomes of Proton Beam Therapy for Ground-Glass Opacity-Type Lung Cancer.

PurposeSurgery is the standard treatment for early-stage non-small cell lung cancer (NSCLC), including ground-glass opacity (GGO)-type lung cancer. However, some patients are inoperable or refuse to undergo surgery. To explore whether proton beam therapy (PBT) can be an alternative to surgical resection in these patients, this study aimed to examine the retrospective treatment outcomes of patients with GGO-type lung cancer who underwent PBT.Patients and MethodsPatients with stage I NSCLC and GGOs who underwent PBT at the Medipolis Proton Therapy and Research Center (Kagoshima, Japan) between April 2011 and September 2015 were included. Patients were treated with a total dose of 66 GyE delivered in 10 fractions. Survival curves were calculated using the Kaplan–Meier method, and treatment-related adverse events (AEs) were assessed.ResultsA total of 48 patients (median age: 70.9 ± 9.2 years; men: 54.2%) were analyzed, among whom 53 tumors were observed. The 3-year overall survival rate after PBT was 91.7% (95% confidence interval [CI], 79.3–96.8%), the 3-year disease-free survival rate was 85.4% (95% CI: 71.8–92.8%), and the 3-year local control rate among 53 tumors was 92.5% (95% CI: 81.1–97.1%). During the 3-year follow-up period, 4 patients died, and 3 survived despite recurrence or metastasis. Common AEs were radiation pneumonitis (89.6%), rib fracture (27.1%), and cough (27.1%). None of the patients developed grade ≥3 treatment-related AEs.ConclusionThe results of this study suggest that PBT may be a promising alternative for patients with GGO-type lung cancer when surgical resection is not feasible, with excellent survival outcomes and tolerable treatment-related AEs.

Proton beam therapy is a safe and effective treatment in elderly patients with esophageal squamous cell carcinoma.

BackgroundThere are many elderly patients with esophageal squamous cell carcinoma (ESCC). However, there are currently few articles regarding the clinical outcome following proton beam therapy in these patients. The purpose of this study was to evaluate the clinical results of proton beam therapy in elderly patients with ESCC.MethodsBetween January 2009 and December 2013, patients aged ≥75 years who underwent proton beam therapy were examined using multi‐institutional data from Japan.ResultsThere were 38 inoperable patients (70.4%) and 16 operable patients (29.6%). More than 40% of patients had stage III/IV ESCC. The five‐year overall and cancer‐specific survival rates were 56.2% and 71.7%, respectively. Performance status was the only factor that significantly influenced overall survival during the multivariate analysis. The five‐year local control rate was 61.8%, and local recurrence occurred within 13 months in 82.4% of patients,. There was no grade 3 or higher toxicity, excluding three patients with grade 3 esophageal ulcers.ConclusionsIn conclusion, proton beam therapy may become an alternative treatment with lower toxicity in elderly patients with ESCC, compared to surgery or conventional X‐ray radiotherapy. This includes inoperable patients.Key pointsSignificant findings of the studyProton beam therapy was a safe and effective treatment for elderly patients with esophageal squamous cell carcinoma (ESCC) including inoperable patients.What this study addsProton beam therapy may be a safer treatment choice for elderly patients with ESCC compared to conventional X‐ray radiotherapy.

Therapeutic results of proton beam therapy with concurrent chemotherapy for cT1 esophageal cancer and salvage endoscopic therapy for local recurrence.

Proton beam therapy (PBT) with concurrent chemotherapy is promising for esophageal squamous cell carcinoma (ESCC). The aim of study was to evaluate the outcome of concurrent chemo-proton therapy (CCPT), i.e., PBT with concurrent chemotherapy for cT1 ESCC and the salvage endoscopic therapy for local recurrence. Patients with clinical T1 ESCC who underwent CCPT (60 GyE) between April 2013 and April 2017 at the National Cancer Center Hospital East were investigated. The efficacy of CCPT at the primary site was evaluated via endoscopy; primary complete response (CR) was defined as disappearance of the tumor lesion/ulcer and absence of cancer cells on biopsy. Endoscopic evaluation was performed with the same protocol of conventional chemoradiotherapy. Local recurrence after CCPT was treated with endoscopic resection for cT1a and with esophagectomy or photodynamic therapy for cT1b+. Of the 44 patients (median age, 70years) that underwent CCPT, 43 patients (98%) achieved primary CR. Among the 44 patients, the 3-year overall survival rate was 95.2%. Five patients (11%) developed local recurrence without regional lymph node or distant metastasis and received endoscopic resection or photodynamic therapy. All five patients were alive with no recurrence after a median 23months. The results suggest that CCPT is an effective treatment for cT1 ESCC and careful endoscopic follow-up allows preferable local control with salvage endoscopic treatment.

Clinical Results of Proton Beam Therapy for Esophageal Cancer: Multicenter Retrospective Study in Japan.

There are few reports about the clinical results of proton beam therapy for esophageal cancer in a large population. The purpose of this study was to evaluate the clinical results of proton beam therapy for esophageal cancer in a large population using a multicentered database. Between January 2009 and December 2013, patients newly diagnosed with esophageal cancer and who had received proton beam therapy were retrospectively recruited from a database of four proton beam therapy centers in Japan. Two hundred and two patients (including 90 inoperable patients) fulfilled the inclusion criteria, and 100 patients (49.5%) had stage III/IV cancer (Union for International Cancer Control 8th). The 3-year and 5-year overall survival rate was 66.7% and 56.3%, respectively. The five-year local control rate was 64.4%. There were two patients with grade three pericardial effusion (1%) and a patient with grade three pneumonia (0.5%). No grade 4 or higher cardiopulmonary toxicities were observed (Common Terminology Criteria for Adverse Events version 4.0). This study suggests that proton beam therapy for esophageal cancer was not inferior in efficacy and had lower rates of toxicities in comparison to photon radiotherapy. Therefore, proton beam therapy can serve as an alternate treatment for patients with esophageal cancer.

EP-1444 Clinical results of proton beam therapy for unresectable intrahepatic cholangiocarcinoma

EP-1444 Clinical results of proton beam therapy for unresectable intrahepatic cholangiocarcinoma