Efficacy Of Carbon Ion Radiotherapy Research Articles

The role of apoptosis, immunogenic cell death, and macrophage polarization in carbon ion radiotherapy for keloids: Targeting the TGF-β1/SMADs signaling pathway

Keloids, characterized by excessive extracellular matrix (ECM) deposition and aberrant fibrous tissue proliferation, present significant therapeutic challenges due to their recalcitrant and recurrent nature. This study explores the efficacy of Carbon Ion Radiotherapy (CIRT) as a novel therapeutic approach for keloids, focusing on its impact on fibroblast proliferation, apoptosis induction, immunogenic cell death (ICD), macrophage polarization, and the TGF-β/SMAD signaling pathway. Utilizing a murine model of keloid formed by subcutaneous injection of zeocin in C57BL/6 mice, we demonstrated that CIRT effectively reduces collagenous fiber synthesis and collagen production in keloid tissues. Further, CIRT was shown to inhibit keloid fibroblast proliferation and to induce apoptosis, as evidenced by increased expression of apoptosis-related proteins and confirmed through flow cytometry and TUNEL assay. Notably, CIRT induced mitochondrial stress, leading to enhanced immunogenicity of cell death, characterized by increased expression of ICD markers and secretion of interferon-γ. Additionally, CIRT promoted a shift from M2 to M1 macrophage polarization, potentially reducing TGF-β release and mitigating ECM deposition. Our findings suggest that CIRT mediates its therapeutic effects through the inhibition of the TGF-β/SMAD signaling pathway, thereby attenuating ECM formation and offering a promising avenue for keloid treatment. This study underscores the potential of CIRT as an innovative strategy for managing keloids, highlighting its multifaceted impact on key cellular processes involved in keloid pathogenesis.

Carbon-ion radiotherapy for hepatocellular carcinoma with major vascular invasion: a retrospective cohort study

BackgroundMacroscopic vascular invasion (MVI) significantly impacts survival in patients with hepatocellular carcinoma (HCC), warranting systemic therapy over locoregional therapy. Despite novel approaches, HCC with MVI has a poor prognosis compared to early-to intermediate-stage HCC. This study aimed to evaluate the safety and efficacy of carbon-ion radiotherapy (C-ion RT) for HCC characterized by MVI.MethodsThis retrospective cohort study evaluated HCC patients with MVI treated using C-ion RT with a dose of 45.0–48.0 Gy/2 fractions or 52.8–60.0 Gy/4 fractions between 1995 and 2020 at our institution in Japan. We analyzed the prognostic factors and rates of local recurrence, survival, and adverse events. The local recurrence rate was determined using the cumulative incidence function, with death as a competing event. Survival rates were determined using the Kaplan–Meier method. The log-rank test for univariate analysis and the Cox proportional hazards model for multivariate analysis were used to compare subgroups.ResultsIn total, 76 patients with a median age of 71 years (range, 45–86 years) were evaluated. Among them, 68 had Child–Pugh grade A while eight had grade B disease. In 17 patients, the vascular tumor thrombus reached the inferior vena cava or main trunk of the portal vein. Over a median follow-up period of 27.9 months (range, 1.5–180.4 months), the 2-year overall survival, progression-free survival, and local recurrence rates were 70.0% (95% confidence interval [CI]: 57.7–79.4%), 32.7% (95% CI: 22.0–43.8%), and 8.9% (95% CI: 1.7–23.5%), respectively. A naïve tumor and a single lesion were significant prognostic factors for overall survival in the univariate analysis. Albumin-bilirubin grade 1 and a single lesion were independent prognostic factors in the multivariate analysis. Overall, four patients (5%) experienced grade 3 late adverse events, with no observed grade 4 or 5 acute or late adverse events.ConclusionsC-ion RT for HCC with MVI showed favorable local control and survival benefits with minimal toxicity.

Clinical Outcomes of Carbon-Ion Radiotherapy for Large-Sized (≥4cm) Hepatocellular Carcinoma

Radical treatment options for bulky unresectable locally advanced hepatocellular carcinoma (HCC) are limited. The purpose of this study is to evaluate the safety and efficacy of carbon-ion radiotherapy (C-ion RT) for bulky (≥4cm) locally advanced HCC. We performed a retrospective cohort study of patients with bulky (≥4cm) locally advanced HCC treated by C-ion RT between April 2000 and March 2020 in our institution. The eligibility criteria for this study were: (1) the treatment protocols of 45.0-48.0 Gy/2 fractions or 52.8-60.0 Gy/4 fractions, which proven the safety and efficacy in the past clinical trials; (2) Tumors within 3 intrahepatic lesions and with a maximum tumor diameter of 4 cm or greater; (3) N0M0 status; (4) an Eastern Cooperative Oncology Group performance status of 0 to 2; (5) controllable ascites; (6) Child-Pugh grade was A or B. Overall survival (OS), progression-free survival (PFS), and local control rate (LC) were calculated by the Kaplan-Meier method, and Cox regression analysis was used for multivariate analysis. Adverse events were evaluated by CTCAE ver. 5.0. JMP® 12 (SAS Institute Inc., Cary, NC, USA) was used for all analyses. We defined p < 0.05 as statistically significant. A total of 187 patients met the criteria and were evaluated. The median patient age was 73 years (range, 37-90), and 139 of 187 patients were male. Child-Pugh grade was A in 163 patients and B in 24. Modified albumin-bilirubin (mALBI) grade was 1 in 96 patients, 2a in 50, and 2b in 41. The number of HCV-related HCC cases was in 80, HBV in 32 and non-B and non-C in 75. In 51 patients, identification of vascular invasion to the first-order branch of the portal vein and/or major hepatic vein was confirmed. The median maximum tumor diameter was 5.1 cm (4.0-13.5 cm). In 76 patients, C-ion RT were treated for recurrence. With a median follow-up period of 25.9 months (range, 1.1-215.1), 2-year overall survival, progression-free survival and local control rates were 68.3% (95% confidence interval [CI], 64.7-72.0%), 39.0% (95% CI, 35.2 - 42.8%) and 86.7% (95% CI, 84.7 - 89.7%), respectively. Late adverse events were observed in 3 patients (1.6%) with Grade 3 liver dysfunction and in 3 patients (1.6%) with Grade 3 skin disorders, but there were no cases of Grade 4 or higher. Multivariate analysis of prognostic factors for overall survival revealed that mALBI grade in 2b(HR:3.13, 1.97-4.78, p<0.0001), tumor status in recurrent treatment (HR:1.50, 1.02-2.21, p = 0.039), the number of tumors in 2 or more (HR:2.16, 1.01-2.17, p = 0.045), and maximum tumor diameter in larger than 6 cm (HR:2.34, 1.50-3.61, p = 0.0001) were the predominant prognostic factors, while age, presence of vascular invasion, AFP and DCP were not. The safety and efficacy of C-ion RT for bulky (≥4cm) locally advanced HCC was demonstrated. These results suggested that C-ion RT may be a new treatment option for locally advanced bulky HCC with no curative treatment options.

Clinical impact of carbon-ion radiotherapy on hepatocellular carcinoma with Child-Pugh B cirrhosis.

Hepatocellular carcinoma (HCC) patients with Child-Pugh (CP)-B not eligible for surgery nor other focal therapy options due to impaired liver function, have very limited treatment options. This study aims to retrospectively investigate the toxicity and efficacy of Carbon-ion radiotherapy (C-ion RT) on HCC with CP-B patients. Patients with CP-B, no extrahepatic metastasis, and treated with C-ion RT between May 2000 and March 2020 were retrospectively extracted and included in this study. Sixty-nine lesions of 58 patients were included. The median follow-up duration was 20.5 (2.7-108) months. During follow-up, recurrence was observed in 43 patients, including 2 local recurrences and 39 intrahepatic recurrences beyond the irradiation field. A grade 3 acute hepatotoxicity was observed in one patient during the observation period. No acute or late adverse event of grade ≥4 was observed. Overall survival was 80.4% and 46.0% at 1 and 2 years, respectively, and the median survival time was 22.6 months. Local control rate was 96.4% at both 1 and 2 years, and progression-free survival was 38.6% and 6.9% at 1 and 2 years, respectively, with a median of 9.7 months. The C-ion RT showed low toxicity and good local effect in patients with HCC and CP-B. Therefore, C-ion RT could be an appropriate treatment for patients with HCC with poor liver function.

OC-0452 The role of RBE and LET in treatment efficacy of carbon ion radiotherapy for sacral chordoma

OC-0452 The role of RBE and LET in treatment efficacy of carbon ion radiotherapy for sacral chordoma

Two-Year Toxicity and Efficacy of Carbon Ion Radiotherapy in the Treatment of Localized Prostate Cancer: A Single-Centered Study.

BackgroundWe aimed at determining the safety and feasibility of spot-scanning carbon ion radiotherapy (CIRT) for patients with localized prostate cancer.MethodsWe enrolled 118 patients with localized prostate cancer who underwent treatment with spot-scanning CIRT at the Shanghai Proton and Heavy Ion Center (SPHIC) from January 2016 to December 2020. The dose was gradually increased from relative biological effectiveness (RBE)-weighted dose (DRBE) = 59.2–65.6 Gy in 16 fractions. The primary endpoint was the occurrence of acute and late toxicities, while the secondary endpoints were biochemical relapse-free survival (bRFS), distant metastasis-free survival (DMFS), prostate cancer-specific survival (PCSS), and overall survival (OS).ResultsThe median follow-up time was 30.2 months (4.8–62.7 months). Acute grade 1 and 2 genitourinary (GU) toxicities were 15.3% and 18.6%, while acute grade 1 and 2 gastrointestinal (GI) toxicities were 2.5% and 0%, respectively. Late grade 1 and 2 GU toxicities were 4.2% and 1.7%, respectively. No late GI toxicity was observed. Moreover, there were no cases of severe acute or late toxicity (≥ grade 3). No significant association were observed between the factors and the acute GU toxicities, except for clinical target volume (CTV) (p = 0.031) on multivariate analysis. The 2-year bRFS, DMFS, PCSS, and OS were 100%, 100%, 100%, and 98.8%, respectively.ConclusionThe 2-year outcomes were encouraging, providing additional and useful information on the feasibility and safety of spot-scanning CIRT for treating prostate cancer. Thus, we recommend long-term follow-up and prospective multicentered studies to reinforce the role of CIRT in the management of localized prostate cancer.

Efficacy and Safety of 4 Fractions of Carbon-Ion Radiation Therapy for Hepatocellular Carcinoma: A Prospective Study

Introduction: Prospective evidence supporting the safety and efficacy of carbon-ion radiotherapy (C-ion RT) for hepatocellular carcinoma (HCC) remains lacking. This prospective study aimed to evaluate the safety and efficacy of hypofractionated C-ion RT in patients with HCC. Methods: The inclusion criteria were as follows: (1) pathologically or clinically diagnosed HCC; (2) measurable tumor and tumor size ≤10 cm; (3) absence of major vascular invasion; (4) no extrahepatic metastasis; (5) the alimentary tract was not adjacent to the target lesion (>1 cm); (6) not suitable for or refusal to undergo surgery or local ablative therapies; (7) an interval ≥4 weeks from previous therapy; (8) no other intrahepatic lesion or at least 2 years after the previous curative therapy; (9) performance status score, 0–2; and (10) Child-Pugh score, 5–9. The prescribed C-ion RT dose was 52.8 Gy (relative biological effectiveness [RBE]) or 60.0 Gy (RBE) in 4 fractions. Results: In total, 35 patients with HCC were enrolled between October 2010 and May 2016. The median follow-up durations in the survivor group (n = 23) and in the whole cohort were 55.1 and 49.0 months, respectively. The 2-, 3-, and 4-year overall survival rates were 82.8%, 76.7%, and 69.4%, respectively. The 2-, 3-, and 4-year local control (LC) rates were 92.6%, 76.5%, and 76.5%, respectively. The median time-to-progression was 25.6 months (95% confidence interval, 13.7–37.5 months). Grade 4 or 5 toxicities were not observed. Grade 3 acute and late toxicities were observed in 2 patients. There was no significant deterioration in serum albumin, bilirubin, prothrombin time-international normalized ratio, platelet count, or Child-Pugh score after C-ion RT. Conclusion: Four fractions of C-ion RT for HCC did not yield serious adverse events and showed promising LC, thus making it a safe and effective modality for this type of malignancy.

Carbon Ion Radiotherapy for Locally Recurrent Rectal Cancer of Patients with Prior Pelvic Irradiation

BackgroundThis study aimed to assess the safety and efficacy of carbon-ion radiotherapy (CIRT) for salvage of previously X-ray-irradiated (XRT) locally recurrent rectal cancer (LRRC).MethodsBetween September 2005 and December 2017, 77 patients with LRRC were treated with CIRT re-irradiation. All the patients had received prior XRT with a median dose of 50.0 Gy (range 20–74 Gy), principally for neoadjuvant or adjuvant recurrence prophylaxis in 34 patients and for recurrence in 43 patients. The total CIRT dose of 70.4 Gy (RBE) (gray relative biologic effectiveness) was administered in 16 fixed fractions during 4 weeks (4.4 Gy [RBE] per fraction).ResultsAll the patients completed the scheduled treatment course. None of the patients received resection after CIRT. Acute grade 3 toxicities occurred for eight patients (10 %), including five grade 3 pelvic infections (2 involving pain and 1 involving neuropathy). Late grade 3 toxicities occurred for 16 patients (21 %): 13 with late grade 3 pelvic infections, 9 with gastrointestinal toxicity, 1 with skin toxicity, 2 with pain, and 4 with neuropathy. No grade 4+ toxicity was noted. The overall local control rates (infield + out-of-field recurrence) were 69 % at 3 years and 62 % at 5 years. In the planning target volume (PTV), the infield recurrence rates were 90 % and 87 % respectively. The control rates for regional recurrence were 85 % at 3 years and 81 % at 5 years. The median overall survival time was 47 months. The survival rates were 61 % at 3 years and 38 % at 5 years.ConclusionCarbon-ion re-irradiation of previously X-ray-irradiated locally recurrent rectal cancer appears to be safe and effective, providing good local control and survival advantage without unacceptable morbidity.

Effectiveness of Carbon Ion Radiation in Locally Advanced Pancreatic Cancer.

PurposeEffective treatment strategies for unresectable locally advanced pancreatic cancer (LAPC) patients are eagerly warranted. Recently, convincing oncological outcomes were demonstrated by carbon ion radiotherapy. Nevertheless, there is a lack of evidence for this modern radiation technique due to the limited number of carbon ion facilities worldwide. Here, we analyze feasibility and efficacy of carbon ion radiotherapy in the management of LAPC at Heidelberg Ion Beam Therapy Center (HIT).MethodsBetween 2015 and 2020, 21 LAPC patients were irradiated with carbon ions with a total dose of 48 Gy (RBE) in single doses of 4 Gy (RBE). Three patients (14%) were treated with concomitant chemotherapy with gemcitabine 300 mg/m2 body surface weekly. Toxicity rates were extracted from the charts. Overall survival, progression free survival, local control, and locoregional control were evaluated using Kaplan–Meier estimates.ResultsOne patient developed ascites CTCAE grade III during radiotherapy, which was related to a later histologically confirmed metachronous peritoneal carcinomatosis. No further higher-graded toxicity could be observed. The most common symptoms were nausea and abdominal pain. After a median estimated follow-up time of 19.1 months, the median progression free survival was 3.7 months, and the median overall survival was 11.9 months. The estimated 1-year local control and locoregional control rates were 89 and 84%, respectively.ConclusionCarbon ion radiotherapy of LAPC patients is safely feasible. Local tumor control rates were high. Nevertheless, compared to historical data, an overall survival improvement could not be observed. This could be explained by the poor prognosis of the selected underlying patients that mostly did not respond to prior chemotherapy as well as the early and frequent emergence of distant metastases that demonstrate the necessity of additional chemotherapy in further studies.

Carbon ion radiotherapy as definitive treatment in non-metastasized pancreatic cancer: study protocol of the prospective phase II PACK-study

BackgroundRadiotherapy is known to improve local tumor control in locally advanced pancreatic cancer (LAPC), although there is a lack of convincing data on a potential overall survival benefit of chemoradiotherapy over chemotherapy alone. To improve efficacy of radiotherapy, new approaches need to be evolved. Carbon ion radiotherapy is supposed to be more effective than photon radiotherapy due to a higher relative biological effectiveness (RBE) and due to a steep dose-gradient making dose delivery highly conformal.MethodsThe present Phase II PACK-study investigates carbon ion radiotherapy as definitive treatment in LAPC as well as in locally recurrent pancreatic cancer. A total irradiation dose of 48 Gy (RBE) will be delivered in twelve fractions. Concurrent chemotherapy is accepted, if indicated. The primary endpoint is the overall survival rate after 12 months. Secondary endpoints are progression free survival, safety, quality of life and impact on tumor markers CA 19–9 and CEA. A total of twenty-five patients are planned for recruitment over 2 years.DiscussionRecently, Japanese researches could show promising results in a Phase I/II-study evaluating chemoradiotherapy of carbon ion radiotherapy and gemcitabine in LAPC. The present prospective PACK-study investigates the efficacy of carbon ion radiotherapy in pancreatic cancer at Heidelberg Ion Beam Therapy Center (HIT) in Germany.Trial registrationThe trial is registered at ClinicalTrials.gov: NCT04194268 (Retrospectively registered on December, 11th 2019).

Moderately hypofractionated carbon ion radiotherapy for prostate cancer; a prospective observational study \u201cGUNMA0702\u201d

BackgroundCarbon ion Radiotherapy for prostate cancer is widely used, however reports are limited from single institute or short follow up. We performed a prospective observational study (GUNMA0702) to evaluate the feasibility and efficacy of carbon ion radiotherapy for localized and locally advanced prostate cancer.MethodsBetween June 2010 and August 2013, 304 patients with localized prostate cancer were treated, with a median follow-up duration of 60 months. All patients received carbon ion radiotherapy with 57.6 Gy (RBE) in 16 fractions over 4 weeks. Hormonal therapy was given according to the risk group. Toxicity was reported according to the Common Toxicity Criteria for Adverse Event, Version 4.0 by the National Cancer Institute.ResultsThe overall 5-year biochemical relapse-free rate was 92.7%, with rates of 91.7, 93.4, and 92.0% in low-risk, intermediate-risk, and high-risk patients, respectively. The 5-year local control and overall survival rates were 98.4 and 96.6%, respectively. Acute grade 3 or greater toxicity was not observed. Late grade 2 and grade 3 genitourinary and gastrointestinal toxicity rates were 9 and 0.3%, and 0.3, and 0%, respectively.ConclusionsThe present protocol of carbon ion radiotherapy for prostate cancer provided low genitourinary and gastrointestinal toxicity with good biochemical control within 5 years.Trial registrationUniversity Medical Information Network Clinical Trial Registry number: UMIN000003827.

Safety and Efficacy of Carbon-ion Radiotherapy Alone for Stage III Non-small Cell Lung Cancer.

We evaluated the efficacy and safety of carbon-ion radiotherapy (CIRT) alone for Stage III non-small-cell lung cancer (NSCLC). Data of 65 patients (median age=73 years) with Stage III NSCLC who underwent CIRT alone in the QST Hospital, Chiba, Japan, between 1997 and 2015 were retrospectively analysed. The median dose was 72.0 Gy (relative biological effectiveness). The median follow-up was 27.6 months (range=1.6-207.7 months). Two-year local control, progression-free survival (PFS), and overall survival (OS) rates were 73.9%, 38.6%, and 54.9%, respectively. Overall, 1 (2%), 4 (6%), and 1 (2%) patient developed Grade 4 (mediastinal haemorrhage), Grade 3 (radiation pneumonitis), and Grade 3 (bronchial fistula) toxicities, respectively. On univariate analysis, clinical T and N stage and CIRT timing were significant predictors of PFS and OS; clinical target volume was a significant predictor of PFS. CIRT alone is effective with acceptable toxicity for Stage III NSCLC.

Long-term outcomes and toxicities of carbon-ion radiotherapy in malignant tumors of the sphenoid sinus.

BackgroundMost of the primary sphenoid sinus tumors present with locally advanced stages with involvement of adjacent critical structures and are not amenable to radical resection. We sought to evaluate the safety and efficacy of carbon‐ion radiotherapy (C‐ion RT) for sphenoid sinus malignancies.MethodsThis is a retrospective analysis of 22 patients of primary sphenoid carcinomas treated with definitive C‐ion RT.ResultsAdenoid cystic carcinoma was the most common histology (15 patients, 68.2%). The median follow‐up of this cohort was 48.5 months. The actuarial local control and overall survival at 5 years were 51.0% and 62.7%, respectively. Grade 4 visual impairment and grade 4 brain necrosis were seen in six and one patient, respectively.ConclusionC‐ion RT can provide a reasonably good clinical outcome in locally advanced sphenoid sinus malignancies with a marginally higher late toxicity profile because of extremely close proximity of the target volume to critical structures.

Carbon-Ion Radiotherapy for Bone and Soft Tissue Tumors; Analysis of 92 Patients at Gunma University Heavy Ion Medical Center (GHMC)

To retrospectively evaluate the feasibility and efficacy of carbon-ion radiotherapy (C-ion RT) for unresectable bone and soft tissue tumors treated in Gunma University Heavy Ion Medical Center (GHMC). A total 92 patients with bone or soft tissue tumors treated with C-ion RT between November 2011 and December 2018 in GHMC were retrospectively evaluated. In C-ion RT, 70.4 Gy(RBE) was administrated as the standard total dose for sarcomas; 67.2 Gy(RBE) for sacrococcygeal chordomas; 64.0 Gy(RBE) for spinal bone tumors, in 16 fractions over 4 weeks. Local control rate (LCR), survival outcomes, acute and late adverse events were analyzed. The curves of LCR and overall survival rates (OS) were calculated by Kaplan-Meier method. The median age at the C-ion RT was 68 years (range, 25-90 years). Median follow-up time was 28.5 months (range, 1-97 months). Histologically, 31 patients had chordoma, 13 patients had UPS or MFH, 11 patients had liposarcoma, 8 patients had chondrosarcoma and 7 patients had osteosarcoma. The 3-year LCR and OS in all patients were 85% and 70%, respectively. The 3-year LCR and OS of 50 patients with bone tumor were 95% and 82%, and those of 42 patients with soft tissue tumors were 72% and 51%. The 3-year LCR and OS of 31 patients with chordoma were 96%, 90%; those of 13 patients with UPS or MFH were 45%, 62%; those of 11 patients with liposarcoma were 88%, 36%; those of 8 patients with chondrosarcoma were 86%, 67%; and the 2-year LCR and OS of 7 patients with osteosarcoma were 100%, 46%. The 3-year LCR and OS by volume of clinical target volume (CTV) were 100%, 100% in under 100cc (n=6), 76%, 68% in between 100cc and 500cc (n=29), 76%, 37% in over 500cc (n=24), respectively. There were no patients with Grade 3 or above acute adverse events. The Grade 3 or above late adverse events were shown in 7 patients. The results of this study showed that C-ion RT must be an alternative treatment option for unresectable bone and soft tissue tumors. Both the LCR and OS were influenced by CTV volume.

Carbon-ion radiotherapy for cholangiocarcinoma: a multi-institutional study by and the Japan carbon-ion radiation oncology study group (J-CROS).

To evaluate the safety and efficacy of carbon-ion radiotherapy (CIRT) for cholangiocarcinoma via a multicenter retrospective study. Clinical data were collected from patients with cholangiocarcinoma who had received CIRT at one of four treating institutions in Japan. Of 56 eligible patients, none received surgery for cholangiocarcinoma before or after CIRT. The primary endpoint was overall survival (OS). Based on the tumor site, the 56 cases were categorized as intrahepatic cholangiocarcinoma (IHC) (n=27) or perihilar cholangiocarcinoma (PHC) (n=29). In all patients, the median tumor size was 37 (range, 15‒110) mm, and the most commonly prescribed dose was 76 Gy (relative biological effectiveness) in 20 fractions. The median survival was 14.8 (range, 2.1-129.2) months, and the 1- and 2-year OS rates were 69.7% and 40.9%, respectively. The median survival times of the patients with IHC and those with PHC were 23.8 and 12.6 months, respectively. Both univariate and multivariate analyses revealed that cholangitis pre-CIRT and Child‒Pugh class B were significant prognostic factors for an unfavorable OS. Of four patients who died of liver failure, one with IHC was suspected to have radiation-induced liver disease because of newly developed ascites, and died at 4.3 months post-CIRT. Grade 3 CIRT-related bile duct stenosis was observed in one IHC case. No other CIRT-related severe adverse events, including gastrointestinal events, were observed. These results suggest that CIRT yields relatively favorable treatment outcomes, especially for patients with IHC, and acceptable toxicities were observed in patients with cholangiocarcinoma who did not receive surgery.

Feasibility of Carbon Ion Radiotherapy in the Treatment of Gynecological Melanoma.

Malignant melanoma of the lower genital tract is a rare disease known to have a poor prognosis. Because of the high rate of distant metastasis and unsatisfactory survival benefit, a more conservative treatment approach, instead of extensive surgery, may be warranted. Gynecological melanoma is a radioresistant tumor, an ideal disease to test the biological efficacy of carbon ion radiotherapy (CIRT). To report our preliminary experience with CIRT in the treatment of gynecological melanoma at the National Center of Oncological Hadrontherapy (CNAO). Between January 2016 and February 2017, four patients were admitted for CIRT at CNAO. A case of cervical melanoma was treated with palliative aim because of large volume macroscopic disease, while three cases of vaginal melanoma were irradiated with a total dose of 68.8 Gy (relative biological effectiveness) in 16 fractions delivered over 4 weeks (4 days a week). The age of women ranged between 49 and 72 (median=60.5 years) years. Treatment was well tolerated in all patients and all women completed the scheduled treatment course. During CIRT, toxicity was mild. For patients with vaginal disease, local control was 10.23 and 12.6 months, while that for cervical malignant melanoma was 7.3 months. All patients experienced systemic progression, with median distant metastasis-free survival of 11.7 months. The median overall survival for the whole patient group was 11.41 months. In our first experiences, CIRT appears to be a safe non-invasive option for malignant melanoma of the lower genital tract, but more data and longer follow-up are necessary in order to evaluate the effectiveness and late effects.

A retrospective multicenter study of carbon-ion radiotherapy for external auditory canal and middle ear carcinomas.

BackgroundWe conducted a retrospective multicenter study to assess the clinical outcomes of carbon‐ion radiotherapy (CIRT) for head and neck malignancies (Japan Carbon‐Ion Radiation Oncology Study Group [J‐CROS] study: 1402 HN). We aimed to evaluate the safety and efficacy of CIRT in patients with external auditory canal (EAC) and middle ear (ME) carcinomas.MethodsThirty‐one patients treated with CIRT at four Japanese institutions were analyzed. Fourteen patients (45.2%) had squamous cell carcinomas, 13 (41.9%) had adenoid cystic carcinomas, and four (12.9%) had other types. Nineteen (61.3%), six (19.4%), three (9.7%), and three (9.7%) patients had T4, T3, T2, and T1 disease, respectively. All patients had N0M0 status. The median radiation dose was 64 Gy (relative biological effectiveness) in 16 fractions. The median gross tumor volume was 33.3 mL.ResultsThe median follow‐up period was 18.4 months (range, 5.1‐85.6). The 1‐ and 3‐year local control and overall survival rates were 75.0% and 55.0% and 79.3% and 58.7%, respectively. Regarding grade 3 or higher toxicities, three patients (9.7%) had grade 3 dermatitis, one (3.2%) had grade 3 mucositis, and two (6.5%) had grade 3 central nervous necrosis (ie, radiation‐induced brain necrosis). No grade 4 or worse reactions were observed.ConclusionCIRT was effective for EAC and ME carcinomas.

Genistein sensitizes glioblastoma cells to carbon ions via inhibiting DNA-PKcs phosphorylation and subsequently repressing NHEJ and delaying HR repair pathways

Background and purposePreviously, we found genistein could sensitize cancer cells to low linear energy transfer (LET) X-rays via inhibiting DNA-PKcs activities. Especially, high-LET heavy ion produces more DNA double strand breaks (DSBs) than low-LET radiation. Thus, the study was designed to investigate the detailed molecular mechanisms of genistein on sensitizing cancer cells to heavy ions. Materials and methodsHuman glioblastoma (GBM) cell lines with or without genistein pre-treatment were irradiated with high-LET carbon ions. Cell survival was determined with colony formation assay. DNA DSBs were evaluated by means of detecting γ-H2AX foci and immuno-blotting DSB repair proteins, cell apoptosis was detected using Annexin V and PI staining. The interaction of genistein with DNA-PKcs activation site was estimated by molecular docking in the autodock software. ResultsGenistein sensitized DNA-PKcs proficient GBM cells to high-LET carbon ions via delaying the clearance of γ-H2AX foci. Genistein was physically bound to DNA-PKcs and functionally inhibited the phosphorylation of DNA-PKcs. Consequently, the non-homologous end joining (NHEJ) repair of DSBs was inhibited and the homologous recombination (HR) repair was delayed by genistein, thereby leading to an increase in apoptosis in DNA-PKcs proficient GBM cells after irradiation. ConclusionOur study demonstrated that genistein holds promise as a radiosensitizer for enhancing the efficacy of carbon ion radiotherapy against DNA-PKcs proficient GBM via inhibiting DNA-PKcs phosphorylation and subsequently repressing NHEJ and delaying HR repair pathways.

Carbon-ion radiotherapy for inoperable endometrial carcinoma.

This is a pooled analysis to evaluate the toxicity and efficacy of carbon-ion radiotherapy (C-ion RT) for inoperable endometrial carcinoma. Eligible patients had previously untreated Stage I–III endometrial carcinoma without para-aortic lymph node metastasis. Total dose to the tumor was 62.4–74.4 Gy [relative biological effectiveness (RBE)] in 20 fractions, and the dose to the gastrointestinal tract was limited to <60 Gy (RBE). Intracavitary brachytherapy was not combined in the present study. Fourteen patients with endometrial carcinoma were analyzed. Ten of the 14 patients were judged medically inoperable, and the others refused surgery. The numbers of patients with Stage I, II and III disease were 1, 9 and 4, respectively. Tumor size was 3.8–13.8 cm in maximum diameter. Median follow-up periods for all patients and surviving patients were 50 months (range, 12–218 months) and 78 months (range, 23–218 months), respectively. Two of three patients receiving 62.4–64.8 Gy (RBE) had local recurrence whereas none of 11 patients receiving 68.0 Gy (RBE) or more had local recurrence. Three patients developed distant metastases and one of them also had local recurrence. The 5-year local control, progression-free survival, overall survival, and cause-specific survival rates were 86%, 64%, 68% and 73%, respectively. No patient developed Grade 3 or higher acute or late toxicity. The present study showed that C-ion RT alone could be a safe and curative treatment modality for inoperable endometrial carcinoma.

Nano-Vesicles are a Potential Tool to Monitor Therapeutic Efficacy of Carbon Ion Radiotherapy in Prostate Cancer.

Exosomes are nano-vesicles that contribute to the effectiveness of many treatments. The aim of this study was to identify profiles of microRNA (miRNA) contained in serum exosomes that are differentially regulated in patients with prostate cancer undergoing carbon ion radiotherapy (CIRT). RNA was extracted from serum exosomes of eight patients with localized prostate cancer before and after CIRT, and miRNA was analyzed by the next generation sequencing. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the major signaling pathways associated with the proliferation of prostate cancer cells, such as MAPK, PI3K-AKT, mTOR, and AMPK may be implicated in the mechanism of CIRT action. Notably, 57 miRNAs present in serum exosomes were significantly altered after application of CIRT. A high pre-CIRT expression level of specific miRNAs (miR-493-5p, miR-323a-3p, miR-411-5p, miR-494-3p, miR-379-5p, miR-654-3p, miR-409-3p, miR-543, and miR-200c-3p) predicted therapeutic benefit of CIRT (P < 0.05). Post-CIRT expression of miR-654-3p and miR-379-5p was also associated with CIRT efficacy (P < 0.05). These results suggest that the anti-prostate cancer mechanisms elicited by CIRT at the molecular level may involve exosomal miRNAs. Furthermore, specific miRNAs in serum exosomes, particularly miR-654-3p and miR-379-5p, may serve as promising non-invasive biomarkers predicting efficacy of CIRT for prostate cancer.