Risk factors of local control in adrenal metastases treated by stereotactic body radiation therapy - a systematic review and meta-analysis

Purpose

This study is aimed to explore risk factors affect the therapy outcomes of adrenal metastases (AM) for stereotactic body radiation therapy (SBRT) and guide clinical dose selection.

Methods and materials

PubMed, Embase and Web of Science were searched in September 22, 2022 in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). Subgroup analysis and meta-regression were used to search for sources of heterogeneity and identify risky outcomes factors. Publication bias test and sensitivity analysis were also conducted.

Results

Thirty-three studies with full text from 2009 to 2022 about AM with SBRT on 1483 patients were included. Pooled 1- and 2-year local control (LC) and overall survival(OS) were 81.7% (95% confidence interval [CI], 75.6%-86.5%), 62.8% (95% CI, 53.8%-71.8%), 67.4% (95%CI, 61.8%-73.1%) and 46.5% (95%CI, 40.4%-52.6%), respectively. Biological effective dose (BED, α/β=10Gy) and dose per fraction affected 1-year LC (Qm=23.89, 15.10; P<0.0001, 0.0001). In the range of 60-80Gy (BED10), the group of dose per fraction ≥ 9Gy achieved the excellent 1-year LC (< 9Gy: ≥ 9Gy =78%, 91%; χ2 = 10.16, P = 0.001). Tracking technology significantly affected 1- and 2-year OS (Qm = 5.73, 8.75; P = 0.017, 0.003) and high tracking adoption group showed excellent 1- and 2- year OS (78.7% [95%CI, 68.6%- 88.9%]; and 62.9% [95%CI, 53.1%-72.7%]).

Conclusion

Increasing the dose per fraction appropriately may help control locally AM lesious. Tracking technology might contribute to improve survival of advanced patients with AM. But these results need prospective studies to verify them.

Physical and biological beam modeling for carbon beam scanning at Osaka Heavy Ion Therapy Center

We have developed physical and biological beam modeling for carbon scanning therapy at the Osaka Heavy Ion Therapy Center (Osaka HIMAK). Carbon beam scanning irradiation is based on continuous carbon beam scanning, which adopts hybrid energy changes using both accelerator energy changes and binary range shifters in the nozzles. The physical dose calculation is based on a triple Gaussian pencil-beam algorithm, and we thus developed a beam modeling method using dose measurements and Monte Carlo simulation for the triple Gaussian. We exploited a biological model based on a conventional linear-quadratic (LQ) model and the photon equivalent dose, without considering the dose dependency of the relative biological effectiveness (RBE), to fully comply with the carbon passive dose distribution using a ridge filter. We extended a passive ridge-filter design method, in which carbon and helium LQ parameters are applied to carbon and fragment isotopes, respectively, to carbon scanning treatment. We then obtained radiation quality data, such as the linear energy transfer (LET) and LQ parameters, by Monte Carlo simulation. The physical dose was verified to agree with measurements to within ±2% for various patterns of volume irradiation. Furthermore, the RBE in the middle of a spread-out Bragg peak (SOBP) reproduced that from passive dose distribution results to within ±1.5%. The developed carbon beam modeling and dose calculation program was successfully applied in clinical use at Osaka HIMAK.

Changes in sexual function and serum testosterone levels in patients with prostate cancer after image-guided proton therapy

Since sexual function and testosterone levels after image-guided proton therapy (IGPT) have not yet been examined in detail, we prospectively evaluated changes before and after IGPT. Among patients treated with IGPT with or without combined androgen blockade (CAB) therapy between February 2013 and September 2014, patients who agreed to participate in the study and were followed up for >3 years after IGPT were evaluated. Serum testosterone levels were regularly measured together with prostate-specific antigen (PSA) levels before and after IGPT. The Erection Hardness Score (EHS) and the sexual domain summary, function subscale and bother subscale of the sexual domain in the Expanded Prostate Cancer Index Composite (EPIC) were assessed. There were 38 low-risk, 46 intermediate-risk and 43 high- or very-high-risk patients (NCCN classification). Although serum testosterone levels in low-risk patients did not decrease after IGPT, reductions were observed in the average EHS and the sexual domain summary score of the EPIC. In intermediate-, high- and very-high-risk patients, testosterone and PSA levels both increased following the termination of CAB after IGPT, and the average EHS increased. The sexual domain summary score gradually increased, but not above minimally important differences. In intermediate-risk patients, the function subscale increased from 4.4 to 14.8 (P < 0.05) 12 months after IGPT and reached a plateau after 60 months. The results of the present study would suggest the potential of IGPT, and further prospective studies to directly compare IGPT with other modalities are warranted.

Image-Guided Proton Therapy for Elderly Patients with Hepatocellular Carcinoma: High Local Control and Quality of Life Preservation

This study retrospectively investigated the efficacy and safety of image-guided proton therapy (IGPT) for elderly (≥80 years old) hepatocellular carcinoma (HCC) patients. Proton therapy was performed using respiratory-gated and image-guided techniques. Seventy-one elderly HCC patients were treated using IGPT. The Child-Pugh score was A5 in 49 patients, A6 in 15, and B7-9 in 7. Forty-seven patients with a peripherally located tumor were administered 66 gray relative biological effectiveness (GyRBE) in 10 fractions, whereas 24 with a centrally located tumor received 72.6 GyRBE in 22 fractions. The median follow-up period of surviving patients was 33 months (range: 9-68). Two-year overall survival (OS) and local control (LC) rates estimated by the Kaplan-Meier method were 76% (95% confidence interval: 66-87%) and 88% (80-97%), respectively. According to the Common Terminology Criteria for Adverse Events version 4.0, no grade 2 or higher radiation-induced liver disease was observed, and only 1 patient developed grade 3 dermatitis. The quality of life score (European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 version 3.0, QLQ-HCC18, and SF-36) did not change after 1 year, except for the three-mental component summary (SF-36, improvement). IGPT is a safe and effective treatment for HCC in elderly patients.

Proton therapy for non-squamous cell carcinoma of the head and neck: planning comparison and toxicity

To investigate optimal treatment planning using proton beams for non-squamous cell carcinoma of the head and neck (NSCHN), the dose distributions of plans involving pencil beam scanning (PBS) with or without a patient-specific aperture system (PSAS), passive-scattering proton therapy (PSPT) and X-ray intensity-modulated radiotherapy (IMRT) were compared. As clinical results, toxicities of PBS with PSAS, including changes in quality of life, were reported. Between April 2014 and August 2016, a total of 30 patients were treated using PBS with PSAS. In 20 patients selected at random, the dose distributions of PBS with or without the PSAS, PSPT and IMRT plans were compared. Neutron exposure by proton therapy was calculated using a Monte Carlo simulation. Toxicities were scored according to CTCAE ver. 4.0. Patients completed EORTC quality of life survey forms (QLQ-C30 and QLQ-HN35) before and 0-12 months after proton therapy. The 95% conformity number of PBS with the PSAS plan was the best, and significant differences were detected among the four plans (P < 0.05, Bonferroni tests). Neutron generation by PSAS was ~1.1-fold higher, but was within an acceptable level. No grade 3 or higher acute dermatitis was observed. Pain, appetite loss and increased weight loss were more likely at the end of treatment, but recovered by the 3 month follow-up and returned to the pretreatment level at the 12 month follow-up. PBS with PSAS reduced the penumbra and improved dose conformity in the planning target volume. PBS with PSAS was tolerated well for NSCHN.

A phase II trial of S-1 plus cisplatin with concurrent proton-beam therapy for locally advanced non-small cell lung cancer

e20070

Background: Concurrent chemo-radiotherapy is the standard treatment for locally advanced (LA) non-small cell lung cancer (NSCLC). Recent phase II studies have demonstrated that S-1 plus cisplatin (CDDP) with concurrent radiotherapy yields promising results against LA NSCLC. Proton-beam therapy (PBT) is an alternative modality that is expected to reduce toxic effects against normal tissues compared with X-ray radiotherapy. We conducted a phase II trial of S-1 plus CDDP combined with concurrent PBT for patients (pts) with LA NSCLC. Methods: The eligibility criteria included unresectable stage III NSCLC, chemo-naïve status, PS 0 or 1, and age < 75 years. Pts received CDDP (80 mg/m2) on day 1 and S-1 (30-40 mg/m2 twice daily) on days 1 to 14, q4w, up to 4 cycles, plus concurrent PBT at a total dose of 70 GyE in 35 fractions for primary lesion and 66 GyE in 33 fractions for lymph node metastasis. PBT was performed using respiratory-gated and image-guided techniques, and adaptive plans were implemented according to a verification plan at 10, 20, and 30 days. Results: Thirty-two pts were enrolled between August 2013 and December 2016. The patient characteristics were as follows: median age, 66 (31-74); male/female, 24/8; PS 0, 26 pts; stage IIIA/IIIB, 19/13; non-squamous histology, 17 (53%). Twenty pts were out of indication for radical chemo-radiation with X rays. All 4 cycles of S-1 plus CDDP could be completed in 24 pts and the median number of cycles was 3.3 (range: 2 to 4). Grade 3/4 toxicities per pt were: neutropenia 28%, anemia 13%, thrombocytopenia 9.4%, fatigue, anorexia, esophagitis, mucositis and enteritis 3.1%, and radiation pneumonitis 0%. One case of febrile neutropenia was observed. PR + CR was achieved in 24 of 28 evaluable pts. The median PFS was 12.5 months, and 2-year OS was 63%, with a median follow-up period of 19.5 (range: 1.5-40.0) months. Conclusions: Concurrent chemo-PBT using S-1 plus CDDP with image-guided and adaptive techniques is considered to be effective and well tolerated for LA NSCLC. Further evaluations in a large randomized controlled trial are warranted.

Initial clinical experience with scanned proton beams at the Italian National Center for Hadrontherapy (CNAO)

We report the initial toxicity data with scanned proton beams at the Italian National Center for Hadrontherapy (CNAO). In September 2011, CNAO commenced patient treatment with scanned proton beams within two prospective Phase II protocols approved by the Italian Health Ministry. Patients with chondrosarcoma or chordoma of the skull base or spine were eligible. By October 2012, 21 patients had completed treatment. Immobilization was performed using rigid non-perforated thermoplastic-masks and customized headrests or body-pillows as indicated. Non-contrast CT scans with immobilization devices in place and MRI scans in supine position were performed for treatment-planning. For chordoma, the prescribed doses were 74 cobalt grey equivalent (CGE) and 54 CGE to planning target volume 1 (PTV1) and PTV2, respectively. For chondrosarcoma, the prescribed doses were 70 CGE and 54 CGE to PTV1 and PTV2, respectively. Treatment was delivered five days a week in 35-37 fractions. Prior to treatment, the patients' positions were verified using an optical tracking system and orthogonal X-ray images. Proton beams were delivered using fixed-horizontal portals on a robotic couch. Weekly MRI incorporating diffusion-weighted-imaging was performed during the course of proton therapy. Patients were reviewed once weekly and acute toxicities were graded with the Common Terminology Criteria for Adverse Events (CTCAE). Median age of patients = 50 years (range, 21-74). All 21 patients completed the proton therapy without major toxicities and without treatment interruption. Median dose delivered was 74 CGE (range, 70-74). The maximum toxicity recorded was CTCAE Grade 2 in four patients. Our preliminary data demonstrates the clinical feasibility of scanned proton beams in Italy.

Preliminary calculation of RBE-weighted dose distribution for cerebral radionecrosis in carbon-ion treatment planning

Cerebral radionecrosis is a significant side effect in radiotherapy for brain cancer. The purpose of this study is to calculate the relative biological effectiveness (RBE) of carbon-ion beams on brain cells and to show RBE-weighted dose distributions for cerebral radionecrosis speculation in a carbon-ion treatment planning system. The RBE value of the radionecrosis for the carbon-ion beam is calculated by the modified microdosimetric kinetic model on the assumption of a typical clinical α/β ratio of 2 Gy for cerebral radionecrosis in X-rays. This calculation method for the RBE-weighted dose is built into the treatment planning system for the carbon-ion radiotherapy. The RBE-weighted dose distributions are calculated on computed tomography (CT) images of four patients who had been treated by carbon-ion radiotherapy for astrocytoma (WHO grade 2) and who suffered from necrosis around the target areas. The necrotic areas were detected by brain scans via magnetic resonance imaging (MRI) after the treatment irradiation. The detected necrotic areas are easily found near high RBE-weighted dose regions. The visual comparison between the RBE-weighted dose distribution and the necrosis region indicates that the RBE-weighted dose distribution will be helpful information for the prediction of radionecrosis areas after carbon-ion radiotherapy.

A study on the prognostic evaluation of carbon ion radiotherapy for head and neck adenocarcinoma with C-11 methionine PET

PURPOSE

Carbon ion radiotherapy (CIRT) has been developed, and a phase I/II CIRT trial has been conducted in patients with adenocarcinoma in the head and neck region. We evaluated whether the L-methyl [11C]-methionine (MET) uptake could be an early predictor for local recurrence, metastasis, and the prognosis in patients with adenocarcinoma in the head and neck region.

METHODS

Twenty-six patients were prospectively studied by MET-positron emission tomography (PET) before and about 1 month after CIRT. The tumor MET uptake was measured with the semiquantitative tumor to normal tissue ratio (TNR). The tumor TNR and relevant clinical parameters were then evaluated by both univariate and multivariate analyses.

RESULTS

The average TNRs before and after the treatment were 6.2 (± 2.2) and 3.9 (± 1.7), respectively, and significant differences were observed between them. In a univariate analysis, both local recurrence and metastasis were observed more frequently in the group with a higher TNR before and after the treatment than a lower TNR, and the prognosis was also poor. The cut-off values were 9.3, 4.9, and 5.1 before the treatment and 4.9, 4.2, and 4.3 after the treatment, respectively. In the rate of TNR changes before and after the treatment, metastasis was observed more frequently in the group with lower rates of change, and the prognosis was poor. The cut-off values for metastasis and prognosis determination were 18.0% and 16.9%, respectively. In a multivariate analysis, significant differences were observed for all relationships except for the relationship between the TNR before the treatment and local recurrence. Significant differences were observed for metastasis and prognosis in the rate of TNR changes before and after the treatment.

CONCLUSIONS

The determination of treatment effectiveness using TNR in CIRT for head and neck adenocarcinoma is an independent factor for predicting local recurrence, the incidence of metastasis, and the prognosis. MET-PET is therefore considered to be useful for determining the treatment effectiveness in patients with head and neck adenocarcinoma undergoing CIRT.

Comparison of efficacy and toxicity of short-course carbon ion radiotherapy for hepatocellular carcinoma depending on their proximity to the porta hepatis

BACKGROUND AND PURPOSE

To compare the efficacy and toxicity of short-course carbon ion radiotherapy (C-ion RT) for patients with hepatocellular carcinoma (HCC) in terms of tumor location: adjacent to the porta hepatis or not.

MATERIALS AND METHODS

The study consisted of 64 patients undergoing C-ion RT of 52.8 GyE in four fractions between April 2000 and March 2003. Of these patients, 18 had HCC located within 2 cm of the main portal vein (porta hepatis group) and 46 patients had HCC far from the porta hepatis (non-porta hepatis group). We compared local control, survival, and adverse events between the two groups.

RESULTS

The 5-year overall survival and local control rates were 22.2% and 87.8% in the porta hepatis group and 34.8% and 95.7% in the non-porta hepatis group, respectively. There were no significant differences (P=0.252, P=0.306, respectively). Further, there were no significant differences in toxicities. Biliary stricture associated with C-ion RT did not occur.

CONCLUSIONS

Excellent local control was obtained independent of tumor location. The short-course C-ion RT of 52.8 GyE in four fractions appears to be an effective and safe treatment modality in the porta hepatis group just as in the non-porta hepatis group.

Role of glucose metabolism and cellularity for tumor malignancy evaluation using FDG-PET/CT and MRI

OBJECTIVE

Standardized uptake value (SUV) is affected by many factors. In that respect, the brain reference index (BRI: regions of interest of tumor/regions of interest of cerebellum) is one of the quantitative approaches to eliminate the variety of factors that affect SUV. MRI pulse sequence findings can also provide information about tissue cellularity. This information is useful for evaluating the malignancy of lesions. We evaluated the role of glucose metabolism and cellularity for the diagnosis of pancreatic tumor malignancy.

METHOD

We performed a radionuclide 2-(18)F-fluoro-2-deoxyglucose ((18)F-FDG) uptake analysis and a signal intensity analysis using MRI on 16 presurgery patients with either proven or suspected pancreatic cancer. The tumor glucose metabolism was evaluated with SUV and BRI in an FDG-PET study. Tumor cellularity was determined with the MRI factors, apparent diffusion coefficient (ADC), T2 value and tumor to nontumor ratio of proton density. We compared these results with the pathological findings.

RESULTS

SUV (= 0.855), BRI ( =0.875), and ADC ( =0.830) showed a larger the area under the curve than T2 value (= 0.582) and tumor to nontumor ratio of proton density ( = 0.786) according to the receiver operating characteristics analysis, and we therefore considered that these three factors were better indexes for the diagnosis of tumor malignancy. SUV and BRI had a high specificity. In contrast, ADC had a high sensitivity.

CONCLUSION

The glucose metabolism with PET/CT and cellularity with MRI are different indexes for the diagnosis of tumor malignancy. Both provide necessary information for making an accurate diagnosis. Using both types of information may therefore help in obtaining a highly accurate diagnosis.

Compensatory enlargement of the liver after treatment of hepatocellular carcinoma with carbon ion radiotherapy - relation to prognosis and liver function

BACKGROUND AND PURPOSE

To examine whether liver volume changes affect prognosis and hepatic function in patients treated with carbon ion radiotherapy (CIRT) for hepatocellular carcinoma (HCC).

MATERIAL AND METHODS

Between April 1995 and March 2003, among the cases treated with CIRT, 43 patients with HCC limited to the right hepatic lobe were considered eligible for the study. The left lateral segment was defined as the non-irradiated region. Liver volume was measured using contrast CT at 0, 3, 6, and 12 months after CIRT. We examined serum albumin, prothrombin activity, and total bilirubin level as hepatic functional reserve.

RESULTS

After CIRT, the non-irradiated region showed significant enlargement, and enlarged volume of this region 3 months after CIRT 50 cm(3) was a prognostic factor. The 5-year overall survival rates were 48.9% in the larger enlargement group (enlarged volume of non-irradiated region 3 months after CIRT > or =50 cm(3)) and 29.4% in the smaller enlargement group (as above, <50 cm(3)). The larger enlargement group showed better hepatic functional reserve than the smaller enlargement group 12 months after CIRT.

CONCLUSIONS

This study suggests that compensatory enlargement in the non-irradiated liver after CIRT contributes to the improvement of prognosis.

Carbon ion radiotherapy: clinical experiences at National Institute of Radiological Science (NIRS)

In June 1994, the world's first clinical center offering carbon ion radiotherapy opened at the National Institute of Radiological Science (NIRS), Japan. Among several types of ion species, carbon ions were chosen for cancer therapy because they were judged to have the most optimal properties in terms of superior physical and biological characteristics. As of March 2010, 5,196 patients have been registered for carbon ion radiotherapy. Clinical results have shown that carbon ion radiotherapy has the potential to provide a sufficient radiation dose to the tumor, while having acceptable morbidity in the surrounding normal tissues. Tumors that appear to respond favorably to carbon ions include locally advanced tumors as well as histologically non-squamous cell tumor types such as adenocarcinoma, adenoid cystic carcinoma, malignant melanoma, hepatoma, and bone/soft tissue sarcoma. By taking advantage of the unique properties of carbon ions, treatment with small fractions within a short treatment period has been successfully carried out for a variety of tumors. This means that carbon ion radiotherapy can offer treatment for larger numbers of patients than is possible with other modalities over the same time period.

Carbon ion radiotherapy for elderly patients 80 years and older with stage I non-small cell lung cancer

Surgical resection is the standard treatment for stage I non-small cell lung cancer (NSCLC). However, elderly patients with NSCLC often suffer from other conditions, such as chronic obstructive pulmonary disease (COPD) or cardiovascular disease, and are not suitable candidates for surgery. Different modalities to treat stage I NSCLC have been developed, such as stereotactic radiotherapy (SRT), proton beam radiotherapy and carbon ion radiotherapy (CIRT). Between April 1999 and November 2003, we treated 129 patients with stage I NSCLC using CIRT. In this study, we focused on 28 patients aged 80 years and older who underwent CIRT, and analyzed the effectiveness of CIRT in treating their lung cancer and the impact on their activity of daily life (ADL). The 5-year local control rate for these patients was 95.8%, and the 5-year overall survival rate was 30.7%, but there were no patients who started home oxygen therapy or had decreased ADL. Our data demonstrate that CIRT was effective in treating elderly patients with stage I NSCLC.

Carbon ion radiation therapy for primary renal cell carcinoma: initial clinical experience

PURPOSE

Renal cell carcinoma (RCC) is known as a radioresistant tumor, and there are few reports on radiotherapy for primary RCC. We evaluated the efficacy of carbon ion radiotherapy (CIRT) for patients with RCC.

METHODS AND MATERIALS

Data for patients with RCC who received CIRT were analyzed. A median total dose of 72 GyE (gray equivalents) in 16 fractions was administered without any additional treatment. Clinical stage was determined based on TNM classification by the International Union Against Cancer (UICC). Local recurrence was defined as definite tumor regrowth after treatment.

RESULTS

Data for 10 patients were included in the analyses, including 7 patients with Stage I and 3 patients with Stage IV (T4NxM0 or TxN2M0) disease. The median maximum diameter of the tumor was 43 mm (24-120 mm). The median follow-up for surviving patients was 57.5 months (9-111 months). The 5-year local control rate, progression-free survival rate, cause-specific survival rate, and overall survival rates were 100%, 100%, 100%, and 74%, respectively. Interestingly, treated tumors showed very slow shrinkage, and the tumor in 1 case has been shrinking for 9 years. One patient with muscular invasion (T4 tumor) developed Grade 4 skin toxicity, but no other toxicity greater than Grade 2 was observed.

CONCLUSIONS

This is one of the few reports on curative radiotherapy for primary RCC. The response of the tumor to treatment was uncommon. However despite inclusion of T4 and massive tumors, favorable local controllability has been shown. The results indicate the possibility of radical CIRT, as well as surgery, for RCC.

Haplotype-based analysis of genes associated with risk of adverse skin reactions after radiotherapy in breast cancer patients

PURPOSE

To identify haplotypes of single nucleotide polymorphism markers associated with the risk of early adverse skin reactions (EASRs) after radiotherapy in breast cancer patients.

METHODS AND MATERIALS

DNA was sampled from 399 Japanese breast cancer patients who qualified for breast-conserving radiotherapy. Using the National Cancer Institute-Common Toxicity Criteria scoring system, version 2, the patients were grouped according to EASRs, defined as those occurring within 3 months of starting radiotherapy (Grade 1 or less, n = 290; Grade 2 or greater, n = 109). A total of 999 single nucleotide polymorphisms from 137 candidate genes for radiation susceptibility were genotyped, and the haplotype associations between groups were assessed.

RESULTS

The global haplotype association analysis (p < 0.05 and false discovery rate < 0.05) indicated that estimated haplotypes in six loci were associated with EASR risk. A comparison of the risk haplotype with the most frequent haplotype in each locus showed haplotype GGTT in CD44 (odds ratio [OR] = 2.17; 95% confidence interval [CI], 1.07-4.43) resulted in a significantly greater EASR risk. Five haplotypes, CG in MAD2L2 (OR = 0.55; 95% CI, 0.35-0.87), GTTG in PTTG1 (OR = 0.48; 95% CI, 0.24-0.96), TCC (OR = 0.48; 95% CI, 0.26-0.89) and CCG (OR = 0.50; 95% CI, 0.27-0.92) in RAD9A, and GCT in LIG3 (OR = 0.46; 95% CI, 0.22-0.93) were associated with a reduced EASR risk. No significant risk haplotype was observed in REV3L.

CONCLUSION

Individual radiosensitivity can be partly determined by these haplotypes in multiple loci. Our findings may lead to a better understanding of the mechanisms underlying the genetic variation in radiation sensitivity and resistance among breast cancer patients.

Mutation of the p16/CDKN2 gene and loss of heterozygosity in malignant mucosal melanoma and adenoid cystic carcinoma of the head and neck

The purpose of this study was to investigate the molecular biological characteristics of malignant mucosal melanoma (MMM) and adenoid cystic carcinoma (ACC) of the head and neck. We analyzed the common genetic abnormalities that may help to identify the loci in the genes involved in the development of MMM and ACC of the head and neck by PCR-LOH on chromosomes 1p, 6q, 9p, 10q, 11q, 12q, 17p, and 19q. LOH was observed in 6 of 12 cases of MMM and in 12 of 15 cases of ACC informative for at least one of the loci analyzed. One distinct deleted region was identified at chromosome 9p21. In addition, to identify a possible involvement of p16/CDKN2 PCR-SSCP and auto-DNA sequence analysis were also performed to detect any mutation of the p16/CDKN2. Particularly, 2 missense mutations were detected in codon 225 and 226, both in MMM and ACC. There were mutational hot spots in the p16/CDKN2 gene. These results suggested that mutation of the p16/CDKN2 gene was a common factor in the development of human MMMs and ACCs, while this gene may be correlated with development and/or progression of a subtype and play a role in the oncogenesis of these cancers.

Carbon ion radiotherapy for stage I non-small cell lung cancer using a regimen of four fractions during 1 week

BACKGROUND

A phase I/II study was first conducted for the treatment of stage I non-small cell lung cancer (NSCLC) from 1994 to 1999 to determine the optimal dose. On the basis on the results, a phase II study using a regimen of four fractions during 1 week was performed. The purpose of the present study was to determine the local control and 5-year survival rates.

METHODS

From December 2000 to November 2003, 79 patients with 80 primary lesions were treated. Using a fixed dose of 52.8 GyE for stage IA NSCLC and 60.0 GyE for stage IB NSCLC in four fractions during 1 week, the primary tumors were irradiated with carbon beams alone. The average age of the patients was 74.8 years. Sixty-two (78.5%) of these patients were medically inoperable. Local control and survival were determined using the Kaplan-Meier method. The data were statistically processed using the log-rank test.

RESULTS

All patients were observed for a minimum of 3 years or until death, with a median follow-up time of 38.6 months, ranging from 2.5 to 72.2 months. The local control rate for all patients was 90% (T1: 98%, T2: 80%). The patients' 5-year lung cancer-specific survival rate was 68% (IA: 87%, IB: 42%). The overall survival was 45% (IA: 62%, IB: 25%). Half of the deaths were attributable to intercurrent diseases. No toxic reactions in the lung greater than grade 3 were detected.

CONCLUSION

Carbon ion beam radiotherapy with a regimen of four fractions during 1 week has been proven as a valid alternative to surgery for stage I NSCLC and to offer particular benefits, especially for elderly and inoperable patients.

LOH analysis of free DNA in the plasma of patients with mucosal malignant melanoma in the head and neck

BACKGROUND

We have conducted charged-particle radiotherapy for mucosal malignant melanoma (MMM) in the head and neck, using carbon ion beams. However, even with the use of carbon ion radiotherapy that is characterized by high local tumor control, a significant number of patients develop metastases after therapy. We conducted research on the assumption that, in MMM, the detection of loss of heterozygosity (LOH) from free DNA in the circulating plasma may be of practical use in the diagnosis of recurrence and metastasis.

METHODS

We took blood samples prior to therapy from 17 patients with MMM in the head and neck, and extracted free DNA in plasma. Four types of microsatellite markers were used for LOH detection.

RESULTS

LOH was detected in 1 of 5 patients (20%) for D1S243, 2 of 5 patients (40%) for D6S311, 11 of 17 patients (65%) for D9S161, and 1 of 6 patients (17%) for D19S246.

CONCLUSION

Evidence based on the irradiated tumor volume suggested a tendency for the group of patients found to have LOH in two loci to have a larger mean tumor volume than the patient groups with no detectable LOH or with LOH detectable in only one locus. Of the 17 patients in this study 4 patients had recurrence and/or metastasis, and all 4 of these patients were found to have LOH in at least one or more loci for any region. LOH analysis of free DNA in plasma may be useful for the early diagnosis of MMM.

Clinical Results of Carbon Ion Radiotherapy at NIRS

In 1994 a Phase I/II clinical study on carbon ion radiotherapy was begun at NIRS using HIMAC, which was then the world's only heavy ion accelerator complex dedicated to medical use in a hospital environment. Among several types of ion species, we have chosen carbon ions for cancer therapy because they had the most optimal properties in terms of possessing, both physically and biologically, the most effective dose-localization in the body. The purpose of the clinical study was to investigate the efficacy of carbon ion radiotherapy against a variety of tumors as well as to develop effective techniques for delivering an efficient dose to the tumor. The RBE of carbon ions was estimated to be 2.0 to 3.0 along the SOBP for acute skin reactions. As of August 2006, a total of 2,867 patients had been entered into Phase I/II or Phase II studies and analyzed for toxicity and local tumor response. The results have shown that carbon ion radiotherapy has the potential ability to provide a sufficient dose to the tumor with acceptable morbidity in the surrounding normal tissues. Tumors that appear to respond favorably to carbon ions include locally advanced tumors and those with histologically non-squamous cell type of tumors such as adenocarcinoma, adenoid cystic carcinoma, malignant melanoma, hepatoma, and bone/soft tissue sarcoma. By taking advantage of the biological and physical properties of high-LET radiation, the efficacy of treatment regimens with small fractions in short treatment times has been confirmed for almost all types of tumors in carbon ion radiotherapy.

[Comparison of treatment planning by carbon ion radiotherapy and by intensity-modulated radiotherapy for prostatic adenocarcinoma]

OBJECTIVE

To evaluate the potential benefit of carbon ion radiotherapy (C-ion RT) through comparison with photon intensity-modulated radiotherapy (IMRT) in dose distribution for prostatic adenocarcinoma.

METHODS

In randomly selected 5 patients, treatment planning of C-ion RT (4 coplanar beams) and IMRT (7 coplanar fields) were worked out by computer working station. In order to make a meaningful comparison, it was defined that the 95% isodose surface had to cover 100% of the PTV in each plan; all dose was given as normalized dose with the definition of the minimum dose of the PTV being equal to 95% of prescribed dose. Dose-volume histograms (DVHs) of the tumor and organ-at-risks (OARs) were calculated. Volume irradiated more than or equal to some specified doses, conformity index ( CI) , and inhomogeneity coefficient (IC) of each treatment plan was compared, respectively.

RESULTS

With C-ion RT, the mean irradiated volumes (in %) of the rectum were significantly smaller than that with IMRT except for 95% dose level, and C-ion RT could provide complete protection to the posterior rectal wall. In addition, C-ion RT could also remarkably reduce the dose to the bladder, femoral heads and non-target normal tissues at each dose level. Dose conformation and homogeneity in the target volume of C-ion RT were better than that in IMRT (mean CI50%, 3.36 vs. 5.04, mean CI95%, 1.20 vs. 1.46, mean IC, 0.03 vs. 0.12).

CONCLUSION

Compared with IMRT, C-ion RT can obtain better dose distribution, and may reduce tumor recurrence and radiation-induced complications in prostatic adenocarcinoma.

Analysis of non-genetic risk factors for adverse skin reactions to radiotherapy among 284 Breast Cancer patients

OBJECTIVES

We analyzed non-genetic risk factors for adverse skin reactions to irradiation at 4 collaborating Japanese institutions, to design future investigation into genetic risk factors for adverse skin reactions to irradiation in a multicenter setting.

METHODS

From April 2001, 284 breast cancer patients, who underwent radiotherapy with breast-conserving surgery, were enrolled from 4 collaborating institutions in Japan. We graded skin reactions according to international scoring systems. Clinical factors were tested against adverse effects.

RESULTS

Grade 1+ skin reactions were observed in 261 (92%) of the patients in less than 3 months, 118 (42%) at 3 months, and 29 (10%) at 6 months in the late phase. Univariate analysis of treatment risk factors (such as the use of a multi-leaf colimeter, wedge-filter, or immobilization device) for skin reactions revealed a significant association (p< 0.0001). After a variable selection procedure with logistic regression, the institution, operative procedure, and magnitude of photon energy remained significantly associated with acute skin reactions. Only the institution was an explanatory variable for skin reactions at 3 and 6 months in the final logistic model.

CONCLUSION

After stratification, substantial remaining variations in the occurrence of skin reactions of a given level suggested that individual genetic factors contribute markedly to individual radiosensitivity. Analysis of genetic factors associated with adverse effects would be possible by stratifying patients according to institution. Selection of eligible institutions, where appropriate treatment modalities could be performed, would also be possible when planning such a study.

Outcomes of visual acuity in carbon ion radiotherapy: Analysis of dose–volume histograms and prognostic factors

PURPOSE

To analyze the tolerance dose for retention of visual acuity in patients with head-and-neck tumors treated with carbon ion radiotherapy.

METHODS AND MATERIALS

From June 1994 to March 2000, 163 patients with tumors in the head and neck or skull base region were treated with carbon ion radiotherapy. Analysis was performed on 54 optic nerves (ONs) corresponding to 30 patients whose ONs had been included in the irradiated volume. These patients showed no evidence of visual impairment due to other factors and had a follow-up period of >4 years. All patients had been informed of the possibility of visual impairment before treatment. We evaluated the dose-complication probability and the prognostic factors for the retention of visual acuity in carbon ion radiotherapy, using dose-volume histograms and multivariate analysis.

RESULTS

The median age of 30 patients (14 men, 16 women) was 57.2 years. Median prescribed total dose was 56.0 gray equivalents (GyE) at 3.0-4.0 GyE per fraction per day (range, 48-64 GyE; 16-18 fractions; 4-6 weeks). Of 54 ONs that were analyzed, 35 had been irradiated with <57 GyE (maximum dose [Dmax]) resulting in no visual loss. Conversely, 11 of the 19 ONs (58%) irradiated with >57 GyE (Dmax) suffered a decrease of visual acuity. In all of these cases, the ONs had been involved in the tumor before carbon ion radiotherapy. In the multivariate analysis, a dose of 20% of the volume of the ON (D20) was significantly associated with visual loss.

CONCLUSIONS

The occurrence of visual loss seems to be correlated with a delivery of >60 GyE to 20% of the volume of the ON.

Examination of GyE system for HIMAC carbon therapy

PURPOSE

A retrospective analysis was made to examine appropriateness in the estimation of the biologic effectiveness of carbon-ion radiotherapy using resultant data from clinical trials at the heavy-ion medical accelerator complex (HIMAC) at the National Institute of Radiological Sciences in Chiba, Japan.

METHODS AND MATERIALS

At HIMAC, relative biologic effectiveness (RBE) values of therapeutic carbon beams were determined based on experimental results of cell responses, on values expected with the linear-quadratic model, and based on experiences with neutron therapy. We use fixed RBE values independent of dose levels, although this apparently contradicts radiobiologic observations. Our RBE system depends only on LET of the heavy-ion radiation fields. With this RBE system, over 2,000 patients have been treated by carbon beams. With data from these patients, the local control rate of non-small-cell lung cancer was analyzed to verify the clinical RBE of the carbon beam. The local control rate was compared with rates published by groups from Gunma University and Massachusetts General Hospital. Using a simplified tumor control probability (TCP) model, clinical RBE values were obtained for different levels of TCP.

RESULTS

For the 50% level of the clinical TCP, the RBE values nearly coincide with those for in vitro human salivary gland cell survival at 10%. For the higher levels of clinical TCP, the RBE values approach closer to those adapted in clinical trials at HIMAC.

Detection of Tumor DNA in Plasma Using Whole Genome Amplification

Altered microsatellite DNA in the blood of cancer patients may provide a novel means for tumor detection. Such alterations are a major characteristic of many types of tumor especially those associated with head or neck cancer. Moreover, recent evidence suggests that senescent tumor cells release DNA into the circulation, which is subsequently carried by the blood and thus enriched in the serum and plasma. We tested 10 head and neck cancer patients (5 with malignant melanomas (MM) and 5 with adenoid cystic carcinomas (ACC)) by polymerase chain reaction (PCR)-based microsatellite analysis of DNA from white blood cells and paired plasma samples. Our goal was to amplify two microsatellite markers, D1S243 and D19S246, which sometimes show microsatellite alterations in head and neck cancer patients. However amplification of fragments from three loci in the plasma samples proved impossible, probably due to the small amounts of DNA isolated. We used multiple displacement amplification (MDA) to amplify genomic DNA from the plasma samples. Two microsatellite fragments were amplified from whole genome amplified DNA. Among 5 heterozygote samples, 3 showed the same pattern in DNA samples from both blood cells and plasma but 2 showed loss of heterozygosity (LOH). Although further study is necessary to confirm whether the LOH found in this study reflects alteration in circulating tumor cell DNA, application of whole genome amplification may allow DNA analysis from limited amounts of such DNA and provide a minimally invasive diagnostic procedure and useful aid in therapy.

DNA repair capacity measured by high throughput alkaline comet assays in EBV-transformed cell lines and peripheral blood cells from cancer patients and healthy volunteers

We collected peripheral blood (PB) from 556 patients with various types of cancer who had undergone radiotherapy and from 81 healthy volunteers. We exposed whole PB and Epstein-Barr virus-transformed lymphoblastoid cell lines (EBLs) derived from the PB mononucleocytes to X-irradiation (5 Gy). Using the alkaline comet assay, we measured the immediate DNA damage and, at 15 min, the % residual damage. In PB, the immediate damage was similar in patients and healthy volunteers while the % residual damage (mean+/-S.D.) was significantly higher in patients with breast (54.3+/-A23.9), cervical (54.7+/-A23.9), head/neck (56.8+/-A24.4), lung (60.1+/-23.5), or esophageal cancers (59.5+/-A33.7) than in healthy donors (42.9+/-19.6) (P<0.05). We did not observe such differences in the EBV-transformed cell lines. Thus, radiation sensitivity of fresh PB cells measured by the alkaline comet assay was related to cancer status.

Two cases of orbital adenocarcinoma treated with heavy charged carbon particle irradiation

BACKGROUND

Orbital adenocarcinoma is a relatively rare, primary orbital malignant epithelial tumor, and shares the poor prognosis of orbital adenoid cystic carcinoma. We report the cases of two patients with orbital adenocarcinoma who were treated with heavy charged carbon particle irradiation and followed up for more 6 years.

METHOD

Two patients with orbital adenocarcinoma, 62 and 74 years old, received 57.6 GyE of heavy charged particle irradiation therapy.

RESULTS

In both cases, the size of the tumor gradually decreased after carbon ion irradiation therapy. No recurrences or metastasis of the tumor were found for more than 6 years.

CONCLUSION

Orbital adenocarcinoma has a poor prognosis in general. Two patients with orbital adenocarcinoma were treated with heavy charged carbon particle irradiation therapy and had a relatively good outcome and good prognosis. We believe that heavy charged carbon particle irradiation therapy is a promising therapy for orbital adenoid cystic carcinoma and adenocarcinoma.

Carbon ion radiotherapy for unresectable sacral chordomas

PURPOSE

The purpose is to evaluate the efficacy and toxicity of carbon ion radiotherapy for unresectable sacral chordomas.

EXPERIMENTAL DESIGN

We performed a retrospective analysis of 30 patients with unresectable sacral chordomas treated with carbon ion radiotherapy at the Heavy Ion Medical Accelerator in Chiba, Japan. Twenty-three patients presented with no prior treatment, and the remaining 7 patients had locally recurrent disease following previous surgical resection. The median clinical target volume was 546 cm(3). The applied carbon ion dose ranged from 52.8 to 73.6 GyE (gray equivalent, median 70.4) in 16 fixed fractions over 4 weeks.

RESULTS

At median follow-up of 30 months (range, 9 to 87 months), 26 patients were still alive and 24 patients remained continuously disease-free. Overall and cause-specific survival rates at 5 years were 52 and 94%, respectively. The overall local control rate at 5 years was 96%. Two patients experienced severe skin/soft tissue complications requiring skin grafts. No other treatment-related surgical interventions, including colostomy or urinary diversion, were carried out. All patients have remained ambulatory and able to stay at home after carbon ion radiotherapy.

CONCLUSIONS

Carbon ion radiotherapy is effective and safe in the management of patients with unresectable sacral chordomas and offers a promising alternative to surgery.

MR Imaging of Brain Injury Induced by Carbon Ion Radiotherapy for Head and Neck Tumors

To clarify the characteristics of magnetic resonance (MR) imaging of radiation-induced brain injury following carbon ion radiotherapy and to observe the changes in lesions over time, we evaluated 40 patients with radiation-induced brain injury from carbon ion radiotherapy for head and neck tumors. Their primary lesions received a radiation dose of 48 to 70.4 Gray equivalent (GyE) in 16 to 18 fractions. MR imaging of radiation-induced brain injury was graded as follows: Grade 1: change in focal white matter; focal contrast enhancement and surrounding edema; Grade 2: nonenhanced area or cystic lesion in enhanced lesion; Grade 3: focal necrosis with mass effect; and Grade 4: mass effect requiring surgical intervention. Radiation-induced brain injury appeared as early as 2 months and as late as 57 months after carbon ion therapy (mean interval, 22.2 months). MR findings of initial lesion were Grade 1 in 26 cases (65.0%), Grade 2 in 13 (32.5%), and Grade 3 in 1 (2.5%). Brain injury was always found in the radiation field initially, but cystic lesion and edema later extended outside the field in 10 cases (25.0%). In follow-up MR studies, size of edema or enhanced lesion was reduced in 17 patients (42.5%) without treatment. Two cases with large cystic lesions required surgery. Improvement of radiation-induced brain injury was observed more often than had been previously described. Because edema and cystic lesion can occasionally extend outside the radiation field, such findings do not exclude the possibility of radiation-induced brain injury. Careful observation is recommended because cystic lesions can enlarge enough to require surgical treatment in some cases.

Results of the first prospective study of carbon ion radiotherapy for hepatocellular carcinoma with liver cirrhosis

PURPOSE

To evaluate the toxicity and antitumor effect of carbon ion radiotherapy for hepatocellular carcinoma within a Phase I-II trial.

METHODS AND MATERIALS

Between June 1995 and February 1997, 24 patients with histopathologically proven hepatocellular carcinoma were treated to 15 fractions within 5 weeks in a step-wise dose-escalation study. The disease stage was Stage II in 10, IIIA in 6, and IVA in 8 patients. The Common Toxicity Criteria, Radiation Therapy Oncology Group/European Organization for the Research and Treatment of Cancer criteria, and Child-Pugh score were used to evaluate toxicity. The antitumor effect was evaluated by the tumor response, cumulative local control, and survival rates.

RESULTS

During a median follow-up of 71 months (range, 63-83 months), no severe adverse effects and no treatment-related deaths occurred. The Child-Pugh score did not increase by >2 points after the start of therapy. In 78% and 75% of all patients, the score did not increase by >1 point in the early and late phase, respectively. The overall tumor response rate was 71%. The local control and overall survival rate was 92% and 92%, 81% and 50%, and 81% and 25% at 1, 3, and 5 years, respectively.

CONCLUSION

Carbon ion radiotherapy appears safe and effective for patients with hepatocellular carcinoma. Additional clinical studies using a larger subject group are required to confirm the therapeutic efficacy.

Primary sebaceous carcinoma of the lacrimal gland treated by carbon ion radiotherapy

Sebaceous carcinoma is a rare primary neoplasm of the lacrimal gland and, to the best of our knowledge, only six cases have been reported previously. Sebaceous carcinoma of the orbit more commonly occurs as secondary invasion from the eyelid, but may occur by way of metastatic spread from elsewhere in the body. We describe a patient who presented with a rapidly growing neoplasm of the lacrimal gland which, histologically, was a sebaceous carcinoma. The eyelid was entirely normal on examination. In this patient we found a single tumor cell line within the normal lacrimal gland. In this article we describe the diagnosis and treatment with carbon ion radiotherapy of primary sebaceous carcinoma of the lacrimal gland, a condition not previously reported in Japan.

Carbon ion radiotherapy for stage I non-small cell lung cancer

BACKGROUND AND PURPOSE

Heavy ion radiotherapy is a promising modality because of its excellent dose localization and high biological effect on tumors. Using carbon beams, a dose escalation study was conducted for the treatment of stage I non-small cell lung cancer (NSCLC) to determine the optimal dose.

MATERIALS AND METHODS

The first stage phase I/II trial using 18 fractions over 6 weeks for 47 patients and the second one using nine fractions over 3 weeks for 34 patients were conducted by the dose escalation method from 59.4 to 95.4 Gray equivalents (GyE) in incremental steps of 10% and from 68.4 to 79.2 GyE in 5% increments, respectively. The local control and survival rates were obtained using the Kaplan-Meier method.

RESULTS

Radiation pneumonitis at grade III occurred in three of 81 patients, but they fully recovered. This was not a dose-limiting factor. The local control rates in the first and second trials were 64% and 84%, respectively. The total recurrence rate in both trials was 23.2%. The infield local recurrence in the first trial was significantly dependent on carbon dose. The doses greater than 86.4 GyE at 18 fractions and 72 GyE at nine fractions achieved a local control of 90% and 95%, respectively. The 5 year overall and cause-specific survivals in 81 patients were 42% and 60%, respectively.

CONCLUSIONS

With our dose escalation study, the optimum safety and efficacy dose of carbon beams was determined. Carbon beam therapy attained almost the same results as surgery for stage I NSCLC although this was a I/II study.

Allelic loss of chromosome 2 in human oral squamous cell carcinoma: correlation with lymph node metastasis

To evaluate the role of chromosome 2 deletions in human oral squamous cell carcinoma (SCC) progression and to define the precise location of putative tumor suppressor genes, we examined 40 primary tumors and seven lymph node metastatic tumors from 40 patients with oral SCC by the polymerase chain reaction (PCR)-loss of heterozygosity (LOH) assay, using 10 different polymorphic loci on the long arm of chromosome 2. LOH was observed in 67.5% of the patients at one or more loci on the chromosome 2q. Two commonly deleted regions with high frequency of LOH, D2S1327 region at 2q32-35 (31.6%) and D2S206 region at 2q36 (36.7%), were identified by the deletion mapping of chromosome 2q, suggesting the presence of putative tumor suppressor genes associated with oral SCC. Examination of seven metastatic tumors also revealed four commonly deleted regions, D2S436, D2S1327, D2S155, and D2S164. Of these four regions D2S1327 region has no significant increase in the frequency of LOH between in primary tumors and in metastatic tumors. However, at other three regions the frequencies were much increased in metastatic tumors, comparing the results in primary tumors. Especially, very high frequencies of LOH in metastatic tumors were detected at two regions on 2q35, 100.0% at D2S155 and 57.1% at D2S164, suggesting the significant relationship between lymph node metastasis and LOH at these two regions. Our results indicate that LOH on chromosome 2q is a common event in oncogenesis and/or progression of oral SCC, and also suggest that the LOH at 2q35 play a significant role in the lymph node metastasis.

Efficacy and safety of carbon ion radiotherapy in bone and soft tissue sarcomas

PURPOSE

To evaluate the tolerance for and effectiveness of carbon ion radiotherapy in patients with unresectable bone and soft tissue sarcomas.

PATIENTS AND METHODS

We conducted a phase I/II dose escalation study of carbon ion radiotherapy. Fifty-seven patients with 64 sites of bone and soft tissue sarcomas not suited for resection received carbon ion radiotherapy. Tumors involved the spine or paraspinous soft tissues in 19 patients, pelvis in 32 patients, and extremities in six patients. The total dose ranged from 52.8 to 73.6 gray equivalent (GyE) and was administered in 16 fixed fractions over 4 weeks (3.3 to 4.6 GyE/fraction). The median tumor size was 559 cm(3) (range, 20 to 2,290 cm(3)). The minimum follow-up was 18 months.

RESULTS

Seven of 17 patients treated with the highest total dose of 73.6 GyE experienced Radiation Therapy Oncology Group grade 3 acute skin reactions. Dose escalation was then halted at this level. No other severe acute reactions (grade > 3) were observed in this series. The overall local control rates were 88% and 73% at 1 year and 3 years of follow-up, respectively. The median survival time was 31 months (range, 2 to 60 months), and the 1- and 3-year overall survival rates were 82% and 46%, respectively.

CONCLUSION

Carbon ion radiotherapy seems to be a safe and effective modality in the management of bone and soft tissue sarcomas not eligible for surgical resection, providing good local control and offering a survival advantage without unacceptable morbidity.

A horizontal CT system dedicated to heavy-ion beam treatment

A horizontal helical CT system to be used for 3-D treatment planning and for positioning verification of patients in seated position was installed in the treatment room with a fixed horizontal heavy-ion beam line. The system achieved the expected mechanical consistency and reliability.

High-dose-rate intracavitary irradiation using linear source arrangement for stage II and III squamous cell carcinoma of the uterine cervix

PURPOSE

The purpose of this article is to evaluate fractionated high-dose-rate (HDR) intracavitary irradiation using linear source arrangement (LSA) for patients with squamous cell carcinoma of the uterine cervix.

MATERIALS AND METHODS

The subjects consisted of 217 patients (71 patients with stage II and 146 with stage III disease) who received external beam therapy (EBT) followed by fractionated HDR intracavitary irradiation using LSA between January 1980 and June 1990. In EBT, 40 Gy in 20 fractions (40 Gy/20 Fr) or 39.6 Gy/22 Fr was delivered to the whole pelvis and an additional 10 Gy/5 Fr or 10.8 Gy/6 Fr was delivered to the parametrium. The intracavitary irradiation dose was 30 Gy/6 Fr or 35 Gy/7 Fr with a daily fraction size of 5 Gy and two fractions per week. During the intracavitary treatment, most patients were treated on an out-patient basis.

RESULTS

Cause-specific 5-year survival rates were 77% for stage II and 50% for stage III. Pelvic failure rates were 13% for stage II and 36% for stage III. In multivariate analyses, improved cause-specific survival was significantly associated with stage II (P = 0.0003), higher pretreatment serum hemoglobin level (P = 0.0015), higher pretreatment serum total protein level (P = 0.0029), and shorter total treatment time (P = 0.0024). The rate of severe (grade 3 or 4) late complication was 2% for the rectum, 1% for the small intestine or sigmoid colon and 1% for the bladder.

CONCLUSIONS

Fractionated HDR intracavitary irradiation using LSA is an effective treatment for patients with uterine cervical cancer without need for hospitalization.

Fast neutron therapy for malignant gliomas--results from NIRS study. National Institute of Radiological Sciences

The results of combined radiotherapy with fast neutrons and photons for 39 malignant gliomas were analyzed. The patients consisted of 16 astrocytoma grade 3 and 23 glioblastoma multiforme. There were two kinds of combination methods which were either "boost therapy" or "mixed beam therapy" with a localized fast neutron field. The average dose of fast neutrons was 569 cGy (n, gamma) and that of photons was 36.86 Gy. The median survival of astrocytoma grade 3 was 15.5 months, and that of glioblastoma multiforme was also 15.5 months. With respect to the combination methods, there was no difference between the boost regimen and the mixed beam regimen. This result seems to have no impact on survival compared to other reports. Patients' ages, surgical debulking procedures, and photon doses were listed as significant prognostic factors, but doses of fast neutrons had no prognostic significance for survival. Because there were no moderate or severe complications for the brain except permanent epilation in all cases, neutron dose escalation study with a localized field will be recommended.