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Needle applicator displacement/Corrective action/High-dose-rate interstitial brachytherapy/Recurrent uterine cancer. We investigated daily needle applicator displacement during multifractionated high-dose-rate interstitial brachytherapy (HDR-ISBT) for postoperative recurrent uterine cancer. Eight patients with postoperative recurrent uterine cancer received HDR-ISBT with or without external beam radiotherapy using our un ique ambulatory technique. To analyze displacement, we obtained daily computed tomography (CT) images for 122 flexible needle applicators at 21, 45, 69, and 93 hours after implantation. Displacement was defined as the length between the center of gravity of titanium markers and the needle applicator tips along the daily CT axis. For cases in which displacement was not corrected, we also calculated the dose that covered 90% of the clinical target volume (D90(CTV)) using a dose–volume histogram (DVH). Median caudal needle applicator displacement at 21, 45, 69, and 93 hours was 3, 2, 4, and 5 mm, respectively. More than 15 mm displacement was observed f or 2% (2 of 122) and 17% (10 of 60) of needle applicators at 21 and 93 hours, respectively. Cases in which dwell positions were not changed to correct the treatment plan, 2 of 8 patients showed more than 10% reduction in D90(CTV) values compared with the initial treatment plan. Correction of dwell positions of the treatment source improves treatment DVH for multifractionated HDR-ISBT.

Background: To investigate the treatment results of intracranial meningiomas treated with hypofractionated stereotactic radiation therapy in three to five fractions. Methods: Thirty-one patients (32 lesions) with intracranial meningioma were treated with hypofractionated stereotactic radiation therapy in three to five fractions using CyberKnife. Fifteen lesions were diagnosed as Grade I (World Health Organization classification) by surgical resection and 17 lesions were diagnosed as meningioma based on radiological findings. The median follow-up time was 48 months. The median planning target volume was 6.3 cm 3 (range, 1.4‐27.1), and the prescribed dose (D90� ) ranged from 21 to 36 Gy (median, 27.8) administrated in three to five fractions. Results: Five-year overall and progression-free survival rate of all 31 patients with intracranial meningioma was 86 and 83%, respectively. Five-year progression-free rate of all 32 lesions was 87%. Six of the 31 patients (19%) developed marked peritumoral edema, three of whom were asymptomatic and three symptomatic, the latter with late adverse effects of more than or equal to Grade 3. The mean planning target volume of the six lesions with marked peritumoral edema was 15.6 cm 3 , and for the remaining 26 lesions without marked peritumoral edema was 7.1 cm 3 (P ¼ 0.004). The threshold diameter of 2.56 cm for meningioma was calculated from the planning target volume (11 cm 3 ) and was used as marker of developing peritumoral edema (P ¼ 0.003). Conclusions: Tumor volume is a significant indicative factor for peritumoral edema in intracranial meningioma treated with hypofractionated stereotactic radiation therapy in three to five factions.

Background To assess inter-observer variability in delineating target volume and organs at risk in benign tumor adjacent to optic tract as a quality assurance exercise. Methods We quantitatively analyzed 21 plans made by 11 clinicians in seven CyberKnife centers. The clinicians were provided with a raw data set (pituitary adenoma and meningioma) including clinical information, and were asked to delineate the lesions and create a treatment plan. Their contouring and plans (10 adenoma and 11 meningioma plans), were then compared. In addition, we estimated the influence of differences in contouring by superimposing the respective contours onto a default plan. Results The median planning target volume (PTV) and the ratio of the largest to the smallest contoured volume were 9.22 cm3 (range, 7.17 - 14.3 cm3) and 1.99 for pituitary adenoma, and 6.86 cm3 (range 6.05 - 14.6 cm3) and 2.41 for meningioma. PTV volume was 10.1 ± 1.74 cm3 for group 1 with a margin of 1 -2 mm around the CTV (n = 3) and 9.28 ± 1.8 cm3(p = 0.51) for group 2 with no margin (n = 7) in pituitary adenoma. In meningioma, group 1 showed larger PTV volume (10.1 ± 3.26 cm3) than group 2 (6.91 ± 0.7 cm3, p = 0.03). All submitted plan keep the irradiated dose to optic tract within the range of 50 Gy (equivalent total doses in 2 Gy fractionation). However, contours superimposed onto the dose distribution of the default plan indicated that an excessive dose 23.64 Gy (up to 268% of the default plan) in pituitary adenoma and 24.84 Gy (131% of the default plan) in meningioma to the optic nerve in the contours from different contouring. Conclusion Quality assurance revealed inter-observer variability in contour delineation and their influences on planning for pituitary adenoma and meningioma near optic tract.

Background To examine the role of brachytherapy for aged patients 80 or more in the trend of rapidly increasing number. Methods We examined the outcomes for elderly patients with node negative oral tongue cancer (T1-3N0M0) treated with brachytherapy. The 21 patients (2 T1, 14 T2, and 5 T3 cases) ranged in age from 80 to 89 years (median 81), and their cancer was pathologically confirmed. All patients underwent definitive radiation therapy, with low dose rate (LDR) Ra-226 brachytherapy (n = 4; median 70Gy), with Ir-192 (n = 12; 70Gy), with Au-198 (n = 1) or with high dose rate (HDR) Ir-192 brachytherapy (n = 4; 60 Gy). Eight patients also underwent external radiotherapy (median 30 Gy). The period of observation ranged from 13 months to 14 years (median 2.5 years). We selected 226 population matched younger counterpart from our medical chart. Results Definitive radiation therapy was completed for all 21 patients (100%), and acute grade 2-3 mucositis related to the therapy was tolerable. Local control (initial complete response) was attained in 19 of 21 patients (90%). The 2-year and 5-year local control rates were 91%, (100% for T1, 83% for T2 and 80% for T3 tumors after 2 years). These figures was not inferior to that of younger counterpart (82% at 5-year, n.s.). The cause-specific survival rate was 83% and the regional control rate 84% at the 2-years follow-up. However, 12 patients died because of intercurrent diseases or senility, resulting in overall survival rates of 55% at 2 years and 34% at 5 years. Conclusion Age is not a limiting factor for brachytherapy for appropriately selected elderly patients, and brachytherapy achieved good local control with acceptable morbidity.

Purpose To objectively evaluate the radiation dermatitis caused by accelerated partial breast irradiation (APBI) using high-dose-rate interstitial brachytherapy. Patients and Methods The skin color and moisture changes were examined using a newly installed spectrophotometer and corneometer in 22 patients who had undergone APBI using open cavity implant high-dose-rate interstitial brachytherapy (36 Gy in six fractions) and compared with the corresponding values for 44 patients in an external beam radiotherapy (EBRT) control group (50–60 Gy in 25–30 fractions within 5–6 weeks) after breast conserving surgery. Results All values changed significantly as a result of APBI. The extent of elevation in a∗ (reddish) and reduction in L∗ (black) values caused by APBI were similar to those for EBRT, with slightly delayed recovery for 6–12 months after treatment owing to the surgical procedure. In contrast, only APBI caused a change in the b∗ values, and EBRT did not, demonstrating that the reduction in b∗ values (yellowish) depends largely on the surgical procedure. The changes in moisture were less severe after APBI than after EBRT, and the recovery was more rapid. The toxicity assessment using the Common Toxicity Criteria, version 3, showed that all dermatitis caused by APBI was Grade 2 or less. Conclusion An objective analysis can quantify the effects of APBI procedures on color and moisture cosmesis. The radiation dermatitis caused by APBI using the present schedule showed an equivalent effect on skin color and a less severe effect on moisture than the effects caused by standard EBRT.

To evaluate radiation dermatitis objectively in patients with breast cancer who had undergone post-operative radiotherapy after breast-conserving surgery. Skin color (L*, a*, and b* values) and moisture analyses were performed for both breasts (before, after, 1 month, 6 months, and 1 year after radiotherapy) to examine irradiated and non-irradiated skin divided into four quadrants in 118 patients. These patients underwent breast conservative surgery followed by 50 Gy/25 fractions (median) of radiotherapy with or without boost irradiation (10 Gy/5 fractions). L*, a*, and moisture values were changed by irradiation and maximized at completion or 1 month after radiotherapy. One year after radiotherapy, the skin color had returned to the range observed prior to radiotherapy. However, moisture did not return to previous values even 1 year after treatment. The lateral upper side (quadrant C) showed greater changes than other quadrants in the L* value (darker) at the end of radiotherapy. The Common Toxicity Criteria version 3 scores were found to correlate well with a* and L* values at the completion and 1 month after radiotherapy. Boost radiotherapy intensified reddish and darker color changes at the completion of radiotherapy, while chemotherapy did not intensify the skin reaction caused by radiotherapy. Moisture impairment as a result of irradiation lasts longer than color alterations. Objective assessments are useful for analyzing radiation dermatitis.

The aim of this study was to assess radiation dermatitis, especially exploring the influence of neoadjuvant systemic therapy (NST). We examined maximum toxicity using the Common Toxicity Criteria version 3 score (CTC v3) following radiotherapy between 40 patients treated with NST and 59 patients without NST. In addition, objective skin color (L*, a*, b* values) and moisture analyses were applied in 13 NST and 25 control patients, and the ratio of the values for the irradiated side to the nonirradiated side was calculated. For the CTC v3 assessment, 27 grade 1 (68%) and 13 grade 2 (32%) reactions occurred in the NST group and 44 grade 1 (75%) and 15 grade 2 (25%) reactions in the control group. All ratios except the b* ratio showed significant alterations when radiotherapy was added. The ratio of the a* value peaked at the completion of radiotherapy, whereas the L* ratio bottomed out 1 month later. Furthermore, moisture change remained even 1 year after treatment. Boost irradiation doses caused enhanced alterations in the L* and a* ratios. Furthermore, the L* and a* ratios had good agreement with the CTC v3 assessment. NST did not enhance alterations. Objective analysis is useful for detailed assessment of radiation dermatitis. NST did not worsen skin reactions.

Purpose To investigate the feasibility of our novel image-based high-dose-rate interstitial brachytherapy (HDR-ISBT) for uterine cervical cancer, we evaluated the dose–volume histogram (DVH) according to the recommendations of the Gynecological GEC-ESTRO Working Group for image-based intracavitary brachytherapy (ICBT). Methods and Materials Between June 2005 and June 2007, 18 previously untreated cervical cancer patients were enrolled. We implanted magnetic resonance imaging (MRI)-available plastic applicators by our unique ambulatory technique. Total treatment doses were 30–36 Gy (6 Gy per fraction) combined with external beam radiotherapy (EBRT). Treatment plans were created based on planning computed tomography with MRI as a reference. DVHs of the high-risk clinical target volume (HR CTV), intermediate-risk CTV (IR CTV), and the bladder and rectum were calculated. Dose values were biologically normalized to equivalent doses in 2-Gy fractions (EQD2). Results The median D90 (HR CTV) and D90 (IR CTV) per fraction were 6.8 Gy (range, 5.5–7.5) and 5.4 Gy (range, 4.2–6.3), respectively. The median V100 (HR CTV) and V100 (IR CTV) were 98.4% (range, 83–100) and 81.8% (range, 64–93.8), respectively. When the dose of EBRT was added, the median D90 and D100 of HR CTV were 80.6 Gy (range, 65.5–96.6) and 62.4 Gy (range, 49–83.2). The D2cc of the bladder was 62 Gy (range, 51.4–89) and of the rectum was 65.9 Gy (range, 48.9–76). Conclusions Although the targets were advanced and difficult to treat effectively by ICBT, MRI-aided image-based ISBT showed favorable results for CTV and organs at risk compared with previously reported image-based ICBT results.

Purpose The purpose of this study was to reconfirm our previous findings that the rectal dose and source strength both affect late rectal bleeding after high-dose-rate intracavitary brachytherapy (HDR-ICBT), by using a rectal dose calculated in accordance with the definitions of the International Commission on Radiation Units and Measurements Report 38 (ICRU RP ) or of dose–volume histogram (DVH) parameters by the Groupe Europeen de Curietherapie of the European Society for Therapeutic Radiology and Oncology. Methods and Materials Sixty-two patients who underwent HDR-ICBT and were followed up for 1 year or more were studied. The rectal dose for ICBT was calculated by using the ICRP RP based on orthogonal radiographs or the DVH parameters based on computed tomography (CT). The total dose was calculated as the biologically equivalent dose expressed in 2-Gy fractions (EQD 2 ). The relationship between averaged source strength or the EQD 2 and late rectal bleeding was then analyzed. Results When patients were divided into four groups according to rectal EQD 2 (≥ or 2 .h -1 ), the group with both a high EQD 2 and a high source strength showed a significantly greater probability of rectal bleeding for ICRU RP , D 2cc , and D 1cc . The patients with a median rectal dose above the threshold level did not show a greater frequency of rectal bleeding unless the source strength exceeded 2.4 cGy.m 2 .h -1 . Conclusions Our results obtained with data based on ICRU RP and CT-based DVH parameters indicate that rectal dose and source strength both affect rectal bleeding after HDR-ICBT.

To establish an initial database of external-beam radiotherapy (EBRT) for clinically localized prostate cancer used in Osaka, Japan, and, by analyzing the results of the Osaka multicenter cooperative study, to determine time trends, outcome, and applicability of existing and the authors’ original risk stratification methods. Data of 652 patients with clinically localized prostate cancer (T1–4 N0 M0) were accrued from July to December 2007. These patients had been treated from 1995 through 2006 with consecutive definitive EBRT of ≥ 60 Gy at eleven institutions, mainly in Osaka. Altogether, 436 patients were eligible for analysis using several risk stratification methods, namely, those of D’Amico et al., the National Comprehensive Cancer Network (NCCN), and Seattle, as well as the authors’ original Prostate Cancer Risk Index (PRIX). The number of patients showed a tenfold increase over 10 years, together with a rapid spread of the use of Gleason Score from 0% to > 90% of cases. The dominant RT dose fractionation was 70 Gy/35 fractions (87%). Hormone therapy had been administered to 95% of the patients and the higher PRIX corresponded to the higher rate of hormone usage. 3- and 5-year biochemical relapse-free survival (bRFS) rates were 85% and 70%, respectively. The D’Amico (p = 0.132), NCCN (p = 0.138), Seattle (p = 0.041) and PRIX (p = 0.044) classifications showed weak or no correlation with bRFS, while the own modified three-class PRIX (PRIX 0, 1–5, 6) showed a strong correlation (p = 0.002). The use of prostate EBRT in Japan is still in its infancy, but is rapidly expanding. The short-term outcomes have been satisfactory considering the moderate RT dose. A very high rate of hormone usage may affect the outcome favorably, but also may compromise the usefulness of current risk stratification.

Purpose The aim of the study was to evaluate the results of high-dose-rate interstitial brachytherapy (HDR-ISBT) for patients with advanced cervical carcinoma in which intracavitary radiation therapy may result in a suboptimal dose distribution. Methods and Materials Between 1995 and 2005, 25 patients of median age 64 years were treated with external beam radiation therapy and HDR-ISBT. The International Federation of Gynecology and Obstetrics stages of the patients were I (4%), II (16%), III (68%), and IVA (12%). Whole pelvic irradiation of 30 Gy/15 fractions was followed by HDR-ISBT of 30 Gy/5 fractions/3 days. Subsequently, additional pelvic external beam radiation therapy of 20 Gy/10 fractions was delivered with a midline block. The median followup period was 55 months. Results The actuarial 5-year progression-free survival and overall survival rates for all cases were 42% and 54%, respectively. For the 17 patients with a Stage III tumor, the 5-year local control and overall survival rates were 73% and 51%, respectively. Two patients (8%) developed late toxicities of Grade 3. Conclusions A high rate of pelvic control and survival with acceptable level of late toxicities were obtained for patients with advanced cervical carcinoma treated with HDR-ISBT.

To investigate the feasibility of accelerated partial breast irradiation (APBI) for Japanese patients, we started high-dose-rate interstitial brachytherapy (HDR-ISBT) as monotherapy after breast-conserving surgery (BCS). We implanted 45 Tis-2 breast cancer patients at National Hospital Organization Osaka National Hospital between June 2002 and June 2006. Our eligibility criteria were broader than the ones used previously in western countries. We included margin-positive cases and younger patients (median age: 44; range: 26–68) to adapt the criteria for Japanese women. Total prescribed doses were 36–42 Gy in six to seven fractions, and the volumes encompassed by 100% prescribed dose (V100) were 38.5–315.1 cc. Fifteen patients received chemotherapy. Treatment could be completed for all patients. Two local failures (4%) and two distant metastases were observed, while one patient died of liver metastasis. Seven wound complications, four with and three without infection, and two rib fractures occurred. The significant risk factors for wound complications were non-administration of prophylactic antibiotics during ISBT (P

This retrospective study analyzed the effect of the activity of high-dose-rate (HDR) (192)Ir source on late rectal bleeding after HDR intracavitary radiotherapy (ICRT) in patients with uterine cervix cancer.One hundred thirty-two patients who underwent HDR-ICRT and external beam radiotherapy (EBRT) were analyzed. The rectal point dose in ICRT was calculated by inserting a lead wire into the rectal lumen and summed with the whole-pelvic EBRT dose. The rectal biologic effective dose (BED) was calculated. The relationship between averaged source activity or the BED and late rectal bleeding were analyzed.Three-year actuarial rectal bleeding probabilities were 46% (or =100 Gy(3)) and 18% (or = 100 Gy(3)), respectively (p0.005). When patients were divided into four groups according to rectal BED (or = oror =100 Gy(3)) and source activity (or = oror =2.4 cGy.m(2).h(-1)), the group with both a high BED and high activity showed significantly greater probability (58% at 3 years; p0.005). It was noted that the probability of the group with BED of 100 Gy(3) or greater was high, but that was not the case with 2.4 cGy.m(2).h(-1) or less.This is the first clinical report concerning the source activity effect of HDR (192)Ir on late rectal bleeding in patients undergoing HDR-ICRT. This suggests that when source activity is higher than 2.4 cGy.m(2).h(-1), ICRT should be performed with more caution not to exceed 100 Gy(3) in total.

Objective To assess actual rates of late vaginal stenosis and identify predisposing factors for complications among patients with previously untreated cervical cancer following high-dose-rate brachytherapy. Methods We performed longitudinal analyses of 57 patients using the modified Dische score at 6, 12, 18, 24, 36, and 60 months after treatment, which consisted of 15 interstitial brachytherapys and 42 conventional intracavitary brachytherapys, with a median follow-up time of 36 months (range, 6 to 144 months). Results More than half of the patients developed grade 1 (mild) vaginal stenosis within the first year of follow-up, and grade 2 (97.5%, moderate) to grade 3 (severe) stenosis gradually increased with time. Actual stenosis rates for grade 1, 2, and 3 were 97.5% (95% confidence interval [CI], 92.7 to 97.5), 60.7% (95% CI, 42.2 to 79.3), and 7.4% (95% CI, 0 to 18.4) at 3 years after treatment. Pallor reaction grade 2-3 at 6 months was only a statistically significant predisposing factor for grade 2-3 late vaginal stenosis 3 years or later with a hazard ratio of 3.48 (95% CI, 1.32 to 9.19; p=0.018) by a multivariate Cox proportional hazard model. Patients with grade 0-1 pallor reaction at 6 months showed a grade ≥2 vaginal stenosis rate of 53%, whereas the grade 2-3 pallor reaction group achieved a grade ≥2 vaginal stenosis rate at 3 years at 100% (p=0.001). Conclusion High-dose-rate brachytherapy was associated with high incidence of late vaginal stenosis. Pallor reaction grade 2-3 at 6 months was predictive of late grade 2-3 vaginal stenosis at 3 years after treatment. These findings should prove helpful for patient counseling and preventive intervention.

Background To examine the background characteristics of elderly patients (65 years or older) with node-negative mobile tongue cancer (T1-2N0M0) who showed worse local control than a younger group. Materials and methods We retrospectively analyzed background data for 265 patients treated with brachytherapy with or without external radiotherapy between 1967 and 1999. We examined dental factors (such as irritation by prosthesis), leukoplakia, tobacco smoking and alcohol consumption for comparisons between the elderly (age ≥65 years; n = 83) and a control group (64 years or younger; n = 182). Results The elderly patients showed a worse outcome than the control group (respectively 86% and 70% at 5 years; P Conclusions Age and dental factors (including prosthesis irritation) are potentially important prognostic factors for local control of oral tongue cancer treated with brachytherapy, especially for elderly patients.