Takuro Ariga

Phase II Trial of Radiotherapy After Hyperbaric Oxygenation With Multiagent Chemotherapy (Procarbazine, Nimustine, and Vincristine) for High-Grade Gliomas: Long-Term Results

PURPOSE To analyze the long-term results of a Phase II trial of radiotherapy given immediately after hyperbaric oxygenation (HBO) with multiagent chemotherapy in adults with high-grade gliomas. METHODS AND MATERIALS Patients with histologically confirmed high-grade gliomas were administered radiotherapy in daily 2 Gy fractions for 5 consecutive days per week up to a total dose of 60 Gy. Each fraction was administered immediately after HBO, with the time interval from completion of decompression to start of irradiation being less than 15 minutes. Chemotherapy consisting of procarbazine, nimustine, and vincristine and was administered during and after radiotherapy. RESULTS A total of 57 patients (39 patients with glioblastoma and 18 patients with Grade 3 gliomas) were enrolled from 2000 to 2006, and the median follow-up of 12 surviving patients was 62.0 months (range, 43.2-119.1 months). All 57 patients were able to complete a total radiotherapy dose of 60 Gy immediately after HBO with one course of concurrent chemotherapy. The median overall survival times in all 57 patients, 39 patients with glioblastoma and 18 patients with Grade 3 gliomas, were 20.2 months, 17.2 months, and 113.4 months, respectively. On multivariate analysis, histologic grade alone was a significant prognostic factor for overall survival (p < 0.001). During treatments, no patients had neutropenic fever or intracranial hemorrhage, and no serious nonhematologic or late toxicities were seen in any of the 57 patients. CONCLUSIONS Radiotherapy delivered immediately after HBO with multiagent chemotherapy was safe, with virtually no late toxicities, and seemed to be effective in patients with high-grade gliomas.

External beam boost irradiation for clinically positive pelvic nodes in patients with uterine cervical cancer

The purpose of this study was to retrospectively analyze the treatment results of boost external beam radiotherapy (EBRT) to clinically positive pelvic nodes in patients with uterine cervical cancer. The study population comprised 174 patients with FIGO stages 1B1–4A cervical cancer who were treated with definitive radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT). Patients with positive para-aortic or common iliac nodes (≥10 mm in the shortest diameter, as evaluated by CT/MRI) were ineligible for the study. Fifty-seven patients (33%) had clinically positive pelvic nodes. The median maximum diameter of the nodes was 15 mm (range, 10–60 mm) and the median number of positive lymph nodes was two (range, one to four). Fifty-two of 57 patients (91%) with positive nodes were treated with boost EBRT (6–10 Gy in three to five fractions). The median prescribed dose of EBRT for nodes was 56 Gy. The median follow-up time for all patients was 66 months (range, 3–142 months). The 5-year overall survival rate, disease-free survival rate and pelvic control rate for patients with positive and negative nodes were 73% and 92% (P = 0.001), 58% and 84% (P < 0.001), and 83% and 92% (P = 0.082), respectively. Five of 57 node-positive patients (9%) developed pelvic node recurrences. All five patients with nodal failure had concomitant cervical failure and/or distant metastases. No significant difference was observed with respect to the incidence or severity of late complications by application of boost EBRT. The current retrospective study demonstrated that boost EBRT to positive pelvic nodes achieves favorable nodal control without increasing late complications.

Treatment outcomes of patients with FIGO Stage I/II uterine cervical cancer treated with definitive radiotherapy: a multi-institutional retrospective research study

The purpose of this study was to analyze the patterns of care and outcomes of patients with FIGO Stage I/II cervical cancer who underwent definitive radiotherapy (RT) at multiple Japanese institutions. The Japanese Radiation Oncology Study Group (JROSG) performed a questionnaire-based survey of their cervical cancer patients who were treated with definitive RT between January 2000 and December 2005. A total of 667 patients were entered in this study. Although half of the patients were considered suitable for definitive RT based on the clinical features of the tumor, about one-third of the patients were prescribed RT instead of surgery because of poor medical status. The RT schedule most frequently utilized was whole-pelvic field irradiation (WP) of 30 Gy/15 fractions followed by WP with midline block of 20 Gy/10 fractions, and high-dose-rate intracavitary brachytherapy (HDR-ICBT) of 24 Gy/4 fractions prescribed at point A. Chemotherapy was administered to 306 patients (46%). The most frequent regimen contained cisplatin (CDDP). The median follow-up time for all patients was 65 months (range, 2–135 months). The 5-year overall survival (OS), pelvic control (PC) and disease-free survival (DFS) rates for all patients were 78%, 90% and 69%, respectively. Tumor diameter and nodal status were significant prognostic indicators for OS, PC and DFS. Chemotherapy has potential for improving the OS and DFS of patients with bulky tumors, but not for non-bulky tumors. This study found that definitive RT for patients with Stage I/II cervical cancer achieved good survival outcomes.

Predictive factors of uterine movement during definitive radiotherapy for cervical cancer

Abstract To determine the predictive factors affecting uterine movement during radiotherapy (RT), we quantified interfraction uterine movement using computed tomography (CT) and cone-beam CT (CBCT). A total of 38 patients who underwent definitive RT for cervical cancer were retrospectively analyzed. We compared pre-RT planning CT (n = 38) and intratreatment CBCT (n = 315), measuring cervical and corporal movement in each direction. Correlations between uterine movement and volume changes of the bladder and rectum on all CBCT scans were analyzed using Spearman rank correlation analysis. Relationships between the mean uterine movement and patient factors were analyzed using the Mann–Whitney test. The mean corpus movement was: superior margin (cranio–caudal direction), 7.6 ± 5.9 mm; anterior margin (anteroposterior direction), 8.3 ± 6.3 mm; left margin (lateral direction), 3.3 ± 2.9 mm; and right margin (lateral direction), 3.0 ± 2.3 mm. Generally, the mean values for cervical movement were smaller than those for the corpus. There was a significant, weak correlation between changes in bladder volume and the movement of the superior margin of the corpus (ρ = 0.364, P < 0.001). There was a significant difference in movement of the superior margin of the corpus between the subgroups with and without a history of previous pelvic surgery (P = 0.007). In conclusion, change in bladder volume and a history of previous surgery were significantly related to intrafractional corpus movement; however, our observations suggest that the accurate prediction of uterine movement remains challenging.

Computed tomography–based image-guided brachytherapy for cervical cancer: correlations between dose–volume parameters and clinical outcomes

Abstract This study evaluated the oncologic outcomes and complications of cervical cancer patients in terms of CT-based image-guided brachytherapy (IGBT) parameters. Of 68 cervical cancer patients treated with definitive radiotherapy/concurrent chemoradiotherapy, most received whole-pelvis external beam RT (EBRT) of 40 Gy in 20 fractions, pelvic EBRT with central shield of 10 Gy in 5 fractions, and CT-based IGBT of 18 Gy in 3 fractions prescribed to point A. Cumulative EBRT and IGBT doses were calculated as the total equivalent dose in 2 Gy fractions (EQD2). The median follow-up was 31 (3–52) months. The 2-year overall survival, local control, pelvic control, and disease-free survival rates of the 68 patients were 92%, 83%, 82% and 73%, respectively. The HR-CTV D90, length from the tandem axis to left/right margin of the HR-CTV (T-LR), and HR-CTV volume were significant IGBT parameters for predicting local/pelvic control. Patients who received an HR-CTV D90 of >60 Gy, compared with ≤60 Gy, had significantly better local/pelvic control. Furthermore, 70 Gy was a marginally significant HR-CTV D90 cut-off affecting local control. T-LR was an independent IGBT parameter predicting local/pelvic control on multivariate analysis. Three patients developed Grade 3 or higher treatment-related complications. The D2cm3 of organs at risk were not significant predictors of complications. Future challenges for further improving outcomes include additional interstitial needles for irregularly shaped HR-CTVs, and moderate dose escalation, especially for patients with poor tumor responses.

Proposed definition of the vaginal cuff and paracolpium clinical target volume in postoperative uterine cervical cancer.

PURPOSE The aim of this study was to develop an appropriate definition for vaginal cuff and paracolpium clinical target volume (CTV) for postoperative intensity modulated radiation therapy in patients with uterine cervical cancer. METHODS AND MATERIALS A working subgroup was organized within the Radiation Therapy Study Group of the Japan Clinical Oncology Group to develop a definition for the postoperative vaginal cuff and paracolpium CTV in December 2013. The group consisted of 5 radiation oncologists who specialized in gynecologic oncology and a gynecologic oncologist. A comprehensive literature review that included anatomy, surgery, and imaging fields was performed and was followed by multiple discreet face-to-face discussions and e-mail messages before a final consensus was reached. RESULTS Definitions for the landmark structures in all directions that demarcate the vaginal cuff and paracolpium CTV were decided by consensus agreement of the working group. A table was created that showed boundary structures of the vaginal cuff and paracolpium CTV in each direction. CONCLUSIONS A definition of the postoperative cervical cancer vaginal cuff and paracolpium CTV was developed. It is expected that this definition guideline will serve as a template for future radiation therapy clinical trial protocols, especially protocols involving intensity modulated radiation therapy.

Appropriate radiation dose for symptomatic relief and local control in patients with adult T cell leukemia/lymphoma

Abstract Adult T-cell leukemia/lymphoma (ATL) is an aggressive peripheral T-cell neoplasm that occurs only in patients with human T-cell leukemia virus type 1. No large study or randomized trial investigating radiotherapy (RT) for ATL has been performed. We retrospectively reviewed 55 courses of RT for 41 consecutive patients with ATL who underwent RT between 2000 and 2016 at our institutions. The results showed that RT for local ATL lesions can achieve symptomatic improvement in 92% of cases. Local remission, either complete remission (CR) or partial response (PR), was achieved in 100% of the patients (CR: 89%, PR: 11%) with ≥40 Gy irradiation. CR or PR was achieved in 71% (CR: 29%, PR: 43%) with 30–39 Gy and in 73% (CR: 6.7%, PR: 67%) with ≤29 Gy irradiation. The mean total radiation dose in the CR and PR groups differed significantly (38 vs 25 Gy, P = 0.0002). The maximum acute toxicity was Grade 0–2 in all patients, except for one patient experienced Grade 3 radiation dermatitis. In-field relapses occurred in 36% of patients, and the frequency of in-field relapses was 11%, 30% and 71% among those who achieved CR, PR and SD, respectively. All 9 patients who received total skin irradiation experienced cutaneous relapses, with a median of 63 days (range, 7–210 days). Almost all (39 of 41) patients with ATL experienced out-of-field progression after RT. In conclusion, RT was confirmed to be effective and safe for palliative treatment of local ATL lesions.

Concurrent weekly cisplatin versus triweekly cisplatin with radiotherapy for locally advanced squamous-cell carcinoma of the cervix: a retrospective analysis from a single institution

Objective: To compare patients with cervical cancer who were primarily treated with concurrent chemoradiotherapy (CCRT) using 20 mg m−2 CDDP for 5 days every 3 weeks with weekly regimens of 40 mg m−2. Methods: We retrospectively analyzed 185 patients with Stage IB–IVA squamous-cell carcinoma of the cervix who were treated with CCRT between 2005 and 2013 at our hospital. The CCRT regimen consisted of cisplatin (CDDP) at 20 mg m−2 for 5 days every 3 weeks or 40 mg m−2 weekly, administered concomitantly with RT. Results: The median age was 50 years (range: 22–70 years) in the triweekly group and was 50.5 years (range: 28–70 years) in the weekly group. The 5-year overall survival rate in the triweekly and weekly groups were 82.0% and 83.3%, respectively (p = 0.851); their disease-free survival rate was 79.6% and 78.1%, respectively (p = 0.672). In the triweekly group, 56 patients (50.9%) had grade 3/4 leukopenia, which was significantly higher than that of 11 patients (15%) in the weekly group (p < 0.0001). Conclusion: The weekly CDDP regimen for CCRT seems better in patients with International Federation of Gynecology and Obstetrics Stages IB–IVA squamous-cell carcinoma of the cervix. Advances in knowledge: The weekly CDDP regimen for CCRT seems better in patients with International Federation of Gynecology and Obstetrics Stages IB–IVA squamous-cell carcinoma of the cervix.

SU-E-T-123: Dosimetric Comparison Between Portrait and Landscape Orientations in Radiochromic Film Dosimetry

PURPOSE To compare the dosimetric properties of radiochromic films with different orientation. METHODS A sheet of EBT3 film was cut into eight pieces with the following sizes: 15×15 cm2 (one piece), 5×15 cm2 (two) and 4×5 cm2 (five). A set of two EBT3 sheets was used at each dose level. Two sets were used changing the delivered doses (1 and 2 Gy). The 5×15 cm2 pieces were rotated by 90 degrees in relation to each other, such that one had landscape orientation and the other had portrait orientation. All 5×15 cm2 pieces were irradiated with their long side aligned with the x-axis of the radiation field. The 15×15 cm2 pieces were irradiated rotated at 90 degrees to each other. Five pieces, (a total of ten from two sheets) were used to obtain a calibration curve. The irradiated films were scanned using an Epson ES-2200 scanner and were analyzed using ImageJ software. In this study, no correction was applied for the nonuniform scanner signal that is evident in the direction of the scanner lamp. Each film piece was scanned both in portrait and landscape orientations. Dosimetric comparisons of the beam profiles were made in terms of the film orientations (portrait and landscape) and scanner bed directions (perpendicular and parallel to the scanner movement). RESULTS In general, portrait orientation exhibited higher noise than landscape and was adversely affected to a great extent by the nonuniformity in the direction of the scanner lamp. A significant difference in the measured field widths between the perpendicular and parallel directions was found for both oientations. CONCLUSION Without correction for the nonuniform scanner signal in the direction of the scanner lamp, a landscape orientation is preferable. A more detailed investigation is planned to evaluate quantitatively the effect of orientation on the dosimetric properties of a film.

SU-E-T-698: Fractal Analysis for Assessing IMRT Modulation Complexity

Purpose: To evaluate the feasibility of fractal dimension (FD as a modulation complexity metric in intensity modulated radiation therapy (IMRT) treatment fields. Methods: Uniform sliding window (SW) deliveries changing the leaf gap width (1–50 mm) were utilized for this study. During the SW deliver, the dynamic treatment log file (Dynalog file) was acquired. Binary images were produced from the DynaLog files of the sliding window fields. For each sliding window field, five binary images changing the pixel size (0.1, 0.2, 0.3, 0.4 and 0.5 mm) were produced. The FD was evaluated by the Box‐Counting method. The box sizes were 1, 2, 4, 8, 16 and 32 pixels. The fractal dimension for each segment and the overall field was evaluated by the averaging five images. In this study, FD is the average for all segments and the standard deviation of FD is the variation of FD between segments. The analysis was carried out by in‐house programming in ImageJ (http://imagej.nih.gov/ij/ ). A highly modulated field may Result in small leaf gaps, therefore low FD is expected for increased modulation complexity. Results: The FD decreases with the decrease of leaf gap width. The FDs and SDs were 1.964±0.0007, 1.879±0.0054, 1.816±0.0092, 1.402±0.0429 for 50, 10, 5, and 1 mm gap, respectively.The large SDs for small gap widths resulted from variability in leaf positions during the SW delivery. For 1 mm gap, a low FD value of 1.35 was observed at the middle segment where uneven leaf position could be observed visually. Conclusion: The FD for smaller leaf gap which implies highly modulated was lower. This work indicates that the FD method could be used for assessing IMRT plan complexity. Further studies such as comparison to other metrics and its usefulness in clinical IMRT plans are needed.