Multi-institutional analysis of early glottic cancer from 2000 to 2005.

BACKGROUND: The purpose of this study is to analyze the outcome of patients with early glottic cancer (GC) treated with radiotherapy (RT) with or without chemotherapy at 10 institutions in the Tokai District, Japan. METHODS: Ten institutions combined data from 279 patients with T1-T2 GC treated with RT with or without chemotherapy between 2000 and 2005. The overall survival rate, disease-specific survival rate, and local control rate were evaluated in 270 patients, except for incomplete cases due to issues such as discontinuation, using the method of Kaplan-Meier and compared using the log-rank test. Results were considered statistically significant at the level of p < 0.05. RESULTS: For 122 patients, the tumors were classified as T1a, while 64 patients had T1b tumors, and 84 patients had T2 tumors. In three cases of T1 tumors, the subtype was unknown. Combined chemoradiotherapy (CRT) was administered during each stage, and various chemotherapy drugs and regimens were used. The median follow-up period was 55.4 months. The 5-year LC rates for T1a, Tb, and T2 tumors in all patients were 87.9%, 82.7%, and 74.1%, respectively. The difference between T1a and T2 was statistically significant (p = 0.016). The 5-year LC rates for T1a, Tb, and T2 with CRT were 92.7%, 78.6%, and 80.7%, respectively, while the rates with radiation alone were 86.5%, 83.8%, and 64.4%, respectively. The difference between CRT and RT alone was not statistically significant in each stage. CONCLUSIONS: In this survey, CRT was performed for early GC at most institutions in clinical practice. Our data showed no statistical difference in the LC rates between CRT and RT alone in each stage. However, there was a tendency for the LCRs of the CRT group to be more favorable than those of the RT group in the T2-stage.

Dosimetric evaluation of whole breast radiotherapy using field-in-field technique in early-stage breast cancer.

BACKGROUND: The purpose of this study is to evaluate the dosimetric benefits of whole breast radiotherapy (WBRT) using the field-in-field technique compared with conventional tangential field radiotherapy with physical wedges for WBRT. METHODS: In this planning study, 20 patients were included. For each patient, two different treatment plans were created for the entire treated breast. The dosimetric parameters of the planning target volume for dose evaluation and the organs at risk for each planning technique were compared. In the clinical outcome, acute skin toxicity for each treatment technique was compared. RESULTS: The field-in-field technique significantly reduced the maximum dose, the volumes receiving >107% of the prescription dose, and homogeneity index for the planning target volume for dose evaluation compared with the tangential field technique. For each dosimetry of the organs at risk, excluding the contralateral breast, the field-in-field technique significantly reduced the maximum dose and the volumes receiving >10, 30, and 50 Gy of the prescribed dose. The volume receiving <1 Gy of the prescription dose for the contralateral breast was significantly decreased using the field-in-field technique. In addition, the dose distribution using the field-in-field technique in the target volume was less sensitive to the effects of breast motion during normal breathing. In the clinical outcome, the field-in-field technique significantly reduced Radiation Therapy Oncology Group (RTOG) grade II acute skin toxicity compared with the tangential field technique (3.1 vs. 10.6%). CONCLUSIONS: WBRT using the field-in-field technique improved dose distribution in the treated breast and decreased RTOG grade II acute skin toxicity compared with conventional tangential field radiotherapy with physical wedges.

Combined chemoradiotherapy for early glottic cancer in clinical practice in Japan: analysis of 10 institutions.

AIM: To conduct a retrospective analysis regarding treatment strategies for early glottic cancer (GC) at ten institutions. PATIENTS AND METHODS: A questionnaire-based survey was used to obtain personal and medical information on patients who started radiation therapy for T1 or T2 GC between January 2000 and December 2005. RESULTS: A total of 279 patients were registered for the survey, of whom 124 patients were classified as T1a, with 65 patients as T1b and 87 patients as T2. The rates of chemoradiotherapy for T1a, T1b and T2 were 24%, 23% and 60%, respectively. A comparison of results for academic and non-academic hospitals showed statistically different rates of combination therapy for T1a (6.9% vs. 39.3%, respectively; p<0.001) and T1b (11.4% vs. 36.6%, respectively; p<0.05) but not for T2 (70.0% vs. 54.4%, respectively; p = 0.158). CONCLUSION: In clinical practice, combined chemoradiotherapy was performed for early GC at most institutions in Tokai District, Japan.

Rectal dose reduction using three-dimensional conformal radiotherapy for locally advanced prostate cancer: A combination of conformal dynamic-arc and five-static field technique.

BACKGROUND AND PURPOSE: The aims of this study are to compare our three-dimensional conformal radiotherapy (3D-CRT) plan using a combination of conformal dynamic-arc and five-static field (DASF) technique with other 3D-CRT plans for prostate cancer, and to estimate whether dose escalation is possible with DASF radiotherapy (DASF-RT). METHODS AND MATERIALS: Twenty patients with prostate cancer were included in this study. For each patient, five different treatment plans including DASF-RT were created to entire prostate and seminal vesicles. Dose distribution and rectal dose-volume histogram (DVH) for each planning technique were compared. RESULTS: In DASF-RT treatment plan, rectum V40, V50, V60, and V70 were 61.6%, 39.6%, 21.4%, and 0.6%, respectively. Compared with four 3D-CRT techniques, DASF-RT technique significantly reduce rectum V50 to V70 without increasing irradiated bladder and femoral head volumes. In addition, in the simulation of dose escalation to 76Gy, the increase of each rectal dose-volume parameter (V40 to V75) was small enough. However, in dose escalation to 78Gy, rectum V75 exceeded 5%. CONCLUSION: DASF-RT technique could significantly reduce rectal volumes receiving 50-70Gy compared with other 3D-CRT techniques. DASF-RT was safe and feasible for dose escalation to 76Gy in prostate radiotherapy.

Long-term clinical outcomes of postoperative pelvic radiotherapy with or without prophylactic paraaortic irradiation for stage I-II cervical carcinoma with positive lymph nodes: retrospective analysis of predictive variables regarding survival and failure patterns.

We performed retrospective analysis to classify the risk hazard of patients with stage I-II cervical cancer with lymph node metastases treated with postoperative radiotherapy. From 1981 to 1995, 106 patients with early stage cervical carcinoma who received adjuvant pelvic radiation were entered in the analysis. The median patient age was 53.0 years (range 21-73). The median dose of 45.3 Gy (range, 32.1-56.4 Gy) was delivered over the whole pelvis. Seventy patients also received prophylactic paraaortic radiation (median 44 Gy; range 22-46 Gy). The 5/10-year overall survival (OAS), disease-free survival (DFS), pelvic control, and distant metastasis-free survival rates were 69.1/63.5%, 62.4/58.1%, 85.7/84.3%, and 74.1/71.6%, respectively. In the uni-/multivariate analyses, the significant prognostic factors of OAS and DFS proved to be disease stage, duration period between operation and radiotherapy, histology, and presence or absence of common iliac lymph node metastasis. Using the results of these analyses, we devised a predictive model for DFS. In this model, the 5-year DFS rates of patients with low (N = 35), intermediate (N = 59), and high-risk factors (N = 12) were 88.1%, 56.7%, and 16.7%, respectively (p < 0.0001). The majority of analyzed patients did not have adequate DFS estimates in this series. High-risk patients should receive a more intensive strategy, such as concurrent chemoradiotherapy. On the other hand, the effort to reduce toxicity should be considered carefully.

Retrospective analysis of postoperative radiotherapy for node-negative cervical carcinoma with stage IB-IIB disease.

BACKGROUND: We performed retrospective analysis to evaluate the outcomes of postoperative radiotherapy for patients with cervical carcinoma without lymph node metastasis. METHODS: From 1981 to 1995, 68 stage I-II cervical carcinoma patients without nodal disease who received adjuvant pelvic radiotherapy were entered into the present analysis. Criteria for postoperative radiotherapy were (1) deep stromal invasion (> or = 1/2; n = 63), (2) positive parametrial invasion (n = 38) and (3) close or positive surgical margin (n = 21). The median patient age was 54.0 years (range, 29-69 years). The median dose of 45.3 Gy (range, 43.4-56.4 Gy) was delivered over the whole pelvis median 21.0 days (range 12-68 days) after surgery. RESULTS: The 5/10-year overall survival, disease-free survival, pelvic control and distant metastasis-free survival rates were 89.7/85.7, 85.3/83.2, 95.5/95.5 and 90.7/90.7%, respectively. Histology of adenocarcinoma (n = 4), large tumor size and prolonged period between operation and radiotherapy were significantly adverse prognostic factors of overall and disease-free survival by univariate analysis. The risk score referred from the GOG report correlated well with disease-free survival (P = 0.018), but showed only a tendency for overall survival as a prognostic factor (P = 0.07). Overall treatment time proved to be a significant variable for overall survival (P = 0.02), but not for disease-free survival (P = 0.056). Both risk score and overall treatment time proved to be significant prognostic factors in the multivariate model. Major adverse effects occurred in three patients (4.4%) without mortality. CONCLUSIONS: In this analysis, clinical outcome from adjuvant postoperative radiotherapy was thought to be feasible with both satisfactory pelvic control and acceptable lower toxicity.

Clinical assessment by MRI for patients with stage II cervical carcinoma treated by radiation alone in multicenter analysis: are all patients with stage II disease suitable candidates for chemoradiotherapy?

PURPOSE: From recent randomized trials, patients with Stage II cervical carcinoma are thought to be candidates for chemoradiotherapy. To refine the strategy for Stage II patients, we performed a retrospective multi-institutional analysis using MRI. METHODS AND MATERIALS: From three institutions, 84 patients with Stage II cancer diagnosed by MRI were entered into the study. All patients received intracavitary brachytherapy with (n = 83) or without (n = 1) external beam radiotherapy. Uni- and multivariate analyses were performed to identify the prognostic factors for overall survival (OAS), disease-free survival (DFS), pelvic control (PC), and distant metastasis-free survival (DMFS). RESULTS: The 5-year DFS rate of patients with maximal tumor size (D(max)) > or =50 mm (46.2%) was significantly lower than that for patients with D(max) <50 mm (88.0%; p <0.0001). Large size or volume and lymph node swelling were also significant prognostic factors of OAS, DFS, PC, and DMFS. In the multivariate model, size or volume was a significant prognostic factor of OAS, DFS, PC, and DMFS, and lymph node swelling was a prognostic factor for DFS, PC, and DMFS. Using these two prognostic factors, patients were divided into 3 subgroups. The 5-year DFS rate of patients with risk 0 (D(max) <50 mm and negative lymph node swelling), 1 (D(max) > or =50 mm or positive lymph node swelling), and 2 (D(max) > or =50 mm and positive lymph nodes) was 93.2%, 53.3%, and 25.0%, respectively (p <0.0001). CONCLUSION: In this stage-limiting analysis, we clarified the stratification according to clinical risk with the aid of MRI. For patients with low-risk factors, especially for elderly patients, radiation alone would probability be a feasible option. In the future, a randomized trial using criteria with MRI would help to identify the optimal strategy for patients with Stage II disease.