Masayuki Kagemoto

Optimum fractionation for high-dose-rate endoesophageal brachytherapy following external irradiation of early stage esophageal cancer

PURPOSE To establish the optimum fractionation for high-dose-rate (HDR) endoesophageal brachytherapy (EBT) for early stage esophageal cancer from retrospective data of patients treated with different HDR schedules following external beam irradiation (EBI). METHODS AND MATERIALS The study population consisted of 35 consecutive early stage esophageal cancer patients who received EBI to the mediastinum, plus EBT, between May 1992 and November 1995 at the Hiroshima University Medical Center and Hiroshima City Hospital. All patients were treated with EBI, with doses ranging from 50 to 61 Gy. The spinal cord was spared after 44-45 Gy. HDR EBT was performed using a double-balloon applicator in conjunction with an Ir-192 remote afterloading system. One group of 10 patients was given a weekly endoesophageal boost of 4 or 5 Gy at a distance of 5 mm from the applicator surface over a period of 1-2 weeks. Another group of 25 patients was treated with 4 or 5 endoesophageal boosts with a fraction dose of either 2.5 or 2 Gy for 1 week. The linear quadratic (LQ) formula was used to calculate the biologically effective dose (BED) for tumor (Gy10) and esophageal mucosa (Gy3); Gy10 means alpha/beta equals 10 Gy, and Gy3 means alpha/beta equals 3 Gy. The Kaplan-Meier method was used to calculate the local control and late complication rates, while the Cox-Mantel test was used to evaluate statistical significance (p < 0.01). RESULTS Nine (26%) of the 35 patients recurred locally and 7 (20%) had late complications (esophageal ulcer grade by RTOG/EORTC criteria > 1). The 5-year overall survival, local control, and late complication rates were 38%, 57%, and 26%, respectively. The probability of local recurrence was not affected by the treatment parameters. Results from the LQ formula significantly correlate with data on late complications. A BED > 134 Gy3 and a fraction number = < 3 were associated with late complications (grade > 1). BED analysis showed that the fractionation dose should be decreased to 2.5 or 2.0 Gy at a distance of 5 mm from the applicator surface, and the number of doses increased to 4 or 5, respectively, to yield a satisfactory BED (< 134 Gy3). CONCLUSION A significant reduction in endoesophageal brachytherapy dose per fraction is necessary to reduce late complications. Our current treatment protocol for early-stage esophageal cancer consists of EBI of 60 Gy followed by 4 EBT doses at a fraction dose of 2.5 Gy applied over 1 week.

Radiation therapy for nasopharyngeal carcinoma. Retrospective review of 105 patients based on a survey of Kansai Cancer Therapist Group

One hundred five patients with nasopharyngeal carcinoma were treated with radiation therapy combined with or without chemotherapy at 16 of the participating institutes in Kansai Cancer Therapist Group, Japan, from January 1978 to December 1980. The study comprised 77 males and 28 females; their ages ranged from 15 to 80 years (mean, 53 years). Five‐year survival rates according to stage were as follows: Stage I, 100%; Stage II, 67%; Stage III, 44%; and Stage IV, 34%. As far as Stage IV disease was concerned, the radiation therapy only group showed significantly poorer prognosis than the combined radiation and chemotherapy group (P < 0.05). Cancer 57:2267–2271, 1986.

Clinical results of external beam radiotherapy alone with a concomitant boost program or with conventional fractionation for cervical cancer patients who did not receive intracavitary brachytherapy

A combination of external beam radiotherapy (EBRT) and intracavitary brachytherapy (ICBT) is well established as the standard radical radiotherapy (RT) for cervical cancer. However, it is sometimes necessary to perform EBRT alone for patients where ICBT is not feasible. For these patients, we initiated EBRT alone with three-dimensional conformal radiotherapy (3DCRT). The purpose of this study is to evaluate the results of EBRT alone without ICBT for patients with cervical cancer. Sixteen patients were treated with EBRT alone between 2002 and 2009. There were three stage IIB, six stage IIIB and seven patients with stage IVA disease. A total of 10 patients were treated with a median dose of 66 Gy with a median overall treatment time (OTT) of 40 days delivered by a concomitant boost (CCB), and a median dose of 60 Gy with a median OTT of 47 days was administered for six patients by conventional fractionation (CF). The 3-year overall survival (OAS) and local control (LC) rates were 43.8% and 75.0%, respectively. The 3-year LC rate was 90.0% for the CCB group, 50.0% for the CF group (P = 0.0692); 100% for OTT ≤42 days, 42.9% for OTT ≥43 days (P = 0.0095). No severe acute and late adverse effects were encountered for any of the patients. These outcomes suggest that EBRT with a CCB program may be a promising radical treatment for cervical cancer that provides better LC with minimal complications, especially in cases where ICBT cannot be performed.

45 Gy versus 54 Gy of accelerated hyperfractionated thoracic radiotherapy for patients with limited-stage small-cell lung cancer.

e20104Background: The optimal dose of accelerated hyperfractionated radiotherapy (AHF-RT) for limited-stage small-cell lung cancer (L-SCLC) remains unknown. The purpose of this study was to evaluat...