Patterns of Care Study (PCS) was introduced into Japan. Significant differences in their process were observed for esophageal and cervix cancer patients between university hospitals/cancer centers and other public hospitals. The influence of such differences on the outcome will be carefully analyzed. The differences in Structure such as external beam energy and number of FTE radiation oncologist were found. Thus, an appropriate guideline to improve the current structure will be required based on the Outcome. In the United States, their Processes showed higher score than those in Japan without any significant differences between two types of institutions. The number of FTE radiation oncologists in the United States showed higher value and corresponded to these Process results. Chemoradiotherapy for esophageal cancer was widely disseminated with significant shift of external dose to lower range. In Japan, surgery was more frequently performed than in the United States. In the present PCS'95-97, detailed information on esophageal cancer, cervix cancer, breast cancer, lung cancer and prostate cancer are rigorously surveyed by our audit team. Its methodology, progress, and future goal are presented here.

View full abstract

The usefulness of low-dose external beam irradiation (LDE) to the oral cavity and upper neck with or without low-dose chemotherapy before local irradiation in stage I and II tongue carcinoma were evaluated. From 1978 to 1996, fifty-three patients with stage I and II tongue carcinoma (stage I: 17, stage II: 36) were treated with radiation therapy. Tongue tumors were irradiated with radium needle implantation in 49 patients, and with an electron beam in 4 patients. In 17 of the 53 patients (stage I: 2, stage II: 15) with an unfavorable primary tumor such as a deep infiltrated tumor, ill-defined tumor or large T2 tumor, LDE with a total dose of 25 Gy or less and a daily fraction size of 2.5 Gy was administered before local irradiation. In 8 of 17 patients, low-dose chemotherapy with peplomycine or bleomycine was administered concurrently. Five-year survival rates of patients with or without LDE were 79.4% and 67.9%, respectively. Five-year local control rates of patients with or without LDE were 68.8% and 82.9%, respectively. Five-year neck disease free rates of patients with or without LDE were 92.9% and 66.7%, respectively (P<0.05). Mandibular osteonecrosis occurred in 1 of 17 (5.9%) patients with LDE and in one of 36 (2.8%) patients without LDE. In stage I and II tongue carcinoma, LDE with a daily fraction size of 2.5 Gy with or without concurrent low-dose chemotherapy is effective for subclinical neck lymph node metastases, but it may be insufficient as supporting therapy for local control in patients with unfavorable primary tumors.

View full abstract

Purpose: In the simulation of radiation therapy for breast-conserving treatment using isocentric treatment technique (coplanar method) by x-ray simulator, complex measurement and calculations are needed to determine the angle of the radiation portals and the coordinates of the isocenter. The simulation requires abundant time and skills. We developed simple software for calculating the angle of the radiation portals and the coordinates of the isocenter in simulation for breast irradiation following breast-conserving surgery. The aim of this study was to ascertain the applicability of the software to various shapes of conserved breasts.
Materials and methods: The software was written in Basic language to be used on a personal computer (MS-DOS). By giving the thickness and width of a patient at the level of the breast, the angle of the radiation portals and the coordinates of the isocenter were automatically calculated. The software was examined whether calculated figures were applicable to x-ray simulation using a phantom breast. The software were also checked in a total of 14models using various shapes of breast. Dose distributions in the breasts were calculated on thecomputer.
Results: Simulation radiographs of the phantom breast demonstrated accordance of radiopaque marks attached on the lateral edge of the two portals, showing the calculations ofsoftware were correct. The software was applicable to 14 breast models by choosing the size of the portals. Dose distribution calculated showed absence of improper deviation of the irradiated dose.
Conclusions: The software was applicable to various breast shapes. The simulation by x-ray simulator can be easily done with the help of the software.

View full abstract

Purpose: To compare the results of treatment performed with and without team practice in glottic laryngeal cancer patients, including local control rate and preservation of voice.
Materials and Methods: Since April 1991, radiation oncologists, radiologists and otolaryngologists have worked in close collaboration to treat head and neck cancerpatients in the Kurume University Hospital. Treatment results of a total of 419 patients with glottic cancer were compared with or without team practice. In group A (period, Jan 1978 to Mar 1991), 237 glottic laryngeal cancer patients were treated before team practice. In group B (period, Apr 1991 to Mar 1997), 182 patients were treated with team practice. All patients had histologically proven invasive squamous cell carcinoma. Follow-up period was at least 2 years.
Results: In group A, a laser was preferentially used for T1 lesions (T1a: 41 lesions, 52.6%, Tlb: 7 lesions, 15.6%), and partial laryngectomy or total laryngectomy was preferentially used for T2 lesions (partial laryngectomy: 21 lesions, 30.9% and total laryngectomy: l0 lesions, 14.7%). On the other hand, in group B, 126 (81.8%) T1 and T2 lesions were treated with radical radiation with or without laser. Local control rate of T1 and T2 cancer improved significantly from 78.3% for group A patients to 91.2% for group B patients (p<0.01). Larynx preservation rate improved slightly from 88.6% to 95.0%. Five year cause-specific survival rate for all stageI to IV patients improved from 94.8% to 96.5%, but was not significant. Relapse-free survival rate improved significantly from group A to group B: from 75.1% to 87.4%(p<0.01).
Conclusion: Team practice has effective results in improved local control and preservation of natural voice for patients with glottic carcinoma.

View full abstract

We retrospectively evaluated the impact of accelerated hyperfractio-nation (AHF) on tumor control, as well as the side effects of AHF on normal tissues. The subjects consisted of 226 patients with laryngeal squamous cell carcinoma who received radical radiation (total dose above 50 Gy) at Jichi Medical School. Infield local control rates were compared between the following 2 groups: a group consisting of 105 patients who received 10 fractions per week (F/W)(AHF group) and a group consisting of 121 patients who received 3 or 5 F/W (25 patients received 3 F/W and 96 5 F/W, group B). The median follow-up time was 6.2 years. The 5-year control rate in stage I+II tumors was significantly higher in the AHF group than in group B (97% vs. 74%, p=0.0003). In stage III+IV tumors, the 5-year control rate was also significantly higher in the AHF group than in group B (72% vs. 22%, p<0.00001). Although significantly intensive early mucosal reactions were noted in the AHF group, it were fairly tolerable.
AHF showed a similar late complication rate to that of the conventional regimen (5 F/W). Therefore, it was suggested that AHF (60-62 Gy/40 times/4 weeks) was a good fractionation regimen demonstrating a higher therapeutic gain.

View full abstract

[PURPOSE] Radiation therapy (RT) following breast conserving surgery (BCS) for early breast cancer has been performed only in those patients with some unfavorable prognostic factors, i. e. young age, positive nodes, positive margins, etc at our facility. The purpose of this study was to retrospectively compare the outcomes of (BCS) with or without RT.
[MATERIALS AND METHODS] From November 1989 to August 1998, 161 patients (163 breasts) underwent BCS in our facility. Of these, 38 patients (39 breasts) received RT to the breast (RT (+) group) and the remaining 123 patients (124 breasts) did not receive RT (RT (-) group). Patients in the RT (+) group were significantly younger and had larger tumors, more positive nodes, extensive intraductal spread and positive margins.
[RESULTS] Median follow-up period was 37 months (range 2.4-108 months). Ten patients in the RT (-) group and 1 patient in the RT (+) group developed ipsilateral breast recurrence. The 5-year ipsilateral breast reccurence rates were 9.9% in the RT (-) group and 3.4% in the RT (+) group (N. S.), and the 5-year breast conserving rates were 90.3% and 96.0%(N. S.), respectively. The five-year disease specific survival rates were 96.6% and 96.0%, respectively (N. S.). Multivariate analysis revealed that non-invasive cancers (p=0.0095), lymphatic invasion (p=0.05) and RT (-)(p=0.07) had higher ipisilateral breast reccurence rate. Severe complications related to RT have not been observed.
[CONCLUSION] Even though patients in the RT (+) group had more risk factors for local recurrence, both groups showed identical ipsilateral breast recurrence rates and survival rates.

View full abstract

To analyze various parameters affect local control, we reviewed the results of radiotherapy for early glottic carcinoma. Between 1977 and 1997, 64 patients with untreated early glottic carcinoma and four patients with recurrent early glottic carcinoma were analyzed retrospectively. All tumors were classified as follows; T1 (n=56), T2 (n=12); well differentiated (n=33), moderately (n=25), poorly (n=1), unknown (n=9); very small tumor (VST)(n=46), small tumor (ST)(n=22). All patients were treated utilizing a cobalt-60 unit to a total dose that ranged from 56 Gy to 64 Gy (mean 60 Gy). The mean treatment time was 44 days (range 38-49). The local control rates at 2 years and 5 years for all patients were 85% and 78%, respectively. On univariate analysis, tumor size (p=0.0146) and recurrent or untreated tumor (p=0.0226) affected local control. On multivariate analysis, tumor size (p=0.0273) and recurrent or untreated tumor (p=0.0495) were also significant factors that affected local control.

View full abstract

Purpose: To improve tumor control of oral cancers by postoperative radiotherapy, the relation between radiation fields and recurrence patterns was studied according to postoperative tumor residuals.
Methods: Between 1984 and 1998, 36 patients with squamous cell carcinoma of the oral cavity underwent postoperative radiotherapy. They consisted of 5 stage I-IIIs, 15 stage IVs, and 16 recurrences. There were 19 local residuals (7 microscopically and 12 macroscopically) and 8 nodal residuals (5 microscopically and 3 macroscopically). The mean dose of postoperative irradiation was 52 Gy in 25 fractions over 35 days.
Results: The overall 5-year survival rate and disease-free survival rate were 38% and 21%, respectively. Twenty patients had recurrences within 6 months and 4 patients had recurrences at the primary site around 4 years after irradiation. Recurrence rates were significantly associated with the tumor residuals and the number of positive nodes. The tumor control rates were 5/16 (31%) for local residuals alone, 2/5 for nodal residuals alone, and 0/3 for both local and nodal residuals. For 9 patients without nodal disease, radiation fields to the primary site developed 3 in-field recurrences and no out-of-field recurrence (control rate: 6/9). For 9 patients with pathologically positive nodes completely resected and without local residuals, the radiation fields to the neck only developed late recurrences at the primary site in 4 of 5 patients, while the radiation fields also including the primary site developed no recurrence at the primary site in 4 patients (control rate: 3/9). The recurrence patterns were significantly different between them. For 10 patients with pathologically positive nodes completely resected and with local residuals, radiation fields mainly to local residuals developed 3 out-of-field recurrences of 4 nodal recurrences (control rate: 2/10). The out-of-field recurrence rates were not different statistically between parallel as opposed to lateral ports and hemi-lateralized fields. No out-of field recurrence occurred in patients with irradiation fields including lower neck nodes.
Conclusion: Radiation fields according to postoperative residuals played a role for loco-regional control. For patients without nodal disease, the radiation field including only the primary site was recommended considering the patient's quality of life. For patients with nodal disease, large field adding the primary site and lower neck field would improve the postoperative irradiation results. However, the hemi-lateralized radiation fields instead of the parallel as opposed to lateral ports is possible for some patients.

View full abstract

Twenty patients with superficial esophageal cancers were treated with external beam radiotherapy and intraluminal brachytherapy. The median age was 75 years, and most patients had other systemic concomitant disease. The median dose of external beam radiotherapy was 60 Gy (40-60), and the median dose of brachytherapy was 10 Gy/4 fx.(10-18 Gy). The 2-year overall and disease-free survival rates were 90% and 94%, respectively. Acute adverse effects in the esophagus were relatively mild in most patients (Grade 0-1 according to RTOG Acute Radiation Morbidity Scoring Criteria), all patients were treated without interruption. Radiation induced pneumonitis (Grade 2) was found in one patient. Late adverse effects in the esophagus were mild in 18 patients without local recurrence (Grade 0; 14 patients, Grade 1; 4 patients, according to RTOG/EORTC Late Radiation Morbidity Scoring Scheme). No severe late adverse effects including stenosis, bleeding and fistula was found. The swallowing of food was excellent in all patients.

View full abstract

Initial swelling followed by gradual shrinkage is regarded as usual in the Gamma Knife treatment of acoustic neurinomas. We developed a mathematical model representing these changes with 3 independent variables, and a relationship was revealed between these variables and a dose-volume histogram. One hundred and fifty-one patients were treated for acoustic neurinomas between 1992 and 1997 at our facility. Of these, 84 cases could be evaluated with our mathematical model because they were followed by MRI for more than 12 months and at least 5 studies were performed. Peripheral, average and maximum doses were 13.9±3.1, 18.6±4.2 and 28.6 ± 7.5 Gy, respectively. Pretreatment volumes were 5.5±9.3 cm3. There were 3 groups, stable (16 cases), rapidly swelling and shrinking (41 cases) and slow-growing and reducible (27 cases). The second group had a small mean time constant of 0.3 months for the initial growing and-23 months for the contiguous shrinkage. The values for the third group were 1 and-43 months, respectively. The degree of swelling in the third group was 3 times higher than that in the second group. The low frequency of the dose distribution over 26 Gy discriminated the members of the second group from the others (p<0.0426), witch indicated that significantly higher doses may not produce good results.

View full abstract

The ICRU rectal doses by intracavitary radiotherapy (ICRT) using Tandem and Ovoid in 144 patients with uterine cervix cancer were calculated. Eighty four of 144 patients were treatecl by external radiotherapy (ERT) and low dose rate ICRT (45-55 Gy/3 fractions/3 weeks to point A), and 60 were treated by ERT and high dose rate ICRT (30 Gy/6 fractions/3 weeks). A sigmoid curves of the ICRU rectal dose by ICRT versus rectal injury rate of NIRS grade 2 or higher for each whole pelvis dose by ERT were established. The 10% rectal injury doses were determined for each of the whole pelvis ERT doses, 0 Gy, 10 Gy, 20 Gy and 21 Gy, from the sigmoid curve. The 10% complication doses were LDR: 41 Gy, HDR: 51 Gy, in whole pelvis ERT dose of 0 Gy group. The dose rate effect LDR/HDR was 1.24. It was 1.17 in ERT 10 Gy group, 1.23 in ERT 20 Gy group, 1.26 in ERT 21 Gy group. It was 1.24 in ERT 0-20 Gy group.

View full abstract