Carbon ion radiation therapy for prostate cancer: results of a prospective phase II study.

BACKGROUND AND PURPOSE: To determine the efficacy and feasibility of carbon ion radiotherapy (C-ion RT) for prostate cancer. PATIENTS AND METHODS: Between April 2000 and November 2003, 175 patients received C-ion RT using a recommended dose fractionation (66.0 GyE/20 fractions) established from prior studies. C-ion RT alone was performed for 33 patients constituting a low-risk group (Stage < or =T2a and PSA <20 ng/ml and Gleason score < or =6); the remaining 142 high-risk patients received an additional androgen deprivation therapy (ADT). RESULTS: The 4-year overall survival and bNED rates were 91% and 87%, respectively. Local control was achieved in all but one patient. The 4-year bNED rates were 87% in the low-risk group and 88% in the high-risk group. In very advanced diseases (Stage > or= T3a or PSA > or= 20 ng/ml or Gleason score > or =8), there was significant difference in the bNED rate according to period of ADT administration (ADT > or =24 months: 93%, ADT <24 months: 73%, p<0.01). Grade 2 late toxicities developed in 4 patients (2%) for the rectum and 9 patients (5%) for the genitourinary system but no Grade 3 or higher toxicity was observed. CONCLUSIONS: The effectiveness of C-ion RT for prostate cancer has been well confirmed. Based on these results, new study of a C-ion RT modified for the administration strategy of ADT according to the patient risk has been started by dividing patients into 3 groups, high-risk, intermediate-risk, and low-risk.     

The effectiveness of preoperative intraluminal brachytherapy in preventing wall penetration and nodal involvement of rectal carcinomas

(Received for publication on Oct. 15, 1998; accepted on Sept. 17, 1999)     

The effects of 30% and 60% xenon inhalation on pial vessel diameter and intracranial pressure in rabbits

Xenon may increase cerebral blood flow and intracranial pressure (ICP). To evaluate the effects of xenon on brain circulation, we measured pial vessel diameter changes, CO(2) reactivity, and ICP during xenon inhalation in rabbits. Minimum alveolar anesthetic concentration (MAC) for xenon was established in rabbits (n = 6). By using a cranial window model, pial vessel diameters were measured at 30% and 60% xenon inhalation and in time control groups (n = 15). ICP, mean arterial blood pressure, and heart rate were recorded during 30% and 60% xenon inhalation (n = 5). Pial vessel diameters were measured during hypocapnia and hypercapnia conditions in 60% Xenon and Control groups (n = 14). MAC for xenon was 85%. Xenon (0.35 and 0.7 MAC) dilated the arterioles (10% and 18%, respectively) and venules (2% and 4%, respectively) (P < 0.05). Dilation of arterioles was more prominent than that of venules. ICP, mean arterial blood pressure, and heart rate did not change during xenon inhalation. No difference in CO(2) reactivity was observed between Xenon and Control groups (P = 0.79). Sixty percent xenon (0.7 MAC) dilated brain vessels, but venule changes were small. Xenon did not increase ICP and preserved CO(2) reactivity of the brain vessels. IMPLICATIONS: Xenon might increase cerebral blood flow; however, 0.7 minimum alveolar anesthetic concentration xenon preserved both low intracranial pressure and CO(2) reactivity of the cerebral vessels in the normal rabbit.     

Radiotherapy for uterine cervical cancer: results of the 1995-1997 patterns of care process survey in Japan

OBJECTIVE: The aim of this study is to establish Japanese national practice patterns for uterine cervical cancer patients who received radiotherapy without surgery. METHODS: The Japanese Patterns of Care Study (JPCS) conducted a national survey of 73 institutions using two-stage cluster sampling, and collected specific information on 591 patients with uterine cervical cancer treated by radiotherapy without planned surgery between 1995 and 1997. RESULTS: The median age of the patients was 70 years. Karnofsky performance status (KPS) was >/=90 for 37%. Most patients (95%) had histology of squamous cell carcinoma. Ten percent were stage I, 29% stage II, 48% stage III and 13% stage IVA. Photon beams of 10-14 MV were the most used for external beam radiotherapy (EBRT). The beam energy utilized varied significantly by institution strata. Midline block was used in approximately 70% of institutions. Intracavitary brachytherapy (ICBT) was performed in 77%. Institution strata correlated significantly with the ICBT application. The majority of patients (89%) were treated with high-dose-rate (HDR) ICBT. The median single point A dose of HDR-ICBT was 600 cGy. The median summated point A dose from EBRT and HDR-ICBT was 5800 cGy (range: 1196-8600). The median overall treatment time including ICBT was 49 days. Twenty-four percent of the patients received chemotherapy. Concurrent chemoradiation was performed in 5%. CONCLUSIONS: The JPCS established the Japanese national practice patterns of care for uterine cervical cancer patients treated with radiotherapy without planned surgery between 1995 and 1997. This survey demonstrated that the institutional strata significantly affected several practice patterns.     

Patterns of care study in Japan

BACKGROUND: The Patterns of Care Study (PCS), started in the 1970's, is a well-known study used for clinical quality assurance (QA) in radiation oncology in the United States. PCS has been introduced in Japan since 1996. METHODS: Three national PCS surveys have been performed by means of external audit to evaluate patterns of care for the patients with carcinoma of any of esophagus and cervix treated with radiation between 1992 and 1994, for those with carcinoma of any of esophagus, cervix, breast, lung and prostate between 1995 and 1997, and for those with any of the five disease sites between 1999 and 2001. In the first PCS, feasibility of the study was confirmed. In the second PCS, two-stage cluster sampling of institutions and patients was performed and national averages for the survey items were calculated as QA measures. In the third PCS, additional imaging data were collected. The Japan/USA PCS workshops were held at San Francisco in 2001 and at Tokyo in 2003. RESULTS: Significant variations in process and structure were observed according to institutional stratification. In academic institutions, external beam energy > or =6 MV for deep-seated tumors of esophagus, lung, prostate and cervix, and brachytherapy for those of cervix and esophagus were used more frequently. There was an average of less than one full-time equivalent radiation oncologist in most non-academic institutions. These variations influenced the outcomes. There were also significant differences between USA and Japan in various aspects, e.g. a difference in radiation dose of 20% for uterine cervix cancer patients. It is higher in the USA. The number of new cancer patients requiring radiation is increasing steeply (120,000 in 2000 and 170,000 in 2005). Based on PCS data, structural guidelines were published and distributed throughout Japan. CONCLUSION: PCS is useful for establishing the clinical QA for radiation oncology as well as other specialties through detailed monitoring and evaluation of their structures, processes and outcomes.