Phase III trial of high and low dose rate interstitial radiotherapy for early oral tongue cancer

: Oral tongue carcinomas are highly curable with radiotherapy. In the past, patients with tongue carcinoma have usually been treated with low dose rate (LDR) interstitial radiation. This Phase III study was designed to compare the treatment results obtained with LDR with those obtained with high dose rate (HDR) interstitial radiotherapy for tongue carcinoma.

: The criteria for patient selection for the Phase III study were: (a) presence of a T1T2N0 tumor that could be treated with single-plane implantation, (b) localization of tumor at the lateral tongue border, (c) tumor thickness of 10 mm or less, (d) performance status between O and 3, and (e) absence of any severe concurrent disease. From April 1992 through December 1993, 15 patients in the LDR group (70 Gy/4 to 9 days) and 14 patients in the HDR group (60 Gy/10 fractions/6 days) were accrued. The time interval between two fractions of the HDR brachytherapy was more than 6 h.

: Local recurrence occurred in two patients treated with LDR brachytherapy but in none of the patients treated with HDR. One- and 2-year local control rates for patients in the LDR group were both 86%, compared with 100% in the HDR group (p = 0.157). There were four patients with nodal metastasis in the LDR group and three in the HDR group. Local recurrence occurred in two of the four patients with nodal metastases in the LDR group. One- and 2-year nodal control rates for patients in LDR group are were 85, compared with 79% in the HDR group.

: HDR fractionated interstitial brachytherapy can be an alternative to traditional LDR brachytherapy for early tongue cancer and eliminate the radiation exposure for medical staffs.     

The trail of the development of high-dose-rate brachytherapy for cervical cancer in Japan

The differences in radiotherapeutic treatment systems for cervical cancer between the United States and Japan can be attributed either to the tolerance of high-risk organs, or dosimetry itself. High-dose-rate (HDR) brachytherapy is the standard treatment for uterine cervix carcinoma in Japan. In addition, HDR Co-60 afterloading machines have been gradually replaced with Ir-192 micro-source afterloading machines during the past ten years. This implies that it has now become impossible to conduct a prospective comparative study of HDR versus low-dose-rate (LDR) brachytherapy for cervical cancer in Japan. An examination of the history of HDR intracavitary radiotherapy for uterine cervix carcinoma in Japan led us to the conclusion that HDR intracavitary brachytherapy for the treatment of cervical cancer is as effective as LDR intracavitary brachytherapy in terms of both survival and complications. In Japan, studies on the former can be drawn from a long experience of more than 35 years.     

High Dose Rate versus Low Dose Rate Interstitial Radiotherapy for Carcinoma of the Floor of Mouth

Purpose: Patients with cancer of the floor of mouth are treated with radiation because of functional and cosmetic reasons. We evaluate the treatment results of high dose rate (HDR) and low dose rate (LDR) interstitial radiation for cancer of the floor of mouth.Methods and Materials: From January 1980 through March 1996, 41 patients with cancer of the floor of mouth were treated with LDR interstitial radiation using ¹⁹⁸Au grains, and from April 1992 through March 1996 16 patients with HDR interstitial radiation. There were 26 T1 tumors, 30 T2 tumors, and 1 T3 tumor. For 21 patients treated with interstitial radiation alone, a total radiation dose of interstitial therapy was 60 Gy/10 fractions/6–7 days in HDR and 85 Gy within 1 week in LDR. For 36 patients treated with a combination therapy, a total dose of 30 to 40 Gy of external radiation and a total dose of 48 Gy/8 fractions/5–6 days in HDR or 65 Gy within 1 week in LDR were delivered.Results: Two- and 5-year local control rates of patients treated with HDR interstitial radiation were 94% and 94%, and those with LDR were 75% and 69%, respectively. Local control rate of patients treated with HDR brachytherapy was slightly higher than that with ¹⁹⁸Au grains (p = 0.113). For late complication, bone exposure or ulcer occurred in 6 of 16 (38%) patients treated with HDR and 13 of 41 (32%) patients treated with LDR.Conclusion: HDR fractionated interstitial brachytherapy can be an alternative to LDR brachytherapy for cancer of the floor of mouth and eliminate radiation exposure for the medical staff.     

Patterns of brachytherapy practice for patients with carcinoma of the cervix (1996-1999): a patterns of care study

PURPOSE/OBJECTIVE: To analyze the details of brachytherapy practice in patients treated for carcinoma of the cervix in the United States between 1996 and 1999. METHODS AND MATERIALS: Radiation facilities were selected from a stratified random sample. Patients were randomly selected from lists of eligible patients treated at each facility. A total of 442 patients' records were reviewed in 59 facilities to obtain data about patients' characteristics, evaluation, tumor extent, and treatment. National estimates were made using weights that reflected the relative contribution of each institution and of each patient within the sampled institutions. From our survey we estimate that 16,375 patients were treated in the United States during this study period. Unless otherwise specified, brachytherapy practice was based on the 408 patients who had their brachytherapy or all their treatment at the surveyed facility. Results: A total of 91.5% of patients underwent brachytherapy at the initial treating institution; 8.5% were referred to a second site for brachytherapy. Forty-two percent of U.S. facilities referred at least some patients to a second facility for brachytherapy. Of U.S. facilities that treated < or =2 eligible patients per year, 61% referred all of their patients to a second facility for brachytherapy or treated with external RT alone; none of the U.S. facilities with larger experience (>2 eligible patients per year) referred all their patients to a second facility for brachytherapy treatment, but 28% referred some patients to an outside facility for brachytherapy. Overall, 94% of patients who completed treatment with curative intent received brachytherapy. Of these patients who had brachytherapy, 77.8%, 13.3%, and 0.9%, respectively, were treated with low-dose-rate (LDR), high-dose-rate (HDR), or a combination of HDR and LDR brachytherapy; 7.9% had interstitial brachytherapy (5.7% LDR and 1.9% HDR, 0.3% mixed). In facilities that treated >2 patients per year, 15.5% and 9.4% of brachytherapy procedures included HDR or interstitial, respectively; in facilities that treated fewer patients, 3.4% had HDR brachytherapy, and only 1.2% had interstitial brachytherapy. Patients treated with LDR intracavitary radiotherapy had one (23.5%), two (74.1%), or three (2.4%) implants. For patients treated with curative intent who completed radiation therapy with LDR intracavitary radiation therapy without hysterectomy, the median brachytherapy dose to Point A was 40.3 Gy, and the median total dose to Point A was 82.9 Gy. Patients were treated with HDR intracavitary radiation therapy using a variety of treatment schedules using 1-2 fractions (7.5%), 3-4 fractions (17.4%), 5-6 fractions (38.5%), 7-9 fractions (33.5%), or 12 fractions (3%). Fraction sizes were <500 cGy (29.5%), 500-<600 (25.2%), 600 (28.1%), >600 (8%), or unknown (9.2%). For patients treated with HDR, the median total dose to Point A (corrected for fraction size using a alpha/beta = 10) was 85.8 Gy (range: 56.2-116.1 Gy). At institutions treating <500 new patients per year, the percentage of patients receiving a brachytherapy dose <40 Gy was significantly higher than at institutions treating > or =500 new patients per year (p < 0.0001). For LDR intracavitary radiation therapy, 5.8% had neither bladder nor rectal doses recorded for any of their implants, whereas in HDR intracavitary radiation therapy, 73.4% had neither bladder nor rectal doses recorded for any of their implants. The median total duration of radiation therapy was identical for patients who had HDR or LDR intracavitary radiation therapy (57 days). For LDR at institutions treating <500 new patients per year, the percentage of patients with treatment duration >56 days was significantly greater than at institutions > or =500 new patients per year (p = 0.002). Of the patients who had LDR intracavitary radiation therapy implants, 65% were treated using tandem and shielded Fletcher-Suit-Delclos colpostats; other patients had mini ovoids (10.9%), cylinders (3.9%), Henschke (3.7%), or other/mixed applicators (16.5%). In contrast, of patients treated with HDR intracavitary radiation therapy, 68.7% had tandem and rings, 18.2% Fletcher-Suit-Delclos ovoids, 7.5% mini ovoids, 2.3% cylinders, and 3.2% other or mixed applicators. Conclusions: The median duration of treatment and median Point A dose were very similar for patients treated with HDR or LDR. Patients with HDR were treated using a variety of treatment schedules. Different applicator types were favored for LDR vs. HDR. Of patients treated with HDR, 73.4% had no brachytherapy bladder or rectal doses recorded, suggesting that full dosimetric calculations were performed only for the first fraction in many institutions. Facility size significantly impacted on referral to another institution for brachytherapy, brachytherapy dose, and treatment duration.     

High versus low dose rate intracavitary irradiation for adenocarcinoma of the uterine cervix.

BACKGROUND: Traditionally, low dose rate (LDR) brachytherapy has been used as a standard modality in the treatment of patients with carcinoma of the uterine cervix. The purpose of this work was to evaluate the effects of high dose rate (HDR) brachytherapy on patients with adenocarcinoma of the uterine cervix and to compare them with the effects of LDR brachytherapy. METHODS: From January 1971 to December 1992, 104 patients suffering from adenocarcinoma of the uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University. LDR brachytherapy was carried out on 34 patients and HDR brachytherapy on 70 patients. In the LDR group, eight patients were in stage IB, six in IIA, 12 in IIB, three in IIIA and five in IIIB. External radiation therapy was delivered with 10 MV X-rays, 2 Gy fraction per day, total dose of whole pelvis 36-52 Gy (median 46 Gy). LDR radium intracavitary irradiation was performed with a Henschke applicator, 37-59 Gy targeted at point A (median 43 Gy). In the HDR group, there were 16 patients in stage IB, six in IIA, 32 in IIB and 16 in IIIB. The total whole pelvis dose of external radiation was 40-50 Gy (median 44 Gy), daily 1.8-2.0 Gy. HDR Co-60 intracavitary irradiation was performed with a remotely controlled after-loading system (RALS), 30-48 Gy (median 39 Gy) targeted at point A, three times per week, 3 Gy per fraction. RESULTS: The 5-year overall survival rate in the LDR group was 72.9, 61.9 and 35.7% in stage I, II and III, respectively and the corresponding figures for HDR were 87.1, 58.3 and 43.8% (p > 0.05). There was no statistical difference between the HDR group and the LDR group in terms of the 5-year overall survival rate from adenocarcinoma of the uterine cervix. There was a late complication rate of 12% in the LDR group and 27% in the HDR group. The incidence of late complications in stages II and III was higher in the HDR group than in the LDR group (31.6 vs 16.7% in stage II, 37.3% vs 12.5% in stage III, p > 0.05). No prognostic factors were evident in the comparison between the two groups. CONCLUSION: There was no difference in terms of 5-year survival rate in the patients with adenocarcinoma of the uterine cervix between those treated with HDR and those treated with LDR brachytherapy. Even though late complication rates were higher in the HDR group, most of them were classified as grade I. This retrospective study suggests that HDR brachytherapy may be able to replace LDR brachytherapy in the treatment of adenocarcinoma of the uterine cervix.     

Brachytherapy: Current Status and Future Strategies — Can High Dose Rate Replace Low Dose Rate and External Beam Radiotherapy?

Brachytherapy delivers the most conformal high dose radiotherapy possible to the prostate, using either a low dose rate (LDR) or high dose rate (HDR) technique. It may be used either alone as monotherapy or in combination with external beam radiotherapy (EBRT) as a local boost. Comparative efficacy studies, including one randomised controlled trial, consistently show higher cancer control rates when brachytherapy is used compared with EBRT alone, with even some evidence of improvement in survival. There are now extensive mature data supporting the use of LDR as monotherapy for patients with low-risk and selected intermediate-risk disease, with most series reporting long-term disease control rates of over 90% after high-quality implants. HDR is most commonly combined with EBRT to treat intermediate- and high-risk disease, with disease control rates of over 90% reported. The low alpha/beta ratio of prostate cancer combined and the ability to optimally sculpt dose distribution provides the biological and dosimetric rationale for HDR. HDR enables more consistent implant quality than LDR, with evidence of lower acute and late toxicity. Many dose and fractionation schedules of HDR in combination with EBRT have been investigated, but a single fraction of 10–15 Gy is commonly combined with EBRT to a dose of 40–50 Gy to treat intermediate- and high-risk disease. High disease control rates are also reported with HDR as monotherapy, particularly in patients with low- and intermediate-risk disease. Although older series have delivered four to six fractions of HDR, there is growing evidence to support the delivery of HDR in three or even two fractions. Single-fraction HDR monotherapy is now being investigated and if early data are confirmed with longer follow-up, may well become the treatment of choice for many men with localised prostate cancer.     

Results of low- and high-dose-rate interstitial brachytherapy for T3 mobile tongue cancer.

PURPOSE: To evaluate the treatment results of low-dose-rate (LDR) and high-dose-rate (HDR) interstitial brachytherapy (ISBT) for T3 mobile tongue cancer. MATERIAL AND METHODS: Between 1974 and 1992, 61 patients with T3 mobile tongue cancer were treated with LDR ISBT using (192)Ir hairpins with or without single pins. In addition, between 1991 and 1999, 14 patients were treated with HDR ISBT. For nine patients treated with ISBT alone, the total dose was 59-94 Gy (median 72 Gy) within one week in LDR ISBT and 60 Gy/10 fractions/5 days in HDR ISBT. For 66 patients treated with a combination therapy of external beam radiotherapy (EBRT) and ISBT, the total dose was 12.5-60 Gy (median 30 Gy) of EBRT and 50-112 Gy (median 68 Gy) within 1 week in LDR ISBT or 32-60 Gy (median 48 Gy)/8-10 fractions/5-7 days in HDR ISBT. RESULTS: The 2- and 3-year local control rates of all patients were both 68%. The 2- and 3-year local control rates of patients treated with LDR ISBT were both 67%, and those with HDR ISBT were both 71%. The local control rate of patients treated with HDR ISBT was similar to those with LDR ISBT. CONCLUSIONS: ISBT for T3 mobile tongue cancer is effective and acceptable. The treatment result of HDR ISBT is almost similar to that of LDR ISBT for T3 mobile tongue cancer.     

Advances in brachytherapy--focusing on the permanent implant for early prostate carcinoma

Even in the modern era of advanced external radiotherapy, brachytherapy is an important and useful modality of radiotherapy. In North America and Europe, it has been noted that the proportion of prostate cancer patients treated by HDR or LDR interstitial brachytherapy is rapidly increasing, as it offers several practical and theoretical advantages over external radiotherapy. HDR treatment with 192Ir remote afterloader provides an optimized dose distribution controlled by an accurate dwell time and position of 192Ir source. LDR brachytherapy is a simple, minimally invasive, and outpatient based procedure that avoids hospitalization and allows the patient an early recovery and rapid return to normal activities. It has produced good 10-year outcome with relatively low morbidity. Although in Japan this treatment was behind North America and Europe, the 125I-seed source was approved by the Japanese FDA and a rule for patient discharge was developed recently. The first case was treated in September 2003 and this treatment is expected to become an important option for early prostate cancer. Several areas of brachytherapy including treatment planning, choice of radionuclide, treatment procedure, and treatment outcome are discussed in this paper.     

高剂量率192铱后装机腔内加外照射治疗宫颈癌60例临床分析

目的:探讨高剂量率192铱后装腔内加体外照射治疗宫颈癌的疗效及副作用等。方法:2005年3月至2007年1月本院放疗中心共60例宫颈癌患者,采用8MV-X线直线加速器全盆照射,开始体外全盆腔照射,5次/周,2Gy/次,剂量25-40Gy;然后中间挡铅,4个野照射,5次/周,2Gy/次,宫旁剂量20-25Gy:同时腔内治疗,1次/周,6Gy/次,剂量为35-40Gy。腔内治疗采用ZL-HDR18铱高剂量率后装治疗机,全部病例均宫颈阴道同时进行。腔内治疗每周1次,A点剂量36-40GY/6-7F/6-7w,腔内治疗当日停体外照射,治疗时间56-77天。结果:CR+PR 100%,随访超过3年,随访率达95%,3年生存率Ⅱ期88.3%,Ⅲ期82.9%;早期放射性直肠反应发生率为12.4%,膀胱反应发生率5.2%;晚期放射性直肠炎发生率13.8%,膀胱炎3.8%。结论:高剂量率192铱后装机腔内加体外治疗宫颈癌的疗效满意,患者生存率较高,耐受好,并发症少。     

High-dose-rate versus low-dose-rate intracavitary brachytherapy for carcinoma of the cervix

High-dose-rate (HDR) remote afterloading intracavitary brachytherapy has been widely used in the treatment of carcinoma of the cervix in Europe and Asia since the 1960's. Recently, there has been an increase of interest in the use of this technique in North America. Most of the non-randomized studies suggest similar survival, local control, and complication rates using fractionated high-dose-rate remote afterloading intracavitary brachytherapy combined with external beam irradiation compared to historical or concurrent low-dose-rate (LDR) controls. However, the techniques as well as the dose fractionation schedules used in different institutions are variable. The optimal technique and dose fractionation scheme has yet to be established through systematic clinical trials.     

High-dose-rate versus low-dose-rate brachytherapy in the treatment of cervical cancer: analysis of tumor recurrence--the University of Wisconsin experience

Purpose: To retrospectively compare the clinical outcome for cervical cancer patients treated with high-dose-rate (HDR) vs. low-dose-rate (LDR) brachytherapy.

Methods and Materials: One hundred ninety-one LDR patients were treated from 1977 to 1988 and compared to 173 HDR patients treated from 1989 to 1996. Patients of similar stage and tumor volumes were treated with identical external beam fractionation schedules. Brachytherapy was given in either 1 or 2 LDR implants for the earlier patient cohort, and 5 HDR implants for the latter cohort. For both patient groups, Point A received a minimum total dose of 80 Gy. The linear-quadratic formula was used to calculate the LDR dose-equivalent contribution to Point A for the HDR treatments. The primary endpoints assessed were survival, pelvic control, relapse-free survival, and distant metastases. Endpoints were estimated using the Kaplan-Meier method. Comparisons between treatment groups were performed using the log-rank test and Cox proportional hazards models.

Results: The median follow-up was 65 months (2 to 208 months) in the LDR group and 22 months (1 to 85 months) in the HDR group. For all stages combined there was no difference in survival, pelvic control, relapse-free survival, or distant metastases between LDR and HDR patients. For Stage IB and II HDR patients, the pelvic control rates were 85% and 80% with survival rates of 86% and 65% at 3 years, respectively. In the LDR group, Stage IB and II patients had 91% and 78% pelvic control rates, with 82% and 58% survival rates at 3 years, respectively. No difference was seen in survival or pelvic control for bulky Stage I and II patients combined (> 5 cm). Pelvic control at 3 years was 44% (HDR) versus 75% (LDR) for Stage IIIB patients (p = 0.002). This difference in pelvic control was associated with a lower survival rate in the Stage IIIB HDR versus LDR population (33% versus 58%, p = 0.004). The only major difference, with regard to patient characteristics, between the Stage IIIB patients was the incidence of hydronephrosis in the HDR vs. LDR group—28% vs. 12%, respectively (p = 0.05). For Stage IIIB patients treated with HDR, our analysis suggested that pelvic control rates improved when the first brachytherapy insertion was performed after the majority of external beam radiotherapy had been delivered.

Conclusion: Similar outcome was observed for Stage IB and II patients treated with either HDR or LDR brachytherapy—regardless of tumor volume. However, poorer survival and pelvic control rates were observed for Stage IIIB patients treated with HDR brachytherapy. If HDR is used for Stage IIIB patients, our results suggest the majority of external beam radiotherapy should be delivered prior to initiating the brachytherapy to allow for adequate tumor regression. HDR brachytherapy is more convenient for patients, decreases the radiation exposure for health care workers, and should be considered a standard therapy for women with Stage I or II cervical cancer.     

宫颈癌低剂量率后装腔内放射治疗的远期疗效

目的 评价Gynatron低剂量率后装腔内治疗机的疗效。方法 总结1980年4月－1986年6月间,应用Gynatron后装机配合^60Co治疗机进行根治性放疗的136例宫颈癌,并与镭疗及高剂量率腔内后装治疗进行比较分析。结果 除5例失访外,全部患者随访超过15年,随访率96.3%（131／136）。Ⅱ、Ⅲ期的10年生存率分别为83.9%和43.2%。总10年生存率为63.5%。放射性直肠炎发生率为12.5%（17／136）,放射性膀胱炎发生率9.6%（13／136）。结论 Gynatron低剂量率后装腔内治疗系统虽然有一定局限性,但仍可获得较满意的疗效;其治疗并发症患者可以接受,放射性直肠炎、放射性膀胱炎发生率高于镭疗,低于高剂量率腔内后装放疗。     

高剂量率^192铱后装机腔内加外照射治疗宫颈癌60例临床分析

目的：探讨高剂量率^192铱后装腔内加体外照射治疗宫颈癌的疗效及副作用等。方法：2005年3月至2007年1月本院放疗中心共60例宫颈癌患者,采用8MV-X线直线加速器全盆照射,开始体外全盆腔照射,5次/周,2Gy/次,剂量25-40Gy;然后中间挡铅,4个野照射,5次/周,2Gy/次,宫旁剂量20-25Gy：同时腔内治疗,1次/周,6Gy/次,剂量为35-40Gy。腔内治疗采用ZL-HDR18铱高剂量率后装治疗机,全部病例均宫颈阴道同时进行。腔内治疗每周1次,A点剂量36-40GY/6-7F/6-7w,腔内治疗当日停体外照射,治疗时间56-77天。结果：CR＋PR 100%,随访超过3年,随访率达95%,3年生存率Ⅱ期88.3%,Ⅲ期82.9%;早期放射性直肠反应发生率为12.4%,膀胱反应发生率5.2%;晚期放射性直肠炎发生率13.8%,膀胱炎3.8%。结论：高剂量率^192铱后装机腔内加体外治疗宫颈癌的疗效满意,患者生存率较高,耐受好,并发症少。     

Role of interstitial brachytherapy in the treatment of malignant disease.

Interstitial brachytherapy was first applied using radium needles, with minimum protection of physicians and nurses. Modern techniques involve the use of radionuclide (192)Ir as the source used in computer-controlled remote afterloading machines, which can deliver a high dose rate (HDR). Treatment planning is also undertaken with the use of computers and anatomical cross-section images using CT, ultrasound and MRI. This review presents these modern techniques for tumors of a series of body sites: prostate, head and neck, breast, bladder, brain, and for soft-tissue sarcomas. Low dose rate (LDR) interstitial brachytherapy techniques are also included in this review since in some body sites there is a choice between HDR and LDR.     

Current controversies in high-dose-rate versus low-dose-rate brachytherapy for cervical cancer

The use of brachytherapy in the treatment of cervical cancer has increased worldwide since its initial introduction over 100 years ago. However, certain aspects of the use of high-dose-rate (HDR) versus low-dose-rate (LDR) brachytherapy continue to be controversial, particularly the role of HDR in FIGO Stage III cervical cancer and the use of HDR with concurrent chemotherapy. This study represents a systematic literature review of prospective and retrospective series of patients with cervical carcinoma treated with external-beam radiation (EBRT) followed by either HDR or LDR radiation. The local control rates, survival rates, and treatment-related complications in patients with Stage III cervical cancer treated with HDR or LDR and those treated with concomitant chemotherapy are examined. Patients with Stage III cervical cancer treated with EBRT and brachytherapy have a local control rate of >50% in most series. Randomized prospective and retrospective studies show overall statistically equivalent local control, overall survival, and complication rates between HDR and LDR. However, LDR may be preferable for large, bulky tumors at the time of brachytherapy. Retrospective studies of HDR and concurrent chemotherapy are limited but have demonstrated toxicity rates similar to those with LDR. Selected patients with Stage III cervical carcinoma who have an adequate response to EBRT and concomitant chemotherapy may be treated with HDR brachytherapy. The existing literature shows no significant increase in complications in patients treated with HDR and concurrent chemotherapy; however, sufficient tumor shrinkage prior to HDR and careful monitoring of the dose to the normal tissues are imperative.     

宫颈癌高低剂量率^137铯腔内后装放疗的比较

回顾性分析高剂量率（HDR）和低剂量率（LDR）腔内后装治疗宫颈癌。LDR组采用我院1979年6月～1984年12月137铯腔内后装放射治疗子宫颈癌862例。HDR组采用我院1986年12月至1987年7月137铯腔内后装治疗宫颈癌135例。结果：5年存活率HDR组低於LDR组；Ⅱ级放射性直肠炎HDR组为13．0％，低於LDR组22．6％（P＜0．01）。两组Ⅱ、Ⅲ期患者中无癌存活5年以上者宫旁A点吸收剂量比值（HDR／LDR）为0．53～0．54。结论：此剂量率转换系数对指导临床实践有参考价值。     

The American Brachytherapy Society recommendations for high-dose-rate brachytherapy for carcinoma of the cervix

PURPOSE: This report presents guidelines for using high-dose-rate (HDR) brachytherapy in the management of patients with cervical cancer, taking into consideration the current availability of resources in most institutions. METHODS: Members of the American Brachytherapy Society (ABS) with expertise in HDR brachytherapy for cervical cancer performed a literature review, supplemented their clinical experience to formulate guidelines for HDR brachytherapy of cervical cancer. RESULTS: The ABS strongly recommends that definitive irradiation for cervical carcinoma must include brachytherapy as a component. Each institution should follow a consistent treatment policy when performing HDR brachytherapy, including complete documentation of treatment parameters and correlation with clinical outcome, such as pelvic control, survival, and complications. The goals are to treat Point A to at least a total low-dose-rate (LDR) equivalent of 80-85 Gy for early stage disease and 85-90 Gy for advanced stage. The pelvic sidewall dose recommendations are 50-55 Gy for early lesions and 55-65 Gy for advanced ones. The relative doses given by external beam radiation therapy (EBRT) vs. brachytherapy depend upon the initial volume of disease, the ability to displace the bladder and rectum, the degree of tumor regression during pelvic irradiation, and institutional preference. As with LDR brachytherapy, every attempt should be made to keep the bladder and rectal doses below 80 Gy and 75 Gy LDR equivalent doses, respectively. Interstitial brachytherapy should be considered for patients with disease that cannot be optimally encompassed by intracavitary brachytherapy. While recognizing that many efficacious HDR fractionation schedules exist, some suggested dose and fractionation schemes for combining the EBRT with HDR brachytherapy for each stage of disease are presented. These recommendations are intended only as guidelines, and the suggested fractionation schemes have not been thoroughly tested. The responsibility for the medical decisions ultimately rests with the treating radiation oncologist. CONCLUSION: Guidelines are established for HDR brachytherapy for cervical cancer. Practitioners and cooperative groups are encouraged to use these guidelines to formulate their treatment and dose-reporting policies. These guidelines will be modified, as image-based treatment becomes more widely available.     

Phase III randomized trial comparing LDR and HDR brachytherapy in treatment of cervical carcinoma

PURPOSE: Intracavitary brachytherapy plays an important role in the treatment of cervical carcinoma. Previous results have shown controversy between the effect of dose rate on tumor control and the occurrence of complications. We performed a prospective randomized clinical trial to compare the clinical outcomes between low-dose-rate (LDR) and high-dose-rate (HDR) intracavitary brachytherapy for treatment of invasive uterine cervical carcinoma. METHODS AND MATERIALS: A total of 237 patients with previously untreated invasive carcinoma of the uterine cervix treated at King Chulalongkorn Memorial Hospital were randomized between June 1995 and December 2001. Excluding ineligible, incomplete treatment, and incomplete data patients, 109 and 112 patients were in the LDR and HDR groups, respectively. All patients were treated with external beam radiotherapy and LDR or HDR intracavitary brachytherapy using the Chulalongkorn treatment schedule. RESULTS: The median follow-up for the LDR and HDR groups was 40.2 and 37.2 months, respectively. The actuarial 3-year overall and relapse-free survival rate for all patients was 69.6% and 70%, respectively. The 3-year overall survival rate in the LDR and HDR groups was 70.9% and 68.4% (p = 0.75) and the 3-year pelvic control rate was 89.1% and 86.4% (p = 0.51), respectively. The 3-year relapse-free survival rate in both groups was 69.9% (p = 0.35). Most recurrences were distant metastases, especially in Stage IIB and IIIB patients. Grade 3 and 4 complications were found in 2.8% and 7.1% of the LDR and HDR groups (p = 0.23). CONCLUSION: Comparable outcomes were demonstrated between LDR and HDR intracavitary brachytherapy. Concerning patient convenience, the lower number of medical personnel needed, and decreased radiation to health care workers, HDR intracavitary brachytherapy is an alternative to conventional LDR brachytherapy. The high number of distant failure suggests that other modalities such as systemic concurrent or adjuvant chemotherapy might lower this high recurrence, especially in Stage IIB and IIIB.     

High dose rate brachytherapy in the treatment of prostate cancer.

Because the HDR brachytherapy treatments are delivered within minutes and on an outpatient basis, HDR brachytherapy is very well tolerated by patients and offers complete radiation safety. Published studies2, 11, 12, 13, 16, 17, 18, 22, 24, 25 have shown high local clinical and biochemical control rates. Chronic complications have been acceptably low. Very low rates of urinary incontinence and high sexual potency rates have been reported. Gastrointestinal morbidity has been minimal. The development of Ir-192 HDR afterloading brachytherapy and refinements in the dosimetry have ushered in a new era in prostate brachytherapy. The control of the radiation dose and the ability to shape the radiation treatment envelope using a stepping source have allowed a giant step forward in radiation oncology technology. It is now possible to deliver tumoricidal doses of radiation conformally to the prostate while minimizing the dose to the bladder, urethra, and rectum. At present, HDR afterloaded brachytherapy is the optimal whole-organ and tumor-specific conformal radiation therapy for prostate cancer.