Endoluminal and Interstitial Brachytherapy for the Treatment of Gastrointestinal Malignancies: a Systematic Review

Radiation therapy is an integral component in the multimodality management of many gastrointestinal (GI) cancers at all stages of clinical presentation. With recent advances in technology and radiation delivery, external beam radiation therapy (EBRT) can be delivered with reduced toxicity. However, despite these advances, EBRT doses are still limited by the presence of radiosensitive serial structures near clinical targets in the GI tract. Relative to EBRT techniques, brachytherapy techniques have a lower integral dose and more rapid fall-off, allowing for high-dose delivery with little normal tissue exposure. Given the unique characteristics of brachytherapy, it is an attractive strategy to treat GI malignancies. This review addresses the application of both high-dose rate brachytherapy (HDRBT) and low-dose rate brachytherapy (LDRBT) to multiple GI malignancies for both definitive and palliative management.     

The role of external-beam radiation therapy in the treatment of clinically localized prostate cancer.

BACKGROUND: The treatment of clinically localized prostate cancer is controversial. Options include radical prostatectomy, external-beam radiation therapy (EBRT), brachytherapy, cryotherapy, and watchful waiting. METHODS: The author reviews EBRT as treatment for clinically localized prostate cancer, with particular emphasis on the technological advances that have allowed dose escalation and fewer therapy-related side effects. RESULTS: Technological advances in the last two decades have significantly improved the delivery of EBRT to the prostate. This has resulted in an overall increase in the total dose that can be safely delivered to the prostate, which has led to modest improvements in biochemical outcome. An alternative approach of combining androgen suppression therapy and EBRT has also been successful in improving clinical outcomes. However, establishing the optimal therapy for prostate cancer remains controversial. CONCLUSIONS: Recent progress has led to improvements in clinical outcomes in patients treated with EBRT for prostate cancer. It is hoped that the next decades will bring continued advances in the development of biologicals that will further improve current clinical outcomes.     

Conventional radiation therapy of cervical cancer

This review of the present literature about the conventional management of patients with definitive radiotherapy for invasive carcinoma of the cervix will focus on advances in the use of external-beam radiation therapy (EBRT) as well as in the administration of low-dose-rate brachytherapy for the delivery of radiotherapy. Important concepts discussed include: techniques and dose fractionation for EBRT; newer imaging modalities for administration of EBRT; construction of the midline shield for external irradiation of the pelvic nodes following brachytherapy; the role of elective para-aortic nodal external radiotherapy; and the adequate number of brachytherapy applications needed to impact on patient outcome. Considerable attention will be given to multi-institutional clinical data (e.g., the Patterns of Care Study and the Radiation Therapy Oncology Group) to illustrate advances in radiotherapy of patients with cervical carcinoma.     

Acute genitourinary toxicity after high-dose-rate (HDR) brachytherapy combined with hypofractionated external-beam radiation therapy for localized prostate cancer: correlation between the urethral dose in HDR brachytherapy and the severity of acute genitourinary toxicity

PURPOSE: Several investigations have revealed that the alpha/beta ratio for prostate cancer is atypically low, and that hypofractionation or high-dose-rate (HDR) brachytherapy regimens using appropriate radiation doses may be expected to yield tumor control and late sequelae rates that are better or at least as favorable as those achieved with conventional radiation therapy. In this setting, we attempted treating localized prostate cancer patients with HDR brachytherapy combined with hypofractionated external beam radiation therapy (EBRT). The purpose of this study was to evaluate the feasibility of using this approach, with special emphasis on the relationship between the severity of acute genitourinary (GU) toxicity and the urethral dose calculated from the dose-volume histogram (DVH) of HDR brachytherapy. METHODS AND MATERIALS: Between September 2000 and December 2003, 70 patients with localized prostate cancer were treated by iridium-192 HDR brachytherapy combined with hypofractionated EBRT at the Gunma University Hospital. Hypofractionated EBRT was administered in fraction doses of 3 Gy, three times per week; a total dose of 51 Gy was delivered to the prostate gland and the seminal vesicles using the four-field technique. No elective pelvic irradiation was performed. After the completion of EBRT, all the patients additionally received transrectal ultrasonography (TRUS)-guided HDR brachytherapy. The fraction size and the number of fractions in HDR brachytherapy were prospectively changed, whereas the total radiation dose for EBRT was fixed at 51 Gy. The fractionation in HDR brachytherapy was as follows: 5 Gy x 5, 7 Gy x 3, 9 Gy x 2, administered twice per day, although the biologic effective dose (BED) for HDR brachytherapy combined with EBRT, assuming that the alpha/beta ratio is 3, was almost equal to 138 in each fractionation group. The planning target volume was defined as the prostate gland with 5-mm margin all around, and the planning was conducted based on computed tomography images. The number of patients in each fractionation group was as follows: 13 in the 5-Gy group; 19 in the 7-Gy group, and 38 in the 9-Gy group. The tumor stage was T1 in 10 patients, T2 in 36 patients, and T3 in 24 patients. The Gleason score was 2-6 in 11 patients, 7 in 34 patients, and 8-10 in 25 patients. Androgen ablation was performed in all the patients. The median follow-up duration was 14 months (range 3-42 months). The toxicities were graded based on the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer toxicity criteria. RESULTS: The main symptoms of acute GU toxicity were dysuria and increase in urinary frequency or nocturia. The grade distribution of acute GU toxicity in the patients was as follows: Grade 0-1, 39 patients (56%), and Grade 2-4, 31 patients (44%). One patient who developed acute urinary obstruction was classified as having Grade 4 toxicity. Comparison of the distribution of the grade of acute GU toxicity among the different fractionation groups revealed no statistically significant differences among the groups. The urethral dose in HDR brachytherapy was evaluated using the following DVH parameters: V30 (percentage of the urethral volume receiving 30% of the prescribed radiation dose), V80, V90, V100, V110, V120, V130, and V150. The V30-110 values in the patients with Grade 2-4 acute GU toxicity were significantly higher than those in patients with Grade 0-1 toxicity. On the other hand, there were no significant differences in the V120-150 values between patients with Grade 0-1 and Grade 2-4 toxicity. Regarding the influence of the number of needles implanted for the radiation therapy, patients with 11 needles or less showed a significantly higher incidence of Grade 2-4 acute GU toxicity compared with those with 12 needles or more (p < 0.05). CONCLUSIONS: It was concluded that HDR brachytherapy combined with hypofractionated EBRT is feasible for localized prostate cancer when considered from the viewpoint of acute toxicity. Increase in the fraction dose or reduction in the number of fractions in HDR brachytherapy did not affect the severity of acute GU toxicity, and the volume of urethra receiving an equal or lower radiation dose than the prescribed dose was more closely associated with the grade severity of acute GU toxicity than that receiving a higher than the prescribed dose.     

Advances in Radiation Oncology for the Treatment of Cervical Cancer

Background: Over the past two decades, there has been significant advancement in the management of cervical cancer, particularly in the domain of definitive chemoradiotherapy for locally advanced cervical cancer (LACC). Indeed, radiation treatment paradigms have shifted from a two-dimensional (2D) approach solely based on anatomical bony landmarks, to an image-guided three-dimensional (3D) approach, with the goal of delivering doses more precisely to clinical targets with an increased sparing of organs-at-risk. Methods: This is a narrative review on the advances in radiation technologies for the treatment of cervical cancer. Using the PubMed database, we identified articles published in English up until November 18, 2021 on the treatment of LACC with external beam radiotherapy (EBRT) and brachytherapy. A search of the Clinicaltrials.gov and Clinicaltrialsregister.eu retrieved information on ongoing clinical trials on the topic of combined immunotherapy and radiotherapy in cervical cancer. Results: We highlight the historical evolution from the use of 2D radiotherapy to 3D-conformal radiotherapy, and then intensity modulated radiotherapy (IMRT) for the delivery of EBRT. We also discuss advances in brachytherapy, notably the transition to 3D image-guided adaptive brachytherapy (3D-IGABT). In this context, we highlight large cohort studies that were recently constructed and have shown significant improvement in local control and treatment-related toxicities with 3D-IGABT. Finally, we discuss other advances in the field, notably the use of stereotactic body radiotherapy (SBRT) as a substitute to brachytherapy, and the addition of immunotherapy to chemoradiation. Conclusions: The use of IG-IMRT and 3D-IGABT have considerably improved treatment outcomes and toxicity profiles for patients with LACC, and are now considered the gold standard in many countries. The use of SBRT boost as a replacement for brachytherapy has been associated with increased toxicity and decreased efficacy and should be used with caution in the context of clinical trials. New experimental approaches include the addition of immunotherapy to chemoradiation regimens.     

Technology Insight: Combined external-beam radiation therapy and brachytherapy in the management of prostate cancer

External-beam radiation therapy (EBRT) combined with brachytherapy is an attractive treatment option for selected patients with clinically localized prostate cancer. This therapeutic strategy offers dosimetric coverage if local-regional microscopic disease is present and provides a highly conformal boost of radiation to the prostate and immediate surrounding tissues. Either low-dose-rate (LDR) permanent brachytherapy or high-dose-rate (HDR) temporary brachytherapy can be combined with EBRT; such combined-modality therapy (CMT) is typically used to treat patients with intermediate-risk to high-risk, clinically localized disease. Controversy persists with regard to indications for CMT, choice of LDR or HDR boost, isotope selection for LDR, and integration of EBRT and brachytherapy. Initial findings from prospective, multicenter trials of CMT support the feasibility of this strategy. Updated results from these trials as well as those of ongoing and new phase III trials should help to define the role of CMT in the management of prostate cancer. In the meantime, long-term expectations for outcomes of CMT are based largely on the experience of single institutions, which demonstrate that CMT with EBRT and either LDR or HDR brachytherapy can provide freedom from disease recurrence with acceptable toxicity.     

Acute genitourinary toxicity after high dose rate (HDR) brachytherapy combined with hypofractionated external-beam radiation therapy for localized prostate cancer: Second analysis to determine the correlation between the urethral dose in HDR brachytherapy and the severity of acute genitourinary toxicity

PURPOSE: We have been treating localized prostate cancer with high-dose-rate (HDR) brachytherapy combined with hypofractionated external beam radiation therapy (EBRT) at our institution. We recently reported the existence of a correlation between the severity of acute genitourinary (GU) toxicity and the urethral radiation dose in HDR brachytherapy by using different fractionation schema. The purpose of this study was to evaluate the role of the urethral dose in the development of acute GU toxicity more closely than in previous studies. For this purpose, we conducted an analysis of patients who had undergone HDR brachytherapy with a fixed fractionation schema combined with hypofractionated EBRT. METHODS AND MATERIALS: Among the patients with localized prostate cancer who were treated by 192-iridium HDR brachytherapy combined with hypofractionated EBRT at Gunma University Hospital between August 2000 and November 2004, we analyzed 67 patients who were treated by HDR brachytherapy with the fractionation schema of 9 Gy x two times combined with hypofractionated EBRT. Hypofractionated EBRT was administered at a fraction dose of 3 Gy three times weekly, and a total dose of 51 Gy was delivered to the prostate gland and seminal vesicles using the four-field technique. No elective pelvic irradiation was performed. After the completion of EBRT, all the patients additionally received transrectal ultrasonography-guided HDR brachytherapy. The planning target volume was defined as the prostate gland with a 5-mm margin all around, and the planning was conducted based on computed tomography images. The tumor stage was T1c in 13 patients, T2 in 31 patients, and T3 in 23 patients. The Gleason score was 2-6 in 12 patients, 7 in 34 patients, and 8-10 in 21 patients. Androgen ablation was performed in all the patients. The median follow-up duration was 11 months (range 3-24 months). The toxicities were graded based on the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer toxicity criteria. RESULTS: The main symptoms of acute GU toxicity were dysuria and increase in the urinary frequency or nocturia. The grade distribution of acute GU toxicity in the patients was as follows: Grade 0-1, 42 patients (63%); Grade 2-3, 25 patients (37%). The urethral dose in HDR brachytherapy was determined using the following dose-volume histogram (DVH) parameters: V30 (percentage of the urethral volume receiving 30% of the prescribed radiation dose), V80, V90, V100, V110, V120, V130, and V150. In addition, the D5 (dose covering 5% of the urethral volume), D10, D20, and D50 of the urethra were also estimated. The V30-V150 values in the patients with Grade 2-3 acute GU toxicity were significantly higher than those in patients with Grade 0-1 toxicity. The D10 and D20, but not D5 and D50, values were also significantly higher in the patients with Grade 2-3 acute GU toxicity than in those with Grade 0-1 toxicity. Regarding the influence of the number of needles implanted, there was no correlation between the number of needles implanted and the severity of acute GU toxicity or the V30-V150 values and D5-D50 values. CONCLUSIONS: It was concluded that HDR brachytherapy combined with hypofractionated EBRT is feasible for localized prostate cancer, when considered from the viewpoint of acute toxicity. However, because the urethral dose was closely associated with the grade of severity of the acute GU toxicity, the urethral dose in HDR brachytherapy must be kept low to reduce the severity of acute GU toxicity.     

High dose rate iridium-192 brachytherapy as a component of radical radiotherapy for the treatment of localised prostate cancer

AimsTo assess the treatment outcomes and toxicity of conformal high dose rate (HDR) brachytherapy boost as a means of radiation dose escalation in patients with localised prostate cancer.Materials and methodsBetween December 1998 and July 2004, 65 consecutive patients with localised prostate cancer (magnetic resonance imaging-staged T1–3 N0 M0) were treated with external beam radiation therapy (EBRT) followed by two fractions of HDR iridium-192 brachytherapy. The patients selected this treatment modality in preference to entering an ongoing randomised phase 3 trial. Any pre-treatment serum prostate-specific antigen (PSA) and Gleason score were included. The primary end point was biochemical disease-free progression. Late treatment-related morbidity was graded according to the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer criteria.ResultsThe median patient age was 67.3 years (range 47.9–80). Sixty patients (92.3%) had intermediate- to high-risk disease defined by clinical stage, presenting PSA and Gleason score/World Health Organisation (WHO) grade. With a median follow-up of 3.5 years (range 0.6–5.8), two patients had died of metastatic disease and another four patients had PSA relapse, giving a 3-year actuarial biochemical disease-free progression of 90.8%. Three patients (4.6%) had acute grade 3 genitourinary toxicity, in the form of urinary retention. Late grade 3 and 4 genitourinary toxicities occurred in four patients (6.2%) and one patient (1.5%), respectively. No late gastrointestinal toxicities were observed.ConclusionsThese results suggest that the combined modality of conformal HDR brachytherapy and EBRT is a feasible treatment modality with acceptable acute and late toxicities, comparable with those of EBRT alone. It offers an attractive conformal treatment modality with the potential of further dose escalation in the treatment of localised prostate cancer.     

Nouvelles techniques et bénéfices attendus pour la radiothérapie du cancer du poumon

Radiotherapy is used for inoperable lung cancers, sometimes in association with chemotherapy. Outcomes of conventional radiotherapy are disappointing. New techniques improve adaptation to tumour volume, decrease normal tissue irradiation and lead to increasing tumour dose with the opportunity for improved survival. With intensity-modulated radiation therapy, isodoses can conform to complex volumes. It is widely used and seems to be indicated in locally advanced stages. Its dosimetric improvements have been demonstrated but outcomes are still heterogeneous. Stereotactic radiotherapy allows treatment of small volumes with many narrow beams. Dedicated devices or appropriate equipment on classical devices are needed. In early stages, its efficacy is comparable to surgery with an acceptable toxicity. Endobronchial brachytherapy could be used for early stages with specific criteria. Hadrontherapy is still experimental regarding lung cancer. Hadrons have physical properties leading to very accurate dose distribution. In the rare published studies, toxicities are roughly lower than others techniques but for early stages its effectiveness is not better than stereotactic radiotherapy. These techniques are optimized by metabolic imaging which precisely defines the target volume and assesses the therapeutic response; image-guided radiation therapy which allows a more accurate patient set up and by respiratory tracking or gating which takes account of tumour respiratory motions.     

3D conformal HDR brachytherapy and external beam irradiation combined with temporary androgen deprivation in the treatment of localized prostate cancer.

PURPOSE: To evaluate treatment outcome of 3D conformal high dose rate (HDR) brachytherapy and external beam irradiation (EBRT) combined with temporary androgen deprivation for patients with localized prostate cancer. PATIENTS AND METHODS: Between January 1997 and September 1999 we treated 102 patients with stage T1-3 N0 M0 prostate cancer. Stage T1-2 was found in 71, T3 in 31 patients. Median pretreatment PSA level was 15.3 ng/ml. After ultrasound-guided transrectal implantation of four afterloading needles, CT based 3D brachytherapy planning was performed. All patients received four HDR implants using a reference dose per implant of 5 or 7Gy. Time between each implant was 14 days. After brachytherapy EBRT followed up to 39.6 or 45.0 Gy. All patients received temporary androgen deprivation, starting 2-19 months before brachytherapy, ending 3 months after EBRT. RESULTS: Median follow-up was 2.6 years (range 2.0-4.1 years). Actuarial biochemical control rate was 87% at 2 years and 82% at 3 years. In 14 patients we noted biochemical failure, in five patients clinical failure. Overall survival was 90%, disease specific survival 98.0% at 3 years. Acute grade 3 toxicity occurred in 4%, late grade 3 toxicity in 5%. One patient developed a prostatourethral-rectal fistula as late grade 4 toxicity. The conformal quality of 300 HDR implants was analyzed using dose volume histograms. CONCLUSIONS: 3D conformal HDR brachytherapy and EBRT combined with temporary androgen deprivation is an effective treatment modality for prostate cancer with minimal associated toxicity and encouraging biochemical control rates after a median follow-up of 2.6 years.     

Comparing dosimetric and cancer control outcomes after intensity-modulated radiation therapy and tomotherapy for advanced cervical cancer

Concurrent chemoradiation therapy (CCRT) is the standard treatment for locally advanced cervical cancer. The present study aimed to compare the therapeutic responses, toxicities and dosimetric parameters between intensity-modulated radiation therapy (IMRT) and tomotherapy (TOMO) in patients with advanced cervical cancer. This retrospective study included 310 patients with stage IIB-IIIB cervical cancer who underwent CCRT, with 155 patients in each group. Intracavitary brachytherapy was performed after a course of external beam radiation therapy (EBRT), or in the last week of pelvic EBRT. The treatment planning aim at point A (defined as a reference location 2 cm above the vaginal fornix and 2 cm beside the mid axis of the uterus) was >85 Gy in an equivalent dose at 2 Gy. There was no statistical difference with regard to clinicopathological characteristics between the two groups (P>0.05). Improved dose conformity and dose homogeneity (P<0.05) were observed in TOMO planning. TOMO provided more efficacious critical organ sparing than IMRT when assessing the percentage of normal tissue receiving at least 20 Gy (V20) for the bladder, the percentage of normal tissue receiving at least 40 Gy (V40) for the femoral head, and the V40 and V20 for the rectum (P<0.05). TOMO demonstrated a greater ability to protect the ovary (P<0.05). The acute radiation toxicity of proctitis and leukopenia were significantly lower in the TOMO group (P<0.05). The chronic radiation toxicity of radiation enterocolitis and cystitis was lower in the TOMO group (P<0.05). Thus, TOMO provided better critical organ sparing than IMRT. The radiation toxicities were acceptable. Therefore, TOMO appears to be a good option for the treatment of stage IIB-IIIB cervical cancer.     

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。     

Integrating hormonal therapy with external-beam radiation and brachytherapy for prostate cancer

The use of hormonal therapy with external-beam radiation (EBRT) to treat prostate cancer is a topic that has been well explored. The potential use of hormonal therapy and brachytherapy in the treatment of prostate cancer, however, continues to be controversial. This review is based on our current interpretation of the available literature assessing the outcomes of patients treated with EBRT and brachytherapy with or without hormonal therapy. Extrapolating from the findings of the Radiation Therapy Oncology Group (RTOG) 9413 trial, there appears to be a favorable interaction between hormonal therapy and irradiation in the lymph nodes. The benefits demonstrated with whole-pelvic EBRT and hormonal therapy are likely to extend to patients treated with brachytherapy as well. Studies suggest that the role of hormonal therapy in brachytherapy is limited without the application of whole-pelvic EBRT due to the inability of brachytherapy to address potential lymph nodes at risk. The potential role of hormonal therapy in conjunction with brachytherapy without pelvic radiotherapy, is limited by inconclusive data and abbreviated follow-up times.     

High dose rate brachytherapy boost for prostate cancer: A systematic review

Studies of dose-escalated external beam radiation therapy (EBRT) and low dose rate brachytherapy (LDR-BT) have shown excellent rates of tumor control and cancer specific survival. Moreover, LDR-BT combined with EBRT (i.e. “LDR-BT boost”) is hypothesized to improve local control. While phase II trials with LDR-BT boost have produced mature data of outcomes and toxicities, high dose rate (HDR)-BT has been growing in popularity as an alternative boost therapy. Boost from HDR-BT has theoretical advantages over LDR-BT, including improved cancer cell death and better dose distribution from customization of catheter dwell times, locations, and inverse dose optimization. Freedom from biochemical failure rates at five years for low-, intermediate-, high-risk, and locally advanced patients have generally been 85–100%, 80–98%, 59–96%, and 34–85%, respectively. Late Radiation Therapy Oncology Group grade 3–4 toxicities have also been encouraging with <6% of patients experiencing any toxicity. Limitations of current HDR-BT boost studies include reports of only single-institution experiences, and unrefined reports of toxicity or patient quality of life. Comparative effectiveness research will help guide clinicians in selecting the most appropriate treatment option for individual patients based on risk-stratification, expected outcomes, toxicities, quality of life, and cost.     

High dose rate interstitial brachytherapy in soft tissue sarcoma: technical aspects and results.

BACKGROUND: Radiation is essential for function preservation in the management of soft tissue sarcoma (STS). One of the advantages of brachytherapy is that it allows for specific localization of radiation dose to the tumor bed. We examined the results of our clinical experiences with immediate postoperative high dose rate (HDR) brachytherapy and external beam radiation treatment (EBRT) for STS. METHODS: A total of 17 patients (11 primary and six recurrent) between 1995 and 1999 were included in this review. The inclusion criteria for HDR and EBRT were as follows: (1) high-grade tumor, (2) low-grade tumor of > or = 10 cm, (3) recurrent tumor, (4) tumor abutting or invading critical structures and (5) positive margin. The catheters (six French) were placed parallel to the long axis of the tumor with a 1-1.5 cm spacing in between. If necessary, muscle or gel-foam was placed over the critical structures to maintain a minimum space of 0.5 cm from the catheters. On postoperative day 6, patients received HDR (2-3 Gy/fraction x6, twice daily). Three weeks later, patients received EBRT (total 36-60 Gy). The follow-up duration was between 13 and 60 months (median 31 months). RESULTS: There was no local failure within the radiation field in any of the patients. One patient required wound revision for delayed healing after brachytherapy. During EBRT, most patients experienced only mild erythema (grade 1 or 2 skin reaction). In long-term follow-up, there were no patients with neuropathy or significant fibrosis. CONCLUSIONS: Our results suggest that immediate postoperative HDR with a total dose of 12-18 Gy over 3 days is an effective treatment combined with EBRT in the management of STS.     

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。     

Current status and perspectives of brachytherapy for prostate cancer

Permanent implant brachytherapy (PIB) for prostate cancer in a modern style was introduced in the 1980s. With the excellent outcome, the method prevailed rapidly in the United States in the 1990s, and it has become a standard treatment option at least for low-risk prostate cancer today. In Japan, PIB using ¹²⁵I free seeds was started in 2003, and it is being rapidly accepted. About 90 institutions in Japan have already started PIB, and about 10 000 patients have received this treatment during these 5 years. The outcome data for Japanese men should be established, and the efficacy of the combined use of external beam radiation therapy (EBRT) and hormone therapy should be examined. High-dose-rate (HDR) brachytherapy, which has many advantages over PIB, was started in the 1980s, firstly as a boost combined with EBRT, in Europe and the United States. In Japan, combined HDR brachytherapy and EBRT therapy was started in 1994. As for monotherapeutic HDR brachytherapy, the first series in the world was initiated in Osaka, Japan, in 1995. HDR brachytherapy, both as monotherapy and as combined therapy with EBRT, is yielding promising outcomes, and the study of these modalities should be continued. Mutual understanding and cooperation among urologists, radiation oncologists, and medical physicists is essential to enhance brachytherapy for prostate cancer.     

HDR brachytherapy for anal cancer

The challenge of treating anal cancer is to preserve the anal sphincter function while giving high doses to the tumor and sparing the organ at risk. For that reason there has been a shift from radical surgical treatment with colostomy to conservative treatment. Radiotherapy combined with chemotherapy has an important role in the treatment of anal cancer patients. New techniques as intensity modulated radiotherapy (IMRT) have shown reduced acute toxicity and high rates of local control in combination with chemotherapy compared to conventional 3-D radiotherapy. Not only external beam radio-chemotherapy treatment (EBRT) is an established method for primary treatment of anal cancer, brachytherapy (BT) is also an approved method. BT is well known for boost irradiation in combination with EBRT (+/– chemotherapy). Because of technical developments like modern image based 3D treatment planning and the possibility of intensity modulation in brachytherapy (IMBT), BT today has even more therapeutic potential than it had in the era of linear sources. The combination of external beam radiotherapy (EBRT) and BT allows the clinician to deliver higher doses to the tumor and to reduce dose to the normal issue. Improvements in local control and reductions in toxicity therefore become possible. Various BT techniques and their results are discussed in this work.     

Standardization and Quality Assurance of Radiation Therapy Volumes for Adults With High-Grade Gliomas

Standard treatment for Glioblastoma Multiforme (GBM) consists of a combination of chemotherapy and radiation therapy followed by adjuvant chemotherapy. While the optimal dose of radiation therapy has been established, significant variability in volume of tissue irradiated exists. In this article we review the current guidelines, patterns of care, patterns of failure, imaging advances and toxicity related to radiation therapy volumes in the treatment of GBM.