High-dose-rate interstitial brachytherapy for vaginal endometrial cancer recurrence after prior surgery and radiotherapy

PurposeCharacterize the clinical outcomes of endometrial cancer vaginal recurrences after previous surgery and radiation therapy treated with reirradiation including image-guided interstitial high-dose-rate (HDR) brachytherapy.Methods and materialsA single-institution retrospective study identifying women receiving reirradiation for vaginal recurrence of endometrial cancer between 2004 and 2017.ResultsTwenty-three women had vaginal recurrences of endometrial cancer, median 13.7 months (range 3.5–104.9) from initial radiation. All received reirradiation with interstitial HDR brachytherapy, and seven also received external beam radiation. Median reirradiation EQD2_10 was 48 Gy (range 24.0–68.81), and median cumulative EQD2_10 was 106.25 Gy (range 62.26–122.0). Median follow-up after reirradiation was 40.2 months (range 4.5–112.7). At 3 years, overall survival was 56%, cancer-specific survival was 61%, and disease-free survival was 46%. 14 patients experienced disease recurrence; 10 including distant sites, one at a regional node only. Three patients experienced local recurrences, two of whom did not complete the prescribed course of reirradiation. The overall crude local control rate was 87%. Three patients experienced Grade 3 vaginal toxicity. There was no bladder or rectal toxicity with Grade >2.ConclusionsReirradiation including interstitial HDR brachytherapy is a promising option for vaginal recurrences of endometrial cancer after prior radiation, with high rate of local control and acceptable toxicity. However, distant failure is common. Further studies are needed to determine cumulative radiation dose limits and the role of systemic therapy in this scenario.     

Salvagebehandlung fortgeschrittener Plattenepithelkarzinome der Mundhöhle und des Oropharynx

Purpose

The clinical effect of high-dose-rate (HDR) interstitial brachytherapy combined with tumor resection was investigated in this retrospective study on patients with recurrent oral and oropharyngeal squamous cell carcinoma.

Patients and Methods

Oral and oropharyngeal squamous cell carcinoma in 38 patients were treated over a period of 7 years (1988–1994) by HDR interstitial brachytherapy using Gammamed 12i^® equipment. Pretreatment of patients in terms of irradiation and surgery differed (33 irradiated with a total dose between 60.0 and 75.6 Gy, including 8 patients with additional surgery; 1 patient with surgery alone, and 4 patients without any pretreatment). Indications for interstitial brachytherapy differed according to individual responses to treatment and medical histories.

Results

Interstitial brachytherapy was successful in the majority of patients, i. e. complete remission: 12, partial remission: 19, no change: 2, progression: 5. Local control and overall survival including patients with surgical treatment was 59% and 81% at 6 months and 47% and 49% after 12 months, respectively.

Conclusion

Interstitial HDR brachytherapy with Iridium 192 is recommended in patients with local recurrences or second primary carcinomas after previous external radiotherapy in the head and neck region. Combination of interstitial brachytherapy and surgery is preferable for these patients.     

High-dose-rate interstitial brachytherapy for gynecologic malignancies

PURPOSE: The study aimed to assess the outcome of locally advanced cervical and vaginal cancer treated with high-dose-rate interstitial brachytherapy (HDRB). METHODS AND MATERIALS: Between 1998 and 2004, 16 previously unirradiated patients with locally advanced cervical and vaginal cancer not suitable for intracavitary brachytherapy because of distorted anatomy or extensive vaginal disease were treated with HDRB in combination with external beam radiotherapy. All patients received whole pelvis external beam radiation therapy (EBRT) followed by interstitial implantation. The median whole pelvis external beam dose was 45 Gy (range, 39.6-50.4 Gy) with 11 patients receiving parametrial boost to a median dose of 9 Gy. Twelve (75%) of these patients received chemotherapy concurrent with external beam. All patients received a single HDRB procedure using a modified Syed-Neblett template. A CT scan was performed postimplant for needle placement verification and treatment planning purpose. Dose was prescribed to the tumor volume based on the radiographic and clinical examination. All patients received 18.75 Gy in five fractions delivered twice daily. The median followup was 25 months (6-69 months). RESULTS: Median cumulative biologic effective dose (EBRT+HDRB) to tumor volume was 78.9 Gy10 with the range of 72.5-85.2Gy10. Median cumulative biologic effective dose for the rectum and bladder were 99.4 Gy3 (range, 79.6-107.8 Gy3) and 96.4 Gy3 (range, 78.3-105.3 Gy3), respectively. Complete response was achieved in 13 (81%) patients with 3 patients having persistent disease. Five of these 13 patients developed recurrence at a median time of 14 months (distant in 4 and local and distant in 1). The 5-year actuarial local control and cause-specific survival were 75% and 64%, respectively. In subset analysis, 5-year actuarial local control was 63% for cervical cancer patients and 100% for vaginal cancer patients. No patient had acute Grade 3 or 4 morbidity. Grade 3 or 4 delayed morbidity resulting from treatment occurred in 1 patient with 5-year actuarial rate of 7%. Three patients had late Grade 2 rectal morbidity and 1 patient had Grade 2 small bowel morbidity. CONCLUSIONS: Our series suggests that single interstitial implantation procedure with five fractions of 3.75 Gy each to target volume is an effective and safe fractionation schedule. The integration of imaging modality helps in decreasing dose to the critical organs. Additional patients and followup are ongoing to determine the long-term efficacy of this approach.     

The addition of interstitial needles to intracavitary applicators in the treatment of locally advanced cervical cancer: Why is this important and how to implement in low- and middle-income countries?

PurposeCervical cancer is the leading cause of cancer mortality of women in low-/middle-income countries. Interstitial needles improve outcomes but require resources beyond those available in endemic regions. We conducted a retrospective review of the use of interstitial needles in locally advanced cervical cancer and simulated both 3D planning without needles and 2D planning to explore the benefit of interstitial needles.Methods and Materials57 brachytherapy plans of 17 patients who had intracavitary tandem and ring plus interstitial brachytherapy were reviewed. Prescribed dose was 7 Gy × four fractions. 2D plans prescribed to point A were generated to represent a standard Manchester loading. Dosimetric outcomes to clinical target volume and organs at risk (OARs) were compared with those of 3D-based plans.ResultsHigh-risk clinical target volume coverage was excellent: 93.2% for 2D plans, 93.9% for 3D plans without needles, and 96.2% for 3D with needles. The mean dose to 90% of target was 8.5 Gy/fraction for 2D plans, 7.5 for 3D without needles, and 7.9 Gy/fraction for 3D with needles. However, the 2D plans delivered 12% above recommended dose constraints for OARs (except rectum). Dosimetric differences were found between 3D planning and 3D with needles for target coverage (p = 0.002). Dose to OARs was significantly lower when 3D plans with needles were compared with 2D plans.ConclusionsInterstitial needles provide an optimal therapeutic ratio for patients with high-volume disease or/and unfavorable topography. This justifies additional capital investment in resources for implementation to provide optimal treatment for locally advanced cervical cancer globally.     

CT-guided interstitial brachytherapy in the local treatment of extrahepatic, extrapulmonary secondary malignancies

The purpose was to evaluate the safety and efficacy of high-dose-rate (HDR) CT-guided interstitial brachytherapy in the treatment of extrahepatic, extrapulmonary, secondary malignancies. Nineteen patients were included in this prospective study. The median age was 66 years (49–77). Underlying primaries comprised colorectal carcinomas in six, renal cell carcinoma in three, pancreatic carcinoma in three, cervical cancer in two, endometrial cancer in two and NSCLC, breast cancer and sarcoma in one patient each. All patients had undergone extensive pretreatments. CT-guided HDR brachytherapy employed a ¹⁹²Iridium source. Dose planning for brachytherapy was performed using 3D CT data acquired after CT-guided percutaneous applicator positioning. MRI follow-up was performed 6 weeks and every 3 months post intervention. Primary endpoints were complications, local tumor control and progression-free survival. The median tumor diameter was 6 cm (2–15 cm). Tumor locations included the hepatoduodenal ligament, mesentery, adrenal gland, mesogastrium and local recurrences after rectal or pancreatic cancer. The minimal median dose in the target volume was 11 Gy (4–18 Gy). Minor complications comprised pain and fever (n=6, 32%). Major complications included one hospital death of unknown causes (n=1; 5%). Median follow-up was 7 months (1–16). Four patients (21%) died during the follow-up period. Local tumor control was 76.5% after 6 months and progression-free survival 47% after 6 months. Minimally invasive CT-guided HDR brachytherapy is safe and effective in the palliative treatment of extrahepatic, extrapulmonary secondary malignancies.     

Do vaginal recurrence rates differ among adjuvant vaginal brachytherapy regimens in early-stage endometrial cancer?

PurposeWe sought to retrospectively examine clinical outcomes for three adjuvant vaginal high-dose-rate (HDR) brachytherapy regimens after hysterectomy for early-stage endometrial cancer.MethodsIncluded were women of all ages from two independent hospital systems diagnosed with Stage I-II endometrial cancer of any grade between 2000 and 2016 who underwent hysterectomy followed by adjuvant vaginal cylinder HDR brachytherapy with either 7.0 Gy × 3 fractions prescribed to 0.5 cm vaginal depth, 6.5 Gy × 3 fractions prescribed to 0.5 cm vaginal depth, or 6.0 Gy × 5 fractions prescribed to the vaginal surface. Outcomes included vaginal recurrence (VR), pelvic recurrence, distant recurrence, locoregional recurrence, recurrence-free survival, and overall survival.ResultsOf the 348 women, 45 (13%) received 7.0 Gy × 3 fractions, 259 (74%) received 6.5 Gy × 3 fractions, and 44 (13%) received 6.0 Gy × 5 fractions. Women receiving 5-fraction brachytherapy were more likely to be younger with a higher performance status. At a median follow-up of 4.5 years, VR rates were 2.2%, 0.8%, and 4.5%, respectively. Multivariate analysis revealed no significant differences in the risks for VR among brachytherapy regimens. Risks for VR, pelvic recurrence, distant recurrence, locoregional recurrence, recurrence-free survival, and overall survival did not differ between propensity score–matched five- and 3-fraction brachytherapy cohorts.ConclusionsVR rates after hysterectomy and adjuvant vaginal brachytherapy for early-stage endometrial cancer were low and not significantly different by HDR dose fractionation.     

Transperineal Low-Dose Rate Iridium-192 Interstitial Brachytherapy in Cervical Carcinoma Stage IIB

PURPOSE: To assess local control, survival and complications in patients with cervical carcinoma Stage IIB treated radically with transperineal Iridium-192 low-dose rate interstitial brachytherapy following external beam radiotherapy. PATIENTS AND METHODS: 65 women (age 25-70 years, mean 47 years) with cervical carcinoma Stage IIB were initially treated with external beam radiotherapy on a telecobalt or 6 MV linear accelerator to a dose of 50 Gy delivered in 5-6 weeks. After 2-3 weeks of completing external radiation, patients received interstitial brachytherapy with Iridium-192 (activity 0.5-1 mCi/cm) using a Syed-Neblett perineal template. The median dose delivered to the implant volume was 24 Gy (range 20-32 Gy) delivered at an average dose rate of 0.70 Gy/h (range 0.40-1.20 Gy/h). A point defined at 1.5 cm lateral to the central uterine tandem at the level of os was taken as a representative for assessing the dose to the cervix. Mean doses delivered by interstitial brachytherapy to point A, cervix, point B and rectum were 38 Gy, 34 Gy, 16 Gy and 16 Gy, respectively. RESULTS: At a median follow-up of 53 months, the actuarial disease free survival and overall survival for 65 patients at both 5 and 10 years was 64% and 44%, respectively. Response to radiotherapy was a strong predictor of local control with 82% of patients continuing to have pelvic control after initial complete response. Overall, nine (14%) patients had persistent disease, ten (15%) developed a central recurrence after initial control and three patients developed distant metastasis on follow-up. No patient had any immediate treatment-related complication. Late toxicity included grade I-II rectal reactions in five patients and grade IV bladder complication (vesico-vaginal fistula) in two patients. 5 years after treatment, one patient developed intestinal obstruction, which was relieved after conservative management. Two patients developed vaginal stenosis. The 5- and 10-year disease free survival was 48% in patients aged less than 45 years as compared to 80% in patients of more than 45 years (p = 0.009). Dose to the cervical point was a prognostic indicator with 5- and 10-year disease free survival of 47% in patients who received < 35 Gy in comparison to 80% in patients who had > 35 Gy (p = 0.03). There was no difference in local control and survival in patients with minimal and moderate parametrial involvement. Bulky disease (> 4 cm) at presentation and a longer gap between external radiation and brachytherapy showed a trend towards inferior local control. CONCLUSIONS: Interstitial brachytherapy after external beam irradiation in patients with cervical carcinoma Stage IIB results in acceptable local control, survival and complication rates. Increased dose to the cervical disease results in improved local control and survival and should therefore be considered while optimizing brachytherapy treatment plans. Comparison of the results with those of standard intracavitary therapy remains to be proven in a randomized trial.     

HDR interstitial perineal implant for locally advanced or recurrent uterine cervix cancer

PURPOSE: To evaluate whether high-dose-rate (HDR) interstitial perineal implants can effectively eradicate residual tumor or recurrent tumor in uterine cervix cancer after complete radiation treatment. MATERIALS AND METHODS: This method of treatment was commenced in January 2002, and four advanced stage and four uterine cervix cancer (UCC) recurrences were admitted for this study. All untreated stage II bulky mass and IIIB patients received 50 Gy external beam radiotherapy (EBR) to the whole pelvis prior to the interstitial perineal implant. No EBR was given to recurrent UCC. Brachytherapy was delivered using Martinez Universal Perineal Interstitial Template (MUPIT) and 192Ir HDR. This implant will only be done if residual disease on the parametria was bimanually palpable or was proven by CT scan or MRI. The dose of interstitial brachytherapy boost to the parametria was 17 to 30 Gy, and treatment days ranged from 42 to 64 days. Uterine recurrences were found on the uterine cervix and/or parametria. The dose delivered by this implant ranged from 6 to 16 Gy and encompassed either uterus or vaginal stump and both parametria. Total treatment days ranged from 1 to 2 days. RESULTS: This short-term study showed that almost all tumors were locally controlled when the study was closed (1 to 15 months). One distant metastasis was found. No significant morbidity has been identified until now. CONCLUSION: HDR 192Ir interstitial perineal implants were proven to be effective in eradicating tumor cells in advanced stage UCC and recurrent disease with no significant morbidity.     

Palliative Interstitial HDR Brachytherapy for Recurrent Rectal Cancer

PURPOSE: To report the methods and clinical results of CT-based interstitial high-dose-rate (HDR) brachytherapy procedures for the palliative treatment of recurrent rectal cancer. PATIENTS AND METHODS: A total of 44 brachytherapy implants were performed in 38 patients. CT-guided catheter implants were performed in 34 patients under local anesthesia and sedation, and four patients were implanted intraoperatively. Of 40 CT-guided implants, 20 were done using metallic needles introduced via the sacrum and 20 were transperineal implants of plastic tubes in the presacral region. Postimplant CT scans were used for three-dimensional (3-D) conformal brachytherapy planning. Patients implanted with metallic needles were given a single fraction of 10-15 Gy using HDR (192)Ir, and those who received transperineal implants of plastic catheters were given fractionated brachytherapy, 5 Gy twice daily to a total dose of 30-40 Gy. The median tumor volume was 225 cm(3) with a range of 41-2,103 cm(3). RESULTS: After a median follow-up of 23.4 months, a total of 13/38 patients were alive. The median postbrachytherapy survival was 15 months with 18 of the 25 deaths due to distant metastases. Tumor response was as follows: 6/38 partial remission, 28/38 stable disease, and 4/38 local progression. A planning target volume (PTV) coverage > 85% was achieved in 42/44 implants. The treatment was well tolerated, and no acute complications were observed. One patient developed a fistula after 8 months. Pain relief was recorded in 34 patients (89.5%), and the median duration of this palliative effect was 5 months with a range of 1-13 months. CONCLUSIONS: Interstitial HDR brachytherapy is a valuable tool for the delivery of high doses and achieves effective palliation in recurrent rectal carcinoma.     

Characterization of combined intracavitary/interstitial brachytherapy including oblique needles in locally advanced cervix cancer

PURPOSETo characterize and report on dosimetric outcomes of image guided adaptive brachytherapy (IGABT) using intracavitary and interstitial (IC/IS) applicators including oblique needles (O-needles) in locally advanced cervical cancer (LACC).METHODS AND MATERIALSTwenty LACC patients treated with radio-chemotherapy and offered IC/IS-IGABT including O-needles were analyzed. An in-house 3D-printed vaginal template was used to steer the needles parallel and obliquely in relation to the tandem, supplemented with free-hand needles if needed. Implant characteristics and loading patterns were analyzed. Using the equivalent dose in 2Gy-fractions (EQD2) concept, cumulative (EBRT+BT) V85, V75, V60Gy, targets/OARs doses and high dose volumes (150%, 200% and 300% (100% = 85 Gy EQD2₁₀)) were evaluated.RESULTSMedian(range) tumor width at diagnosis was 5.5(3.6; 7.5)cm; CTV_HR volume was 45(23; 136)cm³ with maximum distance from tandem to CTV_HR border of 3.4(2.5; 4.8)cm. T-stage distribution was IIB/III/IVA in 6(30%)/9(45%)/5(25%) of patients. At BT, 13(65%) patients had distal parametrial/pelvic wall infiltration. Median(range) number of needles per patient was 11(8–18). Average distribution of intrauterine, vaginal and interstitial dwell times were 31%, 25% and 44%, respectively. Median(range) dwell-time per dwell position was 11(2–127)% of average point-A based standard loading. Median V_85Gy/V_150%/V_200%/V_300% were 85(38; 171)/41(21; 93)/22(12; 41)/7(4; 19) cm³; CTV_HR D_90% was 93(83; 97)Gy EQD2₁₀; bladder/rectum/sigmoid/bowel D_2cm3 were 78(64; 104)/65(52; 76)/59(53; 69)/61(47; 76)Gy EQD2₃.CONCLUSIONSThe use of O-needles in patients with large and/or unfavorable tumors resulted in excellent target coverage and OARs sparing. Intrauterine and vaginal loadings were reduced compared to standard loading and almost half of the loading was shifted into IS needles. This was achieved with gentle loading in the majority of dwell positions.     

局部晚期宫颈癌腔内放疗联合组织间插植的剂量学研究

目的 比较局部晚期宫颈癌单纯腔内放疗与腔内联合组织间插植放疗的剂量学差异。方法 2016年5月—2017年3月局部晚期宫颈癌患者共35例,均行根治性放疗,治疗方法为外照射+腔内联合组织间插植放疗。调强放射治疗处方剂量为46.8~50.4 Gy/26~28次,1.8 Gy/次。腔内联合组织间插植放疗剂量为7 Gy/次,1次/周,共4次。同一患者首先置入三管式后装放疗施源器,采集CT图像制定治疗计划,取出三管式施源器后,置入宫腔管并植入插植针,再次采集图像制定放疗计划。分别评价比较两组计划中靶区及危及器官的受照剂量差别。结果 共制定212次后装放疗计划,其中单纯腔内治疗计划106例,腔内联合组织间插植治疗计划106例。腔内联合组织间插植放疗组计划较单纯腔内放疗组的靶区剂量明显升高,高危临床靶区（CTV）的D₉₀、中危CTV的D₉₀均显著增高（t=-6.01、-2.73,P<0.05）,膀胱、直肠、乙状结肠的D_{2 cm³}显著降低（t=3.07、4.52、2.91,P<0.05）。结论 局部晚期宫颈癌应用腔内联合插植放疗可以明显提高靶区剂量,并降低危及器官膀胱、直肠和乙状结肠的受照剂量。     

Clinical outcomes of high-dose-rate interstitial gynecologic brachytherapy using real-time CT guidance

PurposeTo evaluate clinical outcomes of CT-guided high-dose-rate (HDR) interstitial brachytherapy for primary and recurrent gynecologic cancer.Methods and MaterialsRecords were reviewed for 68 women (34 with primary disease and 34 with recurrence) treated with CT-guided HDR interstitial brachytherapy between May 2005 and September 2011. Interstitial application was performed under general anesthesia using an iterative approach of catheter insertion and adjustment with serial image acquisition by CT in a dedicated brachytherapy suite. The median fractional brachytherapy dose was 3.9 Gy delivered twice daily in seven fractions. The median cumulative dose in equivalent 2-Gy fractions was 74.8 Gy. Actuarial survival estimates were calculated using the Kaplan–Meier method, and toxicity was reported by Common Toxicity Criteria.ResultsPrimary disease sites were endometrial (34), cervical (17), vaginal (11), ovarian (3), and vulvar (3). Median age was 61.5 years, and tumor size at diagnosis was 3.4 cm. Median D₉₀ and V₁₀₀ were 73.6 Gy and 87.5%, respectively; median D_2cc for bladder, rectum, and sigmoid were 67.1, 64.6, and 53.7 Gy, respectively. With a median followup of 17 months, actuarial rates of local control, progression-free survival, and overall survival at 2 years for all patients were 86%, 60%, and 64%, respectively. There were 9 grade 3 late toxicities (six gastrointestinal and three vulvovaginal).ConclusionsHDR interstitial brachytherapy with CT-guided catheter placement results in acceptable local control, toxicity, and survival rates for women with primary or recurrent gynecologic cancer. Durable pelvic control may be achieved in most patients with this specialized brachytherapy technique.     

CT-Based Interstitial HDR Brachytherapy

PURPOSE: Development, application and evaluation of a CT-guided implantation technique and a fully CT-based treatment planning procedure for brachytherapy. METHODS AND MATERIALS: A brachytherapy procedure based on CT-guided implantation technique and CT-based treatment planning has been developed and clinical evaluated. For this purpose a software system (PROMETHEUS) for the 3D reconstruction of brachytherapy catheters and patient anatomy using only CT scans has been developed. An interface for the Nucletron PLATO BPS treatment planning system for optimization and calculation of dose distribution has been devised. The planning target volume(s) are defined as sets of points using contouring tools and are used for optimization of the 3D dose distribution. Dose-volume histogram based analysis of the dose distribution (COIN analysis) enables a clinically realistic evaluation of the brachytherapy application to be made. The CT-guided implantation of catheters and the CT-based treatment planning procedure has been performed for interstitial brachytherapy and for different tumor sites in 197 patients between 1996 and 1997. RESULTS: The accuracy of the CT reconstruction was tested using first a quality assurance phantom and second, a simulated interstitial implant of 12 needles. These were compared with the results of reconstruction using radiographs. Both methods gave comparable results with regard to accuracy, but the CT based reconstruction was faster. Clinical feasibility was proved in pre-irradiated recurrences of brain tumors, in pretreated recurrences or metastatic disease, and in breast carcinomas. The tumor volumes treated were in the range 5.1 to 2,741 cm3. Analysis of implant quality showed a slightly significant lower COIN value for the bone implants, but no differences with respect to the planning target volume. CONCLUSIONS: The Offenbach system, incorporating the PROMETHEUS software for interstitial HDR brachytherapy has proved to be extremely valuable in routine clinical practice for many tumor sites. Our CT-guided implantation technique together with a fully CT-based planning system has enabled conformal brachytherapy treatment to become routine.     

Locally recurrent breast cancer: pulse dose rate brachytherapy for repeat irradiation following lumpectomy-- a second chance to preserve the breast

PURPOSE: To perform and assess the effectiveness of local excision of recurrent tumor followed by postoperative pulse dose rate (PDR) brachytherapy. MATERIALS AND METHODS: From 1994 to 2000, 17 patients who had small recurrent breast carcinomas after initially undergoing breast-conserving therapy (BCT), which included postoperative radiation therapy, were treated with local tumor excision and PDR brachytherapy. Recurrences occurred at a median time of 50 months (range, 11-208 months) after primary treatment. Eight patients underwent a combination of PDR brachytherapy (total dose range, 12.5-28.0 Gy) and external-beam radiation therapy (EBT) (total dose range, 12-30 Gy). Nine patients underwent radiation therapy with 40.2-50.0-Gy PDR brachytherapy only. The prescribed radiation dose was 0.5-1.0 Gy per pulse. Patients were examined for local tumor control and treatment-related side effects. RESULTS: Twelve of 17 patients had no local tumor at a median follow-up time of 59 months (range, 20-84 months); two of these patients showed signs of having distant disease. One patient died after a cerebral stroke without evidence of tumor. Four women treated with combined EBT and brachytherapy had secondary local tumor recurrences 4, 8, 8, and 11 months after therapy and had to undergo mastectomy. Despite having undergone radiation therapy previously, patients had side effects limited to moderate (grade 1-2) fibrosis. CONCLUSION: Local tumor excision combined with PDR brachytherapy for small local-regional tumor recurrences after primary BCT is feasible and well tolerated and might obviate mastectomy. Preliminary experiences are encouraging. Further studies are required for appropriate patient selection.     

High-dose-rate endorectal brachytherapy in the treatment of locally advanced rectal carcinoma: technical aspects

PURPOSE: In this era of new radiation technologies and tumor imaging, a high-dose-rate endorectal brachytherapy has been developed and tested in a phase I/II study of advanced rectal tumors. In this article, we report technical aspects of the treatment modality. METHODS AND MATERIALS: Forty-nine patients underwent staging with endoscopic endorectal ultrasound, and the tumor dimensions were determined with MRI of the pelvis. Patients with resectable rectal cancer (staged T2, T3, or early T4) were treated with preoperative high-dose-rate endorectal brachytherapy followed by surgery 6-8 weeks later. Under direct rectoscopy, radio-opaque clips were used to mark the tumor margins. The treatment planning was done with the use of a CT simulator, and the treatment was delivered using a flexible endorectal applicator with eight catheters arranged around the circumference of the applicator and a high-dose-rate brachytherapy remote afterloading system with an Iridium-192 source. Isodose distributions were generated by the Plato planning system (Nucletron B.V., Veenendaal, The Netherlands) and digitally reconstructed radiographs were used as references for daily treatment. A tumor dose of 26 Gy in four fractions was prescribed, and intramesorectal deposits were documented on the magnetic resonance images. RESULTS: Forty-nine patients received planned treatment, and all but 2 patients underwent planned surgery. The pathology specimens showed a complete macroscopic response in 64% of the patients and tumor downstaging in 67% of the patients. CONCLUSIONS: Advances in tumor imaging and 3D treatment planning systems allow for better tumor mapping and dose planning. The use of a multichannel flexible endorectal applicator leads to tumor downstaging before surgery in patients with resectable locally advanced rectal carcinomas. The technique used in our center was practical and validated by this study.     

CT-gesteuerte Brachytherapie

PURPOSE: To assess safety and efficacy of CT-guided brachytherapy of liver malignancies. PATIENTS AND METHODS: 21 patients with 21 liver malignancies (19 metastases, two primary liver tumors) were treated with interstitial CT-guided brachytherapy applying a (192)Ir source. In all patients, the use of image-guided thermal tumor ablation such as by radiofrequency or laser-induced thermotherapy (LITT) was impeded either by tumor size > or = 5 cm in seven, adjacent portal or hepatic vein in ten, or adjacent bile duct bifurcation in four patients. Dosimetry was performed using three-dimensional CT data sets acquired after CT-guided positioning of the brachytherapy catheters. RESULTS: The mean tumor diameter was 4.6 cm (2.5-11 cm). The mean minimal tumor dose inside the tumor margin amounted to 17 Gy (12-20 Gy). The proportion of the liver parenchyma exposed to > 5 Gy was 18% (5-39%) of total liver parenchyma minus tumor volume. Nausea and vomiting were observed in six patients after brachytherapy (28%). One patient demonstrated obstructive jaundice due to tumor edema after irradiation of a metastasis adjacent to the bile duct bifurcation. We commonly encountered asymptomatic increases of liver enzymes. Local control rates after 6 and 12 months were 87% and 70%, respectively. CONCLUSION: CT-guided brachytherapy is safe and effective. This technique displays broader indications compared to image-guided thermal ablation by radiofrequency or LITT with respect to tumor size or localization.     

American Brachytherapy Society consensus guidelines for interstitial brachytherapy for vaginal cancer

PurposeTo present recommendations for the use of interstitial brachytherapy in patients with vaginal cancer or recurrent endometrial cancer in the vagina.MethodsA panel of members of the American Brachytherapy Society reviewed the literature, supplemented that with their clinical experience, and formulated recommendations for interstitial brachytherapy for primary or recurrent cancers in the vagina.ResultsPatients with bulky disease (approximately >0.5 cm thick) should be considered for treatment with interstitial brachytherapy. The American Brachytherapy Society reports specific recommendations for techniques, target volume definition, and dose–fractionation schemes. Three-dimensional treatment planning is recommended with CT scan and/or MRI. The treatment plan should be optimized to conform to the clinical target volume and should reduce the dose to critical organs, including the rectum, bladder, urethra, and sigmoid colon. Suggested doses in combination with external beam radiation therapy and summated equivalent doses in 2 Gy fractions are tabulated.ConclusionRecommendations are made for interstitial brachytherapy for vaginal cancer and recurrent disease in the vagina. Practitioners and cooperative groups are encouraged to use these recommendations to formulate treatment and dose-reporting policies. Such a process will result in meaningful outcome comparisons, promote technical advances, and lead to appropriate utilization of these techniques.     

Reirradiation for Recurrent Neck Metastases of Head-and-Neck Tumors Using CT-Guided Interstitial 192Ir HDR Brachytherapy

PURPOSE: To report the therapeutic results obtained with CT-guided interstitial high-dose-rate brachytherapy (HDR-BRT) as exclusive treatment for recurrent neck metastases of head-and-neck tumors. PATIENTS AND METHODS: Between 1995 and 1999, 49 patients with prior radiation therapy (RT) with or without surgery for primary head-and-neck tumors were treated for recurrent neck metastases located within previously irradiated volumes. All patients had fixed lymphadenopathy with a mean tumor volume of 96 cm(3) (range, 15-452 cm(3)). There were 38 males and eleven females with a mean age of 60 years (range, 28-79 years). All patients had previously received RT as primary or adjuvant treatment with a mean dose of 54 Gy (range, 45-80 Gy). 36 patients (73%) underwent surgery, and 26 (53%) received adjuvant or palliative chemotherapy. The accelerated hyperfractionated interstitial HDR-BRT (2 x 3.0 Gy/day) delivered 30 Gy in 37/49 (75%) and 36 Gy in 12/49 implants (25%). RESULTS: At a minimum 6-week follow-up, the response rate was 83% (41/49) with complete remission in 20% (10/49) and partial remission in 63% (31/49) of the implanted tumor sites. 8/49 patients (17%) did not respond to the treatment. After 19 months of median follow-up, the local control rate was 69% and a total of 15/49 patients (30%) experienced local disease progression. Of these, nine (18%) had locoregional progression and six (12%) progression within the treated volume. The median post-BRT survival was 14 months. The overall survival rate was 52% at 1 year, 31% at 2 years, and 6% at 3 years. CONCLUSION: In patients with recurrent cervical lymphadenopathy of head-and-neck tumors, exclusive interstitial HDR-BRT can provide palliation and tumor control.     

Template-based high-dose-rate interstitial brachytherapy in gynecologic cancers: A single institutional experience

PurposeTo report the outcome and toxicities of radical external beam radiotherapy (EBRT) and template-based high-dose-rate interstitial brachytherapy (ISBT) in patients diagnosed with cervical cancer undergoing inadvertent surgery, vault cancers, and vaginal cancers at our institution.Methods and MaterialsBetween January 2000 and December 2008, 113 patients (37 patients of cervical cancer post-inadvertent surgery, 57 patients with vault cancers, and 19 patients with primary vaginal cancers) were treated with Martinez Universal Perineal Interstitial Template brachytherapy boost after EBRT. The median EBRT dose was 50 Gy, median ISBT dose was 20 Gy, whereas median total dose was 73 Gy equivalent dose at 2 Gy per fraction in all three groups.ResultsMedian followup of surviving patients for the whole group was 43 months (interquartile range, 19–67 months). The 3-year actuarial disease-free survival and overall survival for three groups was 61%, 61%, 59% and 64%, 64%, and 56%, respectively. Grade III/IV rectal toxicity was seen in 11 (10%) patients, bladder toxicity in 5 (4.5%) patients, whereas 7 (6%) patients developed Grade III small bowel toxicity. Residual disease at brachytherapy had significant impact on DFS and OS. Other factors such as age, disease volume, parametrial extension, and vaginal extension did not impact the survivals.ConclusionsMartinez Universal Perineal Interstitial Template–based high-dose-rate ISBT boost in gynecologic cancer results in a reasonable outcome in terms of survivals with acceptable late toxicities. The use of template-based ISBT is associated with a definite learning curve.