The effect of alternative biological modelling parameters (α/β and half time of repair T1/2) on reported EQD2 values in the treatment of advanced cervical cancer

Purpose

To evaluate the effect of different α/β and half-time of repair T_½ on the assessment of clinical treatment plans for patients with cervical cancer.

Materials and methods

We used EBRT and BT treatment plans of five patients, planned with MRI guided BT. We computed 3D EQD2 dose distributions of combined EBRT and BT treatments and calculated D90 of high-risk clinical target volume (HR-CTV) and D_2cc for bladder and rectum, and the ratio D_2cc(bladder)/D90(HR-CTV). BT was modelled as PDR (two applications of 32 × 60 cGy) and HDR (two applications of 2 × 7 Gy). We assumed a low, standard and high value for the biological parameters: HR-CTV α/β = 5/10/15 Gy and T_½ = 0.5/1.5/2.5 h; OAR α/β = 2/3/4 Gy; T_½ = 0.5/1.5/4.5 h.

Results

The chosen variation in modelling parameters had a much larger effect on PDR treatments than on HDR treatments, especially for OAR, thus creating larger uncertainties. The relative mean range of the ratio D_2cc(bladder)/D90(HR-CTV) is 72% for PDR and 25% for HDR. Out of the 125 modelled combinations 48 PDR plans and 23 HDR plans comply with clinical objectives.

Conclusion

For HDR brachytherapy, only α/β has a significant impact on reported EQD2 values, whereas for PDR both α/β and T_1/2 are important.Generally, the ratio D_2cc(bladder)/D90(HR-CTV) is more favourable for PDR, even considering the larger uncertainties in EQD2.     

Applicator reconstruction and applicator shifts in 3D MR-based PDR brachytherapy of cervical cancer

Purpose

To evaluate the methods of applicator reconstruction in 3D MR-based planning for brachytherapy of cervical cancer, and to investigate applicator shifts and changes in DVH parameters during PDR treatment.

Methods

For each application MR scans with applicator in situ were made: three T2-weighted (4.5 mm slices) Turbo Spin Echo (TSE) scans and a balanced Steady State Free Precession scan (1.5 mm). Three observers tested two applicator reconstruction methods: (A) directly on the bSSFP scan and (B) on a resampled combination of the three T2-weighted scans. For 10 patients MR imaging was repeated on the second day of each PDR fraction to determine applicator shifts and changes in DVH parameters.

Results

For both applicator reconstruction methods the interobserver variation for the DVH parameters was comparable (average <1.5% in dose). Differences between the two methods were larger (up to 6.4% for target) and were related to position differences during MR scanning.The average applicator shift relative to the pelvic structures was 5-6 mm into the ventral direction and 3-4 mm cranially. For a single PDR fraction, the average D90 (HR-CTV) on ‘day 2’ was 0.2 (SD 2.0) Gy lower than that for day 1. The average increase in D_2cc (bladder) was 1.0 (SD 3.0) Gy_αβ3 for a single PDR fraction. If the effect of both fractions was combined, for 1 patient a total decrease of D90 of 7 Gy_αβ10 was found, whereas for another patient the total increase in bladder dose was 12 Gy_αβ3.

Conclusions

Applicator reconstruction on MR data is feasible. In the overall accuracy during PDR brachytherapy the reconstruction uncertainty is of minor importance. Applicator and/or organ movement during the course of the PDR fraction produce larger uncertainties.     

Is single fraction 15 Gy the preferred high dose-rate brachytherapy boost dose for prostate cancer?

Background and purpose

High dose-rate (HDR) brachytherapy is most commonly administered as a boost in two or more fractions combined with external beam radiotherapy (EBRT). Our purpose is to compare outcomes with a single fraction HDR boost to that with a standard fractionated boost in intermediate risk prostate cancer.

Materials and methods

Results of two sequential phase II clinical trials are compared. The Single Fraction protocol consists of 15 Gy HDR in one fraction followed by 37.5 Gy EBRT in 15 fractions over 3 weeks; the Standard Fractionation protocol consisted of two HDR fractions each of 10 Gy, 1 week apart, followed by 45 Gy EBRT in 25 fractions. Patients had intermediate risk disease, and were well balanced for prognostic factors. Patients were followed prospectively for efficacy, toxicity and health-related quality of life (Expanded Prostate Index Composite). Efficacy was assessed biochemically using the Phoenix definition, and by biopsy at 2 years.

Results

The Single Fraction protocol accrued 123 patients and the Standard Fractionation protocol, 60. With a median follow-up of 45 and 72 months, respectively, the biochemical disease-free survival was 95.1% and 97.9% in the Single and Standard Fractionation trials (p = 0.3528). Two-year prostate biopsy was positive in only 4% and 8%, respectively. There was no difference in late urinary or rectal toxicity rates, or in health-related quality of life between the two protocols.

Conclusions

The Single Fraction HDR protocol results in high disease control rate and low toxicity similar to our previous protocol using two HDR insertions, with significant savings in resources. While mature results with longer follow-up are awaited, a single 15 Gy may be considered as a standard fractionation regimen in combination with EBRT for men with intermediate risk disease.     

MRI-guided treatment-planning optimisation in intracavitary or combined intracavitary/interstitial PDR brachytherapy using tandem ovoid applicators in locally advanced cervical cancer

Purpose

To study the impact of MRI-guided treatment planning on dose/volume parameters in pulsed dose rate (PDR) brachytherapy (BT) for cervical cancer. Additionally, we investigated the potential benefit of an intracavitary/interstitial (IC/IS) modification of the classical tandem ovoid applicator.

Material and methods

For 24 patients we compared Standard PDR BT plans, Scaled Standard plans and MRI-guided Optimised plans. The total EBRT/BT prescribed dose to Manchester point A or to 90% of the HR-CTV (D90 HR-CTV) [1] expressed in EQD₂ was 80 Gy_αβ10 in 17 patients (Period I) and 84 Gy_αβ10 in 7 patients (Period II). The constraints to 2 cm³ of the OAR were 90 Gy_αβ3 for bladder and 75 Gy_αβ3 for rectum, sigmoid and bowel. Most cases were treated with a traditional intracavitary tandem ovoid applicator. In 6 patients we used a newly designed combined IC/IS modification for the second PDR fraction and investigated the benefit of the interstitial part.

Results

The average gain of MRI-guided optimisation expressed in D90 HR-CTV was 4 ± 9 Gy_αβ10 (p < 0.001) and 10 ± 7 Gy_αβ10 (p = 0.003) in the two periods. The dose to 2 cm³ of the OAR met the constraints. In the group that was treated with the combined IC/IS approach, we could increase the D90 HR-CTV for the second PDR fraction with 5.4 ± 4.2 Gy_αβ10 (p = 0.005) and the D100 with 4.8 ± 3.1 Gy_αβ10 (p = 0.07).

Conclusions

Three-dimensional MRI-guided treatment planning and optimisation improves the DVH parameters compared to conventional planning strategies. Additional improvement can be achieved by using a combined IC/IS approach.     

Prostate-specific antigen kinetics following external-beam radiotherapy and temporary (Ir-192) or permanent (I-125) brachytherapy for prostate cancer

Background and purpose

The aim of the study was the evaluation of PSA kinetics after different radiotherapy methods.

Materials and methods

Two-hundred and ninety five patients received external-beam radiotherapy (EBRT; 70.2 Gy; n = 135), Ir-192 brachytherapy as a boost to EBRT (HDR-BT; 18 Gy + 50.4 Gy; n = 66) or I-125 brachytherapy (LDR-BT; 145 Gy; n = 94) as monotherapy. “PSA bounce” was defined as a PSA rise of ?0.2 ng/ml followed by spontaneous return to prebounce level or lower, biochemical failure as “nadir + 2 ng/ml”.

Results

Patients without biochemical failure reached a lower nadir after brachytherapy (median ?0.05 ng/ml after LDR- and HDR-BT without NHT) in comparison to EBRT (0.55 ng/ml without NHT; p < 0.01). Not a single patient without NHT and a nadir <0.1 ng/ml failed biochemically (0% vs. 45% with a nadir ?0.1 ng/ml; p < 0.01). PSA bounces were found predominantly in the LDR-BT group (42% vs. 23%/20% after HDR-BT/EBRT; p < 0.01). In a multivariate Cox regression analysis, LDR-BT and HDR-BT were associated with a significantly lower biochemical failure rate in comparison to EBRT.

Conclusions

PSA kinetics differ significantly following different radiotherapy methods. A lower nadir and a higher biochemical control rate suggest a higher radiobiological efficiency of brachytherapy in comparison to EBRT (with a dose of 70.2 Gy).     

Justification for inter-fraction correction of catheter movement in fractionated high dose-rate brachytherapy treatment of prostate cancer

Background and purpose

Fractionated high dose-rate (HDR) brachytherapy in the treatment of prostate cancer relies on reproducible catheter positions for each fraction to ensure adequate tumour coverage while minimising dose to normal tissues. Peri-prostatic oedema may cause caudal displacement of the catheters relative to the prostate gland between fractions. This can be corrected for by changing source dwell positions or by physical re-advancement of catheters before treatment.

Materials and methods

Data for 20 consecutive monotherapy patients receiving three HDR fractions of 10.5 Gy per fraction over 2 days were analysed retrospectively. Pre-treatment CT scans were used to assess the effect of catheter movement between fractions on implant quality, with and without movement correction. Implant quality was evaluated using dosimetric parameters.

Results

Compared to the first fraction (f1) the mean inter-fraction caudal movement relative to the prostate base was 7.9 mm (f2) (range 0-21 mm) and 3.9 mm (f3) (range 0-25.5 mm). PTV D90% was reduced without movement correction by a mean of 27.8% (f2) and 32.3% (f3), compared with 5.3% and 5.1%, respectively, with catheter movement correction. Dose to 2 cc of the rectum increased by a mean of 0.69 (f2) and 0.76 Gy (f3) compared with an increase of 0.03 and 0.04 Gy, respectively, with correction. The urethra V12 also increased by a mean of 0.36 (f2) and 0.39 Gy (f3) compared with 0.06 and 0.16 Gy, respectively, with correction.

Conclusions

Inter-fraction correction for catheter movement using pre-treatment imaging is critical to maintain the quality of an implant. Without movement correction there is significant risk of tumour under-dosage and normal tissue over-dosage. The findings of this study justify additional imaging between fractions in order to carry out correction.     

‘Plan of the day’ adaptive radiotherapy for bladder cancer using helical tomotherapy

Background and purpose

This study assessed the potential of tomotherapy based Image Guided Radiotherapy (IGRT) to increase the accuracy of bladder irradiation using a ‘plan of the day’ adaptive radiotherapy (ART) technique.

Materials and methods

Ten patients with muscle invasive bladder cancer underwent bladder preservation with trimodality therapy in an ongoing trial. All patients received 64 Gy/32# to the whole bladder and seven of them received a boost of 68 Gy/32# to the tumour bed. The ART technique entailed the generation of six IMRT plans for each patient, using six isotropic PTVs of 5-30 mm applied to the bladder volume (CTV) to generate the PTVs. Megavoltage CT (MVCT) imaging was done to correct positioning errors and choose the ‘plan of the day’.

Results

Post treatment MVCT scans (315 scans) were used to generate multiple anisotropic PTVs for three hypothetical scenarios. Overall, coverage of anterior and superior walls required larger margins than other walls. Maximum geographical miss, in spite of IGRT, was noted for the superior (13.8%) and anterior walls (10.3%).

Conclusions

Plan of the day ART is a feasible and promising technique for optimal treatment and dose escalation in bladder cancer.     

Sigmoid dose using 3D imaging in cervical-cancer brachytherapy

Background and Purpose

To evaluate the proximity, variance, predictors of dose, and complications to the sigmoid in cervical-cancer brachytherapy using 3D planning.

Materials and methods

Over 36 months, 50 patients were treated for cervical cancer with either low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy. The distance from the central tandem to the sigmoid, the D0.1cc and the D2cc to the sigmoid, rectum and bladder doses, and toxicity were analyzed.

Results

The median sigmoid EQD2 D0.1cc and D2cc were 84 Gy and 68.3 Gy for HDR versus 71.1 Gy and 65.9 Gy for LDR (p = 0.02 and 0.98, respectively). Twenty percent of the HDR fractions required manipulation of the superior dwell positions to decrease the sigmoid dose. The median distance from the sigmoid to the tandem was 1.7 cm (range [rg], 0.1-6.16 cm) for HDR and 2.7 cm (rg, 1.17-4.52 cm) for LDR; from the sigmoid to the 100% isodose region the median distances were −0.1 cm (rg, −1.4 to 2.5 cm) and 0.44 cm (rg. −0.73-5.2 cm), respectively. The proximity of the sigmoid to the tandem is significantly related to sigmoid dose (p < 0.0001). Within-patient (among-fraction) variation in sigmoid-to-tandem distance during HDR was substantial (coefficient of variation =40%). No grade 3-4 sigmoid toxicity was seen after a median 31-month follow-up period.

Conclusions

3D imaging in cervical-cancer brachytherapy shows the sigmoid in close proximity to the tandem. The sigmoid-to-tandem distance varies substantially between fractions, indicating the importance of sigmoid dose-volume evaluation with each fraction.     

Comparison of three radiotherapy modalities on biochemical control and overall survival for the treatment of prostate cancer: A systematic review

Background and Purpose

For the radiation treatment of prostate cancer high dose should be delivered for optimal biochemical control. Treatment can be given by dose-escalated external beam radiotherapy (EBRT) or external beam radiotherapy combined with a radioactive seed implantation (EBSeeds) or high-dose rate (HDR) brachytherapy (EBTI). Differences in outcome between the modalities were assessed by a systematic review.

Materials and methods

A systematic search was performed resulting in 40 articles to be used. Data were extracted on biochemical control and overall survival at 3, 5, and 8 years and other time points mentioned in the articles. Also known prognostic parameters were noted. Comparison of the modalities was done by a Weibull survival analysis and estimation of Hazard Ratio’s (HR) was done with 95% confidence intervals (95% CIs).

Results

The HR for biochemical recurrence was 1.40 (95% CI 1.31-1.51) for EBRT relative to EBTI, and was 1.37 (95% CI 1.26-1.49) for EBSeeds relative to EBTI. The HR for overall survival was 1.50 (95% CI 1.29-1.73) for EBRT relative to EBTI, and was 2.33 (95% CI 2.04-2.66) for EBSeeds relative to EBTI.

Conclusion

The combination of external beam radiotherapy and HDR brachytherapy results in a superior biochemical control and overall survival found in a systematic review on radiotherapy for prostate cancer.     

External beam radiotherapy plus single-fraction high dose rate brachytherapy in the treatment of locally advanced prostate cancer

Purpose

To evaluate the efficacy and toxicity of external beam radiation therapy (EBRT) plus high-dose-rate brachytherapy (HDRB) as a boost in patients (pts) with intermediate or high-risk prostate cancer.

Methods and materials

From 2002 to July 2012, 377 pts with a diagnosis of intermediate or high-risk prostate cancer were treated with EBRT plus HDRB. Median patient age was 66 years (range, 41–86). Most patients (347 pts; 92%) were classified as high-risk (stage T2c–T3, or PSA > 20 ng/mL, or GS ? 8), with 30 patients (8%) considered intermediate risk. All patients underwent EBRT at a prescribed dose of 60.0 Gy (range, 45–70 Gy) to the prostate and seminal vesicles. A total of 120 pts (31%) received a dose of 46 Gy (45–50 Gy) to the true pelvis. All pts received a single-fraction 9 Gy (9–15 Gy) HDR boost. Most patients (353; 94%) were prescribed complete androgen deprivation therapy (ADT). Overall survival (OS), cause-specific survival (CSS), and biochemical relapse-free survival (BRFS) rates were calculated. In the case of BRFS, patients with <26 months of follow-up (n = 106) were excluded to minimize the impact of ADT.

Results

The median follow-up for the entire sample was 50 months (range, 12–126), with 5-year actuarial OS and CSS, respectively, of 88% (95% confidence interval [CI]: 84–92) and 98% (95% CI: 97–99). The 5-year BRFS was 91% (95% CI: 87–95) in the 271 pts with ?26 months (median, 60 months) of follow-up. Late toxicity included grade 2 and 3 gastrointestinal toxicity in 17 (4.6%) and 6 pts (1.6%), respectively, as well as grades 2 and 3 genitourinary toxicity in 46 (12.2%) and 3 pts (0.8%), respectively.

Conclusion

These long-term outcomes confirm that EBRT plus a single-fraction HDRB boost provides good results in treatment-related toxicity and biochemical control. In addition to the excellent clinical results, this fractionation schedule reduces physician workload, treatment-related expenses, patient discomfort and risks associated with anaesthesia. We believe these findings support the use of single-fractionation boost techniques.     

Monotherapeutic high-dose-rate brachytherapy for prostate cancer: A dose reduction trial

Purpose

To report preliminary results of our second regimen with 45.5 Gy/7 fractions aiming to reduce toxicity, compared with our first regimen with 54 Gy/9 fractions, using high-dose-rate (HDR) brachytherapy as monotherapy for prostate cancer.

Materials and methods

From 2005 through 2010, 63 patients with localized prostate cancer were treated with HDR brachytherapy alone in 45.5 Gy/7 fractions for 4 days. Thirty-four patients were considered as intermediate-risk and 29 as high-risk. Thirty-seven patients also received neoadjuvant and/or adjuvant hormonal therapy. Biologically effective dose assuming α/β = 1.5 Gy (BED_1.5) was reduced from 270 Gy to 243 Gy, and BED_3.0 from 162 Gy to 144 Gy, compared to previous 54 Gy/9 fractions for 5 days.

Results

Median follow-up time was 42 months (range 13–72). Grade 2 acute toxicities occurred in six (9.5%), late toxicities in five (7.9%) patients, and Grade 3 or higher in none. Grade 2 late gastrointestinal toxicity rate was 1.6%, compared with 7.1% for the 54 Gy regimen. Three-year PSA failure-free rates for intermediate- and high-risk patients were 96% and 90%, which were comparable to 93% and 85% for the 54 Gy regimen.

Conclusions

Compared to the 54 Gy/9 fractions regimen, dose-reduced regimen of 45.5 Gy/7 fractions using HDR brachytherapy as monotherapy preliminarily showed an equivalent or lower incidence rate for acute and late toxicities without compromising the excellent PSA failure-free rate. Further studies with more patients and longer follow-up are warranted.     

Prostate HDR brachytherapy catheter displacement between planning and treatment delivery

Background and purpose

HDR brachytherapy is used as a conformal boost for treating prostate cancer. Given the large doses delivered, it is critical that the volume treated matches that planned. Our outpatient protocol comprises two 9 Gy fractions, two weeks apart. We prospectively assessed catheter displacement between CT planning and treatment delivery.

Materials and methods

Three fiducial markers and the catheters were implanted under transrectal ultrasound guidance. Metal marker wires were inserted into 4 reference catheters before CT; marker positions relative to each other and to the marker wires were measured from the CT scout. Measurements were repeated immediately prior to treatment delivery using pelvic X-ray with marker wires in the same reference catheters. Measurements from CT scout and film were compared. For displacements of 5 mm or more, indexer positions were adjusted prior to treatment delivery.

Results

Results are based on 48 implants, in 25 patients. Median time from planning CT to treatment delivery was 254 min (range 81-367 min). Median catheter displacement was 7.5 mm (range −2.9-23.9 mm), 67% of implants had displacement of 5 mm or greater. Displacements were predominantly caudal.

Conclusions

Catheter displacement can occur in the 1-3 h between the planning CT scan and treatment. It is recommended that departments performing HDR prostate brachytherapy verify catheter positions immediately prior to treatment delivery.     

Urethral stricture following high dose rate brachytherapy for prostate cancer

Purpose

To evaluate the incidence, timing, nature and outcome of urethral strictures following high dose rate brachytherapy (HDRB) for prostate carcinoma.

Methods and materials

Data from 474 patients with clinically localised prostate cancer treated with HDRB were analysed. Ninety percent received HDRB as a boost to external beam radiotherapy (HDRBB) and the remainder as monotherapy (HDRBM). Urethral strictures were graded according to the Common Terminology Criteria for Adverse Events v3.0.

Results

At a median follow-up of 41 months, 38 patients (8%) were diagnosed with a urethral stricture (6-year actuarial risk 12%). Stricture location was bulbo-membranous (BM) urethra in 92.1%. The overall actuarial rate of grade 2 or more BM urethral stricture was estimated at 10.8% (95% CI 7.0-14.9%), with a median time to diagnosis of 22 months (range 10-68 months). All strictures were initially managed with either dilatation (n = 15) or optical urethrotomy (n = 20). Second line therapy was required in 17 cases (49%), third line in three cases (9%) and 1 patient open urethroplasty (grade 3 toxicity). Predictive factors on multivariate analysis were prior trans-urethral resection of prostate (hazard ratio (HR) 2.81, 95% CI 1.15-6.85, p = 0.023); hypertension (HR 2.83, 95% CI 1.37-5.85, p = 0.005); and dose per fraction used in HDR (HR for 1 Gy increase per fraction 1.33, 95% CI 1.08-1.64, p = 0.008).

Conclusions

BM urethral strictures are the most common late grade 2 or more urinary toxicity following HDR brachytherapy for prostate cancer. Most are manageable with minimally invasive procedures. Both clinical and dosimetric factors appear to influence the risk of stricture formation.     

Analysis of dose-volume histogram parameters for radiation pneumonitis after definitive concurrent chemoradiotherapy for esophageal cancer

Purpose

To evaluate dose-volume histogram (DVH) parameters as predictors of radiation pneumonitis (RP) in esophageal cancer patients treated with definitive concurrent chemoradiotherapy.

Patients and methods

Thirty-seven esophageal cancer patients treated with radiotherapy with concomitant chemotherapy consisting of 5-fluorouracil and cisplatin were reviewed. Radiotherapy was delivered at 2 Gy per fraction to a total of 60 Gy. For most of the patients, two weeks of interruption was scheduled after 30 Gy. The percentage of lung volume receiving more than 5-50 Gy in increments of 5 Gy (V5-V50, respectively), and the mean lung dose (MLD) were analyzed.

Results

Ten (27%) patients developed RP of grade 2; 2 (5%), grade 3; 0 (0%), grade 4; and 1 (3%), grade 5. By univariate analysis, all DVH parameters (i.e., V5-V50 and MLD) were significantly associated with grade ?2 RP (p < 0.01). The incidences of grade ?2 RP were 13%, 33%, and 78% in patients with V20s of ?24%, 25-36%, and ?37%, respectively. The optimal V20 threshold to predict symptomatic RP was 30.5% according to the receiver operating characteristics curve analysis.

Conclusion

DVH parameters were predictors of symptomatic RP and should be considered in the evaluation of treatment planning for esophageal cancer.     

Image and laparoscopic guided interstitial brachytherapy for locally advanced primary or recurrent gynaecological cancer using the adaptive GEC ESTRO target concept

Purpose

To retrospectively assess treatment outcome of image and laparoscopic guided interstitial pulsed dose rate brachytherapy (PDR-BT) for locally advanced gynaecological cancer using the adaptive GEC ESTRO target concept.

Materials and methods

Between June 2005 and December 2010, 28 consecutive patients were treated for locally advanced primary vaginal (nine), recurrent endometrial (12) or recurrent cervical cancer (seven) with combined external beam radiotherapy (EBRT) and interstitial PDR-BT. Treatment was initiated with whole pelvic EBRT to a median dose of 45 Gy followed by PDR-BT using the Martinez Universal Perineal Interstitial Template (MUPIT). All implants were virtually preplanned using MRI of the pelvis with a dummy MUPIT in situ. The GEC ESTRO high risk clinical target volume (HR CTV), intermediate risk clinical target volume (IR CTV) and the organs at risk (OAR) were contoured and a preplan for implantation was generated (BrachyVision, Varian). The subsequent implantation was performed under laparoscopic visualisation. Final contouring and treatment planning were done using a post-implant CT. Planning aim of PDR-BT was to deliver 30 Gy in 50 hourly pulses to HR CTV. Manual dose optimisation was performed with the aim of reaching a D90 > 80 Gy in the HR CTV calculated as the total biologically equivalent to 2 Gy fractions of EBRT and BT (EQD2). Dose to the OAR were evaluated using dose volume constraints for D_2cc of 90 Gy for bladder and 70 Gy for rectum and sigmoid.

Results

For HR CTV the median volume was 26 cm³ (7-91 cm³). Coverage of the HR CTV was 97% (90-100%) and D90 was 82 Gy (77-88 Gy). The D_2cc for bladder, rectum, and sigmoid were 65 Gy (47-81 Gy), 61 Gy (50-77 Gy), and 52 Gy (44-68 Gy), respectively. Median follow up was 18 months (6-61 months). The actuarial 2 years local control rate was 92% (SE 5), while disease-free survival and overall survival were 59% (SE 11) and 74%, respectively (SE 10). No complications to the laparoscopic guided implantation were encountered. Late grade 2 (CTC v 3.0) complications were recorded in nine (32%) patients. One patient had a grade 3 vaginal complication. No grade 4-5 complications have been recorded so far.

Conclusion

Image and laparoscopic guided interstitial PDR-BT using the GEC ESTRO target concept is applicable for locally advanced primary vaginal or recurrent endometrial and cervical cancer resulting in an excellent local control rate and limited morbidity.     

Hypofractionated accelerated CT-guided interstitial Ir-HDR-Brachytherapy as re-irradiation in inoperable recurrent cervical lymphadenopathy from head and neck cancer

Background

Despite significant improvements in the treatment of head and neck cancer (HNC), lymph node recurrences remain a clinical challenge after primary radiotherapy. The value of interstitial (IRT) brachytherapy (BRT) for control of lymph node recurrence remains unclear. In order to clarify its role a retrospective review was undertaken on the value of computed tomography (CT)-guided IRT high-dose-rate (HDR)-BRT in isolated recurrent disease from HNC.

Patients and methods

From 2000 to 2007, 74 patients were treated for inoperable recurrent cervical lymphadenopathy. All patients had previously been treated with radical radiotherapy or chemoradiation with or without surgery. The HDR-BRT delivered a median salvage dose of 30.0 Gy (range, 12.0-36.0 Gy) in twice-daily fractions of 2.0-5.0 Gy in 71 patients and of 30.0 Gy (range, 10.0-36.0 Gy) in once-daily fractions of 6.0-10.0 Gy in three patients.

Results

The overall and disease-free survival rates at one, two and three years were 42%, 19%, 6%, and 42%, 37% and 19%, respectively. The local control probability at one, two and three years was 67% at all three time points. Grade III-IV complications occurred in 13% of patients.

Conclusions

In patients with inoperable recurrent neck disease from HNC, hypofractionated accelerated CT-guided IRT-HDR-BRT can play an important role in providing palliation and tumor control.     

Late toxicity after postprostatectomy salvage radiation therapy

Purpose

To evaluate late toxicity in patients who received salvage external beam radiotherapy (EBRT) for a detectable prostate-specific antigen (PSA) level after radical prostatectomy (RP).

Methods

A cohort of 308 consecutive patients underwent salvage EBRT from July 1987 through June 2003 for a detectable PSA level after RP. All were treated with high-energy photons (6-20 MV) to a median dose of 64.8 Gy (range: 54.0-72.4 Gy) in 1.8- to 2.0-Gy fractions.

Results

Median follow-up from the completion of EBRT was 60 months (range: 1 day-174 months). Late toxicity occurring more than 90 days after EBRT completion was identified in 41 patients (13%). Twelve patients (3.9%) had grade 2 urethral strictures and were treated with urethral dilation, 3 patients had grade 3 cystitis, and 1 had a grade 4 rectal complication. These numbers correspond to an estimated 0.7% (95% confidence interval, 0.0-1.6%) of patients experiencing a grade 3 or 4 complication by 5 years after the start of EBRT.

Conclusions

Salvage EBRT for a detectable PSA level after RP is the only curative treatment in this setting. This treatment can be administered in a manner that results in a low likelihood of late complications.