Jan Willem M. Mens

Quality of Life After Pelvic Radiotherapy or Vaginal Brachytherapy for Endometrial Cancer: First Results of the Randomized PORTEC-2 Trial

PURPOSE Studies on quality of life (QOL) among women with endometrial cancer have shown that patients who undergo pelvic radiotherapy report lower role functioning and more diarrhea and fatigue. In the Post Operative Radiation Therapy in Endometrial Cancer (PORTEC) trial, patients with endometrial carcinoma were randomly assigned to receive external-beam radiotherapy (EBRT) or vaginal brachytherapy (VBT). QOL was evaluated by using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 and subscales from the prostate cancer module, PR-25, and the ovarian cancer module, OV-28. PATIENTS AND METHODS PORTEC-2 accrued 427 patients between 2002 and 2006, of whom 214 were randomly assigned to EBRT, and 213 were randomly assigned to VBT. Three-hundred forty-eight patients (81%) were evaluable for QOL. QOL outcomes were analyzed at a median follow-up of 2 years. Results At baseline after surgery, patient functioning was at the lowest level, and it increased during and after radiotherapy to reach a plateau after 12 months. Patients in the VBT group reported better social functioning (P < .002) and lower symptom scores for diarrhea, fecal leakage, the need to stay close to the toilet, and limitation in daily activities because of bowel symptoms (P < .001). At baseline, 15% of patients were sexually active; this increased significantly to 39% during the first year (P < .001). Sexual functioning and symptoms did not differ between the treatment groups. CONCLUSION Patients who received EBRT reported significantly higher levels of diarrhea and bowel symptoms. This resulted in a higher need to remain close to a toilet and, as a consequence, more limitation of daily activities because of bowel symptoms and decreased social functioning. Vaginal brachytherapy provides a better QOL, and should be the preferred treatment from a QOL perspective.

Fifteen-year radiotherapy outcomes of the randomized PORTEC-1 trial for Endometrial Carcinoma

PURPOSE To evaluate the very long-term results of the randomized Post Operative Radiation Therapy in Endometrial Carcinoma (PORTEC)-1 trial for patients with Stage I endometrial carcinoma (EC), focusing on the role of prognostic factors for treatment selection and the long-term risk of second cancers. PATIENTS AND METHODS The PORTEC trial (1990-1997) included 714 patients with Stage IC Grade 1-2 or Stage IB Grade 2-3 EC. After surgery, patients were randomly allocated to external-beam pelvic radiotherapy (EBRT) or no additional treatment (NAT). Analysis was by intention to treat. RESULTS 426 patients were alive at the date of analysis. The median follow-up time was 13.3 years. The 15-year actuarial locoregional recurrence (LRR) rates were 6% for EBRT vs. 15.5% for NAT (p < 0.0001). The 15-year overall survival was 52% vs. 60% (p = 0.14), and the failure-free survival was 50% vs. 54% (p = 0.94). For patients with high-intermediate risk criteria, the 15-year overall survival was 41% vs. 48% (p = 0.51), and the 15-year EC-related death was 14% vs. 13%. Most LRR in the NAT group were vaginal recurrences (11.0% of 15.5%). The 15-year rates of distant metastases were 9% vs. 7% (p = 0.25). Second primary cancers had been diagnosed over 15 years in 19% of all patients, 22% vs. 16% for EBRT vs. NAT (p = 0.10), with observed vs. expected ratios of 1.6 (EBRT) and 1.2 (NAT) compared with a matched population (p = NS). Multivariate analysis confirmed the prognostic significance of Grade 3 for LRR (hazard ratio [HR] 3.4, p = 0.0003) and for EC death (HR 7.3, p < 0.0001), of age >60 (HR 3.9, p = 0.002 for LRR and 2.7, p = 0.01 for EC death) and myometrial invasion >50% (HR 1.9, p = 0.03 and HR 1.9, p = 0.02). CONCLUSIONS The 15-year outcomes of PORTEC-1 confirm the relevance of HIR criteria for treatment selection, and a trend for long-term risk of second cancers. EBRT should be avoided in patients with low- and intermediate-risk EC.

Hyperthermia dose-effect relationship in 420 patients with cervical cancer treated with combined radiotherapy and hyperthermia

Adding hyperthermia to standard radiotherapy (RT+HT) improves treatment outcome for patients with locally advanced cervical cancer (LACC). We investigated the effect of hyperthermia dose on treatment outcome for patients with LACC treated with RT+HT. We collected treatment and outcome data of 420 patients with LACC treated with hyperthermia at our institute from 1990 to 2005. Univariate and multivariate analyses were performed on response rate, local control, disease-specific survival and toxicity for these patients to search for a thermal dose response relationship. Besides commonly identified prognostic factors in LACC like tumour stage, performance status, radiotherapy dose and tumour size, thermal parameters involving both temperature and duration of heating emerged as significant predictors of the various end-points. The more commonly used CEM43T90 (cumulative equivalent minutes of T90 above 43 degrees C) was less influential than TRISE (based on the average T50 increase and the duration of heating, normalised to the scheduled duration of treatment). CEM43T90 and TRISE measured intraluminally correlate significantly and independently with tumour control and survival. These findings stimulate further technological development and improvement of deep hyperthermia, as they strongly suggest that it might be worthwhile to increase the thermal dose for LACC, either by treatment optimisation or by prolonging the treatment time. These results also confirm the beneficial effects from hyperthermia as demonstrated in our earlier randomised trial, and justify applying radiotherapy and hyperthermia as treatment of choice for patients with advanced cervical cancer.

Five-year quality of life of endometrial cancer patients treated in the randomised Post Operative Radiation Therapy in Endometrial Cancer (PORTEC-2) trial and comparison with norm data.

BACKGROUND The PORTEC-2 trial showed efficacy and reduced side-effects of vaginal brachytherapy (VBT) compared with external beam pelvic radiotherapy (EBRT) for patients with high-intermediate risk endometrial cancer. The current analysis was done to evaluate long-term health related quality of life (HRQL), and compare HRQL of patients to an age-matched norm population. METHODS Patients were randomly allocated to EBRT (n=214) or VBT (n=213). HRQL was assessed using EORTC QLQ-C30 and subscales from PR25 and OV28 (bladder, bowel, sexual symptoms); and compared to norm data. FINDINGS Median follow-up was 65 months; 348 (81%) patients were evaluable for HRQL (EBRT n=166, VBT n=182). At baseline, patient functioning was at lowest level, increasing during and after radiotherapy to reach a plateau after 12 months, within range of scores of the norm population. VBT patients reported better social functioning (p=0.005) and lower symptom scores for diarrhoea, faecal leakage, need to stay close to a toilet and limitation in daily activities due to bowel symptoms (p⩽0.001), compared to EBRT. There were no differences in sexual functioning or symptoms between the treatment groups; however, sexual functioning was lower and sexual symptoms more frequent in both treatment groups compared to the norm population. INTERPRETATION Patients who received EBRT reported clinically relevant higher levels of bowel symptoms and related limitations in daily activities with lower social functioning, 5 years after treatment. VBT provides a better HRQL, which remained similar to that of an age-matched norm population, except for sexual symptoms which were more frequent in both treatment groups.

Individualized nonadaptive and online-adaptive intensity-modulated radiotherapy treatment strategies for cervical cancer patients based on pretreatment acquired variable bladder filling computed tomography scans

PURPOSE To design and evaluate individualized nonadaptive and online-adaptive strategies based on a pretreatment established motion model for the highly deformable target volume in cervical cancer patients. METHODS AND MATERIALS For 14 patients, nine to ten variable bladder filling computed tomography (CT) scans were acquired at pretreatment and after 40 Gy. Individualized model-based internal target volumes (mbITVs) accounting for the cervix and uterus motion due to bladder volume changes were generated by using a motion-model constructed from two pretreatment CT scans (full and empty bladder). Two individualized strategies were designed: a nonadaptive strategy, using an mbITV accounting for the full-range of bladder volume changes throughout the treatment; and an online-adaptive strategy, using mbITVs of bladder volume subranges to construct a library of plans. The latter adapts the treatment online by selecting the plan-of-the-day from the library based on the measured bladder volume. The individualized strategies were evaluated by the seven to eight CT scans not used for mbITVs construction, and compared with a population-based approach. Geometric uniform margins around planning cervix-uterus and mbITVs were determined to ensure adequate coverage. For each strategy, the percentage of the cervix-uterus, bladder, and rectum volumes inside the planning target volume (PTV), and the clinical target volume (CTV)-to-PTV volume (volume difference between PTV and CTV) were calculated. RESULTS The margin for the population-based approach was 38 mm and for the individualized strategies was 7 to 10 mm. Compared with the population-based approach, the individualized nonadaptive strategy decreased the CTV-to-PTV volume by 48% ± 6% and the percentage of bladder and rectum inside the PTV by 5% to 45% and 26% to 74% (p < 0.001), respectively. Replacing the individualized nonadaptive strategy by an online-adaptive, two-plan library further decreased the percentage of bladder and rectum inside the PTV (0% to 10% and -1% to 9%; p < 0.004) and the CTV-to-PTV volume (4-96 ml). CONCLUSIONS Compared with population-based margins, an individualized PTV results in better organ-at-risk sparing. Online-adaptive radiotherapy further improves organ-at-risk sparing.

Clinical Implementation of an Online Adaptive Plan-of-the-Day Protocol for Nonrigid Motion Management in Locally Advanced Cervical Cancer IMRT

PURPOSE To evaluate the clinical implementation of an online adaptive plan-of-the-day protocol for nonrigid target motion management in locally advanced cervical cancer intensity modulated radiation therapy (IMRT). METHODS AND MATERIALS Each of the 64 patients had four markers implanted in the vaginal fornix to verify the position of the cervix during treatment. Full and empty bladder computed tomography (CT) scans were acquired prior to treatment to build a bladder volume-dependent cervix-uterus motion model for establishment of the plan library. In the first phase of clinical implementation, the library consisted of one IMRT plan based on a single model-predicted internal target volume (mpITV), covering the target for the whole pretreatment observed bladder volume range, and a 3D conformal radiation therapy (3DCRT) motion-robust backup plan based on the same mpITV. The planning target volume (PTV) combined the ITV and nodal clinical target volume (CTV), expanded with a 1-cm margin. In the second phase, for patients showing >2.5-cm bladder-induced cervix-uterus motion during planning, two IMRT plans were constructed, based on mpITVs for empty-to-half-full and half-full-to-full bladder. In both phases, a daily cone beam CT (CBCT) scan was acquired to first position the patient based on bony anatomy and nodal targets and then select the appropriate plan. Daily post-treatment CBCT was used to verify plan selection. RESULTS Twenty-four and 40 patients were included in the first and second phase, respectively. In the second phase, 11 patients had two IMRT plans. Overall, an IMRT plan was used in 82.4% of fractions. The main reasons for selecting the motion-robust backup plan were uterus outside the PTV (27.5%) and markers outside their margin (21.3%). In patients with two IMRT plans, the half-full-to-full bladder plan was selected on average in 45% of the first 12 fractions, which was reduced to 35% in the last treatment fractions. CONCLUSIONS The implemented online adaptive plan-of-the-day protocol for locally advanced cervical cancer enables (almost) daily tissue-sparing IMRT.

Inter-fraction bladder filling variations and time trends for cervical cancer patients assessed with a portable 3-dimensional ultrasound bladder scanner

BACKGROUND AND PURPOSE For cervical cancer patients, bladder filling variations may result in inadequate EBRT target coverage, unless large safety margins are used. For a group of patients who received full bladder instructions, inter-fraction variations and time trends in bladder volume were quantified, and a 3D ultrasound (US) scanner was tested for on-line bladder volume measurements. METHODS AND MATERIALS For 24 patients, the bladder volume was measured with US at the time of the planning CT scan, and twice weekly during the course of RT. Comparisons of US with planning CT were used to assess the bladder scanner accuracy. Patients were treated in prone on a belly board, EPID images were acquired to correlate set-up errors with bladder filling variations. RESULTS Measured US and CT bladder volumes were strongly correlated (R = 0.97, slope 1.1 +/- 0.1). The population mean bladder volume at planning of 378 +/- 209 ml (1 SD) reduced to 109 +/- 88 ml (1 SD) in week 6, a reduction by 71% (average reduction 46 ml/week), revealing a large inter-fraction time trend. Intra-patient variation in bladder volume during RT was 168 ml (1 SD) (range 70-266 ml). Rotation around the LR axis was significantly correlated with bladder volume changes. CONCLUSIONS Despite a full bladder instruction, bladder volumes reduced dramatically during treatment, implying large time trends in target position of these patients. The portable US scanner provides a quick and reliable measurement of the bladder volume, which might assist future online treatment adaptation.

Toward an individualized target motion management for IMRT of cervical cancer based on model-predicted cervix–uterus shape and position

BACKGROUND AND PURPOSE To design and evaluate a 3D patient-specific model to predict the cervix-uterus shape and position. METHODS AND MATERIALS For 13 patients lying in prone position, 10 variable bladder filling CT-scans were acquired, 5 at planning and 5 after 40Gy. The delineated cervix-uterus volumes in 2-5 pre-treatment CT-scans were used to generate patient-specific models that predict the cervix-uterus geometry by bladder volume. Model predictions were compared to delineations, excluding those used for model construction. The prediction error was quantified by the margin required around the predicted volumes to accommodate 95% of the delineated volume and by the predicted-to-delineated surface distance. RESULTS The prediction margin was significantly smaller (average 50%) than the margin encompassing the cervix-uterus motion. The prediction margin could be decreased (from 7 to 5mm at planning and from 10 to 8mm after 40Gy) by increasing (from 2 to 5) the number of CT-scans used for the model construction. CONCLUSION For most patients, even with a model based on only two CT-scans, the prediction error was well below the margin encompassing the cervix-uterus motion. The described approach could be used to create prior to treatment, an individualized treatment strategy.

Comparison of VMAT and IMRT strategies for cervical cancer patients using automated planning

BACKGROUND AND PURPOSE In a published study on cervical cancer, 5-beam IMRT was inferior to single arc VMAT. Here we compare 9, 12, and 20 beam IMRT with single and dual arc VMAT. MATERIAL AND METHODS For each of 10 patients, automated plan generation with the in-house Erasmus-iCycle optimizer was used to assist an expert planner in generating the five plans with the clinical TPS. RESULTS For each patient, all plans were clinically acceptable with a high and similar PTV coverage. OAR sparing increased when going from 9 to 12 to 20 IMRT beams, and from single to dual arc VMAT. For all patients, 12 and 20 beam IMRT were superior to single and dual arc VMAT, with substantial variations in gain among the study patients. As expected, delivery of VMAT plans was significantly faster than delivery of IMRT plans. CONCLUSIONS Often reported increased plan quality for VMAT compared to IMRT has not been observed for cervical cancer. Twenty and 12 beam IMRT plans had a higher quality than single and dual arc VMAT. For individual patients, the optimal delivery technique depends on a complex trade-off between plan quality and treatment time that may change with introduction of faster delivery systems.

Increasing treatment accuracy for cervical cancer patients using correlations between bladder-filling change and cervix–uterus displacements: Proof of principle

PURPOSE To investigate application of pre-treatment established correlations between bladder-filling changes and cervix-uterus displacements in adaptive therapy. MATERIALS AND METHODS Thirteen cervical cancer patients participated in this prospective study. Pre-treatment, and after delivery of 40 Gy, a full bladder CT-scan was acquired, followed by voiding the bladder and acquisition of 4 other 3D scans in a 1h period with a naturally filling bladder (variable bladder filling CT-scans, VBF-scans). For the pre-treatment VBF-scans, linear correlations between bladder volume change and displacements of the tip of the uterus (ToU) and the center of mass (CoM) of markers implanted in the fornices of the vagina relative to the full bladder planning scan were established. Prediction accuracy of these correlation models was assessed by comparison with actual displacements in CT-scans, both pre-treatment and after 40 Gy. Inter-fraction ToU and marker-CoM displacements were derived from the established correlations and twice-weekly performed in-room bladder volume measurements, using a 3D ultrasound scanner. RESULTS Target displacement in VBF-scans ranged from up to 65 mm in a single direction to almost 0mm, depending on the patient. For pre-treatment VBF-scans, the linear correlation models predicted the mean 3D position change for the ToU of 26.1 mm±10.8 with a residual of only 2.2 mm±1.7. For the marker-CoM, the 8.4 mm±5.3 mean positioning error was predicted with a residual of 0.9 mm±0.7. After 40Gy, the mean ToU displacement was 26.8 mm±15.8, while prediction based on the pre-treatment correlation models yielded a mean residual error of 9.0 mm±3.7. Target positioning errors in the fractioned treatments were very large, especially for the ToU (-18.5mm±11.2 for systematic errors in SI-direction). CONCLUSIONS Pre-treatment acquired VBF-scans may be used to substantially enhance treatment precision of cervical cancer patients. Application in adaptive therapy is promising and warrants further investigation. For highly conformal (IMRT) treatments, the use of a full bladder drinking protocol results in unacceptably large systematic set-up errors.