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author:("stormed, Guy")
1.  Peripheral dose heterogeneity due to the thread effect in total marrow irradiation with helical tomotherapy 
Purpose
To report potential dose heterogeneity leading to underdosing at different skeletal sites in total marrow irradiation (TMI) with helical tomotherapy due to the thread effect, and provide possible solutions to reduce this effect.
Methods and Materials
Nine cases were divided into two groups based on patientsize, defined as maximum left-to-right arm distance (mLRD): small mLRD (≤47 cm) and large mLRD (> 47 cm). TMI treatment planning was conducted by varying the pitch and modulation factor while a jaw size (5 cm) was kept fixed. Ripple amplitude, defined as the peak-to-trough dose relative to the average dose due to the thread effect, and the DVH parameters for 9 cases with various mLRD was analyzed in different skeletal regions at off-axis (e.g. bones of the arm, or femur), at the central axis (e.g. vertebrae), and PTV, defined as the entire skeleton plus 1 cm margin.
Results
Average ripple amplitude for a pitch of 0.430, known as one of the magic pitches that reduce thread effect, was 9.2% at 20 cm off-axis. No significant differences in DVH parameters of PTV, vertebrae, or femur were observed between small and large mLRD groups for a pitch of ≤0.287. Conversely, in the bones of the arm, average differences in the volume receiving 95% and 107% dose (V95, and V107, respectively) between large and small mLRD groups were 4.2% (p=0.016), and 16% (p=0.016), respectively. Strong correlations were found between mLRD and ripple amplitude (rs=0.965), mLRD and V95 (rs=−0.742), and mLRD and V107 (rs=0.870) of bones of the arm.
Conclusions
Thread effect significantly influences DVH parameters in the bones of the arm for large mLRD patients. By implementing a favorable pitch value and adjusting arm position, peripheral dose heterogeneity could be reduced.
doi:10.1016/j.ijrobp.2013.07.017
PMCID: PMC3805769  PMID: 24011657
2.  Breast Conserving Treatment for Breast Cancer: Dosimetric Comparison of Sequential versus Simultaneous Integrated Photon Boost 
BioMed Research International  2014;2014:827475.
Background. Breast conserving surgery followed by whole breast irradiation is widely accepted as standard of care for early breast cancer. Addition of a boost dose to the initial tumor area further reduces local recurrences. We investigated the dosimetric benefits of a simultaneously integrated boost (SIB) compared to a sequential boost to hypofractionate the boost volume, while maintaining normofractionation on the breast. Methods. For 10 patients 4 treatment plans were deployed, 1 with a sequential photon boost, and 3 with different SIB techniques: on a conventional linear accelerator, helical TomoTherapy, and static TomoDirect. Dosimetric comparison was performed. Results. PTV-coverage was good in all techniques. Conformity was better with all SIB techniques compared to sequential boost (P = 0.0001). There was less dose spilling to the ipsilateral breast outside the PTVboost (P = 0.04). The dose to the organs at risk (OAR) was not influenced by SIB compared to sequential boost. Helical TomoTherapy showed a higher mean dose to the contralateral breast, but less than 5 Gy for each patient. Conclusions. SIB showed less dose spilling within the breast and equal dose to OAR compared to sequential boost. Both helical TomoTherapy and the conventional technique delivered acceptable dosimetry. SIB seems a safe alternative and can be implemented in clinical routine.
doi:10.1155/2014/827475
PMCID: PMC4137720  PMID: 25162031
3.  Breast conserving treatment for breast cancer: dosimetric comparison of different non-invasive techniques for additional boost delivery 
Background
Today it is unclear which technique for delivery of an additional boost after whole breast radiotherapy for breast conserved patients should be state of the art. We present a dosimetric comparison of different non-invasive treatment techniques for additional boost delivery.
Methods
For 10 different tumor bed localizations, 7 different non-invasive treatment plans were made. Dosimetric comparison of PTV-coverage and dose to organs at risk was performed.
Results
The Vero system achieved an excellent PTV-coverage and at the same time could minimize the dose to the organs at risk with an average near-maximum-dose (D2) to the heart of 0.9 Gy and the average volume of ipsilateral lung receiving 5 Gy (V5) of 1.5%. The TomoTherapy modalities delivered an average D2 to the heart of 0.9 Gy for the rotational and of 2.3 Gy for the static modality and an average V5 to the ipsilateral lung of 7.3% and 2.9% respectively. A rotational technique offers an adequate conformity at the cost of more low dose spread and a larger build-up area. In most cases a 2-field technique showed acceptable PTV-coverage, but a bad conformity. Electrons often delivered a worse PTV-coverage than photons, with the planning requirements achieved only in 2 patients and with an average D2 to the heart of 2.8 Gy and an average V5 to the ipsilateral lung of 5.8%.
Conclusions
We present advices which can be used as guidelines for the selection of the best individualized treatment.
doi:10.1186/1748-717X-9-36
PMCID: PMC3907792  PMID: 24467916
Breast cancer; Tumor bed boost; Image guided radiation treatment (IGRT); Intensity modulated radiotherapy (IMRT); TomoTherapy; Vero
4.  A randomized hypofractionation dose escalation trial for high risk prostate cancer patients: interim analysis of acute toxicity and quality of life in 124 patients 
Background
The α/β ratio for prostate cancer is postulated being in the range of 0.8 to 2.2 Gy, giving rise to the hypothesis that there may be a therapeutic advantage to hypofractionation. To do so, we carried out a randomized trial comparing hypofractionated and conventionally fractionated image-guided intensity modulated radiotherapy (IG-IMRT) in high-risk prostate cancer. Here, we report on acute toxicity and quality of life (QOL) for the first 124 randomized patients.
Methods
The trial compares 76 Gy in 38 fractions (5 fractions/week) (Arm 1) to 63 Gy in 20 fractions (4 fractions/week) (Arm 2) (IG-IMRT). Prophylactic pelvic lymph node irradiation with 46 Gy in 23 fractions sequentially (Arm 1) and 44 Gy in 20 fractions simultaneously (Arm 2) was applied. All patients had long term androgen deprivation therapy (ADT) started before RT. Both physician-rated acute toxicity and patient-reported QOL using EPIC questionnaire are described.
Results
There were no differences in overall maximum acute gastrointestinal (GI) or genitourinary (GU) toxicity. Compared to conventional fractionation (Arm 1), GI and GU toxicity both developed significantly earlier but also disappeared earlier in the Arm 2, reaching significant differences from Arm 1 at week 8 and 9. In multivariate analyses, only parameter shown to be related to increased acute Grade ≥1 GU toxicity was the study Arm 2 (p = 0.049). There were no statistically significant differences of mean EPIC scores in any domain and sub-scales. The clinically relevant decrease (CRD) in EPIC urinary domain was significantly higher in Arm 2 at month 1 with a faster recovery at month 3 as compared to Arm 1.
Conclusions
Hypofractionation at 3.15 Gy per fraction to 63 Gy within 5 weeks was well tolerated. The GI and GU physician-rated acute toxicity both developed earlier but recovered faster using hypofractionation. There was a correlation between acute toxicity and bowel and urinary QOL outcomes. Longer follow-up is needed to determine the significance of these associations with late toxicity.
doi:10.1186/1748-717X-8-206
PMCID: PMC3846611  PMID: 24007322
5.  Health-related quality of life in survivors of stage I-II breast cancer: randomized trial of post-operative conventional radiotherapy and hypofractionated tomotherapy 
BMC Cancer  2012;12:495.
Background
Health-related quality of life (HRQOL) assessment is a key component of clinical oncology trials. However, few breast cancer trials comparing adjuvant conventional radiotherapy (CR) and hypofractionated tomotherapy (TT) have investigated HRQOL. We compared HRQOL in stage I-II breast cancer patients who were randomized to receive either CR or TT. Tomotherapy uses an integrated computed tomography scanner to improve treatment accuracy, aiming to reduce the adverse effects of radiotherapy.
Methods
A total of 121 stage I–II breast cancer patients who had undergone breast conserving surgery (BCS) or mastectomy (MA) were randomly assigned to receive either CR or TT. CR patients received 25 × 2 Gy over 5 weeks, and BCS patients also received a sequential boost of 8 × 2 Gy over 2 weeks. TT patients received 15 × 2.8 Gy over 3 weeks, and BCS patients also received a simultaneous integrated boost of 15 × 0.6 Gy over 3 weeks. Patients completed the EORTC QLQ-C30 and BR23 questionnaires. The mean score (± standard error) was calculated at baseline, the end of radiotherapy, and at 3 months and 1, 2, and 3 years post-radiotherapy. Data were analyzed by the 'intention-to-treat' principle.
Results
On the last day of radiotherapy, patients in both treatment arms had decreased global health status and functioning scores; increased fatigue (clinically meaningful in both treatment arms), nausea and vomiting, and constipation; decreased arm symptoms; clinically meaningful increased breast symptoms in CR patients and systemic side effects in TT patients; and slightly decreased body image and future perspective.
At 3 months post-radiotherapy, TT patients had a clinically significant increase in role- and social-functioning scores and a clinically significant decrease in fatigue. The post-radiotherapy physical-, cognitive- and emotional-functioning scores improved faster in TT patients than CR patients. TT patients also had a better long-term recovery from fatigue than CR patients. ANOVA with the Bonferroni correction did not show any significant differences between groups in HRQOL scores.
Conclusions
TT patients had a better improvement in global health status and role- and cognitive-functioning, and a faster recovery from fatigue, than CR patients. These results suggest that a shorter fractionation schedule may reduce the adverse effects of treatment.
doi:10.1186/1471-2407-12-495
PMCID: PMC3492203  PMID: 23098579
Health-related quality of life; Breast cancer; Hypofractionated radiotherapy; Adjuvant treatment; Randomized trial
6.  Early Contralateral Shoulder-Arm Morbidity in Breast Cancer Patients Enrolled in a Randomized Trial of Post-Surgery Radiation Therapy 
Introduction
Shoulder/arm morbidity is a common complication of breast cancer surgery and radiotherapy (RT), but little is known about acute contralateral morbidity.
Methods
Patients were 118 women enrolled in a RT trial. Arm volume and shoulder mobility were assessed before and 1–3 months after RT. Correlations and linear regression were used to analyze changes affecting ipsilateral and contralateral arms, and changes affecting relative interlimb differences (RID).
Results
Changes affecting one limb correlated with changes affecting the other limb. Arm volume between the two limbs correlated (R = 0.57). Risk factors were weight increase and axillary dissection. Contralateral and ipsilateral loss of abduction strongly correlated (R = 0.78). Changes of combined RID exceeding 10% affected the ipsilateral limb in 25% of patients, and the contralateral limb in 18%. Aromatase inhibitor therapy was significantly associated with contralateral loss of abduction.
Conclusions
High incidence of early contralateral arm morbidity warrants further investigations.
doi:10.4137/BCBCR.S9362
PMCID: PMC3418149  PMID: 22904635
early breast cancer; short-course radiation therapy; image-guided radiation therapy; shoulder/arm morbidity; breast cancer-related lymphedema
7.  Short course radiotherapy with simultaneous integrated boost for stage I-II breast cancer, early toxicities of a randomized clinical trial 
Background
TomoBreast is a unicenter, non-blinded randomized trial comparing conventional radiotherapy (CR) vs. hypofractionated Tomotherapy (TT) for post-operative treatment of breast cancer. The purpose of the trial is to compare whether TT can reduce heart and pulmonary toxicity. We evaluate early toxicities.
Methods
The trial started inclusion in May 2007 and reached its recruitment in August 2011. Women with stage T1-3N0M0 or T1-2N1M0 breast cancer completely resected by tumorectomy (BCS) or by mastectomy (MA) who consented to participate were randomized, according to a prescribed computer-generated randomization schedule, between control arm of CR 25x2 Gy/5 weeks by tangential fields on breast/chest wall, plus supraclavicular-axillary field if node-positive, and sequential boost 8x2 Gy/2 weeks if BCS (cumulative dose 66 Gy/7 weeks), versus experimental TT arm of 15x2.8 Gy/3 weeks, including nodal areas if node-positive and simultaneous integrated boost of 0.6 Gy if BCS (cumulative dose 51 Gy/3 weeks). Outcomes evaluated were the pulmonary and heart function. Comparison of proportions used one-sided Fisher's exact test.
Results
By May 2010, 70 patients were randomized and had more than 1 year of follow-up. Out of 69 evaluable cases, 32 were assigned to CR (21 BCS, 11 MA), 37 to TT (20 BCS, 17 MA). Skin toxicity of grade ≥1 at 2 years was 60% in CR, vs. 30% in TT arm. Heart function showed no significant difference for left ventricular ejection fraction at 2 years, CR 4.8% vs. TT 4.6%. Pulmonary function tests at 2 years showed grade ≥1 decline of FEV1 in 21% of CR, vs. 15% of TT and decline of DLco in 29% of CR, vs. 7% of TT (P = 0.05).
Conclusions
There were no unexpected severe toxicities. Short course radiotherapy of the breast with simultaneous integrated boost over 3 weeks proved feasible without excess toxicities. Pulmonary tests showed a slight trend in favor of Tomotherapy, which will need confirmation with longer follow-up of patients.
Trail registration
ClinicalTrials.gov NCT00459628
doi:10.1186/1748-717X-7-80
PMCID: PMC3432009  PMID: 22656865
Early breast cancer; Hypofractionation; Simultaneous integrated boost (SIB); Image guided radiation treatment (IGRT); Intensity modulated radiotherapy (IMRT)
8.  Scapula alata in early breast cancer patients enrolled in a randomized clinical trial of post-surgery short-course image-guided radiotherapy 
Background
Scapula alata (SA) is a known complication of breast surgery associated with palsy of the serratus anterior, but it is seldom mentioned. We evaluated the risk factors associated with SA and the relationship of SA with ipsilateral shoulder/arm morbidity in a series of patients enrolled in a trial of post-surgery radiotherapy (RT).
Methods
The trial randomized women with completely resected stage I-II breast cancer to short-course image-guided RT, versus conventional RT. SA, arm volume and shoulder-arm mobility were measured prior to RT and at one to three months post-RT. Shoulder/arm morbidities were computed as a post-RT percentage change relative to pre-RT measurements.
Results
Of 119 evaluable patients, 13 (= 10.9%) had pre-RT SA. Age younger than 50 years old, a body mass index less than 25 kg/m2, and axillary lymph node dissection were significant risk factors, with odds ratios of 4.8 (P = 0.009), 6.1 (P = 0.016), and 6.1 (P = 0.005), respectively. Randomization group was not significant. At one to three months’ post-RT, mean arm volume increased by 4.1% (P = 0.036) and abduction decreased by 8.6% (P = 0.046) among SA patients, but not among non-SA patients. SA resolved in eight, persisted in five, and appeared in one patient.
Conclusion
The relationship of SA with lower body mass index suggests that SA might have been underestimated in overweight patients. Despite apparent resolution of SA in most patients, pre-RT SA portended an increased risk of shoulder/arm morbidity. We argue that SA warrants further investigation. Incidentally, the observation of SA occurring after RT in one patient represents the second case of post-RT SA reported in the literature.
doi:10.1186/1477-7819-10-86
PMCID: PMC3488523  PMID: 22591589
Breast cancer; Surgery; Radiation treatment; Complications; Winged scapula; Scapular winging; Long thoracic nerve; Multiple outcomes; Shoulder/arm morbidity; Lymphedema
9.  Phase II study of helical tomotherapy in the multidisciplinary treatment of oligometastatic colorectal cancer 
Background
Complete metastasectomy provides a real chance for long-term survival in patients with oligometastatic colorectal cancer (CRC). For inoperable patients, we evaluated in this study intensity-modulated and image-guided radiotherapy (IMRT-IGRT) by helical tomotherapy.
Methods
Twenty-four CRC patients with ≤ 5 metastases were enrolled, receiving a dose of 50 Gy in fractions of 5 Gy. No limitations concerning dimension or localization of the metastases were imposed. Whole body PET-CT was performed at baseline and 3 months after the initiation of RT to evaluate the metabolic response rate according to PET Response Criteria in Solid Tumors (PERCIST) version 1.0.
Results
A total of 53 metastases were treated. Seventeen patients (71%) received previously ≥ 1 line of chemotherapy for metastatic disease, displaying residual (n = 7) or progressive (n = 10) metabolic active oligometastatic disease at time of inclusion. Most common sites were the lung, liver and lymphnodes. One patient (4%) experienced grade 3 dysphagia. Twenty-two patients were evaluated by post-treatment PET-CT. Twelve patients achieved a complete (n = 6) or partial (n = 6) metabolic response, resulting in an overall metabolic response rate of 55%. At a median follow-up of 10 months, 7 patients (29%) are in remission, of which 5 received previous chemotherapy with residual oligometastatic disease at time of inclusion. The actuarial 1-year local control, progression-free survival, and overall survival were 54%, 14% and 78%.
Conclusions
Helical tomotherapy delivering 10 fractions of 5 Gy resulted in a metabolic response rate of 55%, and appeared to be attractive as consolidation of inoperable oligometastatic disease after effective chemotherapy.
Trial registration
Eudract 2008-008300-40; NCT00807313
doi:10.1186/1748-717X-7-34
PMCID: PMC3355052  PMID: 22423615
Metastatic colorectal cancer; Oligometastases; Helical tomotherapy; IMRT-IGRT
10.  Prognostic value of histopathology and trends in cervical cancer: a SEER population study 
BMC Cancer  2007;7:164.
Background
Histopathology is a cornerstone in the diagnosis of cervical cancer but the prognostic value is controversial.
Methods
Women under active follow-up for histologically confirmed primary invasive cervical cancer were selected from the United States Surveillance, Epidemiology, and End Results (SEER) 9-registries public use data 1973–2002. Only histologies with at least 100 cases were retained. Registry area, age, marital status, race, year of diagnosis, tumor histology, grade, stage, tumor size, number of positive nodes, number of examined nodes, odds of nodal involvement, extent of surgery, and radiotherapy were evaluated in Cox models by stepwise selection using the Akaike Information Criteria.
Results
There were 30,989 records evaluable. From 1973 to 2002, number of cases dropped from 1,100 new cases/year to 900/year, but adenocarcinomas and adenosquamous carcinoma increased from 100/year to 235/year. Median age was 48 years. Statistically significant variables for both overall and cause-specific mortality were: age, year of diagnosis, race, stage, histology, grade, hysterectomy, radiotherapy, tumor size and nodal ratio. The histological types were jointly significant, P < 0.001. Cause-specific mortality hazard ratios by histological type relatively to non-microinvasive squamous cell carcinoma were: microinvasive squamous cell carcinoma 0.28 (95% confidence interval: 0.20–0.39), carcinoma not otherwise specified 0.91 (0.79–1.04), non-mucinous adenocarcinoma 1.06 (0.98–1.15), adenosquamous carcinoma 1.35 (1.20–1.51), mucinous adenocarcinoma 1.52 (1.23–1.88), small cell carcinoma 1.94 (1.58–2.39).
Conclusion
Small cell carcinoma and adenocarcinomas were associated with poorer survival. The incidental observation of increasing numbers of adenocarcinomas despite a general decline suggests the inefficiency of conventional screening for these tumors. Increased incidence of adenocarcinomas, their adverse prognosis, and the young age at diagnosis indicate the need to identify women who are at risk.
doi:10.1186/1471-2407-7-164
PMCID: PMC1994954  PMID: 17718897
11.  The impact of radiotherapy in the treatment of desmoid tumours. An international survey of 110 patients. A study of the Rare Cancer Network 
Purpose
A multi-centre study to assess the value of combined surgical resection and radiotherapy for the treatment of desmoid tumours.
Patients and methods
One hundred and ten patients from several European countries qualified for this study. Pathology slides of all patients were reviewed by an independent pathologist. Sixty-eight patients received post-operative radiotherapy and 42 surgery only. Median follow-up was 6 years (1 to 44). The progression-free survival time (PFS) and prognostic factors were analysed.
Results
The combined treatment with radiotherapy showed a significantly longer progression-free survival than surgical resection alone (p smaller than 0.001). Extremities could be preserved in all patients treated with combined surgery and radiotherapy for tumours located in the limb, whereas amputation was necessary for 23% of patients treated with surgery alone. A comparison of PFS for tumour locations proved the abdominal wall to be a positive prognostic factor and a localization in the extremities to be a negative prognostic factor. Additional irradiation, a fraction size larger than or equal to 2 Gy and a total dose larger than 50 Gy to the tumour were found to be positive prognostic factors with a significantly lower risk for a recurrence in the univariate analysis. This analysis revealed radiotherapy at recurrence as a significantly worse prognostic factor compared with adjuvant radiotherapy. The addition of radiotherapy to the treatment concept was a positive prognostic factor in the multivariate analysis.
Conclusion
Postoperative radiotherapy significantly improved the PFS compared to surgery alone. Therefore it should always be considered after a non-radical tumour resection and should be given preferably in an adjuvant setting. It is effective in limb preservation and for preserving the function of joints in situations where surgery alone would result in deficits, which is especially important in young patients.
doi:10.1186/1748-717X-2-12
PMCID: PMC1828737  PMID: 17343751
12.  Modeling the effect of age in T1-2 breast cancer using the SEER database 
BMC Cancer  2005;5:130.
Background
Modeling the relationship between age and mortality for breast cancer patients may have important prognostic and therapeutic implications.
Methods
Data from 9 registries of the Surveillance, Epidemiology, and End Results Program (SEER) of the United States were used. This study employed proportional hazards to model mortality in women with T1-2 breast cancers. The residuals of the model were used to examine the effect of age on mortality. This procedure was applied to node-negative (N0) and node-positive (N+) patients. All causes mortality and breast cancer specific mortality were evaluated.
Results
The relationship between age and mortality is biphasic. For both N0 and N+ patients among the T1-2 group, the analysis suggested two age components. One component is linear and corresponds to a natural increase of mortality with each year of age. The other component is quasi-quadratic and is centered around age 50. This component contributes to an increased risk of mortality as age increases beyond 50. It suggests a hormonally related process: the farther from menopause in either direction, the more prognosis is adversely influenced by the quasi-quadratic component. There is a complex relationship between hormone receptor status and other prognostic factors, like age.
Conclusion
The present analysis confirms the findings of many epidemiological and clinical trials that the relationship between age and mortality is biphasic. Compared with older patients, young women experience an abnormally high risk of death. Among elderly patients, the risk of death from breast cancer does not decrease with increasing age. These facts are important in the discussion of options for adjuvant treatment with breast cancer patients.
doi:10.1186/1471-2407-5-130
PMCID: PMC1277821  PMID: 16212670
13.  Ratios of involved nodes in early breast cancer 
Breast Cancer Research  2004;6(6):R680-R688.
Introduction
The number of lymph nodes found to be involved in an axillary dissection is among the most powerful prognostic factors in breast cancer, but it is confounded by the number of lymph nodes that have been examined. We investigate an idea that has surfaced recently in the literature (since 1999), namely that the proportion of node-positive lymph nodes (or a function thereof) is a much better predictor of survival than the number of excised and node-positive lymph nodes, alone or together.
Methods
The data were abstracted from 83,686 cases registered in the Surveillance, Epidemiology, and End Results (SEER) program of women diagnosed with nonmetastatic T1–T2 primary breast carcinoma between 1988 and 1997, in whom axillary node dissection was performed. The end-point was death from breast cancer. Cox models based on different expressions of nodal involvement were compared using the Nagelkerke R2 index (R2N). Ratios were modeled as percentage and as log odds of involved nodes. Log odds were estimated in a way that avoids singularities (zero values) by using the empirical logistic transform.
Results
In node-negative cases both the number of nodes excised and the log odds were significant, with hazard ratios of 0.991 (95% confidence interval 0.986–0.997) and 1.150 (1.058–1.249), respectively, but without improving R2N. In node-positive cases the hazard ratios were 1.003–1.088 for the number of involved nodes, 0.966–1.005 for the number of excised nodes, 1.015–1.017 for the percentage, and 1.344–1.381 for the log odds. R2N improved from 0.067 (no nodal covariate) to 0.102 (models based on counts only) and to 0.108 (models based on ratios).
Discussion
Ratios are simple optimal predictors, in that they provide at least the same prognostic value as the more traditional staging based on counting of involved nodes, without replacing them with a needlessly complicated alternative. They can be viewed as a per patient standardization in which the number of involved nodes is standardized to the number of nodes excised. In an extension to the study, ratios were validated in a comparison with categorized staging measures using blinded data from the San Jose–Monterey cancer registry. A ratio based prognostic index was also derived. It improved the Nottingham Prognostic Index without compromising on simplicity.
doi:10.1186/bcr934
PMCID: PMC1064081  PMID: 15535850
axillary lymph node ratio; breast neoplasm; functional form; loco-regional; log odds; nodal ratio; Nottingham Prognostic Index; predictive utility; prognostic factors; proportional hazards; proportion based; ratio-based prognostic index; SEER program; staging; survival

Results 1-13 (13)