Interstitial brachytherapy in the head and neck region: when has imaging for treatment planning to be performed?

BACKGROUND AND PURPOSE: The relation of real and virtual anatomy in 3D treatment planning is influencing the quality of a brachytherapy treatment. Aim of this study was to evaluate how far prior to plastic tube implantation for fractionated interstitial brachytherapy performed imaging is appropriate for treatment planning purposes in regard to iatrogenic, morphologic changes of anatomy. MATERIAL AND METHODS: Until April 1, 2001, 51 patients were included in this examination. Primary tumor sites were in the base of tongue (35), oro-/hypopharynx (9), floor of the mouth (4) as well as soft palate (3). Cross section imaging (MRI) in all the patients was performed before and three to six days after implantation of plastic tubes. To evaluate the morphologic alterations due to implant procedure and postimplant edema, distances were measured between two anatomically clearly defined landmarks of whom one had to be invariant to applicator implantation. RESULTS: Between two anatomical landmarks initially mean standard distances were measured: Vertebra-pharyngeal mucosa 1.46 cm, mandibular-pharyngeal wall 3.14 cm, mandibular tip-base of tongue 5.12 cm, tongue width 4.77 cm. The comparison of pre- and postimplant MRI then revealed mean distance alterations: Vertebra-pharyngeal mucosa 3.1 mm, mandibular-pharyngeal wall 4.2 mm, mandibular tip-base of tongue 5.9 mm, tongue width 6.0 mm. CONCLUSIONS: Mean applicator induced anatomic deviations between 3.1 and 6.0 mm compared to pre-implant anatomy, can severely change the target dose distribution. Basis of 3D-treatment planning therefore has to be always postimplant cross sectional imaging with adequate soft tissue depiction.     

Is VMAT beneficial for patients undergoing radiotherapy to the head and neck?

Volumetric Intensity-Modulated Arc Therapy (VMAT) offers solutions to the time consuming, higher monitor unit (MU) delivery of Intensity-Modulated Radiotherapy (IMRT) for patients undergoing radiotherapy for head and neck cancer (HNC). Thus the aim was to determine whether VMAT would be beneficial for these patients.The majority of literature was planning comparative studies with only two studies on early clinical experience. Main themes arising from literature were conformity and homogeneity, organs at risk (OAR), MU and delivery time.VMAT provides plans with similar conformity, better homogeneity and results for improved sparing of OAR compared to IMRT. Thus it is clear that VMAT would be able to match the performance of IMRT plans, with the ability to treat patients in a short space of time and less MU. There is little clinical data on the side effects of VMAT, and more is needed to further evaluate the efficacy of VMAT. Overall these are encouraging results of VMAT for patients with HNC.     

Real-time electromagnetic tracking–based treatment platform for high-dose-rate prostate brachytherapy: Clinical workflows and end-to-end validation

PurposeNew technologies were integrated into a novel treatment platform combining electromagnetically (EM) tracked catheters, a 3D ultrasound (3DUS) imaging device, and a new treatment planning system to provide a real-time prostate high-dose-rate (HDR) brachytherapy treatment system. This work defines workflows for offline CT and online 3DUS planning scenarios and preclinical end-to-end validation of the platform.Methods and MaterialsThe platform is composed of an EM-tracked stylet, a EM-tracked 3DUS probe, and an EM-tracked template guide, all used with the NDI Aurora field generator (NDI, Ontario, Canada). The treatment planning system performs continuous position and angular readings from all three EM sensors into a streamlined environment that allows for (1) contouring; (2) planning; (3) catheter insertion guidance and reconstruction; (4) QA of catheter path and tip position; and (5) exporting to an afterloader. Data were gathered on the times required for the various key steps of the 3DUS-based workflow.ResultsThe complete 3DUS-based workflow on 16-catheter implant phantoms took approximately 15 min. This time is expected to increase for actual patients. Plan generation is fast (7.6 ± 2.5s) and the initial catheter reconstruction with updated dose distribution is obtained at no (time) cost as part of the insertion process. Subsequent catheter reconstruction takes on average 10.5 ± 3.1s per catheter, representing less than 3 min for a 16-catheter implant.ConclusionsThis preclinical study suggests that EM technology could help to significantly streamline real-time US-based high-dose-rate prostate brachytherapy.     

Interstitial pulsed-dose-rate brachytherapy for head and neck cancer—Single-institution long-term results of 385 patients

PurposeTo assess the long-term results of protocol-based pulsed-dose-rate (PDR) interstitial brachytherapy (iBT) in 385 patients with head and neck cancer who underwent PDR-iBT preferably after minimal, nonmutilating surgery.Methods and MaterialsFrom 1997 to 2009, a total of 385 patients received protocol-based PDR-iBT for head and neck cancer. Brachytherapy was preceded by surgery in most of our patients (326/385, 84.7%). Altogether, 246 of 385 patients (63.9%) received iBT alone and 135 of 385 patients (36.1%) in combination with external beam radiation therapy. The analysis was done after a median followup of 63 months.ResultsThe 5-, 10-, and 15-year local relapse-free survival rates according to Kaplan–Meier test for all analyzed patients were 85.8%, 83.1%, and 80.2%, respectively. The 5-, 10-, and 15-year overall survival and disease-free survival rates were 68.9%, 52.2%, and 44.1%, and 81.3%, 79.3%, and 76.3%, respectively. For N0-/N1- vs. N2-patients, we observed significantly different 5-year local recurrence-free survival rates with values of 92.3% and 73.7%, respectively (p = 0.007). No other patient or treatment-related parameters had a significant influence on treatment results. Serious late side effects, such as soft tissue or bone necrosis, were observed in 39 of 385 patients (10.2%) and 18 of 385 patients (4.9%), respectively.ConclusionsThe PDR-iBT with 0.4–0.7 Gy each hour, 24 h per day for patients with head and neck cancer is a proven, effective, and safe treatment method with excellent long-term data.     

A prospective dose escalation trial of high-dose-rate brachytherapy boost for prostate cancer: Evidence of hypofractionation efficacy?

PURPOSE: The study aimed to evaluate mature outcomes of a Phase I/II high-dose-rate brachytherapy (HDRB) boost protocol. METHODS AND MATERIALS: We analyzed data from 88 patients with T1a-T3a, N0, M0 prostate adenocarcinoma treated on a prospective Phase I/II HDRB boost protocol of 16 (n = 47) or 20 Gy (n = 41) in four fractions, without planned androgen deprivation therapy. HDRB was added to 46 Gy of external beam radiotherapy (EBRT). Outcomes were compared to a contemporaneous retrospective cohort of 104 patients receiving 66 Gy EBRT monotherapy. The primary endpoint was freedom from biochemical failure, defined as a 2 ng/mL rise above the lowest prostate-specific antigen (PSA) (FFbFn2), whereas the American Society of Therapeutic Radiology and Oncology consensus definition (ACD) was used for comparative purposes. RESULTS: For the HDRB cohort, the overall actuarial 5-year FFbFn2 was 67.4% (95% CI: 58.2-75.5%). For the HDRB doses of 16 and 20 Gy, the 5-year FFbFn2 rates were 58.8% (95% CI: 41.9-72.5%) and 77.3% (95% CI: 64.4-88.3%), respectively (log-rank test p = 0.07). Compared to men treated with 66 Gy EBRT, using multivariate analysis, there was no significant benefit to using HDRB with the FFbFn2 outcome (p = 0.52), yet the ACD suggested a significant advantage (hazard ratio 0.50, 95% CI: 0.29-0.86, p = 0.011). There was a trend to better FFbFn2 outcomes with increasing biologically effective doses (p = 0.09), which was significant using the ACD (p = 0.0003). CONCLUSIONS: The data support HDRB boost as a potential means of dose escalation in prostate cancer. Significant findings using the ACD need to be validated with contemporary biochemical failure definitions. Prospective trials to optimize fractionation and evaluate outcomes in comparison to contemporary EBRT techniques are warranted.     

Declining brachytherapy utilization for high-risk prostate cancer—Can clinical pathways reverse the trend?

PurposeAlthough external beam radiation therapy (EBRT) plus a brachytherapy boost (BB) offers a 20% improvement in biochemical progression-free survival compared with dose-escalated EBRT alone for men with intermediate and high-risk prostate cancer, population studies show a concerning decline in BB utilization.MethodsWe modified our clinical pathway (CP) in January 2016 to indicate EBRT with BB as first-choice modality for high-risk prostate cancer, based on preliminary findings of Androgen Suppression Combined with Elective Nodal and Dose-Escalated Radiation Therapy. A retrospective review was performed on 659 patients with high-risk prostate cancer treated with definitive intent EBRT ± BB within a network of 19 sites between December 2011 and July 2017. χ² test was used to determine changes in practice pattern before vs. after CP modification.ResultsBefore CP modification, 25.2% of patients were planned for BB, compared with 45.4% afterward (p < 0.001). Among 23 nonbrachytherapist physicians, utilization of BB increased from 3.4% to 14.8% (p < 0.001) after CP modification. Among nine brachytherapists, utilization increased from 46.4% to 55.6% (p = 0.120). Among patients treated by a nonbrachytherapist who did not receive BB, the reason was physician preference in 59.7%, patient preference in 19.9%, and other in 20.4%.ConclusionBased on recent evidence suggesting improved biochemical progression-free survival with use of BB for high-risk prostate cancer, we modified our CP, after which we observed increased use of a BB across a network, especially among physicians who do not perform brachytherapy. However, physician preference remains the most significant factor in the nonutilization of BB. New mechanisms are needed to overcome this barrier.     

Intensity modulated high-dose-rate brachytherapy boost complementary to external beam radiation for intermediate- and high-risk localized prostate cancer patients--how we do it in Lübeck/Germany

The Kiel University technique of intensity modulated brachytherapy boost implantations complementary to external beam radiation used in the treatment of prostate cancer patients was improved by involving real-time three-dimensional transrectal ultrasound analysis of the prostate gland both before implantation and after the implantation but before capture of the transrectal ultrasound images for real-time dynamic treatment planning. Implantation technique, treatment planning procedure, and dose delivery are described as practiced at the University Hospital Schleswig-Holstein Campus Lübeck, Germany.     

How might financial pressures have impacted brachytherapy? A proposed narrative to explain the declines in cervical and prostate brachytherapy utilization

Rates of brachytherapy administration in the United States have declined for both cervical and prostate cancers, and we argue that the available facts suggest financial considerations are a major contributor to this issue. In this narrative, we discuss financial pressures that have existed for cervical and prostate brachytherapy and how they may have influenced their declining usage, consider other proposed influences, and provide suggestions for future research to understand the scope of the issue.     

The 15-year outcomes of high-dose-rate brachytherapy for radical dose escalation in patients with prostate cancer—A benchmark for high-tech external beam radiotherapy alone?

PurposeDose escalation using high-dose-rate brachytherapy (HDR-BT) is an established treatment method for prostate cancer. First, long-term results were previously published (specific Kiel method). This study aims to evaluate 10-/15-year outcomes of Kiel Protocol 1 (1986–1992).Methods and MaterialsConformal external beam radiotherapy (EBRT) was delivered to the pelvis (50 Gy per conventional fractionation) along with an HDR boost to the prostate amounting to a combined biologic equivalent dose in 2 Gy per fraction of 117.25 Gy (α/β = 3). The HDR-BT was performed in two fractions of 15 Gy to the peripheral zone of McNeal. The EBRT-clinical target volume covered the full pelvis. The analyzed cohort totaled 122 patients. The reported end points were overall/cancer-specific survival, local recurrence/distant metastasis rates, and biochemical (BC) control rates according to American Society for Therapeutic Radiology and Oncology/Phoenix definitions. All end points were calculated using the Kaplan–Meier method and the log-rank test in univariate analyses.ResultsThe mean follow-up time was 116.8 months. The 5-, 10-, and 15-year survival rates were 81%, 62.1%, and 45% for overall survival; 92.1%, 83.1%, and 75.3% for cancer-specific survival; 92.5%, 91.4%, and 83.9% for local recurrence–free survival; and 83.8%, 81.2%, and 69.8% for distant metastasis–free survival, respectively. American Society for Therapeutic Radiology and Oncology–defined BC tumor control rates at 5, 10, and 15 years were 81.1%, 74%, and 67.8%, respectively. According to Phoenix, the BC control rates at 5, 10, and 15 years were 77.8%, 69%, and 63.6%, respectively.ConclusionsThe long-term results for the combination of HDR-BT and EBRT continue to show excellent results, providing high equivalent dose in 2 Gy per fraction and high disease control rates. These outcomes were reproducible for the extended follow-up period ranging up to 21.9 years.     

Can ultrasound elastography distinguish metastatic from reactive lymph nodes in patients with primary head and neck cancers?

Objectives

The purpose of this study was to evaluate the diagnostic utility of real-time elastography (RTE) in differentiating between reactive and metastatic cervical lymph nodes (LN) in patients with primary head and neck cancer in comparison with the conventional B mode and power Doppler parameters.

Methods

A total of 127 lymph nodes in 78 patients with primary head and neck cancer were examined by B-mode sonography, power Doppler ultrasound and elastography. Elastographic patterns were determined on the distribution and percentage of the lymph node area with low elasticity (hard), with pattern 1 being an absent or very small hard area to pattern 5, a hard area occupying the entire lymph node. Patterns 3–5 were considered metastatic. Ultrasound guided aspiration cytology was done for 57 lymph nodes. Excision biopsy was done for 52 lymph nodes. Eighteen lymph nodes responded to conservative treatment, and were considered reactive.

Results

The majority (85.3%) of the metastatic lymph nodes had elastography pattern 3–5. This finding was observed in only 5% of the benign lymph nodes (P < 0.001). The elastography pattern had sensitivity of 85.3%, specificity of 95.5%, PPV of 97.2%, NPV of 78.1% and overall accuracy of 88.9% in differentiation between benign and malignant lymph nodes. On the other hand, for the B mode criteria, the best accuracy was given to abnormal hilum (83%). The accuracy of power Doppler ultrasound pattern was 70.8%.

Conclusions

The accuracy of sonoelastography is higher than usual B mode and power Doppler ultrasound parameters in differentiation between benign and malignant nodes. The integration of lymph node sonoelastography in the follow up of patients with known head and neck cancer may reduce the number of biopsies.     

Can FDG PET predict radiation treatment outcome in head and neck cancer? Results of a prospective study

Purpose  

In head and neck cancer (HNC) various treatment strategies have been developed to improve outcome, but selecting patients for these intensified treatments remains difficult. Therefore, identification of novel pretreatment assays to predict outcome is of interest. In HNC there are indications that pretreatment tumour ¹⁸F-fluorodeoxyglucose (FDG) uptake may be an independent prognostic factor. The aim of this study was to assess the prognostic value of FDG uptake and CT-based and FDG PET-based primary tumour volume measurements in patients with HNC treated with (chemo)radiotherapy.     

Can mammographic assessments lead to consider density as a risk factor for breast cancer?

Admitting that mammographic breast density is an important independent risk factor for breast cancer in the general population, has a crucial economical health care impact, since it might lead to increasing screening frequency or reinforcing additional modalities. Thus, the impact of density as a risk factor has to be carefully investigated and might be debated. Some authors suggested that high density would be either a weak factor or confused with a masking effect. Others concluded that most of the studies have methodological biases in basic physics to quantify percentage of breast density, as well as in mammographic acquisition parameters. The purpose of this review is to evaluate mammographic procedures and density assessments in published studies regarding density as a breast cancer risk. No standardization was found in breast density assessments and compared density categories. High density definitions varied widely from 25 to 75% of dense tissues on mammograms. Some studies showed an insufficient follow-up to reveal masking effect related to mammographic false negatives. Evaluating breast density impact needs thorough studies with consensual mammographic procedures, methods of density measurement, breast density classification as well as a standardized definition of high breast density. Digital mammography, more effective in dense breasts, should help to re-evaluate the issue of density as a risk factor for breast cancer.     

Comparison of MR imaging sequences for liver and head and neck interventions: is there a single optimal sequence for all purposes?

RATIONALE AND OBJECTIVES: To compare the appropriate pulse sequences for interventional device guidance during magnetic resonance (MR) imaging at 0.2 T and to evaluate the dependence of sequence selection on the anatomic region of the procedure. MATERIALS AND METHODS: Using a C-arm 0.2 T system, four interventional MR sequences were applied in 23 liver cases and during MR-guided neck interventions in 13 patients. The imaging protocol consisted of: multislice turbo spin echo (TSE) T2w, sequential-slice fast imaging with steady precession (FISP), a time-reversed version of FISP (PSIF), and FISP with balanced gradients in all spatial directions (True-FISP) sequences. Vessel conspicuity was rated and contrast-to-noise ratio (CNR) was calculated for each sequence and a differential receiver operating characteristic was performed. RESULTS: Liver findings were detected in 96% using the TSE sequence. PSIF, FISP, and True-FISP imaging showed lesions in 91%, 61%, and 65%, respectively. The TSE sequence offered the best CNR, followed by PSIF imaging. Differential receiver operating characteristic analysis also rated TSE and PSIF to be the superior sequences. Lesions in the head and neck were detected in all cases by TSE and FISP, in 92% using True-FISP, and in 84% using PSIF. True-FISP offered the best CNR, followed by TSE imaging. Vessels appeared bright on FISP and True-FISP imaging and dark on the other sequences. CONCLUSION: In interventional MR imaging, no single sequence fits all purposes. Image guidance for interventional MR during liver procedures is best achieved by PSIF or TSE, whereas biopsies in the head and neck are best performed using FISP or True-FISP sequences.     

Can we reduce dose to ureters as avoidance organs for MRI based brachytherapy for cervical cancer? A dosimetric feasibility study

BACKGROUND AND PURPOSEUreteral stenosis (US) is an underreported complication of brachytherapy (BT) for cervical cancer (CC), with limited data on toxicity risk reduction. A previous study demonstrated ureter EQD2 D0.1cc > 77 Gy correlated with US development. We sought to assess feasibility of this constraint while maintaining similar HR-CTV coverage.MATERIALS AND METHODSPatients with locally advanced CC treated with EBRT plus HDR MRI-based brachytherapy boost without hydronephrosis at diagnosis and with ureter dose EQD2 D0.1cc > 77 Gy were included. Replan was attempted to achieve HR-CTV D90 ≥ 80–85 Gy and ureter dose reduction. Ureter distance from lateral margin of HR-CTV and tandem was recorded. t-test was performed to compare ureteral dose and HR-CTV D90.RESULTsOf 25 patients were identified. Hundred percent received 45 Gy in 25 fractions to the pelvis ± paraaortic lymph nodes and 80% receiving median additional parametrial dose of 5.4 Gy. Replan meeting ureteral dose of ≤77 Gy was feasible in 18 of 25 patients, with a reduction in median ureter D0.1cc from 82.3 to 76.8 Gy (p < 0.001). Median HR-CTV D90 was similar (84.7 vs. 85.0 Gy). Replan achieved D0.1cc ≤77 Gy in 56% of patients who experienced US. All unilateral US cases occurred in the ureter closest to HR-CTV.CONCLUSIONSOptimization to reduce ureter dose to ≤77 Gy is feasible when ureters are visible and contoured. Ureters may be considered as potential OAR during MRI-based brachytherapy treatment. Reduced ring to tandem total reference air kerma (TRAK) ratio may provide an additional metric by which to lower US risk.     

Can radiobiological parameters derived from squamous cell carcinoma of the head and neck be used to predict local control in anal cancer treated with chemoradiation?

Objectives

Parameters have been derived in head and neck cancer to account for the additional biological effective dose provided by synchronous chemotherapy. The purpose of this study was to establish whether such parameters could be used to predict local control differences in anal cancer.

Methods

In anal cancer two randomised trials of radiotherapy vs chemoradiotherapy and two trials randomising between different synchronous chemotherapy regimens were identified. To predict differences in local control between the arms of the first two studies, a global value of 9.3 Gy for the chemotherapy biologically effective dose was employed. For the last two trials, values specific to differing chemotherapy schedules were derived. These values were added to the calculated biological effective dose for the radiotherapy component in order to predict local control outcomes in anal cancer trials.

Results

The predicted difference in local control using the global value of 9.3 Gy for the addition of synchronous chemotherapy in the trials of radiotherapy vs radiotherapy and synchronous chemotherapy was 24.6% compared with the observed difference of 21.4%. Using schedule-specific values for the contribution of chemotherapy, the predicted differences in local control in the two trials of differing synchronous chemotherapy schedules were 7.2% and 12% compared with the observed 18% and 0%.

Conclusion

The methods initially proposed require modification to result in adequate prediction. If the decreased cisplatin dose intensity employed in anal cancer is modelled, more satisfactory predictions for such trials can be achieved.

Advances in knowledge

This revised modelling may be hypothesis generating.Using radiobiological modelling in squamous cell carcinoma of the head and neck (SCCHN), parameters have been derived to account for the effects of accelerated repopulation. When these parameters are applied to published data from randomised studies comparing conventionally fractionated radiotherapy (1.8–2.0 Gy per fraction) with altered fractionations, there is a strong correlation between observed and predicted differences in local control [1]. In addition, several attempts have been made to model the additional biological effective dose (BED) contributed by the addition of synchronous chemotherapy to radiotherapy in SCCHN [2-4]. Equivalent BED for the addition of chemotherapy has also been derived for other cancers including uterine cervix, oesophagus and brain [5-8].In SCCHN, a value of 9.3 Gy additional BED (equivalent to 7.7 Gy in 2 Gy fractions) has been derived for the use of synchronous chemotherapy with conventionally fractionated radiotherapy [2]. Using this value, good correlations are seen between observed and predicted local control outcomes in randomised controlled trials of synchronous chemotherapy, provided radiotherapy is administered with conventional fractionation. This is only possible in SCCHN owing to the ability to calculate the ratio of percentage change in local control vs percentage change in BED, S_t, over the dose range of interest. This parameter has been derived in SCCHN from studies comparing conventional fractionation and altered fractionation [2].Squamous cell carcinoma (SCC) is the commonest histological type of anal cancer [9]. Anal SCC shares similar aetiological factors with SCCHN, including smoking and human papilloma virus (HPV) infection. However, no randomised controlled trials of conventional fractionation vs altered fractionation exist for anal cancer to be able to calculate the S_t for this tumour site.Therefore, the purpose of this study is to establish whether radiobiological parameters derived from SCCHN can be used to predict outcomes in terms of local control (LC) for anal SCC. This information could then be used for hypothesis generation to help develop clinical studies for both SCCHN and anal SCC.     

Time to achieve a prostate-specific antigen nadir of ≤0.2 ng/mL and related factors after permanent prostate brachytherapy

PurposeThe purpose of this study was to identify the time to achieve a prostate-specific antigen (PSA) nadir of ≤0.2 ng/mL and the related factors to achieve this goal.Materials and MethodsWe retrospectively reviewed 2218 Japanese prostate cancer patients who received ¹²⁵I brachytherapy with or without external beam radiotherapy between 2003 and 2013 at one institution. Among them, patients followed up for ≥72 months and without luteinizing hormone–releasing hormone (LH-RH) agonist/antagonist were included (total of 1089 patients). The time to a PSA nadir of ≤0.2 ng/mL (months) was defined as the time between the date of implantation and the first time the lowest PSA value reached ≤0.2 ng/mL. Biochemical recurrence (BCR) was determined using the Phoenix definition. Multivariate linear regression analysis was performed to detect the related factors to achieve this nadir.ResultsWe assigned 409, 592, and 88 patients to the low-, intermediate-risk, and high-risk groups, respectively. The median followup time was 9.5 years. The median time to achieve a PSA nadir of ≤0.2 ng/mL was 44.0 (95% confidence interval: 42.3–45.7) months. The percentage of patients that achieved the nadir was 89.1%. BCR was noted in 107 (9.8%) patients. In the multivariate analysis of patients without BCR, younger age, larger prostate volume at implantation, higher initial PSA level, and monotherapy were significantly associated with longer time to achieve the PSA nadir.ConclusionThe median time to achieve a PSA nadir of ≤0.2 ng/mL was 44.0 months. Some patients, however, may require a lengthy period of time to do so.     

Hyperfractionated accelerated radiotherapy with concomitant integrated boost of 70–75?Gy in 5?weeks for advanced head and neck cancer

Background and purpose

The present study was performed to evaluate the feasibility of a new, 5-week regimen of 70–75?Gy hyperfractionated accelerated radiotherapy with concomitant integrated boost (HARTCIB) for locally advanced, inoperable head and neck cancer.

Methods and materials

A total of 39?patients with very advanced, stage?IV nonmetastatic head and neck squamous cell carcinoma (median gross tumor volume 72?ml) were included in this phase?I dose escalation study. A total of 50?fractions intensity-modulated radiotherapy (IMRT) were administered twice daily over 5?weeks. Prescribed total dose/dose per fraction for planning target volume (PTV_tumor) were 70?Gy in 1.4?Gy fractions, 72.5?Gy in 1.45?Gy fractions, and 75?Gy in 1.5?Gy fractions for 10, 13, and 16?patients, respectively. Uninvolved lymphatic nodes (PTV_uninvolved) were irradiated with 55?Gy in 1.1?Gy fractions using the concomitant integrated boost.

Results

Acute toxicity was evaluated according to the RTOG/EORTC scale; the incidence of grade?3 mucositis was 51% in the oral cavity/pharynx and 0% in skin and the recovery time was ≤?9?weeks for all patients. Late toxicity was evaluated in patients in complete remission according to the RTOG/EORTC scale. No grade?3/4 late toxicity was observed. The 1-year locoregional progression-free survival was 50% and overall survival was 55%.

Conclusion

HARTCIB (75?Gy in 5?weeks) is feasible for patients deemed unsuitable for chemoradiation. Acute toxicity was lower than predicted from radiobiological models; duration of dysphagia and confluent mucositis were particularly short. Better conformity of radiotherapy allows the use of more intensive altered fractionation schedules compared with older studies. These results suggest that further dose escalation might be possible when highly conformal techniques (e.g., stereotactic radiotherapy) are used.     

Can DWI & ADC differentiate orbital lymphoma,non-specific orbital inflammation and orbital cellulitis?

The aim of this work

To differentiate orbital lymphoma, non-specific orbital inflammation (NSOI) and orbital cellulitis using DWI & ADC, as there is marked clinical overlap in the diagnosis of these three orbital conditions.

Material and methods

Twenty-five cases chosen from attendants of the outpatient clinic of the Ophthalmology Department of Zagazig University Hospitals with different orbital pathologies presenting with orbital inflammatory signs and/or proptosis were all examined with conventional MRI sequences then functional DWI and ADC map and values were performed.

Results

Six cases (6/25) were diagnosed as orbital lymphomas (24%), 14 cases (14/25) NSOI (formerly known as orbital inflammatory syndrome) (56%) and 5 cases (5/25) as orbital cellulitis (20%), in DWI the greater the restriction was detected in lymphomas, followed by NSOI and lastly with orbital cellulitis and ADC values ranging from 0.6 to 0.9 × 10⁻³ mm²/s for lymphoma, 1.1 to 1.3 × 10⁻³ mm²/s in NSOI and 1.5 to 1.7 × 10⁻³ mm²/s in orbital cellulitis.

Conclusion

DWI & ADC can differentiate orbital lymphoma from NSOI and orbital cellulitis and help rapid management.     

“Black bone” MRI: a potential alternative to CT when imaging the head and neck: report of eight clinical cases and review of the Oxford experience

Objective

The potential risks associated with ionising radiation are well documented. We have previously reported the “black bone” MRI sequence, useful when imaging cortical bone. The objective of this paper is to report our initial experience of this technique in patients undergoing imaging of the head and neck region.

Methods

Using the departmental database those patients having had “black bone” sequences of the head and neck performed as part of their MRI examination in the preceding 5 years were identified. The radiological reports were reviewed to identify those cases where “black bone” or conventional MRI sequences had been performed in place of the requested CT, and the patient medical records for these cases were reviewed. Medical record review was also conducted for those cases where it was considered that the pathological condition requiring imaging would ordinarily be investigated with CT.

Results

The “black bone” sequence had been performed in 69 patients as part of routine MRI of the head and neck. Of these, 67% (n=46) were performed in combination with CT imaging, the majority of cases being primary tumours. In four cases, an MRI was performed in place of the requested CT scan. We present eight clinical cases illustrating the potential benefits of the “black bone” sequence.

Conclusions

“Black bone” MRI offers a radiation-free method of imaging the head and neck, and has been successfully utilised in a range of benign and malignant conditions affecting this region.

Advances in knowledge

Adoption of this approach, where feasible, would be a significant advance in radiation protection.Hounsfield, in his 1973 paper on CT, stated that “the exposure of the patient to x-rays must be restricted” [1]. The potential risks of ionising radiation are well documented; however, we continue to fall short of Hounsfield’s advice because of increased imaging demands through a combination of defensive medicine, a decrease in exploratory surgery and the ability to meet the increased requests for CT. The largest increases in CT use have been in paediatric diagnosis and adult screening [2]. Further concern relates to the use of cone-beam CT, with scanners being installed and used in a rapidly increasing number of dental practices within the UK [3]. During the year 2002–3 the National Health Service in England [4] reported 1.7 million CT examinations, representing 8% of all X-ray examinations, and 6% of all imaging investigations. By 2009–10 this had risen to over 3.7 million: 13% and 10%, respectively. The United Nations Scientific Committee estimated that CT constitutes 5% of all X-ray examinations worldwide while accounting for about 34% of the resultant collective dose [5].The consensus among radiology professionals is that steps should be taken to reverse, or at least arrest, radiation exposure from CT [6]; yet for maxillo-cranio-facial imaging this has largely consisted of radiation reduction techniques and the introduction of cone-beam CT. The superior quality of bony imaging on CT and the ability to create three-dimensional (3D) rendered images of the craniofacial skeleton has maintained CT as the gold standard for this region.However, we have been increasingly utilising MRI when imaging the head and neck, following close collaboration between the MRI and oral and maxillofacial departments. In particular, we have previously reported the “black bone” MRI sequence for imaging cortical bone as a potential replacement for CT [7]. The technique utilises a low flip angle, with short repetition and echo times, to produce uniform contrast of the soft tissues, with densely black cortical bone. The imaging parameters are shown in