Whole-body magnetic resonance imaging in the detection of skeletal metastases in patients with prostate cancer.


Whole-body MRI is an effective method for evaluating the entire skeletal system in patients with metastatic disease. This study aimed to compare whole-body MRI and radionuclide bone scintigraph in the detection of skeletal metastases in patients with prostate cancer. Patients with prostate cancer at high risk of skeletal metastasis with (i) prostate-specific antigen of ≥50 ng/mL; (ii) composite Gleason score of ≥8 with prostate-specific antigen of >20 ng/mL; or (iii) node-positive disease were enrolled in this prospective study before systemic treatment was initiated. Whole-body MR images and bone scans of 39 patients were analysed. Seven patients had bone metastases on bone scans, while seven patients had skeletal metastases by whole-body MRI, with concordant findings only in four patients. Compared with the ‘gold standard’, derived from clinical and radiological follow-up, the sensitivity for both bone scans and MRI was 70%, and the specificity for both was 100%. Magnetic resonance imaging detected 26 individual lesions compared with 18 lesions on bone scans. Only eight lesions were positive on both. Bone scans detected more rib metastases, while MRI identified more metastatic lesions in the spine. Whole-body MRI and radionuclide bone scintigraphy have similar specificity and sensitivity and may be used as complementary investigations to detect skeletal metastases from prostate cancer.

Source: Journal of Medical Imaging and Radiation Oncology

 

Patterns of failure for glioblastoma multiforme following concurrent radiation and temozolomide


Purpose: To analyse patterns of failure in patients with glioblastoma multiforme treated with concurrent radiation and temozolomide.

Materials and Methods: A retrospective review of patients treated with concurrent radiation and temozolomide was performed. Twenty patients treated at the University of Alabama at Birmingham, with biopsy-proven disease, documented disease progression after treatment, and adequate radiation dosimetry and imaging records were included in the study. Patients generally received 46 Gy to the primary tumour and surrounding oedema plus 1 cm, and 60 Gy to the enhancing tumour plus 1 cm. MRIs documenting failure after therapy were fused to the original treatment plans. Contours of post-treatment tumour volumes were generated from MRIs showing tumour failure and were overlaid onto the original isodose curves. The recurrent tumours were classified as in-field, marginal or regional. Recurrences were also evaluated for distant failure.

Results: Of the 20 documented failures, all patients had some component of failure at the primary site. Eighteen patients (90%) failed in-field, 2 patients (10%) had marginal failures, and no regional failures occurred. Four patients (20%) had a component of distant failure in which an independent satellite lesion was located completely outside of the 95% isodose curve.

Conclusions: Radiation concurrent with temozolomide appears to be associated with a moderate risk of distant brain failure in addition to the high rate of local failure. The risk of distant failure was consistent with that observed with radiation alone, suggesting that temozolomide does not act to reduce distant brain failure but to improve local control.

Source: Journal of Medical Imaging and Radiation Oncology

 

Adding Prednisolone to Standard Immunoglobulin Treatment Is Beneficial in High-Risk Kawasaki Disease.


The beneficial effects of adding prednisolone are impressive in this randomized study.

Kawasaki disease (KD) is an acute systemic vasculitis in children that might result in coronary artery aneurysms. In a multicenter randomized trial, researchers examined the efficacy of adding prednisolone to standard treatment with intravenous (IV) immunoglobulin and aspirin in 248 children in Japan with severe KD: 123 patients received standard treatment, and 125 children received standard treatment plus IV prednisolone (2 mg/kg/day) for at least 5 days followed by tapered doses of oral prednisolone. A risk score was used to identify patients at high risk for a lack of response to initial treatment with IV immunoglobulin based on serum sodium concentrations <133 mmol/L, 4 days of illness at diagnosis, aspartate aminotransferase concentrations 100 U/L, 80% neutrophils, platelet counts 30 x 104/µL, C-reactive protein concentrations 100 mg/L, and age <12 months. Patients received prednisolone for a mean of 21 days.

At 4 weeks, the incidence of coronary artery abnormalities detected by echocardiography was significantly lower in the prednisolone group than in the standard-treatment group (3% vs. 23%). The z scores of all major coronary arteries, duration of fever, and need for additional immunoglobulin rescue treatments were all significantly lower in the prednisolone group. Adverse events were rare in the two groups.

Comment: The efficacy of corticosteroid treatment for KD has been controversial, and previous study results were conflicting. An editorialist notes that the longer duration of prednisolone therapy and the highly selected group of patients might account for differences in outcome. The added beneficial effects of prednisolone demonstrated in this study are impressive. Therefore, early treatment with immunoglobulin, aspirin, and prednisolone should be considered in selected high-risk patients to further reduce the risk for coronary artery aneurysms. Unfortunately, the risk score used to identify high-risk patients with KD in Japan has not been validated in patients in North America.

Source: Journal Watch Pediatrics and Adolescent Medicine.

Effect of radiation therapy on the latest generation of pacemakers and implantable cardioverter defibrillators: A systematic review.


The increasing human lifespan and development of technology over the last number of decades has seen an increase in the number of pacemaker and implantable cardioverter defibrillator (ICD) implantations worldwide. Given the number of risk factors common to both heart disease and cancer, it is not uncommon for several of these patients to present for radiation therapy treatment each year. A systematic review was conducted using online databases Medline and Scopus. Results were grouped into in vitro and in vivo studies. In 1994, the American Association of Physicists in Medicine (AAPM) defined guidelines for the management of these patients, which have since been adopted by many radiation oncology departments internationally. More recently, a number of studies have reported an increase in radiation sensitivity of these devices (encompassing the coiled metal leads and generator unit) due to the incorporation of complementary metal oxide semiconductor circuitry. Further avenues of device failure, such as the effect of dose rate and scatter radiation, have only more recently been investigated. There are also the unexplored avenues of electromagnetic interference on devices when incorporating newer treatment technologies such as respiratory gating and intensity modulated radiation therapy. It is suggested that each radiation oncology department employ a policy for the management of patients with ICDs and pacemakers, potentially based upon an updated national or international standard similar to that released by the AAPM in 1994.

Source: Journal of Medical Imaging and Radiation Oncology

 

Management of skin toxicity during radiation therapy: A review of the evidence.


Acute skin toxicity occurs in the majority of the patients undergoing radical radiotherapy. While a variety of topical agents and dressing are used to ameliorate side effects, there is minimal evidence to support their use. The aims of this study were to systematically review evidence on acute skin toxicity management and to assess the current practices in ANZ. A systematic review of the literature was conducted on studies published between 1980 and 2008. A meta-analysis was performed on articles on clinical trials reporting grade II or greater toxicity. Analyses were divided into breast (the most common site) and other sites. A survey of Radiation Oncology departments across ANZ was conducted to identify patterns of practices and compare these with the published evidence. Twenty-nine articles were reviewed. Only seven articles demonstrated statistically significant results for management of side-effects. These were for topical corticosteroids, hyaluronic acid, sucralfate, calendula, Cavilon cream (3M, St Paul, Minnesota, USA) and silver leaf dressing. Meta-analysis demonstrated statistical significance for the prophylactic use of topical agents in the management acute toxicity. The survey of departments had a low response rate but demonstrated variation in skin care practices across ANZ. A considerable number of these practices were based only on anecdotal evidence. Lack of evidence in the literature for the care of radiation skin reactions was associated with variation in practice. Only a limited number of studies have demonstrated a significant benefit of specific topical agents. There is a need for objective and prospective recording of skin toxicity to collect meaningful comparative data on which to base recommendations for practice.

Source: Journal of Medical Imaging and Radiation Oncology

 

Clinical care and technical recommendations for 90yttrium microsphere treatment of liver cancer.


Selective internal radiation therapy (SIRT) with 90yttrium microspheres is a relatively new clinical modality for treating non-resectable malignant liver tumours. This interventional radiology technique employs percutaneous microcatheterisation of the hepatic arterial vasculature to selectively deliver radioembolic microspheres into neoplastic tissue. SIRT results in measurable tumour responses or delayed disease progression in the majority of eligible patients with hepatocellular carcinoma or hepatic metastases arising from colorectal cancer. It has also been successfully used as palliative therapy for non-colorectal malignancies metastatic to the liver. Although most adverse events are mild and transient, SIRT also carries some risks for serious and – rarely – fatal outcomes. In particular, entry of microspheres into non-target vessels may result in radiation-induced tissue damage, such as severe gastric ulceration or radiation cholecystitis. Radiation-induced liver disease poses another significant risk. By careful case selection, considered dose calculation and meticulous angiographic technique, it is possible to minimise the incidence of such complications to less than 10% of all treatments. As the number of physicians employing SIRT expands, there is an increasing need to consolidate clinical experience and expertise to optimise patient outcomes. Authored by a panel of clinicians experienced in treating liver tumours via SIRT, this paper collates experience in vessel mapping, embolisation, dosimetry, microsphere delivery and minimisation of non-target delivery. In addition to these clinical recommendations, the authors propose institutional criteria for introducing SIRT at new centres and for incorporating the technique into multidisciplinary care plans for patients with hepatic neoplasms.

Source: Journal of Medical Imaging and Radiation Oncology

 

Enlarged hilar and mediastinal lymph nodes in chronic obstructive pulmonary disease.


To evaluate the frequency of enlarged hilar or mediastinal lymph nodes in patients suffering from chronic obstructive pulmonary disease (COPD).

Methods:  In a retrospective study, 89 patients with proven COPD were analysed. Exclusion criteria were history of malignant disease or clinical evidence of pneumonia. Prevalence, size, and localisation of enlarged lymph nodes were assessed by multi-slice computed tomography (MSCT) and correlated with the clinical stages following the GOLD classification as well as the MSCT findings of bronchitis and emphysema.

Results:  44/89 (49%) of our patients showed enlarged lymph nodes. Lymph node enlargement was more often seen in the mediastinum (48%) than the hilar region (20%). The most common localisation of enlarged mediastinal lymph nodes was the regional station 7 following the ATS mapping (infracarinal). Patients with a stage I following the GOLD classification showed enlarged lymph nodes in 49% (18/37), stage II in 46% (12/26), stage III in 58% (7/12) and stage IV in 50% (7/14). These findings did not differ significantly (P > 0.05). Severe airway wall thickening (42/89) was significantly more often associated with an increase of nodal enlargement (64%) (P < 0.05).

Conclusion:  The present study demonstrates that enlarged hilar and mediastinal lymph nodes may occur in a rather high percentage of patients suffering from COPD, especially in those with the MSCT finding of severe bronchitis.

Source: Journal of Medical Imaging and Radiation Oncology

 

Offline adaptive radiotherapy for bladder cancer using cone beam computed tomography.


We investigated if an adaptive radiotherapy approach based on cone beam CT (CBCT) acquired during radical treatment was feasible and resulted in improved dosimetric outcomes for bladder cancer patients compared to conventional planning and treatment protocol. A secondary aim was to compare a conventional plan with a theoretical online process where positioning is based on soft tissue position on a daily basis and treatment plan choice is based on bladder size. A conventional treatment plan was derived from a planning CT scan in the radical radiotherapy of five patients with muscle invasive bladder cancer. In this offline adaptive protocol using CBCT, the patients had 10 CBCT: daily CBCT for the first five fractions and then CBCT scan on a weekly basis. The first five daily CBCT in each patient were used to create a single adaptive plan for treatment from fraction eight onwards. A different process using the planning CT and the first five daily CBCT was used to create small, average and large bladder volumes, giving rise to small, average and large adaptive bladder treatment plans, respectively. In a retrospective analysis using the CBCT scans, we compared the clinical target volume (CTV) coverage using three protocols: (i) conventional; (ii) offline adaptive; and (iii) online adaptive with choice of ‘plan of the day’. Daily CBCT prolonged treatment time by an average of 7 min. Two of the five patients demonstrated such variation in CTV that an offline adaptive plan was used for treatment after the first five CBCT. Comparing the offline adaptive plan with the conventional plan, the CTV coverage improved from a minimum of 60.1 to 94.7% in subsequent weekly CBCT. Using the CBCT data, modelling an online adaptive protocol showed that coverage of the CTV by the 95% prescribed dose line by small, medium and large adaptive plans were 34.9, 67.4 and 90.7% of occasions, respectively. More normal tissue was irradiated using a conventional CTV to planning target volume margin (1.5 cm) compared to an online adaptive process (0.5 cm). An offline adaptive strategy improves dose coverage in certain patients to the CTV and results in a higher conformity index compared to conventional planning. Further research in online adaptive radiation therapy for bladder cancer is indicated.

Source: Journal of Medical Imaging and Radiation Oncology

 

Pregnancy and radiotherapy: Management options for minimising risk, case series and comprehensive literature review.


This article reviews the efficacy and safety of radiotherapy in patients with cancer who are pregnant. Our review provided extended follow-up results in nine cases, presents a technical discussion on measures taken to minimise foetal radiation exposure and provides a comprehensive summary of the literature. Nine patients who received radiotherapy while pregnant are described. The clinical presentation and outcomes of these and 100 additional cases identified on a systematic literature review are presented. Comparisons of scattered radiation doses from three linear accelerators are presented. The average maternal follow-up in our series was 8.9 years with one patient having a recurrence of their astrocytoma. In terms of foetal outcome, there were one death in utero, one elective termination of pregnancy and one on which no data were available. Six children, on whom long-term follow-up (average 10.3 years) was obtainable, were in good health. Overall, there had been 109 cases of radiotherapy in pregnancy that met our search criteria with 13 adverse outcomes and a median follow-up of 37 months. Comparisons of three linear accelerators demonstrated significant differences in the amount of scattered radiation to the abdominal surface. In summary radiotherapy during pregnancy can be associated with a significant number of adverse outcomes. While it may be difficult for a patient not to attribute these effects to radiotherapy, it is also difficult to define the mechanisms by which radiotherapy would have caused them, if that were the case.

Source: Journal of Medical Imaging and Radiation Oncology

 

Inter-observer variability of clinical target volume delineation for bladder cancer using CT and cone beam CT.


To compare the image quality of cone beam CT (CBCT) with that of planning CT (pCT) scan, and quantify inter-observer differences in therapeutic indices based on these scans prior to the introduction of an adaptive radiation therapy protocol for bladder cancer. Four consecutive patients were selected with muscle invasive bladder cancer receiving radical dose radiation therapy. Four radiation oncologists specializing in genitourinary malignancies contoured the clinical target volume (CTV) and rectum on both a pCT and a randomly chosen CBCT of the same patient. A conformity index (CI) for CTV and the rectum was determined for both pCT and CBCT. The maximal lateral, anterior, posterior, cranial and caudal extensions of the CTV for both CT and CBCT were determined for each observer. Variation in volumes of both the CTV and rectum for both pCT and were also compared using Varian Eclipse planning software (Varian Medical Systems, Palo Alto, CA, USA). Using pCT the mean CI for the CTV was 0.79; using CBCT the mean CI for the CTV was 0.75. For the rectum, the mean CI for using CT was 0.80 and for CBCT was 0.74. Greatest variation on CBCT CTV contours was seen in the supero-inferior direction with variation up to 2.1 cm between different radiation oncologists. With the variation in CI for pCT and CBCT of the CTV and rectum (0.04 and 0.06 respectively), CBCT is not significantly inferior to the pCT in terms of inter-observer contouring variability.

Source: Journal of Medical Imaging and Radiation Oncology