Influence of Using a Contrast-Enhanced CT Image as the Primary Image on CyberKnife Brain Radiosurgery Treatment Plans

Background and PurposeThis study aimed to quantify the differences between pre- and post-contrast agent (CA) CT for CyberKnife brain SRS plans.Materials and MethodsTwenty-five patients were retrospectively analyzed. They were divided into two categories, inhomogeneous cases (13 patients) and homogeneous cases (12 patients), according to whether the tumor was close to the cavity and inhomogeneous tissues or not. The pre-CA and post-CA plans were designed and calculated using the same monitor unit and paths as those in the ray-tracing algorithm, respectively.ResultsThe CT number difference of tumor between pre- and post-CA was significant (on average, 24.78 ± 18.56 HU, P-value < 0.01). The deviation value of the target was the largest at approximately 37 HU (inhomo-) and 13 HU (homo-) (P < 0.01), and the values of the organs at risk (OARs) were not statistically significant (P-value > 0.05). However, it was not statistically significant for the dose difference between the two groups with the injection of CA (P-value > 0.05). The absolute effective depth difference generally remained at a level of 1 mm, but the dose difference was quitely fluctuated sometimes more than 20%. The absolute effective depth difference of the inhomo-case (0.62 mm) was larger than that of the homo-case (0.37 mm) on median, as well as the variation amplitude (P-value < 0.05). Moreover, the relative dose differences between the two cases were 0.38% (inhomo-) and 0.2% (homo-), respectively (P-value < 0.05). At the criterion of 1 mm/1%, the gamma pass rate of the homo-case (95.89%) was larger than that of the inhomo-case (93.79%). For the OARs, except for the cochlea, the two cases were almost the same (>98.85%). The tumor control probability of the target was over 99.99% before and after injection of a CA, as well as the results for the homo-case and inhomo-case.ConclusionsConsidering the difference of evaluation indexes between pre- and post-CA images, we recommended plain CT to be employed as the primary image for improving the CK treatment accuracy of brain SRS, especially when the target was close to CA-sensitive OARs and cavity.

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Multi-factorial considerations for intra-thoracic lymph node evaluations of healthy cats on computed tomographic images

BMC Veterinary Research ◽

10.1186/s12917-021-02771-7 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Ninlawan Thammasiri ◽

Chutimon Thanaboonnipat ◽

Nan Choisunirachon ◽

Damri Darawiroj

Keyword(s):

Lymph Node ◽

Lymph Nodes ◽

Ct Images ◽

Slice Thickness ◽

Maximum Width ◽

Post Contrast ◽

Computed Tomographic ◽

Contrast Enhanced Ct ◽

Contrast Enhanced ◽

Enhanced Ct

Abstract Background It is difficult to examine mild to moderate feline intra-thoracic lymphadenopathy via and thoracic radiography. Despite previous information from computed tomographic (CT) images of intra-thoracic lymph nodes, some factors from animals and CT setting were less elucidated. Therefore, this study aimed to investigate the effect of internal factors from animals and external factors from the CT procedure on the feasibility to detect the intra-thoracic lymph nodes. Twenty-four, client-owned, clinically healthy cats were categorized into three groups according to age. They underwent pre- and post-contrast enhanced CT for whole thorax followed by inter-group evaluation and comparison of sternal, cranial mediastinal, and tracheobronchial lymph nodes. Results Post contrast-enhanced CT appearances revealed that intra-thoracic lymph nodes of kittens were invisible, whereas the sternal, cranial mediastinal, and tracheobronchial nodes of cats aged over 7 months old were detected (6/24, 9/24 and 7/24, respectively). Maximum width of these lymph nodes were 3.93 ± 0.74 mm, 4.02 ± 0.65 mm, and 3.51 ± 0.62 mm, respectively. By age, lymph node sizes of these cats were not significantly different. Transverse lymph node width of males was larger than that of females (P = 0.0425). Besides, the detection score of lymph nodes was affected by slice thickness (P < 0.01) and lymph node width (P = 0.0049). Furthermore, an irregular, soft tissue structure, possibly the thymus, was detected in all juvenile cats and three mature cats. Conclusions Despite additional information on intra-thoracic lymph nodes in CT images, which can be used to investigate lymphatic-related abnormalities, age, sex, and slice thickness of CT images must be also considered.

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Investigation of whether in-room CT-based adaptive intracavitary brachytherapy for uterine cervical cancer is robust against interfractional location variations of organs and/or applicators

Journal of Radiation Research ◽

10.1093/jrr/rrw043 ◽

2016 ◽

Vol 57 (6) ◽

pp. 677-683 ◽

Cited By ~ 1

Author(s):

Yoshifumi Oku ◽

Hidetaka Arimura ◽

Tran Thi Thao Nguyen ◽

Yoshiyuki Hiraki ◽

Masahiko Toyota ◽

...

Keyword(s):

Cervical Cancer ◽

Radiation Treatment ◽

Organs At Risk ◽

Normal Tissue Complication Probability ◽

Uterine Cervical Cancer ◽

Intracavitary Brachytherapy ◽

Conformity Index ◽

Tumor Control ◽

Tumor Control Probability ◽

Target Volumes

Abstract This study investigates whether in-room computed tomography (CT)-based adaptive treatment planning (ATP) is robust against interfractional location variations, namely, interfractional organ motions and/or applicator displacements, in 3D intracavitary brachytherapy (ICBT) for uterine cervical cancer. In ATP, the radiation treatment plans, which have been designed based on planning CT images (and/or MR images) acquired just before the treatments, are adaptively applied for each fraction, taking into account the interfractional location variations. 2D and 3D plans with ATP for 14 patients were simulated for 56 fractions at a prescribed dose of 600 cGy per fraction. The standard deviations (SDs) of location displacements (interfractional location variations) of the target and organs at risk (OARs) with 3D ATP were significantly smaller than those with 2D ATP (P < 0.05). The homogeneity index (HI), conformity index (CI) and tumor control probability (TCP) in 3D ATP were significantly higher for high-risk clinical target volumes than those in 2D ATP. The SDs of the HI, CI, TCP, bladder and rectum D2cc, and the bladder and rectum normal tissue complication probability (NTCP) in 3D ATP were significantly smaller than those in 2D ATP. The results of this study suggest that the interfractional location variations give smaller impacts on the planning evaluation indices in 3D ATP than in 2D ATP. Therefore, the 3D plans with ATP are expected to be robust against interfractional location variations in each treatment fraction.

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Feasibility and safety of percutaneous computed tomography guided radiofrequency ablation of lymph nodes in oligometastatic patients: a single center’s experience

British Journal of Radiology ◽

10.1259/bjr.20200445 ◽

2021 ◽

Vol 94 (1121) ◽

pp. 20200445

Author(s):

Dimitrios Filippiadis ◽

George Charalampopoulos ◽

Athanasios Tsochatzis ◽

Lazaros Reppas ◽

Argyro Mazioti ◽

...

Keyword(s):

Radiofrequency Ablation ◽

Lymph Nodes ◽

Clinical Success ◽

Complete Response ◽

Tumor Control ◽

Complication Rates ◽

Ct Guided ◽

Female Ratio ◽

Contrast Enhanced Ct ◽

The Mean

Objectives: To retrospectively evaluate feasibility and safety of CT-guided percutaneous radiofrequency ablation (RFA) of metastatic lymph nodes (LN) in terms of achieving local tumor control. Methods: Institutional database research identified 16 patients with 24 metastatic LNs who underwent percutaneous CT-guided radiofrequency ablation. Mean patient age was 66.6 ± 15.70 years (range 40–87) and male/female ratio was 8/8. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics and RFA technique were evaluated. Technical and clinical success on per tumor and per patient basis as well as complication rates were recorded. Results: Mean size of the treated nodes was 1.78 ± 0.83 cm. The mean number of tumors per patient was 1.5 ± 0.63. The mean procedure time was 56.29 ± 24.27 min including local anesthesia, electrode(s) placement, ablation and post-procedural CT evaluation. Median length of hospital stay was 1.13 ± 0.34 days. On a per lesion basis, the overall complete response post-ablation according to the mRECIST criteria applied was 75% (18/24) of evaluable tumors. Repeat treatment of an index tumor was performed on two patients (three lesions) with complete response achieved in 87.5% (21/24) of evaluable tumors following a second RFA. On a per patient basis, disease progression was noted in 10/16 patients at a mean of 13.9 ± 6.03 months post the ablation procedure. Conclusion: CT-guided percutaneous RFA for oligometastatic LNs is a safe and feasible therapy. Advances in knowledge: With this percutaneous therapeutic option, metastatic LNs can be eradicated with a very low complication rate.

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The Use of Ultrasound Imaging in the External Beam Radiotherapy Workflow of Prostate Cancer Patients

BioMed Research International ◽

10.1155/2018/7569590 ◽

2018 ◽

Vol 2018 ◽

pp. 1-16 ◽

Cited By ~ 11

Author(s):

Saskia M. Camps ◽

Davide Fontanarosa ◽

Peter H. N. de With ◽

Frank Verhaegen ◽

Ben G. L. Vanneste

Keyword(s):

Prostate Cancer ◽

Cancer Patients ◽

Ultrasound Imaging ◽

Organs At Risk ◽

External Beam Radiotherapy ◽

Treatment Options ◽

Current Status ◽

Tumor Control ◽

External Beam ◽

Image Guided Radiotherapy

External beam radiotherapy (EBRT) is one of the curative treatment options for prostate cancer patients. The aim of this treatment option is to irradiate tumor tissue, while sparing normal tissue as much as possible. Frequent imaging during the course of the treatment (image guided radiotherapy) allows for determination of the location and shape of the prostate (target) and of the organs at risk. This information is used to increase accuracy in radiation dose delivery resulting in better tumor control and lower toxicity. Ultrasound imaging is harmless for the patient, it is cost-effective, and it allows for real-time volumetric organ tracking. For these reasons, it is an ideal technique for image guidance during EBRT workflows. Review papers have been published in which the use of ultrasound imaging in EBRT workflows for different cancer sites (prostate, breast, etc.) was extensively covered. This new review paper aims at providing the readers with an update on the current status for prostate cancer ultrasound guided EBRT treatments.

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Reply to A. Roy and A. Apparao by author

Geophysics ◽

10.1190/1.1486651 ◽

1978 ◽

Vol 43 (6) ◽

pp. 1276-1276

Author(s):

L. S. Edwards

Keyword(s):

Spacing Factor ◽

Effective Depth ◽

The Absolute

The calculation of absolute effective depth for any finite, realizable array can be based on the total array length L or on any other spacing factor desired. The burden of the discussion by Roy and Apparao is that the distance a between the active electrodes is the natural spacing factor for the 2‐pole array. I agree entirely with this, as evidenced by my statement that “the absolute effective depth is almost directly proportional to a”, and by my inclusion of [Formula: see text] coefficients in the first column of Table 2. I would consider the factors of this column to be the natural units for depth calculations for all arrays (except for the Schlumberger and gradient arrays, where L or the conventional L/2 is more suitable).

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Spine Stereotactic Body Radiotherapy: Indications, Outcomes, and Points of Caution

Global Spine Journal ◽

10.1177/2192568217694016 ◽

2017 ◽

Vol 7 (2) ◽

pp. 179-197 ◽

Cited By ~ 38

Author(s):

Chia-Lin Tseng ◽

Wietse Eppinga ◽

Raphaele Charest-Morin ◽

Hany Soliman ◽

Sten Myrehaug ◽

...

Keyword(s):

Minimally Invasive ◽

Stereotactic Body Radiotherapy ◽

Organs At Risk ◽

Spinal Metastases ◽

Response Assessment ◽

Tumor Control ◽

Spinal Instability ◽

Minimally Invasive Techniques ◽

Stereotactic Radiation ◽

Invasive Techniques

Study Design: A broad narrative review. Objectives: The objective of this article is to provide a technical review of spine stereotactic body radiotherapy (SBRT) planning and delivery, indications for treatment, outcomes, complications, and the challenges of response assessment. The surgical approach to spinal metastases is discussed with an overview of emerging minimally invasive techniques. Methods: A comprehensive review of the literature was conducted on the techniques, outcomes, and developments in SBRT and surgery for spinal metastases. Results: The optimal management of patients with spinal metastases is complex and requires multidisciplinary assessment from an oncologic team that is familiar with the shifting paradigm as a consequence of evolving techniques in surgery and stereotactic radiation, as well as new developments in systemic agents. The Spinal Instability Neoplastic Score and the epidural spinal cord compression (Bilsky) grading system are useful tools that facilitate communication among oncologic team members and can direct management by providing a baseline assessment of risks prior to therapy. The combined multimodality approach with “separation surgery” followed by postoperative spine SBRT achieves thecal sac decompression, improves tumor control, and avoids complications that may be associated with more extensive surgery. Conclusion: Spine SBRT is a highly effective treatment that is capable of delivering ablative doses to the target while sparing the critical organs-at-risk, chiefly the critical neural tissues, within a short and manageable schedule. At the same time, surgery occupies an important role in select patients, particularly with the expanding availability and expertise in minimally invasive techniques. With rapid adoption of spine SBRT in centers outside of the academic setting, it is imperative for the practicing oncologist to understand the relevance and application of these evolving concepts.

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Negative effects of iodine-based contrast agent on renal function in patients with moderate reduced renal function hospitalized for COVID-19

BMC Nephrology ◽

10.1186/s12882-021-02469-w ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Anna Kistner ◽

Chen Tamm ◽

Ann Mari Svensson ◽

Mats O. Beckman ◽

Fredrik Strand ◽

...

Keyword(s):

Renal Failure ◽

Renal Function ◽

Renal Replacement Therapy ◽

Replacement Therapy ◽

Contrast Administration ◽

Post Contrast ◽

Contrast Enhanced Ct ◽

Contrast Enhanced ◽

Enhanced Ct ◽

Ct Contrast

Abstract Background Kidney disease and renal failure are associated with hospital deaths in patients with COVID − 19. We aimed to test if contrast enhancement affects short-term renal function in hospitalized COVID − 19 patients. Methods Plasma creatinine (P-creatinine) was measured on the day of computed tomography (CT) and 24 h, 48 h, and 4–10 days after CT. Contrast-enhanced (n = 142) and unenhanced (n = 24) groups were subdivided, based on estimated glomerular filtration rates (eGFR), > 60 and ≤ 60 ml/min/1.73 m2. Contrast-induced acute renal failure (CI-AKI) was defined as ≥27 μmol/L increase or a > 50% rise in P-creatinine from CT or initiation of renal replacement therapy during follow-up. Patients with renal replacement therapy were studied separately. We evaluated factors associated with a > 50% rise in P-creatinine at 48 h and at 4–10 days after contrast-enhanced CT. Results Median P-creatinine at 24–48 h and days 4–10 post-CT in patients with eGFR> 60 and eGFR≥30–60 in contrast-enhanced and unenhanced groups did not differ from basal values. CI-AKI was observed at 48 h and at 4–10 days post contrast administration in 24 and 36% (n = 5/14) of patients with eGFR≥30–60. Corresponding figures in the eGFR> 60 contrast-enhanced CT group were 5 and 5% respectively, (p < 0.037 and p < 0.001, Pearson χ2 test). In the former group, four of the five patients died within 30 days. Odds ratio analysis showed that an eGFR≥30–60 and 30-day mortality were associated with CK-AKI both at 48 h and 4–10 days after contrast-enhanced CT. Conclusion Patients with COVID − 19 and eGFR≥30–60 had a high frequency of CK-AKI at 48 h and at 4–10 days after contrast administration, which was associated with increased 30-day mortality. For patients with eGFR≥30–60, we recommend strict indications are practiced for contrast-enhanced CT. Contrast-enhanced CT had a modest effect in patients with eGFR> 60.

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Integrating Evidence-Based Medicine for Treatment of Spinal Metastases Into a Decision Framework: Neurologic, Oncologic, Mechanicals Stability, and Systemic Disease

Journal of Clinical Oncology ◽

10.1200/jco.2017.72.7362 ◽

2017 ◽

Vol 35 (21) ◽

pp. 2419-2427 ◽

Cited By ~ 48

Author(s):

Ori Barzilai ◽

Ilya Laufer ◽

Yoshiya Yamada ◽

Daniel S. Higginson ◽

Adam M. Schmitt ◽

...

Keyword(s):

Organs At Risk ◽

Systemic Disease ◽

Spinal Metastases ◽

Current Evidence ◽

Tumor Control ◽

High Dose ◽

Mechanical Instability ◽

Decision Framework ◽

Clear Trend ◽

Definitive Therapy

Patients with cancer are frequently affected by spinal metastases. Treatment is palliative, with the principle goals of pain relief, preservation of neurologic function, and improvement in quality of life. In the past decade, we have witnessed a dramatic change in the treatment paradigms due to the development of improved surgical strategies and systemic and radiation therapy. The most important change to these paradigms has been the integration of spinal stereotactic radiosurgery (SSRS), allowing delivery of tumoricidal radiation doses with sparing of nearby organs at risk. High-dose SSRS provides durable tumor control when used either as definitive therapy or as a postoperative adjuvant therapy. Integration of SSRS has fundamentally changed the indications for and type of surgery performed for metastatic spine tumors. Although the role for surgical intervention is well established, a clear trend toward less-aggressive, often minimally invasive techniques has been observed. Targeted therapies are also rapidly changing the way cancer is being treated and have demonstrated improved survival for a number of malignancies. As these treatment decisions become more complex, a multidisciplinary approach including medical oncologists, radiation oncologists, surgeons, interventionalists, and pain specialists is required. In this article, the current evidence affecting the treatment of spinal metastases is integrated into a decision framework that considers four principal assessments of a patient’s spine disease: NOMS (neurologic, oncologic, mechanical instability, and systemic disease).

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Dose prescription in SBRT for early-stage non-small cell lung cancer: are we all speaking the same language?

Tumori Journal ◽

10.1177/0300891620929425 ◽

2020 ◽

pp. 030089162092942

Author(s):

Anna Merlotti ◽

Pierluigi Bonomo ◽

Riccardo Ragona ◽

Marco Trovò ◽

Filippo Alongi ◽

...

Keyword(s):

Dose Distribution ◽

Early Stage ◽

Organs At Risk ◽

Optimal Dose ◽

Target Volume ◽

Local Tumor Control ◽

Oncologic Outcomes ◽

Tumor Control ◽

Distribution Data ◽

Published Data

Introduction: Stereotactic body radiation therapy is increasingly used in the treatment of early-stage lung cancers. Guidelines provide indications regarding the constraints to the organs at risk (OARs) and the minimum coverage of the planning target volume but do not suggest optimal dose distribution. Data on dose distribution from the different published series are not comparable due to different prescription modalities and reported dose parameters. Methods: We conducted a review of the published data on dose prescription, focusing on the role of homogeneity on local tumor control, and present suggestions on how to specify and report the prescriptions to permit comparisons between studies or between cases from different centers. Conclusions: To identify the dose-prescription modality that better correlates with oncologic outcomes, future studies should guarantee a close uniformity of dose distribution between cases and complete dose parameters reporting for treatment volumes and OARs.

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Tumor response assessment in locally unresectable or metastatic soft tissue sarcoma (aSTS) patients (pts): A three-year Regina Elena Cancer Institute (IRE) experience with trabectedin therapy.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.e21517 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. e21517-e21517

Author(s):

Carmen Nuzzo ◽

Vincenzo Anelli ◽

Silvia Carpano ◽

Angela Torsello ◽

Domenico Sergi ◽

...

Keyword(s):

Tumor Response ◽

Previous Treatment ◽

Response Assessment ◽

Median Number ◽

Ct Images ◽

Tumor Control ◽

Small Series ◽

Contrast Enhanced Ct ◽

Contrast Enhanced ◽

Enhanced Ct

e21517 Background: Trabectedin has emerged as an effective agent for aSTS pts pretreated with anthracyclines and ifosfamide. Recent data suggest that RECIST criteria could underestimate tumor response. Methods: ASTS pts who received trabectedin as 2nd or further line of treatment were retrospectively reviewed. Tumor response was assessed using RECIST, mChoi and MASS criteria. A good response according to mChoi Criteria was defined as ≥ 10% mean decrease in tumor size or a ≥ 15% decrease in tumor attenuation on contrast-enhanced CT images. Predominantly solid enhancing target lesions were evaluated for marked central necrosis or marked decreased attenuation on axial contrast-enhanced CT images by MASS Criteria. Results: From May 2009 to December 2012, 30 pts with aSTS received trabectedin; pts characteristics are summarized in the table. Median number of previous treatment lines was 2 (range 1-5); median number of cycles administered was 4 (range 1–22 cycles). Treatment was well tolerated; main causes of dose-reduction were hematological and liver toxicities. Median progression free survival (PFS) was 8 wks (95% CI: 2-14); median overall survival (OS) was 44 wks (95% CI: 18-94). According to RECIST, 4 pts (15.4%)obtained a partial response (PR)), 9 pts (34.6%) achieved a stable disease (SD); tumor control rate was 50%. 13 pts (43%) obtained a progression of disease (PD). CT Scans of 13 pts were available for comparison of different response assessment methods (2 RP, 5 SD, and 6 PD). In our small series of pts concordance between the three radiologic methods tested was 90%. Conclusions: In aSTS patients treated with trabectedin, there is substantial concordance between mChoi, MASS and RECIST criteria. Prospective validation of the potential role of mChoi and MASS criteria in this setting is warranted. [Table: see text]

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