Radiation-induced lung injury (RILI) encompasses any lung toxicity induced by radiation therapy (RT) and manifests acutely as radiation pneumonitis and chronically as radiation pulmonary fibrosis. ...Because most patients with thoracic and breast malignancies are expected to undergo RT in their lifetime, many with curative intent, the population at risk is significant. Furthermore, indications for thoracic RT are expanding given the advent of stereotactic body radiation therapy (SBRT) or stereotactic ablative radiotherapy (SABR) for early-stage lung cancer in nonsurgical candidates as well as oligometastatic pulmonary disease from any solid tumor. Fortunately, the incidence of serious pulmonary complications from RT has decreased secondary to advances in radiation delivery techniques. Understanding the temporal relationship between RT and injury as well as the patient, disease, and radiation factors that help distinguish RILI from other etiologies is necessary to prevent misdiagnosis. Although treatment of acute pneumonitis is dependent on clinical severity and typically responds completely to corticosteroids, accurately diagnosing and identifying patients who may progress to fibrosis is challenging. Current research advances include high-precision radiation techniques, an improved understanding of the molecular basis of RILI, the development of small and large animal models, and the identification of candidate drugs for prevention and treatment.
To investigate using quantitative imaging to assess the malignant potential of intraductal papillary mucinous neoplasms (IPMNs) in the pancreas.
Pancreatic cysts are identified in over 2% of the ...population and a subset of these, including intraductal papillary mucinous neoplasms (IPMNs), represent pre-malignant lesions. Unfortunately, clinicians cannot accurately predict which of these lesions are likely to progress to pancreatic ductal adenocarcinoma (PDAC).
We investigated 360 imaging features within the domains of intensity, texture and shape using pancreatic protocol CT images in 53 patients diagnosed with IPMN (34 "high-grade" HG and 19 "low-grade" LG) who subsequently underwent surgical resection. We evaluated the performance of these features as well as the Fukuoka criteria for pancreatic cyst resection.
In our cohort, the Fukuoka criteria had a false positive rate of 36%. We identified 14 imaging biomarkers within Gray-Level Co-Occurrence Matrix (GLCM) that predicted histopathological grade within cyst contours. The most predictive marker differentiated LG and HG lesions with an area under the curve (AUC) of .82 at a sensitivity of 85% and specificity of 68%. Using a cross-validated design, the best logistic regression yielded an AUC of 0.96 (σ = .05) at a sensitivity of 97% and specificity of 88%. Based on the principal component analysis, HG IPMNs demonstrated a pattern of separation from LG IPMNs.
HG IPMNs appear to have distinct imaging properties. Further validation of these findings may address a major clinical need in this population by identifying those most likely to benefit from surgical resection.
Better Late Than Never… Better Never Than Late Hanania, Alexander N; Ludwig, Michelle S
International journal of radiation oncology, biology, physics,
02/2019, Letnik:
103, Številka:
2
Journal Article
Diffusion-weighted magnetic resonance imaging (DWI) provides a measurement of tumor cellularity. We evaluated the potential of apparent diffusion coefficient (ADC) values obtained from post-external ...beam radiation therapy (EBRT) DWI and prior to brachytherapy (BT) to predict for complete metabolic response (CMR) in bulky cervical cancer.
Clinical and DWI (b value = 500 s/mm
) data were obtained from patients undergoing interstitial BT with high-risk clinical target volumes (HR-CTVs) > 30 cc. Volumes were contoured on co-registered T2 weighted images and 90th percentile ADC values were calculated. Patients were stratified by CMR (defined by PET-CT at three months post-BT). Relation of CMR with 90th percentile ADC values and other clinical factors (International Federation of Gynecology and Obstetrics (FIGO) stage, histology, tumor and HR-CTV size, pre-treatment hemoglobin, and age) was assessed both in univariate and multivariate logistic regression analyses. Youden's J statistic was used to identify a threshold value.
Among 45 patients, twenty-eight (62%) achieved a CMR. On univariate analysis for CMR, only 90th percentile ADC value was significant (p = 0.029) while other imaging and clinical factors were not. Borderline significant factors were HR-CTV size (p = 0.054) and number of chemotherapy cycles (p = 0.078). On multivariate analysis 90th percentile ADC (p < 0.0001) and HR-CTV size (p < 0.003) were highly significant. Patients with 90th percentile ADC values above 2.10 × 10
mm
/s were 5.33 (95% CI, 1.35-24.4) times more likely to achieve CMR.
Clinical DWI may serve to risk-stratify patients undergoing interstitial BT for bulky cervical cancer.
Scoliosis is a well-recognized complication after abdominal radiation therapy but not reported frequently after craniospinal irradiation (CSI). We examined the incidence and risk factors for ...scoliosis after CSI in long-term survivors with medulloblastoma.
The records of patients with medulloblastoma seen at one institution from 1996 to 2006 were analyzed for the use of CSI and development of scoliosis as documented on physical examination and spinal imaging.
We identified 35 children with medulloblastoma who were ≤12 years of age at time of CSI with a median 14.3 years (range, 5.8-19.3 years) of follow-up. Twenty-seven (77.1%) were male, and median age at CSI was 6.8 years (range, 2.8-12 years). The cumulative incidence of scoliosis at 15 years was 34.6%. The median time to develop scoliosis was 7.1 years (range, 5-11.7 years) after CSI. Treatment with high dose CSI (34.2-40 Gy) and presence of hemiplegia or hemiparesis were found to be risk factors for development of scoliosis.
Scoliosis is an underreported complication of photon craniospinal irradiation.
The COVID-19 pandemic presents serious challenges for brachytherapists, and in the time-sensitive case of locally advanced cervical cancer, the need for curative brachytherapy (BT) is critical for ...survival. Given the high-volume of locally advanced cervical cancer in our safety-net hospital, we developed a strategy in close collaboration with our gynecology oncology and anesthesia colleagues to allow for completely clinic-based intracavitary brachytherapy (ICBT).
This technical report will highlight our experience with the use of paracervical blocks (PCBs) and oral multimodal analgesia (MMA) for appropriately selected cervical ICBT cases, allowing for completely clinic-based treatment.
18 of 19 (95%) screened patients were eligible for in-clinic ICBT. The excluded patient had significant vaginal fibrosis. 38 of 39 intracavitary implants were successfully transitioned for entirely in-clinic treatment utilizing PCBs and oral MMA (97% success rate). One case was aborted due to inadequate analgesia secondary to a significantly delayed case start time (PO medication effect diminished). 95% of patients reported no pain at the conclusion of the procedure. The median (IQR) D
for rectum and bladder were 64.8 (58.6-70.2) Gy and 84.1 (70.9-89.4) Gy, respectively. Median (IQR) CTV high-risk D
was 88.0 (85.6-89.8) Gy.
In a multidisciplinary effort, we have successfully transitioned many ICBT cases to the clinic with the use of PCB local anesthesia and oral multimodality therapy in direct response to the current pandemic, thereby mitigating exposure risk to patients and staff as well as reducing overall health care burden.
•High interobserver variability (IoV) was observed at junctions between the prostate and one or more organs at risk.•Radiation oncologists were the most consistent group of observers, but high IoV ...was still observed in this group.•IoV demonstrated a dependence on organ size, and was highest for the external urinary sphincter.•High IoV was observed on both treatment planning MRIs and postimplant quality assessment MRIs.•Dose-volume-histogram parameters for MRI-based prostate radiotherapy are heavily influenced by IoV.
Quantifying the interobserver variability (IoV) of prostate and periprostatic anatomy delineation on prostate MRI is necessary to inform its use for treatment planning, treatment delivery, and treatment quality assessment.
Twenty five prostate cancer patients underwent MRI-based low-dose-rate prostate brachytherapy (LDRPBT). The patients were scanned with a 3D T2-weighted sequence for treatment planning and a 3D T2/T1-weighted sequence for quality assessment. Seven observers involved with the LDRPBT workflow delineated the prostate, external urinary sphincter (EUS), seminal vesicles, rectum, and bladder on all 50 MRIs. IoV was assessed by measuring contour similarity metrics, differences in organ volumes, and differences in dosimetry parameters between unique observer pairs. Measurements from a group of 3 radiation oncologists (G1) were compared against those from a group consisting of the other 4 clinical observers (G2).
IoV of the prostate was lower for G1 than G2 (Matthew’s correlation coefficient MCC, G1 vs. G2: planning–0.906 vs. 0.870, p < 0.001; postimplant–0.899 vs. 0.861, p < 0.001). IoV of the EUS was highest of all the organs for both groups, but was lower for G1 (MCC, G1 vs. G2: planning–0.659 vs. 0.402, p < 0.001; postimplant–0.684 vs. 0.398, p < 0.001). Large differences in prostate dosimetry parameters were observed (G1 maximum absolute prostate ΔD90: planning–76.223 Gy, postimplant–36.545 Gy; G1 maximum absolute prostate ΔV100: planning–13.927%, postimplant–8.860%).
While MRI is optimal in the management of prostate cancer with radiation therapy, significant interobserver variability of the prostate and external urinary sphincter still exist.
BACKGROUND
Sporadic optic pathway/hypothalamic gliomas represent a unique entity within pediatric low‐grade glioma. Despite favorable survival, location makes treatment difficult and local ...progression debilitating. This study is a longitudinal assessment of visual acuity (VA) among children treated within the last 2 decades.
METHODS
Clinical characteristics were ed for patients treated from 2000 to 2018 at Texas Children's Cancer Center in Houston. Ophthalmologic data taken at 3‐ to 6‐month intervals were examined with age‐appropriate VA metrics converted to the LogMAR (logarithm of the minimum angle of resolution) scale. Kaplan‐Meier blindness‐free survival (BFS) curves, calculated as time‐to‐bilateral functional blindness (LogMAR ≥0.8 in both eyes), were calculated for patients receiving early radiation therapy (RT; upfront or as first‐line salvage treatment) or chemotherapy (CT) and evaluated using the log‐rank test.
RESULTS
Thirty‐eight patients with a median follow‐up of 8.5 years (range, 2‐17 years) were identified. Median age at diagnosis was 3 years (interquartile range, <1‐6 years). Early RT was administered in 11 patients (29%). Twenty‐seven patients (71%) were treated primarily with CT, initiated at a median age of 3.5 years (range, <1‐11 years). Eight patients in the CT group did eventually require RT secondary to VA loss and following multiple lines of CT. Median age at RT for all patients was 11 years (range, 3‐17 years). BFS rates were 81% at 5 years and 60% at 8 years for CT and 100% at 5 and 8 years for early RT (P = .017).
CONCLUSIONS
In a contemporary cohort, early RT, defined as initial or first‐line salvage therapy, was found to have superior BFS for appropriately selected patients with sporadic optic pathway/hypothalamic gliomas.
LAY SUMMARY
Children with low‐grade brain tumors of the optic pathway generally have excellent long‐term survival; however, given the location of these tumors, there can commonly be threatened vision if the tumor grows.
Although radiation is generally deferred in children on the basis of legitimate concerns regarding the effects on the developing brain, it may represent a vision‐preserving therapy for well‐selected older patients.
The treatment paradigm for pediatric optic pathway glioma has mostly shifted from using radiation therapy (RT) as the definitive therapy to favor postponement of RT for secondary and tertiary lines of systemic therapy. Despite excellent patient survival rates, long‐term vision outcomes with chemotherapy are poor. Well‐selected older patients who receive early RT as upfront or first‐line salvage therapy retain meaningful long‐term visual acuity.
Pulmonary nodules are often discovered incidentally during CT scans performed for other reasons. While the vast majority of nodules are benign, a small percentage may represent early-stage lung ...cancer with the potential for curative treatments. With the growing use of CT for both clinical purposes and lung cancer screening, the number of pulmonary nodules detected is expected to increase substantially. Despite well-established guidelines, many nodules do not receive proper evaluation due to a variety of factors, including inadequate coordination of care and financial and social barriers. To address this quality gap, novel approaches such as multidisciplinary nodule clinics and multidisciplinary boards may be necessary. As pulmonary nodules may indicate early-stage lung cancer, it is crucial to adopt a risk-stratified approach to identify potential lung cancers at an early stage, while minimizing the risk of harm and expense associated with over investigation of low-risk nodules.
This article, authored by multiple specialists involved in nodule management, delves into the diagnostic approach to lung nodules. It covers the process of determining whether a patient requires tissue sampling or continued surveillance. Additionally, the article provides an in-depth examination of the various biopsy and therapeutic options available for malignant lung nodules. The article also emphasizes the significance of early detection in reducing lung cancer mortality, especially among high-risk populations. Furthermore, it addresses the creation of a comprehensive lung nodule program, which involves smoking cessation, lung cancer screening, and systematic evaluation and follow-up of both incidental and screen-detected nodules.
•Lung nodule evaluation is common in clinical practice.•A multidisciplinary approach is required for appropriate triaging of nodules that require invasive testing vs surveillance.•A multidisciplinary approach is needed to treat cancerous lesions.•This reviewed is authored by the relevant practitioners in thoracic tumor boards such as Interventional pulmonary, Thoracic surgery, Interventional radiology, Radiation oncology and Medical oncology.•This review also gives an overview of Lung nodule management from the larger perspective of a health care system.
•Different loss functions for developing deep learning (DL) algorithms can change prostate and organs at risk (OAR) boundaries, particularly in anatomical regions with high interobserver ...variability.•DL-based automatic segmentation algorithms exhibit high variability in similar anatomical regions as the humans who annotated the images for the DL algorithm development.•Spatial entropy maps provide an intuitive characterization of voxel-wise segmentation variability.•DL-based automatic segmentation algorithms can be more consistent than human observers in delineating the prostate and OARs on MRIs for prostate radiotherapy.•Segmentation performance of T2-weighted planning MRIs was comparable to that of T2/T1-weighted postimplant MRIs.
Comparing deep learning (DL) algorithms to human interobserver variability, one of the largest sources of noise in human-performed annotations, is necessary to inform the clinical application, use, and quality assurance of DL for prostate radiotherapy.
One hundred fourteen DL algorithms were developed on 295 prostate MRIs to segment the prostate, external urinary sphincter (EUS), seminal vesicles (SV), rectum, and bladder. Fifty prostate MRIs of 25 patients undergoing MRI-based low-dose-rate prostate brachytherapy were acquired as an independent test set. Groups of DL algorithms were created based on the loss functions used to train them, and the spatial entropy (SE) of their predictions on the 50 test MRIs was computed. Five human observers contoured the 50 test MRIs, and SE maps of their contours were compared with those of the groups of the DL algorithms. Additionally, similarity metrics were computed between DL algorithm predictions and consensus annotations of the 5 human observers’ contours of the 50 test MRIs.
A DL algorithm yielded statistically significantly higher similarity metrics for the prostate than did the human observers (H) (prostate Matthew’s correlation coefficient, DL vs. H: planning–0.931 vs. 0.903, p < 0.001; postimplant–0.925 vs. 0.892, p < 0.001); the same was true for the 4 organs at risk. The SE maps revealed that the DL algorithms and human annotators were most variable in similar anatomical regions: the prostate-EUS, prostate-SV, prostate-rectum, and prostate-bladder junctions.
Annotation quality is an important consideration when developing, evaluating, and using DL algorithms clinically.
PDF
