How does deep learning/machine learning perform in comparison to radiologists in distinguishing glioblastomas (or grade IV astrocytomas) from primary CNS lymphomas?: a meta-analysis and systematic review

BACKGROUND

Several studies have been published comparing deep learning (DL)/machine learning (ML) to radiologists in differentiating PCNSLs from GBMs with equivocal results. We aimed to perform this meta-analysis to evaluate the diagnostic accuracy of ML/DL versus radiologists in classifying PCNSL versus GBM using MRI.

METHODOLOGY

The study was performed in accordance with PRISMA guidelines. Data was extracted and interpreted by two researchers with 12 and 23 years' experience, respectively, and QUADAS-2 tool was used for quality and risk-bias assessment. We constructed contingency tables to derive sensitivity, specificity accuracy, summary receiver operating characteristic (SROC) curve, and the area under the curve (AUC).

RESULTS

Our search identified 11 studies, of which 8 satisfied our inclusion criteria and restricted the analysis in each study to reporting the model showing highest accuracy, with a total sample size of 1159 patients. The random effects model showed a pooled sensitivity of 0.89 [95% CI:0.84-0.92] for ML and 0.82 [95% CI:0.76-0.87] for radiologists. Pooled specificity was 0.88 [95% CI: 0.84-0.91] for ML and 0.90 [95% CI: 0.81-0.95] for radiologists. Pooled accuracy was 0.88 [95% CI: 0.86-0.90] for ML and 0.86 [95% CI: 0.78-0.91] for radiologists. Pooled AUC of ML was 0.94 [95% CI:0.92-0.96]and for radiologists, it was 0.90 [95% CI: 0.84-0.93].

CONCLUSIONS

MRI-based ML/DL techniques can complement radiologists to improve the accuracy of classifying GBMs from PCNSL, possibly reduce the need for a biopsy, and avoid any unwanted neurosurgical resection of a PCNSL.

Evaluation of an Objective MRI-Based Tumor Regression Grade (mrTRG) Score and a Subjective Likert Score for Assessing Treatment Response in Locally Advanced Rectal Cancers-A Retrospective Study

Purpose:  Magnetic resonance imaging (MRI) with the help of MRI-based tumor regression grade (mrTRG) score has been used as a tool to predict pathological tumor regression grade (pTRG) in patients of rectal cancer post-neoadjuvant chemoradiation. Our study aims to evaluate the ability of MRI in assessing treatment response comparing an objective mrTRG score and a subjective Likert score, with a focus on the ability to predict pathologic complete response (pCR). Methods:  Post-treatment MRI studies were retrospectively reviewed for 170 consecutive cases of histopathologically proven rectal cancer after receiving neoadjuvant chemoradiation and prior to surgery by two oncoradiologists blinded to the eventual postoperative histopathology findings. An objective (mrTRG) and a subjective Likert score were assigned to all the cases. Receiver operating characteristic curves were constructed to determine the ability of Likert scale and mrTRG to predict pCR, with postoperative histopathology being the gold standard. The optimal cutoff points on the scale of 1 to 5 were obtained for mrTRG and Likert scale with the greatest sum of sensitivity and specificity using the Youden Index. Results:  The most accurate cutoff point for the mrTRG to predict complete response was 2.5 (using Youden index), with a sensitivity of 69.2%, specificity of 69.6%, positive predictive value (PPV) of 85.6%, negative predictive value (NPV) of 46.4%, and accuracy of 69.3%. The most accurate cutoff for the Likert scale to predict complete response was 3.5, with a sensitivity of 47.5%, specificity of 89.1%, PPV of 91.9%, NPV of 39.4%, and accuracy of 59%. mrTRG had a lower cutoff and was more accurate in predicting pCR compared to Likert score. Conclusion:  An objective mrTRG was more accurate than a subjective Likert scale to predict complete response in our study.

MRI in rectal cancer patients on 'watch and wait': patterns of response and their evolution

PURPOSE

Evaluate MR patterns of response and their evolution in rectal cancer patients on watch and wait (WW).

METHODS

We retrospectively reviewed 337 MRIs of 60 patients (median follow-up: 12 months; range: 6-49 months). Baseline MRIs (available in 34/60 patients) were evaluated for tumor morphology, location, thickness, circumferential involvement, nodal status and EMVI. First post-treatment MRIs (in all patients) were additionally evaluated for pattern of response on T2 and DWI. Change in post-treatment scar thickness and scar depth angle between the first and second post-treatment scans was also evaluated. Evolution of the response pattern/recurrence were evaluated till the last available scan.

RESULTS

On the baseline scans, 20/34 (59%) patients had polypoidal tumor with 12/20 having ≤ 25% circumferential wall involvement. We saw five patterns of response-normalized rectal wall (2/60-3%), minimal fibrosis (23/60-38%), full thickness fibrosis (16/60-27%), irregular fibrosis (11/60-18%) and split scar (6/60-10%), with 2/60 (3%) showing possible residual disease. On the first post-treatment scans, 12/60 (20%) had restricted diffusion, with 3/12 having persistent restriction till last follow-up. Post-treatment fibrosis/split scar remained stable in 44/60 (73%) cases and improved further in the rest. 9/60 (15%) patients developed regrowth/recurrence. Patients with recurrence had < 10 mm scar thickness and < 21° change in scar angle between the first and second post-treatment MRIs.

CONCLUSION

Most patients on WW protocol developed minimal or full thickness fibrosis, majority of which remained stable on follow-up.

CT Based Tumor Radiomics with Machine Learning Classifiers for Molecular Subtyping of Diffuse Large B Cell Lymphoma

PURPOSE/OBJECTIVE(S)

Diffuse large B-cell lymphoma (DLBL) has been classified into two distinct molecular subtypes based on their cell of origin- namely germinal center B-cell-like (GCB) and activated B-cell-subtype (ABC) based on Han's algorithm. These two entities are also prognostically distinct. We assessed CT based tumor radiomic features using machine learning classifiers to distinguish the two molecular subtypes.

MATERIALS/METHODS

One hundred one patients were accrued in the study after institutional ethics committee approval. GCB subtype was diagnosed in 59 while 42 patients were ABC subtype. Lesion with maximum SUV was delineated using a semi-automated segmentation tool (3D slicer) and radiomic features were extracted using Pyradiomics. A total of 1030 features were extracted including Shape features, first, second, third, higher order and wavelet-based features. Recursive feature elimination was used for feature selection and optimal 10 features were selected. Five machine learning (ML) tools were used to build a model to sub- classify the two molecular subtypes. (Table -1) Model performance was assessed using Accuracy, Precision, Recall, F1 score and Area under curve of receiver operating characteristic curve. The models were constructed by two methods.1) A 5-fold internal cross validation strategy & 2) splitting the data into training (70%) and validation set (30%).

RESULTS

Recursive feature elimination using a random forest algorithm method was used to select 7 radiomic features. These 7 features were then used to build the model using the 5 ML classifiers. Of the five classifiers, Random Forest Classifier (RFC) using a 70:30 training: test strategy was the best performer among all the ML models, with the highest accuracy of 80%, AUC of 0.87, recall(sensitivity), f1score(specificity) & precision (Positive Predictive value; PPV) or precision of 82% respectively. When an internal 5-fold cross validation strategy was used, RFC again performed better than other ML classifiers with an accuracy of 75%, AUC of 0.80, recall of 79%, PPV of 77% and specificity of 79%.

CONCLUSION

The machine-learning based Radiomics features extracted from pre-treatment CT images can provide a simple and non-invasive method for the prediction of DLBL molecular subtypes with favorable predictive accuracy. The Random Forest Classifier was the most accurate in distinguishing GCB subtype from the ABC subtype.

Deep learning based clinico-radiological model for paediatric brain tumor detection and subtype prediction

Aim

Early diagnosis of paediatric brain tumors significantly improves the outcome. The aim is to study magnetic resonance imaging (MRI) features of paediatric brain tumors and to develop an automated segmentation (AS) tool which could segment and classify tumors using deep learning methods and compare with radiologist assessment.

Methods

This study included 94 cases, of which 75 were diagnosed cases of ependymoma, medulloblastoma, brainstem glioma, and pilocytic astrocytoma and 19 were normal MRI brain cases. The data was randomized into training data, 64 cases; test data, 21 cases and validation data, 9 cases to devise a deep learning algorithm to segment the paediatric brain tumor. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the deep learning model were compared with radiologist's findings. Performance evaluation of AS was done based on Dice score and Hausdorff95 distance.

Results

Analysis of MRI semantic features was done with necrosis and haemorrhage as predicting features for ependymoma, diffusion restriction and cystic changes were predictors for medulloblastoma. The accuracy of detecting abnormalities was 90%, with a specificity of 100%. Further segmentation of the tumor into enhancing and non-enhancing components was done. The segmentation results for whole tumor (WT), enhancing tumor (ET), and non-enhancing tumor (NET) have been analyzed by Dice score and Hausdorff95 distance. The accuracy of prediction of all MRI features was compared with experienced radiologist's findings. Substantial agreement observed between the classification by model and the radiologist's given classification [K-0.695 (K is Cohen's kappa score for interrater reliability)].

Conclusions

The deep learning model had very high accuracy and specificity for predicting the magnetic resonance (MR) characteristics and close to 80% accuracy in predicting tumor type. This model can serve as a potential tool to make a timely and accurate diagnosis for radiologists not trained in neuroradiology.

Ellis van creveld syndrome: Cardiac anomalies and anesthetic implications

Ellis-Van Creveld syndrome (EVC), also known as mesoectodermal dysplasia, is a rare autosomal recessive disorder with a tetrad of clinical features, comprising dwarfism, polydactyly, ectodermal dysplasia with sparse hair, hypoplastic nails and enamel, hypodontia and conical teeth and congenital heart disease (CHD). We report an 18-year-old girl with short stature and polydactyly, who got admitted to our hospital with shortness of breath on exertion for the last 2 years. On echocardiography, a partial atrioventricular canal (AV canal) defect was diagnosed, which was repaired surgically. The patient had an uneventful perioperative period.

Classifying primary central nervous system lymphoma from glioblastoma using deep learning and radiomics based machine learning approach - a systematic review and meta-analysis

Background

Glioblastoma (GBM) and primary central nervous system lymphoma (PCNSL) are common in elderly yet difficult to differentiate on MRI. Their management and prognosis are quite different. Recent surge of interest in predictive analytics, using machine learning (ML) from radiomic features and deep learning (DL) for diagnosing, predicting response and prognosticating disease has evinced interest among radiologists and clinicians. The objective of this systematic review and meta-analysis was to evaluate the deep learning &amp; ML algorithms in classifying PCNSL from GBM.

Methods

The authors performed a systematic review of the literature from MEDLINE, EMBASE and the Cochrane central trials register for the search strategy in accordance with PRISMA guidelines to select and evaluate studies that included themes of ML, DL, AI, GBM, PCNSL. All studies reporting on ML algorithms or DL that for differentiating PCNSL from GBM on MR imaging were included. These studies were further narrowed down to focus on works published between 2018 and 2021. Two researchers independently conducted the literature screening, database extraction and risk bias assessment. The extracted data was synthesised and analysed by forest plots. Outcomes assessed were test characteristics such as accuracy, sensitivity, specificity and balanced accuracy.

Results

Ten articles meeting the eligibility criteria were identified addressing use of ML and DL in training and validation classifiers to distinguish PCNSL from GBM on MR imaging. The total sample size was 1311 in the included studies. ML approach was used in 6 studies while DL in 4 studies. The lowest reported sensitivity was 80%, while the highest reported sensitivity was 99% in studies in which ML and DL was directly compared with the gold standard histopathology. The lowest reported specificity was 87% while the highest reported specificity was 100%. The highest reported balanced accuracy was 100% and the lowest was 84%.

Conclusions

Extensive search of the database revealed a limited number of studies that have applied ML or DL to differentiate PCNSL from GBM. Of the currently published studies, Both DL &amp; ML algorithms have demonstrated encouraging results and certainly have the potential to aid neurooncologists in taking preoperative decisions in the future leading to not only reduction in morbidities but also be cost effective.

Comparative study of cardiac output measurement by regional impedance cardiography and thermodilution method in patients undergoing off pump coronary artery bypass graft surgery

Background:

An ideal CO monitor should be noninvasive, cost effective, reproducible, reliable during various physiological states. Limited literature is available regarding the noninvasive CO monitoring in open chest surgeries.

Aim:

The aim of this study was to compare the CO measurement by Regional Impedance Cardiography (RIC) and Thermodilution (TD) method in patients undergoing off pump coronary artery bypass graft surgery (OPCAB).

Settings and Design:

We conducted a prospective observational comparative study of CO measurement by the noninvasive RIC method using the NICaS Hemodynamic Navigator system and the gold standard TD method using pulmonary artery catheter in patients undergoing OPCAB. A total of 150 data pair from the two CO monitoring techniques were taken from 15 patients between 40-70 years at various predefined time intervals of the surgery.

Patients and Methods:

We have tried to find out the accuracy, precision and cost effectiveness of the newer RIC technique. Mean CO, bias and precision were compared for each pair i.e.TD-CO and RIC-CO as recommended by Bland and Altman. The Sensitivity and specificity of cutoff value to predict change in TD-CO was used to create a Receiver operating characteristic or ROC curve.

Results:

Mean TD-CO values were around 4.52 ± 1.09 L/min, while mean RIC- CO values were around 4.77± 1.84 L/min. The difference in CO change was found to be statistically not significant (p value 0.667). The bias was small (-0.25). The Bland Altman plot revealed a mean difference of -0.25 litres. The RIC method had a sensitivity of 55.56 % and specificity of 33.33 % in predicting 15% change in CO of TD method and the total diagnostic accuracy was 46.67%.

Conclusion:

A fair correlation was found between the two techniques. The RIC method may be considered as a promising noninvasive, potentially low cost alternative to the TD technique of hemodynamic measurement.

Effectiveness of empiric cardioprotective therapy in patients receiving cardiotoxic chemotherapies: systematic review & bayesian network meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Cardioprotective therapies represent an important avenue to reduce these limiting toxicities, including serious heart failure (HF) events. However, due to conflicting isolated reports, the true efficacy and optimal cardioprotective therapy at the time of anticancer treatment initiation is unclear. Therefore, we undertook a network meta-analysis to elucidate the most effective therapies at cardiotoxic HF prevention.

Purpose

To determine the efficacy, and optimal cardioprotective strategy in patients receiving cardiotoxic chemotherapies.

Methods

Leveraging the MEDLINE/Pubmed, CENTRAL, and clinicaltrials.gov databases, we identified all randomized controlled trials (RCTs) investigating cardioprotective therapies from inception to November 2021. Eligible cardioprotective classes included ACEIs, ARBs, Beta-blockers, dexrazoxane (DEX), statins, and mineralocorticoid receptor antagonists (MRA). The primary endpoint was the prevention of new-onset HF. The secondary outcomes were the mean difference in left ventricular ejection fraction (LVEF) change, the incidence of hypotension, and all-cause mortality. Network meta-analyses were used to assess the cardioprotective effects of each therapy to deduce the most effective therapies. Both analyses were undertaken using a Bayesian random-effects model to estimate risk ratios (RR) and 95% credible intervals (95% CrI).

Results

Overall, from 726 articles, 39 studies evaluating 5,931 participants (38.0±19.1 years, 72.0% females) were identified. Over a median follow-up of 6 months, use of any cardioprotective strategy was associated with a significant reduction in new-onset HF (RR:0.32; 95% CrI:0.19-0.55), improved LVEF (mean difference: 3.92%; 95% CrI:2.81-5.07), and increased hypotension (RR:3.27; 95% CrI:1.38-9.87); there was no difference in mortality (RR:1.03; 95% CrI:0.84-1.22). Based on the median risk of incident HF in the control groups being 3.28%, the number need to treat (NNT) for "any" cardioprotective therapy to prevent one incident HF event was 45 patients. For dexrazoxane and neurohormonal agents, the median NNT was 36 and 53 patients, respectively. In this network analysis, dexrazoxane was most effective at HF prevention [Surface Under the Cumulative Ranking curve (SUCRA): 81.47%] and MRA most effective at preserving LVEF (SUCRA: 99.22%). ARBs most greatly increased hypotension (RR:7.20; 95% CrI:2.46-26.94).

Conclusion

Cardiotoxicity remains a challenge for cancer patients requiring life-saving cancer therapies. The initiation of a cardioprotective strategy reduces incident HF. Additional head-to-head trials are needed to confirm the optimal preventative strategy.

Imaging for Plasma Cell Dyscrasias: What, When, and How?

Imaging plays a vital role in the diagnosis, response assessment, and follow-up of patients with plasma cell bone disease. The radiologic diagnostic paradigm has thus far evolved with developing technology and availability of better imaging platforms; however, the skewed availability of these imaging modalities in developed vis-à-vis the developing countries along with the lack of uniformity in reporting has led to a consensus on the imaging criteria for diagnosing and response assessment in plasma cell dyscrasia. Therefore, it is imperative for not only the radiologists but also the treating oncologist to be aware of the criteria and appropriate imaging modality to be used in accordance with the clinical question. The review will allow the treating oncologist to answer the following questions on the diagnostic, prognostic, and predictive abilities of various imaging modalities for plasma cell dyscrasia: a) What lesions can look like multiple myeloma (MM) but are not?; b) Does the patient have MM? To diagnose MM in a high-risk SMM patient with clinical suspicion, which modality should be used and why?; c) Is the patient responding to therapy on follow-up imaging once treatment is initiated?; d) To interpret commonly seen complications post-therapy, when is it a disease and when is the expected sequel to treatment? Fractures, red marrow reconversion?; and e) When is the appropriate time to flag a patient for further workup when interpreting MRI spine done for back pain in the elderly? How do we differentiate between commonly seen osteoporosis-related degenerative spine versus marrow infiltrative disorder?

Radiomic Analysis of Tumour Heterogeneity Using MRI in Head and Neck Cancer Following Chemoradiotherapy: A Feasibility Study

Objectives

To evaluate interval changes in heterogeneity on diffusion-weighted apparent diffusion coefficient (ADC) maps and T1-weighted post-gadolinium (T1w post gad) MRI in head and neck carcinoma (HNSCC), with and without chemo-radiotherapy (CRT) response.

Methods

This prospective observational cohort study included 24 participants (20 men, age 62.9 ± 8.8 years) with stage III and IV HNSCC. The primary tumour (n = 23) and largest lymph node (n = 22) dimensions, histogram parameters and grey-level co-occurrence matrix (GLCM) parameters were measured on ADC maps and T1w post gad sequences, performed pretreatment and 6 and 12 weeks post CRT. The 2-year treatment response at primary and nodal sites was recorded. The Wilcoxon signed-rank test was used to compare interval changes in parameters after stratifying for treatment response and failure (p < 0.001 statistical significance).

Results

23/23 primary tumours and 18/22 nodes responded to CRT at 2 years. Responding HNSCC demonstrated a significant interval change in ADC histogram parameters (kurtosis, coefficient of variation, entropy, energy for primary tumour; kurtosis for nodes) and T1w post gad GLCM (entropy and contrast in the primary tumour and nodes) by 6 weeks post CRT (p < 0.001). Lymph nodes with treatment failure did not demonstrate an interval alteration in heterogeneity parameters.

Conclusions

ADC maps and T1w post gad MRI demonstrate the evolution of heterogeneity parameters in successfully treated HNSCC by 6 weeks post CRT; however, this is not observed in lymph nodes failing treatment.

Advances in Knowledge

Early reduction in heterogeneity is demonstrated on MRI when HNSCC responds to CRT.

A rare case of cardiac hydatid cyst

Hydatid infection of the heart is rare and there is always the lethal hazard of cyst perforation. We present an 18-year-old male from Kashmir valley who was admitted to the emergency department of our hospital with fever and chest pain for the last 4 days. Using echocardiography and cardiac tomography (CT), cardiac Echinococcosis was diagnosed. The results of surgical treatment of cardiac Echinococcosis were better than the conservative strategy. Surgical excision was performed. The patient had an uneventful recovery.

Demographics, Pattern of Care, and Outcome Analysis of Malignant Melanomas - Experience From a Tertiary Cancer Centre in India

Background

Treatment of malignant melanoma has undergone a paradigm shift with the advent of immune checkpoint inhibitors (ICI) and targeted therapies. However, access to ICI is limited in low-middle income countries (LMICs).

Patients and Methods

Histologically confirmed malignant melanoma cases registered from 2013 to 2019 were analysed for pattern of care, safety, and efficacy of systemic therapies (ST).

Results

There were 659 patients with a median age of 53 (range 44–63) years; 58.9% were males; 55.2% were mucosal melanomas. Most common primary sites were extremities (36.6%) and anorectum (31.4%). Nearly 10.8% of the metastatic cohort were BRAF mutated. Among 368 non-metastatic patients (172 prior treated, 185 de novo, and 11 unresectable), with a median follow-up of 26 months (0–83 months), median EFS and OS were 29.5 (95% CI: 22–40) and 33.3 (95% CI: 29.5–41.2) months, respectively. In the metastatic cohort, with a median follow up of 24 (0–85) months, the median EFS for BSC was 3.1 (95% CI 1.9–4.8) months versus 3.98 (95% CI 3.2–4.7) months with any ST (HR: 0.69, 95% CI: 0.52–0.92; P = 0.011). The median OS was 3.9 (95% CI 3.3–6.4) months for BSC alone versus 12.0 (95% CI 10.5–15.1) months in any ST (HR: 0.38, 95% CI: 0.28–0.50; P < 0.001). The disease control rate was 51.55%. Commonest grade 3–4 toxicity was anemia with chemotherapy (9.5%) and ICI (8.8%). In multivariate analysis, any ST received had a better prognostic impact in the metastatic cohort.

Conclusions

Large real-world data reflects the treatment patterns adopted in LMIC for melanomas and poor access to expensive, standard of care therapies. Other systemic therapies provide meaningful clinical benefit and are worth exploring especially when the standard therapies are challenging to administer.

Cardiovascular adverse events are associated with usage of immune checkpoint inhibitors in real-world clinical data across the United States

Background

Immune checkpoint inhibitors (ICIs) can cause life-threatening cardiovascular adverse events (CVAEs) that may not be attributed to therapy. The outcomes of clinical trials may underestimate treatment-related adverse events due to restrictive eligibility, limited sample size, and failure to anticipate selected toxicities. We evaluated the incidence and clinical determinants of CVAEs in real-world population on ICI therapy.

Patients and methods

Among 2 687 301 patients diagnosed with cancer from 2011 to 2018, 16 574 received ICIs for any cancer. Patients in the ICI and non-ICI cohorts were matched in a 1 : 1 ratio according to age, sex, National Cancer Institute comorbidity score, and primary cancer. The non-ICI cohort was stratified into patients who received chemotherapy (N = 2875) or targeted agents (N = 4611). All CVAEs, non-cardiac immune-related adverse events occurring after treatment initiation, baseline comorbidities, and treatment details were identified and analyzed using diagnosis and billing codes.

Results

Median age was 61 and 65 years in the ICI and non-ICI cohorts, respectively (P < 0.001). ICI patients were predominantly male (P < 0.001). Lung cancer (43.1%), melanoma (30.4%), and renal cell carcinoma (9.9%) were the most common cancer types. CVAE diagnoses in our dataset by incidence proportion (ICI cohort) were stroke (4.6%), heart failure (3.5%), atrial fibrillation (2.1%), conduction disorders (1.5%), myocardial infarction (0.9%), myocarditis (0.05%), vasculitis (0.05%), and pericarditis (0.2%). Anti-cytotoxic T-lymphocyte-associated protein 4 increased the risk of heart failure [versus anti-programmed cell death protein 1; hazard ratio (HR), 1.9; 95% confidence interval (CI) 1.27-2.84] and stroke (HR, 1.7; 95% CI 1.3-2.22). Pneumonitis was associated with heart failure (HR, 2.61; 95% CI 1.23-5.52) and encephalitis with conduction disorders (HR, 4.35; 95% CI 1.6-11.87) in patients on ICIs. Advanced age, primary cancer, nephritis, and anti-cytotoxic T-lymphocyte-associated protein 4 therapy were commonly associated with CVAEs in the adjusted Cox proportional hazards model.

Conclusions

Our findings underscore the importance of risk stratification and cardiovascular monitoring for patients on ICI therapy.

•

Patient claims data across the United States were used to study cardiovascular adverse events (CVAEs) after ICI treatment.

•

Patients on ICI treatment for advanced cancer have a higher incidence of CVAEs than previously reported.

•

Median time to CVAE onset was significantly shorter with ICIs (~3 months) than with non-ICI systemic therapy (~8 months).

•

Anti-CTLA-4 monotherapy or combination had a higher risk of heart failure and stroke than anti-PD-1 therapy (1.5-2 folds).

•

Age, male sex, cancer type, nephritis, pneumonitis, and anti-CTLA-4 therapy were associated with a higher risk of CVAEs.

The impact of human papilloma virus status on the prediction of head and neck cancer chemoradiotherapy outcomes using the pre-treatment apparent diffusion coefficient

Objective:

To determine the impact of Human Papilloma Virus (HPV) oropharyngeal cancer (OPC) status on the prediction of head and neck squamous cell cancer (HNSCC) chemoradiotherapy (CRT) outcomes with pre-treatment quantitative diffusion-weighted magnetic resonance imaging (DW-MRI).

Methods:

Following ethical approval, 65 participants (53 male, age 59.9 ± 7.86) underwent pre-treatment DW-MRI in this prospective cohort observational study. There were 46 HPV OPC and 19 other HNSCC cases with Stage III/IV HNSCC. Regions of interest (ROIs) (volume, largest area, core) at the primary tumour (n = 57) and largest pathological node (n = 59) were placed to analyse ADC_mean and ADC_min. Unpaired t-test or Mann–Whitney test evaluated the impact of HPV OPC status and clinical parameters on their prediction of post-CRT 2 year locoregional and disease-free survival (LRFS and DFS). Multivariate logistic regression compared significant variables with 2 year outcomes.

Results:

On univariate analysis of all participants, the primary tumour area ADC_mean was predictive of 2 year LRFS (p = 0.04). However, only the HPV OPC diagnosis (LFRS p = 0.03; DFS p = 0.02) predicted outcomes on multivariate analysis. None of the pre-treatment ADC values were predictive of 2 year DFS in the HPV OPC subgroup (p = 0.21–0.68). Amongst participants without 2 year disease-free survival, HPV-OPC was found to have much lower primary tumour ADC_mean values than other HNSCC.

Conclusion:

Knowledge of HPV OPC status is required in order to determine the impact of the pre-treatment ADC values on post-CRT outcomes in HNSCC.

Advances in knowledge:

Pre-treatment ADC_mean and ADC_min values acquired using different ROI methods are not predictive of 2 year survival outcomes in HPV OPC.

Apparent diffusion coefficient agreement and reliability using different region of interest methods for the evaluation of head and neck cancer post chemo-radiotherapy

Objectives:

Post chemoradiotherapy (CRT) interval changes in apparent diffusion coefficient (ADC) have prognostic value in head and neck squamous cell cancer (HNSCC). The impact of using different region of interest (ROI) methods on interobserver agreement and their ability to reliably detect the changes in the ADC values was assessed.

Methods:

Following ethical approval, 25 patients (mean age 59.5 years, 21 male) with stage 3–4 HNSCC undergoing CRT were recruited for this prospective cohort study. Diffusion weighted MRI (DW-MRI) was performed pre-treatment and at 6 and 12 weeks following CRT. Two radiologists independently delineated ROIs using whole volume (ROI_v), largest area (ROI_a) or representative area (ROI_r) methods at primary tumour (n = 22) and largest nodal (n = 24) locations and recorded the ADC_mean. When no clear focus of increased DWI signal was evident at follow-up, a standardised ROI was placed (non-measurable or NM). Bland-Altman plots and interclass correlation coefficient (ICC) were assessed. Paired t-tests evaluated interval changes in pre- and post-treatment ADC_mean at each location, which were compared to the smallest detectable difference (SDD).

Results:

Excellent agreement was obtained for all ROI methods at pre-treatment (ICC 0.94–0.98) and 6-week post-treatment (ICC 0.94–0.98). At 12-week post-treatment, agreement was excellent (ICC 0.91–0.94) apart from ROI_r (ICC 0.86) and the NM nodal disease (ICC 0.87). There were significant interval increases in ADC_mean between pre-treatment and post-treatment studies, which were greater than the SDD for all ROIs.

Conclusions:

ADC_mean values can be reproducibly obtained in HNSCC using the different ROI techniques on pre- and post-CRT MRI, and this reliably detects the interval changes.

Surgical management of cerebellopontine angle epidermoid cysts: an institutional experience of 10 years

BACKGROUND

Cerebellopontine angle (CPA) epidermoids, although of benign nature, are of considerable neurosurgical interest because of their close proximity and adherence to the cranial nerves and brain stem. In this paper, we describe our experience and attempt to correlate the final outcomes with the extent of surgical removal. The main objectives were to study various modes of surgical management of CPA epidermoids with regard to removal and preservation of the cranial nerves and also to evaluate the role of endoscopic assisted microsurgical excision thereby minimizing recurrences. This case series is one of the largest series reported so far worldwide.

MATERIALS AND METHODS

From 2006 to 2016, 139 patients with CPA epidermoids were operated at Grant Medical College and J. J. Hospital, Mumbai. All patients underwent detailed magnetic resonance imaging (MRI) of brain. Lesions were classified according Rogelio Revuelta-Gutiérrez et al. with respect to their anatomic extent: grade I- within the boundaries of the CPA, grade II- extension to the suprasellar and perimesencephalic cisterns, and grade III-parasellar and temporomesial region involvement. Retrosigmoidal and sub temporal approaches were taken to excise the lesions. Endoscopic assisted microsurgical excision was done in cases with extensions beyond the CPA. Patient follow-up was based on outpatient repeated brain MRI studies.

RESULTS

The mean duration of symptoms before surgery was 42 months (range, 2 months to 6 years). The mean follow-up period was 27 months (range, 2-60 months). The main presenting sympt om was headache in 69% (96/139) of the cases and trigeminal neuralgia in 30% cases was the second most common cause of consultation. Seventy-five percent of patients had some degree of cranial nerve (CN) involvement. Retrosigmoid approach was taken in 92% patients and 7 patients with supratentorial extension were operated by combined retrosigmoidal and subtemporal approach. Endoscopic assisted microsurgical excision was done in 40% cases. Use of angled views by an endoscope helped to excise residual tumor in 47 (83%) patients. Complete excision was achieved in 67% of cases. In 33% patients, small capsular remnants could not be removed completely because of their adherence to vessels, brainstem and cranial nerves. Compared with their preoperative clinical status, 74% improved and 20% had persistent cranial nerve deficits in the first year of follow up.

CONCLUSIONS

Epidermoid cysts are challenging entities in current neurosurgery practice due to tumor adhesions to neurovascular structures. Meticulous surgical technique with the aid of neurophysiological monitoring is crucial to achieve safe and effective total or subtotal removal of these lesions. A conservative approach is indicated for patients in whom the fragments of capsule is adhered closely to blood vessels, nerves, or the brainstem, in order to avoid risk of serious neurological deficits related to an inadvertent damage of these structures. Use of angled views by endoscope at the conclusion of the surgery may assure the surgeon of total removal of the tumor.

Radiomic analysis for response assessment in advanced head and neck cancers, a distant dream or an inevitable reality? A systematic review of the current level of evidence

OBJECTIVE

The recent increase in publications on radiomic analysis as means to produce diagnostic and predictive biomarkers in head and neck cancers (HNCC) reveal complicated and often conflicting results. The objective of this paper is to systematically review the published data, and evaluate the current level of evidence accumulated that would determine clinical application.

METHODS

Data sources: Articles in the English language available on the Ovid-MEDLINE and Embase databases were used for the literature search. Study selection:Studies which evaluated the role of radiomics as a predictive or prognostic tool for response assessment in HNCC were included in this review.Study appraisal and synthesis methods: The authors set-out to perform a meta-analysis, however given the small number of studies retrieved that presented adequate data, combined with excessive methodological heterogeneity, we could only perform a structured descriptive systematic review summarizing the key findings. Independent extraction of articles was performed by two authors using predefined data fields and any disagreement was resolved by consensus.

RESULTS

Though most papers concluded that radiomics is an effective predictive and prognostic biomarker in the management of HNCC, significant heterogeneity exists in the study methodology and statistical modelling; thus precluding accurate mathematical comparison or the ability to make clear recommendations going forwards. Moreover, most studies have not been validated and the reproducibility of their results will be a challenge.

CONCLUSION

Until robust external validation studies on the reproducibility and accuracy of radiomic analysis methods on HNCC are carried out, the current level of evidence remains low, with the authors advising caution against hasty implementation of these tools in the multidisciplinary clinic.

ADVANCES IN KNOWLEDGE

This review is the first attempt to critically analyze the merits and demerits of currently published literature on tumour heterogeneity studies in HNCC, and identifies specific loop holes that need to be addressed by research groups, for a meaningful clinical translation of this potential biomarker.

P5570Contemporary trends and outcomes of percutaneous and surgical mitral valve replacement or repair for mitral insufficiency in cancer patients

Importance

Severe mitral valve insufficiency (MR) is managed using mitral valve replacement or repair. Transcatheter mitral valve repair (TMVR) is an emerging non-invasive treatment option for MR. Cancer patients stand to benefit from non-invasive treatment of MR given the nature of this intervention. Objective:We sought to assess the relative utilization, outcomes, and dispositions associated with TMVR vs. surgical mitral valve procedures (SMVP) in cancer patients.

Methods

The 2012–2015 National Inpatient Sample, a retrospective observational study was queried using ICD-9 codes for adults >18 years with comorbid MR (ICD-9 – 424.0) and cancer without metastatic disease. To maintain a homogenous study population and to limit confounding, those with mitral stenosis, rheumatic disease, infective endocarditis, aortic valve disease, or those undergoing any other vascular or cardiac surgery in the same admission were excluded from the analysis. Multiple in-hospital and disposition outcomes were evaluated. Since the baseline population undergoing SMVP (ICD-9: 35.23, 35.24, 35.12) is quite different from TMVR (ICD-9: 35.97), parallel analyses for outcomes and dispositions were presented but no direct statistical comparisons.

Results

A total of 410,175 out of 2,449,010 patients with mitral insufficiency were found to have non-metastatic cancer (16.7%). A total of 3,600 TMVR procedures were performed during the study period. Over the study period, there has been an increase in the proportion of patients undergoing TMVR among all patients undergoing mitral valve procedures (figure). The increase is higher in cancer patients in the most recent year (14.2% vs. 8.2%, p<0.0001). The four major cancers comprise of 50% of these TMVR patients. TMVR was associated with 1.4% vs. 2.2% in-hospital mortality (p=0.55), 0.7% vs. 0.8% stroke (p=0.87), 9.2% vs. 11.8% major bleeding (p=0.31), 14.1% vs. 16.5% acute kidney injury (p=0.52), 62.0% vs. 64.6% home discharge (p=0.58), and 13.3% vs. 12.0% discharge to nursing home (p=0.58) among cancer vs. non-cancer patients, respectively. On the other hand, SMVP was associated with 3.1% vs. 3.5% in-hospital mortality (p=0.35), 2.6% vs. 3.1% stroke (p=0.16), 35.0% vs. 30.5% major bleeding (p<0.0001), 19.5% vs. 19.6% acute kidney injury (p=0.88), 32.8% vs. 38.6% home discharge (p<0.0001), 37.2% vs. 35.0% home health care use (p<0.0001), and 26.8 vs. 22.8% discharge to nursing home (p=0.05), among cancer vs. non-cancer patients respectively.

TMVR percent in mitral valve procedures

Conclusion

TMVR utilization for MR in cancer has steadily increased in both cancer and non-cancer patients, although it is proportionately higher among cancer patients in recent years. Overall, TMVR was associated with low in-hospital mortality and a similar safety profile in cancer and non-cancer patients, while SMVP appears to have a slightly worse safety profile in cancer patients. Our findings, suggest that TMVR is a reasonable strategy in selective cancer patients with MR.

P2271Contemporary trends and outcomes of percutaneous vs. surgical aortic valve replacement in cancer patients

Importance

Cancer patients with severe AS are often ineligible for surgical aortic valve replacement (SAVR). Transcatheter aortic valve replacement (TAVR) is an emerging non-invasive treatment option for severe AS. Cancer patients likely stand to benefit from TAVR given its non-invasive nature; however, there is a paucity of data regarding the comparative effectiveness of TAVR vs. SAVR in cancer. We sought to assess the relative utilization, outcomes, and dispositions associated with TAVR vs. SAVR in cancer and non-cancer patients.

Methods

The US-based National Inpatient Sample was queried between 2012 and 2015 using ICD-9 codes for adults>18 years with comorbid AS and cancer without metastatic disease. Multiple in-hospital and disposition outcomes were evaluated. Comparison of TAVR vs SAVR required propensity score estimation using demographic, socio-economic, comorbidity, and hospital specific variables. A standardized morbidity ratio (SMR) weight was calculated by assigning TAVR a weight of 1, and those undergoing SAVR weight of PS/(1-PS). SMR-weighted generalized logistic regression was conducted to estimate the average effect of TAVR compared with SAVR. Finally, the Cochran–Mantel–Haenszel (CMH) test for propensity-matched data was utilized to compare the effect modification of cancer on these outcomes.

Results

A total of 979,912 out of 5,611,173 patients with AS were found to have non-metastatic cancer (17.5%). Average Elixhauser's mortality score of patients undergoing TAVR and SAVR was 8.9 vs. 8.1 and 8.5 vs. 7.1 for cancer vs. non-cancer respectively (p<0.0001). Over time, patients undergoing AVR increased in both groups, primarily driven by significantly increased rates of TAVR utilization in the cancer group. Over the study time period, an increase in the proportion of patients undergoing TAVR among all patients undergoing AVR was noted (figure) with 21.8% and 19.6% patient with prostate and breast cancer in 2015. TAVR in cancer patients was associated with lower odds of acute kidney injury [AKI; odds ratio (OR): 0.6, 95% confidence interval (CI): 0.5- 0.8], cardiogenic shock [OR: 0.6 (0.4–0.8)] and major bleeding [OR: 0.4 (0.3–0.5)] with no difference in in-hospital mortality and stroke compared to SAVR. Additionally, TAVR was associated with higher odds of home-discharge [OR: 1.9 (1.7–2.2)], and lower need for nursing facility transfer [OR: 0.7 (0.6–0.8) compared to SAVR among cancer patients. Similar outcomes are noted in the non-cancer cohort upon comparing TAVR to SAVR. However, favorable effect-modification of cancer was noted in regard to AKI (p=0.003), home discharge (p<0.0001), and less nursing facility transfer (p=0.0003), suggesting safety.

Conclusions

Compared to patients without cancer, the utilization of AVR in cancer patients has steadily increased. The benefits of TAVR over SAVR appear to extend to patients, regardless of cancer status. TAVR might be a more suitable procedure for cancer patients with AS.

Large Intradiploic Growing Skull Fracture of the Posterior Fossa with Syringomyelia

Growing skull fracture (GSF), also known as leptomeningeal cyst, is a rare but significant complication of pediatric head injury. It is mainly seen in infancy and childhood. GSFs of the posterior fossa are uncommon, and intradiploic location in the posterior fossa is extremely rare. Only a few cases of pediatric GSF of the posterior fossa and intradiploic location have been reported in the literature. We report a case of a 15-year-old boy who had large intradiploic GSF of the posterior fossa, associated with cervical syringomyelia. The lesion developed progressively over a period of 5 years following a documented occipital linear fracture. This case of a GSF developing from a known occipital linear fracture demonstrates that a GSF may reach a considerable size, and although uncommon, intradiploic development and occipital localization of a GSF are possible. Syringomyelia associated with posterior fossa GSF is very unusual which makes this case even more unique.

Management Strategies of Cranial Encephaloceles: A Neurosurgical Challenge

Background:

Encephalocele is defined as herniation of cranial contents beyond the normal confines of the skull through a defect in the calvarium either along the midline or at the base of skull. These anomalies should be repaired in the first few months of life to prevent neurological deficits and facial disfigurement. The aim of the surgery is water tight dural closure at the level of internal defect, closure of skull defect, and reconstruction of external bony deformity.

Materials and Methods:

Fifty-four cases of encephalocoeles were studied in our hospital over a 6-year period from 2010 to 2016. Computed tomography (CT) and magnetic resonance imaging (MRI) brain were performed to delineate the bony defect and associated anomalies. Reconstruction of the bony defect was done using autologous calvarial bone graft, Osteopore polycaprolactone (PCL) bone scaffold filler and titanium mesh.

Results:

In our study, 54 patients (34 boys and 20 girls) whose age varied between 2 months and 14 years were evaluated. Frontoethmoidal (44.5%) and occipital encephaloceles (25.9%) were the most frequently seen varieties. Repair of the dural defect either primarily or using pericranium was done in all cases. Closure of the bony defect was done using autologous calvarial bone graft in 12 (22.22%) patients. Titanium mesh was used in eight and Osteopore PCL bone scaffold filler in four children. Cranioplasty was not done in remaining thirty children because of the small bone defect. Overall, 80% had no postoperative problem and were discharged between 7 and 10 days of surgery. Cerebrospinal fluid leak was the most frequent postoperative complication, noted in five patients. Re-exploration with repair was done in one and remaining four were managed conservatively. Overall, cosmetic results were acceptably good, with parents judging the cosmetic outcome as good to excellent in 70%, satisfactory in 18%, and poor in 3% at the last follow-up.

Conclusion:

Our study demonstrated that encephaloceles are associated with complex deformities and pose a technical challenge to the neurosurgeon. A multidisciplinary approach is necessary to manage these cases. MRI brain and three dimensional CT aids in evaluating the deformity better and surgical correction should be performed as soon as possible to prevent a further neurological deficit. Repair of dural defect and reconstruction of the skull defect results in a good long-term outcome. We present our experience on 54 cases of cranial encephaloceles managed surgically over a period of only 6 years which is one of the largest series reported from Asia.

Unusual Case of Midline Middle Skull Base Lymphoma Mimicking as Invasive Pituitary Adenoma

Non-Hodgkin's lymphoma (NHL) is a rare tumor of the skull base. As the incidence of primary central nervous system (CNS) lymphoma has increased, atypical presentations involving the skull base are being reported. However, isolated involvement of middle skull base, that too predominantly the clivus and parasellar region, is rarely seen. We present a case of middle-age woman with midline skull base lesion located in the sella with invasion of the ventral part of upper part of clivus (posterior clinoid) and also the parasellar region causing involvement of optic and abducens nerve with preserved hormonal functions. She was operated endoscopically for partial resection of the lesion. Histopathology turned out to be non-Hodgkin's lymphoma of NK/T-cell variety. So far NK/T-cell lymphoma of the sella with invasion into the clivus has never been reported in literature to the best of our knowledge.