CT-derived radiomics predict the growth rate of renal tumours in von Hippel-Lindau syndrome

AIM

To predict renal tumour growth patterns in von Hippel-Lindau syndrome by utilising radiomic features to assist in developing personalised surveillance plans leading to better patient outcomes.

MATERIALS AND METHODS

The study evaluated 78 renal tumours in 55 patients with histopathologically-confirmed clear cell renal cell carcinomas (ccRCCs), which were segmented and radiomics were extracted. Volumetric doubling time (VDT) classified the tumours into fast-growing (VDT <365 days) or slow-growing (VDT ≥365 days). Volumetric and diametric growth analyses were compared between the groups. Multiple logistic regression and random forest classifiers were used to select the best features and models based on their correlation and predictability of VDT.

RESULTS

Fifty-five patients (mean age 42.2 ± 12.2 years, 27 men) with a mean time difference of 3.8 ± 2 years between the baseline and preoperative scans were studied. Twenty-five tumours were fast-growing (low VDT, i.e., <365 days), and 53 tumours were slow-growing (high VDT, i.e., ≥365 days). The median volumetric and diametric growth rates were 1.71 cm3/year and 0.31 cm/year. The best feature using univariate analysis was wavelet-HLL_glcm_ldmn (area under the receiver operating characteristic [ROC] curve [AUC] of 0.80, p<0.0001), and with the random forest classifier, it was log-sigma-0-5-mm-3D_glszm_ZonePercentage (AUC: 79). The AUC of the ROC curves using multiple logistic regression was 0.74, and with the random forest classifier was 0.73.

CONCLUSION

Radiomic features correlated with VDT and were able to predict the growth pattern of renal tumours in patients with VHL syndrome.

Very-high-risk localized prostate cancer: definition and outcomes

BACKGROUND

Outcomes in men with National Comprehensive Cancer Network (NCCN) high-risk prostate cancer (PCa) can vary substantially-some will have excellent cancer-specific survival, whereas others will experience early metastasis even after aggressive local treatments. Current nomograms, which yield continuous risk probabilities, do not separate high-risk PCa into distinct sub-strata. Here, we derive a binary definition of very-high-risk (VHR) localized PCa to aid in risk stratification at diagnosis and selection of therapy.

METHODS

We queried the Johns Hopkins radical prostatectomy database to identify 753 men with NCCN high-risk localized PCa (Gleason sum 8-10, PSA >20 ng ml(-1), or clinical stage ≥T3). Twenty-eight alternate permutations of adverse grade, stage and cancer volume were compared by their hazard ratios for metastasis and cancer-specific mortality. VHR criteria with top-ranking hazard ratios were further evaluated by multivariable analyses and inclusion of a clinically meaningful proportion of the high-risk cohort.

RESULTS

The VHR cohort was best defined by primary pattern 5 present on biopsy, or ≥5 cores with Gleason sum 8-10, or multiple NCCN high-risk features. These criteria encompassed 15.1% of the NCCN high-risk cohort. Compared with other high-risk men, VHR men were at significantly higher risk for metastasis (hazard ratio 2.75) and cancer-specific mortality (hazard ratio 3.44) (P<0.001 for both). Among high-risk men, VHR men also had significantly worse 10-year metastasis-free survival (37% vs 78%) and cancer-specific survival (62% vs 90%).

CONCLUSIONS

Men who meet VHR criteria form a subgroup within the current NCCN high-risk classification who have particularly poor oncological outcomes. Use of these characteristics to distinguish VHR localized PCa may help in counseling and selection optimal candidates for multimodal treatments or clinical trials.

Fatal neutropenia and thrombocytopenia associated with ticlopidine after stenting

We report 3 cases of fatal neutropenia and thrombocytopenia associated with ticlopidine after coronary stenting. Patients should be counseled about the early signs of infection and bleeding and to have regularly scheduled complete blood counts.

Assessment of the results of percutaneous transluminal coronary angioplasty using an integrated ultrasound imaging-angioplasty catheter

To evaluate the results percutaneous transluminal coronary angioplasty (PTCA), intravascular ultrasound imaging was performed in 32 proximal coronary arterial segments and in 16 atherosclerotic lesions after PTCA in 13 patients using a 5 Fr balloon catheter with an ultrasound transducer mounted just proximal to the balloon. Simultaneous angiographic measurements of vessel diameter were also performed using electronic calipers from contrast cine angiograms. There was good correlation between ultrasound and angiographic minimum luminal diameters of the normal proximal vessel (y = 0.59x + 1.49, r = 0.70, P < 0.01, n = 32). However, the luminal diameter measured by intravascular ultrasound was significantly greater than when measured by contrast angiography (2.81 +/- 0.10 vs. 2.34 +/- 0.12mm, n = 16, P < 0.001, mean +/- SEM). Post-PTCA, there was good correlation between ultrasound and angiographic minimum luminal diameters of the lesion (y = 0.62x + 1.42, r = 0.76, P < 0.001, n = 16), but again luminal diameters were significantly greater when measured by intravascular ultrasound compared to contrast angiography (2.61 +/- 0.08 vs. 1.89 +/- 0.10mm, n = 16, P < 0.001). Furthermore, residual stenosis was significantly less when determined by intravascular ultrasound than by contrast angiography (7.3 +/- 2.0 vs. 18.1 +/- 2.1%, n = 16, P < 0.001). Intravascular ultrasound was able to detect coronary calcification that was not evident by contrast coronary angiography in 8 of 16 lesions. Post-PTCA, dissection was evident in four lesions by ultrasound, whereas dissection was appreciated in only three lesions by contrast angiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Radiation exposure: comparison of rapid exchange and conventional over-the-wire coronary angioplasty systems

The growth of coronary angioplasty has resulted in increased fluoroscopy time to patients, staff, and physicians. Rapid exchange-type catheters have purported to reduce fluoroscopy time and procedure time compared to conventional over-the-wire systems. Of 150 consecutive patients, 54 were treated solely with rapid-exchange catheters and 84 were treated solely with over-the-wire catheters. Excluding 12 cases treated with fixed wire or combination catheters, the following data were found: [table: see text] Overall procedural success was obtained in 98.5% (136/138) of patients, 1.5% (2) requiring emergency coronary artery bypass graft surgery. A significant 35% reduction in fluoroscopy time and 13% reduction in procedure time were found when rapid-exchange catheters were used, with identical success rates, number of balloons used per case, and complication rates compared to over-the-wire catheters. Rapid-exchange catheters should be considered as part of an overall effort to reduce radiation exposure in the interventional cardiology laboratory.

Successful excimer laser angioplasty following unsuccessful primary balloon angioplasty

We report five patients where excimer laser coronary angioplasty facilitated successful balloon dilatation of heavily calcified lesions that could not be dilated by conventional angioplasty techniques alone. In each case, the lesion was crossed successfully with a guide wire. Conventional angioplasty failed because of inability to cross the lesion with a balloon (four lesions) or inability to dilate the lesion with balloon inflation (two lesions). These cases illustrate an indication for excimer laser coronary angioplasty as an adjunctive procedure in heavily calcified coronary stenoses.

Percutaneous laser-assisted thermal coronary angioplasty in native coronary arteries and saphenous vein grafts: initial results and angiographic follow-up

Percutaneous laser-assisted thermal coronary angioplasty was attempted in 29 vessels (27 patients): 10 left anterior descending, 2 left circumflex and 17 mid-shaft (non-anastomotic) saphenous vein grafts. Argon or YAG laser thermal energy was applied via a 1.3, 1.6 or 1.9 mm metal capped probe followed by conventional balloon angioplasty in 27 vessels and sole thermal laser therapy in two vessels. The laser probe successfully crossed 83% (24/29) of vessels and subsequent balloon dilatation increased the success rate to 93% (25/27). Perforation occurred in a vein graft resulting in one in-hospital death post repeat emergency coronary artery bypass graft surgery. Angiographic follow-up was obtained in 85% (24/28) of vessels. Angiographic restenosis ( greater than 50% reduction in lumen diameter) occurred in 27% (3/11) of native coronary arteries and 62% (8/13) of saphenous vein grafts. Therefore, despite high initial success rates, the application of laser thermal energy with small laser probes relative to vessel size, followed by conventional balloon angioplasty, does not appear to alter restenosis. Further evaluation of coronary laser systems should be continued only with catheters that are capable of creating channels closer to the size of the vessel treated.

Percutaneous transluminal coronary angioplasty for acute myocardial infarction

Studies have suggested that intracoronary and intravenous thrombolysis and emergency PTCA result in decreased infarct size, improved left ventricular function, and decreased in-hospital mortality. Significant problems remain with all three treatment modalities. Thrombolysis is associated with significant bleeding, especially if acute catheterization also is performed. The intracoronary method of thrombolysis requires cardiac catheterization facilities and entails a significant delay in reperfusion. Lower rates of reperfusion initially were found with intravenous than intracoronary streptokinase, but the intravenous administration of t-PA has been associated with a reperfusion rate (75 per cent) similar to that of intracoronary streptokinase. Significant bleeding complications occur with t-PA just as with streptokinase. Furthermore, there are patients in whom thrombolysis is contraindicated because of the high risk of life-threatening hemorrhagic complications. Once thrombolysis is achieved, an underlying significant coronary artery lesion usually is present so that a significant risk of recurrent ischemia and/or reinfarction still exists. In controlled studies, the addition of cardiac catheterization and angioplasty after thrombolytic therapy is associated with a further increase in significant bleeding episodes. Also, in low-risk subgroups of patients randomized to emergency angioplasty versus elective angioplasty or noninvasive treatment after thrombolytic therapy, the complications of angioplasty may outweigh the benefits of further reduction in lesion severity. Potential problems of emergency angioplasty following thrombolytic therapy include: (1) hemorrhage into ischemic myocardium, which may have a deleterious effect on ultimate muscle recovery; (2) hemorrhage at the angioplasty site caused by thrombolytic therapy, with a resultant increased chance of occlusion of the vessel post-angioplasty, and (3) production of reperfusion arrhythmias and hypotension, predisposing to vessel reclosure and infarct extension. With primary angioplasty therapy, the reperfusion success rate is 85 to 90 per cent. This is higher than the approximately 75 per cent success rate with thrombolytic therapy alone. If angioplasty can be performed expeditiously, within 6 hours of the onset of ischemia, potential advantages of this technique include: (1) rapid reperfusion, possibly comparable to thrombolytic therapy alone; (2) higher success rate for reperfusion than thrombolytic therapy; (3) alleviation of underlying stenosis usually present after thrombolytic therapy alone; (4) avoidance of systemic thrombolysis, with a concomitant decrease in hemorrhagic risk; (5) possible avoidance of hemorrhagic infarction, which may have a deleterious effect on ultimate muscle recovery; and (6) applicability to patients in cardiogenic shock, who presently respond poorly to thrombolytic therapy alone. No large controlled randomized study exists comparing primary angioplasty with thr