Prognostic value of deep learning-derived body composition in advanced pancreatic cancer-a retrospective multicenter study

BACKGROUND

Despite the prognostic relevance of cachexia in pancreatic cancer, individual body composition has not been routinely integrated into treatment planning. In this multicenter study, we investigated the prognostic value of sarcopenia and myosteatosis automatically extracted from routine computed tomography (CT) scans of patients with advanced pancreatic ductal adenocarcinoma (PDAC).

PATIENTS AND METHODS

We retrospectively analyzed clinical imaging data of 601 patients from three German cancer centers. We applied a deep learning approach to assess sarcopenia by the abdominal muscle-to-bone ratio (MBR) and myosteatosis by the ratio of abdominal inter- and intramuscular fat to muscle volume. In the pooled cohort, univariable and multivariable analyses were carried out to analyze the association between body composition markers and overall survival (OS). We analyzed the relationship between body composition markers and laboratory values during the first year of therapy in a subgroup using linear regression analysis adjusted for age, sex, and American Joint Committee on Cancer (AJCC) stage.

RESULTS

Deep learning-derived MBR [hazard ratio (HR) 0.60, 95% confidence interval (CI) 0.47-0.77, P < 0.005] and myosteatosis (HR 3.73, 95% CI 1.66-8.39, P < 0.005) were significantly associated with OS in univariable analysis. In multivariable analysis, MBR (P = 0.019) and myosteatosis (P = 0.02) were associated with OS independent of age, sex, and AJCC stage. In a subgroup, MBR and myosteatosis were associated with albumin and C-reactive protein levels after initiation of therapy. Additionally, MBR was also associated with hemoglobin and total protein levels.

CONCLUSIONS

Our work demonstrates that deep learning can be applied across cancer centers to automatically assess sarcopenia and myosteatosis from routine CT scans. We highlight the prognostic role of our proposed markers and show a strong relationship with protein levels, inflammation, and anemia. In clinical practice, automated body composition analysis holds the potential to further personalize cancer treatment.

Association of QRS-T angle and Late Gadolinium Enhancement in patients with a Clinical Suspicion of Myocarditis

Objective: To investigate the association of a wide QRS-T angle on the surface ECG and late gadolinium enhancement on contrast-enhanced cardiovascular magnetic (CMR) imaging in patients with clinically suspected myocarditis. Background: Diagnosis and risk stratification in patients with suspected myocarditis is particularly challenging due to a great spectrum of clinical presentations. Late gadolinium enhancement (LGE) visualizes myocardial necrosis and fibrosis in patients with biopsy-proven myocarditis. The presence or absence of late gadolinium enhancements in these patients is prognostically meaningful. The QRS-T angle from the surface ECG, on the other hand, may serve as a simple and easily available risk marker in suspected myocarditis. Methods: We enrolled 97 consecutive patients that were referred to CMR imaging for a clinical suspicion of myocarditis. All patients obtained a standardized digital 12-lead ECG for the calculation of the QRS-T angle and underwent contrast-enhanced CMR imaging. Patients were divided into two groups according to the absence or presence of LGE on CMR. Results: 78 of 97 patients with suspected myocarditis had LGE on CMR. Patients with LGE had wider QRS-T angles as compared to the patient group without LGE (53.95-47.5 vs. 26.2-21.2; p<0.001). The sensivity, specificity, negative predictive value and positive predictive value for a QRS-T angle above 90 degrees for LGE positive myocarditis were 16.5%, 100%, 24.7%, and 100%, respectively. Conclusion: A wide QRS-T angle of 90 degrees or more is linked to myocardial fibrosis or necrosis (late gadolinium enhancement) in patients with suspected myocarditis.

QRS-T-angle in Patients with ST-Segment Elevation Myocardial Infarction (STEMI) - a Comparison with Cardiac Magnetic Resonance Imaging

Background: The QRS-T angle from the surface EKG is a promising prognostic marker in patients with coronary artery disease. Cardiovascular magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE) offers high resolution imaging of myocardial damage. We investigated the association of the QRS-T angle and the extent of myocardial damage as assessed by LGE in patients with acute ST-segment myocardial infarction (STEMI) Methods: 169 patients with STEMI obtained a standardized digital 12-lead EKG on admission for the calculation of the QRS-T angle and underwent CMR imaging for analysis of infarct size by LGE within the first week. Patients were divided into groups: (1) abnormal QRS-T angle ≥ 90 degree and (2) QRS-T angle < 90 degree. Results: Patients with a QRS-T angle of 90 degree or more had larger infarcts (36.5±12.4 vs. 13.3±9.5; p<0.001) and lower ejection fraction (42.9±12.1% vs. 50.6±10.6%; p<0.001). Conclusion: The extent of myocardial damage as measured by the gold standard LGE is associated with a larger QRS-T angle calculated from the surface EKG.

Evaluation of a low-carbohydrate diet-based preparation protocol without fasting for cardiac PET/MR imaging

OBJECTIVE

Assessment of increased glucose uptake in inflammatory or malignant myocardial disease using PET/MRI relies on uptake suppression in normal myocardium. We evaluated the efficacy of a ≥24 hours high-fat, low-carbohydrate, and protein-permitted diet (HFLCPP) in combination with unfractionated heparin for suppression of "physiologic" myocardial glucose uptake.

METHODS

PET/MRI was successfully performed in 89 patients. HFLCPP was started ≥24 hours prior to PET/MRI. All patients received i.v. injection of unfractionated heparin (50 IU·kg-1) 15 minutes prior to FDG administration. Left ventricular FDG uptake was visually evaluated by two readers. Diffuse myocardial uptake exceeding liver uptake, isolated uptake in the lateral wall, or diffuse uptake in the entire circumference of the heart base were defined as failed suppression. Homogeneous myocardial uptake below liver uptake with/without focal uptake was defined as successful suppression.

RESULTS

Success rate was 84%. Suppression was unsuccessful in 14 patients. No significant influence of gender (P = .40) or age (P = .21) was found. However, insufficient suppression was more common in patients younger than 45 years (20% vs 7%). PET/MR imaging completion rate was >97%.

CONCLUSION

A HFLCPP diet in combination with unfractionated heparin was successfully implemented for cardiac PET/MRI and resulted in a sufficient suppression of myocardial FDG uptake in 84% of patients.

[Extensive left ventricular myocardial fat deposition detected by cardiac MRI]

Although it is well known from pathological studies that intramyocardial fat deposition frequently occurs after left ventricular myocardial infarction, a left ventricular fat deposition is rarely diagnosed in the clinical routine. We report the case of extensive fat deposition in the left ventricular myocardium which was detected by routine cardiac magnetic resonance imaging.

Cardiac MRI: estimation of changes in normalized myocardial gadolinium accumulation over time after contrast injection in patients with acute myocarditis and healthy volunteers

PURPOSE

An increased normalized gadolinium accumulation (NGA) in the myocardium during early washout has been used for the diagnosis of acute myocarditis (AM). Due to the fact that the pharmacokinetics of contrast agents are complex, time-related changes in NGA after contrast injection are likely. Because knowledge about time-related changes of NGA may improve the diagnostic accuracy of MR, our study aimed to estimate the time course of NGA after contrast injection in patients as well as in healthy volunteers.

MATERIALS AND METHODS

An ECG-triggered inversion recovery SSFP sequence with incrementally increasing inversion times was repetitively acquired over the 15 minutes after injection of 0.2 Gd-DTPA per kg body weight in a 4-chamber view in 15 patients with AM and 20 volunteers. The T 1relaxation times and the longitudinal relaxation rates (R1) of the myocardium and skeletal musculature were calculated for each point in time after contrast injection. The time course of NGA was estimated based on the linear relationship between R1 and tissue Gd concentration.

RESULTS

NGA decreased over time in the form of a negative power function in patients with AM and in healthy controls. NGA in AM tended to be higher than in controls (p > 0.05).

CONCLUSION

NGA rapidly changes after contrast injection, which must be considered when measuring NGA. Although we observed a trend towards higher NGA values in patients with AM with a maximum difference one minute after contrast injection, NGA did not allow us to differentiate patients with AM from healthy volunteers, because the observed differences did not reach a level of significance.

Magnetic resonance coronary angiography: comparison between a Gd-BOPTA- and a Gd-DTPA-enhanced spoiled gradient-echo sequence and a non-contrast-enhanced steady-state free-precession sequence

BACKGROUND

Several studies have demonstrated that the administration of contrast agents is advantageous in magnetic resonance coronary angiography (MRCA).

PURPOSE

To compare a non-contrast-enhanced steady-state free-precession (SSFP) with a contrast-enhanced inversion recovery spoiled gradient-echo (IR-GE) sequence using two different contrast agents for MRCA.

MATERIAL AND METHODS

Eight healthy volunteers were examined on a 1.5T MR scanner. For non-contrast-enhanced MRCA, a breath-hold three-dimensional (3D) SSFP sequence (repetition/echo time [TR/TE] 3.9/1.7 ms, flip angle [FA] 65 degrees) was used. Contrast-enhanced MRCA was performed repetitively in two imaging sessions over 30 min after injection of 0.2 mmol/kg body weight gadobenate dimeglumine (Gd-BOPTA) or gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) using a breath-hold 3D IR-GE sequence (TR/TE 4.1/1.7 ms, FA 15 degrees). The signal-to-noise ratios (SNR) of the coronary arteries, as well as the contrast-to-noise ratios (CNR) between coronary arteries and perivascular tissue, were calculated for all images. Blood T (1) values were repetitively estimated over 30 min using an SSFP sequence with incrementally increasing inversion times (TR/TE 2.4/1.0 ms, FA 50 degrees).

RESULTS

Gd-BOPTA-enhanced images showed significantly (P<0.05) higher SNR and CNR compared to Gd-DTPA-enhanced images for all times after contrast injection (SNR: 1 min post injection [PI] 26.4+/-4.2 vs. 16.2+/-3.1; CNR: 1 min PI 21.4+/-3.7 vs. 13.2+/-2.6). Compared to the SSFP images, the Gd-BOPTA-enhanced images showed higher CNR values for all times after injection (1 min PI 21.4+/-3.7 vs. 13.8+/-5.5; P<0.05), whereas the Gd-DTPA-enhanced images did not (1 min PI 13.2+/-2.6 vs. 13.8+/-5.5; P>0.05). Blood T (1) estimates were not significantly different for either agent 1 min after administration (P>0.05), but they were significantly lower for Gd-BOPTA (P<0.05) from 7 to 25 min after injection.

CONCLUSION

Compared to non-contrast-enhanced SSFP images, only Gd-BOPTA-enhanced images show a significantly improved contrast between the coronary arteries and the surrounding tissue.

[Quantification of microvascular obstruction in acute myocardial infarction using cardiac MRI]

PURPOSE

Microvascular obstruction (MO) and the extent of infarction are important prognostic factors in acute myocardial infarction. Our study aimed to investigate the effect of the time interval between contrast administration and image acquisition on the quantification of microvascular obstruction and myocardial infarction.

MATERIALS AND METHODS

50 consecutive patients with acute myocardial infarction (40 male, mean age 58.1 +/- 11.7 years) treated by percutaneous coronary revascularization resulting in a grade 3 flow according to the thrombolysis in myocardial infarction flow classification were examined on a 1.5 T MR scanner within the first 5 days after infarction. 2, 5, 10, and 20 minutes after I.V. administration of 0.2 mmol/kg per kg body weight of Gadodiamid (Omniscan), GE Healthcare Buchler, Germany), a single shot IR-SSFP sequence (TR 2.4 ms, TE 1.08 ms, TI 180 - 280 ms, FA 50 degrees) covering the entire left ventricle was acquired. Areas of MO and myocardial infarction were measured for all times after contrast injection (p. i.).

RESULTS

MO was detected in 32 of 50 patients two minutes p. i., while 23 patients showed evidence of MO (p = 0.002) 20 min. p. i. In all patients with MO, the extent of MO decreased over time (7.4 +/- 9.0 % of the LV myocardium 2 min. p. i. vs. 2.4 +/- 4.6 % 20 min. p. i. p < 0.0001). The area of myocardial infarction increased from 13.9 +/- 13.5 % 2 min. p. i. to 18.6 +/- 14.2 % 10 min. p. i. (p < 0.0001), and then remained unchanged (18.7 +/- 14.3 % at 20 min. p = 0.57).

CONCLUSION

Our study shows that the time delay between contrast media injection and image acquisition has a significant impact on the delimitable extent of MO and infarct size.

Prevalence, pattern, and functional impact of late gadolinium enhancement in left ventricular hypertrophy due to aortic valve stenosis

PURPOSE

To assess the prevalence and pattern of myocardial late gadolinium enhancement (LGE) and its functional impact on patients with left ventricular hypertrophy caused by aortic valve stenosis.

MATERIALS AND METHODS

Cardiac magnetic resonance imaging of 40 patients (17 female, 23 male, mean age: 76.6 +/- 22.5 years) with known aortic valve stenosis (mean aortic valve area: 89.8 +/- 19.2 mm(2)) and without coronary artery disease was performed at 1.5 T using steady-state free precession sequences for aortic valve planimetry and for the assessment of left ventricular (LV) volumes and mass. Ten to 15 minutes after injection of 0.2 mmol Gd-DTPA per kilogram body weight, inversion-recovery prepared spoiled gradient echo images were acquired in standard long and short axis views to detect areas of LGE.

RESULTS

LGE was observed in 32.5 % (13/40) of our patients. LGE was mainly located in the basal septal and inferior LV segments, and showed a non-ischemic pattern with sparing of the subendocardial region. Patients with LGE showed lower LV ejection fractions (55.5 +/- 13.8 % vs. 69.1 +/- 10.7 %, p = 0.0014), higher LV end-systolic volumes (59.8 +/- 33.3 ml vs. 36.6 +/- 16.0 ml, p = 0.0048), and LV masses (211.0 +/- 13.8 vs. 157.9 +/- 37.5 g, p = 0.0002) compared to patients without LGE.

CONCLUSION

LGE is frequent in patients with hypertrophic left ventricles due to aortic valve stenosis and is associated with worse LV function.

Cervical lymph node metastases of unknown origin: primary tumor detection with whole-body positron emission tomography/computed tomography

BACKGROUND

Identification of primary tumor in patients with cervical lymph node metastasis of unknown primary (MUO) has a great impact on therapy approach and potentially on patient prognosis.

PURPOSE

To assess the diagnostic accuracy of combined positron emission tomography(PET)/computer tomography (CT) for primary tumor detection in cervical metastases of unknown origin compared to PET, CT, and PET+CT side-by-side evaluation.

MATERIAL AND METHODS

39 consecutive patients (eight women, 31 men; mean age 59.9 ± 11.2 years) with MUO were enrolled in this study. PET/CT images were obtained 1 hour after injection of 350 MBq of fluorodeoxyglucose. Oral and intravenous contrast agents were administered in all patients to ensure diagnostic CT data. Fused PET/CT data were evaluated for primary tumor detection. Diagnostic accuracy was calculated and compared with CT alone, PET alone, and side-by-side PET+CT evaluation.Statistical analysis of differences in diagnostic performance between the different imaging procedures was based on the McNemar test.

RESULTS

Fused PET/CT depicted the primary tumor in 11 of 39 (28%) patients. In 28(72%) patients, the primary tumor remained occult. CT revealed the primary in five(13%), PET alone in 10 (26%), and side-by-side evaluation of PET+CT in 10 (26%) of 39 patients. Statistical analysis showed no significant differences between the imaging modalities.

CONCLUSION

PET, side-by-side PET+CT, and PET/CT revealed similar detection rates for primary tumors in cervical MUO patients. Therefore, cervical metastases of an unknown primary may be assessed with either of these imaging modalities. Detection rates with CT were substantially lower. Thus, inclusion of functional data for assessment of cervical MUO patients must be recommended.

MR characterization of cardiac abnormalities in HIV+ individuals with increased BNP levels

OBJECTIVE

To characterize cardiac abnormalities in HIV+ patients with increased serum B-type natiuretic peptide (BNP) by contrast-enhanced cardiac magnetic resonance imaging (MRI).

DESIGN

Non-blinded prospective consecutive cohort evaluation.

METHODS

More than 400 HIV+ patients were screened for potential BNP alterations. 16 met the inclusion criteria of elevated BNP levels and 12 patients could finally be enrolled. MRI analysis comprised function, oedema and late enhancement sequences.

RESULTS

Patients exhibited a median serum BNP level of 249 pg/ml. Based on MRI, diagnosis of left ventricular hypertrophy (n = 3), myocarditis (n = 2), chronic myocardial infarction (n = 2), dilated cardiomyopathy (n=1) and right ventricular failure (n = 1) was made.

CONCLUSIONS

Although no specific MR pattern was found, MR allowed characterization of the underlying cardiac pathologies in 82% of HIV+ patients with elevated BNP levels.

MR-Koronarangiographie mit MS-325, einem Blood-Pool-Kontrastmittel: Vergleich einer Inversion Recovery Steady-State Free Precession und einer Inversion Recovery Fast Low Angle Shot Sequenz in Probanden

PURPOSE

To compare the signal-to-noise and contrast-to-noise ratio as well as the image quality of 3D inversion recovery steady-state free precession (IR-SSFP) and 3D inversion recovery fast low angle shot (IR-FLASH) sequences for contrast-enhanced breath-hold MRCA.

MATERIALS AND METHODS

24 healthy volunteers (10 female, 14 male, mean age 29.8 +/- 6.1 years) were involved in this study. All examinations were performed on a 1.5 T MR scanner (Magnetom Sonata, Siemens, Germany) after injection of 0.05 mmol/kg body weight MS-325 (EPIX Pharmaceuticals, Cambridge, MA and Schering AG, Berlin, Germany). MRCA was performed using IR-SSFP (TR 3.8 ms, TE 1.6 ms, FA 65 degrees , 35 phase encoded steps, bandwidth 540 Hz/pixel, slice thickness 1.5 mm, in-plane resolution 1.2 x 0.9 - 1.4 x 1.0 mm) and IR-FLASH (TR 3.8 ms, TE 1.6 ms, FA 25 degrees , bandwidth 490 Hz/pixel, slice thickness 1.5 mm, in-plane resolution 1.2 x 0.9 - 1.4 x 1.0 mm) sequences. For all scans the inversion time was set to null the signal intensity of the myocardium. Signal-to-noise ratio (SNR) as well as contrast-to-noise ratio (CNR) measurements (blood versus myocardium) were performed. The image quality was assessed based on a 5-point scale ranging from 1 (excellent) to 5 (non-diagnostic) by two radiologists in consensus.

RESULTS

The mean signal-to-noise ratio of blood (27.7 +/- 4.7 vs. 22.6 +/- 4.9, P < 0.0001) and the contrast-to-noise ratio (21.0 +/- 4.3 vs. 15.8 +/- 4.3, P < 0.0001) showed significantly higher values for IR-SSFP sequences. The mean image quality scores were significantly higher for SSFP (3.6 +/- 0.7) than FLASH (2.8 +/- 0.9) sequences (P < 0.05).

CONCLUSION

IR-SSFP sequences show a considerable overall improvement in image quality compared to IR-FLASH sequences for MRCA after injection of a gadolinium-based blood pool contrast agent.

[Effects of high-energy shock waves on the structure of the immature epiphysis--a histomorphological study]

AIM

Extracorporeal shock wave treatment of infantile skeleton diseases is theoretical reasonable. The aim of this study was to investigate if extracorporeal shock wave therapy (ESWT) may cause damage to the epiphysis within the energy range of human application doses.

METHOD

18 rabbits were treated with 800 extracorporeal shock waves (Philips lithotripter LDM-E, energy density 0.32 mJ/mm(2)) at the proximal tibia epiphysis. At 72 hours, 14 days and 4 weeks each after shock wave application 6 rabbits were sacrificed.

RESULTS

Histological examination showed no damage to the epiphysis in all treated subjects.

CONCLUSION

This experimental study demonstrates that, under the conditions used in human shock wave therapy, no damage to the rabbit epiphysis occurs.

Dilated cardiomyopathy in two adult human immunodeficiency positive (HIV+) patients possibly related to highly active antiretroviral therapy (HAART)

Human immunodeficiency virus (HIV) and acute immunodeficiency syndrome are known to be associated with cardiac involvement. In this respect, a relation between HIV and dilated cardiomyopathy has been described. Additionally, highly active antiretroviral therapy (HAART) may independently contribute to cardiac impairment. We here report two cases of severely reduced left ventricular function detected in the context of a recent standardized screening of 132 HIV+ individuals of the German heart failure network. Both patients presented in a poor overall condition and progressive exercise-induced dyspnea accompanied by edema or angina pectoris, respectively. Subsequent examinations revealed left bundle-branch blockade, ventricular arrhythmia, elevated serum BNP-levels as well as pathologic transthoracic echocardiography, left ventricular angiography, electron beam tomography and cardiac magnetic resonance imaging without significant coronary stenoses or immunohistological signs of an ongoing or prior myocarditis. Clinical signs of progressive chronic heart failure developed slowly but constantly following initiation of the HAART regimen. Patients were treated by an implantation of a biventricular implantable cardioverter defibrillator beside conventional conservative standard therapy followed by a significant improvement of clinical symptoms. Antiviral medication could be maintained in both patients. Taking all data into account, the diagnosis of a HAART-associated dilated cardiomyopathy could be assessed. Even though the pathogenesis of secondary heart failure after HAART is still object of investigation a mitochondrial impairment by antiviral drugs is thought to contribute the development of dilated cardiomyopathy. However, due to the coexistence of an eminent HIV infection, a direct effect of the HI virus itself can not be completely excluded.

Gallbladder metastasis of non-small cell lung cancer

BACKGROUND

Although non-small cell lung cancer is known for its potency to spread to almost any organ of the body, metastasis to the gallbladder with significant clinical manifestation is rarely reported in the literature.

CASE REPORT

We report the case of a 45-year-old man with non-small cell lung cancer (NSCLC), who developed symptoms of acute cholecystitis caused by a metastasis of the gallbladder wall. Histological examination showed tumor cell invasion in regional gallbladder lymph nodes. A second primary tumor of the gallbladder was excluded by immunohistochemical methods.

CONCLUSION

Our experience showed that acute cholecystitis can occur in association with metastases of lung cancer to the gallbladder.