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1.
Eur J Radiol ; 141: 109773, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34022475

ABSTRACT

PURPOSE: To assess whether CT-based radiomics of the ablation zone (AZ) can predict local tumour progression (LTP) after thermal ablation for colorectal liver metastases (CRLM). MATERIALS AND METHODS: Eighty-two patients with 127 CRLM were included. Radiomics features (with different filters) were extracted from the AZ and a 10 mm periablational rim (PAR)on portal-venous-phase CT up to 8 weeks after ablation. Multivariable stepwise Cox regression analyses were used to predict LTP based on clinical and radiomics features. Performance (concordance [c]-statistics) of the different models was compared and performance in an 'independent' dataset was approximated with bootstrapped leave-one-out-cross-validation (LOOCV). RESULTS: Thirty-three lesions (26 %) developed LTP. Median follow-up was 21 months (range 6-115). The combined model, a combination of clinical and radiomics features, included chemotherapy (HR 0.50, p = 0.024), cT-stage (HR 10.13, p = 0.016), lesion size (HR 1.11, p = <0.001), AZ_Skewness (HR 1.58, p = 0.016), AZ_Uniformity (HR 0.45, p = 0.002), PAR_Mean (HR 0.52, p = 0.008), PAR_Skewness (HR 1.67, p = 0.019) and PAR_Uniformity (HR 3.35, p < 0.001) as relevant predictors for LTP. The predictive performance of the combined model (after LOOCV) yielded a c-statistic of 0.78 (95 %CI 0.65-0.87), compared to the clinical or radiomics models only (c-statistic 0.74 (95 %CI 0.58-0.84) and 0.65 (95 %CI 0.52-0.83), respectively). CONCLUSION: Combining radiomics features with clinical features yielded a better performing prediction of LTP than radiomics only. CT-based radiomics of the AZ and PAR may have potential to aid in the prediction of LTP during follow-up in patients with CRLM.


Subject(s)
Catheter Ablation , Colorectal Neoplasms , Liver Neoplasms , Colorectal Neoplasms/diagnostic imaging , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Retrospective Studies , Tomography, X-Ray Computed
2.
Case Rep Surg ; 2021: 6676109, 2021.
Article in English | MEDLINE | ID: mdl-33880199

ABSTRACT

Surgical liver resection is a treatment option in patients with resectable colorectal liver metastases. We present two cases of focal nodular hyperplasia (FNH) development after treatment with oxaliplatin during follow-up of colon carcinoma. The first case was a 40-year-old male patient who developed multiple liver lesions suspect for metastatic disease four years after he had undergone laparoscopic right-sided hemicolectomy and adjuvant chemotherapy (capecitabine and oxaliplatin). He underwent a metastasectomy of segments three and four and microwave ablation (MWA) of the lesion in segment one. Pathological analysis demonstrated FNH. The second patient was a 21-year-old woman who presented with multiple liver lesions during follow-up for colon carcinoma. She underwent a laparoscopic right-sided hemicolectomy and was adjuvantly treated with capecitabine and oxaliplatin three years ago. Magnetic resonance imaging (MRI) was performed, and the lesions showed no signs of metastatic disease but were classified as FNH. Therefore, the decision was made to follow up the patient. In conclusion, the development of benign liver lesions could occur during follow-up of colon carcinoma and might be caused by oxaliplatin-induced changes to the liver parenchyma. Hence, it is important to distinguish these from metastatic liver disease.

3.
Microsc Res Tech ; 82(10): 1787-1801, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31329310

ABSTRACT

This article deals with the modeling and simulation of the vibration behavior of piezoelectric micro-cantilever (MC) based on the Timoshenko theory and using multi-scale (MTS) method in the air environment. In this regard, the results are compared with the previous literature, such as the finite element method and the MTS method. The analysis of the piezoelectric MC vibrating behavior is investigated in a dynamical mode including non-contact and tapping modes. The dynamics of this system is affected by interferential forces between probe tip and sample surface, such as van der Waals, capillary, and contact forces. According to the results, the forces applied to the probe tip reduce the amplitude and the resonance frequency. The simulation of surface topography in non-contact mode and tapping for rectangular and wedge-shaped roughness in the air environment are presented. Various experiments have been conducted in Ara research Company using the atomic force microscopy device in the amplitude mode. In the NSC15 Cantilever, the first natural frequency is derived from the results of the MC simulation based on Timoshenko beam theory, the practical results are 295.85 and 296.12 kHz, and the error rate is 0.09; at higher natural frequencies, the error rate has been increased. The γ f coefficient is a measure of the nonlinear effects on the system; the effect of the piezoelectric length and width on γ f coefficient is also investigated.

4.
Insights Imaging ; 10(1): 53, 2019 May 20.
Article in English | MEDLINE | ID: mdl-31111237

ABSTRACT

Cancer cells can escape the immune system by different mechanisms. The evasion of cancer cells from immune surveillance is prevented by immune checkpoint inhibitors, allowing the patient's own immune system to attack their cancer. Immune checkpoint inhibitors have shown improvement in overall survival for melanoma, lung cancer and renal cell carcinoma in clinical trials. Unfortunately, not all patients respond to this therapy.In cancer management, percutaneous ablation techniques are well established for both cure and local control of many tumour types. Cryoablation of the tumour tissue results in cell destruction by freezing. Contrary to heat-based ablative modalities, cryoablation induces tumour cell death by osmosis and necrosis. It is hypothesised that with necrosis, the intracellular contents of the cancer cells stay intact allowing the immune system to induce an immune-specific reaction. This immune-specific reaction can, in theory, also affect cancer cells outside the ablated tissue, known as the abscopal effect. Unfortunately, this effect is rarely observed, but when cryoablation is combined with immunotherapy, the effect of both therapies may be enhanced. Although several preclinical studies demonstrated a synergistic effect between cryoablation and immunotherapy, prospective clinical trials are needed to prove this clinical benefit for patients. In this review, we will outline the current evidence for the combination of cryoablation with immunotherapy to treat cancer.

6.
Cancer Invest ; 28(5): 452-8, 2010 Jun.
Article in English | MEDLINE | ID: mdl-19863344

ABSTRACT

It has been recently demonstrated that progranulin is overexpressed in ovarian cancer and that this protein is involved in the stimulation of cell proliferation, malignancy, and chemoresistance in ovarian cancer. The goal of the present study was to establish the differences in progranulin expression among normal, benign, and malignant ovarian tissues and to identify the signal transduction pathways activated by progranulin in an ovarian cancer cell line. Compared with benign tumors and normal ovarian tissue, progranulin mRNA and protein were overexpressed in malignant tumors. Survival analysis by the Kaplan-Meier method showed a correlation between high mRNA expression levels with poor survival outcome. Progranulin activated the MAPK-signaling pathway in NIH-OVCAR-3 cells. Progranulin expression may be potentially involved in the pathogenesis and malignant progression of ovarian cancer, and thus may represent a therapeutic target for this particular malignancy.


Subject(s)
Intercellular Signaling Peptides and Proteins/metabolism , Ovarian Neoplasms/metabolism , Ovary/metabolism , Adult , Aged , Aged, 80 and over , Apoptosis , Cell Line , Cell Line, Tumor , Cell Proliferation , Cell Survival , Female , Humans , Intercellular Signaling Peptides and Proteins/genetics , MAP Kinase Signaling System , Middle Aged , Ovarian Neoplasms/mortality , Progranulins
9.
Ultrasound Obstet Gynecol ; 33(3): 320-5, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19248004

ABSTRACT

OBJECTIVE: To develop a geometric model from computed tomographic (CT) images in non-pregnant women that would objectively reflect clinical head station in laboring patients, against which to test the accuracy of digital examinations. METHOD: CT scans were performed in 70 non-pregnant women to determine, using a geometric model, which angle in a mid-sagittal transperineal ultrasound (TPU) image best coincided with the mid-point of a line drawn between the ischial spines (zero station). Using a geometric algorithm, TPU angles were then assigned for other clinical stations (-5 to + 5). Finally, clinical station was assessed by digital examination and simultaneous TPU assessments in 88 laboring patients to see how closely the clinical examination correlated with the station calculated from the above geometric model. RESULTS: The mean angle between the long axis of the symphysis pubis and the mid-point of the line connecting the two ischial spines for the 70 non-pregnant subjects was 99 degrees . The geometric model developed allowed us to build an algorithm to assign a specific set of theoretical angles to each computed station. Relationships between digitally assessed fetal head station, TPU angle for each station, and the geometrical model created with CT data, are reported. Clinical digital assessment of station correlated poorly with computed station, especially at stations below zero, where it could have greater clinical impact. CONCLUSION: The TPU angle of 99 degrees correlated with zero station, and each station above or below this station could be assigned a specific corresponding angle for reference.


Subject(s)
Head/diagnostic imaging , Ischium/diagnostic imaging , Labor Stage, Second , Labor, Obstetric/physiology , Palpation/standards , Pubic Symphysis/diagnostic imaging , Adult , Algorithms , Female , Head/embryology , Humans , Ischium/anatomy & histology , Pregnancy , Pubic Symphysis/anatomy & histology , Tomography, X-Ray Computed
14.
Br J Anaesth ; 96(5): 583-6, 2006 May.
Article in English | MEDLINE | ID: mdl-16567343

ABSTRACT

BACKGROUND: Wake-up test can be used during posterior spinal fusion (PSF) to ensure that spinal function remains intact. This study aims at assessing the characteristics of the wake-up test during propofol-alfentanil (PA) vs propofol-remifentanil (PR) infusions for PSF surgery. METHODS: Sixty patients with scoliosis and candidates for PSF surgery were randomly allocated in either alfentanil (PA) or remifentanil (PR) group. After an i.v. bolus of alfentanil 30 microg kg(-1) in the PA group or remifentanil 1 microg kg(-1) in the PR group, anaesthesia was induced with thiopental and atracurium. During maintenance, opioid infusion consisted of alfentanil 1 microg kg(-1) min(-1) or remifentanil 0.2 microg kg(-1) min(-1), in the PA group and the PR group, respectively. All patients received propofol 50 microg kg(-1) min(-1). Atracurium was given to maintain the required surgical relaxation. At the surgeon's request, all infusions were discontinued. Patients were asked to move their hands and feet. Time from anaesthetic discontinuation to spontaneous ventilation (T(1)), and from then until movement of the hands and feet (T(2)), and its quality were recorded. RESULTS: The average T(1) and T(2) were significantly shorter in the PR group [3.6 (2.5) and 4.1 (2) min] than the PA group [6.1 (4) and 7.5 (4.5) min]. Quality of wake-up test, however, did not show significant difference between the two groups studied. CONCLUSION: Wake-up test can be conducted faster with remifentanil compared with alfentanil infusion during PSF surgery.


Subject(s)
Anesthetics, Combined , Anesthetics, Intravenous , Auditory Perception/drug effects , Spinal Cord Injuries/prevention & control , Spinal Fusion , Adolescent , Adult , Alfentanil , Analgesics, Opioid , Female , Humans , Intraoperative Care/methods , Male , Movement , Piperidines , Propofol , Reaction Time , Remifentanil , Scoliosis/surgery , Spinal Cord Injuries/diagnosis , Spinal Cord Injuries/etiology , Spinal Fusion/adverse effects
15.
J Radiol ; 87(2 Pt 1): 136-8, 2006 Feb.
Article in French | MEDLINE | ID: mdl-16484937

ABSTRACT

Clear cell sarcoma of the kidney rarely affects adults. It has an aggressive evolution, with a high rate of recurrence and mortality. We report the case of a 58 year old man with clear cell sarcoma of the kidney and discuss the benefit and value of medical imaging for management.


Subject(s)
Kidney Neoplasms/diagnosis , Sarcoma, Clear Cell/diagnosis , Humans , Male , Middle Aged
16.
J Radiol ; 86(5 Pt 1): 493-5, 2005 May.
Article in French | MEDLINE | ID: mdl-16114206

ABSTRACT

Glomus tumor is an uncommon benign neuromyoarterial tumor. It most frequently involves the fingers, and only rarely involves other sites. The clinical, imaging and therapeutic considerations regarding a glomangioma of the leg in a 65-year-old-man are reviewed.


Subject(s)
Glomus Tumor/diagnostic imaging , Leg/diagnostic imaging , Soft Tissue Neoplasms/diagnostic imaging , Aged , Humans , Male , Neoplasm Recurrence, Local/diagnostic imaging , Tomography, X-Ray Computed
17.
J Radiol ; 85(1): 51-3, 2004 Jan.
Article in French | MEDLINE | ID: mdl-15094642

ABSTRACT

Hydatid disease involves the bones in 0.5 to 2% of cases, with 44% of these cases at the level of the spine. The cervical spine is a rare location, with a risk of spinal cord compression and recurrences. The Authors report a case of a young male admitted for progressive quadriplegia secondary to cervical spine hydatidosis, extending towards the retropharynx that was evaluated by CT and MRI.


Subject(s)
Cervical Vertebrae , Echinococcosis/diagnosis , Magnetic Resonance Imaging , Pharyngeal Diseases/diagnosis , Spinal Cord Compression/diagnosis , Tomography, X-Ray Computed , Adult , Anthelmintics/therapeutic use , Cervical Vertebrae/pathology , Cervical Vertebrae/surgery , Combined Modality Therapy , Contrast Media , Diagnosis, Differential , Echinococcosis/pathology , Echinococcosis/surgery , Gadolinium , Humans , Male , Morocco , Neurologic Examination , Pharyngeal Diseases/pathology , Pharyngeal Diseases/surgery , Quadriplegia/etiology , Spinal Cord Compression/pathology , Spinal Cord Compression/surgery
18.
J Radiol ; 83(11): 1778-80, 2002 Nov.
Article in French | MEDLINE | ID: mdl-12469018

ABSTRACT

Soft tissue involvement by hydatid disease remains unusual (5%) even in endemic areas. Patients typically present late because disease progression is slow and often asymptomatic. The authors report the unusual imaging appearance in a 59 year old woman with a one year history of progressive diffuse painless swelling of the left thigh. Ultrasonography showed multiple anechoic and hypoechoic cystic lesions, some of which containing serpentine echogenic structures consistent with partly calcified membranes. CT and MRI confirmed a diagnosis of hydatid disease and were helpful to demonstrate the relationship between cysts and adjacent structures. Surgical management was performed early because of fistulization to the skin.


Subject(s)
Echinococcosis/diagnosis , Magnetic Resonance Imaging , Thigh , Tomography, X-Ray Computed , Ultrasonography , Cutaneous Fistula/parasitology , Diagnosis, Differential , Disease Progression , Echinococcosis/complications , Echinococcosis/surgery , Edema/parasitology , Female , Humans , Magnetic Resonance Imaging/methods , Middle Aged , Sensitivity and Specificity , Time Factors , Tomography, X-Ray Computed/methods , Ultrasonography/methods
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