Role of Abdominal and Pelvic CT Scans in Diagnosis of Patients with Immunotherapy-Induced Colitis.

Introduction: Colitis is one of the most common immune-related adverse events in patients receiving immune checkpoint inhibitors. Although radiographic changes on computed tomography (CT), such as mild diffuse bowel thickening, mesenteric fat stranding, and mucosal enhancement, have been reported, the utility of CT in diagnosis of patients with suspected immune-related colitis is not well documented. The aim of this retrospective study was to determine the value of CT scans in diagnosis of immunotherapy-induced colitis. Methods: CT scans of the abdomen and pelvis of 34 patients receiving immunotherapy who had a clinical diagnosis of immunotherapy-induced colitis and 19 patients receiving immunotherapy without clinical symptoms of colitis (controls) were evaluated. Segments of the colon (rectum, sigmoid, descending, transverse, ascending, and cecum) were assessed independently by two abdominal imaging specialists, blinded to the clinical diagnosis. Each segment was assessed for radiographic signs such as mucosal enhancement, wall thickening, distension, and periserosal fat stranding. The presence of any of the signs was considered radiographic evidence of colitis. Results: CT findings suggestive of colitis was seen in 20 of 34 patients with symptoms of colitis and in 5 of 19 patients without symptoms of colitis. The sensitivity, specificity, positive predictive value, and negative predictive value for colitis on CT were 58.8%, 73.7%, 80%, and 50%, respectively. Conclusions: We found that CT had a low sensitivity, specificity, and negative predictive value for the diagnosis of immunotherapy-induced colitis. We therefore conclude that CT has a limited role in the diagnosis of patients with suspected uncomplicated immune-related colitis.

Review of uterine fibroids: imaging of typical and atypical features, variants, and mimics with emphasis on workup and FIGO classification.

Uterine fibroids are the most common gynecologic neoplasm. Although non-degenerated fibroids are easily identifiable on imaging, degenerated fibroids, fibroid variants, and fibroids with unusual growth patterns can constitute a diagnostic dilemma. Identification of these abnormal morphologic features can alter the diagnosis of presumed uterine fibroids and hence change management plans. This article reviews the typical and atypical radiologic imaging features of uterine fibroids, with an emphasis on the pitfalls, mimics, and radiologically identifiable features that can alter clinical management plans.

Defining Diagnostic Criteria for Prostatic Ductal Adenocarcinoma at Multiparametric MRI.

Background Prostatic ductal adenocarcinoma (DAC) is an aggressive histologic variant of prostate cancer that often warrants multimodal therapy and poses a significant diagnostic challenge clinically and at imaging. Purpose To develop multiparametric MRI criteria to define DAC and to assess their diagnostic performance in differentiating DAC from prostatic acinar adenocarcinoma (PAC). Materials and Methods Men with histologically proven DAC who had multiparametric MRI before radical prostatectomy were retrospectively identified from January 2011 through November 2018. MRI features were predefined using a subset of nine DACs and then compared for men with peripheral-zone DACs 1 cm or greater in size and men with matched biopsy-confirmed International Society of Urological Pathology grade group 4-5 PAC, by four independent radiologists blinded to the pathologic diagnosis. Diagnostic performance was determined by consensus read. Patient and tumor characteristics were compared by using the Fisher test, t-tests, and Mann-Whitney U test. Agreement (Cohen κ) and sensitivity analyses were also performed. Results There were 59 men with DAC (median age, 63 years [interquartile range, 56, 67 years]) and 59 men with PAC (median age, 64 years [interquartile range, 59, 69 years]). Predefined MRI features, including intermediate T2 signal, well-defined margin, lobulation, and hypointense rim, were detected in a higher proportion of DACs than PACs (76% [45 of 59] vs 5% [three of 59]; P < .001). On consensus reading, the presence of three or more features demonstrated 76% sensitivity, 94% specificity, 94% positive predictive value [PPV], and 80% negative predictive value [NPV] for all DACs and 100% sensitivity, 95% specificity, 81% PPV, and 100% NPV for pure DACs. The DACs and PACs showed no difference in contrast enhancement (100% vs 100%; P >.99, median T2 signal intensity (254 vs 230; P = .99), or apparent diffusion coefficient (median, 677 10-6 mm2/sec vs 685 10-6 mm2/sec; P = .73). Conclusion The presence of intermediate T2 signal, well-defined margin, lobulation, and/or hypointense rim, together with restricted diffusion and contrast enhancement at multiparametric MRI of the prostate, suggests prostatic ductal adenocarcinoma rather than prostatic acinar adenocarcinoma. © RSNA, 2022 Online supplemental material is available for this article.

Peutz-Jeghers Syndrome and the Role of Imaging: Pathophysiology, Diagnosis, and Associated Cancers.

The Peutz-Jeghers Syndrome (PJS) is an autosomal dominant neoplastic syndrome defined by hamartomatous polyps through the gastrointestinal tract, development of characteristic mucocutaneous pigmentations, and an elevated lifetime cancer risk. The majority of cases are due to a mutation in the STK11 gene located at 19p13.3. The estimated incidence of PJS ranges from 1:50,000 to 1:200,000. PJS carries an elevated risk of malignancies including gastrointestinal, breast, lung, and genitourinary (GU) neoplasms. Patients with PJS are at a 15- to 18-fold increased malignancy risk relative to the general population. Radiologists have an integral role in the diagnosis of these patients. Various imaging modalities are used to screen for malignancies and complications associated with PJS. Awareness of various PJS imaging patterns, associated malignancies, and their complications is crucial for accurate imaging interpretation and patient management. In this manuscript, we provide a comprehensive overview of PJS, associated malignancies, and surveillance protocols.

Novel deep learning-based noise reduction technique for prostate magnetic resonance imaging.

INTRODUCTION: Magnetic resonance imaging (MRI) has played an increasingly major role in the evaluation of patients with prostate cancer, although prostate MRI presents several technical challenges. Newer techniques, such as deep learning (DL), have been applied to medical imaging, leading to improvements in image quality. Our goal is to evaluate the performance of a new deep learning-based reconstruction method, "DLR" in improving image quality and mitigating artifacts, which is now commercially available as AIRTM Recon DL (GE Healthcare, Waukesha, WI). We hypothesize that applying DLR to the T2WI images of the prostate provides improved image quality and reduced artifacts. METHODS: This study included 31 patients with a history of prostate cancer that had a multiparametric MRI of the prostate with an endorectal coil (ERC) at 1.5 T or 3.0 T. Four series of T2-weighted images were generated in total: one set with the ERC signal turned on (ERC) and another set with the ERC signal turned off (Non-ERC). Each of these sets then reconstructed using two different reconstruction methods: conventional reconstruction (Conv) and DL Recon (DLR): ERCDLR, ERCConv, Non-ERCDLR, and Non-ERCConv. Three radiologists independently reviewed and scored the four sets of images for (i) image quality, (ii) artifacts, and (iii) visualization of anatomical landmarks and tumor. RESULTS: The Non-ERCDLR scored as the best series for (i) overall image quality (p < 0.001), (ii) reduced artifacts (p < 0.001), and (iii) visualization of anatomical landmarks and tumor. CONCLUSION: Prostate imaging without the use of an endorectal coil could benefit from deep learning reconstruction as demonstrated with T2-weighted imaging MRI evaluations of the prostate.

Li-Fraumeni Syndrome and Whole-Body MRI Screening: Screening Guidelines, Imaging Features, and Impact on Patient Management.

OBJECTIVE: Li-Fraumeni syndrome (LFS) is a rare autosomal-dominant inherited syndrome containing a germline mutation in the TP53 gene, which predisposes to oncogenesis. Leukemia and tumors of the brain, soft tissues, breasts, adrenal glands, and bone are the most common cancers associated with this syndrome. Patients with LFS are very susceptible to radiation, therefore the use of whole-body MRI is recommended for regular cancer screening. It is important to recognize the common tumors associated with LFS on MRI, and it is also important to be aware of the high rate of false-positive lesions. CONCLUSION: Whole-body MRI is useful for the detection of cancer in patients who come for regular screening; however, it is associated with pitfalls about which the radiologist must remain aware.

Improved Computed Tomography Contrast Injection Rates Through Implantable Chest Power Ports.

OBJECTIVE: The aim of this study was to optimize chest port contrast injections using stepwise improvements. METHODS: Ex vivo injections were tested. Two hundred scans using power port injections were then evaluated. RESULTS: The highest flow rate was achieved using a 19G access needle, larger diameter tubing, and warmed contrast.The mean injection rates in baseline and postimprovement groups were 2.7 ± 0.4 and 4.8 ± 0.4 mL/s, respectively (P < .0001). CONCLUSION: Component optimization of the port apparatus can maximize contrast flow rates.

Pancreatitis and PDAC: association and differentiation.

The discrimination of mass-forming chronic pancreatitis (MFCP) from pancreatic ductal adenocarcinoma (PDAC) is a central diagnostic dilemma. It is important to differentiate these entities since they have markedly different prognoses and management. Importantly, the appearance of these two entities significantly overlaps on a variety of imaging modalities. However, there are imaging features that may be suggestive of one entity more than the other. MFCP and PDAC may show different enhancement patterns on perfusion computed tomography (CT) and/or dynamic contrast-enhanced MRI (DCE-MRI). The duct-penetrating sign on magnetic resonance cholangiopancreatography (MRCP) is more often associated with MFCP, whereas abrupt cutoff with upstream dilatation of the main pancreatic duct and the double-duct sign (obstruction/cutoff of both the common bile duct and pancreatic duct) are more often associated with PDAC. Nevertheless, tissue sampling is the most reliable method to differentiate between these entities and is currently generally necessary for management.

Dose variations in tumor volumes and organs at risk during IMRT for head-and-neck cancer.

Many head-and-neck cancer (HNC) patients treated with radiotherapy suffer significant anatomical changes due to tumor shrinkage or weight loss. The purpose of this study was to assess dose changes over target volumes and organs at risk during intensity-modulated radiotherapy for HNC patients. Sixteen HNC IMRT patients, all requiring bilateral neck irradiation, were enrolled in the study. A CTplan was performed and the initial dose distribution was calculated. During the treatment, two subsequent CTs at the 15th (CT15) and 25th (CT25) fractions were acquired. The initial plan was calculated on the CT15 and CT25, and dose-volume differences related to the CTplan were assessed. For target volumes, mean values of near-maximun absorbed dose (D2%) increased at the 25th fraction, and doses covering 95% and 98% of volume decreased significantly at the 15th fraction. Contralateral and ipsilateral parotid gland mean doses increased by 6.1% (range: -5.4, 23.5%) and 4.7% (range: -9.1, 22.3%), respectively, at CT25. The D2% in the spinal cord increased by 1.8 Gy at CT15. Mean absorbed dose increases at CT15 and CT25 were observed in: the lips, 3.8% and 5.3%; the oral cavity, 3.5% and 2.5%; and lower middle neck structure, 1.9% and 1.6%. Anatomical changes during treatment of HNC patients affect dose distribution and induce a loss of dose coverage to target volumes and an overdosage to critical structures. Appropriate organs at risk have to be contoured and monitored in order to know if the initial plan remains suitable during the course of the treatment. Reported dosimetric data can help to identify patients who could benefit from adaptive radiotherapy.

Induction of differentiation of embryonic stem cells into insulin-secreting cells by fetal soluble factors.

Cell signals produced during pancreas embryogenesis regulate pancreatic differentiation. We show that the developing pancreas releases soluble factors responsible for in vitro endocrine pancreatic differentiation from embryonic stem cells (ESCs). A mouse D3 ESC line was transfected with a human insulin promoter/betageo/phosphoglycerate kinase-hygromycin-resistant construct. To direct differentiation, cells were cultured for 7 days to form embryoid bodies and then plated for an additional 7 days. During this 14-day period, besides eliminating leukemia inhibitory factor, cells were cultured in low serum concentration with the addition of conditioned media from embryonic day-16.5 pancreatic buds. Islet cell differentiation was studied by the following: (a) X-gal staining after neomycin selection, (b) BrdU (bro-modeoxyuridine) studies, (c) simple and double immunohistochemistry for insulin, C-peptide, and glucose transporter 2 (Glut-2), (d) reverse transcription-polymerase chain reaction for insulin and pancreas duodenum homeobox 1 (PDX-1), (e) insulin and C-peptide content and secretion assays, (f) intraperitoneal glucose tolerance test, (g) electrophysiology (patch-clamp studies in inside-out configuration), and (h) transplantation of differentiated cells under the kidney capsule of streptozotocin-diabetic mice. The differentiated ESCs showed the following: changes in the mRNA levels of insulin and PDX-1; coexpression of insulin, C-peptide, and Glut-2; glucose and tolbutamide-dependent insulin and C-peptide release; K-channel activity regulated by ATP; and normalization of blood glucose levels after transplantation into diabetic mice and hyperglycemia after graft removal. In this study, we establish a battery of techniques that could be used together to properly characterize islet cell differentiation. Moreover, identification of factors released by the developing pancreas may be instrumental in engineering beta cells from stem cells.

Evaluación económica en salud: de la investigación a la toma de decisiones / Economic evaluation in health: from research to decision making

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The cost-effectiveness of policies for the safe and appropriate use of injection in healthcare settings.

OBJECTIVE: Poor injection practices transmit potentially life-threatening pathogens. We modelled the cost-effectiveness of policies for the safe and appropriate use of injections in ten epidemiological subregions of the world in terms of cost per disability-adjusted life year (DALY) averted. METHODS: The incidence of injection-associated hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infections was modelled for a year 2000 cohort over a 30-year time horizon. The consequences of a "do nothing" scenario were compared with a set of hypothetical scenarios that incorporated the health gains of effective interventions. Resources needed to implement effective interventions were costed for each subregion and expressed in international dollars (I dollars). FINDINGS: Worldwide, the reuse of injection equipment in the year 2000 accounted for 32%, 40%, and 5% of new HBV, HCV and HIV infections, respectively, leading to a burden of 9.18 million DALYs between 2000 and 2030. Interventions implemented in the year 2000 for the safe (provision of single-use syringes, assumed effectiveness 95%) and appropriate (patients-providers interactional group discussions, assumed effectiveness 30%) use of injections could reduce the burden of injection-associated infections by as much as 96.5% (8.86 million DALYs) for an average yearly cost of 905 million I dollars (average cost per DALY averted, 102; range by region, 14-2293). Attributable fractions and the number of syringes and needles required represented the key sources of uncertainty. CONCLUSION: In all subregions studied, each DALY averted through policies for the safe and appropriate use of injections costs considerably less than one year of average per capita income, which makes such policies a sound investment for health care.

Nuclear KATP channels trigger nuclear Ca(2+) transients that modulate nuclear function.

Glucose, the principal regulator of endocrine pancreas, has several effects on pancreatic beta cells, including the regulation of insulin release, cell proliferation, apoptosis, differentiation, and gene expression. Although the sequence of events linking glycemia with insulin release is well described, the mechanism whereby glucose regulates nuclear function is still largely unknown. Here, we have shown that an ATP-sensitive K(+) channel (K(ATP)) with similar properties to that found on the plasma membrane is also present on the nuclear envelope of pancreatic beta cells. In isolated nuclei, blockade of the K(ATP) channel with tolbutamide or diadenosine polyphosphates triggers nuclear Ca(2+) transients and induces phosphorylation of the transcription factor cAMP response element binding protein. In whole cells, fluorescence in situ hybridization revealed that these Ca(2+) signals may trigger c-myc expression. These results demonstrate a functional K(ATP) channel in nuclei linking glucose metabolism, nuclear Ca(2+) signals, and nuclear function.

Tratamiento quirurgico de la hernia hiatal asociada a ulcus duodenal: Operacion de Nissen y vagotomia supraselectiva / Surgical treatment of the hiatal hernia associated with duodenal ulcus: Nissen's operation and supraselective vagotomy

Se presenta un estudio retrospectivo sobre el tratamiento quirurgico de la hernia hiatal asociada a ulceras duodenales, empleandose para el tratamiento simultaneo la funduplicatura de Nissen y la vagotomia supraselectiva. El trabajo recoge la experiencia del autor, obtenida en el tratamiento quirurgico de la hernia hiatal segun la tecnica de Nissen en 220 casos, de los cuales 38 (17.27%) presentaban ulcera duodenal asociada. Estos enfermos fueron seguidos desde hace 15 anos hasta hace seis meses. Cuatro pacientes presentaron algunos sintomas digestivos postoperatorios, los otros 34 (89.47%) estan asintomaticos en la actualidad. Concluimos que el tratamiento quirurgico combinado de la funduplicatura de Nissen con la vagotmia supraselectiva es eficaz y seguro en la hernia hiatal asociada a ulceras duodenales

Enfermedades diverticulares del colon / Colonic diverticulitis diseases

No es la edad del enferno la que nos limita la posibilidad de hacer una intervención quirúrgica, sino el estado de los órganos internos evaluados en forma consciente antes de las colectomías. Si el estado de los órganos internos lo permite, hemos realizado intervenciones quirúrgicas donde, además de las colectomías se ha hecho una corrección de una hernia hiatal o se ha procedido en el mismo acto quirúrgico a una vagotomía supraselectiva o a una anastomosis bilio-digestiva