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1.
Clin Gastroenterol Hepatol ; 18(9): 2081-2090.e9, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31887451

RESUMEN

BACKGROUND & AIMS: Liver biopsy is the reference standard for staging and grading nonalcoholic fatty liver disease (NAFLD), but histologic scoring systems are semiquantitative with marked interobserver and intraobserver variation. We used machine learning to develop fully automated software for quantification of steatosis, inflammation, ballooning, and fibrosis in biopsy specimens from patients with NAFLD and validated the technology in a separate group of patients. METHODS: We collected data from 246 consecutive patients with biopsy-proven NAFLD and followed up in London from January 2010 through December 2016. Biopsy specimens from the first 100 patients were used to derive the algorithm and biopsy specimens from the following 146 were used to validate it. Biopsy specimens were scored independently by pathologists using the Nonalcoholic Steatohepatitis Clinical Research Network criteria and digitalized. Areas of steatosis, inflammation, ballooning, and fibrosis were annotated on biopsy specimens by 2 hepatobiliary histopathologists to facilitate machine learning. Images of biopsies from the derivation and validation sets then were analyzed by the algorithm to compute percentages of fat, inflammation, ballooning, and fibrosis, as well as the collagen proportionate area, and compared with findings from pathologists' manual annotations and conventional scoring systems. RESULTS: In the derivation group, results from manual annotation and the software had an interclass correlation coefficient (ICC) of 0.97 for steatosis (95% CI, 0.95-0.99; P < .001); ICC of 0.96 for inflammation (95% CI, 0.9-0.98; P < .001); ICC of 0.94 for ballooning (95% CI, 0.87-0.98; P < .001); and ICC of 0.92 for fibrosis (95% CI, 0.88-0.96; P = .001). Percentages of fat, inflammation, ballooning, and the collagen proportionate area from the derivation group were confirmed in the validation cohort. The software identified histologic features of NAFLD with levels of interobserver and intraobserver agreement ranging from 0.95 to 0.99; this value was higher than that of semiquantitative scoring systems, which ranged from 0.58 to 0.88. In a subgroup of paired liver biopsy specimens, quantitative analysis was more sensitive in detecting differences compared with the nonalcoholic steatohepatitis Clinical Research Network scoring system. CONCLUSIONS: We used machine learning to develop software to rapidly and objectively analyze liver biopsy specimens for histologic features of NAFLD. The results from the software correlate with those from histopathologists, with high levels of interobserver and intraobserver agreement. Findings were validated in a separate group of patients. This tool might be used for objective assessment of response to therapy for NAFLD in practice and clinical trials.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Biopsia , Fibrosis , Humanos , Inflamación/patología , Hígado/patología , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología , Aprendizaje Automático , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/patología , Índice de Severidad de la Enfermedad
2.
BMC Gastroenterol ; 14: 60, 2014 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-24694003

RESUMEN

BACKGROUND: Ajmaline is a pharmaceutical agent now administered globally for a variety of indications, particularly investigation of suspected Brugada syndrome. There have been previous reports suggesting that repetitive use of this agent may cause severe liver injury, but little evidence exists demonstrating the same effect after only a single administration. CASE PRESENTATION: A 33-year-old man of Libyan origin with no significant past medical history underwent an ajmaline provocation test for investigation of suspected Brugada syndrome. Three weeks later, he presented with painless cholestatic jaundice which peaked in severity at eleven weeks after the test. Blood tests confirmed no evidence of autoimmune or viral liver disease, whilst imaging confirmed the absence of biliary tract obstruction. A liver biopsy demonstrated centrilobular cholestasis and focal rosetting of hepatocytes, consistent with a cholestatic drug reaction. Over the course of the next few months, he began to improve clinically and biochemically, with complete resolution by one year post-exposure. CONCLUSION: Whilst ajmaline-related hepatotoxicity was well-recognised in the era in which the drug was administered as a regular medication, clinicians should be aware that ajmaline may induce severe cholestatic jaundice even after a single dose administration.


Asunto(s)
Ajmalina/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Ictericia Obstructiva/inducido químicamente , Bloqueadores del Canal de Sodio Activado por Voltaje/efectos adversos , Adulto , Síndrome de Brugada/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Humanos , Ictericia Obstructiva/patología , Masculino , Índice de Severidad de la Enfermedad
3.
Histopathology ; 63(3): 316-24, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23837447

RESUMEN

AIMS: To examine factors that influence lymph node count and to study the relationship between nodal size and metastatic involvement in gastric cancer. METHODS AND RESULTS: Observational study comparing lymph node retrieval by manual nodal dissection (MND) and systematic fat blocking (SFB) from 114 gastrectomy specimens. The influence of lymph node retrieval method, patient characteristics, oncological factors and surgical approach on lymph node count were examined using regression models. The risk-adjusted cumulative sum chart method was also used to analyse lymph node count. The lymph node count increased during the course of this study (P < 0.005). Both pathologist and lymph node retrieval method were independent predictors for lymph node count. MND yielded lower lymph node counts than SFB (58 versus 66, P < 0.05). The pathologist influenced lymph node retrieval by MND (R(2) : 0.297-0.518, P < 0.0001), but not SFB (R(2) : 0.340-0.344, P > 0.05). The percentage of positive lymph nodes below 5 mm was 24.2% and 44.1% for MND and SFB, respectively, resulting in cancer upstaging (P = 0.037). CONCLUSIONS: Systematic fat blocking is associated with a higher total and positive lymph node yield compared to MND and is independent of the pathologist. Ignoring small lymph nodes can be a major cause for missing positive nodes, leading in turn to cancer down-staging.


Asunto(s)
Escisión del Ganglio Linfático/normas , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Gastrectomía , Humanos , Escisión del Ganglio Linfático/métodos , Escisión del Ganglio Linfático/tendencias , Estadificación de Neoplasias , Neoplasias Gástricas/secundario
4.
Prostate Cancer Prostatic Dis ; 26(2): 282-286, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-34845306

RESUMEN

BACKGROUND: Preoperative PSA, ISUP grade group (GG), prostate examination and multiparametric MRI (mpMRI) form the basis of prostate cancer staging. Unlike other solid organ tumours, tumour volume (TV) is not routinely used aside from crude estimates such as maximum cancer core length. The aim of this study is to assess the role of TV as a marker for oncological outcomes in high-risk non-metastatic prostate cancer. METHODS: A prospectively maintained database of patients undergoing minimally invasive (laparoscopic or robot-assisted laparoscopic) radical prostatectomy at a UK centre between 2007 and 2019 were analysed. A total of 251 patients with NCCN high or very high-risk prostate cancer were identified. Primary outcome measure was time to biochemical recurrence (BCR) and the secondary outcome was time to treatment failure (TTF). TV was measured on the pathological specimen using the stacking method. Multivariable cox regression analysis was used to identify factors predicting BCR and TFF. TV as a predictor of BCR and TFF was further analysed through time-dependent receiver operating characteristic (ROC) curves. Kaplan-Meier survival estimates were used to evaluate TV cut-off scores. RESULTS: Median follow up was 4.50 years. Four factors were associated with BCR and TFF on multivariable analysis (TV, pathological GG, pathological T stage, positive margin >3 mm). Area under the Curve (AUC) for TV as a predictor of BCR and TTF at 5 years was 0.71 and 0.75, respectively. Including all 4 variables in the model increased AUC to 0.84 and 0.85 for BCR and TFF. A 2.50 cm TV cut off demonstrated a significance difference in time to BCR, p < 0.001. CONCLUSIONS: Pathological tumour volume is an independent predictor of oncological outcomes in high risk prostate cancer but does not add significant prognostic value when combined with established variables. However, the option of accurate TV measurement on mpMRI raises the possibility of using TV as useful marker for preoperative risk stratification.


Asunto(s)
Próstata , Neoplasias de la Próstata , Masculino , Humanos , Próstata/diagnóstico por imagen , Próstata/cirugía , Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/cirugía , Carga Tumoral , Recurrencia Local de Neoplasia/patología , Prostatectomía/métodos , Antígeno Prostático Específico
5.
JAMA Surg ; 157(11): e223899, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36069888

RESUMEN

Importance: Cancers of the upper gastrointestinal tract remain a major contributor to the global cancer burden. The accurate mapping of tumor margins is of particular importance for curative cancer resection and improvement in overall survival. Current mapping techniques preclude a full resection margin assessment in real time. Objective: To evaluate whether diffuse reflectance spectroscopy (DRS) on gastric and esophageal cancer specimens can differentiate tissue types and provide real-time feedback to the operator. Design, Setting, and Participants: This was a prospective ex vivo validation study. Patients undergoing esophageal or gastric cancer resection were prospectively recruited into the study between July 2020 and July 2021 at Hammersmith Hospital in London, United Kingdom. Tissue specimens were included for patients undergoing elective surgery for either esophageal carcinoma (adenocarcinoma or squamous cell carcinoma) or gastric adenocarcinoma. Exposures: A handheld DRS probe and tracking system was used on freshly resected ex vivo tissue to obtain spectral data. Binary classification, following histopathological validation, was performed using 4 supervised machine learning classifiers. Main Outcomes and Measures: Data were divided into training and testing sets using a stratified 5-fold cross-validation method. Machine learning classifiers were evaluated in terms of sensitivity, specificity, overall accuracy, and the area under the curve. Results: Of 34 included patients, 22 (65%) were male, and the median (range) age was 68 (35-89) years. A total of 14 097 mean spectra for normal and cancerous tissue were collected. For normal vs cancer tissue, the machine learning classifier achieved a mean (SD) overall diagnostic accuracy of 93.86% (0.66) for stomach tissue and 96.22% (0.50) for esophageal tissue and achieved a mean (SD) sensitivity and specificity of 91.31% (1.5) and 95.13% (0.8), respectively, for stomach tissue and of 94.60% (0.9) and 97.28% (0.6) for esophagus tissue. Real-time tissue tracking and classification was achieved and presented live on screen. Conclusions and Relevance: This study provides ex vivo validation of the DRS technology for real-time differentiation of gastric and esophageal cancer from healthy tissue using machine learning with high accuracy. As such, it is a step toward the development of a real-time in vivo tumor mapping tool for esophageal and gastric cancers that can aid decision-making of resection margins intraoperatively.


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Tracto Gastrointestinal Superior , Humanos , Masculino , Anciano , Anciano de 80 o más Años , Femenino , Márgenes de Escisión , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/cirugía , Estudios Prospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirugía , Análisis Espectral/métodos , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirugía , Tracto Gastrointestinal Superior/patología
6.
Leuk Lymphoma ; 45(3): 609-11, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15160926

RESUMEN

Nodular lymphocyte predominant Hodgkin lymphoma is reported in 2 siblings with onset at the age of 47 in a woman of Indian ethnic origin and at the age of 52 in her younger brother. Although some cases of familial Hodgkin lymphoma can be related to inherited characteristics and others to Epstein-Barr virus infection, this is not so for familial nodular lymphocyte predominant Hodgkin lymphoma for which the aetiology and reason for the familial occurrence remain unknown.


Asunto(s)
Salud de la Familia , Enfermedad de Hodgkin/etiología , Ganglios Linfáticos/patología , Adulto , Edad de Inicio , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biopsia , Femenino , Enfermedad de Hodgkin/diagnóstico , Enfermedad de Hodgkin/tratamiento farmacológico , Humanos , Masculino , Hermanos , Tomografía Computarizada por Rayos X
8.
Case Rep Oncol Med ; 2012: 460749, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23150839

RESUMEN

Adult renal rhabdomyosarcoma is a rare subtype of renal sarcoma. We present a case of a renal mass treated with radical nephrectomy that subsequently was shown to be renal rhabdomyosarcoma. We discuss the clinical presentation, imaging findings, and histology for this case and review the available literature.

9.
J Med Case Rep ; 5: 229, 2011 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-21699676

RESUMEN

INTRODUCTION: Colonoscopic perforation is a rare but serious complication of colonoscopy. Factors known to increase the risk of perforation include colonic strictures, extensive diverticulosis, and friable tissues. We describe the case of a man who was found to have perforation of the sigmoid colon secondary to an undiagnosed connective tissue disorder (Ehlers-Danlos syndrome type IV) while undergoing surveillance for hereditary non-polyposis colorectal cancer. CASE PRESENTATION: A 33-year-old Caucasian man presented to our hospital with an acute abdomen following a colonoscopy five days earlier as part of hereditary non-polyposis colorectal cancer screening. His medical history included bilateral clubfoot. His physical examination findings suggested left iliac fossa peritonitis. A computed tomographic scan revealed perforation of the sigmoid colon and incidentally a right common iliac artery aneurysm as well. Hartmann's procedure was performed during laparotomy. The patient recovered well post-operatively and was discharged. Reversal of the Hartmann's procedure was performed six months later. This procedure was challenging because of dense adhesions and friable bowel. The histology of bowel specimens from this surgery revealed thinning and fibrosis of the muscularis externa. The patient was subsequently noted to have transparency of truncal skin with easily visible vessels. An underlying collagen vascular disorder was suspected, and genetic testing revealed a mutation in the collagen type III, α1 (COL3A1) gene, which is consistent with a diagnosis of Ehlers-Danlos syndrome type IV. CONCLUSIONS: Ehlers-Danlos syndrome type IV, the vascular type, is a rare disorder caused by mutations in the COL3A1 gene on chromosome 2q31. It is characterized by translucent skin, clubfoot, and the potentially fatal complications of spontaneous large vessel rupture, although spontaneous uterine and colonic perforations have also been reported in the literature. The present case presentation describes the identification of Ehlers-Danlos syndrome type IV in a patient with a non-spontaneous colonic perforation secondary to an invasive investigation for another hereditary disorder pre-disposing him to colorectal cancer. Invasive procedures such as arteriograms and endoscopies are relatively contra-indicated in Ehlers-Danlos syndrome type IV. Alternatives with a lower risk of perforation, such as computed tomographic colonography, need to be considered for patients requiring ongoing colorectal cancer surveillance. Furthermore, management of vascular aneurysms in patients with Ehlers-Danlos syndrome type IV requires consideration of the risks of endovascular stenting, as opposed to open surgical intervention, because of tissue friability. Genetic and reproductive counseling should be offered to affected individuals and their families.

10.
BMJ Case Rep ; 20092009.
Artículo en Inglés | MEDLINE | ID: mdl-21686624

RESUMEN

Leiomyomatosis peritonei disseminata is a condition seen uncommonly in states of oestrogen hypersecretion in women of childbearing age. There are no clear guidelines for the primary management and follow-up of these patients. Here, a rare case in a postmenopausal woman with a normal hormonal state who may be considered higher risk is presented, with a review suggesting a management pathway in these patients.

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