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Introduction to Cancer
Published in David E. Thurston, Ilona Pysz, Chemistry and Pharmacology of Anticancer Drugs, 2021
The multiple genetic changes that result in cancer may take many years to accumulate. During this time, the biological behavior of the premalignant cells slowly changes from the properties of normal cells to cancer-like properties. Premalignant tissue can have a distinctive appearance under the microscope, and among the distinguishing traits are an increased number of dividing cells, variation in nuclear size and shape, variation in cell size and shape, loss of specialized cell features, and loss of normal tissue organization. Dysplasia is an example of an abnormal type of excessive cell proliferation characterized by a loss of normal tissue arrangement and cell structure in premalignant cells. These early neoplastic changes are distinct from hyperplasia, a reversible increase in cell division caused by an external stimulus, such as a hormonal imbalance or chronic irritation. The most severe cases of dysplasia are referred to as carcinoma in situ, meaning an uncontrolled growth of cells that remains in the original location and has not progressed to invading other tissues. Nevertheless, a carcinoma in situ may develop into an invasive malignancy and is usually removed surgically, if possible. The various mechanisms of cellular DNA damage are described below.
Epithelial Precancerous and Borderline Lesions: Diagnosis and Screening
Published in Jeremy R. Jass, Understanding Pathology, 2020
The term dysplasia is associated with a number of practical difficulties. Its meaning varies in different pathological contexts. For example, it may be used to describe abnormal embryological development without neoplastic potential in organs such as the kidney. In the present context, dysplasia relates to a precancerous epithelial change falling short of malignancy (pre-invasive or benign neoplasia). Dysplasia may be mimicked by tissues undergoing repair or regeneration in response to a variety of inflammatory stimuli. This is a common problem in practice. Benign epithelial neoplasms show dysplasia by definition, but are classified according to the type of neoplasm (see Chapter 22). Small biopsies from the surface of a cancer may be underdiagnosed as dysplasia. In some tissues, for example breast and endometrium, dysplasia is manifested by a combination of epithelial overgrowth (hyperplasia) and cytological atypia. These lesions are usually described as hyperplasia with atypia rather than as dysplasia. In the cervix and prostate the term ‘intra-epithelial neoplasia’ is preferred to dysplasia. In short, the term dysplasia is subject to non-standardised use as well as abuse.
Basic Science and Molecular Oncology
Published in Manit Arya, Taimur T. Shah, Jas S. Kalsi, Herman S. Fernando, Iqbal S. Shergill, Asif Muneer, Hashim U. Ahmed, MCQs for the FRCS(Urol) and Postgraduate Urology Examinations, 2020
Paul Cleaveland, Vijay Sangar, Noel Clarke
Dysplasia is a pre-malignant condition where there is abnormal cell growth, cellular atypia and abnormal differentiation. It can be a reversible process in its early stage but once it becomes severe it can progress to neoplasia. Metaplasia a process where one type of differentiated cell transforms into another differentiated cell type. This process is reversible. It is an adaptive response of a tissue to changes in the environment so that the tissue can withstand these changes.
Prevalence of human papillomavirus infection in Brazilian women living with HIV: a systematic review and meta-analysis
Published in Expert Review of Anti-infective Therapy, 2022
Brenda Evelin Barreto da Silva, Lígia Mara Dolce de Lemos, Marcus Vinicius de Aragão Batista, Carlos Anselmo Lima, Paulo Ricardo Martins-Filho, Victor Santana Santos
Data were extracted using standardized tables and included author, publication year, Brazilian state and region, study design, characteristics of the studied subjects, study setting (inpatient or outpatient), HPV detection method (polymerase chain reaction [PCR], PCR and sequencing, PCR and hybridization, PCR-restriction fragment length polymorphism [RFLP] and hybridization), pregnancy status (non-pregnant, pregnant, both pregnant and non-pregnant and unknown), sample size, number of HPV-positive samples, the proportion of cases with high-risk HPV, HPV genotypes identified and frequency. In addition, we extracted the proportion of HR HPV by type of cervical lesion. For the analysis, we categorized the cervical lesions as: (i) negative for intraepithelial lesion or malignancy (NILM), (ii) dysplasia, which included low- and high‐grade squamous intraepithelial cervical lesions and atypical squamous or glandular cells, and (iii) carcinoma, when invasive cervical cancer had occurred. These categories were based on the cytological and/or histological findings reported by the included studies.
Long term outcomes of sporadic large fundic gland polyps: a single-center experience
Published in Scandinavian Journal of Gastroenterology, 2021
Abdul Mohammed, Rajat Garg, Sushrut Trakroo, Amandeep Singh, Madhusudhan R. Sanaka
Our study has many limitations. First, with retrospective studies, temporal relationship is frequently difficult to assess. Although our study indicated that obesity could be a potential risk factor in developing FGPs, direct causation cannot be validated. Similarly, reflux-like symptoms appear to be predominantly associated with large sporadic FGPs. However, this is likely related to the widespread use of PPIs in patients with GERD. Second, three patients in our study cohort developed dysplasia on follow-up. We cannot sufficiently explain these findings, but the number of study subjects affected is significantly low enough to be entirely due to chance. Third, our research data is derived from a population without dysplasia at index endoscopy. It does not represent the entire population of patients with fundic gland dysplasia. Fourth, the prevalence of sporadic FGPs in our study is higher (3.3%) when compared to reported literature. This is likely related to selection bias. Finally, since there are no guidelines pertaining to the follow-up of large FGPs, all of our study population did not undergo follow-up endoscopy procedures. Hence, the natural history of all polyps cannot be elucidated.
Colorectal cancer surveillance with chromoendoscopy in inflammatory bowel disease: results from a real-life experience
Published in Scandinavian Journal of Gastroenterology, 2021
Cristina Rubín de Célix, María Chaparro, José Andrés Moreno, Cecilio Santander, Javier P. Gisbert
The patients’ characteristics were analyzed in a univariate study according to whether they showed dysplasia or not. Regarding qualitative variables, percentages were calculated (95% confidence interval). As for quantitative variables, arithmetic mean and standard deviation were calculated. Categorical variables were compared by chi-square test (χ2), while quantitative variables were tested by either Student’s t-test or Wilcoxon according to whether the values followed a normal distribution or not. In the multivariate study, the development of dysplasia was considered as the dependent variable, while the independent variables were those which had shown statistical significance in the univariate study, as well as those variables which were clinically relevant. Clinical and demographic variables were included in the multivariate study, and the data for each patient were analyzed. On the other hand, morphologic and histologic characteristics of the detected polyps were analyzed by chromoendoscopy.