بایگانی برچسب برای: Cytology

Mediastinal.Lesions.Diagnostic.Pearls.[taliem.ir]

Mediastinal Lesions

Establishing the diagnosis of mediastinal tumors is viewed as challenging. Why? One reason is that these are relatively rare conditions, meaning that very few physicians have a large experience. This is compounded by the fact that the number of different tumors and conditions is large, thus further segmenting mediastinal tumors into multiple even smaller subgroups. Furthermore, the fundamental nature of mediastinal lesions is quite varied, ranging from fulminant to indolent malignant tumors and from benign conditions with little impact on a patient’s life to life-threatening benign lesions. In addition, the features of a mediastinal lesion that are most useful to suggesting or establishing a diagnosis vary, including clinical presentation, imaging haracteristics, and microscopic appearance. There is a strong need from a management perspective to establish the diagnosis with a reasonable degree of confidence before a treatment intervention, yet the optimal approach to obtaining tissue is varied and depends on the suspected diagnosis. Finally, most clinicians lack a structure of how to approach mediastinal tumors, and often explore various avenues (i.e., imaging, biopsy) without a clear understanding of what is at the top of their differential diagnosis list and their rationale for a particular approach (e.g., liquid vs. tissue biopsy).
Diagnostic.Liquid-Based.Cytology.[taliem.ir]

Diagnostic Liquid-Based Cytology

Liquid-based preparations (LBP) are increasingly being used for both gynecologic and non-gynecologic (non- gyn) cytology including fne needle aspiration (FNA). Although the diagnostic criteria used for conventional preparations can also be applied to LBP, an accurate interpretation of liquid-based slides requires familiarity with the background, architectural, and cytological alterations to avoid misdiagnosis .The types of LBP include SurePath [(SP), formally known as AutoCyte PREP, BD Diagnostics TriPath, Burlington, NC, USA] and ThinPrep [(TP), Hologic, Marlborough, MA, USA] and Millipore Filter (Bedford, MA, USA) and Liqui-PREP (LGM International, Fort Lauderdale, FL, USA). Currently, only SP and TP have FDA approval since they are the more commonly used LBP. The TP and SP preparations were approved for cervicovaginal (Pap test) cytology in 1996 and 1999, respectively, and both have since also been used for non-gynecological cytology including fne needle aspiration (FNA). Both TP and SP are also FDA-approved for high-risk human papillomavirus (HPV) testing of Pap tests. HPV test can also be performed on SP specimens after laboratories have performed internal validation. The published results have been shown comparable HPV performance of SP to TP. All illustrations depicted in this book are either SP or TP. Details of these commonly used LBP have been extensively published in the literature and also appear in the subsequent section of this chapter and in organ-specifc chapters.
Pediatric.Cytopathology.A.Practical.Guide.[taliem.ir]

Pediatric Cytopathology

Fine needle aspiration (FNA) is a reliable, minimally invasive, cost effective technique for obtaining samples from superficial and deep mass lesions for pathologic evaluation. Despite these advantages, physicians in the USA have been slow to embrace FNA as a primary diagnostic modality in the pediatric population . Obstacles to the acceptance and use of FNA include diagnostic challenges posed by the overall rarity and spectrum of tumors seen in children and adolescents, the experience and biases of clinicians and pathologists, and practical and technical considerations. Cytopathologists who are experienced in the performance and interpretation of FNAs may have limited familiarity with the spectrum and morphologic appearances of tumors seen in the pediatric population. Conversely, pediatric pathologists who are familiar with the histologic features and differential diagnosis of tumors encountered in children and adolescents often have little experience performing and/or interpreting FNAs. Likewise, clinicians who have extensive experience performing endoscopic or endobronchial ultrasound guided FNAs may have little experience with endoscopy or bronchoscopy of pediatric patients, and vice versa. These factors can impact the quality of the specimen and/or interpretation and lead to the need for a second procedure in order to arrive at a definitive diagnosis, thereby limiting the value of FNA as a diagnostic modality . Practical considerations include the cognitive and emotional maturity of the child or adolescent, and the need for immobilization, sedation, or anesthesia. Alone or in combination, these and other challenges and limitations have contributed to reluctance on the part of both pathologists and clinicians to promote the use of FNA as a primary diagnostic modality in the pediatric population.