Articles

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1,114 results found
Article

Rectal cancer response assessment

Assessment of rectal cancer response to therapy, which may be chemotherapy, radiotherapy, or a combination, relies on the synthesis of clinical, endoscopic and radiologic evaluation.  The purpose of neoadjuvant therapy is to downstage the tumor, to facilitate surgical resection, and reduce loca...
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Choledochal cyst

Choledochal cysts represent congenital cystic dilatations of the biliary tree. Diagnosis relies on excluding other conditions as a cause of biliary duct dilatation, e.g. tumor, gallstone, inflammation. Epidemiology Choledochal cysts are rare, with an incidence of 1:100,000-150,000. Although th...
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Pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma, frequently referred to as pancreatic cancer, makes up the vast majority (~90%) of all pancreatic neoplasms and remains a disease with a very poor prognosis and high morbidity. Epidemiology Pancreatic cancer accounts for 22% of all deaths due to gastrointestina...
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Mastectomy

Mastectomy is a surgical treatment for breast cancer in which the entire breast tissue is removed through a surgical procedure as opposed to a wide local excision. Sometimes, adjacent structures, such as lymph nodes, are removed to prevent recurrence or metastasis. In some cases, mastectomy is d...
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Gynecologic Imaging-Reporting and Data System (GI-RADS)

The Gynecologic Imaging-Reporting and Data System (GI-RADS) is a reporting system that was created for reporting the findings in adnexal masses based on transvaginal ultrasonography. Classification Findings are classified into five categories 1: GI-RADS 1 normal ovaries identified and no adn...
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Superficial CD34-positive fibroblastic tumor

Superficial CD34-positive fibroblastic tumors (SCPFT) or PRDM10-rearranged soft tissue tumors are rare low-grade mesenchymal neoplasms of the dermis and subcutis 1-3 that have been just added to the WHO classification of soft tissue tumors in 2020 2,3. Epidemiology Superficial CD34-positive fi...
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Polymorphous low grade neuroepithelial tumor of the young

Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is an epileptogenic tumor of children and young adults. They are often considered part of the heterogeneous group of tumors known as long-term epilepsy-associated tumors (LEATs). Terminology First described in 2016 1, polymorpho...
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Circumferential resection margin

Circumferential resection margin (CRM) is a term used to denote the standard plane of excision of total mesorectal excision, used for resection of rectal cancers. The anatomic correlate is the mesorectal fascia. The distance between tumor tissue or satellite tumor deposits and the mesorectal fas...
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Left hemicolectomy

Left hemicolectomy is a surgical procedure in which splenic flexure, descending colon, and a portion of the sigmoid colon are removed for radical treatment of various pathologies affecting the descending colon. Indications colon cancer inflammatory bowel disease isolated left diverticular di...
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High-grade astrocytoma with piloid features

High-grade astrocytoma with piloid features (HGAP) is a rare tumor most commonly encountered in the posterior fossa of adults, especially those with neurofibromatosis type 1. It appears heterogeneous and has a relatively poor prognosis.  Epidemiology Due to the small number of patients reporte...
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Desmoid tumor

Desmoid tumors are benign, non-inflammatory fibroblastic tumors with a tendency for local invasion and recurrence post resection. They are sometimes considered a locally aggressive proliferative disease within the family of soft-tissue sarcomas but, metastasis is uncommon 7,11.  Terminology Th...
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Neuroblastoma (staging)

There are two methods of neuroblastoma staging; the International Neuroblastoma Risk Group Staging System (INRGSS, based on imaging of pre-treatment patients), and the International Neuroblastoma Staging System (INSS, based on the outcomes of surgery). International Neuroblastoma Risk Group St...
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Diffuse brainstem glioma (historical)

Diffuse brainstem gliomas or diffuse intrinsic pontine gliomas was a term used to describe infiltrating astrocytomas arising in the brainstem, usually in children. It is no longer recognized as a distinct entity, removed from the 2016 update to the WHO classification of CNS tumors replaced by a ...
Article

Plexiform neurofibroma

Plexiform neurofibroma is an uncommon variant of neurofibroma, a benign tumor of peripheral nerves (WHO grade I), arising from a proliferation of all neural elements. Plexiform neurofibromas are essentially pathognomonic of neurofibromatosis type 1 (NF1). Unlike small sporadic localized neurofib...
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Neuroblastoma

Neuroblastomas are tumors of neuroblastic origin. Although they may occur anywhere along the sympathetic chain, the vast majority arise from the adrenal gland. They represent the most common extracranial solid childhood malignancy and are the third commonest childhood tumor after leukemia and b...
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Splenic metastases

Splenic metastases are relatively rare on imaging and are more commonly encountered at autopsy. Typically they are part of a widespread metastatic disease. Epidemiology The rate of splenic metastases varies between 1-10% of autopsy studies, depending on whether microscopic or macroscopic metas...
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Bone marrow

Bone marrow is ubiquitous throughout the skeleton, primarily composed of hematopoietic cells and fat cells between bony trabeculae and fibrous retinacula. It performs numerous physiological functions and dynamically changes during normal aging and in response to stressors and pathology. Although...
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Fetal lung interstitial tumor

Fetal lung interstitial tumor (FLIT) is a proposed designation for a rare primary lung mass detected prenatally or when the patient is up to 3 months old. Epidemiology Fetal lung interstitial tumors have a slight predominance in boys 1. Clinical presentation It can present with varying degre...
Article

Rectal MRI (an approach)

Rectal MRI is a key imaging investigation in the diagnosis, staging and follow up of rectal cancer. An increase in the utility of rectal MRI as been driven by the recognition of the mesorectum as a distinct anatomic compartment containing and limiting the margins of the rectum, and forming a sur...
Article

Volume doubling time

The volume doubling time (VDT) is an important volumetric parameter primarily used in lung cancer screening and follow-up by chest CT. Volume doubling time is defined as the time required for a growing nodule to double its volume. A longer VDT suggests a more benign course, whilst a short VDT is...

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