Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
1,116 results found
Article
PSA density
The PSA density (PSAD) is calculated at diagnosis and is the serum prostate-specific antigen (PSA) level (ng/mL) divided by the prostate gland's volume (mL), resulting in a value in the units ng/mL2 1. Prostate volume is calculated from TRUS measurements, MRI measurements or, less commonly, rese...
Article
Thymic carcinoma
Thymic carcinoma is a part of the malignant spectrum of thymic epithelial tumors, along with malignant thymomas and neuroendocrine carcinomas.
Epidemiology
Patients are typically 50 to 70 years of age at presentation 9.
Pathology
The incidence of paraneoplastic syndromes is thought to be low...
Article
Ommaya reservoir
Ommaya reservoir, also known as Ommaya shunt, is a device for repetitive access to the intrathecal space, consisting of an intraventricular catheter connected to a reservoir (port) implanted beneath the scalp. It is used for intrathecal administration of medication such as chemotherapy (mainly i...
Article
Squamous cell carcinoma of the lung
Squamous cell carcinoma (SCC) is one of the non-small cell carcinomas of the lung, second only to adenocarcinoma of the lung as the most commonly encountered lung cancer.
Epidemiology
Squamous cell carcinoma accounts for ~30-35% of all lung cancers and in most instances is due to heavy smokin...
Article
Head and neck squamous cell carcinomas
Head and neck squamous cell carcinomas (HNSCC) are the most common histologic type of head and neck cancer. While the term may include any squamous cell carcinoma of the head and neck, common usage focuses on those of mucosal origin, i.e., squamous cell carcinoma of the upper aerodigestive tract...
Article
Protoplasmic astrocytoma (historical)
Protoplasmic astrocytoma is a historical term previously applied to an uncommon variant of diffuse adult-type astrocytomas.
Terminology
The term was removed in the updated 4th edition (2016) of the WHO classification of CNS tumors, with these tumors folded into what is now referred to as astro...
Article
Inferior vena caval thrombosis
Inferior vena caval thrombosis is an essential diagnosis while evaluating any neoplastic lesion, or portal hypertension. It is also important to differentiate bland thrombus from tumor thrombus.
Clinical features
A patient can present with many features which include
bilateral pedal edema
Bu...
Article
Testicular cancer
Testicular cancers are the most common malignancy in men between the ages of 20 and 34 years.
Epidemiology
Testicular cancer is uncommon, accounting for less than 1% of all internal organ malignancies 2.
The commonest histology of the tumor varies with the age of affected individuals. Over 90...
Article
Pineoblastoma
Pineoblastomas are tumors that are best thought of as small round blue cell tumors located in the pineal region and thus, they closely resemble (both on imaging and on histology) medulloblastomas and retinoblastomas. They are the most aggressive and highest grade tumor among pineal parenchymal t...
Article
Adult fibrosarcoma
Adult fibrosarcomas are rare, malignant and highly aggressive fibroblastic soft tissue tumors. They constitute a diagnosis of exclusion.
Epidemiology
Adult fibrosarcomas by definition are rare and make up around 1% of soft tissue sarcomas. They are mostly seen in middle-aged people within the ...
Article
Anastomosing hemangioma
Anastomosing hemangiomas are benign vascular neoplasms consisting of thin-walled anastomosing vessels. These lesions have been just added to the WHO classification of soft tissue tumors in 2020 as a separate entity 1-3
Epidemiology
Anastomosing hemangiomas are rare lesions with a wide range of...
Article
Peripheral intermediate and high-grade chondrosarcoma
Peripheral chondrosarcomas grade 2 and 3 are malignant intermediate and high-grade chondrogenic neoplasms originating from the bony surface in the chondral cap of pre-existing osteochondromas as a result of malignant transformation, thus the name secondary peripheral chondrosarcoma 1,2. Secondar...
Article
Ovarian cancer (staging)
The most commonly adopted ovarian cancer staging system is the FIGO staging system. The staging system is from 2014 1:
CT is considered the best imaging modality for staging ovarian cancer 4.
stage I: tumor limited to the ovaries
stage Ia:
tumor limited to one ovary
capsule intact
no tu...
Article
NTRK-rearranged soft tissue neoplasm
NTRK-rearranged soft tissue neoplasms (emerging), lipofibromatosis-like neural tumors or NTRK-positive tumor-resembling peripheral nerve sheath tumors are a group of rare molecularly defined spindle cell neoplasms excluding infantile fibrosarcoma 1.2. The tumors form a provisional category of un...
Article
Reporting and Data Systems (disambiguation)
There has been a proliferation of Reporting and Data Systems (RADS), which have been proposed - and in many cases widely adopted - as standardized systems for the reporting of imaging of various body organs, often, but certainly not always, with a focus on oncological disease 2. These systems al...
Article
Pancoast tumor
Pancoast tumor, also known as superior sulcus tumor, refers to a relatively uncommon situation where a primary lung cancer arises in the lung apex and invades the surrounding soft tissues. Classically a Pancoast syndrome results, but in actuality this is only seen in one quarter of cases.
Term...
Article
Tumor pseudoprogression (lung cancer)
Radiologic tumor pseudoprogression on imaging denotes an imaging appearance of tumor response where the tumor first exhibits findings suggestive of progression (i.e. growth, new lesions). However, during sustained therapy, response is eventually demonstrated 1.
Epidemiology
With the advent of ...
Article
Inflammatory leiomyosarcoma
Inflammatory leiomyosarcomas are malignant tumors with smooth muscle differentiation and a prominent inflammatory infiltrate that were recognized as a distinct entity by the WHO in 2020 1-3.
Epidemiology
Inflammatory leiomyosarcomas are very rare lesions with most cases seen in adults with a p...
Article
Chordoma
Chordomas are uncommon malignant tumors of the axial skeleton that account for 1% of intracranial tumors and 4% of all primary bone tumors.
They originate from embryonic remnants of the primitive notochord (earliest fetal axial skeleton, extending from the Rathke's pouch to the tip of the cocc...
Article
Cystic lesions of the pancreas (differential)
The differential for cystic lesions of the pancreas includes:
unilocular
pancreatic pseudocyst
intraductal papillary mucinous neoplasm (IPMN)
serous cystadenoma uncommonly uni/macrolocular
simple pancreatic cyst
cystic neuroendocrine tumor of the pancreas
diffuse pancreatic cysts
pancrea...