Articles
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1,116 results found
Article
Malignant peripheral nerve sheath tumor
Malignant peripheral nerve sheath tumors (MPNSTs) are forms of peripheral nerve sheath tumors occurring either de novo or arising from pre-existing tumors (e.g. neurofibromas, schwannomas etc.). Approximately half of such tumors are seen in individuals with neurofibromatosis type I (NF1), in suc...
Article
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...
Article
Superior vena cava obstruction
Superior vena cava obstruction (SVCO) can occur from extrinsic compression, intrinsic stenosis, or thrombosis of the superior vena cava. Malignancies are the main cause and are considered an oncologic emergency. Superior vena cava syndrome (SVCS) refers to the clinical syndrome with symptoms tha...
Article
Pleomorphic liposarcoma
Pleomorphic liposarcomas are high-grade malignant neoplasms arising from adipocytic tissues characterized by a variable number of pleomorphic lipoblasts and the absence of areas of well-differentiated liposarcoma and other lines of differentiation.
Epidemiology
Pleomorphic sarcomas are rare an...
Article
Breast neoplasms
Breast neoplasms consist of a wide spectrum of pathologies from benign proliferations, high-risk lesions, precursor lesions, to invasive malignancies. This article provides an overview for radiologists, with a focus on breast cancer.
For a summary article for medical students and non-radiologi...
Article
Free/total PSA ratio
The free/total PSA ratio (f/t PSA) is the simple mathematical ratio of the free prostate specific antigen (PSA) in blood serum over the total PSA in blood serum 1,2. It is expressed as a dimensionless quantity 4.
The lower the f/t PSA, the higher the probability of prostate cancer 5, however, d...
Article
Glioblastoma, IDH-wildtype
Glioblastomas (GBM) are the most common adult primary brain tumor and are aggressive, relatively resistant to therapy, and have a corresponding poor prognosis.
They typically appear as heterogeneous masses centered in the white matter with irregular peripheral enhancement, central necrosis, and...
Article
Autoimmune encephalitis
Autoimmune encephalitis, also known as autoimmune limbic encephalitis, is an antibody-mediated brain inflammatory process, typically involving the limbic system, although any part of the brain, and central nervous system more broadly, can be involved.
Autoimmune encephalitis can be divided broa...
Article
Prostate specific antigen
Prostate specific antigen (PSA) is currently used as a tumor marker for prostate cancer.
PSA is a 33-kilodalton glycoprotein produced in prostate epithelial cells. Its normal physiologic role is as a liquefying agent for seminal fluid; only a tiny amount leaks into the blood, so its normal seru...
Article
Pituitary carcinoma
Pituitary carcinomas or metastatic PitNET are rare tumors that are histologically indistinguishable from pituitary adenomas (PitNET) on imaging, defined only by the presence of central nervous system or systemic metastases.
Terminology
In the 5th edition of the WHO classification of CNS tumors...
Article
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...
Article
Tram-track sign (orbit)
Tram-track sign refers to the parallel thickening and enhancement around the optic nerve, and is most frequently seen in the setting of optic nerve sheath meningioma.
It may, however, also be seen in 1:
orbital pseudotumor
optic perineuritis
orbital sarcoidosis
orbital leukemia
orbital lym...
Article
Optic nerve sheath meningioma
Optic nerve meningiomas are benign tumors arising from the arachnoid cap cells of the optic nerve sheath and represent ~20% of all orbital meningiomas, the majority of which are direct extensions from intracranial meningiomas.
These tumors typically appear as masses within the optic nerve, iso...
Article
Pleomorphic adenoma of the salivary glands
Pleomorphic adenomas of the salivary glands, also known as benign mixed tumors (see below), are the most common salivary gland tumors. The salivary glands are the most common site of pleomorphic adenomas.
On imaging, they commonly present as well-circumscribed rounded masses, most commonly loca...
Article
Soft tissue sarcoma
Soft tissue sarcomas are a heterogeneous group of malignant tumors of mesenchymal origin (sarcoma) that originate from the soft tissues rather than bone. They are classified on the basis of tissue seen on histology. The more common sarcomas in the adult and pediatric populations are listed below...
Article
Asbestosis
Asbestosis is an occupational fibrotic lung disease associated with high levels of asbestos fiber inhalation. Fibrosis is lower lobe predominant and can progress. Even without progression the risk of lung cancer is increased. The presence of pleural plaques is variable 10.
Epidemiology
Asbest...
Article
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...
Article
Bone lesions with sequestrum
There are several bony lesions that can involve or produce a sequestrum.
They include:
Common
Brodie abscess: osteomyelitis
Less common
eosinophilic granuloma
certain soft tissue tumors (with bony extension)
undifferentiated pleomorphic sarcoma
lymphoma
metastasis (especially from brea...
Article
Hepatic metastases
Hepatic metastases are 18-40 times more common than primary liver tumors 6. Ultrasound, CT, and MRI are helpful in detecting hepatic metastases and evaluation across multiple post-contrast CT series, or MRI pulse sequences are necessary.
Epidemiology
The demographics of patients with liver me...
Article
Mediastinal lymph node enlargement
Mediastinal lymph node enlargement can occur from a wide range of pathologies and can be isolated or associated with lung pathology. Historically, a size cut-off of 10 mm short-axis diameter was used.
Terminology
The term mediastinal lymphadenopathy implies lymph node disease and is not synon...
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