Articles
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1,118 results found
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
Lucent/lytic bone lesion - differential diagnosis (mnemonic)
Mnemonics for the differential diagnosis of lucent/lytic bone lesions include:
FEGNOMASHIC
FOG MACHINES
They are anagrams of each other and therefore include the same components. They are by no means exhaustive lists, but are a good start for remembering a differential for a lucent/lytic bone...
Article
Rhabdoid meningioma
Rhabdoid meningioma is a rare and aggressive subtype of meningioma. Rhabdoid morphology is associated with a poor prognosis, regardless of tumor histogenesis. It resembles other types of rhabdoid tumors with a great tendency for recurrence 1,2. Extensive necrosis in rhabdoid meningioma might be ...
Article
Pineal parenchymal tumor of intermediate differentiation
Pineal parenchymal tumors of intermediate differentiation (PPTID) are, as the name suggests, tumors that fall between pineocytoma (well-differentiated, WHO grade 1) and pineoblastomas (poorly differentiated, WHO grade 4). They are considered WHO grade 2 or 3 tumors 4. Their radiographic appearan...
Article
Gastric neuroendocrine tumor
Gastric neuroendocrine tumors (GNETs), previously known as gastric carcinoids, are rare primary neoplasms that arise from enterochromaffin-like cells of the gastric mucosa.
Epidemiology
GNETs account for less than 2% of all gastric neoplasms and up to 10% of all gastrointestinal neuroendocrine...
Article
Epidural spinal cord compression scale
The epidural spinal cord compression (ESCC) scale, sometimes known eponymously as the Bilsky scale, is used to assess the degree to which vertebral body metastasis compromises the spinal canal and whether cord compression is present. It may serve as a guide as to when intervention (radiotherapy ...
Article
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...
Article
Marginal zone lymphoma
Marginal zone lymphomas are a group of low grade non-Hodgkin lymphoma that arise from the marginal zone of B cell germinal follicles in lymph nodes. There are three types of marginal zone lymphomas depending on the site of origin, namely mucosa-accosiated lymphoid tissue (MALT), splenic and extr...
Article
Low-grade appendiceal mucinous neoplasm
Low-grade appendiceal mucinous neoplasms (LAMN), previously known as appendiceal mucinous cystadenomas, are rare mucinous tumors of the appendix showing low-grade cytologic atypia, cf. high-grade appendiceal mucinous neoplasms.
Terminology
Considerable controversy still exists on mucinous neo...
Article
Salivary duct carcinoma
Salivary duct carcinomas are a subtype of primary salivary gland tumor. Salivary duct carcinomas show high rates of metastasis and recurrence.
Epidemiology
Salivary duct carcinomas represent 5-10% of salivary gland malignancies and can arise de novo or out of a pleomorphic adenoma 1,2. They t...
Article
Inferior vena cava leiomyosarcoma
Inferior vena cava leiomyosarcomas are the most common type of retroperitoneal leiomyosarcoma and most common primary malignancy of the inferior vena cava (IVC).
Epidemiology
Three-quarters of cases occur in women, usually aged 40-60 years 2.
Clinical presentation
When symptomatic, patients ...
Article
Mediastinal yolk sac tumor
Mediastinal yolk sac tumors or yolk sac tumors of the mediastinum are malignant non-seminomatous germ cell tumors primarily growing in the mediastinum.
Terminology
The term ‘endodermal sinus tumor’ is not recommended.
Epidemiology
Mediastinal yolk sac tumors are rare mediastinal tumors. In a...
Article
Squamous cell carcinoma (urinary bladder)
Squamous cell carcinoma (SCC) of the urinary bladder is rare, nevertheless SCC is the most common type of non-transitional cell carcinoma involving the bladder 2. Most bladder cancers are transitional/urothelial cell carcinomas. SCC is much more common where Schistosomiasis infections are more p...
Article
Anterior mediastinal germ cell tumors
Germ cell tumors are one of the causes of an anterior mediastinal mass, and any of the germ cell histologies may be identified. They can therefore be divided histologically into:
mediastinal seminoma
non-seminomatous germ cell tumors (NSGCT)
embryonal carcinoma
choriocarcinoma
yolk sac tumo...
Article
Cookie bite bone metastases
Cookie bite bone metastases are characterized by small focal eccentric lytic external cortical destruction in long tubular bones. This type of destruction is typically described for metastases from lung cancer, however, they can also occur with other tumors.
Article
Jewett-Strong-Marshall tumor staging system
Jewett-Strong-Marshall tumor staging system for bladder cancer is of historic interest only and has been superseded by the TNM staging system.
stage 0: epithelial
stage A: submucosal invasion but no involvement of muscle i.e. lamina propria
stage B: bladder wall or muscle invasion
B1: superf...
Article
Assessment of thyroid lesions (general)
Assessment of thyroid lesions is commonly encountered in radiological practice.
Thyroid mass
hyperplastic/colloid nodule/nodular hyperplasia: 85%
adenoma
follicular: 5%
others: rare
primary thyroid cancer (carcinoma)
papillary: 60-80% of carcinomas
follicular: 10-20%
medullary: 5%
anap...
Article
Positron emission tomography
Positron emission tomography (PET) is a modern non-invasive imaging technique for quantification of radioactivity in vivo. It involves the intravenous injection of a positron-emitting radiopharmaceutical, waiting to allow for systemic distribution, and then scanning for detection and quantificat...
Article
Primary bone lymphoma
Primary bone (skeletal/osseous) lymphoma (PBL) is a less common manifestation of lymphoma than secondary involvement from disseminated lymphoma. It is rare, accounting for <5% of bone tumors and <1% of non-Hodgkin lymphoma.
Terminology
PBL is defined as the presence of lymphoma isolated to one...
Article
Immunosuppression
Immunosuppression is the impairment of the body's immune system which can alter the ability of the body's defense mechanisms to prevent diseases, particularly certain infections, including opportunistic infections, and cancers.
Terminology
Patients with immunosuppression are said to be immuno...
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