Articles

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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...
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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...
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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...
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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...
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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...
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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...
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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...
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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...
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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...
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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 ...
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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...
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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...
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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...
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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...
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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...
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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...
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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 ...
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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...
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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...
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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...

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