Tenosynovial giant cell tumor.

Tenosynovial Giant Cell Tumor (TGCT) is a group of typically benign lesions arising from the synovium of joints, bursae and tendon sheaths. Depending on their growth pattern and clinical course, they are divided into localized and diffuse types. It is predominantly caused by a mutation in the stromal cells of the synovial membrane leading to overexpression of the colony stimulating factor 1 that recruits CSF1R-expressing cells of the mononuclear phagocyte lineage into the tumor mass. The lesions contain mainly histiocyte-like and synovial cells accompanied by varying numbers of multinucleated giant cells, mononuclear cells, foam cells, inflammatory cells and hemosiderin deposits. The gold standard for detect- ing and monitoring the disease is MRI, where the characteristic hemosiderin accumulation can be best appreciated, but it is a histological examination that is most conclusive. The main treatment is surgical resection of all pathological tissue, but radio- and chemotherapy are also viable options for certain groups of patients.

[Perineural cysts]. / Torbiele okolokorzeniowe.

Perineural cyst (Tarlov cyst) is a lesion in a form of fluid-filled sacks, usually located within the nerve root sheath at the posterior root of a spinal nerve, whose wall is formed by: endoneurium, peripheral nerve fibers and ganglion cells and areolar tissue. Depending on the studied population, the frequency of lesion occurence was estimated at 1.5- 13.2%, with its significant majority occuring in women. Cyst development may be the result of ischemia, hemorrhage, inflammation or trauma. Cysts are usually asymptomatic theefore they are likely to bo detected accidentally. However, in approximately 1/4 of the cases, the cyst puts so much pressure on the nerve and the neighbouring nerve roots that it becomes symptomatic (causes pain). The presence of clinical symptoms may be an indication for conservative treatment (i.e. analgesics, rehablitation, cyst puncture) or surgery (usually laminectomy).

Pigmented villonodular synovitis.

Pigmented villonodular synovitis (PVNS) is a benign disease that rarely undergoes malignant transformation. There are two types of disease: localized (nodular tenosynovitis) and di used (pigmented villonodular synovitis/tenosynovitis) with intra- or extra-articular locations. The second one is limited to synovium of the burse (PVNB) or tendon sheath (PVNTS). The intraarticular lesions are usually located in the knee, hip, ankle and elbow joints. Histologically, PVNS is a tenosynovial giant cell tumor, characterized by proliferation of two types of mononuclear cells - predominantly small, histiocyte-like cells and larger cells with dense cytoplasm, reniform or lobulated nucleus, with accompanying multinucleated giant cells and macrophages overloaded with hemosiderin that give typical image on MRI - currently selected as a gold standard for its diagnosis. The classic X-ray and CT are non-specific but similar to ultrasound should be used to evaluate disease progression and treatment response if radiotherapeutic and pharmacological methods were selected for treatment. An open arthroscopic surgery could also be applied in selected cases.

[Epidemiology and risk factors of hepatocellular carcinoma]. / Epidemiologia i czynniki ryzyka rozwoju raka watrobowokomórkowego.

Primary liver neoplasms occurs relatively rarely in Poland. The most frequently occurring type of cancer is hepatocellular carcinoma (HCC), which globally constitutes 7% of all the occurrences of cancer. The incidence increases with age and is the highest in patients around the age of 70. It also varies significantly depending on the geographic location. The main factors that cause HCC are infection of HBV and HCV, whose genome integrates into the DNA of the host, causing mutations. The other factors include excessive alcohol consumption, contact or consumption of Aspergillus toxins as well as various metabolic disorders, such as α1-antitrypsin deficiency, hemochromatosis, tyrosinemia, porphyria, von Gierke disease and in person with gene mutation p.I148M of adiponutrin. HCC is usually detected incidentally, during ultrasound examination or during clinical diagnosis of liver failure. HCC can be diagnosed using computed tomography (CT) or magnetic resonance imaging (MRI), which is considered the most accurate diagnostic method. A core needle biopsy or the examination of the level of markers such as: alpha-fetoprotein (AFP), D-gamma-carboxy prothrombin (DCP), tumourassociated glycoprotein 72 (CA 72-4, TAG-72), are advised for a complete diagnostics.