Solitary fibrous tumor (SFT), also known as fibrous tumor of the pleura, is a rare mesenchymal tumor originating in the pleura or at virtually any site in the soft tissue including seminal vesicle. Approximately 78% to 88% of SFTs are benign and 12% to 22% are malignant. The World Health Organization (2020) classified SET as specific type of tumor in the category of malignant fibroblastic and myofibroblastic tumors. Signs and symptoms
About 80% of pleural SFTs originate in the visceral pleura, while 20% arise from parietal pleura. Although they are often very large tumors (up to 40 cm. in diameter), over half are asymptomatic at diagnosis. While some researchers have proposed that a SFT occupying at least 40% of the affected hemithorax be considered a "giant solitary fibrous tumor", no such "giant" variant has yet been recognized within the most widely used pleural tumor classification scheme.Some SFTs are associated with the paraneoplastic Doege–Potter syndrome, which is caused by tumor production of IGF-2. Pathophysiology
Recurrent somatic fusions of the two genes, NGFI-A–binding protein 2 (NAB2) and STAT6, located at chromosomal region 12q13, have been identified in solitary fibrous tumors. Treatment
The treatment of choice for both benign and malignant SFT is complete en bloc surgical resection. Prognosis
Prognosis in benign SFTs is excellent. About 8% will recur after first resection, with the recurrence usually cured after additional surgery.The prognosis in malignant SFTs is much more guarded. Approximately 63% of patients will have a recurrence of their tumor, of which more than half will succumb to disease progression within 2 years.
Methoxy polyethylene glycol-epoetin beta is the active ingredient of a drug marketed by Hoffmann-La Roche under the brand name Mircera. Mircera is a long-acting erythropoietin receptor activator (CERA) indicated for the treatment of patients with anaemia associated with chronic kidney disease. It is the first approved, chemically modified erythropoiesis-stimulating agent (ESA). Mircera is supplied as a solution in pre-filled syringes for intravenous or subcutaneous administration. Mircera was approved for use in Europe in July 2007 by the European Commission, in September 2007 by the Swissmedic, and in November 2007 by the U.S. Food and Drug Administration for use in the United States. Methoxy polyethylene glycol-epoetin beta is made from erythropoietin by chemically linking the N-terminal amino group or the ε-amino group of any lysine present in the protein with methoxy polyethylene glycol butanoic acid. The average molecular weight is approximately 60 kDa. The drug stimulates erythropoiesis by interacting with the erythropoietin receptor on progenitor cells in the bone marrow. It has a reduced receptor binding activity compared to other ESAs and but retains in vivo activity due to an extended serum half-life. It has an in vivo half-life of around 135 hours (5.6 days) as compared to darbepoetin alfa which has a half life of around 21 to 70 hours, the half life of which is three times that of the naturally occurring erthropoietin in the body. It is on the World Health Organizations List of Essential Medicines.