Overall, metastases have or will develop in up to 40% of individuals with UPS. These metastases are reported to occur in lung (40% to 55% of cases) and less commonly in other sites such as lymph nodes near the primary tumor, brain, pancreas, and heart. Neoplastic Fever
A review study conducted in China of 183 individuals with UPS reported that 7 (3.83%) individuals (age 51 to 73 years; median age 62.8 years) had a subtype of the paraneoplastic syndrome termed neoplastic fever, i.e. these individuals suffered continuous, disabling fevers. Their tumors  were located within a thigh muscle (4 cases), the upper arm (2 cases), or the lower leg (1 case). Compared to 89 individuals (median age 59.1 years) with a similar distribution of their UPS tumors, individuals with the neoplastic syndrome had similar tumor recurrence rates (57.14% vs 53.93% for the two respective groups) but a lower metastasis rate (14.29% vs 44.94%) and a higher 3-year survival rate (85.71% vs 59.55%). Fever symptoms disappeared in all patients after surgical removal of their tumors. It is suggested that individuals with UPS and neoplastic fever have a more favorable prognosis than individuals with UPS that do not evidence such fevers. Pathology
UPS is a diagnosis of exclusion (a diagnosis reached by the process of elimination) because the histopathology of this disorders tumors is non-specific. UPS tumor cells are undifferentiated (i.e. do not resemble any particular cell type) and pleomorphic (i.e. highly variable in size, shape, and/or color) when examined microscopically.
Such measurements can be useful to avoid central nervous system toxicity in any person receiving large doses of the drug on a chronic basis, but they are especially relevant to patients with kidney failure, who may accumulate the drug due to reduced urinary excretion rates. Manufacture
The production of benzylpenicillin involves fermentation, recovery and purification of the penicillin.The fermentation process of the production of benzylpenicillin creates the product. The presence of the product in solution inhibits the reaction and reduces the product rate and yield. Thus, in order to obtain the most product and increase the rate of reaction, it is continuously extracted. This is done by mixing the mold with either glucose, sucrose, lactose, starch, or dextrin, nitrate, ammonium salt, corn steep liquor, peptone, meat or yeast extract, and small amounts of inorganic salts.The recovery of the benzylpenicillin is the most important part of the production process because it affects the later purification steps if done incorrectly. There are several types of techniques used to recover benzyl penicillin: aqueous two-phase extraction, liquid membrane extraction, microfiltration, and solvent extraction. Extraction is more commonly used in the recovery process.In the purification step, the benzylpencillin is separated from the extraction solution. This is normally done by using a separation column. Synonyms
Penicillin II (old UK nomenclature for naming penicillins)

References
External links
"Benzylpenicillin". Drug Information Portal. U.S. National Library of Medicine.