Due to the neuroendocrine nature of pancreatic cancer, the researchers are interested in developing an early screening technique involving hormonal and molecular biomarkers through routine blood tests. PanNETs (pancreatic neuroendocrine tumors) are classified into functional tumors, which have symptoms related to excessive hormone secretion, and non-functional tumors, which do not secrete hormones and therefore do not exhibit associated symptoms. In functional tumors, measurement of hormones such as pancreatic polypeptide, gastrin, proinsulin, insulin, glucagon, and vasoactive intestinal peptide can determine if cancerous cells are involved in hypersecretion (Ro et al., 2013). Up to 60% of PanNETs are non-functional, which may pose a challenge to the researchers. However, 85% of PanNETs have an elevated blood marker, which may allow for further research and scrutiny of biomarkers to accomplish this goal (Jensen et al., 2009).
Comments
Flow of ideas
The ideas as presented don't seem to move smoothly from one to another. Try reorganizing the paragraph to achieve a better flow. Also you use "biomarker" (twice) and "blood marker" (once). Are these the same? Different?
more specific
try to add a little more detail to certain aspects, such as in the beginning you say "the researches" are interested in early pancreatic cancer screening techniques but never go onto to mention who these researches being referred to are.
Topic Sentence
Your topic sentence seems to be a little long and I think cutting it down would make it more clear. At the moment, it includes some "background info" about pancreatic cancer (that it is neuroendocrine in nature). Instead of including "Due to the neuroendocrine nature of pancreatic cancer" you can just start with what the researchers are interested in and then talk about the neuroendocrine nature of pancreatic cancer and why this is important for PanNETs.
comment
This is a very results heavy paragraph and there are some run on sentences so I would try and reorganize this as much as you can. Giving a result and then explaining it a little more in detail before giving the next result or fact may help out.