Methods and compositions involving miR-135B for distinguishing pancreatic cancer from benign pancreatic disease

A method of treating a patient that has pancreatic ductal adenocarcinoma (PDAC) comprising:

• a) measuring by reverse-transcriptase polymerase chain reaction (RT-PCR) from a fine needle aspirate (FNA) pancreatic sample from the patient the level of expression of up to 11 different miRNAs that include at least miR-135b and at least 4 of the following diff pair miRNAs:
• miR148a, miR-130b, miR-196a, miR-24, miR-375, and miR-96, wherein at least one of the miRNAs is a biomarker miRNA and one is a comparative miRNA and miR-217 is not one of the miRNAs;
• b) determining a diff pair value for diff pairs:
• miR135b/miR-24, miR130b/miR-135b;
• miR-135b/miR-148a;
• miR-148a/miR-196a;
• miR-135b/miR-96;
• miR-375/miR-135b and optionally miR-130b/miR-24 and,
• c) analyzing the diff pair values using a computer performing linear discriminate analysis, wherein the linear discriminate identifies the patient as having PDAC;
• and
• d) treating the identified patient with chemotherapy, radiotherapy, surgery, or immunotherapy to treat the PDAC.