Pancreatic duct adenocarcinoma is a highly aggressive carcinoma that is associated with a poor prognosis. Detection of novel biological markers that are specifically over expressed in pancreatic duct adenocarcinoma and their subsequent targeting by anti cancer therapeutic modalities may improve patient's survival.

Pancreatic duct adenocarcinoma (PDAC) is a deadly neoplasm that showed current increase in its occurrence. There are many challenges in PDAC; the tumor is frequently associated with perineural invasion and angioinvasion, these lead to early metastasis.Another important challenge is that the tumor is associated with extensive fibrosis that prevents arrival of chemotherapeutic agents. Most modern anti-cancer therapeutic modalities depend on the biologic signature of the tumor. Human epidermal growth factor receptor-2 (HER-2) is a cell surface protein that is associated with enhanced cellular proliferation. HER-2 has been detected and successfully targeted in many human carcinomas as breast and gastric cancers. we aimed to evaluate the potential cancer-promoting effect of HER-2 in PDAC, in order to detect any possible benefits of its targeting by future therapeutic modalities.

Inclusion Criteria:

1. Cases of PDAC who underwent radical operations.
2. Tissue blocks with sufficient material.
3. Cases with available clinical data.

Exclusion Criteria:

1. Cases of pancreatic carcinoma other than PDAC.
2. Patients who received preoperative chemotherapy or radiotherapy.
3. Patients with PDAC who were diagnosed by tru-cut biopsies only and didn't undergo radical operations.
4. Cases with insufficient/destructed material.
5. Patients with inadequate clinical data.

• This study will be performed on archived formalin-fixed, paraffin-embedded tissue blocks that belonged to 37 patients who were admitted to Assuit and Sohag Oncology Centers and Sohag university hospital from January, 1st, 2017 to December, 31st, 2020. Patients' complaints included obstructive jaundice, abdominal pain and vomiting. Radiological assessment revealed heterogeneous suspicious pancreatic lesions from which tru-cut biopsies were obtained and examined by the standard staining method; hematoxylin and eosin (H&E). Cases diagnosed as pancreatic carcinoma on the basis of tru-cut biopsies underwent pancreaticoduodenectomy (Whipple procedure) or distal pancreatectomy, depending on tumor location.