Chromogranin A as Blood Marker in Cancer Patients
Condition: Gastric Neoplasms; Pancreatic Neoplasms; Small Intestinal Neoplasms; Colorectal Neoplasms
MeSH terms: Neoplasms; Colorectal Neoplasms; Pancreatic Neoplasms; Stomach Neoplasms; Intestinal Neoplasms
Study type: Observational

Summary: 
      Gastroentero-pancreatic neuroendocrine tumors (GEP-NETs) are a heterogenous group of
      neoplasms that arise from enterochromaffin cells of the gastrointestinal (GI) tract and
      pancreas. They account for 50-70% of all incident NETs. Due to the lack of symptoms in the
      early stage of disease and the frequency of nonspecific GI symptoms, GEP-NETs are difficult
      to diagnose.

      Identification of effective biomarkers (such as Chromogranin A) to improve GEP-NET diagnosis,
      as well as to assess treatment efficacy, relapse and prognosis, is important for improving
      outcomes for patients with GEP-NETs.

      The purpose of this study is to validate the performance of Brahms (BRAHMS) Chromogranin A II
      Kryptor (KRYPTOR) assay to monitor the course of disease in patients with well-defined
      GEP-NETs.
    

Detailed description: 
      A general characteristic for neuroendocrine tumors (NET) is expression of chromogranin A
      (CgA), which is released from neuroendocrine cells, occasionally together with cell specific
      hormones such as gastrin, insulin, somatostatin, and serotonin in functional tumors. Human
      CgA is an acidic 439 amino acid protein with a sequence containing several mono- and dibasic
      cleavage sites, and correspondingly, numerous fragments of CgA have been identified in tissue
      and plasma. CgA is critical to the formation of secretory granules that characterize NETs,
      and is therefore a useful marker for NETs.

      Plasma concentrations of CgA and/or CgA fragments are elevated in most NETs. Moreover, since
      plasma CgA concentrations seem to be closely related to tumor burden in humans, plasma CgA
      concentration is an important prognostic factor. As such, high plasma concentrations of CgA
      as well as a dramatic increase in plasma CgA within a short time period, is associated with a
      poorer prognosis. Plasma CgA has also been suggested to be useful in the follow-up of
      patients with NETs.

      Taken together, these observations support the notion that CgA is a promising biomarker
      candidate for monitoring treatment effectiveness and disease progression or regression.

      Participation in this clinical study requires no additional visits to the oncologist,
      radiology or the laboratory. All information needed for the study will be obtained during
      typical visits as recommended by the oncologist. Clinical assessment of patients with
      GEP-NETs (according to NCCN guidelines) is based on physical exam, imaging (CT or MRI scans)
      and laboratory parameters. The course of disease is followed by RECIST 1.1 categorization
      including the evaluation of tumor burden by imaging.
    

Intervention name(s): BRAHMS CgA II KRYPTOR
Intervention type(s): Diagnostic Test
Intervention description(s): The BRAHMS CgA II KRYPTOR kit is an automated immunofluorescent assay for the quantitative determination of the concentration of CgA in human serum.
The assay is to be used as an aid in monitoring disease progression during the course of disease and treatment in patients with GEP-NETs (grade 1 and grade 2).
Serial testing for patient BRAHMS CgA II KRYPTOR assay values should be used in conjunction with other clinical methods for monitoring GEP-NETs (grade 1 and grade 2).
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Adult patients with diagnosed well-differentiated G1 and G2 GEP-NETs
      
Biospecimen description: 
      Serum samples
    
Keywords: Endocrine tumors; Carcinoids; Functional NETs; Non-functional NETs; Immunoassay