Blood Tests in Patients with NETs:
Bloodwork 101 (Guide from ISI): Patient guide for blood tests; see Chapter 4 starting on Page 107.
Note section on 5-HIAA Plasma test as an alternate test to the 24 hour HIAA urine collection.
Neurokinin A (NKA) has been shown to be a powerful independent predictor of a poor prognosis in well-differentiated midgut NETs. Patients with NKA levels below 50 pg/mL have an excellent 3 year survival rate compared to patients with values over 50.
Pancreastatin is a fragment of the chromogranin A molecule and may be a more sensitive predictor of carly changes in tumor burden compared to chromogranin A.
Pathology Report in Patients with NETS - You should know your KI-67 Index:
The diagnosis of a NET primarily depends on microscopic analysis of a tissue sample obtained from a tumor. The tissue may be obtained by a needle biopsy or from a surgical biopsy or excision. Once the pathologist confirms the diagnosis of a NET, an additional analysis is performed to determine the Ki-67 index of the tumor, a measure of the number of cells in a tumor that are dividing (proliferating). The Ki-67 Index determines the tumor Grade which is important for understanding the potential tumor growth rate and as a factor making treatment decisions.
Ki-67 Categories in NETs:
Grade 1: <3
Grade 2: 3-30
Grade 3: >30
Grades 1 and 2 are considered “low grade”; Grade 3 is “high grade” and these are called neuroendocrine carcinomas. The approach to imaging and treatment are different for Grade 3 NETs.