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High Grade Neuroendocrine Carcinoma Explained

Mar 7, 2023

Dr Nick Coupe, Medical Oncologist, Oxford University Hospital NHS Foundation Trust talks to Neuroendocrine Cancer UK about high grade neuroendocrine carcinomas.


What is High Grade Neuroendocrine Cancer?

Grade is an essential assessment and measurement of how neuroendocrine cancer cells are developing, growing, dividing and reproducing.

The grade may be determined by counting the cells that are dividing (called mitotic count or MiB1) but more often a test called Ki-67 is used – often expressed as a percentage (%).

Ki67 is a protein present in cells and is involved in cell growth and division. By using this protein to stain cancer cells, an assessment can be made as to how slowly or quickly the cancer cells are likely to grow and spread. So a result of less than 3% indicates that very few cells are actively growing and reproducing, therefore the overall rate of growth would be relatively slow. The higher the percentage the quicker growth can occur.

Typically Neuroendocrine Tumours (NETs) have a lower Ki67 than Neuroendocrine Carcinomas (NECs).

High Grade Categories

Grading is then divided into 4 specific categories – depending on growth rate (and cancer cell appearance – also known as differentiation).

However – Neuroendocrine Carcinoma (NEC) will require a different treatment plan than used in most Neuroendocrine Tumours (NETs) – because of the rate of cell growth and the cell differentiation (well vs poorly).

Whilst some High Grade Neuroendocrine Tumours (that is 3a) may benefit from some of the specific tests and treatments used in NEC, Neuroendocrine Carcinomas may benefit more from some of the tests and treatments used in more commonly known cancers – for example chemotherapy.

For further support and information including; differences, genetics and treatment, click here.