For some time now, I’ve been watching the development of PET scans for Neuroendocrine Neoplasms (NENs).  I use the term ‘Neoplasms’ because there are different strategies for well and poorly differentiated types, Neuroendocrine Tumour (NET) and Neuroendocrine Carcinoma (NEC) respectively.

It’s known that most NETs have somatostatin receptors which makes tumours be seen better on somatostatin receptor-based imaging e.g. 68Ga-DOTATATE or 64Cu DOTATATE, but more aggressive types tend not to have working somatostatin receptors and are better seen on regular PET, i.e. 18F-FDG PET/CT.   However, nothing in NENs is simple and there’s always outliers.  This has been highlighted since the addition of a Grade 3 Well Differentiated NET into the equation.

The variable clinical outcome of patients with G2 & G3 well diff Gastroenteropancreatic Neuroendocrine Tumours (GEP NETs) makes the selection of an optimal treatment strategy challenging. Initial data suggests that high DOTATATE uptake and low FDG uptake are suggestive of low-grade disease, with an indolent course and most likely react well to somatostatin receptor-based therapies. Conversely, low DOTATATE uptake and high FDG uptake are suggestive of high-grade/ aggressive disease and a different therapeutic path might be required, e.g. chemotherapy.

I was therefore interested to see a Canadian trial looking at this overlapping area.  The trial, entitled Combined 68Ga-DOTATATE and 18F-FDG PET/CT Imaging in Patients With Well-differentiated, G2-G3, Gastroenteropancreatic (GEP)-Neuroendocrine Tumours (NETs) is a 2 year pilot study based in Toronto (Princess Margaret Cancer Centre).

References:

1.  Canadian Partner Against Cancer clinical trials repository “Dual Tracer (68Ga-DOTATATE and 18F-FDG) PET Imaging in G2 & G3 Gastroenteropancreatic Neuroendocrine Tumours”. Click here.
2. NIH ClinicalTrials.gov – NCT04804371 – Click here.

If you can see it, you can detect it – read more about imaging for Neuroendocrine Cancer – click here.