Bassam Sonbol, Oncologist at Mayo Clinic Arizona, shared a post by Thor Halfdanarson, Professor of Oncology at Mayo Clinic School of Medicine, shared a post on X, adding:
“Another study reported on therapy-related myeloid neoplasms (t-MN) after PRRT/RPT with Lu-177 dotatate.
Multiple studies have now shown repeatedly the grim prognosis, often around a year after diagnosis, in patients where prognosis is usually estimated in years and in some instances >a decade.
PRRT can cause hematological toxicity likely from marrow irradiation, and possibly also from direct targeting of somatostatin receptors expressed on subsets of hematopoietic stem/progenitor cells. In addition, patients with bone metastases may have higher risk as well.
The hematologic toxicity is most commonly mild and reversible, with most patients having their counts recover within weeks to a few months. However, some patients develop persistent hematologic toxicity with cytopenias lasting more than 6 months.
If you do a bone marrow on those, you might find mutations along with this cytopenia, but not enough to meet criteria for malignancy, consistent with a therapy-related clonal cytopenia/CCUS-like state.
MDS/leukemia is a huge problem-but this state is also clinically relevant. You have a patient with severe thrombocytopenia which limits the ability to use subsequent therapies.
Many studies have reported on t-MN, but future studies should also look at these earlier clonal cytopenia states as an endpoint that is clinically relevant, as such patients can transform as well.
In addition, we are in a dire need to know who these patients are who are prone to develop cytopenia. Our group and others have shown how an underlying mutation in hematopoietic stem cells (clonal hematopoiesis; CH) increases risk of thrombocytopenia after PRRT. Longer follow up is needed.
Can CH be a tool in the clinic to help us sit down with a patient with NET and say: given you have CH, then likely better to go with drug X (cabo, everolimus, etc.) instead of PRRT for now? Can that help with sequencing?
In addition, we need to know for those who have CH at baseline and will get PRRT-how can we mitigate this risk? Can we give something to decrease that risk?
All these are questions that are worth asking and investigating.”
Quoting Thor Halfdanarson‘s post:
More on treatment related myeloid neoplasms (t-MN) following radioligand therapy (PRRT) in patients with NETs.
4.2% of patients develop t-MN after a median time of 48.3 months. Nine of 13 patients with t-MN received radiosensitizing chemotherapy, almost exclusively capecitabine (not standard practice in the U.S. ).
As expected, survival after t-MN and diagnosis was short. 10.4 months.
This is a very valuable addition to the literature from David Chan and team!”
Title: Therapy-related myeloid neoplasms following peptide receptor radionuclide therapy for neuroendocrine neoplasms: case series reporting characteristics and outcomes from single-centre experience
Authors: Wallace Chow, Ivy Wen, Claire Mok, Kathryn Huang, William Stevenson, Paul J Roach, Dale L Bailey, Connie I Diakos, Stephen J Clarke, Nick Pavlakis, David L Chan
Read The Full Article
Other articles about PRRT on OncoDaily.