Stable metastatic NET – should I be pushing harder for PRRT?

Posted by donbarks @donbarks, Feb 3 7:01am

Hi everyone,
I’m hoping to get some perspectives from others who have faced similar decisions around PRRT.

I’m a 40-year-old male with a well-differentiated Grade 2 neuroendocrine tumour, originally diagnosed in 2020. Primary tumour (upper bowel) was surgically resected at diagnosis (initially staged T4N1M0).

In 2023, follow-up imaging identified multiple small liver metastases. These were treated with radiofrequency / microwave ablation, with good response. Since then, imaging has shown small-volume residual liver disease, all lesions currently ≤ ~11 mm, with no extrahepatic spread.

Recent imaging (MRI and PET-CT) shows:
- Disease is radiologically stable overall
- One lesion has shown very slow growth over time
- No new liver lesions
- No disease outside the liver
- Ongoing somatostatin receptor positivity

I’m currently on long-acting somatostatin therapy and otherwise clinically well. Blood markers are generally stable.

My oncologist and interventional radiologist feel that:
- Lesions are currently too small to justify further ablation
- PRRT is not recommended yet given stability and low tumour burden
- Plan is continued surveillance, with reassessment if progression becomes clearer

I understand the reasoning, but I’m also conscious that PRRT is often described as most effective before tumour burden becomes larger, and I want to make sure I’m not missing an opportunity by waiting too long.

So my questions to the group:
- For those who have had PRRT: what triggered the decision to proceed?
- Did anyone pursue PRRT while disease was technically “stable” but slowly progressing?
- Are there downsides to waiting until clearer progression versus treating earlier?

If you were in my situation, would you push harder for PRRT now or stay the course? I have a good relationship with my care team and don’t want to be reckless — just trying to be proactive and well-informed.

Thanks in advance for any insights or experiences you’re willing to share.

Interested in more discussions like this? Go to the Neuroendocrine Tumors (NETs) Support Group.

grange | @grange | Feb 5 8:52am

In reply to @dbamos1945 "@grange: Regarding your wife’s Lingering side-effects from Lutathera PRRT… I can tell you my response in..." + (show)

@dbamos1945 Thank you for responding. ‘Congratulations on your PRRT results. That’s fantastic. My wife gets her first post PRRT scan tomorrow and we’ll get results next week. I will pass along your advice to her. She for sure needs to drink more water and I’ll help her eat more small meals more often. We are avoiding rich foods. She doesn’t have much of an appetite and nothing sounds good to her. Can you tell me what kind of small meals you eat. I’m having a hard time figuring out what to cook for her.
Thank you again for your response.

tfoucaul | @tfoucaul | Feb 5 11:05am

In reply to @tomrennie "@tfoucaul Sounds like you might have some experience with PRRT? If so, can you please share?..." + (show)

Well, next week, I'll be getting my 4th and final lutathera-prrt retreatment. I'm also combining Keytruda as well. I had my initial 4 treatments back in 2023 I think. Generally, I take some anti- nausea meds for about 10 days after to ensure no nausea. I also drink lots of coffee/water/fluids after prrt as well since I don't want to kill my kidneys. I believe the major risks of lutathera are mylosuppression and or leukemia. These usually present themselves about 2 years after treatment. I'm not sure what the increased risks for the retreatments are since the RETREAT study ain't done. Wait and see, I guess. It's criminal that this treatment costs $750k in us but only $55k euros in europe.

donbarks | @donbarks | Feb 6 6:36am

In reply to @hopeful33250 "Hello @donbarks and welcome to the NETs support group on Mayo Connect. I'm glad to see..." + (show)

@hopeful33250 Thank you for the welcome. Really feels good to have a community to chat to about this!

No, I feel perfect. I guess the odd digestive issue, but nothing to complain about. I'm trying to eat healthy, exercise and keep positive.

I live in South Africa and haven't found an NET specialist however my oncologist does have a few patients with NET's. I have bloods and see my oncologist every 4 weeks when I go for my Sandostatin injection. I also see my interventional radiologist every 3 months for an ultrasound then get a PET scan and MRI scan once a year usually 6 months apart.

Based on the feedback I've seen on this post, it does seem that PRRT is a solution I should review only later in my journey. My mind is a little more at ease!

vinnie694 | @vinnie694 | Feb 6 8:26am

In reply to @donbarks "@hopeful33250 Thank you for the welcome. Really feels good to have a community to chat to..." + (show)

@donbarks Best wishes and hope for a great outcome!

markmark007 | @markmark007 | Feb 6 8:54am

Based on the experience of my wife's NET journey since 2014 , I echo what many have said in another way:
"Keep the powder dry"

Turkey, Volunteer Mentor | @tomrennie | Feb 6 10:22am

In reply to @markmark007 "Based on the experience of my wife's NET journey since 2014 , I echo what many..." + (show)

@markmark007 I have never heard of that saying before. But now that I have looked it up and know what it means, "remain cautious and ready for a possible emergency", it is so true. Thanks for sharing.

Turkey, Volunteer Mentor | @tomrennie | Feb 6 10:35am

In reply to @tfoucaul "Well, next week, I'll be getting my 4th and final lutathera-prrt retreatment. I'm also combining Keytruda..." + (show)

@tfoucaul I did learn yesterday on the NETs support group zoom call that myelosuppression and leukemia are the major risks of PRRT from Mayo's Net Oncologist Thor Halfdanarson. He agreed that they usually present themselves in about 2 years after treatment. He also suggested that there isn't enough historical data to be more specific than that. Please keep us updated PRRT recipients. We are learning through your experience. Thank you.