Peptide Radiation Therapy Triggered a Dangerous Cortisol Surge in a Cushing Syndrome Patient

A patient with ectopic Cushing syndrome from a thymic neuroendocrine tumor experienced a life-threatening cortisol crisis 5 days after starting PRRT, requiring emergency intervention.

Pandit, Raghavendra et al.·JCEM case reports·2025·very-lowCase Report
RPEP-12937Case Reportvery-low2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Case Report
Evidence
very-low
Sample
N=1
Participants
One adult woman with metastatic ectopic Cushing syndrome from a thymic neuroendocrine tumor

What This Study Found

PRRT triggered an acute ACTH-mediated hypercortisolemic crisis in a patient with ectopic Cushing syndrome, with cortisol reaching 141 µg/dL (normal: 5-25 µg/dL) and ACTH >2000 pg/mL, requiring emergency management.

Key Numbers

Cortisol peaked at 141 mcg/dL (reference: 5-25). ACTH exceeded 2,000 pg/mL (reference: 10-60). Patient gained 8 kg in one week. Etomidate dose: 0.02 mg/kg/h IV. Crisis occurred 5 days after first PRRT cycle.

How They Did This

Case report documenting clinical presentation, biochemical findings, imaging, and management of PRRT-induced hypercortisolemic crisis.

Why This Research Matters

PRRT is increasingly used for neuroendocrine tumors, but this case demonstrates that tumor lysis or stimulation during treatment can trigger dangerous hormone surges. Clinicians need to anticipate and prepare for this complication, especially in functioning tumors.

The Bigger Picture

As PRRT use expands beyond the traditional GEP-NET setting, clinicians will encounter more patients with functioning tumors. This case is an important addition to the safety literature and may influence pre-treatment evaluation protocols for PRRT candidates.

What This Study Doesn't Tell Us

Single case report — cannot establish incidence or risk factors; the mechanism (tumor lysis vs. radiation-induced hormone release) is speculative; management details may not be generalizable.

Questions This Raises

  • ?Should patients with functioning neuroendocrine tumors receive prophylactic cortisol-blocking therapy before PRRT?
  • ?Is this complication predictable based on pre-treatment ACTH levels or tumor burden?
  • ?Should PRRT protocols include hormone monitoring protocols for the first week after treatment?

Trust & Context

Key Stat:
Cortisol 141 µg/dL Nearly 6x the upper normal limit, triggered 5 days after first PRRT dose in a Cushing syndrome patient
Evidence Grade:
Single case report — lowest level of evidence but important for documenting rare adverse events and guiding safety protocols.
Study Age:
Published in 2025, timely given the expanding use of PRRT for neuroendocrine tumors.
Original Title:
Peptide Receptor Radionuclide Therapy-Induced Hypercortisolemic Crisis in Ectopic Cushing Syndrome.
Published In:
JCEM case reports, 3(11), luaf226 (2025)
Database ID:
RPEP-12937

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Describes what happened to one person or a small group.

What do these levels mean? →

Frequently Asked Questions

What is peptide receptor radionuclide therapy (PRRT)?

PRRT uses radioactive atoms attached to small peptides that seek out and bind to receptors on neuroendocrine tumor cells. The radiation then destroys the tumor cells from the inside. It's an effective treatment but can sometimes cause tumors to release their contents, including hormones.

Why did the treatment cause a cortisol crisis?

The patient's tumor was producing excess ACTH, which drives cortisol production. When PRRT started destroying tumor cells, it may have triggered a massive release of stored ACTH, causing cortisol levels to spike dangerously — similar to a dam breaking.

Read More on RethinkPeptides

Cite This Study

RPEP-12937·https://rethinkpeptides.com/research/RPEP-12937

APA

Pandit, Raghavendra; Yamichannaiah, Chethan; Lila, Anurag Ranjan; Karlekar, Manjiri; Memon, Saba Samad; Bandgar, Tushar. (2025). Peptide Receptor Radionuclide Therapy-Induced Hypercortisolemic Crisis in Ectopic Cushing Syndrome.. JCEM case reports, 3(11), luaf226. https://doi.org/10.1210/jcemcr/luaf226

MLA

Pandit, Raghavendra, et al. "Peptide Receptor Radionuclide Therapy-Induced Hypercortisolemic Crisis in Ectopic Cushing Syndrome.." JCEM case reports, 2025. https://doi.org/10.1210/jcemcr/luaf226

RethinkPeptides

RethinkPeptides Research Database. "Peptide Receptor Radionuclide Therapy-Induced Hypercortisole..." RPEP-12937. Retrieved from https://rethinkpeptides.com/research/pandit-2025-peptide-receptor-radionuclide-therapyinduced

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.