Diagnostic Value of CXCR4-targeted PET/CT in ACTH-dependent and Independent Cushing's Syndrome

Phase 2RecruitingNCT07350707

Peking Union Medical College Hospital160 enrolled

Overview

In previous clinical practice, 68Ga-Pentixafor PET/CT has demonstrated promising diagnostic utility in various neuroendocrine tumors by targeting CXCR4, a chemokine receptor overexpressed in several ACTH-secreting neoplasms. Building on this, and leveraging the Nuclear Medicine expertise at Peking Union Medical College Hospital, we aim to conduct a prospective observational study investigating the role of CXCR4-targeted PET/CT imaging in patients with confirmed or suspected Cushing's syndrome. This study will focus on evaluating the capability of \^68Ga-Pentixafor PET/CT to assist in the differential diagnosis of ACTH-dependent and ACTH-independent subtypes, as well as in the localization of primary lesions in challenging cases. Imaging performance will be assessed in comparison with conventional modalities and/or 68Ga-DOTATATE PET/CT when available.

Study Type

INTERVENTIONAL

Allocation

Purpose

DIAGNOSTIC

Masking

NONE

Enrollment

160

Conditions

Cushing s Syndrome

Interventions

All enrolled participants will undergo \^68Ga-Pentixafor PET/CT to evaluate CXCR4 expression patterns and assist in the differential diagnosis of ACTH-dependent and ACTH-independent subtypes. In cases where ectopic ACTH syndrome (EAS) is clinically suspected-such as in patients with inconclusive pituitary imaging or discordant biochemical profiles-an additional \^68Ga-DOTATATE PET/CT scan will be performed as part of the diagnostic workup. This allows for a head-to-head comparison between CXCR4-targeted and somatostatin receptor (SSTR)-targeted imaging modalities in the localization of ACTH-secreting tumors.

Eligibility

Sex: ALLMin age: 10 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Clinical suspicion or confirmed diagnosis of Cushing's syndrome, based on clinical features (e.g., central obesity, moon face, muscle weakness) and/or abnormal cortisol-related biochemical tests. * Able and willing to undergo PET/CT imaging with both 68Ga-Pentixafor and, when applicable, 68Ga-DOTATATE. * Willing to provide informed consent for participation in the study. Exclusion Criteria: * Prior administration of therapeutic or investigational radiopharmaceuticals within 5 physical half-lives before study imaging. Pregnancy or breastfeeding. * History of allergic reaction to gallium-based tracers or related compounds. * Clinically unstable condition or severe organ dysfunction that, in the investigator's opinion, would interfere with PET/CT imaging or study participation. * Inability to complete both 68Ga-Pentixafor and, when applicable, 68Ga-DOTATATE PET/CT imaging due to clinical or logistical reasons.

Outcomes

Primary Outcomes

Diagnostic value

Sensitivity and Specificity of 68Ga-Pentxiafor PET/CT for Cushing's Syndrome

Time frame: From baseline PET/CT assessment to end of study (approximately 12 months)