The role of 18F-FAZA PET/CT in detecting lymph node metastases in renal cell carcinoma patients: a prospective pilot trial

• Published in: European journal of nuclear medicine and molecular imaging 2021-02, Vol.48 (2), p.554-560
• Main Authors: Capitanio, Umberto, Pepe, Gino, Incerti, Elena, Larcher, Alessandro, Trevisani, Francesco, Lucianò, Roberta, Mapelli, Paola, Bettinardi, Valentino, Monterisi, Cristina, Necchi, Andrea, Cascinu, Stefano, Bernardi, Rosa, Bertini, Roberto, Doglioni, Claudio, Gianolli, Luigi, Salonia, Andrea, Picchio, Maria, Montorsi, Francesco
• Format: Article
• Language: English
• Subjects: Adverse events; Cancer; Cardiology; Computed tomography; Diagnostic systems; Fluorine isotopes; Hypoxia; Imaging; Intravenous administration; Kidney cancer; Lymph nodes; Lymphatic system; Medical imaging; Medicine; Medicine & Public Health; Metastases; Metastasis; Nuclear Medicine; Oncology; Oncology – Genitourinary; Original Article; Orthopedics; Patients; Positron emission; Positron emission tomography; Qualitative analysis; Radioactive tracers; Radiology; Renal cell carcinoma; Surgery; Tomography; Tumors
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-020-04936-2

Background The accurate detection of nodal invasion is an unmet need in the clinical staging of renal cancer. Positron emission tomography (PET) with 18F-fluoroazomycin arabinoside (18F-FAZA), a hypoxia specific tracer, is a non-invasive imaging method that detects tumour hypoxia. The aim of this work was to evaluate the role of 18F-FAZA PET/CT in the identification of lymph node metastases in renal cancer. Methods A proof-of-concept phase 2 study including 20 kidney cancer patients ( ClinicalTrials.gov Identifier: NCT03955393) was conducted. Inclusion criteria were one or more of the following three criteria: (1) clinical tumour size > 10 cm, (2) evidence of clinical lymphadenopathies at preoperative CT scan and (3) clinical T4 cancer. Before surgery, 18F-FAZA PET/CT was performed, 2 h after the intravenous injection of the radiotracer. An experienced nuclear medicine physician, aware of patient’s history and of all available diagnostic imaging, performed a qualitative and semi-quantitative analysis on 18F-FAZA images. Histopathological analysis was obtained in all patients on surgical specimen. Results Fourteen/19 (74%) patients had a non-organ confined renal cell carcinoma (RCC) at final pathology (either pT3 or pT4). Median number of nodes removed was 12 (IQR 7–15). The rate of lymph node invasion was 16%. No patient with pN1 disease showed positive 18F-FAZA PET, thus suggesting the non-hypoxic behaviour of the lesions. In addition, neither primary tumour nor distant metastases presented a pathological 18F-FAZA uptake. No adverse events were recorded during the study. Conclusions 18F-FAZA PET/CT scan did not detect RCC lymph neither nodal nor distant metastases and did not show any uptake in the primary renal tumour.