TY  - JOUR
A1  - Lapa, Constantin
A1  - Schreder, Martin
A1  - Schirbel, Andreas
A1  - Samnick, Samuel
A1  - Kortüm, Klaus Martin
A1  - Herrmann, Ken
A1  - Kropf, Saskia
A1  - Einsele, Herrmann
A1  - Buck, Andreas K.
A1  - Wester, Hans-Jürgen
A1  - Knop, Stefan
A1  - Lückerath, Katharina
T1  - [\(^{68}\)Ga]Pentixafor-PET/CT for imaging of chemokine receptor CXCR4 expression in multiple myeloma - comparison to [\(^{18}\)F]FDG and laboratory values
JF  - Theranostics
N2  - Chemokine (C-X-C motif) receptor 4 (CXCR4) is a key factor for tumor growth and metastasis in several types of human cancer including multiple myeloma (MM). Proof-of-concept of CXCR4-directed radionuclide therapy in MM has recently been reported. This study assessed the diagnostic performance of the CXCR4-directed radiotracer [\(^{68}\)Ga]Pentixafor in MM and a potential role for stratifying patients to CXCR4-directed therapies.

Thirty-five patients with MM underwent [\(^{68}\)Ga]Pentixafor-PET/CT for evaluation of eligibility for endoradiotherapy. In 19/35 cases, [\(^{18}\)F]FDG-PET/CT for correlation was available. Scans were compared on a patient and on a lesion basis. Tracer uptake was correlated with standard clinical parameters of disease activity.

[\(^{68}\)Ga]Pentixafor-PET detected CXCR4-positive disease in 23/35 subjects (66%). CXCR4-positivity at PET was independent from myeloma subtypes, cytogenetics or any serological parameters and turned out as a negative prognostic factor. In the 19 patients in whom a comparison to [\(^{18}\)F]FDG was available, [\(^{68}\)Ga]Pentixafor-PET detected more lesions in 4/19 (21%) subjects, [\(^{18}\)F]FDG proved superior in 7/19 (37%). In the remaining 8/19 (42%) patients, both tracers detected an equal number of lesions. [\(^{18}\)F]FDG-PET positivity correlated with [\(^{68}\)Ga]Pentixafor-PET positivity (p=0.018).

[\(^{68}\)Ga]Pentixafor-PET provides further evidence that CXCR4 expression frequently occurs in advanced multiple myeloma, representing a negative prognostic factor and a potential target for myeloma specific treatment. However, selecting patients for CXCR4 directed therapies and prognostic stratification seem to be more relevant clinical applications for this novel imaging modality, rather than diagnostic imaging of myeloma.
KW  - medicine
KW  - multiple myeloma
KW  - FDG
KW  - molecular imaging
KW  - CXCR4
KW  - PET
KW  - radionuclide therapy
KW  - theranostics
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172106
VL  - 7
IS  - 1
ER  - 
TY  - JOUR
A1  - Lapa, Constantin
A1  - Kircher, Malte
A1  - Hänscheid, Heribert
A1  - Schirbel, Andreas
A1  - Grigoleit, Götz Ulrich
A1  - Klinker, Erdwine
A1  - Böck, Markus
A1  - Samnick, Samuel
A1  - Pelzer, Theo
A1  - Buck, Andreas K
T1  - Peptide receptor radionuclide therapy as a new tool in treatment-refractory sarcoidosis - initial experience in two patients
JF  - Theranostics
N2  - Sarcoidosis is a multisystem granulomatous disorder of unknown etiology that can involve virtually all organ systems. Whereas most patients present without symptoms, progressive and disabling organ failure can occur in up to 10% of subjects. Somatostatin receptor (SSTR)-directed peptide receptor radionuclide therapy (PRRT) has recently received market authorization for treatment of SSTR-positive neuroendocrine tumors.

Methods: 
We describe the first case series comprising two patients with refractory multi-organ involvement of sarcoidosis who received 4 cycles of PRRT.

Results: 
PRRT was well-tolerated without any acute adverse effects. No relevant toxicities could be recorded during follow-up. Therapy resulted in partial response accompanied by a pronounced reduction in pain (patient #1) and stable disease regarding morphology as well as disease activity (patient #2), respectively.

Conclusion: 
Peptide receptor radionuclide therapy in sarcoidosis is feasible and might be a new valuable tool in patients with otherwise treatment-refractory disease. Given the long experience with and good tolerability of PRRT, further evaluation of this new treatment option for otherwise treatment-refractory sarcoidosis in larger patient cohorts is warranted.
KW  - peptide receptor
KW  - PRRT
KW  - sarcoidosis
KW  - somatostatin receptors
KW  - radionuclide therapy
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158983
VL  - 8
IS  - 3
ER  -