PT  - JOURNAL ARTICLE
AU  - Walter Rachinger
AU  - Veit M. Stoecklein
AU  - Nicole A. Terpolilli
AU  - Alexander R. Haug
AU  - Lorenz Ertl
AU  - Julia Pöschl
AU  - Ulrich Schüller
AU  - Christian Schichor
AU  - Niklas Thon
AU  - Jörg-Christian Tonn
TI  - Increased <sup>68</sup>Ga-DOTATATE Uptake in PET Imaging Discriminates Meningioma and Tumor-Free Tissue
AID  - 10.2967/jnumed.114.149120
DP  - 2015 Mar 01
TA  - Journal of Nuclear Medicine
PG  - 347--353
VI  - 56
IP  - 3
4099  - http://jnm.snmjournals.org/content/56/3/347.short
4100  - http://jnm.snmjournals.org/content/56/3/347.full
SO  - J Nucl Med2015 Mar 01; 56
AB  - Meningiomas are known to express somatostatin receptor 2 (SSTR2). PET using the SSTR2 analog 68Ga-DOTATATE has recently been introduced for imaging of meningiomas. However, a systematic correlation between 68Ga-DOTATATE uptake, SSTR2 expression, and histology (including tumor-free scar tissue) is still lacking. For elucidation, we conducted this prospective study. Methods: Twenty-one adult patients with primary (n = 12) or recurrent (n = 9) meningiomas were prospectively enrolled. Preoperative MR imaging and 68Ga-DOTATATE PET scans were fused and used for a spatially precise neuronavigated tissue-sampling procedure during tumor resection. Histopathologic diagnosis included immunohistochemical determination of SSTR2 expression. At each individual sampling site, the maximum standardized uptake value (SUVmax) of 68Ga-DOTATATE was correlated with MR imaging findings, histology, and semiquantitative SSTR2 expression. Results: One hundred fifteen samples (81 tumor, 34 tumor-free) were obtained. There was a significant positive correlation between SUVmax and SSTR2 expression. Receiver-operating characteristic analysis revealed a threshold of 2.3 for SUVmax to discriminate between tumor and nontumoral tissue. Regarding the detection of tumor tissue, PET imaging showed a higher sensitivity (90% vs. 79%; P = 0.049), with specificity and positive predictive values similar to MR imaging, for both de novo and recurrent tumors. Conclusion: 68Ga-DOTATATE uptake correlates with SSTR2 expression and offers high diagnostic accuracy to delineate meningioma from tumor-free tissue even in recurrent tumors after previous therapy. Our findings substantiate an important role for 68Ga-DOTATATE PET in meningioma management.