Dataset Information

A pilot study of ⁶⁸ Ga-PSMA-617 PET/CT imaging and ¹⁷⁷Lu-EB-PSMA-617 radioligand therapy in patients with adenoid cystic carcinoma.

ABSTRACT:

Background

This pilot study was designed to evaluate the diagnostic value of ⁶⁸ Ga-PSMA-617 and ¹⁸F-FDG PET/CT in adenoid cystic carcinoma (ACC) and to assess the safety and therapeutic response to PSMA radioligand therapy (RLT) in ACC patients.

Methods

Thirty patients pathologically diagnosed with ACC were recruited into the cohort. Each patient underwent ⁶⁸ Ga-PSMA-617 and ¹⁸F-FDG PET/CT within 1 week. The number and SUVmax of PET-positive lesions were recorded and compared. Four patients accepted RLT using ¹⁷⁷Lu-EB-PSMA-617, in a dosage of approximately 1.85 GBq (50 mCi) per cycle for up to 3 cycles.

Results

Compared with ¹⁸F-FDG, ⁶⁸ Ga-PSMA-617 revealed more PET-positive extrapulmonary tumors (157 vs. 141, P = 0.016) and higher SUVmax (8.8 ± 3.6 vs. 6.4 ± 4.2, P = 0.027). However, ⁶⁸ Ga-PSMA-617 revealed less PET-positive pulmonary lesions (202 vs. 301, P < 0.001) and lower SUVmax of tumors (3.1 ± 3.0 vs. 4.2 ± 3.9, P < 0.001) than ¹⁸F-FDG. The combination of ⁶⁸ Ga-PSMA-617 and ¹⁸F-FDG can detect 469 PET-positive lesions, which was superior to each alone (469 vs. 359 vs. 442, P < 0.001). Two patients achieved remarkable response after PSMA RLT, while the other two patients showed reduced tumor uptake of recurrent foci, lung and liver metastases, whereas increased SUVmax of bone metastases.

Conclusions

⁶⁸ Ga-PSMA-617 PET/CT is a valuable imaging modality for the detection of ACC and combining with ¹⁸F-FDG PET/CT will achieve a higher detection efficiency. PSMA RLT may be a promising treatment for ACC and is worth of further investigation.

Trial registration

Diagnosis of Adenoid Cystic Carcinoma on ⁶⁸ Ga-PSMA-617 PET-CT and Therapy With ¹⁷⁷Lu-EB-PSMA-617 (NCT04801264, Registered 16 March 2021, retrospectively registered). URL of registry: https://clinicaltrials.gov/ct2/show/NCT04801264 .

SUBMITTER: Wang G

PROVIDER: S-EPMC9390098 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Publications

A pilot study of <sup>68</sup> Ga-PSMA-617 PET/CT imaging and <sup>177</sup>Lu-EB-PSMA-617 radioligand therapy in patients with adenoid cystic carcinoma.

Wang Guochang G Zhou Mengjiao M Zang Jie J Jiang Yuanyuan Y Chen Xiaohong X Zhu Zhaohui Z Chen Xiaoyuan X

EJNMMI research 20220819 1

<h4>Background</h4>This pilot study was designed to evaluate the diagnostic value of <sup>68</sup> Ga-PSMA-617 and <sup>18</sup>F-FDG PET/CT in adenoid cystic carcinoma (ACC) and to assess the safety and therapeutic response to PSMA radioligand therapy (RLT) in ACC patients.<h4>Methods</h4>Thirty patients pathologically diagnosed with ACC were recruited into the cohort. Each patient underwent <sup>68</sup> Ga-PSMA-617 and <sup>18</sup>F-FDG PET/CT within 1 week. The number and SUVmax of PET-posi ...[more]

PMID: 35984529

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Project description:Baseline uptake on prostate-specific membrane antigen (PSMA)-targeted imaging is a prerequisite for radioligand therapy (RLT) with [177Lu]Lu-PSMA-617. This study aims to quantify lesion-based response to RLT in relation to pretreatment standard molecular imaging metrics derived from [68Ga]Ga-PSMA-11 PET/CT. Sixty-one patients with mCRPC underwent [68Ga]Ga-PSMA-11 PET/CT imaging before and after a median of 4 (IQR 2-6) RLT cycles. Maximum and mean standardized uptake values (SUVmax, SUVmean), as well as tumor-to-liver ratio (TLR), were assessed. A median of 12 (IQR 7-17) lesions was analyzed per patient, resulting in a total of 718 lesions. Lesions with ≥30% SUVmax decline or falling below the blood pool uptake were considered responsive; ≥30% SUVmax increase marked lesion progression. Additionally, 4-point visual scoring was performed according to E-PSMA consensus. In total, 550/718 (76.6%) lesions responded to RLT, including 389/507 (76.7%) bone metastases and 143/181 (79.0%) lymph node metastases. Baseline SUVmax, SUVmean, and TLR values were associated with lesion response by a moderate but significant correlation (rs = 0.33, p < 0.001, rs = 0.32, p < 0.001, and rs = 0.31, p < 0.001, respectively). For the classification of lesion progression based on baseline PSMA uptake, receiver operating characteristics (ROC) found SUVmax, SUVmean, and TLR to have comparable discriminatory value (AUC 0.85, 0.87, and 0.83). Of 42 tumor sites with baseline uptake below the liver (V-score < 2), 19/42 (45.2%) were responsive, 9/42 (21.4%) were stable, and 14/42 (33.3%) showed progression, leaving liver uptake a threshold with low prognostic value for the identification of RLT-refractory lesions (PPV 33%). This was observed accordingly for various liver uptake-based thresholds, including TLR < 1.5, <2.0 with a PPV at 24%, 20%, respectively. Standard uptake parameters quantified by routine baseline [68Ga]Ga-PSMA-11 PET/CT are moderately associated with post-treatment lesion response to [177Lu]Lu-PSMA-617. Commonly applied liver-based uptake thresholds have limited value in predicting refractory lesions at individual tumor sites.

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Project description:PurposeThe first aim of this study was to evaluate 68Ga-PSMAHBED-CC conjugate 11 positron emission tomography (PSMA PET) parameters for assessment of response to 177Lu-PSMA-617 radioligand therapy (RLT) in patients with metastatic castration-resistant prostate cancer (mCRPC). The second aim was to investigate factors associated with overall survival (OS).MethodsWe retrospectively assessed mean standardized uptake values (SUVmean) and total tumor volumes (TTV) on PSMA PET in 38 of 55 mCRPC patients before and after RLT. PSA testing and PSMA PET/CT(MRI) imaging were performed during the 8 weeks before and the 6 weeks after RLT. PSMA PET and CT(MRI) images were reviewed separately according to the modified PET Response Criteria in Solid Tumors (mPERCIST) and RECIST1.1. The results were compared with PSA responses. Associations between OS and the RECIST evaluation and changes in SUVmean, TTV, and PSA, CRP, LDH, hemoglobin and ALP levels were determined in a univariable survival analysis.ResultsThe median PSA level at the time of pretherapy PSMA PET/CT(MRI) was 60.8 ng/ml (IQR 15.4, 264.2 ng/ml). After RLT the median PSA level decreased by 44%, TTV by 45.1%, SUVmean by 25.8% and RECIST by 11.3%. A PSA response was seen in 18 patients (47.4%), stable disease in 12 (31.6%) and progressive disease in 8 (21.1%). Contrary to the changes in SUVmean and the RECIST evaluation, the change in TTV was significantly associated with PSA response (p = 0.15, p = 0.58, and p < 0.001, respectively). After a median follow-up of 17 months (IQR 8.0, 24.2 months), 11 patients (28.9%) had died of their prostate cancer. The changes in both TTV and PSA levels were associated with OS (HR 1.001, 95% CI 1-1.003, p = 0.04, and HR 1.004, 95% CI 1.001-1.008, p = 0.01, respectively), while the changes in SUVmean and the RECIST evaluation were not. The pre-therapy CRP level was also associated with OS (HR 1.07, 95% CI 1.009-1.14, p = 0.02).ConclusionTTV on PSMA PET seems to be a reliable parameter for response assessment in mCRPC patients undergoing RLT and might overcome the limitations of RECIST in prostate cancer. Furthermore, the change in TTV was significantly associated with OS in our cohort.

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Dataset Information

A pilot study of ⁶⁸ Ga-PSMA-617 PET/CT imaging and ¹⁷⁷Lu-EB-PSMA-617 radioligand therapy in patients with adenoid cystic carcinoma.

Background

Methods

Results

Conclusions

Trial registration

Publications

A pilot study of <sup>68</sup> Ga-PSMA-617 PET/CT imaging and <sup>177</sup>Lu-EB-PSMA-617 radioligand therapy in patients with adenoid cystic carcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

A pilot study of 68 Ga-PSMA-617 PET/CT imaging and 177Lu-EB-PSMA-617 radioligand therapy in patients with adenoid cystic carcinoma.

Background

Methods

Results

Conclusions

Trial registration

Publications

A pilot study of <sup>68</sup> Ga-PSMA-617 PET/CT imaging and <sup>177</sup>Lu-EB-PSMA-617 radioligand therapy in patients with adenoid cystic carcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

A pilot study of ⁶⁸ Ga-PSMA-617 PET/CT imaging and ¹⁷⁷Lu-EB-PSMA-617 radioligand therapy in patients with adenoid cystic carcinoma.