We analyzed the diagnostic performance of prostate-specific membrane antigen (PSMA) PET/CT and the dosimetry, efficacy, and safety of ¹⁷⁷Lu-PSMA-617 radioligand therapy (RLT) in salivary gland malignancies (SGMs). Methods: We identified 28 SGM patients with PSMA PET/CT from our database. CT and PSMA PET/CT images were evaluated separately by 3 masked readers in joint reading sessions. Pathologic findings were grouped into 6 TNM regions, and lesion-based disease extent was classified as no disease (n = 1, 4%), unifocal (n = 2, 7%), oligometastatic (n = 9, 32%), multifocal (n = 3, 11%), or disseminated (n = 13, 47%). For each region, the SUV_max of the lesion with the highest uptake was measured and the visual PSMA expression score was evaluated on a per-patient basis using PROMISE criteria. The association between PSMA expression and clinical and histopathologic markers was tested using the Student t test. Five patients underwent PSMA RLT with intratherapeutic dosimetry. Response was assessed using RECIST 1.1, and adverse events were graded according to version 5.0 of the Common Terminology Criteria for Adverse Events. Results: Compared with CT, PSMA PET/CT demonstrated additional metastatic lesions in 11 of 28 (39%) patients, leading to upstaging of TNM and lesion-based disease extent in 3 (11%) and 6 (21%) patients, respectively. PSMA PET/CT detected CT-occult local tumor, regional lymph nodes, nonregional lymph nodes, and bone metastases in 1 (4%), 4 (14%), 2 (7%), and 4 (14%) patients, respectively; no additional lesions were detected in the other predefined regions. PSMA expression level was higher than liver in 6 patients (25%). A significantly higher SUV_max was observed in male than female patients (15.8 vs. 8.5, P = 0.007) and in bone than lung lesions (14.2 vs. 6.4, P = 0.006). PSMA RLT was discontinued after 1 cycle in 3 of 5 patients because of insufficient tumor doses. No adverse events of grade 4 or higher occurred. Conclusion: In SGMs, PSMA PET/CT demonstrated a superior detection rate and led to upstaging in about one third of patients when compared with CT. The male sex and the presence of bone metastases were associated with significantly higher PSMA expression. PSMA RLT was well tolerated, but most patients did not have more than 1 cycle because of insufficient tumor doses.

^{我们分析了前列腺特异性膜抗原 (PSMA) PET/CT 的诊断性能以及177} Lu-PSMA-617 放射配体疗法 (RLT) 在唾液腺恶性肿瘤 (SGM) 中的剂量测定、疗效和安全性。方法：我们从数据库中确定了 28 名接受 PSMA PET/CT 的 SGM 患者。CT 和 PSMA PET/CT 图像由 3 名蒙面读者在联合阅读会议中分别评估。病理结果分为 6 个 TNM 区域，基于病变的疾病范围分为无疾病 ( n  = 1, 4%)、单灶性 ( n  = 2, 7%)、寡转移性 ( n  = 9, 32%)、多灶性( n  = 3, 11%)，或传播 ( n  = 13, 47%)。对于每个区域，测量具有最高摄取的病变的SUV _{max ，并使用 PROMISE 标准对每个患者的视觉 PSMA 表达评分进行评估。}使用 Student t检验测试 PSMA 表达与临床和组织病理学标志物之间的关联。5 名患者接受了 PSMA RLT 治疗内剂量测定。使用 RECIST 1.1 评估疗效，并根据不良事件通用术语标准 5.0 版对不良事件进行分级。结果：与 CT 相比，PSMA PET/CT 在 28 名患者中的 11 名 (39%) 中显示出额外的转移病灶，分别导致 3 名 (11%) 和 6 名 (21%) 名患者的 TNM 分期和基于病变的疾病范围上调。PSMA PET/CT 分别在 1 例 (4%)、4 例 (14%)、2 例 (7%) 和 4 例 (14%) 患者中检测到 CT 隐匿性局部肿瘤、区域淋巴结、非区域淋巴结和骨转移; 在其他预定区域中没有检测到额外的病变。6 名患者 (25%) 的 PSMA 表达水平高于肝脏。_{男性患者的 SUV max}显着高于女性患者（15.8 vs. 8.5， P  = 0.007），骨骼病变的 SUV max 显着高于肺部病变（14.2 vs. 6.4，P  = 0.006）。由于肿瘤剂量不足，5 名患者中有 3 名在 1 个周期后停止 PSMA RLT。未发生4级或以上不良事件。结论：在 SGM 中，与 CT 相比，PSMA PET/CT 显示出更高的检出率，并导致约三分之一的患者升期。男性和骨转移的存在与显着较高的 PSMA 表达相关。PSMA RLT 耐受性良好，但由于肿瘤剂量不足，大多数患者的治疗周期不超过 1 个周期。