Diagnostic value of neck node status using 18F-FDG PET for salivary duct carcinoma of the major salivary glands.
ABSTRACT (18)F-FDG PET and PET/CT have shown clinical usefulness in the initial staging and follow-up of patients with salivary malignancy. Therefore, we evaluated the utility of (18)F-FDG PET in preoperative staging, determining the extent of neck node involvement, and surgical planning for patients with salivary duct carcinoma (SDC) of the major salivary gland.
We evaluated 18 patients with SDC who were assessed by (18)F-FDG PET and CT before surgery. The sensitivity, specificity, accuracy, and predictive values of CT and PET/CT for predicting the primary tumor site and determining the extent of neck node involvement at each dissected neck level were evaluated by comparing imaging findings with pathologic nodal stage.
The median maximum standardized uptake value of the primary lesions and cervical nodes were 4.7 (range, 1.8-12.1) and 5.8 (range, 1.7-13.0), respectively. The sensitivities of (18)F-FDG PET and CT for predicting the primary tumor site were 100% (18/18) and 94.4% (17/18), respectively. In analyzing cervical lymph nodes at 73 dissected neck levels, (18)F-FDG PET had a sensitivity of 76.1%, a specificity of 96.3%, a positive predictive value of 97.2%, and a negative predictive value of 70.3%; the corresponding values for CT were 39.1%, 92.6%, 90.0%, and 47.2%, respectively. The sensitivity and negative predictive value were significantly higher for (18)F-FDG PET than for CT (P < 0.001 and P = 0.03, respectively).(18)F-FDG PET determination of the extent of neck node involvement changed the neck dissection regimen in 5 patients (27.8%).
SDC of the major salivary gland is a highly metabolic tumor with high (18)F-FDG uptake. (18)F-FDG PET is useful for evaluating neck node status and for determining surgical planning in patients with major salivary gland SDC.
- SourceAvailable from: Punit Sharma[Show abstract] [Hide abstract]
ABSTRACT: OBJECTIVE: The aim of this study was to evaluate the clinical utility of F-fluorodeoxyglucose (F-FDG) positron emission tomography-computed tomography (PET-CT) in staging and restaging of patients with malignant primary salivary gland tumours. METHODS: Data pertaining to 30 patients (age: 43.8±16.8 years; male/female: 20/10) with histopathologically proven malignant primary salivary gland tumours who underwent 36 F-FDG PET-CTs were retrospectively analysed. Ten PET-CTs were performed for staging and 26 for restaging. The primary site was the parotid gland in 22 patients, the submandibular gland in seven and the minor salivary gland in one patient. F-FDG PET-CT images were revaluated by two nuclear medicine physicians in consensus. Findings were grouped into local disease, nodal disease and distant metastasis. Results were compared with those of conventional imaging modalities [CIM (CT/ultrasound/bone scintigraphy)] when available (n=28). Clinical or imaging follow-up (minimum 6 months) data along with histopathological information (when available) were taken as the reference standard. RESULTS: Overall, 25 PET-CTs were positive and 11 were negative for disease. F-FDG PET-CT showed local disease in 21 patients, nodal disease in 17 and distant metastasis in nine (lungs, four; liver, three; bones, four; and thyroid, one). Twenty-three PET-CTs were true positive, nine were true negative, two were false positive and two were false negative. The overall sensitivity of F-FDG PET-CT was 92%, specificity was 82%, positive predictive value was 92%, negative predictive value was 82% and accuracy was 89%. No significant difference was seen in the accuracy of PET-CT between the staging and restaging groups (100 vs. 85%; P=0.468). In patients for whom comparable CIM data were available (n=28), PET-CT did not show any significant advantage over CIM (P=0.012) but was more specific (71 vs. 43%). CONCLUSION: F-FDG PET-CT shows high accuracy in staging and restaging of patients with malignant primary salivary gland tumours. It is more specific than CIM for this purpose.Nuclear Medicine Communications 03/2013; 34(3):211-219. · 1.38 Impact Factor