Affiliation:
1. Division of Plastic and Reconstructive Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
2. Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
3. Institute of Brain Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
4. Department of Surgery, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
5. Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
Abstract
Background:
Tumor staging is crucial for melanoma, of which acral melanoma is the predominant subtype in Asians. 18F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) and 18F-FDG-PET/computed tomography (18F-FDG-PET/CT) serve as noninvasive imaging tools for tumor staging. However, the literature is scarce on the diagnostic value of PET for acral melanoma.
Methods:
From January 1, 2006 to November 30, 2022, a total of 352 patients were diagnosed with melanoma at our hospital. Of them, 90 were diagnosed with cutaneous melanoma and underwent preoperative PET/CT for staging and sentinel lymph node biopsy or complete lymph node dissection. Staging of PET/CT was confirmed by histopathology or following imaging. The lymph node biopsy, distant metastasis status, and PET/CT imaging results were analyzed.
Results:
Of all the 90 patients with cutaneous melanoma, 72 of them were diagnosed as acral melanoma (80.0%). Compared with the histopathologic results, the lymph nodes were true-positive, true-negative, false-positive, and false-negative in 12, 54, 7, and 17 cases, respectively. The sensitivity of PET/CT for local lymph nodes was 41.4% (95% CI, 23.5%-61.1%), whereas its specificity was 88.5% (95% CI, 77.8%-95.3%). As for the detection of distal metastasis, the PET results were true-positive, true-negative, false-positive, and false-negative in 6, 65, 15, and 4 cases, respectively. The sensitivity of PET for distal metastasis detection was 60.0% (95% CI, 26.2%-87.8%), whereas its specificity was 81.3% (95% CI, 71.0%-89.1%).
Conclusion:
Although noninvasive, PET/CT has relatively low sensitivity in regional lymph node evaluations, and fair sensitivity in distal metastasis detection in Asian patients with acral melanoma. Thus, PET/CT may be more useful in patients with clinically palpable nodes or more advanced disease stages.
Publisher
Ovid Technologies (Wolters Kluwer Health)