Our aims were (1) to compare the respective ability of ultrasonography and palpation to detect nodal metastasis during initial staging and follow-up in patients having melanomas and (2) to assess, we believe for the first time, which ultrasound criteria should be used to define metastasis in cases of cutaneous or mucosal melanoma.
Prospective single-center study. Nodal metastasis was confirmed by histopathologic evaluation.
Dermatology and radiology departments of a university hospital.
A total of 160 new consecutive patients with stage I to stage III melanoma.
Experienced operators independently performed 391 paired palpation and ultrasonographic examinations.
Main Outcome Measures
Firm enlarged nodes found on palpation were considered metastatic. On ultrasonographic examination, circular or oval hypoechoic lymph nodes lacking hyperechoic hila were considered metastatic (stringent criteria). Nodes with 2 or fewer of these patterns and other published signs of metastasis (ie, intranodal nodular hypoechoic focus and irregularity of the node margin) were considered suspicious.
Over the 6-year study period 33 patients developed nodal metastasis. For palpation and ultrasonography using the stringent criteria, respectively, sensitivity was 41.5% (95% confidence interval [95% CI], 29.6-53.5) and 76.9% (95% CI, 66.7%-87.2%) (P<.001) and specificity was 95.7% (95% CI, 93.5%-97.9%) and 98.4% (95% CI, 97.1%-99.8%) (P<.05). Including ultrasonographically suspicious lymph nodes significantly lowered specificity (86.2% [95% CI, 82.5-89.9]) (P<.05) without improving sensitivity. Previous lymphadenectomy had little impact on ultrasonographic findings.
Ultrasonography using stringent criteria of nodal metastasis, which are easy to identify and reliable, is superior to palpation for early detection of regional lymph node metastases of melanoma.