The Integrated Role of Ultrasonography in the Diagnosis of Soft Tissue Metastases from Melanoma: Preliminary Report of a Single-center Experience and Literature Review

Currently melanoma has the fastest growing incidence of all cancers in men and the second in women (after lung cancer) in Western countries. Since prognosis of skin melanoma is excellent in early stages but dramatically worsens in advanced stages, an early diagnosis is fundamental in granting patients a favorable outcome. Sentinel node (SN) biopsy represents the gold standard for accurately staging melanoma, but other tests are commonly endorsed both in the initial staging work-up and in the follow-up, such as ultrasonography, computed tomography (CT)-scan and positron emission tomography (PET)-CT. PET-CT, among others, has high sensitivity and specificity for the study of distant metastases, the assessment of soft tissues and lymph node involvement, and for the guidance of surgical biopsies. Ultrasonography (US) is a non-invasive procedure whose use has recently expanded in our service, both preoperatively, intraoperatively and postoperatively, thanks to its wide availability, low costs and easy and fast reproducibility; ultrasonography even surpassed the reliability of PET-CT or CT-scan in the seven cases presented herein. US is operator-dependent, and this is probably the major limitation of the procedure, together with lack of prospective studies validating its strength, but our preliminary study demonstrates that ultrasound can assume an important role in melanoma, both for staging and the follow-up of patients, especially with lymph nodal or subcutaneous involvement. Malignant melanoma represents an emerging social problem in Western countries, since its incidence has risen faster than any other malignancy in Caucasian populations over the last 30 years (1); in fact, melanoma has the fastest growing incidence of all cancers in men and is second in incidence in women, after lung cancer (2). The average age at diagnosis is 59 years and the disease has second place after leukemia for loss of potential years of life (3). In 2009, the American Cancer Society estimated 68,720 new cases of melanoma in the United States, with 8,650 disease-related deaths (4). Similar data are also provided for Europe, with slightly higher incidence in Northern countries (5). The estimates for Italy indicate 143 new cases/year every 1,000,000 men and 136/year every 1,000,000 women, with approximately 1,500 deaths per year (6).