Findings of computed tomography in stage IIB and IIC melanoma: a six-year retrospective study in the South-East of Scotland.

Introduction: Patient prognosis in malignant melanoma is directly related to clinical stage, and accurate staging is key to appropriate management. Revised BAD/BAPS (British Association of Dermatologists/British association of Plastic Surgeons) 2010 guidelines for the management of cutaneous melanoma recommend that Computed Tomography (CT) is no longer indicated for AJCC (American Joint Cancer Committee) IIB and IIC disease (Breslow thickness 2.01 - 4 mm with ulceration or >4 mm), unless the patient is symptomatic. Previous UK guidelines had recommended that all patients with AJCC IIB or worse disease should have chest, abdomen and pelvic CT as staging investigations. New guidelines also now include head CT in their recommendations. Our aim was to investigate regional CT findings in those patients diagnosed with AJCC IIB and IIC disease, and establish whether our findings affirmed new UK guidelines. METHODS AND PATIENT GROUP: A retrospective review of case notes was performed on 172 cases of AJCC IIB and IIC disease referred across Lothian, Borders and Fife to melanoma services during the period of January 2004 to January 2010. Clinical findings, results of initial and follow-up CT scans along with changes in patient management were noted. Chest, abdomen and pelvic CT scan were defined as one scan as they were always performed together. CT head and CT neck were defined as separate scans. A positive CT result was defined as those reported with metastasis or an indeterminate result leading to further investigations. Change in management was defined as specific active treatment started or stopped eg surgery or chemo/radiotherapy.

Results: A total of 269 scans were performed on 130/172 patients. One hundred and four initial staging CT scans were performed on 75 patients, and detected one (1.3%) occult melanoma metastasis. At follow-up, 165 scans were performed in 82 patients and detected 56 metastasis in 32(39%) patients leading to a change in management in 29(35%). Two of these 32 patients had occult melanoma metastasis. Symptomatic patients had statistically significant more metastatic disease diagnosed at follow-up CT scanning than asymptomatic patients p < 0.0001. Head CT detected 15/56 (27%) of all metastasis.

Conclusion: CT scanning should only be performed in AJCC IIB and IIC melanoma patients if symptoms of clinical metastatic disease are present. Head CT should be included in the staging process. Our regional results concur with new BAD/BAPS 2010 guidelines.