Long term follow-up in cutaneous malignant melanoma: the relationship of maximal tumour thickness to disease free survival, disease recurrence and death.

284 patients with invasive cutaneous malignant melanoma and known maximal tumour thickness (MTT) were followed up for 10 to 16 years (or to earlier death) following conventional wide margin excision of the primary tumour. Of these 26 (9%) presented with clinical Stage II disease (enlarged regional lymph nodes). The 10 year disease free survival was 45% for clinical Stage I disease, with 5/26 patients with Stage II disease alive 10 years after tumour excision combined with lymph node dissection. Ninety per cent of first tumour recurrences (lymph node or local skin recurrence) occurred within 5 years of primary surgical treatment for clinical Stage I disease, whilst only 63% of deaths from melanoma occurred within this 5 year period. Although maximal tumour thickness is a valuable prognostic guide, cutaneous malignant melanoma remains an unpredictable disease.