The time from diagnostic excision biopsy to wide local excision for primary cutaneous malignant melanoma may not affect patient survival

Background The surgical management of primary cutaneous malignant melanoma usually involves an excision biopsy of the suspected lesion followed by wide local excision. No study has addressed whether a delay between these two surgical procedures influences patient outcome. Objectives To determine if the surgical interval (SI) between the diagnostic excision biopsy and wide local excision for primary cutaneous malignant melanoma affects recurrence or survival outcome. Methods A cohort of 986 patients who had a diagnostic excision biopsy followed by wide local excision was identified from those registered on a specialist database that records the clinicopathological features, surgical treatment and follow-up information of all patients with malignant melanoma in Scotland. The cohort was divided into five arbitrary groups determined by the length of the SI as follows:less than or equal to14 days, 15-28 days, 29-42 days, 43-91 days and greater than or equal to 92 days. Overall survival, disease-free survival and recurrence-free interval between the groups were compared univariately and multivariately. Results The mean age at excision biopsy was 47.4 years and the median period of follow-up was 5 years (range 27 days to 20.7 years). The median SI was 30 days (range 1-468 days). The SI was: (i)less than or equal to14 days for 130 (13%); (ii) 15-28 days for 320 (33%); (iii) 29-42 days for 262 (27%); (iv) 43-91 days for 251 (25%); and (v) greater than or equal to 92 days for 23 (2%) patients. The latter group was older, had thinner melanomas, a higher percentage of lesions on the head and neck, fewer superficial spreading malignant melanomas and ulceration present less often compared with patients treated earlier. Univariately, there was no significant difference in overall survival (P = 0.60) or disease-free survival (P = 0.24) between the groups. Although there was a statistically significant difference in the percentage of recurrence-free patients between the groups (P = 0.011), the better recurrence-free rates occurred in the 29-42 and 43-91 day groups. After adjusting for age, sex, tumour thickness, site, histology, ulceration and mitotic activity using Cox's proportional hazards model, there was no statistically significant difference in overall survival, disease-free survival and recurrence-free percentages between the surgical groups (P = 0.88, P = 0.44 and P = 0.084, respectively). Conclusions There was no evidence that survival outcome or recurrence was related to the time interval between the diagnostic excision biopsy and wide local excision of melanoma.