gms | German Medical Science

Question: Melanoma is the deadliest of all skin cancers. Even small tumours may have metastasis and a relatively unfavourable prognosis [1], [2]. Melanoma has become a significant public health problem in many countries [3], [4]. While the number of melanoma cases worldwide is increasing faster than any other cancer, mortality rates have increased at a significantly lower rate. Like the other forms of cancer, the most successful treatments are those started at the earliest possible stage of disease [5]. Therefore, early recognition and the best possible treatment that is appropriate excision, lead to a cure rate of over 90% in low risk melanoma patients are very important [3], [6]. One of the major controversies in the primary management of melanoma is that how much surrounding normal skin should be excised around a primary cutaneous melanoma [7]. So in order to reach to narrower safe margin, for the first time we investigated the impact of the excision of primary melanoma with more than 2 mm thickness with 1 cm surgical margins on survival of the patients in comparison to the excision of melanoma with 2 cm surgical margins.

Methods: We performed a population-based survey of melanoma management (NCT02088762) using database of patients from Bern University Hospital from May 1996 to March 2012. primary melanoma tumor with >2 mm thickness, without evidence of metastasis at the time of surgery and treated by excision of the lesion were included in the study. Data collected included patient gender, age, tumor location, tumor type, Breslow thickness, tumor type, presence of ulceration. During this time some consultants in our center, performed primary melanoma excision for the patients according to the current acceptable guidelines and for the 95 of the patients tumor excised with 2 cm margin, while the other surgeons excised all of them with 1 cm margin independent from Breslow depth and Sentinel lymph node biopsies were taken and the patients were accidentally categorised into the two groups according to the excision margins of their tumors. We added the data of the distant and locoregional metastases, which were detected clinically, confirmed by biopsy. Finally the disease free survival and overall survival were calculated for both groups. Then outcomes of the patients in the groups were compared according to the local recurrences, distant and locoregional metastases, disease free survival and overall survival.

Result: Of the 368 patients with thick melanoma enrolled in the study, 307 patients with mean age of 61.05 ±14.59 years were considered in the analyses. The mean Breslow’s depth of primary melanoma tumors for the study patients was 4.39 mm ±4.17 mm (2.10 mm- 45.00 mm). The median follow-up for the patients was 1867 days. Nodular melanoma (69.71%) was the most frequent and amelanotic melanoma in our study population. It should be added that 129 (42%) patients had ulceration in their tumors, 103 patients (33.55%) in our study presented positive sentinel lymph node biopsy, and death attributable to melanoma occurred in 54(17.6%) patients. The patients were categorised into two groups according to the excision margins of their tumors. 212 of the patients underwent tumor excision with 1 cm skin margin, while for the 95 of the patients tumors were excised with 2 cm margin. Statistical analysis of tumour characteristics (tumor thickness, primary tumor location, tumor type, sentinel lymph node biopsy findings) showed no significant differences between two groups, except ulceration which was significantly detected more in 1 cm-Group. Although ulceration was seen more in 1cm-Group analyse of data of locoregional and distant metastases (in order to compare the outcome) did not present any evidences of significant statistical differences between the two groups of this study (P=.271, and .667, respectively) during the mentioned follow up period. Death attributable to melanoma was not significantly different in study patients, as well (18.92% vs 18.95%, respectively) (p=.746). Moreover, Kaplan-Meier methods which were used to compare the survival outcome between study groups, interestingly showed that disease free survival and overall survival were not significantly different between the 1 cm-Group and 2 cm-Group study (p= .926 ,and .902 respectively). In a Cox Regression analysis on the patients with 1 cm excision margins vs the patients with 1 cm excision margins, the estimated hazard ratio for disease free survival (Figure 1 [Fig. 1]) and overall survival (Figure 2 [Fig. 2]) were 1.019 (95% confidence interval, 678-1.533), and 1.037 (95% confidence interval, .585-1.836), respectively.

Conclusion: As the results of our study showed excision of thick melanoma could be done with narrower margins than current protocols, and 1 cm excision margin is sufficient for thick melanoma, which can be safely performed in an outpatient setting under local anesthesia with smaller surgical, less morbidities and expense for flap or graft reconstruction [8]. So, we believe that current accepted melanoma excision protocols should be revised , as a result a prospective randomized multicenter study is demanded to evaluate the proposed surgical margin in this study and compare it with current recommended margins in more details a is demanded.