Tumor thickness as a guide to surgical management of clinical stage I melanoma patients

Abstract

An analysis of failure to control locally recurrent or metastatic melanoma was used to substantiate the value of thickness as a guide to surgical management. There were no local recurrences in patients with melanomas less than 0.76 mm in thickness, regardless of the skin margins excised. The three year actuarial incidence of subsequent regional metastases in patients initially treated by wide local excision (WLE) of their melanoma was directly correlated with tumor thickness (p = <0.001); it was 0% for lesions <0.76 mm, 25% for 0.76 to 1.50 mm lesions, 51% for 1.50 to 3.99 mm lesions and 62% for lesions >4.0 mm in thickness. At five years, patients with melanomas of 1.50 to 3.99 mm thickness who had WLE plus elective regional node dissection (RND) had a calculated 15% incidence of distant metastases and an actuarial survival rate of 83%, while patients with melanomas of the same thickness who had WLE alone as their initial surgical treatment had a 78% incidence of distant metastases and a 37% survival rate (p = 0.001 and 0.01, respectively). In patients with melanomas exceeding 4.0 mm in thickness, the potential benefits of RND were less apparent because of a high risk (>70%) of distant metastases at the time of initial diagnosis. Based upon this analysis, our initial surgical management of melanomas <0.76 is a WLE using a 2.0 cm margin of skin, while thicker lesions are excised using a 3 to 5 cm skin margin. Elective RND is not indicated for lesion C0.76 mm in thickness, but it is considered for 0.76 to 1.50 mm lesions in selected patients and is employed for virtually all patients with lesions exceeding 1.5 mm in thickness. The rationale of elective RND is improved survival in patients with intermediate thickness lesions (0.76 to 3.99 mm) while it is justifiable as a staging procedure for lesions exceeding 4.0 mm thickness.

Prediction of Survival in Patients With Thin Melanoma: Results From a Multi-Institution Study

“…3,9,10 One aim of this study was to investigate whether prognostic factors might predict regional lymph node involvement. We found that MR Ն 1, LVI in the primary tumor, or both were significantly associated with SN positivity.…”

“…However, the 2009 American Joint Committee on Cancer (AJCC) emphasized the variability (85% to 99%) of 10-year survival for thin melanoma. 3 It is important therefore to identify factors that influence prognosis.…”

“…Low-risk (T1a) melanomas are nonulcerated, with an MR of less than one mitosis per square millimeter; higher-risk (T1b) melanomas have an MR of one or more mitoses per square millimeter, ulceration, or both. The Committee noted that regional node metastasis was also an important prognostic factor in early-stage melanoma and recommended sentinel node biopsy (SNB) in selected T1b patients 3 but did not have sufficient data to assess the risk of occult nodal micrometastases in T1 patients.…”

Cutaneous malignant melanoma in Scotland

“…The work of Clark, Breslow, Balch and their associates in the past decade has greatly extended the volume of useful information, often of considerable prognostic significance, which can be obtained from light-microscopic examination of appropriate blocks of paraffin-embedded tissue (Clark et al, 1969;Breslow, 1977;Breslow & Macht, 1978;Balch et al, 1978Balch et al, , 1979Balch et al, , 1980. Clark has suggested that there are several different histogenetic precursors or lateral growth phases of the pre-invasive epidermal component of cutaneous malignant melanoma.…”

Cutaneous malignant melanoma in West Yorkshire: Ii. A prospective study of recurrence and prediction of lymph nodal metastasis

“…Breslow, 1975Breslow, & 1978Holmes et al, 1976;Balch et al, 1979;and Roses et al, 1982). The choice of sex as the second partial regression coefficient may reflect the marked difference in incidence and rate of lymph nodal metastasis observed between males and females (Table II, Figure 2) with the result that they are forming two significantly different groups in this respect.,This view is supported by Weidner et al (1976) who found lymph nodal metastasis to be significantly increased in males, a finding in accord with that of the present study.…”