Prognosis in Patients With Sentinel Node–Positive Melanoma Is Accurately Defined by the Combined Rotterdam Tumor Load and Dewar Topography Criteria

Abstract

Patients with metastases < 0.1 mm, especially when present in the subcapsular area only, may be overtreated by a routine CLND and have an MSS that is indistinguishable from that of SN-negative patients. Thus the RDC criteria provide a rational basis for decision making in the absence of conclusions provided by randomized controlled trials.

Malignant Melanoma S3‐Guideline “Diagnosis, Therapy and Follow‐up of Melanoma”

“…According to published data, a combination of various parameters of tumor load and location of the micrometastasis provides the best potential for gauging involvement of N-SLN. When considering both size criteria and Dewar classification, a group of subcapsular metastases < 0.1 mm was identified at very low risk (2 %) for positive N-SLN [213]. In a retrospective analysis of patients with the lowest scores, the "Hannover system" [193], developed from [190]), which is based on the combination of maximum diameter of metastases (cut-off 0.1 mm), TPD (tumor penetrative depth, cut-off 2 mm) and capsular infiltration (present/not present), yielded overall and recurrence-free survival rates similar to SLNnegative patients.…”

“…Besides the length of the largest tumor cluster (limit value 0.1 mm), another study revealed the anatomic location according to Dewar as prognostic factor [213].…”

“…Unlike clinically or radiologically obvious macrometastases, micrometastases to the sentinel lymph node (SLN) occur significantly more often as the only manifestation of lymph node involvement and carry a markedly better survival prognosis [209]. In patients with micrometastasis to the SLN, the overall risk for metastasis to additional non-sentinel lymph nodes (N-SLN) is roughly 20 % (16 %-21 %, [205,209,213]. Within this prognostically inhomogeneous patient group [17,209], it is therefore necessary to identify those patients at low risk for positive N-SLN who do not require completing lymph node dissection (CLND) following SLNB.…”

“…mammary carcinoma < 0.2 mm = submicrometastases) that would aid in proper assessment of tumor load and reliably facilitate the decision as to the need for subsequent CLND [210]. The number of additionally positive N-SLN and the survival prognosis have been shown to depend on 1) the maximum diameter of metastasis and the location within the sentinel node [190,193,205,211], 2) the "area" of metastasis in the histologic section (absolute or relative to the cross-sectional area of the lymph node) [190,205,212], 3) the depth of invasion measured from the capsular margin (Starz classification) [190,193,205], 4) the number of positive SLN [193], 5) the microanatomic location with respect to the lymph node capsule ("Dewar criterion"), and 6) capsular infiltration [190,193,205] (reviews in [210,213]). According to published data, a combination of various parameters of tumor load and location of the micrometastasis provides the best potential for gauging involvement of N-SLN.…”

“…Different parameters have been described. Among them are: 1. number of involved sentinel lymph nodes [17,209], 2. maximum diameter of the metastasis [190,193,196,204,[211][212][213]], 3. "area" occupied by the metastasis in the histologic section (absolute or relative to the cross-sectional area of the lymph node) [190,205,212,214], 4. presence of isolated melanoma cells versus cell clusters [215], 5.…”