Background
Phase III open-label RCT (DeCOG-SLT), N=483 stage III (clinically occult) melanoma with positive sentinel-node biopsy. Non-palpable regional nodes, no distant metastases. Stratified by center and Breslow thickness. Enrolled 2006-2014 across 41 German centers; median Breslow 2.4 mm.
Interventions and follow up
Arm A: Completion lymph-node dissection (CLND) of the sentinel node basin
Arm B: Observation with regular ultrasonographic surveillance of regional nodes
Primary endpoint: Distant metastasis-free survival (DMFS)
mFollow up: 35 months
Arm B: Observation with regular ultrasonographic surveillance of regional nodes
Primary endpoint: Distant metastasis-free survival (DMFS)
mFollow up: 35 months
Results
3-yr DMFS (CLND vs observation): 77.0% vs 79.6%, HR 1.03, 95% CI 0.71-1.50, P=.87 (NS)
DFS: HR 0.77, 95% CI 0.55-1.07, P=.12 (NS)
MSS: HR 0.74, 95% CI 0.48-1.15, P=.19 (NS)
OS: HR 0.78, 95% CI 0.52-1.17, P=.24 (NS)
DFS: HR 0.77, 95% CI 0.55-1.07, P=.12 (NS)
MSS: HR 0.74, 95% CI 0.48-1.15, P=.19 (NS)
OS: HR 0.78, 95% CI 0.52-1.17, P=.24 (NS)
Adverse events
Lymphedema any-grade (CLND vs observation): 27.7% vs 7.3%, P<.001
Wound complications/infection: higher with CLND
Nerve injury: higher with CLND
Key finding: surgical morbidity without oncologic benefit
Wound complications/infection: higher with CLND
Nerve injury: higher with CLND
Key finding: surgical morbidity without oncologic benefit
Conclusions
CLND after positive SLNB did not improve DMFS, DFS, or OS vs observation with ultrasound surveillance in melanoma with occult sentinel-node metastases, while substantially increasing lymphedema risk without oncologic benefit.
Key Limitations
Stopped early for futility and slow accrual; underpowered for subset analyses. Restricted to SLN micrometastases (non-palpable nodes); patients with large SLN deposits or extracapsular extension excluded, limiting generalizability to higher-burden cases. Short median follow-up (35 months) may miss late recurrences. DMFS primary endpoint, though OS more clinically definitive. Concurrent MSLT-II had concordant findings.
Clinical Context
DeCOG-SLT and MSLT-II (NEJM 2017) together established that routine CLND after positive SLNB does not improve melanoma survival. Standard of care after positive SLNB is now active ultrasound surveillance of the regional nodal basin rather than CLND, except for selected patients with bulky nodal disease or macrometastases. Cited in ASCO and ESMO guidelines recommending against routine CLND.