Risk Factors for Regional and Systemic Metastases in Patients with Sentinel Lymph Node-negative Melanoma.

BACKGROUND

Sentinel lymph node status is a strong prognostic factor in melanoma. However, up to 21% of sentinel lymph node-negative patients develop locoregional and distant metastases during follow-up.

AIM: To analyze risk factors for locoregional and distant metastasis in patients with sentinel lymph node-negative melanoma.

PATIENTS AND

METHODS

A total of 545 patients underwent sentinel lymph node biopsy (SNB) between 2005 and 2013 at our hospital. Data for 449 patients with a negative SNB were analyzed regarding risk factors and development of metastases. Follow-up was performed until 2016.

RESULTS

A total of 72 SNB-negative patients developed metastases, including 25 (34.7%) distant and 47 (63.3%) locoregional metastases. Locoregional metastases occurred earlier compared to distant metastases (with a mean of 24.2 and 23.5 months for regional lymph node and cutaneous metastases, respectively, vs. 31.4 months for distant metastases). Patients with metastases despite negative SNB had a greater tumor thickness (p=0.001), a higher rate of nodular melanoma (p=0.001), ulceration (p<0.001), and were older (p=0.05) compared to SNB-negative patients without subsequent metastases. Out of SNB-negative patients, 16% developed metastases.

CONCLUSION

Close clinical follow-up including sonography of the draining lymph node region is mandatory for melanoma patients regardless of SNB status.