Prognostic value of sentinel lymph node biopsy according to Breslow thickness for cutaneous melanoma.

BACKGROUND

Sentinel lymph node (SLN) biopsy is widely performed for melanoma with certain histologic parameters and offers important prognostic and staging information. Breslow thickness (BT) by itself also provides meaningful prognostic information.

OBJECTIVE

To evaluate whether SLN status provides prognostic information independent from that which is already provided by BT.

METHODS

We conducted a retrospective cohort study of 896 patients who underwent SLN biopsy for primary cutaneous melanoma. Stratified analysis of the impact of SLN status within BT groups (0.01-1 mm, 1.01-2.00 mm, 2.01-4.00 mm, and >4.00 mm) was performed. In addition, a Cox proportional hazard model was fit to evaluate the interaction between BT unadjusted and then adjusted for SLN status to determine whether predictive ability is improved.

RESULTS

Having a negative SLN did not confer a statistically significant survival advantage for any BT subgroup (P = .54, .075, .17, and .95 for subgroups 0.01-1 mm, 1.01-2.00 mm, 2.01-4.00 mm, and >4.00 mm, respectively). In multivariate analysis, SLN status did not demonstrate independent prognostic ability over that of BT alone (P = .067).

LIMITATIONS: Retrospective study, single institution.

CONCLUSION

Our data suggest that SLN status does not offer better prognostic information for patients than BT alone.