Patterns of first-recurrence and post-recurrence survival in patients with primary cutaneous melanoma after sentinel lymph node biopsy

Sentinel lymph node biopsy (SLNB) has become well accepted in management of patients with primary cutaneous melanoma. An understanding of the pattern of recurrence after SLNB is helpful in coordinating a rational plan of follow-up in these patients. We sought to determine the site and timing of initial recurrence and post-recurrence survival after SLNB. Stage I/II melanoma patients who underwent SLNB during 1991–2004 were identified from a prospective single-institution database. Site and date of first recurrence after SLNB were recorded. Patterns of recurrence after SLNB and post-recurrence survival were analyzed. One thousand and forty-six patients underwent SLNB. The sentinel lymph node (SLN) was positive in 164 patients (16%). Median follow-up was 36 months for survivors. Median and 3-year relapse-free survival for SLN-positive patients were 41 months and 56%, and for SLN-negative patients were not reached and 87%, respectively (P < .0001). Of the SLN-positive patients, 47% experienced recurrence, compared with 14% SLN-negative patients. The pattern of recurrence stratified by SLN status was similar between the two groups (P = NS). After recurrence, the site of recurrence was the only significant prognostic factor influencing survival (P < .0001). Although SLN-positive patients experience recurrence far earlier and more frequently than SLN-negative patients, the pattern of recurrence is similar. After recurrence, its site is the primary determinant of survival.