Incomplete sentinel node biopsy is not clearly related to survival or regional recurrence in cutaneous melanoma patients.

BACKGROUND

In melanoma patients, we define incomplete sentinel node biopsy (I-SNB) as when fewer lymph nodes are removed during sentinel node biopsy (SNB) than identified on preoperative lymphoscintigraphy (LS). This study quantifies the frequency of I-SNB and evaluates any correlation with patient outcomes.

METHODS

Evaluation of a prospective database of consecutive patients having LS and negative SNB from 1996 to 2006. Additional LS information was obtained from a nuclear medicine database. All statistical analyses were performed using the IBM SPSS Statistic 19.0 software package.

RESULTS

I-SNB occurred in 20% of the cohort (n = 2007). For axillary (n = 895), groin (n = 569), and neck/axial patients (n = 334) I-SNB occurred in 12%, 26%, and 28% of cases, respectively (P < .001). On univariate analysis, there was a significant association between I-SNB and worse disease-free survival (DFS), P = .007 and trend toward worse melanoma-specific survival (MSS), P = .056. I-SNB was not associated with worse regional recurrence-free survival (RRFS), P = .144. There was no relationship between I-SNB and worse DFS, RRFS, or MSS on multivariate analysis. Sentinel node region (axilla better than groin and neck/axial) had a significant association with RRFS (P = .039) on univariate analysis and DFS on univariate (P = .009) and multivariate analysis. Significantly worse outcomes for MSS, DFS, and RRFS were seen with male gender, increasing age, high mitotic count, ulceration, and increasing Breslow thickness.

CONCLUSION

This study demonstrates no statistically significant relationship between I-SNB and patient outcomes when adjusting for known prognostic factors. These data do not exclude the possibility that I-SNB may have a weak association with worse outcomes.