Biopsia de ganglio centinela en melanoma. Valor pronóstico y correlación con el índice mitótico. Experiencia en un hospital terciario

Predictors of sentinel lymph node positivity in thin melanoma using the National Cancer Database

BACKGROUND

Sentinel lymph node biopsy (SLNB) specimens are often obtained from patients for further staging after these patients have undergone melanoma excision. Limited data regarding predictors of SLNB positivity in thin melanoma are available.

OBJECTIVE

We sought to evaluate predictors of SLNB positivity in thin melanoma.

METHODS

Patients with cutaneous melanoma with a Breslow thickness ≤1.00 mm who received a SLNB were identified from the National Cancer Database between 2004 and 2014 (n = 9186). Predictors of SLNB positivity were analyzed using logistic regression.

RESULTS

In a multivariate analysis, patients <60 years of age (P < .001) and Breslow thickness >0.8 mm (P = .03) were at increased risk for positive sentinel lymph node (SLN). Moreover, on multivariate analysis, the presence of dermal mitoses increased the odds of SLN positivity by 95% (odds ratio [OR] 1.95 [95% confidence interval {CI} 1.53-2.5], P < .001), ulceration by 63% (OR 1.63 [95% CI 1.21-2.18], P < .001), and Clark level IV to V by 48% (OR 1.48 [95% CI 1.19-1.85]). Patients without ulceration but with dermal mitoses had 92% (OR 1.92 [95% CI 1.5-2.48], P < .001) increased SLN positivity.

LIMITATIONS

Limited survival data are available.

CONCLUSIONS

Younger age, a Breslow thickness >0.8 mm, the presence of dermal mitoses, ulceration, and Clark level IV to V are positive predictors of positive SLN. While the new American Joint Committee on Cancer system has removed dermal mitotic rate from staging, continued evaluation of dermal mitotic rate could be valuable for guiding surgical decision making about SLNB.

[Sentinel lymph node biopsy in melanoma: our experience over 8 years in a universitary hospital]

BACKGROUND

Since the introduction of sentinel lymph node biopsy, its use as a standard of care for patients with clinically node-negative cutaneous melanoma remains controversial. Our experience of sentinel lymph node biopsy for melanoma is presented and evaluated.

MATERIAL AND METHODS

A cohort study was conducted on 69 patients with a primary cutaneous melanoma and with no clinical evidence of metastasis, who had sentinel lymph node biopsy from October-2005 to December-2013. Sentinel lymph node biopsy was identified using preoperative lymphoscintigraphy and subsequent intraoperative detection with gamma probe.

RESULTS

The sentinel lymph node biopsy identification rate was 98.5%. The sentinel lymph node biopsy was positive for metastases in 23 patients (33.8%). Postoperative complications after sentinel lymph node biopsy were observed in 4.4% compared to 38% of complications in patients who had complete lymphadenectomy.

CONCLUSION

The sentinel lymph node biopsy in melanoma offers useful information about the lymphatic dissemination of melanoma and allows an approximation to the regional staging, sparing the secondary effects of lymphadenectomy. More studies with larger number of patients and long term follow-up will be necessary to confirm the validity of sentinel lymph node biopsy in melanoma patients, and especially of lymphadenectomy in patients with positive sentinel lymph node biopsy.