Histological Immune Response Patterns in Sentinel Lymph Nodes Involved by Metastatic Melanoma and Prognostic Significance

Aims

To further characterize the micromorphometric immunological pattern to metastatic melanoma in SLN biopsies and completion lymph node (CLN) dissections and their relation to 5-year overall survival.

Methods

Retrospective cohort of 49 patients from 1996 to 2005 with a positive SLN who underwent CLN dissection were studied. Micromorphometric characteristics included: follicular center count per profile (FCC), sinus histiocytosis, metastatic size, tumor infiltrating lymphocytes (intranodal), paracortial dendritic cells, germinal center reaction, and morphology. Comparison of Kaplan-Meier survival curves used the exact log rank statistic.

Results

In the high FCC (n5-51) versus the low FCC (n<5) lymph nodes, a delayed separation occurred at 3 years, with 5-year overall survival rates being 73% versus 54% in the high and low FCC groups respectively. Improved survival up to 3-years was also noted in CLDs that demonstrated a higher FCC when compared to the prior SLN. Patients with metastatic deposits >2 mm had significantly lower 5-year survival (both <0.001).

Conclusions

Nodal micromorphometric features (i.e. FCC) are likely related to host immune response to metastasis. Quantitative evaluation of lymphoid follicular centers could provide valuable prognostic information to help to stratify patients.

http://ift.tt/2C03lKO