Purpose: Tumor infiltrating lymphocytes (TILs) in cutaneous malignant melanoma are classified as brisk, non-brisk or absent. Numerous studies suggest the presence of TILs, especially brisk, are associated with a lower rate of lymph node metastasis and with an improved overall survival (OS). Our purpose was to assess the value of TILs as a prognostic factor for the lymph node metastasis and survival in completely resected pT3 stage malignant melanoma patients.
Methods: We included a number of 114 patients with pathological pT3 cutaneous malignant melanoma, treated exclusively in our institution, between 2000-2015. Correlations of clinical and pathological factors with lymph node status and OS were analyzed.
Results: A brisk infiltrate was present in 60% of the patients, whereas 40% presented a non-brisk infiltrate or absent TILs. In univariate analysis, the presence of ulceration was correlated with a non-brisk infiltrate, whereas in multivariate analysis, lymph node invasion and a non-brisk infiltrate were associated with a higher risk of death.
Conclusions: TILs density grade represents an independent prognostic factor for the OS. Therefore, we conclude that an accurate prognosis may be provided by TILs status in patients with pT3 malignant melanoma.