Related Experiment Video
Updated: Oct 5, 2025
08:42
Establishment of a Co-culture System of Patient-Derived Colorectal Tumor Organoids and Tumor-Infiltrating Lymphocytes (TILs)
Published on: June 27, 2025
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Is There a Relationship Between TILs and Regression in Melanoma?
Steven Morrison1, Gang Han2, Faith Elenwa2
1Division of Surgical Oncology, Oregon Health and Science University, Portland, OR, USA.
Annals of Surgical Oncology
|January 22, 2022
Summary
Tumor-infiltrating lymphocytes (TILs) correlate with melanoma regression, but only TILs, not regression itself, significantly predict sentinel lymph node metastasis and overall survival. The impact of regression on patient outcomes depends on the presence of TILs.
Area of Science:
- Oncology
- Immunology
- Pathology
Background:
- The prognostic significance of tumor-infiltrating lymphocytes (TILs) and tumor regression in melanoma remains unclear.
- This study investigates the association between TILs and regression in a large, multicenter melanoma patient cohort.
Purpose of the Study:
- To assess the relationship between TILs and regression in melanoma.
- To determine the independent and combined prognostic value of TILs and regression on sentinel lymph node (SLN) metastasis and overall survival (OS).
Main Methods:
- A retrospective analysis of 2450 melanoma cases from the Sentinel Lymph Node Working Group database (1993-2018).
- Clinicopathologic factors, TILs status, regression, SLN status, and OS were analyzed.
- Statistical correlations were performed to evaluate associations.
Main Results:
- TILs were present in 73.9% of cases, and regression was observed in 18.1% of cases with TILs.
- The presence of TILs was significantly associated with regression (p < 0.0001) and negative SLN status (p < 0.05).
- TILs, but not regression, were significantly associated with improved overall survival (OS). The prognostic impact of regression was dependent on TIL presence.
Conclusions:
- Regression is strongly correlated with TILs in melanoma.
- Only TILs, independent of regression, significantly predict SLN metastasis and OS.
- The clinical impact of regression on melanoma patient outcomes is contingent on the presence or absence of TILs.
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