Upgrading the Diagnostic Assessment in Primary Pulmonary Carcinoids: The Tumor-infiltrating Lymphocytes (TILs)

Adoptive cell transfer (ACT) of autologous tumor-infiltrating lymphocytes (TILs) to treat malignant melanoma: the dawn of a chimeric antigen receptor T (CAR-T) cell therapy from autologous donor

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) are B, T-helper, and T-cytotoxic lymphocytes migrated from the blood or lymph stream toward a tumor with the aim to infiltrate and destroy it. They can be histologically graded as brisk, nonbrisk, or absent. Malignant melanoma has been the first malignancy found to be correlated with TILs status, being brisk TILs associated with better clinical outcomes. By the terminology of "adoptive cell transfer" (ACT), the medical oncology refers to the transfer of cells in a tumor-bearing patient from the same recipient or a healthy donor.

METHODS

A PubMed literature search on the topic has been performed. Additional documents known to the authors and identified from the reference list of cited publications have been included.

RESULTS

In the past, autologous TILs ACT was successfully tested for the treatment of malignant melanoma and, today, it is a standardized procedure in several centers around the world. It represents the first research step toward the bioengineered chimeric antigen receptor T (CAR-T) cell therapy from autologous donor.

CONCLUSIONS

Both autologous TILs ACT and CAR-T cell therapy from autologous donor exploit the anticancer power of targeted self-lymphocytes, but CAR-T cell technology also virtually allows treatment of those melanomas devoid of TILs or with so few cytotoxic TILs that are difficult to identify.

Appendix Tumor Microenvironment

The pathological features of the appendix tumors fundamentally recall those of the more frequent colorectal neoplasms, although with a higher relative incidence of carcinoids, due to the abundant presence of enteroendocrine cells in the appendix wall. Moreover, different types of lymphomas, Hodgkin and non-Hodgkin, arising from the extra-nodal mucosal-associated lymphatic tissue, can be encountered. The appendix tumor microenvironment (TME) consists of a cellular component and of a noncellular component: the former includes the immunocompetent cells, while the latter represents the support stroma. Particularly in carcinoids, the immune cell reaction can be explicated by tumor-infiltrating lymphocytes, which, in some circumstances, may arrange around and inside the tumor in a brisk fashion influencing favorably the prognosis. This active reaction has to be distinguished from any preexisting inflammatory condition of the appendix and from superimposed tumor complications, such as infection or ischemia. In practice, we consider the appendix TME a complex framework with immunological, mechanic, and metabolic functions, all supported by a marked neo-lymphoangiogenesis.