Post-thymic CD4 positive cytotoxic T cell infiltrates of the skin: A clinical and histomorphologic spectrum of the unique CD4 positive T cell of immunosenescence

Immunosenescence and Skin: A State of Art of Its Etiopathogenetic Role and Crucial Watershed for Systemic Implications

Immunosenescence is a complex multifactorial phenomenon consisting of wide-ranging remodeling of the immune system during the life span, resulting in an age-related qualitative-quantitative decline of immune cells and cytokines. A growing body of evidence in the international literature is highlighting the etiopathogenetic role of skin immunosenescence in the onset of various dermatologic conditions. Skin immunosenescence also serves as an interesting watershed for the onset of system-wide conditions in the context of allergic inflammation. Moreover, in recent years, an increasingly emerging and fascinating etiopathogenetic parallelism has been observed between some mechanisms of immunosenescence, both at cutaneous and systemic sites. This would help to explain the occurrence of apparently unconnected comorbidities. Throughout our review, we aim to shed light on emerging immunosenescent mechanisms shared between dermatologic disorders and other organ-specific diseases in the context of a more extensive discussion on the etiopathogenetic role of skin immunosenescence. A promising future perspective would be to focus on better understanding the mutual influence between skin and host immunity, as well as the influence of high inter-individual variability on immunosenescence/inflammaging. This can lead to a more comprehensive "immunobiographic" definition of each individual.

Primary cutaneous peripheral T-cell lymphoma, not otherwise specified, associated with lymphomatoid papulosis after a 9-year follow up: A case report

Lymphomatoid papulosis (LyP) is a self-limiting cutaneous T-cell lymphoproliferative disorder that may progress into malignant lymphoma. Most of the previously reported associated lymphomas are primary cutaneous anaplastic large-cell lymphoma and mycosis fungoides with a low mortality rate. We report a case of primary cutaneous peripheral T-cell lymphoma, not otherwise specified (pcPTCL-NOS), associated with LyP after long-term follow up. The patient was a 79-year old Japanese man followed up for 9 years. He suddenly developed a 3-cm ulcerated lesion on his forehead, which was diagnosed as an exacerbation of LyP. The lesion regressed after conservative treatment, but the patient soon developed multifocal pcPTCL-NOS. Thereafter, the patient developed pneumonia and cerebral infarction and died within a few months of the onset of malignant lymphoma. Aggressive cutaneous lymphoma may develop in LyP patients. The present case re-emphasizes the need for careful follow up of patients with persistent LyP.