Keratinocyte Cancer Mortality in Kidney Transplant Recipients

Prognostic Outcomes of Cutaneous Squamous Cell Carcinoma in Solid Organ Transplant Recipients: A Retrospective Comparative Cohort Study

INTRODUCTION

Cutaneous squamous cell carcinoma (cSCC) is the second most common cutaneous neoplasm, and its incidence is on the rise. While most cSCCs have an excellent prognosis, certain risk factors, especially immunosuppression, have been associated with higher rates of local recurrence (LR), metastasis, and poor prognosis. This study aims to assess the risk factors for LR and metastasis development in cSCC among solid organ transplant recipients (SOTRs) and compare these rates with those in immunocompetent patients.

MATERIALS AND METHODS

A retrospective observational study included cSCC cases from the University Hospital Reina Sofía in Córdoba, Spain, between 2002 and 2019. Demographic, clinical, and histopathological data were collected. Local recurrence and metastasis rates were analyzed, along with progression-free survival. Univariate analyses were performed to identify prognostic factors in SOTRs.

RESULTS

Among 849 cSCC cases, we found higher rates of local recurrence and metastasis in tumors developed by SOTRs compared to those in immunocompetent individuals. However, no significant differences in local recurrence, metastasis, or progression-free survival were observed between the two groups. Risk factors for adverse outcomes in SOTRs included tumor size > 2 cm, depth > 4 mm, and a higher Clark level. A total of 34.4% of SOTRs developed a second primary cSCC during the follow-up.

CONCLUSIONS

In our study, cSCCs in SOTRs did not exhibit statistically significant differences in the rates of adverse outcomes compared to immunocompetent patients. The prognosis of cSCCs in SOTRs may be more related to other tumor-dependent risk factors than to the immunosuppression status itself. Future studies are needed to refine risk stratification and follow-up protocols to ensure the optimal management of high-risk cSCC cases, particularly among immunosuppressed patients.

Lymphocyte subsets and Langerhans cells in the skin of kidney transplant recipients under three different immunosuppressive regimens

BACKGROUND

Renal transplant recipients (RTRs) are at increased risk of developing skin cancer; however, the role of immunosuppression is not yet fully understood. In this study, we evaluated the immunohistochemical changes in the skin of RTRs under three different immunosuppression regimens: mTOR inhibitors (mTORi), sirolimus or everolimus, mycophenolic acid (MPA) precursors such as mycophenolate sodium or mofetil, or azathioprine (AZA).

METHODS

We evaluated biopsies of sun-exposed and sun-protected skin for immunohistochemical quantification of B lymphocytes (CD20+), T lymphocytes (CD3+, CD4+, and CD8+), and Langerhans cells (LCs) (CD1a+) in 30 RTRs and 10 healthy controls. The RTRs were divided into three groups: mTORi (n = 10), MPA (n = 10), and AZA (n = 10).

RESULTS

No differences were observed in the number of B lymphocytes. However, a significant decrease in the number of T lymphocytes and LCs was observed in both sun-protected and sun-exposed skin in the AZA and MPA groups, although to a lesser degree in the latter group. The skin of the mTORi group did not differ from that of the control group in terms of the number of B and T lymphocytes and LCs.

CONCLUSIONS

Patients treated with mTORi exhibit preserved cellular elements related to cutaneous immune surveillance. The use of AZA induced a greater degree of skin immunosuppression than in the control group, as demonstrated by the decrease in T lymphocytes and LCs.