Cutaneous squamous cell carcinoma and mortality in end-stage renal disease

Introduction

Cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in the United States with approximately 1.8 million cases diagnosed annually.

The majority of cSCC can be treated with medication, local destruction, or surgical excision. However, a history of cSCC is associated with higher all-cause mortality compared to the general population. The exact mechanisms by which cSCC increases all-cause mortality are continuing to be discovered, with cSCC patients found to be at increased risk of death from heart disease, vascular disease, cancer, and infection, among others. Studies have suggested that immunosuppression may play an important role in cSCC and subsequent mortality. Organ transplant recipients on immunosuppressive therapies have been found to have an increased risk of skin cancer, and they are roughly 100 times more likely to develop cSCC. ^, Additionally, skin cancer in organ transplant recipients is associated with greater all-cause mortality: a study of American organ transplant patients found that mortality from skin cancer in these patients is nearly 9 times greater than that in the general population, in terms of deaths per person-years at risk. Indeed, cSCC is the most commonly encountered post-transplant malignancy, with a more frequent occurrence, greater metastasis and a higher rate of recurrence in transplant recipients compared to the general population, leading to increased mortality. ^, The increased risk for cSCC occurrence has been attributed to the use of immunosuppressant medications to prevent organ rejection. ^, A state of immune dysfunction has been widely reported in patients living with end-stage renal disease (ESRD) as well. Uremic toxins and dialysis-related factors can act as both immune stimulators and inhibitors. As a result, an increased risk of cSCC has also been found in some ESRD patients: a study in Taiwan found that patients on chronic hemodialysis were at higher risk of non-melanoma skin cancers. However, the impact of cSCC on mortality in ESRD has yet to be examined. To evaluate all-cause mortality in cSCC among ESRD patients, we compared mortality in ESRD patients with and without cSCC, specifically excluding solid organ transplant recipients, to reduce the impact of this group on mortality in association with a diagnosis of cSCC.