Risk factors and timing of subsequent cutaneous squamous cell carcinoma in patients with cutaneous squamous cell carcinoma: a retrospective cohort study

Marla Rodriguez, BS • Brandon T. Beal, MD • Manisha Manmohan, MD • Isaac N. Briskin, MA • Thomas Knackstedt, MD • Allison T. Vidimos, MD, RPh

Published: August 26, 2020 DOI:https://doi.org/10.1016/j.jaad.2020.08.083

Abstract

Background

Information about the frequency and timing of subsequent cutaneous squamous cell carcinoma (cSCC), along with associated risk factors, is limited. However, this information is crucial to guide follow-up care for these patients.

Objective

Evaluate the risk and timing of subsequent cSCC in patients who presented with initial diagnosis of cSCC.

Methods

Retrospective review of IRB-approved single institution registry of invasive cSCC. All patients had at least two primary cSCCs diagnosed on two separate dates 2-months apart.

Results

299 primary cSCCs were included. 6-months from initial cSCC diagnosis, 18.06%(n=54) of patients developed subsequent cSCC; at 1-year 31.77%(n=94), 3-years 67.56%(n=202), and 5-years 87.96%(n=263) developed subsequent cSCC. Risk factors associated with subsequent cSCC include age at initial diagnosis (HR=1.02, 95% CI=[1.004, 1.027], p=0.008), T2 stage (HR=1.66, 95% CI=[1.07, 2.57], p=0.025), and poor tumor grade. Tumor grades well, moderate, and unknown have HRs of 0.21 (p = <0.001), 0.16 (p = <0.001), and 0.25 (p = 0.001), respectively.

Conclusions

Of patients that develop subsequent cSCC, 18.06% do so within 6-months and 31.77% do so within 1-year of initial cSCC diagnosis. Patients with advanced age, poor histologic differentiation, and AJCC T2 stage are at highest risk. Close clinical follow-up after initial diagnosis is recommended.