OBJECTIVES: Keratoacanthoma (KA) and early-stage cutaneous squamous cell carcinoma (cSCC) are known adverse events for several cancer medications. This study aimed to estimate treatment costs of overall incident KA/cSCC patients and by presence/absence of cancer diagnosis in a US claims database.

METHODS: This retrospective analysis examined commercial and Medicare Advantage patients ≥18 years incurring ≥1 pathology claim with a KA/cSCC ICD-10-CM diagnosis identified between 29 June 2016 and 02 November 2019; ≥1 KA/cSCC treatment or biopsy claim within ±1 month of KA/cSCC pathology claim was required. The first KA/cSCC pathology/treatment/biopsy claim set the index date and started the first treatment-episode (TE). Continuous pre- and post-index 6-month health plan benefits were required. Patients with prior KA/cSCC diagnosis, pregnancy, clinical trial participation, or advanced cSCC treatment were excluded. TEs were separated by ≥60-day periods without KA/cSCC pathology/treatment/procedures. KA/cSCC-specific healthcare utilization and costs for TEs and a 6-month post-index period were quantified using claims with KA/cSCC diagnoses and treatments. Patients with/without a pre-index primary cancer diagnosis (PPC+/PPC–) were identified using ICD-10-CM diagnosis codes. Descriptive analysis was conducted.

RESULTS: 7,626 KA and 65,808 cSCC patients satisfied eligibility criteria. 99.5% of TEs (n=79,051) included ≥1 KA/cSCC ambulatory visit. The most prevalent KA/cSCC treatment per TE was excision/destruction (KA, 44% [n=3,490]; cSCC, 86% [n=61,694]); biopsy was present for 76% (n=6,095) of KA and 66% (n=47,232) of cSCC TEs. 3.6% of KA and 5.3% of cSCC patients were PPC+. Mean(SD) KA/cSCC costs per TE were $550($2,609) for KA (PPC+, $530[$650]; PPC–, $551[$2,655]; p=0.675) and $1,041($2,421) for cSCC (PPC+, $1,303[$4,276]; PPC–, $1,026[$2,272]; p=<0.001). Mean(SD) KA/cSCC costs per 6-month post-index period were $614($2,703) for KA (PPC+, $645[$900]; PPC–, $613[$2,747]; p=0.610) and $1,247($2,676) for cSCC (PPC+,$1,610 [$4,600]; PPC–, $1,226[$2,524]; p<0.001).

CONCLUSIONS: Mean treatment-episode and 6-month KA/cSCC treatment costs suggest a minor impact in the cost of advanced cancer treatments.