Advanced cutaneous squamous cell carcinoma: A retrospective analysis of patient profiles and treatment patterns—Results of a non-interventional study of the DeCOG

Highlights

• Advanced cutaneous squamous cell carcinoma (aSCC) is a highly aggressive but poorly characterised disease.

• Real-life data of 190 patients describe patient characteristics and disease course.

• Only few patients with locally advanced SCC receive treatment.

• In metastatic SCC, EGFR inhibitors were mostly used with short treatment response.

• Despite older age and comorbidities, patients can be expected to be fit for treatment.

Abstract

Background

Advanced cutaneous squamous cell carcinoma (aSCC) is an area of unmet medical need and no treatment standards are established. Recently, an anti-PD-1 inhibitor received FDA breakthrough therapy designation. The aim of the study was to describe the clinical course, therapeutic management and prognosis of aSCC under real-life conditions.

Patients and methods

In a retrospective study performed in 24 German and Austrian hospitals and doctor's offices, patient and tumour characteristics of patients diagnosed with aSCC between January 1, 2010 and December 31, 2011 and their disease course was documented. Advanced SCC comprised either locally advanced SCCs (laSCC) or metastatic SCCs (mSCC) with any kind of metastatic spread.

Results

Data of 190 patients with aSCC were analysed. Median age at time of diagnosis of aSCC was 78 years. LaSCC was diagnosed in 76 patients (40%), 114 patients (60%) had mSCC. Once diagnosed with laSCC, most patients (59%) did not receive any therapy, whereas in 92% of mSCC patients at least one type of therapy was performed. Only 32 patients (29 mSCC, 3 laSCC) received systemic antitumour therapies, mostly EGFR inhibitor-based regimens. Mean duration of response was short (17-months laSCC patients, 3-months mSCC patients). Only 2 patients achieved a complete response, 27% had a partial response, 43% disease stabilisation. At diagnosis of aSCC, ECOG status was 0–1 in most patients. Non-malignant comorbidities influenced the decision on SCC-specific therapy in 39 patients (21%).

Conclusions

Our data show the high medical need for efficient and tolerable antitumour therapies and demonstrate that despite older age and comorbidities, most patients can be expected to be fit for treatment. This study provides a historical context for emerging aSCC treatments.

Introduction

Non-melanoma skin cancer (NMSC) is the most common cancer in white-skinned individuals [1], [2]. The number of NMSC in the U.S. population in 2006 was estimated at 3,507,693 [3]. In Germany, crude incidence rates for NMSC ranged from 163.1 to 227.5 per 100,000 persons per year in 2012 and are expected to double by 2030 [4]. Cutaneous squamous cell carcinoma is the second most common type of NMSC accounting for 20% of all NMSC. Precise incidence rates are difficult to ascertain as cutaneous SCC is not included in many cancer registries, but increasing incidence rates have been reported consistently [1], [4], [5], [6]. A population-based study in Minnesota compared the periods from years 1976–1984 with years 2000–2010 and revealed an increase of cutaneous SCC incidence from 62 to 163 cases per 100,000 person-years with a disproportionate increase of cutaneous SCC relative to basal cell carcinoma [7]. Although mortality from cutaneous SCC is only approximately 1–3%, total deaths from cutaneous SCC were estimated to be similar to the number of melanoma deaths, as melanoma is far more lethal but less common [8], [9], [10], [11]. Advanced cutaneous SCC (aSCC), has a dismal prognosis, 10-year survival rates are less than 20% for patients with regional lymph node involvement and less than 10% for patients with distant metastases [5]. Overall, aSCC is a poorly characterised disease with short treatment responses to systemic therapies. The promising results of anti-PD-1 antibody treatment of aSCC [12] could be the beginning of a new era in treatment options for patients. Disease characteristics and course of aSCC therefore need to be better characterised to be able to put the results of phase II trials of anti-PD-1 inhibitors into context. Here, we describe the clinical course, therapeutic management and prognosis of aSCC (locally advanced cutaneous SCC [laSCC], metastatic cutaneous SCC [mSCC]) under real-life conditions in a cohort unexposed to checkpoint inhibitors. The detailed information on epidemiology and clinical disease course of this cohort may serve as a historical reference as randomised clinical studies for aSCC are not expected due to the lack of comparator arms.