Impact of a prognostic 40-gene expression profiling test on clinical management decisions for high-risk cutaneous squamous cell carcinoma

Figures & data

Figure 1. Clinician assessment of perceived risk of metastasis with molecular 40-GEP Class and clinicopathologic features in cutaneous squamous cell carcinoma. (A) Clinicians (n = 162) reported how risky they perceived a feature with 1 and 10 being the lowest and highest risk, respectively. Median values are plotted with error bars denoting 95% confidence intervals. p Values for comparisons of risk between two features are shown in the table and reflect Friedman tests with a Dunn’s correction for multiple comparisons. (B) Stacked histogram for clinician rating of risk of 40-GEP Class call: Class 1 (blue); Class 2A (orange); Class 2B (red).

Table 1. Clinician Demographics (n = 162).

Years in practice
Resident	11.7%
1–10 years	40.7%
11–20 years	14.2%
21–30 years	19.8%
>30 years	13.6%
Specialty
Dermatologist	77.2%
Dermatologist/Mohs surgeon	11.1%
Dermatopathologist	1.2%
Dermatology NP/PA	8.6%
Other	1.9%
Newly diagnosed invasive SCC patients seen in 2019
<50	31.5%
50–100	34.0%
100–200	16.7%
200–400	14.2%
>400	3.7%
High-risk SCC patients encountered
≤1%	12.3%
2–5%	34.0%
6–10%	30.2%
11–20%	14.8%
>20%	8.6%
SCC staging system used
I do not use any of these methods	30.9%
I am not aware of these methods	13.0%
I use a SCC staging system:	56.1%
AJCC7	17.6%
AJCC8	58.2%
BWH	24.2%

Abbreviations. NP/PA, nurse practitioner/physician assistant; AJCC7 or AJCC8, American Joint Committee on Cancer Staging Manual Edition 7 or 8; BWH, Brigham and Women’s Hospital.

Figure 2. Effect of 40-GEP test results on clinicians’ management decisions regarding: follow-up intervals, SLNB, nodal imaging, adjuvant radiation, and adjuvant chemotherapy. Percentage of clinicians who would develop either a low (blue bar), moderate (orange bar), or high (red bar) intensity management plan based on pre-test (no 40-GEP data), then, post-test (Class 1, 2A, or 2B) results. Using a Friedman’s test with Dunn’s multiple comparisons correction, statistical significance was determined for each vignette when all post-test 40-GEP results (Class 1, 2A, or 2B) were compared to pre-test 40-GEP (no 40-GEP). F/U: follow-up; SLNB: sentinel lymph node biopsy; imaging: nodal imaging; chemo: adjuvant chemotherapy; RT: adjuvant radiation.

Table 3. Comparison of changes by management modality.

Management modality*	Vignette 1						Vignette 2
	Class 1		Class 2A		Class 2B		Class 1		Class 2A		Class 2B
	Reduce	Increase	Reduce	Increase	Reduce	Increase	Reduce	Increase	Reduce	Increase	Reduce	Increase
Follow-up	47	4	18	22	4	86	43	4	20	15	1	72
Sentinel Lymph Node Biopsy	59	1	11	30	2	133	83	5	25	19	0	118
Nodal Imaging	35	4	12	20	2	103	44	4	26	13	1	89
Adjuvant Radiation	53	1	11	25	1	133	71	2	27	17	2	117
Adjuvant Chemotherapy	34	1	9	26	4	112	53	2	17	15	1	104

* Fisher’s exact test with Freeman-Halton extension indicated that each row had statistically significant differences p < .0001 when comparing Class 1, 2A, and 2B for a given modality.

Table 2. Clinical characteristics of patient vignettes.

Vignette	Age, sex	Tumor location	Size	Depth of lesion	Margin status	Histological differentiation	AJCC stage
1	67, male	Scalp	1.2 cm	1.2 mm	Well-defined	Poor	1
2	67, male	Scalp	1.2 cm	Beyond subcutaneous fat	Well-defined	Well	3