Company: CSTL
Filing Date: 2025-11-03
Form Type: 10-Q
Source: 0001628280-25-048254
Chunk: 54

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-11-03
Form: 10-Q
Item: Item 1
Chunk 54
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 the nine months ended September 30, 2025 increased by $11.5 million, or 4.7%, to $257.2 million compared to the nine months ended September 30, 2024, due to a $36.9 million increase in revenue from our non-dermatologic tests and a $25.4 million decrease in revenue from our dermatologic tests.

The $36.9 million increase in revenue from our non-dermatologic tests was largely attributable to a 90.5% increase in tests report volumes for our TissueCypher test, and, to a much lesser extent, a higher realized ASP. Increases in our TissueCypher test report volumes reflect growth through our sales force efforts. Net revenue from our non-dermatologic tests as a percentage of total net revenue increased from 21.4% for the nine months ended September 30, 2024 to 34.8% for the nine months ended September 30, 2025.

The $25.4 million decrease from our dermatologic tests was primarily due to a lower ASP for DecisionDx-SCC test, where we stopped receiving Medicare coverage as of April 24, 2025, offset by 10.6% increase in DecisionDx-SCC test report volumes, and a 6.3% increase in DecisionDx-Melanoma test report volumes.

Cost of Sales (exclusive of amortization of acquired intangible assets)

Cost of sales (exclusive of amortization of acquired intangible assets) for the nine months ended September 30, 2025 increased by $8.7 million, or 19.7%, compared to the nine months ended September 30, 2024, primarily due to higher personnel costs, higher lab services cost, higher expenses for lab supplies, and higher depreciation expense. Increases in personnel costs reflect a higher headcount, due to additions made to support business growth in response to growing test report volumes, as well as merit and annual inflationary wage adjustment for existing employees. The increase in lab services expense was driven by higher test report volumes, while the rise in depreciation expense reflects continued investment in and expansion of our laboratory facilities.

Due to the nature of our business, a significant portion of our cost of sales expenses represents fixed costs associated with our testing operations. Accordingly, our cost of sales expense will not necessarily increase or decrease commensurately with the change in net revenues from period to period. We expect our cost of sales expenses (