DecisionDx®-Melanoma Can Identify Melanoma Patients with Low Risk of Sentinel Lymph Node Positivity Who May Safely Forego Biopsy Surgery, New Independent Study Affirms

Rhea-AI Summary

Castle Biosciences (Nasdaq: CSTL) has published a new study in the World Journal of Surgical Oncology, demonstrating the effectiveness of their DecisionDx-Melanoma test in predicting sentinel lymph node (SLN) positivity risk. The study shows that the test can help reduce unnecessary sentinel lymph node biopsy (SLNB) surgeries by 33% in patients with T1-T2 melanoma tumors.

Key findings include:

• None of the patients classified as low-risk by DecisionDx-Melanoma had a positive SLN
• 31.9% SLN positivity rate in patients predicted to have >10% risk
• Potential SLNB reduction rate of 33% in patients with AJCC8 T1-T2 tumors

The study suggests that DecisionDx-Melanoma can improve patient selection for SLNB procedures, potentially reducing healthcare costs and unnecessary surgeries while maintaining good patient outcomes.

Positive

• DecisionDx-Melanoma test accurately predicted sentinel lymph node positivity risk
• Potential 33% reduction in unnecessary sentinel lymph node biopsy surgeries for T1-T2 melanoma patients
• 0% false negative rate for patients classified as low-risk by the test
• Improved patient selection for SLNB procedures, potentially reducing healthcare costs

Negative

• None.

Medical Research Analyst

This study provides compelling evidence for the clinical utility of the DecisionDx-Melanoma test in guiding sentinel lymph node biopsy (SLNB) decisions for melanoma patients. The test's ability to accurately predict SLN positivity risk could lead to a significant 33% reduction in unnecessary SLNB procedures for patients with T1-T2 tumors. This precision in patient stratification not only improves patient care by avoiding unnecessary surgeries but also has potential to reduce healthcare costs.

The test's performance is particularly impressive, with zero false negatives in the low-risk group and a high positivity rate in the high-risk group. This level of accuracy aligns well with current NCCN guidelines, potentially making it a valuable tool in clinical decision-making. However, it's important to note that while these results are promising, they come from a relatively small sample size of 156 patients. Larger, multi-center studies would be beneficial to further validate these findings across diverse patient populations.

Oncology Doctor

The DecisionDx-Melanoma test represents a significant advancement in personalized melanoma management. By integrating tumor biology with clinicopathologic factors, it offers a more nuanced approach to SLNB decision-making than traditional methods. The test's ability to accurately identify low-risk patients (5% predicted risk) who can safely forego SLNB is particularly valuable, as it spares these patients from unnecessary surgical procedures and their associated risks.

Moreover, the test's capacity to upstage high-risk patients ensures that those who need SLNB are more likely to receive it. This dual functionality could lead to more efficient resource allocation in melanoma care. However, it's important to remember that while this test is a powerful tool, it should be used in conjunction with clinical judgment and patient preferences. The ongoing DECIDE study will be vital in confirming the long-term outcomes of patients managed with this approach.

Financial Analyst

For Castle Biosciences (NASDAQ: CSTL), this study strengthens the value proposition of their DecisionDx-Melanoma test. The potential 33% reduction in unnecessary SLNB procedures for T1-T2 melanoma patients represents a significant market opportunity. With approximately $14,000 average cost per SLNB procedure, widespread adoption could lead to substantial healthcare savings, potentially driving demand for the test.

However, investors should note that market penetration and reimbursement will be critical for the test's commercial success. The strong clinical utility demonstrated in this study could support favorable coverage decisions from payers. Additionally, the ongoing DECIDE study, if positive, could further bolster the test's adoption. While this news is certainly positive for CSTL, the company's ability to translate these clinical results into revenue growth and profitability will be key metrics to watch in upcoming financial reports.

Using the DecisionDx-Melanoma test to guide sentinel lymph node biopsy (SLNB) surgery decisions could have significantly reduced the number of unnecessary SLNBs by 33% for patients with T1-T2 melanoma tumors

FRIENDSWOOD, Texas--(BUSINESS WIRE)-- Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced the publication of a new study further demonstrating that DecisionDx-Melanoma can precisely predict sentinel lymph node (SLN) positivity risk to help guide risk-aligned SLNB decisions, potentially reducing the number of unnecessary procedures and increasing the SLNB positivity yield if the procedure is performed. The paper, published in the World Journal of Surgical Oncology and titled “Integrating the melanoma 31-gene expression profile test with clinical and pathologic features can provide personalized precision estimates for sentinel lymph node positivity: an independent performance cohort,” is available here. 

“While SLNB is a common procedure used to determine possible tumor metastasis, our current criteria for biopsy may be overestimating a person’s risk of having a positive node, meaning we are probably performing more surgeries than necessary,” said lead author Joseph Bennett, M.D., MBA, surgical oncologist and system chief of surgery at LifeBridge Health in Baltimore, Maryland. “By using the DecisionDx-Melanoma test to accurately stratify patient risk and help guide these important decisions and discussions with patients, we can avoid doing SLNB procedures in low-risk patients without missing melanoma metastases.”

“Our DecisionDx-Melanoma test has significant clinical utility in helping to rule-out and rule-in SLNB procedures, as this study showed,” added Derek Maetzold, president and chief executive officer of Castle Biosciences. “And as demonstrated by data we shared earlier this year from our ongoing prospective, multicenter DECIDE study, patients with low-risk DecisionDx-Melanoma results whose providers use the test to help guide decisions to avoid SLNB surgery still experience good outcomes.”¹

The DecisionDx-Melanoma test integrates a patient’s tumor biology with their personal clinicopathologic factors to help answer the likelihood of SLN positivity and risk of recurrence in patients with melanoma. Current National Comprehensive Cancer Network (NCCN) guidelines suggest foregoing SLNB when the likelihood of finding a positive SLN is less than 5%, to consider SLNB when between 5-10% and to offer the surgery when the likelihood is above 10%. This study evaluated the performance of DecisionDx-Melanoma in predicting the risk of SLN positivity in 156 melanoma patients with known SLN outcomes at the ChristianaCare Helen F. Graham Cancer Center & Research Institute.

In the study, none of the patients (0/30) considered low-risk by the DecisionDx-Melanoma test (less than 5% predicted risk of SLN positivity) had a positive SLN, compared to a 31.9% SLN positivity rate (30/94, p<0.001) in patients predicted to have greater than 10% risk by the test. Of the 91 patients in the study who had American Joint Committee on Cancer eighth edition (AJCC8) T1-T2 tumors, the DecisionDx-Melanoma test identified 30 of them as low-risk, demonstrating a significant potential SLNB reduction rate of 33% in this patient population (30/91, p<0.001). Further, DecisionDx-Melanoma accurately downstaged or upstaged patients to a more definitive status to either forego or offer the SLNB procedure.

The results of this study demonstrate that DecisionDx-Melanoma can allow for more precise and personalized management of melanoma patients, improving patient selection for the SLNB surgical procedure and reducing unnecessary procedures and their associated healthcare costs. Moreover, the data provide evidence that DecisionDx-Melanoma can identify patients with a low risk of SLN positivity who may safely forego SLNB, as well as those with a higher risk who may want to consider the surgery.

About DecisionDx®-Melanoma

DecisionDx-Melanoma is a gene expression profile risk stratification test. It is designed to inform two clinical questions in the management of cutaneous melanoma: a patient’s individual risk of sentinel lymph node positivity and a patient's personal risk of melanoma recurrence and/or metastasis. By integrating tumor biology with clinical and pathologic factors using a validated proprietary algorithm, DecisionDx-Melanoma is designed to provide a comprehensive and clinically actionable result to guide risk-aligned patient care. DecisionDx-Melanoma has been shown to be associated with improved patient survival and has been studied in more than 10,000 patient samples. DecisionDx-Melanoma’s clinical value is supported by more than 50 peer-reviewed and published studies, providing confidence in disease management plans that incorporate the test’s results. Through June 30, 2024, DecisionDx-Melanoma has been ordered more than 173,000 times for patients diagnosed with cutaneous melanoma. Learn more at www.CastleBiosciences.com.

About Castle Biosciences

Castle Biosciences (Nasdaq: CSTL) is a leading diagnostics company improving health through innovative tests that guide patient care. The Company aims to transform disease management by keeping people first: patients, clinicians, employees and investors.

Castle’s current portfolio consists of tests for skin cancers, Barrett’s esophagus, mental health conditions and uveal melanoma. Additionally, the Company has active research and development programs for tests in other diseases with high clinical need, including its test in development to help guide systemic therapy selection for patients with moderate-to-severe atopic dermatitis, psoriasis and related conditions. To learn more, please visit www.CastleBiosciences.com and connect with us on LinkedIn, Facebook, X and Instagram.

DecisionDx-Melanoma, DecisionDx-CMSeq, DecisionDx-SCC, MyPath Melanoma, TissueCypher, IDgenetix, DecisionDx-UM, DecisionDx-PRAME and DecisionDx-UMSeq are trademarks of Castle Biosciences, Inc.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the “safe harbor” created by those sections. These forward-looking statements include, but are not limited to, statements concerning: the continued ability of the DecisionDx-Melanoma test to precisely predict SLN positivity risk, guide risk-aligned SLNB decisions and allow certain patients to safely forego SLNB. The words “can,” “may” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements that we make. These forward-looking statements involve risks and uncertainties that could cause our actual results to differ materially from those in the forward-looking statements, including, without limitation: subsequent study or trial results and findings may contradict earlier study or trial results and findings or may not support the results shown in this study, including with respect to the discussion of DecisionDx-Melanoma in this press release; actual application of our tests may not provide the aforementioned benefits to patients; and the risks set forth under the heading “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2023, our Quarterly Report on Form 10-Q for the quarter ended June 30, 2024, and in our other filings with the SEC. The forward-looking statements are applicable only as of the date on which they are made, and we do not assume any obligation to update any forward-looking statements, except as may be required by law.

1. Society of Surgical Oncology SSO 2024 Annual Meeting. Ann Surg Oncol 31 (Suppl 1), 1–294 (2024). https://doi.org/10.1245/s10434-024-15179-y: view presentation here

View source version on businesswire.com: https://www.businesswire.com/news/home/20240911059873/en/

Investor Contact:

Camilla Zuckero

czuckero@castlebiosciences.com

Media Contact:

Allison Marshall

amarshall@castlebiosciences.com

Source: Castle Biosciences Inc.

FAQ

What is the potential reduction rate of sentinel lymph node biopsies using DecisionDx-Melanoma for T1-T2 melanoma patients?

The study showed a potential 33% reduction rate in sentinel lymph node biopsies (SLNB) for patients with American Joint Committee on Cancer eighth edition (AJCC8) T1-T2 melanoma tumors when using the DecisionDx-Melanoma test.

How accurate was DecisionDx-Melanoma in identifying low-risk patients for sentinel lymph node positivity?

The DecisionDx-Melanoma test was highly accurate in identifying low-risk patients. In the study, none of the patients (0/30) considered low-risk by the test (less than 5% predicted risk of SLN positivity) had a positive sentinel lymph node.

What was the sentinel lymph node positivity rate for patients predicted to have high risk by DecisionDx-Melanoma?

For patients predicted to have greater than 10% risk of sentinel lymph node positivity by the DecisionDx-Melanoma test, the actual positivity rate was 31.9% (30/94 patients).

How can DecisionDx-Melanoma impact healthcare costs for melanoma patients?

DecisionDx-Melanoma can potentially reduce healthcare costs by improving patient selection for sentinel lymph node biopsy (SLNB) procedures, thereby reducing unnecessary surgeries while maintaining good patient outcomes.