DecisionDx-Melanoma Test Independently Improved Identification of High-Risk Patients Compared to AJCC Staging in Stage I-II C...
April 23 2018 - 7:00AM
Business Wire
Posters presented at the Real World Dermatology
for Physician Assistants and Nurse Practitioners conference also
include data demonstrating test’s clinical utility
Castle Biosciences, Inc., a provider of molecular diagnostics to
improve cancer treatment decisions, today announced presentation of
results demonstrating that the use of the DecisionDx®-Melanoma gene
expression profile (GEP) test with American Joint Committee on
Cancer (AJCC) staging can improve accuracy of recurrence and
metastasis risk for patients with localized cutaneous melanoma.
The study titled, “Improved identification of high-risk, Stage
I-II cutaneous melanomas with the combination of American Joint
Committee on Cancer staging and a 31-gene expression profile test
result,” was presented as a poster at the 3rd Annual Real World
Dermatology for Physician Assistants and Nurse Practitioners
conference, held April 20-22, 2018 in Orlando, Florida.
“In this large Stage I-II melanoma study population, the
DecisionDx-Melanoma test improved risk prediction when used in
combination with AJCC risk assessment and showed independent
prognostic value,” commented study co-author Robert W. Cook, PhD,
Vice President, Medical Affairs and R&D at Castle Biosciences.
“Providing this information for risk assessment is important to
help guide patient management decisions for improved patient
outcomes.”
Study Background
For patients with cutaneous melanoma, accurate assessment of
recurrence risk is important to guide management plans including
imaging based surveillance, follow-up frequency and sentinel lymph
node biopsy recommendations that can lead to early detection of
metastatic disease. National guidelines suggest surveillance plans
based on AJCC stage, with Stage I-IIA considered low risk and Stage
IIB-IV considered high risk. The DecisionDx-Melanoma GEP test
accurately and independently predicts risk of recurrence and
metastasis, classifying patients as Class 1A (lowest risk) Class
1B/2A (lower or intermediate risk) or Class 2B (highest risk).
This study of 485 Stage I and II patients from a multicenter
cohort with long-term outcomes assessed the use of AJCC staging
combined with results from the DecisionDx-Melanoma GEP test to
improve recurrence risk prediction.
Key Study Findings:
- Patients who were classified as high
risk by both AJCC staging (Stage IIB-C) and the GEP test (Class 2B)
had significantly lower 5-year recurrence-free survival (RFS
33.4%), distant metastasis-free survival (DMFS 49.5%) and melanoma
specific survival (MSS 86.7%) compared to those identified as low
risk by both methods (RFS 96.1%, DMFS 97.3%, MSS 99.6%, p<0.0001
for all comparisons).
- Importantly, patients who were assessed
as low risk using AJCC staging (Stage I-IIA) but high risk using
the GEP test also demonstrated significantly worse outcomes (RFS
60.9%, DMFS 75.8%, MSS 85.9%) compared to patients who were
assessed as low risk using both methods (p<0.0001 for all
comparisons).
- Multivariate Cox regression analysis
indicated that both GEP high risk and AJCC high risk were
significant and independent predictors of RFS (GEP HR 6.8; AJCC HR
2.98, p<0.0001, both groups) and DMFS (GEP HR 8.5; AJCC HR 2.5,
p<0.001, both groups). For MSS, GEP Class 2B was the only
significant predictor (GEP HR 43.8, p<0.001; AJCC HR 1.04,
p<0.94).
Clinical Impact of DecisionDx-Melanoma
Test
A second poster titled, “Clinical impact of a 31-gene expression
profile test for cutaneous melanoma patients: a review of clinical
utility studies,” was also presented at the conference.
The poster highlights key findings across 5 published clinical
utility studies, including:
- In prospective and retrospective
multicenter clinical utility studies, the inclusion of the
DecisionDx-Melanoma test in risk assessment resulted in significant
differences in follow-up and surveillance when comparing low- and
high-risk patients.
- Findings across multiple clinical
impact studies show that incorporation of the GEP test consistently
impacts clinical management decisions for approximately 1 in 2
patients tested.
- Use of the DecisionDx-Melanoma GEP test
in combination with conventional staging methods can help develop a
more efficient and individualized follow-up plan based on clinical
factors and tumor biology.
About DecisionDx-Melanoma
The DecisionDx-Melanoma test uses tumor biology to predict
individual risk of melanoma recurrence and sentinel lymph node
positivity independent of traditional factors. Using tissue from
the primary melanoma, the test measures the expression of 31 genes.
The test has been validated in three multicenter studies that have
included 690 patients and have demonstrated consistent results.
Performance has also been confirmed in four prospective studies
including 702 patients. The consistent high performance and
accuracy demonstrated in these studies, which combined have
included over 1,300 patients, provides confidence in disease
management plans that incorporate DecisionDx-Melanoma test results.
Prediction of the likelihood of sentinel lymph node positivity has
also been validated in two prospective multicenter studies which
included over 1,400 patients. Clinical impact has been demonstrated
in multicenter and single-center studies showing that test results
impact clinical management decisions for one of every two patients
tested. More information about the test and disease can be found
at www.SkinMelanoma.com.
About Castle Biosciences
Castle Biosciences is a molecular diagnostics company dedicated
to helping patients and their physicians make the best possible
treatment and follow-up care decisions based on the individual
molecular signature of their tumor. The Company currently offers
tests for patients with cutaneous melanoma (DecisionDx®-Melanoma;
www.SkinMelanoma.com) and uveal melanoma (DecisionDx®-UM and
DecisionDx®-PRAME; www.MyUvealMelanoma.com), with development
programs in other underserved cancers. Castle Biosciences is based
in Friendswood, TX (Houston), and has laboratory operations in
Phoenix, AZ. More information can be found
at www.CastleBiosciences.com.
DecisionDx-Melanoma, DecisionDx-UM and DecisionDx-PRAME are the
trademarks of Castle Biosciences, Inc. Any other trademarks are the
property of their respective owners.
View source
version on businesswire.com: https://www.businesswire.com/news/home/20180423005414/en/
Castle Biosciences, Inc.Derek Maetzold,
866-788-9007President and CEOIR@castlebiosciences.com