Castle is a company whose mission it is to serve individuals afflicted with orphan cancers and those who care for them. We define orphan cancers as those having an occurrence rate of less than 40,000 per year.

We are pursuing this mission by focusing on proprietary molecular diagnostic assays (or tests) that assist oncologists in individual risk-stratification. We have branded our tests as 'DecisionDx-...' because we believe that the results, as part a comprehensive baseline evaluation, will enable more personalized treatment plan decisions to be made by physicians. Our aim is to bring the promise of personalized medicine to those individuals afflicted with orphan cancers.

Two laboratory elements are important to the comprehensive baseline evaluation of an individual:

• Accurate diagnosis, and
• Risk stratification

While risk stratification tools have been / are being developed for common cancers, a gap exists in the orphan cancer area. By working with leading academic institutions, we hope to identify, develop, and offer laboratory tests to oncologists that will effectively close that gap.

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Castle has two molecular diagnostic assays that are available today...

Test for glioblastoma (DecisionDx-GBM)

Glioblastoma (also known as glioblastoma multiforme and GBM) is the most common and prevalent form of primary brain cancer. GBM is the brain tumor that afflicted Senator Kennedy. Today, GBM is diagnosed using traditional histo-pathology techniques. The diagnosis of GBM, however, does not discern prognosis of an individual patient. Because there appears to be two different response groups to today’s first line treatment, more specific information is needed. The most recent update of the DecisionDx-GBM clinical database found significant differentiation in progression-free survival and overall survival between the long-term responder group and the short-term (refractory) responder group (median overall survival: 377 weeks vs 56 weeks; p<0.0005). By determining a tumor’s specific molecular signature, DecisionDx-GBM can determine, prospectively, into which of these groups a patient falls.

Test for uveal melanoma (DecisionDx-UM)

Uveal melanoma (including choroidal melanoma, iris melanoma and ciliary body melanoma) is the most common form of eye cancer and the second most common site of melanoma. Treatments of enucleation, brachytherapy, and proton beam irradiation are all highly effective at controlling the primary eye tumor. However, by the time of primary tumor diagnosis, up to half of the patients with uveal melanoma already have microscopic or sub-clinical metastasis – predominantly to the liver. Unfortunately, these micrometastases are too small to be detected with today’s diagnostic techniques (imaging and liver function tests) until the metastatic tumor cells have multiplied many times and have become resistant to therapy. The DecisionDx-UM assay identifies a molecular signature that enables prospective stratification of the tumor’s metastatic risk. Tumors with a Class 1 signature are associated with a good prognosis and have low metastatic potential. Tumors with a Class 2 signature have a high metastatic potential and poorer prognosis.